redis.c split into many different C files.

networking related stuff moved into networking.c

moved more code

more work on layout of source code

SDS instantaneuos memory saving. By Pieter and Salvatore at VMware ;)

cleanly compiling again after the first split, now splitting it in more C files

moving more things around... work in progress

split replication code

splitting more

Sets split

Hash split

replication split

even more splitting

more splitting

minor change

redis.h

@@ -1,75 +0,0 @@
-/*
- * Copyright (c) 2009-2010, Salvatore Sanfilippo <antirez at gmail dot com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *   * Redistributions of source code must retain the above copyright notice,
- *     this list of conditions and the following disclaimer.
- *   * Redistributions in binary form must reproduce the above copyright
- *     notice, this list of conditions and the following disclaimer in the
- *     documentation and/or other materials provided with the distribution.
- *   * Neither the name of Redis nor the names of its contributors may be used
- *     to endorse or promote products derived from this software without
- *     specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef __REDIS_H__
-#define __REDIS_H__
-
-enum
-{
-  REG_GS = 0,
-# define REG_GS		REG_GS
-  REG_FS,
-# define REG_FS		REG_FS
-  REG_ES,
-# define REG_ES		REG_ES
-  REG_DS,
-# define REG_DS		REG_DS
-  REG_EDI,
-# define REG_EDI	REG_EDI
-  REG_ESI,
-# define REG_ESI	REG_ESI
-  REG_EBP,
-# define REG_EBP	REG_EBP
-  REG_ESP,
-# define REG_ESP	REG_ESP
-  REG_EBX,
-# define REG_EBX	REG_EBX
-  REG_EDX,
-# define REG_EDX	REG_EDX
-  REG_ECX,
-# define REG_ECX	REG_ECX
-  REG_EAX,
-# define REG_EAX	REG_EAX
-  REG_TRAPNO,
-# define REG_TRAPNO	REG_TRAPNO
-  REG_ERR,
-# define REG_ERR	REG_ERR
-  REG_EIP,
-# define REG_EIP	REG_EIP
-  REG_CS,
-# define REG_CS		REG_CS
-  REG_EFL,
-# define REG_EFL	REG_EFL
-  REG_UESP,
-# define REG_UESP	REG_UESP
-  REG_SS
-# define REG_SS	REG_SS
-};
-
-#endif

src/Makefile

@@ -15,7 +15,7 @@ endif
 CCOPT= $(CFLAGS) $(CCLINK) $(ARCH) $(PROF)
 DEBUG?= -g -rdynamic -ggdb 
 
-OBJ = adlist.o ae.o anet.o dict.o redis.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o
+OBJ = adlist.o ae.o anet.o dict.o redis.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o networking.o util.o object.o db.o replication.o rdb.o t_string.o t_list.o t_set.o t_zset.o t_hash.o config.o aof.o vm.o pubsub.o multi.o debug.o sort.o
 BENCHOBJ = ae.o anet.o redis-benchmark.o sds.o adlist.o zmalloc.o
 CLIOBJ = anet.o sds.o adlist.o redis-cli.o zmalloc.o linenoise.o
 CHECKDUMPOBJ = redis-check-dump.o lzf_c.o lzf_d.o
@@ -48,7 +48,7 @@ redis-check-dump.o: redis-check-dump.c lzf.h
 redis-cli.o: redis-cli.c fmacros.h anet.h sds.h adlist.h zmalloc.h \
   linenoise.h
 redis.o: redis.c fmacros.h config.h redis.h ae.h sds.h anet.h dict.h \
-  adlist.h zmalloc.h lzf.h pqsort.h zipmap.h ziplist.h sha1.h staticsymbols.h
+  adlist.h zmalloc.h lzf.h pqsort.h zipmap.h ziplist.h sha1.h
 release.o: release.c release.h
 sds.o: sds.c sds.h zmalloc.h
 sha1.o: sha1.c sha1.h
@@ -83,11 +83,8 @@ clean:
 dep:
 	$(CC) -MM *.c
 
-staticsymbols:
-	tclsh utils/build-static-symbols.tcl > staticsymbols.h
-
 test:
-	tclsh8.5 tests/test_helper.tcl --tags "${TAGS}"
+	(cd ..; tclsh8.5 tests/test_helper.tcl --tags "${TAGS}")
 
 bench:
 	./redis-benchmark

src/aof.c

@@ -0,0 +1,694 @@
+#include "redis.h"
+
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+/* Called when the user switches from "appendonly yes" to "appendonly no"
+ * at runtime using the CONFIG command. */
+void stopAppendOnly(void) {
+    flushAppendOnlyFile();
+    aof_fsync(server.appendfd);
+    close(server.appendfd);
+
+    server.appendfd = -1;
+    server.appendseldb = -1;
+    server.appendonly = 0;
+    /* rewrite operation in progress? kill it, wait child exit */
+    if (server.bgsavechildpid != -1) {
+        int statloc;
+
+        if (kill(server.bgsavechildpid,SIGKILL) != -1)
+            wait3(&statloc,0,NULL);
+        /* reset the buffer accumulating changes while the child saves */
+        sdsfree(server.bgrewritebuf);
+        server.bgrewritebuf = sdsempty();
+        server.bgsavechildpid = -1;
+    }
+}
+
+/* Called when the user switches from "appendonly no" to "appendonly yes"
+ * at runtime using the CONFIG command. */
+int startAppendOnly(void) {
+    server.appendonly = 1;
+    server.lastfsync = time(NULL);
+    server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644);
+    if (server.appendfd == -1) {
+        redisLog(REDIS_WARNING,"Used tried to switch on AOF via CONFIG, but I can't open the AOF file: %s",strerror(errno));
+        return REDIS_ERR;
+    }
+    if (rewriteAppendOnlyFileBackground() == REDIS_ERR) {
+        server.appendonly = 0;
+        close(server.appendfd);
+        redisLog(REDIS_WARNING,"Used tried to switch on AOF via CONFIG, I can't trigger a background AOF rewrite operation. Check the above logs for more info about the error.",strerror(errno));
+        return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
+/* Write the append only file buffer on disk.
+ *
+ * Since we are required to write the AOF before replying to the client,
+ * and the only way the client socket can get a write is entering when the
+ * the event loop, we accumulate all the AOF writes in a memory
+ * buffer and write it on disk using this function just before entering
+ * the event loop again. */
+void flushAppendOnlyFile(void) {
+    time_t now;
+    ssize_t nwritten;
+
+    if (sdslen(server.aofbuf) == 0) return;
+
+    /* We want to perform a single write. This should be guaranteed atomic
+     * at least if the filesystem we are writing is a real physical one.
+     * While this will save us against the server being killed I don't think
+     * there is much to do about the whole server stopping for power problems
+     * or alike */
+     nwritten = write(server.appendfd,server.aofbuf,sdslen(server.aofbuf));
+     if (nwritten != (signed)sdslen(server.aofbuf)) {
+        /* Ooops, we are in troubles. The best thing to do for now is
+         * aborting instead of giving the illusion that everything is
+         * working as expected. */
+         if (nwritten == -1) {
+            redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
+         } else {
+            redisLog(REDIS_WARNING,"Exiting on short write while writing to the append-only file: %s",strerror(errno));
+         }
+         exit(1);
+    }
+    sdsfree(server.aofbuf);
+    server.aofbuf = sdsempty();
+
+    /* Don't Fsync if no-appendfsync-on-rewrite is set to yes and we have
+     * childs performing heavy I/O on disk. */
+    if (server.no_appendfsync_on_rewrite &&
+        (server.bgrewritechildpid != -1 || server.bgsavechildpid != -1))
+            return;
+    /* Fsync if needed */
+    now = time(NULL);
+    if (server.appendfsync == APPENDFSYNC_ALWAYS ||
+        (server.appendfsync == APPENDFSYNC_EVERYSEC &&
+         now-server.lastfsync > 1))
+    {
+        /* aof_fsync is defined as fdatasync() for Linux in order to avoid
+         * flushing metadata. */
+        aof_fsync(server.appendfd); /* Let's try to get this data on the disk */
+        server.lastfsync = now;
+    }
+}
+
+sds catAppendOnlyGenericCommand(sds buf, int argc, robj **argv) {
+    int j;
+    buf = sdscatprintf(buf,"*%d\r\n",argc);
+    for (j = 0; j < argc; j++) {
+        robj *o = getDecodedObject(argv[j]);
+        buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
+        buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
+        buf = sdscatlen(buf,"\r\n",2);
+        decrRefCount(o);
+    }
+    return buf;
+}
+
+sds catAppendOnlyExpireAtCommand(sds buf, robj *key, robj *seconds) {
+    int argc = 3;
+    long when;
+    robj *argv[3];
+
+    /* Make sure we can use strtol */
+    seconds = getDecodedObject(seconds);
+    when = time(NULL)+strtol(seconds->ptr,NULL,10);
+    decrRefCount(seconds);
+
+    argv[0] = createStringObject("EXPIREAT",8);
+    argv[1] = key;
+    argv[2] = createObject(REDIS_STRING,
+        sdscatprintf(sdsempty(),"%ld",when));
+    buf = catAppendOnlyGenericCommand(buf, argc, argv);
+    decrRefCount(argv[0]);
+    decrRefCount(argv[2]);
+    return buf;
+}
+
+void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc) {
+    sds buf = sdsempty();
+    robj *tmpargv[3];
+
+    /* The DB this command was targetting is not the same as the last command
+     * we appendend. To issue a SELECT command is needed. */
+    if (dictid != server.appendseldb) {
+        char seldb[64];
+
+        snprintf(seldb,sizeof(seldb),"%d",dictid);
+        buf = sdscatprintf(buf,"*2\r\n$6\r\nSELECT\r\n$%lu\r\n%s\r\n",
+            (unsigned long)strlen(seldb),seldb);
+        server.appendseldb = dictid;
+    }
+
+    if (cmd->proc == expireCommand) {
+        /* Translate EXPIRE into EXPIREAT */
+        buf = catAppendOnlyExpireAtCommand(buf,argv[1],argv[2]);
+    } else if (cmd->proc == setexCommand) {
+        /* Translate SETEX to SET and EXPIREAT */
+        tmpargv[0] = createStringObject("SET",3);
+        tmpargv[1] = argv[1];
+        tmpargv[2] = argv[3];
+        buf = catAppendOnlyGenericCommand(buf,3,tmpargv);
+        decrRefCount(tmpargv[0]);
+        buf = catAppendOnlyExpireAtCommand(buf,argv[1],argv[2]);
+    } else {
+        buf = catAppendOnlyGenericCommand(buf,argc,argv);
+    }
+
+    /* Append to the AOF buffer. This will be flushed on disk just before
+     * of re-entering the event loop, so before the client will get a
+     * positive reply about the operation performed. */
+    server.aofbuf = sdscatlen(server.aofbuf,buf,sdslen(buf));
+
+    /* If a background append only file rewriting is in progress we want to
+     * accumulate the differences between the child DB and the current one
+     * in a buffer, so that when the child process will do its work we
+     * can append the differences to the new append only file. */
+    if (server.bgrewritechildpid != -1)
+        server.bgrewritebuf = sdscatlen(server.bgrewritebuf,buf,sdslen(buf));
+
+    sdsfree(buf);
+}
+
+/* In Redis commands are always executed in the context of a client, so in
+ * order to load the append only file we need to create a fake client. */
+struct redisClient *createFakeClient(void) {
+    struct redisClient *c = zmalloc(sizeof(*c));
+
+    selectDb(c,0);
+    c->fd = -1;
+    c->querybuf = sdsempty();
+    c->argc = 0;
+    c->argv = NULL;
+    c->flags = 0;
+    /* We set the fake client as a slave waiting for the synchronization
+     * so that Redis will not try to send replies to this client. */
+    c->replstate = REDIS_REPL_WAIT_BGSAVE_START;
+    c->reply = listCreate();
+    listSetFreeMethod(c->reply,decrRefCount);
+    listSetDupMethod(c->reply,dupClientReplyValue);
+    initClientMultiState(c);
+    return c;
+}
+
+void freeFakeClient(struct redisClient *c) {
+    sdsfree(c->querybuf);
+    listRelease(c->reply);
+    freeClientMultiState(c);
+    zfree(c);
+}
+
+/* Replay the append log file. On error REDIS_OK is returned. On non fatal
+ * error (the append only file is zero-length) REDIS_ERR is returned. On
+ * fatal error an error message is logged and the program exists. */
+int loadAppendOnlyFile(char *filename) {
+    struct redisClient *fakeClient;
+    FILE *fp = fopen(filename,"r");
+    struct redis_stat sb;
+    int appendonly = server.appendonly;
+
+    if (redis_fstat(fileno(fp),&sb) != -1 && sb.st_size == 0)
+        return REDIS_ERR;
+
+    if (fp == NULL) {
+        redisLog(REDIS_WARNING,"Fatal error: can't open the append log file for reading: %s",strerror(errno));
+        exit(1);
+    }
+
+    /* Temporarily disable AOF, to prevent EXEC from feeding a MULTI
+     * to the same file we're about to read. */
+    server.appendonly = 0;
+
+    fakeClient = createFakeClient();
+    while(1) {
+        int argc, j;
+        unsigned long len;
+        robj **argv;
+        char buf[128];
+        sds argsds;
+        struct redisCommand *cmd;
+        int force_swapout;
+
+        if (fgets(buf,sizeof(buf),fp) == NULL) {
+            if (feof(fp))
+                break;
+            else
+                goto readerr;
+        }
+        if (buf[0] != '*') goto fmterr;
+        argc = atoi(buf+1);
+        argv = zmalloc(sizeof(robj*)*argc);
+        for (j = 0; j < argc; j++) {
+            if (fgets(buf,sizeof(buf),fp) == NULL) goto readerr;
+            if (buf[0] != '$') goto fmterr;
+            len = strtol(buf+1,NULL,10);
+            argsds = sdsnewlen(NULL,len);
+            if (len && fread(argsds,len,1,fp) == 0) goto fmterr;
+            argv[j] = createObject(REDIS_STRING,argsds);
+            if (fread(buf,2,1,fp) == 0) goto fmterr; /* discard CRLF */
+        }
+
+        /* Command lookup */
+        cmd = lookupCommand(argv[0]->ptr);
+        if (!cmd) {
+            redisLog(REDIS_WARNING,"Unknown command '%s' reading the append only file", argv[0]->ptr);
+            exit(1);
+        }
+        /* Try object encoding */
+        if (cmd->flags & REDIS_CMD_BULK)
+            argv[argc-1] = tryObjectEncoding(argv[argc-1]);
+        /* Run the command in the context of a fake client */
+        fakeClient->argc = argc;
+        fakeClient->argv = argv;
+        cmd->proc(fakeClient);
+        /* Discard the reply objects list from the fake client */
+        while(listLength(fakeClient->reply))
+            listDelNode(fakeClient->reply,listFirst(fakeClient->reply));
+        /* Clean up, ready for the next command */
+        for (j = 0; j < argc; j++) decrRefCount(argv[j]);
+        zfree(argv);
+        /* Handle swapping while loading big datasets when VM is on */
+        force_swapout = 0;
+        if ((zmalloc_used_memory() - server.vm_max_memory) > 1024*1024*32)
+            force_swapout = 1;
+
+        if (server.vm_enabled && force_swapout) {
+            while (zmalloc_used_memory() > server.vm_max_memory) {
+                if (vmSwapOneObjectBlocking() == REDIS_ERR) break;
+            }
+        }
+    }
+
+    /* This point can only be reached when EOF is reached without errors.
+     * If the client is in the middle of a MULTI/EXEC, log error and quit. */
+    if (fakeClient->flags & REDIS_MULTI) goto readerr;
+
+    fclose(fp);
+    freeFakeClient(fakeClient);
+    server.appendonly = appendonly;
+    return REDIS_OK;
+
+readerr:
+    if (feof(fp)) {
+        redisLog(REDIS_WARNING,"Unexpected end of file reading the append only file");
+    } else {
+        redisLog(REDIS_WARNING,"Unrecoverable error reading the append only file: %s", strerror(errno));
+    }
+    exit(1);
+fmterr:
+    redisLog(REDIS_WARNING,"Bad file format reading the append only file");
+    exit(1);
+}
+
+/* Write binary-safe string into a file in the bulkformat
+ * $<count>\r\n<payload>\r\n */
+int fwriteBulkString(FILE *fp, char *s, unsigned long len) {
+    char cbuf[128];
+    int clen;
+    cbuf[0] = '$';
+    clen = 1+ll2string(cbuf+1,sizeof(cbuf)-1,len);
+    cbuf[clen++] = '\r';
+    cbuf[clen++] = '\n';
+    if (fwrite(cbuf,clen,1,fp) == 0) return 0;
+    if (len > 0 && fwrite(s,len,1,fp) == 0) return 0;
+    if (fwrite("\r\n",2,1,fp) == 0) return 0;
+    return 1;
+}
+
+/* Write a double value in bulk format $<count>\r\n<payload>\r\n */
+int fwriteBulkDouble(FILE *fp, double d) {
+    char buf[128], dbuf[128];
+
+    snprintf(dbuf,sizeof(dbuf),"%.17g\r\n",d);
+    snprintf(buf,sizeof(buf),"$%lu\r\n",(unsigned long)strlen(dbuf)-2);
+    if (fwrite(buf,strlen(buf),1,fp) == 0) return 0;
+    if (fwrite(dbuf,strlen(dbuf),1,fp) == 0) return 0;
+    return 1;
+}
+
+/* Write a long value in bulk format $<count>\r\n<payload>\r\n */
+int fwriteBulkLongLong(FILE *fp, long long l) {
+    char bbuf[128], lbuf[128];
+    unsigned int blen, llen;
+    llen = ll2string(lbuf,32,l);
+    blen = snprintf(bbuf,sizeof(bbuf),"$%u\r\n%s\r\n",llen,lbuf);
+    if (fwrite(bbuf,blen,1,fp) == 0) return 0;
+    return 1;
+}
+
+/* Delegate writing an object to writing a bulk string or bulk long long. */
+int fwriteBulkObject(FILE *fp, robj *obj) {
+    /* Avoid using getDecodedObject to help copy-on-write (we are often
+     * in a child process when this function is called). */
+    if (obj->encoding == REDIS_ENCODING_INT) {
+        return fwriteBulkLongLong(fp,(long)obj->ptr);
+    } else if (obj->encoding == REDIS_ENCODING_RAW) {
+        return fwriteBulkString(fp,obj->ptr,sdslen(obj->ptr));
+    } else {
+        redisPanic("Unknown string encoding");
+    }
+}
+
+/* Write a sequence of commands able to fully rebuild the dataset into
+ * "filename". Used both by REWRITEAOF and BGREWRITEAOF. */
+int rewriteAppendOnlyFile(char *filename) {
+    dictIterator *di = NULL;
+    dictEntry *de;
+    FILE *fp;
+    char tmpfile[256];
+    int j;
+    time_t now = time(NULL);
+
+    /* Note that we have to use a different temp name here compared to the
+     * one used by rewriteAppendOnlyFileBackground() function. */
+    snprintf(tmpfile,256,"temp-rewriteaof-%d.aof", (int) getpid());
+    fp = fopen(tmpfile,"w");
+    if (!fp) {
+        redisLog(REDIS_WARNING, "Failed rewriting the append only file: %s", strerror(errno));
+        return REDIS_ERR;
+    }
+    for (j = 0; j < server.dbnum; j++) {
+        char selectcmd[] = "*2\r\n$6\r\nSELECT\r\n";
+        redisDb *db = server.db+j;
+        dict *d = db->dict;
+        if (dictSize(d) == 0) continue;
+        di = dictGetIterator(d);
+        if (!di) {
+            fclose(fp);
+            return REDIS_ERR;
+        }
+
+        /* SELECT the new DB */
+        if (fwrite(selectcmd,sizeof(selectcmd)-1,1,fp) == 0) goto werr;
+        if (fwriteBulkLongLong(fp,j) == 0) goto werr;
+
+        /* Iterate this DB writing every entry */
+        while((de = dictNext(di)) != NULL) {
+            sds keystr = dictGetEntryKey(de);
+            robj key, *o;
+            time_t expiretime;
+            int swapped;
+
+            keystr = dictGetEntryKey(de);
+            o = dictGetEntryVal(de);
+            initStaticStringObject(key,keystr);
+            /* If the value for this key is swapped, load a preview in memory.
+             * We use a "swapped" flag to remember if we need to free the
+             * value object instead to just increment the ref count anyway
+             * in order to avoid copy-on-write of pages if we are forked() */
+            if (!server.vm_enabled || o->storage == REDIS_VM_MEMORY ||
+                o->storage == REDIS_VM_SWAPPING) {
+                swapped = 0;
+            } else {
+                o = vmPreviewObject(o);
+                swapped = 1;
+            }
+            expiretime = getExpire(db,&key);
+
+            /* Save the key and associated value */
+            if (o->type == REDIS_STRING) {
+                /* Emit a SET command */
+                char cmd[]="*3\r\n$3\r\nSET\r\n";
+                if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                /* Key and value */
+                if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                if (fwriteBulkObject(fp,o) == 0) goto werr;
+            } else if (o->type == REDIS_LIST) {
+                /* Emit the RPUSHes needed to rebuild the list */
+                char cmd[]="*3\r\n$5\r\nRPUSH\r\n";
+                if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+                    unsigned char *zl = o->ptr;
+                    unsigned char *p = ziplistIndex(zl,0);
+                    unsigned char *vstr;
+                    unsigned int vlen;
+                    long long vlong;
+
+                    while(ziplistGet(p,&vstr,&vlen,&vlong)) {
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                        if (vstr) {
+                            if (fwriteBulkString(fp,(char*)vstr,vlen) == 0)
+                                goto werr;
+                        } else {
+                            if (fwriteBulkLongLong(fp,vlong) == 0)
+                                goto werr;
+                        }
+                        p = ziplistNext(zl,p);
+                    }
+                } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+                    list *list = o->ptr;
+                    listNode *ln;
+                    listIter li;
+
+                    listRewind(list,&li);
+                    while((ln = listNext(&li))) {
+                        robj *eleobj = listNodeValue(ln);
+
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                        if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
+                    }
+                } else {
+                    redisPanic("Unknown list encoding");
+                }
+            } else if (o->type == REDIS_SET) {
+                /* Emit the SADDs needed to rebuild the set */
+                dict *set = o->ptr;
+                dictIterator *di = dictGetIterator(set);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    char cmd[]="*3\r\n$4\r\nSADD\r\n";
+                    robj *eleobj = dictGetEntryKey(de);
+
+                    if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                    if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                    if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
+                }
+                dictReleaseIterator(di);
+            } else if (o->type == REDIS_ZSET) {
+                /* Emit the ZADDs needed to rebuild the sorted set */
+                zset *zs = o->ptr;
+                dictIterator *di = dictGetIterator(zs->dict);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    char cmd[]="*4\r\n$4\r\nZADD\r\n";
+                    robj *eleobj = dictGetEntryKey(de);
+                    double *score = dictGetEntryVal(de);
+
+                    if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                    if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                    if (fwriteBulkDouble(fp,*score) == 0) goto werr;
+                    if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
+                }
+                dictReleaseIterator(di);
+            } else if (o->type == REDIS_HASH) {
+                char cmd[]="*4\r\n$4\r\nHSET\r\n";
+
+                /* Emit the HSETs needed to rebuild the hash */
+                if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+                    unsigned char *p = zipmapRewind(o->ptr);
+                    unsigned char *field, *val;
+                    unsigned int flen, vlen;
+
+                    while((p = zipmapNext(p,&field,&flen,&val,&vlen)) != NULL) {
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                        if (fwriteBulkString(fp,(char*)field,flen) == -1)
+                            return -1;
+                        if (fwriteBulkString(fp,(char*)val,vlen) == -1)
+                            return -1;
+                    }
+                } else {
+                    dictIterator *di = dictGetIterator(o->ptr);
+                    dictEntry *de;
+
+                    while((de = dictNext(di)) != NULL) {
+                        robj *field = dictGetEntryKey(de);
+                        robj *val = dictGetEntryVal(de);
+
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                        if (fwriteBulkObject(fp,field) == -1) return -1;
+                        if (fwriteBulkObject(fp,val) == -1) return -1;
+                    }
+                    dictReleaseIterator(di);
+                }
+            } else {
+                redisPanic("Unknown object type");
+            }
+            /* Save the expire time */
+            if (expiretime != -1) {
+                char cmd[]="*3\r\n$8\r\nEXPIREAT\r\n";
+                /* If this key is already expired skip it */
+                if (expiretime < now) continue;
+                if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                if (fwriteBulkObject(fp,&key) == 0) goto werr;
+                if (fwriteBulkLongLong(fp,expiretime) == 0) goto werr;
+            }
+            if (swapped) decrRefCount(o);
+        }
+        dictReleaseIterator(di);
+    }
+
+    /* Make sure data will not remain on the OS's output buffers */
+    fflush(fp);
+    aof_fsync(fileno(fp));
+    fclose(fp);
+
+    /* Use RENAME to make sure the DB file is changed atomically only
+     * if the generate DB file is ok. */
+    if (rename(tmpfile,filename) == -1) {
+        redisLog(REDIS_WARNING,"Error moving temp append only file on the final destination: %s", strerror(errno));
+        unlink(tmpfile);
+        return REDIS_ERR;
+    }
+    redisLog(REDIS_NOTICE,"SYNC append only file rewrite performed");
+    return REDIS_OK;
+
+werr:
+    fclose(fp);
+    unlink(tmpfile);
+    redisLog(REDIS_WARNING,"Write error writing append only file on disk: %s", strerror(errno));
+    if (di) dictReleaseIterator(di);
+    return REDIS_ERR;
+}
+
+/* This is how rewriting of the append only file in background works:
+ *
+ * 1) The user calls BGREWRITEAOF
+ * 2) Redis calls this function, that forks():
+ *    2a) the child rewrite the append only file in a temp file.
+ *    2b) the parent accumulates differences in server.bgrewritebuf.
+ * 3) When the child finished '2a' exists.
+ * 4) The parent will trap the exit code, if it's OK, will append the
+ *    data accumulated into server.bgrewritebuf into the temp file, and
+ *    finally will rename(2) the temp file in the actual file name.
+ *    The the new file is reopened as the new append only file. Profit!
+ */
+int rewriteAppendOnlyFileBackground(void) {
+    pid_t childpid;
+
+    if (server.bgrewritechildpid != -1) return REDIS_ERR;
+    if (server.vm_enabled) waitEmptyIOJobsQueue();
+    if ((childpid = fork()) == 0) {
+        /* Child */
+        char tmpfile[256];
+
+        if (server.vm_enabled) vmReopenSwapFile();
+        close(server.fd);
+        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) getpid());
+        if (rewriteAppendOnlyFile(tmpfile) == REDIS_OK) {
+            _exit(0);
+        } else {
+            _exit(1);
+        }
+    } else {
+        /* Parent */
+        if (childpid == -1) {
+            redisLog(REDIS_WARNING,
+                "Can't rewrite append only file in background: fork: %s",
+                strerror(errno));
+            return REDIS_ERR;
+        }
+        redisLog(REDIS_NOTICE,
+            "Background append only file rewriting started by pid %d",childpid);
+        server.bgrewritechildpid = childpid;
+        updateDictResizePolicy();
+        /* We set appendseldb to -1 in order to force the next call to the
+         * feedAppendOnlyFile() to issue a SELECT command, so the differences
+         * accumulated by the parent into server.bgrewritebuf will start
+         * with a SELECT statement and it will be safe to merge. */
+        server.appendseldb = -1;
+        return REDIS_OK;
+    }
+    return REDIS_OK; /* unreached */
+}
+
+void bgrewriteaofCommand(redisClient *c) {
+    if (server.bgrewritechildpid != -1) {
+        addReplySds(c,sdsnew("-ERR background append only file rewriting already in progress\r\n"));
+        return;
+    }
+    if (rewriteAppendOnlyFileBackground() == REDIS_OK) {
+        char *status = "+Background append only file rewriting started\r\n";
+        addReplySds(c,sdsnew(status));
+    } else {
+        addReply(c,shared.err);
+    }
+}
+
+void aofRemoveTempFile(pid_t childpid) {
+    char tmpfile[256];
+
+    snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) childpid);
+    unlink(tmpfile);
+}
+
+/* A background append only file rewriting (BGREWRITEAOF) terminated its work.
+ * Handle this. */
+void backgroundRewriteDoneHandler(int statloc) {
+    int exitcode = WEXITSTATUS(statloc);
+    int bysignal = WIFSIGNALED(statloc);
+
+    if (!bysignal && exitcode == 0) {
+        int fd;
+        char tmpfile[256];
+
+        redisLog(REDIS_NOTICE,
+            "Background append only file rewriting terminated with success");
+        /* Now it's time to flush the differences accumulated by the parent */
+        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) server.bgrewritechildpid);
+        fd = open(tmpfile,O_WRONLY|O_APPEND);
+        if (fd == -1) {
+            redisLog(REDIS_WARNING, "Not able to open the temp append only file produced by the child: %s", strerror(errno));
+            goto cleanup;
+        }
+        /* Flush our data... */
+        if (write(fd,server.bgrewritebuf,sdslen(server.bgrewritebuf)) !=
+                (signed) sdslen(server.bgrewritebuf)) {
+            redisLog(REDIS_WARNING, "Error or short write trying to flush the parent diff of the append log file in the child temp file: %s", strerror(errno));
+            close(fd);
+            goto cleanup;
+        }
+        redisLog(REDIS_NOTICE,"Parent diff flushed into the new append log file with success (%lu bytes)",sdslen(server.bgrewritebuf));
+        /* Now our work is to rename the temp file into the stable file. And
+         * switch the file descriptor used by the server for append only. */
+        if (rename(tmpfile,server.appendfilename) == -1) {
+            redisLog(REDIS_WARNING,"Can't rename the temp append only file into the stable one: %s", strerror(errno));
+            close(fd);
+            goto cleanup;
+        }
+        /* Mission completed... almost */
+        redisLog(REDIS_NOTICE,"Append only file successfully rewritten.");
+        if (server.appendfd != -1) {
+            /* If append only is actually enabled... */
+            close(server.appendfd);
+            server.appendfd = fd;
+            if (server.appendfsync != APPENDFSYNC_NO) aof_fsync(fd);
+            server.appendseldb = -1; /* Make sure it will issue SELECT */
+            redisLog(REDIS_NOTICE,"The new append only file was selected for future appends.");
+        } else {
+            /* If append only is disabled we just generate a dump in this
+             * format. Why not? */
+            close(fd);
+        }
+    } else if (!bysignal && exitcode != 0) {
+        redisLog(REDIS_WARNING, "Background append only file rewriting error");
+    } else {
+        redisLog(REDIS_WARNING,
+            "Background append only file rewriting terminated by signal %d",
+            WTERMSIG(statloc));
+    }
+cleanup:
+    sdsfree(server.bgrewritebuf);
+    server.bgrewritebuf = sdsempty();
+    aofRemoveTempFile(server.bgrewritechildpid);
+    server.bgrewritechildpid = -1;
+}

src/config.c

@@ -0,0 +1,438 @@
+#include "redis.h"
+
+/*-----------------------------------------------------------------------------
+ * Config file parsing
+ *----------------------------------------------------------------------------*/
+
+int yesnotoi(char *s) {
+    if (!strcasecmp(s,"yes")) return 1;
+    else if (!strcasecmp(s,"no")) return 0;
+    else return -1;
+}
+
+void appendServerSaveParams(time_t seconds, int changes) {
+    server.saveparams = zrealloc(server.saveparams,sizeof(struct saveparam)*(server.saveparamslen+1));
+    server.saveparams[server.saveparamslen].seconds = seconds;
+    server.saveparams[server.saveparamslen].changes = changes;
+    server.saveparamslen++;
+}
+
+void resetServerSaveParams() {
+    zfree(server.saveparams);
+    server.saveparams = NULL;
+    server.saveparamslen = 0;
+}
+
+/* I agree, this is a very rudimental way to load a configuration...
+   will improve later if the config gets more complex */
+void loadServerConfig(char *filename) {
+    FILE *fp;
+    char buf[REDIS_CONFIGLINE_MAX+1], *err = NULL;
+    int linenum = 0;
+    sds line = NULL;
+
+    if (filename[0] == '-' && filename[1] == '\0')
+        fp = stdin;
+    else {
+        if ((fp = fopen(filename,"r")) == NULL) {
+            redisLog(REDIS_WARNING, "Fatal error, can't open config file '%s'", filename);
+            exit(1);
+        }
+    }
+
+    while(fgets(buf,REDIS_CONFIGLINE_MAX+1,fp) != NULL) {
+        sds *argv;
+        int argc, j;
+
+        linenum++;
+        line = sdsnew(buf);
+        line = sdstrim(line," \t\r\n");
+
+        /* Skip comments and blank lines*/
+        if (line[0] == '#' || line[0] == '\0') {
+            sdsfree(line);
+            continue;
+        }
+
+        /* Split into arguments */
+        argv = sdssplitlen(line,sdslen(line)," ",1,&argc);
+        sdstolower(argv[0]);
+
+        /* Execute config directives */
+        if (!strcasecmp(argv[0],"timeout") && argc == 2) {
+            server.maxidletime = atoi(argv[1]);
+            if (server.maxidletime < 0) {
+                err = "Invalid timeout value"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"port") && argc == 2) {
+            server.port = atoi(argv[1]);
+            if (server.port < 1 || server.port > 65535) {
+                err = "Invalid port"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"bind") && argc == 2) {
+            server.bindaddr = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"save") && argc == 3) {
+            int seconds = atoi(argv[1]);
+            int changes = atoi(argv[2]);
+            if (seconds < 1 || changes < 0) {
+                err = "Invalid save parameters"; goto loaderr;
+            }
+            appendServerSaveParams(seconds,changes);
+        } else if (!strcasecmp(argv[0],"dir") && argc == 2) {
+            if (chdir(argv[1]) == -1) {
+                redisLog(REDIS_WARNING,"Can't chdir to '%s': %s",
+                    argv[1], strerror(errno));
+                exit(1);
+            }
+        } else if (!strcasecmp(argv[0],"loglevel") && argc == 2) {
+            if (!strcasecmp(argv[1],"debug")) server.verbosity = REDIS_DEBUG;
+            else if (!strcasecmp(argv[1],"verbose")) server.verbosity = REDIS_VERBOSE;
+            else if (!strcasecmp(argv[1],"notice")) server.verbosity = REDIS_NOTICE;
+            else if (!strcasecmp(argv[1],"warning")) server.verbosity = REDIS_WARNING;
+            else {
+                err = "Invalid log level. Must be one of debug, notice, warning";
+                goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"logfile") && argc == 2) {
+            FILE *logfp;
+
+            server.logfile = zstrdup(argv[1]);
+            if (!strcasecmp(server.logfile,"stdout")) {
+                zfree(server.logfile);
+                server.logfile = NULL;
+            }
+            if (server.logfile) {
+                /* Test if we are able to open the file. The server will not
+                 * be able to abort just for this problem later... */
+                logfp = fopen(server.logfile,"a");
+                if (logfp == NULL) {
+                    err = sdscatprintf(sdsempty(),
+                        "Can't open the log file: %s", strerror(errno));
+                    goto loaderr;
+                }
+                fclose(logfp);
+            }
+        } else if (!strcasecmp(argv[0],"databases") && argc == 2) {
+            server.dbnum = atoi(argv[1]);
+            if (server.dbnum < 1) {
+                err = "Invalid number of databases"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"include") && argc == 2) {
+            loadServerConfig(argv[1]);
+        } else if (!strcasecmp(argv[0],"maxclients") && argc == 2) {
+            server.maxclients = atoi(argv[1]);
+        } else if (!strcasecmp(argv[0],"maxmemory") && argc == 2) {
+            server.maxmemory = memtoll(argv[1],NULL);
+        } else if (!strcasecmp(argv[0],"slaveof") && argc == 3) {
+            server.masterhost = sdsnew(argv[1]);
+            server.masterport = atoi(argv[2]);
+            server.replstate = REDIS_REPL_CONNECT;
+        } else if (!strcasecmp(argv[0],"masterauth") && argc == 2) {
+        	server.masterauth = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"glueoutputbuf") && argc == 2) {
+            if ((server.glueoutputbuf = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"rdbcompression") && argc == 2) {
+            if ((server.rdbcompression = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"activerehashing") && argc == 2) {
+            if ((server.activerehashing = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"daemonize") && argc == 2) {
+            if ((server.daemonize = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"appendonly") && argc == 2) {
+            if ((server.appendonly = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"appendfilename") && argc == 2) {
+            zfree(server.appendfilename);
+            server.appendfilename = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"no-appendfsync-on-rewrite")
+                   && argc == 2) {
+            if ((server.no_appendfsync_on_rewrite= yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"appendfsync") && argc == 2) {
+            if (!strcasecmp(argv[1],"no")) {
+                server.appendfsync = APPENDFSYNC_NO;
+            } else if (!strcasecmp(argv[1],"always")) {
+                server.appendfsync = APPENDFSYNC_ALWAYS;
+            } else if (!strcasecmp(argv[1],"everysec")) {
+                server.appendfsync = APPENDFSYNC_EVERYSEC;
+            } else {
+                err = "argument must be 'no', 'always' or 'everysec'";
+                goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"requirepass") && argc == 2) {
+            server.requirepass = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"pidfile") && argc == 2) {
+            zfree(server.pidfile);
+            server.pidfile = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"dbfilename") && argc == 2) {
+            zfree(server.dbfilename);
+            server.dbfilename = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"vm-enabled") && argc == 2) {
+            if ((server.vm_enabled = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
+        } else if (!strcasecmp(argv[0],"vm-swap-file") && argc == 2) {
+            zfree(server.vm_swap_file);
+            server.vm_swap_file = zstrdup(argv[1]);
+        } else if (!strcasecmp(argv[0],"vm-max-memory") && argc == 2) {
+            server.vm_max_memory = memtoll(argv[1],NULL);
+        } else if (!strcasecmp(argv[0],"vm-page-size") && argc == 2) {
+            server.vm_page_size = memtoll(argv[1], NULL);
+        } else if (!strcasecmp(argv[0],"vm-pages") && argc == 2) {
+            server.vm_pages = memtoll(argv[1], NULL);
+        } else if (!strcasecmp(argv[0],"vm-max-threads") && argc == 2) {
+            server.vm_max_threads = strtoll(argv[1], NULL, 10);
+        } else if (!strcasecmp(argv[0],"hash-max-zipmap-entries") && argc == 2){
+            server.hash_max_zipmap_entries = memtoll(argv[1], NULL);
+        } else if (!strcasecmp(argv[0],"hash-max-zipmap-value") && argc == 2){
+            server.hash_max_zipmap_value = memtoll(argv[1], NULL);
+        } else if (!strcasecmp(argv[0],"list-max-ziplist-entries") && argc == 2){
+            server.list_max_ziplist_entries = memtoll(argv[1], NULL);
+        } else if (!strcasecmp(argv[0],"list-max-ziplist-value") && argc == 2){
+            server.list_max_ziplist_value = memtoll(argv[1], NULL);
+        } else {
+            err = "Bad directive or wrong number of arguments"; goto loaderr;
+        }
+        for (j = 0; j < argc; j++)
+            sdsfree(argv[j]);
+        zfree(argv);
+        sdsfree(line);
+    }
+    if (fp != stdin) fclose(fp);
+    return;
+
+loaderr:
+    fprintf(stderr, "\n*** FATAL CONFIG FILE ERROR ***\n");
+    fprintf(stderr, "Reading the configuration file, at line %d\n", linenum);
+    fprintf(stderr, ">>> '%s'\n", line);
+    fprintf(stderr, "%s\n", err);
+    exit(1);
+}
+
+/*-----------------------------------------------------------------------------
+ * CONFIG command for remote configuration
+ *----------------------------------------------------------------------------*/
+
+void configSetCommand(redisClient *c) {
+    robj *o = getDecodedObject(c->argv[3]);
+    long long ll;
+
+    if (!strcasecmp(c->argv[2]->ptr,"dbfilename")) {
+        zfree(server.dbfilename);
+        server.dbfilename = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"requirepass")) {
+        zfree(server.requirepass);
+        server.requirepass = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"masterauth")) {
+        zfree(server.masterauth);
+        server.masterauth = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"maxmemory")) {
+        if (getLongLongFromObject(o,&ll) == REDIS_ERR ||
+            ll < 0) goto badfmt;
+        server.maxmemory = ll;
+    } else if (!strcasecmp(c->argv[2]->ptr,"timeout")) {
+        if (getLongLongFromObject(o,&ll) == REDIS_ERR ||
+            ll < 0 || ll > LONG_MAX) goto badfmt;
+        server.maxidletime = ll;
+    } else if (!strcasecmp(c->argv[2]->ptr,"appendfsync")) {
+        if (!strcasecmp(o->ptr,"no")) {
+            server.appendfsync = APPENDFSYNC_NO;
+        } else if (!strcasecmp(o->ptr,"everysec")) {
+            server.appendfsync = APPENDFSYNC_EVERYSEC;
+        } else if (!strcasecmp(o->ptr,"always")) {
+            server.appendfsync = APPENDFSYNC_ALWAYS;
+        } else {
+            goto badfmt;
+        }
+    } else if (!strcasecmp(c->argv[2]->ptr,"no-appendfsync-on-rewrite")) {
+        int yn = yesnotoi(o->ptr);
+
+        if (yn == -1) goto badfmt;
+        server.no_appendfsync_on_rewrite = yn;
+    } else if (!strcasecmp(c->argv[2]->ptr,"appendonly")) {
+        int old = server.appendonly;
+        int new = yesnotoi(o->ptr);
+
+        if (new == -1) goto badfmt;
+        if (old != new) {
+            if (new == 0) {
+                stopAppendOnly();
+            } else {
+                if (startAppendOnly() == REDIS_ERR) {
+                    addReplySds(c,sdscatprintf(sdsempty(),
+                        "-ERR Unable to turn on AOF. Check server logs.\r\n"));
+                    decrRefCount(o);
+                    return;
+                }
+            }
+        }
+    } else if (!strcasecmp(c->argv[2]->ptr,"save")) {
+        int vlen, j;
+        sds *v = sdssplitlen(o->ptr,sdslen(o->ptr)," ",1,&vlen);
+
+        /* Perform sanity check before setting the new config:
+         * - Even number of args
+         * - Seconds >= 1, changes >= 0 */
+        if (vlen & 1) {
+            sdsfreesplitres(v,vlen);
+            goto badfmt;
+        }
+        for (j = 0; j < vlen; j++) {
+            char *eptr;
+            long val;
+
+            val = strtoll(v[j], &eptr, 10);
+            if (eptr[0] != '\0' ||
+                ((j & 1) == 0 && val < 1) ||
+                ((j & 1) == 1 && val < 0)) {
+                sdsfreesplitres(v,vlen);
+                goto badfmt;
+            }
+        }
+        /* Finally set the new config */
+        resetServerSaveParams();
+        for (j = 0; j < vlen; j += 2) {
+            time_t seconds;
+            int changes;
+
+            seconds = strtoll(v[j],NULL,10);
+            changes = strtoll(v[j+1],NULL,10);
+            appendServerSaveParams(seconds, changes);
+        }
+        sdsfreesplitres(v,vlen);
+    } else {
+        addReplySds(c,sdscatprintf(sdsempty(),
+            "-ERR not supported CONFIG parameter %s\r\n",
+            (char*)c->argv[2]->ptr));
+        decrRefCount(o);
+        return;
+    }
+    decrRefCount(o);
+    addReply(c,shared.ok);
+    return;
+
+badfmt: /* Bad format errors */
+    addReplySds(c,sdscatprintf(sdsempty(),
+        "-ERR invalid argument '%s' for CONFIG SET '%s'\r\n",
+            (char*)o->ptr,
+            (char*)c->argv[2]->ptr));
+    decrRefCount(o);
+}
+
+void configGetCommand(redisClient *c) {
+    robj *o = getDecodedObject(c->argv[2]);
+    robj *lenobj = createObject(REDIS_STRING,NULL);
+    char *pattern = o->ptr;
+    int matches = 0;
+
+    addReply(c,lenobj);
+    decrRefCount(lenobj);
+
+    if (stringmatch(pattern,"dbfilename",0)) {
+        addReplyBulkCString(c,"dbfilename");
+        addReplyBulkCString(c,server.dbfilename);
+        matches++;
+    }
+    if (stringmatch(pattern,"requirepass",0)) {
+        addReplyBulkCString(c,"requirepass");
+        addReplyBulkCString(c,server.requirepass);
+        matches++;
+    }
+    if (stringmatch(pattern,"masterauth",0)) {
+        addReplyBulkCString(c,"masterauth");
+        addReplyBulkCString(c,server.masterauth);
+        matches++;
+    }
+    if (stringmatch(pattern,"maxmemory",0)) {
+        char buf[128];
+
+        ll2string(buf,128,server.maxmemory);
+        addReplyBulkCString(c,"maxmemory");
+        addReplyBulkCString(c,buf);
+        matches++;
+    }
+    if (stringmatch(pattern,"timeout",0)) {
+        char buf[128];
+
+        ll2string(buf,128,server.maxidletime);
+        addReplyBulkCString(c,"timeout");
+        addReplyBulkCString(c,buf);
+        matches++;
+    }
+    if (stringmatch(pattern,"appendonly",0)) {
+        addReplyBulkCString(c,"appendonly");
+        addReplyBulkCString(c,server.appendonly ? "yes" : "no");
+        matches++;
+    }
+    if (stringmatch(pattern,"no-appendfsync-on-rewrite",0)) {
+        addReplyBulkCString(c,"no-appendfsync-on-rewrite");
+        addReplyBulkCString(c,server.no_appendfsync_on_rewrite ? "yes" : "no");
+        matches++;
+    }
+    if (stringmatch(pattern,"appendfsync",0)) {
+        char *policy;
+
+        switch(server.appendfsync) {
+        case APPENDFSYNC_NO: policy = "no"; break;
+        case APPENDFSYNC_EVERYSEC: policy = "everysec"; break;
+        case APPENDFSYNC_ALWAYS: policy = "always"; break;
+        default: policy = "unknown"; break; /* too harmless to panic */
+        }
+        addReplyBulkCString(c,"appendfsync");
+        addReplyBulkCString(c,policy);
+        matches++;
+    }
+    if (stringmatch(pattern,"save",0)) {
+        sds buf = sdsempty();
+        int j;
+
+        for (j = 0; j < server.saveparamslen; j++) {
+            buf = sdscatprintf(buf,"%ld %d",
+                    server.saveparams[j].seconds,
+                    server.saveparams[j].changes);
+            if (j != server.saveparamslen-1)
+                buf = sdscatlen(buf," ",1);
+        }
+        addReplyBulkCString(c,"save");
+        addReplyBulkCString(c,buf);
+        sdsfree(buf);
+        matches++;
+    }
+    decrRefCount(o);
+    lenobj->ptr = sdscatprintf(sdsempty(),"*%d\r\n",matches*2);
+}
+
+void configCommand(redisClient *c) {
+    if (!strcasecmp(c->argv[1]->ptr,"set")) {
+        if (c->argc != 4) goto badarity;
+        configSetCommand(c);
+    } else if (!strcasecmp(c->argv[1]->ptr,"get")) {
+        if (c->argc != 3) goto badarity;
+        configGetCommand(c);
+    } else if (!strcasecmp(c->argv[1]->ptr,"resetstat")) {
+        if (c->argc != 2) goto badarity;
+        server.stat_numcommands = 0;
+        server.stat_numconnections = 0;
+        server.stat_expiredkeys = 0;
+        server.stat_starttime = time(NULL);
+        addReply(c,shared.ok);
+    } else {
+        addReplySds(c,sdscatprintf(sdsempty(),
+            "-ERR CONFIG subcommand must be one of GET, SET, RESETSTAT\r\n"));
+    }
+    return;
+
+badarity:
+    addReplySds(c,sdscatprintf(sdsempty(),
+        "-ERR Wrong number of arguments for CONFIG %s\r\n",
+        (char*) c->argv[1]->ptr));
+}

src/db.c

@@ -0,0 +1,508 @@
+#include "redis.h"
+
+#include <signal.h>
+
+/*-----------------------------------------------------------------------------
+ * C-level DB API
+ *----------------------------------------------------------------------------*/
+
+robj *lookupKey(redisDb *db, robj *key) {
+    dictEntry *de = dictFind(db->dict,key->ptr);
+    if (de) {
+        robj *val = dictGetEntryVal(de);
+
+        if (server.vm_enabled) {
+            if (val->storage == REDIS_VM_MEMORY ||
+                val->storage == REDIS_VM_SWAPPING)
+            {
+                /* If we were swapping the object out, cancel the operation */
+                if (val->storage == REDIS_VM_SWAPPING)
+                    vmCancelThreadedIOJob(val);
+                /* Update the access time for the aging algorithm. */
+                val->lru = server.lruclock;
+            } else {
+                int notify = (val->storage == REDIS_VM_LOADING);
+
+                /* Our value was swapped on disk. Bring it at home. */
+                redisAssert(val->type == REDIS_VMPOINTER);
+                val = vmLoadObject(val);
+                dictGetEntryVal(de) = val;
+
+                /* Clients blocked by the VM subsystem may be waiting for
+                 * this key... */
+                if (notify) handleClientsBlockedOnSwappedKey(db,key);
+            }
+        }
+        return val;
+    } else {
+        return NULL;
+    }
+}
+
+robj *lookupKeyRead(redisDb *db, robj *key) {
+    expireIfNeeded(db,key);
+    return lookupKey(db,key);
+}
+
+robj *lookupKeyWrite(redisDb *db, robj *key) {
+    deleteIfVolatile(db,key);
+    touchWatchedKey(db,key);
+    return lookupKey(db,key);
+}
+
+robj *lookupKeyReadOrReply(redisClient *c, robj *key, robj *reply) {
+    robj *o = lookupKeyRead(c->db, key);
+    if (!o) addReply(c,reply);
+    return o;
+}
+
+robj *lookupKeyWriteOrReply(redisClient *c, robj *key, robj *reply) {
+    robj *o = lookupKeyWrite(c->db, key);
+    if (!o) addReply(c,reply);
+    return o;
+}
+
+/* Add the key to the DB. If the key already exists REDIS_ERR is returned,
+ * otherwise REDIS_OK is returned, and the caller should increment the
+ * refcount of 'val'. */
+int dbAdd(redisDb *db, robj *key, robj *val) {
+    /* Perform a lookup before adding the key, as we need to copy the
+     * key value. */
+    if (dictFind(db->dict, key->ptr) != NULL) {
+        return REDIS_ERR;
+    } else {
+        sds copy = sdsdup(key->ptr);
+        dictAdd(db->dict, copy, val);
+        return REDIS_OK;
+    }
+}
+
+/* If the key does not exist, this is just like dbAdd(). Otherwise
+ * the value associated to the key is replaced with the new one.
+ *
+ * On update (key already existed) 0 is returned. Otherwise 1. */
+int dbReplace(redisDb *db, robj *key, robj *val) {
+    if (dictFind(db->dict,key->ptr) == NULL) {
+        sds copy = sdsdup(key->ptr);
+        dictAdd(db->dict, copy, val);
+        return 1;
+    } else {
+        dictReplace(db->dict, key->ptr, val);
+        return 0;
+    }
+}
+
+int dbExists(redisDb *db, robj *key) {
+    return dictFind(db->dict,key->ptr) != NULL;
+}
+
+/* Return a random key, in form of a Redis object.
+ * If there are no keys, NULL is returned.
+ *
+ * The function makes sure to return keys not already expired. */
+robj *dbRandomKey(redisDb *db) {
+    struct dictEntry *de;
+
+    while(1) {
+        sds key;
+        robj *keyobj;
+
+        de = dictGetRandomKey(db->dict);
+        if (de == NULL) return NULL;
+
+        key = dictGetEntryKey(de);
+        keyobj = createStringObject(key,sdslen(key));
+        if (dictFind(db->expires,key)) {
+            if (expireIfNeeded(db,keyobj)) {
+                decrRefCount(keyobj);
+                continue; /* search for another key. This expired. */
+            }
+        }
+        return keyobj;
+    }
+}
+
+/* Delete a key, value, and associated expiration entry if any, from the DB */
+int dbDelete(redisDb *db, robj *key) {
+    /* Deleting an entry from the expires dict will not free the sds of
+     * the key, because it is shared with the main dictionary. */
+    if (dictSize(db->expires) > 0) dictDelete(db->expires,key->ptr);
+    return dictDelete(db->dict,key->ptr) == DICT_OK;
+}
+
+/* Empty the whole database */
+long long emptyDb() {
+    int j;
+    long long removed = 0;
+
+    for (j = 0; j < server.dbnum; j++) {
+        removed += dictSize(server.db[j].dict);
+        dictEmpty(server.db[j].dict);
+        dictEmpty(server.db[j].expires);
+    }
+    return removed;
+}
+
+int selectDb(redisClient *c, int id) {
+    if (id < 0 || id >= server.dbnum)
+        return REDIS_ERR;
+    c->db = &server.db[id];
+    return REDIS_OK;
+}
+
+/*-----------------------------------------------------------------------------
+ * Type agnostic commands operating on the key space
+ *----------------------------------------------------------------------------*/
+
+void flushdbCommand(redisClient *c) {
+    server.dirty += dictSize(c->db->dict);
+    touchWatchedKeysOnFlush(c->db->id);
+    dictEmpty(c->db->dict);
+    dictEmpty(c->db->expires);
+    addReply(c,shared.ok);
+}
+
+void flushallCommand(redisClient *c) {
+    touchWatchedKeysOnFlush(-1);
+    server.dirty += emptyDb();
+    addReply(c,shared.ok);
+    if (server.bgsavechildpid != -1) {
+        kill(server.bgsavechildpid,SIGKILL);
+        rdbRemoveTempFile(server.bgsavechildpid);
+    }
+    rdbSave(server.dbfilename);
+    server.dirty++;
+}
+
+void delCommand(redisClient *c) {
+    int deleted = 0, j;
+
+    for (j = 1; j < c->argc; j++) {
+        if (dbDelete(c->db,c->argv[j])) {
+            touchWatchedKey(c->db,c->argv[j]);
+            server.dirty++;
+            deleted++;
+        }
+    }
+    addReplyLongLong(c,deleted);
+}
+
+void existsCommand(redisClient *c) {
+    expireIfNeeded(c->db,c->argv[1]);
+    if (dbExists(c->db,c->argv[1])) {
+        addReply(c, shared.cone);
+    } else {
+        addReply(c, shared.czero);
+    }
+}
+
+void selectCommand(redisClient *c) {
+    int id = atoi(c->argv[1]->ptr);
+
+    if (selectDb(c,id) == REDIS_ERR) {
+        addReplySds(c,sdsnew("-ERR invalid DB index\r\n"));
+    } else {
+        addReply(c,shared.ok);
+    }
+}
+
+void randomkeyCommand(redisClient *c) {
+    robj *key;
+
+    if ((key = dbRandomKey(c->db)) == NULL) {
+        addReply(c,shared.nullbulk);
+        return;
+    }
+
+    addReplyBulk(c,key);
+    decrRefCount(key);
+}
+
+void keysCommand(redisClient *c) {
+    dictIterator *di;
+    dictEntry *de;
+    sds pattern = c->argv[1]->ptr;
+    int plen = sdslen(pattern);
+    unsigned long numkeys = 0;
+    robj *lenobj = createObject(REDIS_STRING,NULL);
+
+    di = dictGetIterator(c->db->dict);
+    addReply(c,lenobj);
+    decrRefCount(lenobj);
+    while((de = dictNext(di)) != NULL) {
+        sds key = dictGetEntryKey(de);
+        robj *keyobj;
+
+        if ((pattern[0] == '*' && pattern[1] == '\0') ||
+            stringmatchlen(pattern,plen,key,sdslen(key),0)) {
+            keyobj = createStringObject(key,sdslen(key));
+            if (expireIfNeeded(c->db,keyobj) == 0) {
+                addReplyBulk(c,keyobj);
+                numkeys++;
+            }
+            decrRefCount(keyobj);
+        }
+    }
+    dictReleaseIterator(di);
+    lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",numkeys);
+}
+
+void dbsizeCommand(redisClient *c) {
+    addReplySds(c,
+        sdscatprintf(sdsempty(),":%lu\r\n",dictSize(c->db->dict)));
+}
+
+void lastsaveCommand(redisClient *c) {
+    addReplySds(c,
+        sdscatprintf(sdsempty(),":%lu\r\n",server.lastsave));
+}
+
+void typeCommand(redisClient *c) {
+    robj *o;
+    char *type;
+
+    o = lookupKeyRead(c->db,c->argv[1]);
+    if (o == NULL) {
+        type = "+none";
+    } else {
+        switch(o->type) {
+        case REDIS_STRING: type = "+string"; break;
+        case REDIS_LIST: type = "+list"; break;
+        case REDIS_SET: type = "+set"; break;
+        case REDIS_ZSET: type = "+zset"; break;
+        case REDIS_HASH: type = "+hash"; break;
+        default: type = "+unknown"; break;
+        }
+    }
+    addReplySds(c,sdsnew(type));
+    addReply(c,shared.crlf);
+}
+
+void saveCommand(redisClient *c) {
+    if (server.bgsavechildpid != -1) {
+        addReplySds(c,sdsnew("-ERR background save in progress\r\n"));
+        return;
+    }
+    if (rdbSave(server.dbfilename) == REDIS_OK) {
+        addReply(c,shared.ok);
+    } else {
+        addReply(c,shared.err);
+    }
+}
+
+void bgsaveCommand(redisClient *c) {
+    if (server.bgsavechildpid != -1) {
+        addReplySds(c,sdsnew("-ERR background save already in progress\r\n"));
+        return;
+    }
+    if (rdbSaveBackground(server.dbfilename) == REDIS_OK) {
+        char *status = "+Background saving started\r\n";
+        addReplySds(c,sdsnew(status));
+    } else {
+        addReply(c,shared.err);
+    }
+}
+
+void shutdownCommand(redisClient *c) {
+    if (prepareForShutdown() == REDIS_OK)
+        exit(0);
+    addReplySds(c, sdsnew("-ERR Errors trying to SHUTDOWN. Check logs.\r\n"));
+}
+
+void renameGenericCommand(redisClient *c, int nx) {
+    robj *o;
+
+    /* To use the same key as src and dst is probably an error */
+    if (sdscmp(c->argv[1]->ptr,c->argv[2]->ptr) == 0) {
+        addReply(c,shared.sameobjecterr);
+        return;
+    }
+
+    if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr)) == NULL)
+        return;
+
+    incrRefCount(o);
+    deleteIfVolatile(c->db,c->argv[2]);
+    if (dbAdd(c->db,c->argv[2],o) == REDIS_ERR) {
+        if (nx) {
+            decrRefCount(o);
+            addReply(c,shared.czero);
+            return;
+        }
+        dbReplace(c->db,c->argv[2],o);
+    }
+    dbDelete(c->db,c->argv[1]);
+    touchWatchedKey(c->db,c->argv[2]);
+    server.dirty++;
+    addReply(c,nx ? shared.cone : shared.ok);
+}
+
+void renameCommand(redisClient *c) {
+    renameGenericCommand(c,0);
+}
+
+void renamenxCommand(redisClient *c) {
+    renameGenericCommand(c,1);
+}
+
+void moveCommand(redisClient *c) {
+    robj *o;
+    redisDb *src, *dst;
+    int srcid;
+
+    /* Obtain source and target DB pointers */
+    src = c->db;
+    srcid = c->db->id;
+    if (selectDb(c,atoi(c->argv[2]->ptr)) == REDIS_ERR) {
+        addReply(c,shared.outofrangeerr);
+        return;
+    }
+    dst = c->db;
+    selectDb(c,srcid); /* Back to the source DB */
+
+    /* If the user is moving using as target the same
+     * DB as the source DB it is probably an error. */
+    if (src == dst) {
+        addReply(c,shared.sameobjecterr);
+        return;
+    }
+
+    /* Check if the element exists and get a reference */
+    o = lookupKeyWrite(c->db,c->argv[1]);
+    if (!o) {
+        addReply(c,shared.czero);
+        return;
+    }
+
+    /* Try to add the element to the target DB */
+    deleteIfVolatile(dst,c->argv[1]);
+    if (dbAdd(dst,c->argv[1],o) == REDIS_ERR) {
+        addReply(c,shared.czero);
+        return;
+    }
+    incrRefCount(o);
+
+    /* OK! key moved, free the entry in the source DB */
+    dbDelete(src,c->argv[1]);
+    server.dirty++;
+    addReply(c,shared.cone);
+}
+
+/*-----------------------------------------------------------------------------
+ * Expires API
+ *----------------------------------------------------------------------------*/
+
+int removeExpire(redisDb *db, robj *key) {
+    /* An expire may only be removed if there is a corresponding entry in the
+     * main dict. Otherwise, the key will never be freed. */
+    redisAssert(dictFind(db->dict,key->ptr) != NULL);
+    if (dictDelete(db->expires,key->ptr) == DICT_OK) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+int setExpire(redisDb *db, robj *key, time_t when) {
+    dictEntry *de;
+
+    /* Reuse the sds from the main dict in the expire dict */
+    redisAssert((de = dictFind(db->dict,key->ptr)) != NULL);
+    if (dictAdd(db->expires,dictGetEntryKey(de),(void*)when) == DICT_ERR) {
+        return 0;
+    } else {
+        return 1;
+    }
+}
+
+/* Return the expire time of the specified key, or -1 if no expire
+ * is associated with this key (i.e. the key is non volatile) */
+time_t getExpire(redisDb *db, robj *key) {
+    dictEntry *de;
+
+    /* No expire? return ASAP */
+    if (dictSize(db->expires) == 0 ||
+       (de = dictFind(db->expires,key->ptr)) == NULL) return -1;
+
+    /* The entry was found in the expire dict, this means it should also
+     * be present in the main dict (safety check). */
+    redisAssert(dictFind(db->dict,key->ptr) != NULL);
+    return (time_t) dictGetEntryVal(de);
+}
+
+int expireIfNeeded(redisDb *db, robj *key) {
+    time_t when = getExpire(db,key);
+    if (when < 0) return 0;
+
+    /* Return when this key has not expired */
+    if (time(NULL) <= when) return 0;
+
+    /* Delete the key */
+    server.stat_expiredkeys++;
+    server.dirty++;
+    return dbDelete(db,key);
+}
+
+int deleteIfVolatile(redisDb *db, robj *key) {
+    if (getExpire(db,key) < 0) return 0;
+
+    /* Delete the key */
+    server.stat_expiredkeys++;
+    server.dirty++;
+    return dbDelete(db,key);
+}
+
+/*-----------------------------------------------------------------------------
+ * Expires Commands
+ *----------------------------------------------------------------------------*/
+
+void expireGenericCommand(redisClient *c, robj *key, robj *param, long offset) {
+    dictEntry *de;
+    time_t seconds;
+
+    if (getLongFromObjectOrReply(c, param, &seconds, NULL) != REDIS_OK) return;
+
+    seconds -= offset;
+
+    de = dictFind(c->db->dict,key->ptr);
+    if (de == NULL) {
+        addReply(c,shared.czero);
+        return;
+    }
+    if (seconds <= 0) {
+        if (dbDelete(c->db,key)) server.dirty++;
+        addReply(c, shared.cone);
+        return;
+    } else {
+        time_t when = time(NULL)+seconds;
+        if (setExpire(c->db,key,when)) {
+            addReply(c,shared.cone);
+            server.dirty++;
+        } else {
+            addReply(c,shared.czero);
+        }
+        return;
+    }
+}
+
+void expireCommand(redisClient *c) {
+    expireGenericCommand(c,c->argv[1],c->argv[2],0);
+}
+
+void expireatCommand(redisClient *c) {
+    expireGenericCommand(c,c->argv[1],c->argv[2],time(NULL));
+}
+
+void ttlCommand(redisClient *c) {
+    time_t expire;
+    int ttl = -1;
+
+    expire = getExpire(c->db,c->argv[1]);
+    if (expire != -1) {
+        ttl = (int) (expire-time(NULL));
+        if (ttl < 0) ttl = -1;
+    }
+    addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",ttl));
+}
+
+

src/debug.c

@@ -0,0 +1,309 @@
+#include "redis.h"
+#include "sha1.h"   /* SHA1 is used for DEBUG DIGEST */
+
+/* ================================= Debugging ============================== */
+
+/* Compute the sha1 of string at 's' with 'len' bytes long.
+ * The SHA1 is then xored againt the string pointed by digest.
+ * Since xor is commutative, this operation is used in order to
+ * "add" digests relative to unordered elements.
+ *
+ * So digest(a,b,c,d) will be the same of digest(b,a,c,d) */
+void xorDigest(unsigned char *digest, void *ptr, size_t len) {
+    SHA1_CTX ctx;
+    unsigned char hash[20], *s = ptr;
+    int j;
+
+    SHA1Init(&ctx);
+    SHA1Update(&ctx,s,len);
+    SHA1Final(hash,&ctx);
+
+    for (j = 0; j < 20; j++)
+        digest[j] ^= hash[j];
+}
+
+void xorObjectDigest(unsigned char *digest, robj *o) {
+    o = getDecodedObject(o);
+    xorDigest(digest,o->ptr,sdslen(o->ptr));
+    decrRefCount(o);
+}
+
+/* This function instead of just computing the SHA1 and xoring it
+ * against diget, also perform the digest of "digest" itself and
+ * replace the old value with the new one.
+ *
+ * So the final digest will be:
+ *
+ * digest = SHA1(digest xor SHA1(data))
+ *
+ * This function is used every time we want to preserve the order so
+ * that digest(a,b,c,d) will be different than digest(b,c,d,a)
+ *
+ * Also note that mixdigest("foo") followed by mixdigest("bar")
+ * will lead to a different digest compared to "fo", "obar".
+ */
+void mixDigest(unsigned char *digest, void *ptr, size_t len) {
+    SHA1_CTX ctx;
+    char *s = ptr;
+
+    xorDigest(digest,s,len);
+    SHA1Init(&ctx);
+    SHA1Update(&ctx,digest,20);
+    SHA1Final(digest,&ctx);
+}
+
+void mixObjectDigest(unsigned char *digest, robj *o) {
+    o = getDecodedObject(o);
+    mixDigest(digest,o->ptr,sdslen(o->ptr));
+    decrRefCount(o);
+}
+
+/* Compute the dataset digest. Since keys, sets elements, hashes elements
+ * are not ordered, we use a trick: every aggregate digest is the xor
+ * of the digests of their elements. This way the order will not change
+ * the result. For list instead we use a feedback entering the output digest
+ * as input in order to ensure that a different ordered list will result in
+ * a different digest. */
+void computeDatasetDigest(unsigned char *final) {
+    unsigned char digest[20];
+    char buf[128];
+    dictIterator *di = NULL;
+    dictEntry *de;
+    int j;
+    uint32_t aux;
+
+    memset(final,0,20); /* Start with a clean result */
+
+    for (j = 0; j < server.dbnum; j++) {
+        redisDb *db = server.db+j;
+
+        if (dictSize(db->dict) == 0) continue;
+        di = dictGetIterator(db->dict);
+
+        /* hash the DB id, so the same dataset moved in a different
+         * DB will lead to a different digest */
+        aux = htonl(j);
+        mixDigest(final,&aux,sizeof(aux));
+
+        /* Iterate this DB writing every entry */
+        while((de = dictNext(di)) != NULL) {
+            sds key;
+            robj *keyobj, *o;
+            time_t expiretime;
+
+            memset(digest,0,20); /* This key-val digest */
+            key = dictGetEntryKey(de);
+            keyobj = createStringObject(key,sdslen(key));
+
+            mixDigest(digest,key,sdslen(key));
+
+            /* Make sure the key is loaded if VM is active */
+            o = lookupKeyRead(db,keyobj);
+
+            aux = htonl(o->type);
+            mixDigest(digest,&aux,sizeof(aux));
+            expiretime = getExpire(db,keyobj);
+
+            /* Save the key and associated value */
+            if (o->type == REDIS_STRING) {
+                mixObjectDigest(digest,o);
+            } else if (o->type == REDIS_LIST) {
+                listTypeIterator *li = listTypeInitIterator(o,0,REDIS_TAIL);
+                listTypeEntry entry;
+                while(listTypeNext(li,&entry)) {
+                    robj *eleobj = listTypeGet(&entry);
+                    mixObjectDigest(digest,eleobj);
+                    decrRefCount(eleobj);
+                }
+                listTypeReleaseIterator(li);
+            } else if (o->type == REDIS_SET) {
+                dict *set = o->ptr;
+                dictIterator *di = dictGetIterator(set);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    robj *eleobj = dictGetEntryKey(de);
+
+                    xorObjectDigest(digest,eleobj);
+                }
+                dictReleaseIterator(di);
+            } else if (o->type == REDIS_ZSET) {
+                zset *zs = o->ptr;
+                dictIterator *di = dictGetIterator(zs->dict);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    robj *eleobj = dictGetEntryKey(de);
+                    double *score = dictGetEntryVal(de);
+                    unsigned char eledigest[20];
+
+                    snprintf(buf,sizeof(buf),"%.17g",*score);
+                    memset(eledigest,0,20);
+                    mixObjectDigest(eledigest,eleobj);
+                    mixDigest(eledigest,buf,strlen(buf));
+                    xorDigest(digest,eledigest,20);
+                }
+                dictReleaseIterator(di);
+            } else if (o->type == REDIS_HASH) {
+                hashTypeIterator *hi;
+                robj *obj;
+
+                hi = hashTypeInitIterator(o);
+                while (hashTypeNext(hi) != REDIS_ERR) {
+                    unsigned char eledigest[20];
+
+                    memset(eledigest,0,20);
+                    obj = hashTypeCurrent(hi,REDIS_HASH_KEY);
+                    mixObjectDigest(eledigest,obj);
+                    decrRefCount(obj);
+                    obj = hashTypeCurrent(hi,REDIS_HASH_VALUE);
+                    mixObjectDigest(eledigest,obj);
+                    decrRefCount(obj);
+                    xorDigest(digest,eledigest,20);
+                }
+                hashTypeReleaseIterator(hi);
+            } else {
+                redisPanic("Unknown object type");
+            }
+            /* If the key has an expire, add it to the mix */
+            if (expiretime != -1) xorDigest(digest,"!!expire!!",10);
+            /* We can finally xor the key-val digest to the final digest */
+            xorDigest(final,digest,20);
+            decrRefCount(keyobj);
+        }
+        dictReleaseIterator(di);
+    }
+}
+
+void debugCommand(redisClient *c) {
+    if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
+        *((char*)-1) = 'x';
+    } else if (!strcasecmp(c->argv[1]->ptr,"reload")) {
+        if (rdbSave(server.dbfilename) != REDIS_OK) {
+            addReply(c,shared.err);
+            return;
+        }
+        emptyDb();
+        if (rdbLoad(server.dbfilename) != REDIS_OK) {
+            addReply(c,shared.err);
+            return;
+        }
+        redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD");
+        addReply(c,shared.ok);
+    } else if (!strcasecmp(c->argv[1]->ptr,"loadaof")) {
+        emptyDb();
+        if (loadAppendOnlyFile(server.appendfilename) != REDIS_OK) {
+            addReply(c,shared.err);
+            return;
+        }
+        redisLog(REDIS_WARNING,"Append Only File loaded by DEBUG LOADAOF");
+        addReply(c,shared.ok);
+    } else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) {
+        dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
+        robj *val;
+
+        if (!de) {
+            addReply(c,shared.nokeyerr);
+            return;
+        }
+        val = dictGetEntryVal(de);
+        if (!server.vm_enabled || (val->storage == REDIS_VM_MEMORY ||
+                                   val->storage == REDIS_VM_SWAPPING)) {
+            char *strenc;
+
+            strenc = strEncoding(val->encoding);
+            addReplySds(c,sdscatprintf(sdsempty(),
+                "+Value at:%p refcount:%d "
+                "encoding:%s serializedlength:%lld\r\n",
+                (void*)val, val->refcount,
+                strenc, (long long) rdbSavedObjectLen(val,NULL)));
+        } else {
+            vmpointer *vp = (vmpointer*) val;
+            addReplySds(c,sdscatprintf(sdsempty(),
+                "+Value swapped at: page %llu "
+                "using %llu pages\r\n",
+                (unsigned long long) vp->page,
+                (unsigned long long) vp->usedpages));
+        }
+    } else if (!strcasecmp(c->argv[1]->ptr,"swapin") && c->argc == 3) {
+        lookupKeyRead(c->db,c->argv[2]);
+        addReply(c,shared.ok);
+    } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) {
+        dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
+        robj *val;
+        vmpointer *vp;
+
+        if (!server.vm_enabled) {
+            addReplySds(c,sdsnew("-ERR Virtual Memory is disabled\r\n"));
+            return;
+        }
+        if (!de) {
+            addReply(c,shared.nokeyerr);
+            return;
+        }
+        val = dictGetEntryVal(de);
+        /* Swap it */
+        if (val->storage != REDIS_VM_MEMORY) {
+            addReplySds(c,sdsnew("-ERR This key is not in memory\r\n"));
+        } else if (val->refcount != 1) {
+            addReplySds(c,sdsnew("-ERR Object is shared\r\n"));
+        } else if ((vp = vmSwapObjectBlocking(val)) != NULL) {
+            dictGetEntryVal(de) = vp;
+            addReply(c,shared.ok);
+        } else {
+            addReply(c,shared.err);
+        }
+    } else if (!strcasecmp(c->argv[1]->ptr,"populate") && c->argc == 3) {
+        long keys, j;
+        robj *key, *val;
+        char buf[128];
+
+        if (getLongFromObjectOrReply(c, c->argv[2], &keys, NULL) != REDIS_OK)
+            return;
+        for (j = 0; j < keys; j++) {
+            snprintf(buf,sizeof(buf),"key:%lu",j);
+            key = createStringObject(buf,strlen(buf));
+            if (lookupKeyRead(c->db,key) != NULL) {
+                decrRefCount(key);
+                continue;
+            }
+            snprintf(buf,sizeof(buf),"value:%lu",j);
+            val = createStringObject(buf,strlen(buf));
+            dbAdd(c->db,key,val);
+            decrRefCount(key);
+        }
+        addReply(c,shared.ok);
+    } else if (!strcasecmp(c->argv[1]->ptr,"digest") && c->argc == 2) {
+        unsigned char digest[20];
+        sds d = sdsnew("+");
+        int j;
+
+        computeDatasetDigest(digest);
+        for (j = 0; j < 20; j++)
+            d = sdscatprintf(d, "%02x",digest[j]);
+
+        d = sdscatlen(d,"\r\n",2);
+        addReplySds(c,d);
+    } else {
+        addReplySds(c,sdsnew(
+            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|SWAPIN <key>|SWAPOUT <key>|RELOAD]\r\n"));
+    }
+}
+
+void _redisAssert(char *estr, char *file, int line) {
+    redisLog(REDIS_WARNING,"=== ASSERTION FAILED ===");
+    redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true",file,line,estr);
+#ifdef HAVE_BACKTRACE
+    redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
+    *((char*)-1) = 'x';
+#endif
+}
+
+void _redisPanic(char *msg, char *file, int line) {
+    redisLog(REDIS_WARNING,"!!! Software Failure. Press left mouse button to continue");
+    redisLog(REDIS_WARNING,"Guru Meditation: %s #%s:%d",msg,file,line);
+#ifdef HAVE_BACKTRACE
+    redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
+    *((char*)-1) = 'x';
+#endif
+}

src/multi.c

@@ -0,0 +1,266 @@
+#include "redis.h"
+
+/* ================================ MULTI/EXEC ============================== */
+
+/* Client state initialization for MULTI/EXEC */
+void initClientMultiState(redisClient *c) {
+    c->mstate.commands = NULL;
+    c->mstate.count = 0;
+}
+
+/* Release all the resources associated with MULTI/EXEC state */
+void freeClientMultiState(redisClient *c) {
+    int j;
+
+    for (j = 0; j < c->mstate.count; j++) {
+        int i;
+        multiCmd *mc = c->mstate.commands+j;
+
+        for (i = 0; i < mc->argc; i++)
+            decrRefCount(mc->argv[i]);
+        zfree(mc->argv);
+    }
+    zfree(c->mstate.commands);
+}
+
+/* Add a new command into the MULTI commands queue */
+void queueMultiCommand(redisClient *c, struct redisCommand *cmd) {
+    multiCmd *mc;
+    int j;
+
+    c->mstate.commands = zrealloc(c->mstate.commands,
+            sizeof(multiCmd)*(c->mstate.count+1));
+    mc = c->mstate.commands+c->mstate.count;
+    mc->cmd = cmd;
+    mc->argc = c->argc;
+    mc->argv = zmalloc(sizeof(robj*)*c->argc);
+    memcpy(mc->argv,c->argv,sizeof(robj*)*c->argc);
+    for (j = 0; j < c->argc; j++)
+        incrRefCount(mc->argv[j]);
+    c->mstate.count++;
+}
+
+void multiCommand(redisClient *c) {
+    if (c->flags & REDIS_MULTI) {
+        addReplySds(c,sdsnew("-ERR MULTI calls can not be nested\r\n"));
+        return;
+    }
+    c->flags |= REDIS_MULTI;
+    addReply(c,shared.ok);
+}
+
+void discardCommand(redisClient *c) {
+    if (!(c->flags & REDIS_MULTI)) {
+        addReplySds(c,sdsnew("-ERR DISCARD without MULTI\r\n"));
+        return;
+    }
+
+    freeClientMultiState(c);
+    initClientMultiState(c);
+    c->flags &= (~REDIS_MULTI);
+    unwatchAllKeys(c);
+    addReply(c,shared.ok);
+}
+
+/* Send a MULTI command to all the slaves and AOF file. Check the execCommand
+ * implememntation for more information. */
+void execCommandReplicateMulti(redisClient *c) {
+    struct redisCommand *cmd;
+    robj *multistring = createStringObject("MULTI",5);
+
+    cmd = lookupCommand("multi");
+    if (server.appendonly)
+        feedAppendOnlyFile(cmd,c->db->id,&multistring,1);
+    if (listLength(server.slaves))
+        replicationFeedSlaves(server.slaves,c->db->id,&multistring,1);
+    decrRefCount(multistring);
+}
+
+void execCommand(redisClient *c) {
+    int j;
+    robj **orig_argv;
+    int orig_argc;
+
+    if (!(c->flags & REDIS_MULTI)) {
+        addReplySds(c,sdsnew("-ERR EXEC without MULTI\r\n"));
+        return;
+    }
+
+    /* Check if we need to abort the EXEC if some WATCHed key was touched.
+     * A failed EXEC will return a multi bulk nil object. */
+    if (c->flags & REDIS_DIRTY_CAS) {
+        freeClientMultiState(c);
+        initClientMultiState(c);
+        c->flags &= ~(REDIS_MULTI|REDIS_DIRTY_CAS);
+        unwatchAllKeys(c);
+        addReply(c,shared.nullmultibulk);
+        return;
+    }
+
+    /* Replicate a MULTI request now that we are sure the block is executed.
+     * This way we'll deliver the MULTI/..../EXEC block as a whole and
+     * both the AOF and the replication link will have the same consistency
+     * and atomicity guarantees. */
+    execCommandReplicateMulti(c);
+
+    /* Exec all the queued commands */
+    unwatchAllKeys(c); /* Unwatch ASAP otherwise we'll waste CPU cycles */
+    orig_argv = c->argv;
+    orig_argc = c->argc;
+    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",c->mstate.count));
+    for (j = 0; j < c->mstate.count; j++) {
+        c->argc = c->mstate.commands[j].argc;
+        c->argv = c->mstate.commands[j].argv;
+        call(c,c->mstate.commands[j].cmd);
+    }
+    c->argv = orig_argv;
+    c->argc = orig_argc;
+    freeClientMultiState(c);
+    initClientMultiState(c);
+    c->flags &= ~(REDIS_MULTI|REDIS_DIRTY_CAS);
+    /* Make sure the EXEC command is always replicated / AOF, since we
+     * always send the MULTI command (we can't know beforehand if the
+     * next operations will contain at least a modification to the DB). */
+    server.dirty++;
+}
+
+/* ===================== WATCH (CAS alike for MULTI/EXEC) ===================
+ *
+ * The implementation uses a per-DB hash table mapping keys to list of clients
+ * WATCHing those keys, so that given a key that is going to be modified
+ * we can mark all the associated clients as dirty.
+ *
+ * Also every client contains a list of WATCHed keys so that's possible to
+ * un-watch such keys when the client is freed or when UNWATCH is called. */
+
+/* In the client->watched_keys list we need to use watchedKey structures
+ * as in order to identify a key in Redis we need both the key name and the
+ * DB */
+typedef struct watchedKey {
+    robj *key;
+    redisDb *db;
+} watchedKey;
+
+/* Watch for the specified key */
+void watchForKey(redisClient *c, robj *key) {
+    list *clients = NULL;
+    listIter li;
+    listNode *ln;
+    watchedKey *wk;
+
+    /* Check if we are already watching for this key */
+    listRewind(c->watched_keys,&li);
+    while((ln = listNext(&li))) {
+        wk = listNodeValue(ln);
+        if (wk->db == c->db && equalStringObjects(key,wk->key))
+            return; /* Key already watched */
+    }
+    /* This key is not already watched in this DB. Let's add it */
+    clients = dictFetchValue(c->db->watched_keys,key);
+    if (!clients) { 
+        clients = listCreate();
+        dictAdd(c->db->watched_keys,key,clients);
+        incrRefCount(key);
+    }
+    listAddNodeTail(clients,c);
+    /* Add the new key to the lits of keys watched by this client */
+    wk = zmalloc(sizeof(*wk));
+    wk->key = key;
+    wk->db = c->db;
+    incrRefCount(key);
+    listAddNodeTail(c->watched_keys,wk);
+}
+
+/* Unwatch all the keys watched by this client. To clean the EXEC dirty
+ * flag is up to the caller. */
+void unwatchAllKeys(redisClient *c) {
+    listIter li;
+    listNode *ln;
+
+    if (listLength(c->watched_keys) == 0) return;
+    listRewind(c->watched_keys,&li);
+    while((ln = listNext(&li))) {
+        list *clients;
+        watchedKey *wk;
+
+        /* Lookup the watched key -> clients list and remove the client
+         * from the list */
+        wk = listNodeValue(ln);
+        clients = dictFetchValue(wk->db->watched_keys, wk->key);
+        redisAssert(clients != NULL);
+        listDelNode(clients,listSearchKey(clients,c));
+        /* Kill the entry at all if this was the only client */
+        if (listLength(clients) == 0)
+            dictDelete(wk->db->watched_keys, wk->key);
+        /* Remove this watched key from the client->watched list */
+        listDelNode(c->watched_keys,ln);
+        decrRefCount(wk->key);
+        zfree(wk);
+    }
+}
+
+/* "Touch" a key, so that if this key is being WATCHed by some client the
+ * next EXEC will fail. */
+void touchWatchedKey(redisDb *db, robj *key) {
+    list *clients;
+    listIter li;
+    listNode *ln;
+
+    if (dictSize(db->watched_keys) == 0) return;
+    clients = dictFetchValue(db->watched_keys, key);
+    if (!clients) return;
+
+    /* Mark all the clients watching this key as REDIS_DIRTY_CAS */
+    /* Check if we are already watching for this key */
+    listRewind(clients,&li);
+    while((ln = listNext(&li))) {
+        redisClient *c = listNodeValue(ln);
+
+        c->flags |= REDIS_DIRTY_CAS;
+    }
+}
+
+/* On FLUSHDB or FLUSHALL all the watched keys that are present before the
+ * flush but will be deleted as effect of the flushing operation should
+ * be touched. "dbid" is the DB that's getting the flush. -1 if it is
+ * a FLUSHALL operation (all the DBs flushed). */
+void touchWatchedKeysOnFlush(int dbid) {
+    listIter li1, li2;
+    listNode *ln;
+
+    /* For every client, check all the waited keys */
+    listRewind(server.clients,&li1);
+    while((ln = listNext(&li1))) {
+        redisClient *c = listNodeValue(ln);
+        listRewind(c->watched_keys,&li2);
+        while((ln = listNext(&li2))) {
+            watchedKey *wk = listNodeValue(ln);
+
+            /* For every watched key matching the specified DB, if the
+             * key exists, mark the client as dirty, as the key will be
+             * removed. */
+            if (dbid == -1 || wk->db->id == dbid) {
+                if (dictFind(wk->db->dict, wk->key->ptr) != NULL)
+                    c->flags |= REDIS_DIRTY_CAS;
+            }
+        }
+    }
+}
+
+void watchCommand(redisClient *c) {
+    int j;
+
+    if (c->flags & REDIS_MULTI) {
+        addReplySds(c,sdsnew("-ERR WATCH inside MULTI is not allowed\r\n"));
+        return;
+    }
+    for (j = 1; j < c->argc; j++)
+        watchForKey(c,c->argv[j]);
+    addReply(c,shared.ok);
+}
+
+void unwatchCommand(redisClient *c) {
+    unwatchAllKeys(c);
+    c->flags &= (~REDIS_DIRTY_CAS);
+    addReply(c,shared.ok);
+}

src/networking.c

@@ -0,0 +1,589 @@
+#include "redis.h"
+
+#include <sys/uio.h>
+
+void *dupClientReplyValue(void *o) {
+    incrRefCount((robj*)o);
+    return o;
+}
+
+int listMatchObjects(void *a, void *b) {
+    return equalStringObjects(a,b);
+}
+
+redisClient *createClient(int fd) {
+    redisClient *c = zmalloc(sizeof(*c));
+
+    anetNonBlock(NULL,fd);
+    anetTcpNoDelay(NULL,fd);
+    if (!c) return NULL;
+    selectDb(c,0);
+    c->fd = fd;
+    c->querybuf = sdsempty();
+    c->argc = 0;
+    c->argv = NULL;
+    c->bulklen = -1;
+    c->multibulk = 0;
+    c->mbargc = 0;
+    c->mbargv = NULL;
+    c->sentlen = 0;
+    c->flags = 0;
+    c->lastinteraction = time(NULL);
+    c->authenticated = 0;
+    c->replstate = REDIS_REPL_NONE;
+    c->reply = listCreate();
+    listSetFreeMethod(c->reply,decrRefCount);
+    listSetDupMethod(c->reply,dupClientReplyValue);
+    c->blocking_keys = NULL;
+    c->blocking_keys_num = 0;
+    c->io_keys = listCreate();
+    c->watched_keys = listCreate();
+    listSetFreeMethod(c->io_keys,decrRefCount);
+    c->pubsub_channels = dictCreate(&setDictType,NULL);
+    c->pubsub_patterns = listCreate();
+    listSetFreeMethod(c->pubsub_patterns,decrRefCount);
+    listSetMatchMethod(c->pubsub_patterns,listMatchObjects);
+    if (aeCreateFileEvent(server.el, c->fd, AE_READABLE,
+        readQueryFromClient, c) == AE_ERR) {
+        freeClient(c);
+        return NULL;
+    }
+    listAddNodeTail(server.clients,c);
+    initClientMultiState(c);
+    return c;
+}
+
+void addReply(redisClient *c, robj *obj) {
+    if (listLength(c->reply) == 0 &&
+        (c->replstate == REDIS_REPL_NONE ||
+         c->replstate == REDIS_REPL_ONLINE) &&
+        aeCreateFileEvent(server.el, c->fd, AE_WRITABLE,
+        sendReplyToClient, c) == AE_ERR) return;
+
+    if (server.vm_enabled && obj->storage != REDIS_VM_MEMORY) {
+        obj = dupStringObject(obj);
+        obj->refcount = 0; /* getDecodedObject() will increment the refcount */
+    }
+    listAddNodeTail(c->reply,getDecodedObject(obj));
+}
+
+void addReplySds(redisClient *c, sds s) {
+    robj *o = createObject(REDIS_STRING,s);
+    addReply(c,o);
+    decrRefCount(o);
+}
+
+void addReplyDouble(redisClient *c, double d) {
+    char buf[128];
+
+    snprintf(buf,sizeof(buf),"%.17g",d);
+    addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n%s\r\n",
+        (unsigned long) strlen(buf),buf));
+}
+
+void addReplyLongLong(redisClient *c, long long ll) {
+    char buf[128];
+    size_t len;
+
+    if (ll == 0) {
+        addReply(c,shared.czero);
+        return;
+    } else if (ll == 1) {
+        addReply(c,shared.cone);
+        return;
+    }
+    buf[0] = ':';
+    len = ll2string(buf+1,sizeof(buf)-1,ll);
+    buf[len+1] = '\r';
+    buf[len+2] = '\n';
+    addReplySds(c,sdsnewlen(buf,len+3));
+}
+
+void addReplyUlong(redisClient *c, unsigned long ul) {
+    char buf[128];
+    size_t len;
+
+    if (ul == 0) {
+        addReply(c,shared.czero);
+        return;
+    } else if (ul == 1) {
+        addReply(c,shared.cone);
+        return;
+    }
+    len = snprintf(buf,sizeof(buf),":%lu\r\n",ul);
+    addReplySds(c,sdsnewlen(buf,len));
+}
+
+void addReplyBulkLen(redisClient *c, robj *obj) {
+    size_t len, intlen;
+    char buf[128];
+
+    if (obj->encoding == REDIS_ENCODING_RAW) {
+        len = sdslen(obj->ptr);
+    } else {
+        long n = (long)obj->ptr;
+
+        /* Compute how many bytes will take this integer as a radix 10 string */
+        len = 1;
+        if (n < 0) {
+            len++;
+            n = -n;
+        }
+        while((n = n/10) != 0) {
+            len++;
+        }
+    }
+    buf[0] = '$';
+    intlen = ll2string(buf+1,sizeof(buf)-1,(long long)len);
+    buf[intlen+1] = '\r';
+    buf[intlen+2] = '\n';
+    addReplySds(c,sdsnewlen(buf,intlen+3));
+}
+
+void addReplyBulk(redisClient *c, robj *obj) {
+    addReplyBulkLen(c,obj);
+    addReply(c,obj);
+    addReply(c,shared.crlf);
+}
+
+/* In the CONFIG command we need to add vanilla C string as bulk replies */
+void addReplyBulkCString(redisClient *c, char *s) {
+    if (s == NULL) {
+        addReply(c,shared.nullbulk);
+    } else {
+        robj *o = createStringObject(s,strlen(s));
+        addReplyBulk(c,o);
+        decrRefCount(o);
+    }
+}
+
+void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) {
+    int cport, cfd;
+    char cip[128];
+    redisClient *c;
+    REDIS_NOTUSED(el);
+    REDIS_NOTUSED(mask);
+    REDIS_NOTUSED(privdata);
+
+    cfd = anetAccept(server.neterr, fd, cip, &cport);
+    if (cfd == AE_ERR) {
+        redisLog(REDIS_VERBOSE,"Accepting client connection: %s", server.neterr);
+        return;
+    }
+    redisLog(REDIS_VERBOSE,"Accepted %s:%d", cip, cport);
+    if ((c = createClient(cfd)) == NULL) {
+        redisLog(REDIS_WARNING,"Error allocating resoures for the client");
+        close(cfd); /* May be already closed, just ingore errors */
+        return;
+    }
+    /* If maxclient directive is set and this is one client more... close the
+     * connection. Note that we create the client instead to check before
+     * for this condition, since now the socket is already set in nonblocking
+     * mode and we can send an error for free using the Kernel I/O */
+    if (server.maxclients && listLength(server.clients) > server.maxclients) {
+        char *err = "-ERR max number of clients reached\r\n";
+
+        /* That's a best effort error message, don't check write errors */
+        if (write(c->fd,err,strlen(err)) == -1) {
+            /* Nothing to do, Just to avoid the warning... */
+        }
+        freeClient(c);
+        return;
+    }
+    server.stat_numconnections++;
+}
+
+static void freeClientArgv(redisClient *c) {
+    int j;
+
+    for (j = 0; j < c->argc; j++)
+        decrRefCount(c->argv[j]);
+    for (j = 0; j < c->mbargc; j++)
+        decrRefCount(c->mbargv[j]);
+    c->argc = 0;
+    c->mbargc = 0;
+}
+
+void freeClient(redisClient *c) {
+    listNode *ln;
+
+    /* Note that if the client we are freeing is blocked into a blocking
+     * call, we have to set querybuf to NULL *before* to call
+     * unblockClientWaitingData() to avoid processInputBuffer() will get
+     * called. Also it is important to remove the file events after
+     * this, because this call adds the READABLE event. */
+    sdsfree(c->querybuf);
+    c->querybuf = NULL;
+    if (c->flags & REDIS_BLOCKED)
+        unblockClientWaitingData(c);
+
+    /* UNWATCH all the keys */
+    unwatchAllKeys(c);
+    listRelease(c->watched_keys);
+    /* Unsubscribe from all the pubsub channels */
+    pubsubUnsubscribeAllChannels(c,0);
+    pubsubUnsubscribeAllPatterns(c,0);
+    dictRelease(c->pubsub_channels);
+    listRelease(c->pubsub_patterns);
+    /* Obvious cleanup */
+    aeDeleteFileEvent(server.el,c->fd,AE_READABLE);
+    aeDeleteFileEvent(server.el,c->fd,AE_WRITABLE);
+    listRelease(c->reply);
+    freeClientArgv(c);
+    close(c->fd);
+    /* Remove from the list of clients */
+    ln = listSearchKey(server.clients,c);
+    redisAssert(ln != NULL);
+    listDelNode(server.clients,ln);
+    /* Remove from the list of clients that are now ready to be restarted
+     * after waiting for swapped keys */
+    if (c->flags & REDIS_IO_WAIT && listLength(c->io_keys) == 0) {
+        ln = listSearchKey(server.io_ready_clients,c);
+        if (ln) {
+            listDelNode(server.io_ready_clients,ln);
+            server.vm_blocked_clients--;
+        }
+    }
+    /* Remove from the list of clients waiting for swapped keys */
+    while (server.vm_enabled && listLength(c->io_keys)) {
+        ln = listFirst(c->io_keys);
+        dontWaitForSwappedKey(c,ln->value);
+    }
+    listRelease(c->io_keys);
+    /* Master/slave cleanup */
+    if (c->flags & REDIS_SLAVE) {
+        if (c->replstate == REDIS_REPL_SEND_BULK && c->repldbfd != -1)
+            close(c->repldbfd);
+        list *l = (c->flags & REDIS_MONITOR) ? server.monitors : server.slaves;
+        ln = listSearchKey(l,c);
+        redisAssert(ln != NULL);
+        listDelNode(l,ln);
+    }
+    if (c->flags & REDIS_MASTER) {
+        server.master = NULL;
+        server.replstate = REDIS_REPL_CONNECT;
+    }
+    /* Release memory */
+    zfree(c->argv);
+    zfree(c->mbargv);
+    freeClientMultiState(c);
+    zfree(c);
+}
+
+#define GLUEREPLY_UP_TO (1024)
+static void glueReplyBuffersIfNeeded(redisClient *c) {
+    int copylen = 0;
+    char buf[GLUEREPLY_UP_TO];
+    listNode *ln;
+    listIter li;
+    robj *o;
+
+    listRewind(c->reply,&li);
+    while((ln = listNext(&li))) {
+        int objlen;
+
+        o = ln->value;
+        objlen = sdslen(o->ptr);
+        if (copylen + objlen <= GLUEREPLY_UP_TO) {
+            memcpy(buf+copylen,o->ptr,objlen);
+            copylen += objlen;
+            listDelNode(c->reply,ln);
+        } else {
+            if (copylen == 0) return;
+            break;
+        }
+    }
+    /* Now the output buffer is empty, add the new single element */
+    o = createObject(REDIS_STRING,sdsnewlen(buf,copylen));
+    listAddNodeHead(c->reply,o);
+}
+
+void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask) {
+    redisClient *c = privdata;
+    int nwritten = 0, totwritten = 0, objlen;
+    robj *o;
+    REDIS_NOTUSED(el);
+    REDIS_NOTUSED(mask);
+
+    /* Use writev() if we have enough buffers to send */
+    if (!server.glueoutputbuf &&
+        listLength(c->reply) > REDIS_WRITEV_THRESHOLD &&
+        !(c->flags & REDIS_MASTER))
+    {
+        sendReplyToClientWritev(el, fd, privdata, mask);
+        return;
+    }
+
+    while(listLength(c->reply)) {
+        if (server.glueoutputbuf && listLength(c->reply) > 1)
+            glueReplyBuffersIfNeeded(c);
+
+        o = listNodeValue(listFirst(c->reply));
+        objlen = sdslen(o->ptr);
+
+        if (objlen == 0) {
+            listDelNode(c->reply,listFirst(c->reply));
+            continue;
+        }
+
+        if (c->flags & REDIS_MASTER) {
+            /* Don't reply to a master */
+            nwritten = objlen - c->sentlen;
+        } else {
+            nwritten = write(fd, ((char*)o->ptr)+c->sentlen, objlen - c->sentlen);
+            if (nwritten <= 0) break;
+        }
+        c->sentlen += nwritten;
+        totwritten += nwritten;
+        /* If we fully sent the object on head go to the next one */
+        if (c->sentlen == objlen) {
+            listDelNode(c->reply,listFirst(c->reply));
+            c->sentlen = 0;
+        }
+        /* Note that we avoid to send more thank REDIS_MAX_WRITE_PER_EVENT
+         * bytes, in a single threaded server it's a good idea to serve
+         * other clients as well, even if a very large request comes from
+         * super fast link that is always able to accept data (in real world
+         * scenario think about 'KEYS *' against the loopback interfae) */
+        if (totwritten > REDIS_MAX_WRITE_PER_EVENT) break;
+    }
+    if (nwritten == -1) {
+        if (errno == EAGAIN) {
+            nwritten = 0;
+        } else {
+            redisLog(REDIS_VERBOSE,
+                "Error writing to client: %s", strerror(errno));
+            freeClient(c);
+            return;
+        }
+    }
+    if (totwritten > 0) c->lastinteraction = time(NULL);
+    if (listLength(c->reply) == 0) {
+        c->sentlen = 0;
+        aeDeleteFileEvent(server.el,c->fd,AE_WRITABLE);
+    }
+}
+
+void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int mask)
+{
+    redisClient *c = privdata;
+    int nwritten = 0, totwritten = 0, objlen, willwrite;
+    robj *o;
+    struct iovec iov[REDIS_WRITEV_IOVEC_COUNT];
+    int offset, ion = 0;
+    REDIS_NOTUSED(el);
+    REDIS_NOTUSED(mask);
+
+    listNode *node;
+    while (listLength(c->reply)) {
+        offset = c->sentlen;
+        ion = 0;
+        willwrite = 0;
+
+        /* fill-in the iov[] array */
+        for(node = listFirst(c->reply); node; node = listNextNode(node)) {
+            o = listNodeValue(node);
+            objlen = sdslen(o->ptr);
+
+            if (totwritten + objlen - offset > REDIS_MAX_WRITE_PER_EVENT)
+                break;
+
+            if(ion == REDIS_WRITEV_IOVEC_COUNT)
+                break; /* no more iovecs */
+
+            iov[ion].iov_base = ((char*)o->ptr) + offset;
+            iov[ion].iov_len = objlen - offset;
+            willwrite += objlen - offset;
+            offset = 0; /* just for the first item */
+            ion++;
+        }
+
+        if(willwrite == 0)
+            break;
+
+        /* write all collected blocks at once */
+        if((nwritten = writev(fd, iov, ion)) < 0) {
+            if (errno != EAGAIN) {
+                redisLog(REDIS_VERBOSE,
+                         "Error writing to client: %s", strerror(errno));
+                freeClient(c);
+                return;
+            }
+            break;
+        }
+
+        totwritten += nwritten;
+        offset = c->sentlen;
+
+        /* remove written robjs from c->reply */
+        while (nwritten && listLength(c->reply)) {
+            o = listNodeValue(listFirst(c->reply));
+            objlen = sdslen(o->ptr);
+
+            if(nwritten >= objlen - offset) {
+                listDelNode(c->reply, listFirst(c->reply));
+                nwritten -= objlen - offset;
+                c->sentlen = 0;
+            } else {
+                /* partial write */
+                c->sentlen += nwritten;
+                break;
+            }
+            offset = 0;
+        }
+    }
+
+    if (totwritten > 0)
+        c->lastinteraction = time(NULL);
+
+    if (listLength(c->reply) == 0) {
+        c->sentlen = 0;
+        aeDeleteFileEvent(server.el,c->fd,AE_WRITABLE);
+    }
+}
+
+/* resetClient prepare the client to process the next command */
+void resetClient(redisClient *c) {
+    freeClientArgv(c);
+    c->bulklen = -1;
+    c->multibulk = 0;
+}
+
+void closeTimedoutClients(void) {
+    redisClient *c;
+    listNode *ln;
+    time_t now = time(NULL);
+    listIter li;
+
+    listRewind(server.clients,&li);
+    while ((ln = listNext(&li)) != NULL) {
+        c = listNodeValue(ln);
+        if (server.maxidletime &&
+            !(c->flags & REDIS_SLAVE) &&    /* no timeout for slaves */
+            !(c->flags & REDIS_MASTER) &&   /* no timeout for masters */
+            dictSize(c->pubsub_channels) == 0 && /* no timeout for pubsub */
+            listLength(c->pubsub_patterns) == 0 &&
+            (now - c->lastinteraction > server.maxidletime))
+        {
+            redisLog(REDIS_VERBOSE,"Closing idle client");
+            freeClient(c);
+        } else if (c->flags & REDIS_BLOCKED) {
+            if (c->blockingto != 0 && c->blockingto < now) {
+                addReply(c,shared.nullmultibulk);
+                unblockClientWaitingData(c);
+            }
+        }
+    }
+}
+
+void processInputBuffer(redisClient *c) {
+again:
+    /* Before to process the input buffer, make sure the client is not
+     * waitig for a blocking operation such as BLPOP. Note that the first
+     * iteration the client is never blocked, otherwise the processInputBuffer
+     * would not be called at all, but after the execution of the first commands
+     * in the input buffer the client may be blocked, and the "goto again"
+     * will try to reiterate. The following line will make it return asap. */
+    if (c->flags & REDIS_BLOCKED || c->flags & REDIS_IO_WAIT) return;
+    if (c->bulklen == -1) {
+        /* Read the first line of the query */
+        char *p = strchr(c->querybuf,'\n');
+        size_t querylen;
+
+        if (p) {
+            sds query, *argv;
+            int argc, j;
+
+            query = c->querybuf;
+            c->querybuf = sdsempty();
+            querylen = 1+(p-(query));
+            if (sdslen(query) > querylen) {
+                /* leave data after the first line of the query in the buffer */
+                c->querybuf = sdscatlen(c->querybuf,query+querylen,sdslen(query)-querylen);
+            }
+            *p = '\0'; /* remove "\n" */
+            if (*(p-1) == '\r') *(p-1) = '\0'; /* and "\r" if any */
+            sdsupdatelen(query);
+
+            /* Now we can split the query in arguments */
+            argv = sdssplitlen(query,sdslen(query)," ",1,&argc);
+            sdsfree(query);
+
+            if (c->argv) zfree(c->argv);
+            c->argv = zmalloc(sizeof(robj*)*argc);
+
+            for (j = 0; j < argc; j++) {
+                if (sdslen(argv[j])) {
+                    c->argv[c->argc] = createObject(REDIS_STRING,argv[j]);
+                    c->argc++;
+                } else {
+                    sdsfree(argv[j]);
+                }
+            }
+            zfree(argv);
+            if (c->argc) {
+                /* Execute the command. If the client is still valid
+                 * after processCommand() return and there is something
+                 * on the query buffer try to process the next command. */
+                if (processCommand(c) && sdslen(c->querybuf)) goto again;
+            } else {
+                /* Nothing to process, argc == 0. Just process the query
+                 * buffer if it's not empty or return to the caller */
+                if (sdslen(c->querybuf)) goto again;
+            }
+            return;
+        } else if (sdslen(c->querybuf) >= REDIS_REQUEST_MAX_SIZE) {
+            redisLog(REDIS_VERBOSE, "Client protocol error");
+            freeClient(c);
+            return;
+        }
+    } else {
+        /* Bulk read handling. Note that if we are at this point
+           the client already sent a command terminated with a newline,
+           we are reading the bulk data that is actually the last
+           argument of the command. */
+        int qbl = sdslen(c->querybuf);
+
+        if (c->bulklen <= qbl) {
+            /* Copy everything but the final CRLF as final argument */
+            c->argv[c->argc] = createStringObject(c->querybuf,c->bulklen-2);
+            c->argc++;
+            c->querybuf = sdsrange(c->querybuf,c->bulklen,-1);
+            /* Process the command. If the client is still valid after
+             * the processing and there is more data in the buffer
+             * try to parse it. */
+            if (processCommand(c) && sdslen(c->querybuf)) goto again;
+            return;
+        }
+    }
+}
+
+void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mask) {
+    redisClient *c = (redisClient*) privdata;
+    char buf[REDIS_IOBUF_LEN];
+    int nread;
+    REDIS_NOTUSED(el);
+    REDIS_NOTUSED(mask);
+
+    nread = read(fd, buf, REDIS_IOBUF_LEN);
+    if (nread == -1) {
+        if (errno == EAGAIN) {
+            nread = 0;
+        } else {
+            redisLog(REDIS_VERBOSE, "Reading from client: %s",strerror(errno));
+            freeClient(c);
+            return;
+        }
+    } else if (nread == 0) {
+        redisLog(REDIS_VERBOSE, "Client closed connection");
+        freeClient(c);
+        return;
+    }
+    if (nread) {
+        c->querybuf = sdscatlen(c->querybuf, buf, nread);
+        c->lastinteraction = time(NULL);
+    } else {
+        return;
+    }
+    processInputBuffer(c);
+}

src/object.c

@@ -0,0 +1,405 @@
+#include "redis.h"
+#include <pthread.h>
+
+robj *createObject(int type, void *ptr) {
+    robj *o;
+
+    if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
+    if (listLength(server.objfreelist)) {
+        listNode *head = listFirst(server.objfreelist);
+        o = listNodeValue(head);
+        listDelNode(server.objfreelist,head);
+        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
+    } else {
+        if (server.vm_enabled)
+            pthread_mutex_unlock(&server.obj_freelist_mutex);
+        o = zmalloc(sizeof(*o));
+    }
+    o->type = type;
+    o->encoding = REDIS_ENCODING_RAW;
+    o->ptr = ptr;
+    o->refcount = 1;
+    if (server.vm_enabled) {
+        /* Note that this code may run in the context of an I/O thread
+         * and accessing server.lruclock in theory is an error
+         * (no locks). But in practice this is safe, and even if we read
+         * garbage Redis will not fail. */
+        o->lru = server.lruclock;
+        o->storage = REDIS_VM_MEMORY;
+    }
+    return o;
+}
+
+robj *createStringObject(char *ptr, size_t len) {
+    return createObject(REDIS_STRING,sdsnewlen(ptr,len));
+}
+
+robj *createStringObjectFromLongLong(long long value) {
+    robj *o;
+    if (value >= 0 && value < REDIS_SHARED_INTEGERS) {
+        incrRefCount(shared.integers[value]);
+        o = shared.integers[value];
+    } else {
+        if (value >= LONG_MIN && value <= LONG_MAX) {
+            o = createObject(REDIS_STRING, NULL);
+            o->encoding = REDIS_ENCODING_INT;
+            o->ptr = (void*)((long)value);
+        } else {
+            o = createObject(REDIS_STRING,sdsfromlonglong(value));
+        }
+    }
+    return o;
+}
+
+robj *dupStringObject(robj *o) {
+    redisAssert(o->encoding == REDIS_ENCODING_RAW);
+    return createStringObject(o->ptr,sdslen(o->ptr));
+}
+
+robj *createListObject(void) {
+    list *l = listCreate();
+    robj *o = createObject(REDIS_LIST,l);
+    listSetFreeMethod(l,decrRefCount);
+    o->encoding = REDIS_ENCODING_LINKEDLIST;
+    return o;
+}
+
+robj *createZiplistObject(void) {
+    unsigned char *zl = ziplistNew();
+    robj *o = createObject(REDIS_LIST,zl);
+    o->encoding = REDIS_ENCODING_ZIPLIST;
+    return o;
+}
+
+robj *createSetObject(void) {
+    dict *d = dictCreate(&setDictType,NULL);
+    return createObject(REDIS_SET,d);
+}
+
+robj *createHashObject(void) {
+    /* All the Hashes start as zipmaps. Will be automatically converted
+     * into hash tables if there are enough elements or big elements
+     * inside. */
+    unsigned char *zm = zipmapNew();
+    robj *o = createObject(REDIS_HASH,zm);
+    o->encoding = REDIS_ENCODING_ZIPMAP;
+    return o;
+}
+
+robj *createZsetObject(void) {
+    zset *zs = zmalloc(sizeof(*zs));
+
+    zs->dict = dictCreate(&zsetDictType,NULL);
+    zs->zsl = zslCreate();
+    return createObject(REDIS_ZSET,zs);
+}
+
+void freeStringObject(robj *o) {
+    if (o->encoding == REDIS_ENCODING_RAW) {
+        sdsfree(o->ptr);
+    }
+}
+
+void freeListObject(robj *o) {
+    switch (o->encoding) {
+    case REDIS_ENCODING_LINKEDLIST:
+        listRelease((list*) o->ptr);
+        break;
+    case REDIS_ENCODING_ZIPLIST:
+        zfree(o->ptr);
+        break;
+    default:
+        redisPanic("Unknown list encoding type");
+    }
+}
+
+void freeSetObject(robj *o) {
+    dictRelease((dict*) o->ptr);
+}
+
+void freeZsetObject(robj *o) {
+    zset *zs = o->ptr;
+
+    dictRelease(zs->dict);
+    zslFree(zs->zsl);
+    zfree(zs);
+}
+
+void freeHashObject(robj *o) {
+    switch (o->encoding) {
+    case REDIS_ENCODING_HT:
+        dictRelease((dict*) o->ptr);
+        break;
+    case REDIS_ENCODING_ZIPMAP:
+        zfree(o->ptr);
+        break;
+    default:
+        redisPanic("Unknown hash encoding type");
+        break;
+    }
+}
+
+void incrRefCount(robj *o) {
+    o->refcount++;
+}
+
+void decrRefCount(void *obj) {
+    robj *o = obj;
+
+    /* Object is a swapped out value, or in the process of being loaded. */
+    if (server.vm_enabled &&
+        (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING))
+    {
+        vmpointer *vp = obj;
+        if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(o);
+        vmMarkPagesFree(vp->page,vp->usedpages);
+        server.vm_stats_swapped_objects--;
+        zfree(vp);
+        return;
+    }
+
+    if (o->refcount <= 0) redisPanic("decrRefCount against refcount <= 0");
+    /* Object is in memory, or in the process of being swapped out.
+     *
+     * If the object is being swapped out, abort the operation on
+     * decrRefCount even if the refcount does not drop to 0: the object
+     * is referenced at least two times, as value of the key AND as
+     * job->val in the iojob. So if we don't invalidate the iojob, when it is
+     * done but the relevant key was removed in the meantime, the
+     * complete jobs handler will not find the key about the job and the
+     * assert will fail. */
+    if (server.vm_enabled && o->storage == REDIS_VM_SWAPPING)
+        vmCancelThreadedIOJob(o);
+    if (--(o->refcount) == 0) {
+        switch(o->type) {
+        case REDIS_STRING: freeStringObject(o); break;
+        case REDIS_LIST: freeListObject(o); break;
+        case REDIS_SET: freeSetObject(o); break;
+        case REDIS_ZSET: freeZsetObject(o); break;
+        case REDIS_HASH: freeHashObject(o); break;
+        default: redisPanic("Unknown object type"); break;
+        }
+        if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
+        if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX ||
+            !listAddNodeHead(server.objfreelist,o))
+            zfree(o);
+        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
+    }
+}
+
+int checkType(redisClient *c, robj *o, int type) {
+    if (o->type != type) {
+        addReply(c,shared.wrongtypeerr);
+        return 1;
+    }
+    return 0;
+}
+
+/* Try to encode a string object in order to save space */
+robj *tryObjectEncoding(robj *o) {
+    long value;
+    sds s = o->ptr;
+
+    if (o->encoding != REDIS_ENCODING_RAW)
+        return o; /* Already encoded */
+
+    /* It's not safe to encode shared objects: shared objects can be shared
+     * everywhere in the "object space" of Redis. Encoded objects can only
+     * appear as "values" (and not, for instance, as keys) */
+     if (o->refcount > 1) return o;
+
+    /* Currently we try to encode only strings */
+    redisAssert(o->type == REDIS_STRING);
+
+    /* Check if we can represent this string as a long integer */
+    if (isStringRepresentableAsLong(s,&value) == REDIS_ERR) return o;
+
+    /* Ok, this object can be encoded */
+    if (value >= 0 && value < REDIS_SHARED_INTEGERS) {
+        decrRefCount(o);
+        incrRefCount(shared.integers[value]);
+        return shared.integers[value];
+    } else {
+        o->encoding = REDIS_ENCODING_INT;
+        sdsfree(o->ptr);
+        o->ptr = (void*) value;
+        return o;
+    }
+}
+
+/* Get a decoded version of an encoded object (returned as a new object).
+ * If the object is already raw-encoded just increment the ref count. */
+robj *getDecodedObject(robj *o) {
+    robj *dec;
+
+    if (o->encoding == REDIS_ENCODING_RAW) {
+        incrRefCount(o);
+        return o;
+    }
+    if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
+        char buf[32];
+
+        ll2string(buf,32,(long)o->ptr);
+        dec = createStringObject(buf,strlen(buf));
+        return dec;
+    } else {
+        redisPanic("Unknown encoding type");
+    }
+}
+
+/* Compare two string objects via strcmp() or alike.
+ * Note that the objects may be integer-encoded. In such a case we
+ * use ll2string() to get a string representation of the numbers on the stack
+ * and compare the strings, it's much faster than calling getDecodedObject().
+ *
+ * Important note: if objects are not integer encoded, but binary-safe strings,
+ * sdscmp() from sds.c will apply memcmp() so this function ca be considered
+ * binary safe. */
+int compareStringObjects(robj *a, robj *b) {
+    redisAssert(a->type == REDIS_STRING && b->type == REDIS_STRING);
+    char bufa[128], bufb[128], *astr, *bstr;
+    int bothsds = 1;
+
+    if (a == b) return 0;
+    if (a->encoding != REDIS_ENCODING_RAW) {
+        ll2string(bufa,sizeof(bufa),(long) a->ptr);
+        astr = bufa;
+        bothsds = 0;
+    } else {
+        astr = a->ptr;
+    }
+    if (b->encoding != REDIS_ENCODING_RAW) {
+        ll2string(bufb,sizeof(bufb),(long) b->ptr);
+        bstr = bufb;
+        bothsds = 0;
+    } else {
+        bstr = b->ptr;
+    }
+    return bothsds ? sdscmp(astr,bstr) : strcmp(astr,bstr);
+}
+
+/* Equal string objects return 1 if the two objects are the same from the
+ * point of view of a string comparison, otherwise 0 is returned. Note that
+ * this function is faster then checking for (compareStringObject(a,b) == 0)
+ * because it can perform some more optimization. */
+int equalStringObjects(robj *a, robj *b) {
+    if (a->encoding != REDIS_ENCODING_RAW && b->encoding != REDIS_ENCODING_RAW){
+        return a->ptr == b->ptr;
+    } else {
+        return compareStringObjects(a,b) == 0;
+    }
+}
+
+size_t stringObjectLen(robj *o) {
+    redisAssert(o->type == REDIS_STRING);
+    if (o->encoding == REDIS_ENCODING_RAW) {
+        return sdslen(o->ptr);
+    } else {
+        char buf[32];
+
+        return ll2string(buf,32,(long)o->ptr);
+    }
+}
+
+int getDoubleFromObject(robj *o, double *target) {
+    double value;
+    char *eptr;
+
+    if (o == NULL) {
+        value = 0;
+    } else {
+        redisAssert(o->type == REDIS_STRING);
+        if (o->encoding == REDIS_ENCODING_RAW) {
+            value = strtod(o->ptr, &eptr);
+            if (eptr[0] != '\0') return REDIS_ERR;
+        } else if (o->encoding == REDIS_ENCODING_INT) {
+            value = (long)o->ptr;
+        } else {
+            redisPanic("Unknown string encoding");
+        }
+    }
+
+    *target = value;
+    return REDIS_OK;
+}
+
+int getDoubleFromObjectOrReply(redisClient *c, robj *o, double *target, const char *msg) {
+    double value;
+    if (getDoubleFromObject(o, &value) != REDIS_OK) {
+        if (msg != NULL) {
+            addReplySds(c, sdscatprintf(sdsempty(), "-ERR %s\r\n", msg));
+        } else {
+            addReplySds(c, sdsnew("-ERR value is not a double\r\n"));
+        }
+        return REDIS_ERR;
+    }
+
+    *target = value;
+    return REDIS_OK;
+}
+
+int getLongLongFromObject(robj *o, long long *target) {
+    long long value;
+    char *eptr;
+
+    if (o == NULL) {
+        value = 0;
+    } else {
+        redisAssert(o->type == REDIS_STRING);
+        if (o->encoding == REDIS_ENCODING_RAW) {
+            value = strtoll(o->ptr, &eptr, 10);
+            if (eptr[0] != '\0') return REDIS_ERR;
+        } else if (o->encoding == REDIS_ENCODING_INT) {
+            value = (long)o->ptr;
+        } else {
+            redisPanic("Unknown string encoding");
+        }
+    }
+
+    *target = value;
+    return REDIS_OK;
+}
+
+int getLongLongFromObjectOrReply(redisClient *c, robj *o, long long *target, const char *msg) {
+    long long value;
+    if (getLongLongFromObject(o, &value) != REDIS_OK) {
+        if (msg != NULL) {
+            addReplySds(c, sdscatprintf(sdsempty(), "-ERR %s\r\n", msg));
+        } else {
+            addReplySds(c, sdsnew("-ERR value is not an integer\r\n"));
+        }
+        return REDIS_ERR;
+    }
+
+    *target = value;
+    return REDIS_OK;
+}
+
+int getLongFromObjectOrReply(redisClient *c, robj *o, long *target, const char *msg) {
+    long long value;
+
+    if (getLongLongFromObjectOrReply(c, o, &value, msg) != REDIS_OK) return REDIS_ERR;
+    if (value < LONG_MIN || value > LONG_MAX) {
+        if (msg != NULL) {
+            addReplySds(c, sdscatprintf(sdsempty(), "-ERR %s\r\n", msg));
+        } else {
+            addReplySds(c, sdsnew("-ERR value is out of range\r\n"));
+        }
+        return REDIS_ERR;
+    }
+
+    *target = value;
+    return REDIS_OK;
+}
+
+char *strEncoding(int encoding) {
+    switch(encoding) {
+    case REDIS_ENCODING_RAW: return "raw";
+    case REDIS_ENCODING_INT: return "int";
+    case REDIS_ENCODING_HT: return "hashtable";
+    case REDIS_ENCODING_ZIPMAP: return "zipmap";
+    case REDIS_ENCODING_LINKEDLIST: return "linkedlist";
+    case REDIS_ENCODING_ZIPLIST: return "ziplist";
+    default: return "unknown";
+    }
+}

src/pubsub.c

@@ -0,0 +1,259 @@
+#include "redis.h"
+
+void freePubsubPattern(void *p) {
+    pubsubPattern *pat = p;
+
+    decrRefCount(pat->pattern);
+    zfree(pat);
+}
+
+int listMatchPubsubPattern(void *a, void *b) {
+    pubsubPattern *pa = a, *pb = b;
+
+    return (pa->client == pb->client) &&
+           (equalStringObjects(pa->pattern,pb->pattern));
+}
+
+/* Subscribe a client to a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was already subscribed to that channel. */
+int pubsubSubscribeChannel(redisClient *c, robj *channel) {
+    struct dictEntry *de;
+    list *clients = NULL;
+    int retval = 0;
+
+    /* Add the channel to the client -> channels hash table */
+    if (dictAdd(c->pubsub_channels,channel,NULL) == DICT_OK) {
+        retval = 1;
+        incrRefCount(channel);
+        /* Add the client to the channel -> list of clients hash table */
+        de = dictFind(server.pubsub_channels,channel);
+        if (de == NULL) {
+            clients = listCreate();
+            dictAdd(server.pubsub_channels,channel,clients);
+            incrRefCount(channel);
+        } else {
+            clients = dictGetEntryVal(de);
+        }
+        listAddNodeTail(clients,c);
+    }
+    /* Notify the client */
+    addReply(c,shared.mbulk3);
+    addReply(c,shared.subscribebulk);
+    addReplyBulk(c,channel);
+    addReplyLongLong(c,dictSize(c->pubsub_channels)+listLength(c->pubsub_patterns));
+    return retval;
+}
+
+/* Unsubscribe a client from a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was not subscribed to the specified channel. */
+int pubsubUnsubscribeChannel(redisClient *c, robj *channel, int notify) {
+    struct dictEntry *de;
+    list *clients;
+    listNode *ln;
+    int retval = 0;
+
+    /* Remove the channel from the client -> channels hash table */
+    incrRefCount(channel); /* channel may be just a pointer to the same object
+                            we have in the hash tables. Protect it... */
+    if (dictDelete(c->pubsub_channels,channel) == DICT_OK) {
+        retval = 1;
+        /* Remove the client from the channel -> clients list hash table */
+        de = dictFind(server.pubsub_channels,channel);
+        redisAssert(de != NULL);
+        clients = dictGetEntryVal(de);
+        ln = listSearchKey(clients,c);
+        redisAssert(ln != NULL);
+        listDelNode(clients,ln);
+        if (listLength(clients) == 0) {
+            /* Free the list and associated hash entry at all if this was
+             * the latest client, so that it will be possible to abuse
+             * Redis PUBSUB creating millions of channels. */
+            dictDelete(server.pubsub_channels,channel);
+        }
+    }
+    /* Notify the client */
+    if (notify) {
+        addReply(c,shared.mbulk3);
+        addReply(c,shared.unsubscribebulk);
+        addReplyBulk(c,channel);
+        addReplyLongLong(c,dictSize(c->pubsub_channels)+
+                       listLength(c->pubsub_patterns));
+
+    }
+    decrRefCount(channel); /* it is finally safe to release it */
+    return retval;
+}
+
+/* Subscribe a client to a pattern. Returns 1 if the operation succeeded, or 0 if the clinet was already subscribed to that pattern. */
+int pubsubSubscribePattern(redisClient *c, robj *pattern) {
+    int retval = 0;
+
+    if (listSearchKey(c->pubsub_patterns,pattern) == NULL) {
+        retval = 1;
+        pubsubPattern *pat;
+        listAddNodeTail(c->pubsub_patterns,pattern);
+        incrRefCount(pattern);
+        pat = zmalloc(sizeof(*pat));
+        pat->pattern = getDecodedObject(pattern);
+        pat->client = c;
+        listAddNodeTail(server.pubsub_patterns,pat);
+    }
+    /* Notify the client */
+    addReply(c,shared.mbulk3);
+    addReply(c,shared.psubscribebulk);
+    addReplyBulk(c,pattern);
+    addReplyLongLong(c,dictSize(c->pubsub_channels)+listLength(c->pubsub_patterns));
+    return retval;
+}
+
+/* Unsubscribe a client from a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was not subscribed to the specified channel. */
+int pubsubUnsubscribePattern(redisClient *c, robj *pattern, int notify) {
+    listNode *ln;
+    pubsubPattern pat;
+    int retval = 0;
+
+    incrRefCount(pattern); /* Protect the object. May be the same we remove */
+    if ((ln = listSearchKey(c->pubsub_patterns,pattern)) != NULL) {
+        retval = 1;
+        listDelNode(c->pubsub_patterns,ln);
+        pat.client = c;
+        pat.pattern = pattern;
+        ln = listSearchKey(server.pubsub_patterns,&pat);
+        listDelNode(server.pubsub_patterns,ln);
+    }
+    /* Notify the client */
+    if (notify) {
+        addReply(c,shared.mbulk3);
+        addReply(c,shared.punsubscribebulk);
+        addReplyBulk(c,pattern);
+        addReplyLongLong(c,dictSize(c->pubsub_channels)+
+                       listLength(c->pubsub_patterns));
+    }
+    decrRefCount(pattern);
+    return retval;
+}
+
+/* Unsubscribe from all the channels. Return the number of channels the
+ * client was subscribed from. */
+int pubsubUnsubscribeAllChannels(redisClient *c, int notify) {
+    dictIterator *di = dictGetIterator(c->pubsub_channels);
+    dictEntry *de;
+    int count = 0;
+
+    while((de = dictNext(di)) != NULL) {
+        robj *channel = dictGetEntryKey(de);
+
+        count += pubsubUnsubscribeChannel(c,channel,notify);
+    }
+    dictReleaseIterator(di);
+    return count;
+}
+
+/* Unsubscribe from all the patterns. Return the number of patterns the
+ * client was subscribed from. */
+int pubsubUnsubscribeAllPatterns(redisClient *c, int notify) {
+    listNode *ln;
+    listIter li;
+    int count = 0;
+
+    listRewind(c->pubsub_patterns,&li);
+    while ((ln = listNext(&li)) != NULL) {
+        robj *pattern = ln->value;
+
+        count += pubsubUnsubscribePattern(c,pattern,notify);
+    }
+    return count;
+}
+
+/* Publish a message */
+int pubsubPublishMessage(robj *channel, robj *message) {
+    int receivers = 0;
+    struct dictEntry *de;
+    listNode *ln;
+    listIter li;
+
+    /* Send to clients listening for that channel */
+    de = dictFind(server.pubsub_channels,channel);
+    if (de) {
+        list *list = dictGetEntryVal(de);
+        listNode *ln;
+        listIter li;
+
+        listRewind(list,&li);
+        while ((ln = listNext(&li)) != NULL) {
+            redisClient *c = ln->value;
+
+            addReply(c,shared.mbulk3);
+            addReply(c,shared.messagebulk);
+            addReplyBulk(c,channel);
+            addReplyBulk(c,message);
+            receivers++;
+        }
+    }
+    /* Send to clients listening to matching channels */
+    if (listLength(server.pubsub_patterns)) {
+        listRewind(server.pubsub_patterns,&li);
+        channel = getDecodedObject(channel);
+        while ((ln = listNext(&li)) != NULL) {
+            pubsubPattern *pat = ln->value;
+
+            if (stringmatchlen((char*)pat->pattern->ptr,
+                                sdslen(pat->pattern->ptr),
+                                (char*)channel->ptr,
+                                sdslen(channel->ptr),0)) {
+                addReply(pat->client,shared.mbulk4);
+                addReply(pat->client,shared.pmessagebulk);
+                addReplyBulk(pat->client,pat->pattern);
+                addReplyBulk(pat->client,channel);
+                addReplyBulk(pat->client,message);
+                receivers++;
+            }
+        }
+        decrRefCount(channel);
+    }
+    return receivers;
+}
+
+void subscribeCommand(redisClient *c) {
+    int j;
+
+    for (j = 1; j < c->argc; j++)
+        pubsubSubscribeChannel(c,c->argv[j]);
+}
+
+void unsubscribeCommand(redisClient *c) {
+    if (c->argc == 1) {
+        pubsubUnsubscribeAllChannels(c,1);
+        return;
+    } else {
+        int j;
+
+        for (j = 1; j < c->argc; j++)
+            pubsubUnsubscribeChannel(c,c->argv[j],1);
+    }
+}
+
+void psubscribeCommand(redisClient *c) {
+    int j;
+
+    for (j = 1; j < c->argc; j++)
+        pubsubSubscribePattern(c,c->argv[j]);
+}
+
+void punsubscribeCommand(redisClient *c) {
+    if (c->argc == 1) {
+        pubsubUnsubscribeAllPatterns(c,1);
+        return;
+    } else {
+        int j;
+
+        for (j = 1; j < c->argc; j++)
+            pubsubUnsubscribePattern(c,c->argv[j],1);
+    }
+}
+
+void publishCommand(redisClient *c) {
+    int receivers = pubsubPublishMessage(c->argv[1],c->argv[2]);
+    addReplyLongLong(c,receivers);
+}

src/rdb.c

@@ -0,0 +1,886 @@
+#include "redis.h"
+#include "lzf.h"    /* LZF compression library */
+
+#include <math.h>
+
+int rdbSaveType(FILE *fp, unsigned char type) {
+    if (fwrite(&type,1,1,fp) == 0) return -1;
+    return 0;
+}
+
+int rdbSaveTime(FILE *fp, time_t t) {
+    int32_t t32 = (int32_t) t;
+    if (fwrite(&t32,4,1,fp) == 0) return -1;
+    return 0;
+}
+
+/* check rdbLoadLen() comments for more info */
+int rdbSaveLen(FILE *fp, uint32_t len) {
+    unsigned char buf[2];
+
+    if (len < (1<<6)) {
+        /* Save a 6 bit len */
+        buf[0] = (len&0xFF)|(REDIS_RDB_6BITLEN<<6);
+        if (fwrite(buf,1,1,fp) == 0) return -1;
+    } else if (len < (1<<14)) {
+        /* Save a 14 bit len */
+        buf[0] = ((len>>8)&0xFF)|(REDIS_RDB_14BITLEN<<6);
+        buf[1] = len&0xFF;
+        if (fwrite(buf,2,1,fp) == 0) return -1;
+    } else {
+        /* Save a 32 bit len */
+        buf[0] = (REDIS_RDB_32BITLEN<<6);
+        if (fwrite(buf,1,1,fp) == 0) return -1;
+        len = htonl(len);
+        if (fwrite(&len,4,1,fp) == 0) return -1;
+    }
+    return 0;
+}
+
+/* Encode 'value' as an integer if possible (if integer will fit the
+ * supported range). If the function sucessful encoded the integer
+ * then the (up to 5 bytes) encoded representation is written in the
+ * string pointed by 'enc' and the length is returned. Otherwise
+ * 0 is returned. */
+int rdbEncodeInteger(long long value, unsigned char *enc) {
+    /* Finally check if it fits in our ranges */
+    if (value >= -(1<<7) && value <= (1<<7)-1) {
+        enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT8;
+        enc[1] = value&0xFF;
+        return 2;
+    } else if (value >= -(1<<15) && value <= (1<<15)-1) {
+        enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT16;
+        enc[1] = value&0xFF;
+        enc[2] = (value>>8)&0xFF;
+        return 3;
+    } else if (value >= -((long long)1<<31) && value <= ((long long)1<<31)-1) {
+        enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT32;
+        enc[1] = value&0xFF;
+        enc[2] = (value>>8)&0xFF;
+        enc[3] = (value>>16)&0xFF;
+        enc[4] = (value>>24)&0xFF;
+        return 5;
+    } else {
+        return 0;
+    }
+}
+
+/* String objects in the form "2391" "-100" without any space and with a
+ * range of values that can fit in an 8, 16 or 32 bit signed value can be
+ * encoded as integers to save space */
+int rdbTryIntegerEncoding(char *s, size_t len, unsigned char *enc) {
+    long long value;
+    char *endptr, buf[32];
+
+    /* Check if it's possible to encode this value as a number */
+    value = strtoll(s, &endptr, 10);
+    if (endptr[0] != '\0') return 0;
+    ll2string(buf,32,value);
+
+    /* If the number converted back into a string is not identical
+     * then it's not possible to encode the string as integer */
+    if (strlen(buf) != len || memcmp(buf,s,len)) return 0;
+
+    return rdbEncodeInteger(value,enc);
+}
+
+int rdbSaveLzfStringObject(FILE *fp, unsigned char *s, size_t len) {
+    size_t comprlen, outlen;
+    unsigned char byte;
+    void *out;
+
+    /* We require at least four bytes compression for this to be worth it */
+    if (len <= 4) return 0;
+    outlen = len-4;
+    if ((out = zmalloc(outlen+1)) == NULL) return 0;
+    comprlen = lzf_compress(s, len, out, outlen);
+    if (comprlen == 0) {
+        zfree(out);
+        return 0;
+    }
+    /* Data compressed! Let's save it on disk */
+    byte = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_LZF;
+    if (fwrite(&byte,1,1,fp) == 0) goto writeerr;
+    if (rdbSaveLen(fp,comprlen) == -1) goto writeerr;
+    if (rdbSaveLen(fp,len) == -1) goto writeerr;
+    if (fwrite(out,comprlen,1,fp) == 0) goto writeerr;
+    zfree(out);
+    return comprlen;
+
+writeerr:
+    zfree(out);
+    return -1;
+}
+
+/* Save a string objet as [len][data] on disk. If the object is a string
+ * representation of an integer value we try to safe it in a special form */
+int rdbSaveRawString(FILE *fp, unsigned char *s, size_t len) {
+    int enclen;
+
+    /* Try integer encoding */
+    if (len <= 11) {
+        unsigned char buf[5];
+        if ((enclen = rdbTryIntegerEncoding((char*)s,len,buf)) > 0) {
+            if (fwrite(buf,enclen,1,fp) == 0) return -1;
+            return 0;
+        }
+    }
+
+    /* Try LZF compression - under 20 bytes it's unable to compress even
+     * aaaaaaaaaaaaaaaaaa so skip it */
+    if (server.rdbcompression && len > 20) {
+        int retval;
+
+        retval = rdbSaveLzfStringObject(fp,s,len);
+        if (retval == -1) return -1;
+        if (retval > 0) return 0;
+        /* retval == 0 means data can't be compressed, save the old way */
+    }
+
+    /* Store verbatim */
+    if (rdbSaveLen(fp,len) == -1) return -1;
+    if (len && fwrite(s,len,1,fp) == 0) return -1;
+    return 0;
+}
+
+/* Save a long long value as either an encoded string or a string. */
+int rdbSaveLongLongAsStringObject(FILE *fp, long long value) {
+    unsigned char buf[32];
+    int enclen = rdbEncodeInteger(value,buf);
+    if (enclen > 0) {
+        if (fwrite(buf,enclen,1,fp) == 0) return -1;
+    } else {
+        /* Encode as string */
+        enclen = ll2string((char*)buf,32,value);
+        redisAssert(enclen < 32);
+        if (rdbSaveLen(fp,enclen) == -1) return -1;
+        if (fwrite(buf,enclen,1,fp) == 0) return -1;
+    }
+    return 0;
+}
+
+/* Like rdbSaveStringObjectRaw() but handle encoded objects */
+int rdbSaveStringObject(FILE *fp, robj *obj) {
+    /* Avoid to decode the object, then encode it again, if the
+     * object is alrady integer encoded. */
+    if (obj->encoding == REDIS_ENCODING_INT) {
+        return rdbSaveLongLongAsStringObject(fp,(long)obj->ptr);
+    } else {
+        redisAssert(obj->encoding == REDIS_ENCODING_RAW);
+        return rdbSaveRawString(fp,obj->ptr,sdslen(obj->ptr));
+    }
+}
+
+/* Save a double value. Doubles are saved as strings prefixed by an unsigned
+ * 8 bit integer specifing the length of the representation.
+ * This 8 bit integer has special values in order to specify the following
+ * conditions:
+ * 253: not a number
+ * 254: + inf
+ * 255: - inf
+ */
+int rdbSaveDoubleValue(FILE *fp, double val) {
+    unsigned char buf[128];
+    int len;
+
+    if (isnan(val)) {
+        buf[0] = 253;
+        len = 1;
+    } else if (!isfinite(val)) {
+        len = 1;
+        buf[0] = (val < 0) ? 255 : 254;
+    } else {
+#if (DBL_MANT_DIG >= 52) && (LLONG_MAX == 0x7fffffffffffffffLL)
+        /* Check if the float is in a safe range to be casted into a
+         * long long. We are assuming that long long is 64 bit here.
+         * Also we are assuming that there are no implementations around where
+         * double has precision < 52 bit.
+         *
+         * Under this assumptions we test if a double is inside an interval
+         * where casting to long long is safe. Then using two castings we
+         * make sure the decimal part is zero. If all this is true we use
+         * integer printing function that is much faster. */
+        double min = -4503599627370495; /* (2^52)-1 */
+        double max = 4503599627370496; /* -(2^52) */
+        if (val > min && val < max && val == ((double)((long long)val)))
+            ll2string((char*)buf+1,sizeof(buf),(long long)val);
+        else
+#endif
+            snprintf((char*)buf+1,sizeof(buf)-1,"%.17g",val);
+        buf[0] = strlen((char*)buf+1);
+        len = buf[0]+1;
+    }
+    if (fwrite(buf,len,1,fp) == 0) return -1;
+    return 0;
+}
+
+/* Save a Redis object. */
+int rdbSaveObject(FILE *fp, robj *o) {
+    if (o->type == REDIS_STRING) {
+        /* Save a string value */
+        if (rdbSaveStringObject(fp,o) == -1) return -1;
+    } else if (o->type == REDIS_LIST) {
+        /* Save a list value */
+        if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+            unsigned char *p;
+            unsigned char *vstr;
+            unsigned int vlen;
+            long long vlong;
+
+            if (rdbSaveLen(fp,ziplistLen(o->ptr)) == -1) return -1;
+            p = ziplistIndex(o->ptr,0);
+            while(ziplistGet(p,&vstr,&vlen,&vlong)) {
+                if (vstr) {
+                    if (rdbSaveRawString(fp,vstr,vlen) == -1)
+                        return -1;
+                } else {
+                    if (rdbSaveLongLongAsStringObject(fp,vlong) == -1)
+                        return -1;
+                }
+                p = ziplistNext(o->ptr,p);
+            }
+        } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+            list *list = o->ptr;
+            listIter li;
+            listNode *ln;
+
+            if (rdbSaveLen(fp,listLength(list)) == -1) return -1;
+            listRewind(list,&li);
+            while((ln = listNext(&li))) {
+                robj *eleobj = listNodeValue(ln);
+                if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+            }
+        } else {
+            redisPanic("Unknown list encoding");
+        }
+    } else if (o->type == REDIS_SET) {
+        /* Save a set value */
+        dict *set = o->ptr;
+        dictIterator *di = dictGetIterator(set);
+        dictEntry *de;
+
+        if (rdbSaveLen(fp,dictSize(set)) == -1) return -1;
+        while((de = dictNext(di)) != NULL) {
+            robj *eleobj = dictGetEntryKey(de);
+
+            if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+        }
+        dictReleaseIterator(di);
+    } else if (o->type == REDIS_ZSET) {
+        /* Save a set value */
+        zset *zs = o->ptr;
+        dictIterator *di = dictGetIterator(zs->dict);
+        dictEntry *de;
+
+        if (rdbSaveLen(fp,dictSize(zs->dict)) == -1) return -1;
+        while((de = dictNext(di)) != NULL) {
+            robj *eleobj = dictGetEntryKey(de);
+            double *score = dictGetEntryVal(de);
+
+            if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+            if (rdbSaveDoubleValue(fp,*score) == -1) return -1;
+        }
+        dictReleaseIterator(di);
+    } else if (o->type == REDIS_HASH) {
+        /* Save a hash value */
+        if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+            unsigned char *p = zipmapRewind(o->ptr);
+            unsigned int count = zipmapLen(o->ptr);
+            unsigned char *key, *val;
+            unsigned int klen, vlen;
+
+            if (rdbSaveLen(fp,count) == -1) return -1;
+            while((p = zipmapNext(p,&key,&klen,&val,&vlen)) != NULL) {
+                if (rdbSaveRawString(fp,key,klen) == -1) return -1;
+                if (rdbSaveRawString(fp,val,vlen) == -1) return -1;
+            }
+        } else {
+            dictIterator *di = dictGetIterator(o->ptr);
+            dictEntry *de;
+
+            if (rdbSaveLen(fp,dictSize((dict*)o->ptr)) == -1) return -1;
+            while((de = dictNext(di)) != NULL) {
+                robj *key = dictGetEntryKey(de);
+                robj *val = dictGetEntryVal(de);
+
+                if (rdbSaveStringObject(fp,key) == -1) return -1;
+                if (rdbSaveStringObject(fp,val) == -1) return -1;
+            }
+            dictReleaseIterator(di);
+        }
+    } else {
+        redisPanic("Unknown object type");
+    }
+    return 0;
+}
+
+/* Return the length the object will have on disk if saved with
+ * the rdbSaveObject() function. Currently we use a trick to get
+ * this length with very little changes to the code. In the future
+ * we could switch to a faster solution. */
+off_t rdbSavedObjectLen(robj *o, FILE *fp) {
+    if (fp == NULL) fp = server.devnull;
+    rewind(fp);
+    redisAssert(rdbSaveObject(fp,o) != 1);
+    return ftello(fp);
+}
+
+/* Return the number of pages required to save this object in the swap file */
+off_t rdbSavedObjectPages(robj *o, FILE *fp) {
+    off_t bytes = rdbSavedObjectLen(o,fp);
+
+    return (bytes+(server.vm_page_size-1))/server.vm_page_size;
+}
+
+/* Save the DB on disk. Return REDIS_ERR on error, REDIS_OK on success */
+int rdbSave(char *filename) {
+    dictIterator *di = NULL;
+    dictEntry *de;
+    FILE *fp;
+    char tmpfile[256];
+    int j;
+    time_t now = time(NULL);
+
+    /* Wait for I/O therads to terminate, just in case this is a
+     * foreground-saving, to avoid seeking the swap file descriptor at the
+     * same time. */
+    if (server.vm_enabled)
+        waitEmptyIOJobsQueue();
+
+    snprintf(tmpfile,256,"temp-%d.rdb", (int) getpid());
+    fp = fopen(tmpfile,"w");
+    if (!fp) {
+        redisLog(REDIS_WARNING, "Failed saving the DB: %s", strerror(errno));
+        return REDIS_ERR;
+    }
+    if (fwrite("REDIS0001",9,1,fp) == 0) goto werr;
+    for (j = 0; j < server.dbnum; j++) {
+        redisDb *db = server.db+j;
+        dict *d = db->dict;
+        if (dictSize(d) == 0) continue;
+        di = dictGetIterator(d);
+        if (!di) {
+            fclose(fp);
+            return REDIS_ERR;
+        }
+
+        /* Write the SELECT DB opcode */
+        if (rdbSaveType(fp,REDIS_SELECTDB) == -1) goto werr;
+        if (rdbSaveLen(fp,j) == -1) goto werr;
+
+        /* Iterate this DB writing every entry */
+        while((de = dictNext(di)) != NULL) {
+            sds keystr = dictGetEntryKey(de);
+            robj key, *o = dictGetEntryVal(de);
+            time_t expiretime;
+            
+            initStaticStringObject(key,keystr);
+            expiretime = getExpire(db,&key);
+
+            /* Save the expire time */
+            if (expiretime != -1) {
+                /* If this key is already expired skip it */
+                if (expiretime < now) continue;
+                if (rdbSaveType(fp,REDIS_EXPIRETIME) == -1) goto werr;
+                if (rdbSaveTime(fp,expiretime) == -1) goto werr;
+            }
+            /* Save the key and associated value. This requires special
+             * handling if the value is swapped out. */
+            if (!server.vm_enabled || o->storage == REDIS_VM_MEMORY ||
+                                      o->storage == REDIS_VM_SWAPPING) {
+                /* Save type, key, value */
+                if (rdbSaveType(fp,o->type) == -1) goto werr;
+                if (rdbSaveStringObject(fp,&key) == -1) goto werr;
+                if (rdbSaveObject(fp,o) == -1) goto werr;
+            } else {
+                /* REDIS_VM_SWAPPED or REDIS_VM_LOADING */
+                robj *po;
+                /* Get a preview of the object in memory */
+                po = vmPreviewObject(o);
+                /* Save type, key, value */
+                if (rdbSaveType(fp,po->type) == -1) goto werr;
+                if (rdbSaveStringObject(fp,&key) == -1) goto werr;
+                if (rdbSaveObject(fp,po) == -1) goto werr;
+                /* Remove the loaded object from memory */
+                decrRefCount(po);
+            }
+        }
+        dictReleaseIterator(di);
+    }
+    /* EOF opcode */
+    if (rdbSaveType(fp,REDIS_EOF) == -1) goto werr;
+
+    /* Make sure data will not remain on the OS's output buffers */
+    fflush(fp);
+    fsync(fileno(fp));
+    fclose(fp);
+
+    /* Use RENAME to make sure the DB file is changed atomically only
+     * if the generate DB file is ok. */
+    if (rename(tmpfile,filename) == -1) {
+        redisLog(REDIS_WARNING,"Error moving temp DB file on the final destination: %s", strerror(errno));
+        unlink(tmpfile);
+        return REDIS_ERR;
+    }
+    redisLog(REDIS_NOTICE,"DB saved on disk");
+    server.dirty = 0;
+    server.lastsave = time(NULL);
+    return REDIS_OK;
+
+werr:
+    fclose(fp);
+    unlink(tmpfile);
+    redisLog(REDIS_WARNING,"Write error saving DB on disk: %s", strerror(errno));
+    if (di) dictReleaseIterator(di);
+    return REDIS_ERR;
+}
+
+int rdbSaveBackground(char *filename) {
+    pid_t childpid;
+
+    if (server.bgsavechildpid != -1) return REDIS_ERR;
+    if (server.vm_enabled) waitEmptyIOJobsQueue();
+    if ((childpid = fork()) == 0) {
+        /* Child */
+        if (server.vm_enabled) vmReopenSwapFile();
+        close(server.fd);
+        if (rdbSave(filename) == REDIS_OK) {
+            _exit(0);
+        } else {
+            _exit(1);
+        }
+    } else {
+        /* Parent */
+        if (childpid == -1) {
+            redisLog(REDIS_WARNING,"Can't save in background: fork: %s",
+                strerror(errno));
+            return REDIS_ERR;
+        }
+        redisLog(REDIS_NOTICE,"Background saving started by pid %d",childpid);
+        server.bgsavechildpid = childpid;
+        updateDictResizePolicy();
+        return REDIS_OK;
+    }
+    return REDIS_OK; /* unreached */
+}
+
+void rdbRemoveTempFile(pid_t childpid) {
+    char tmpfile[256];
+
+    snprintf(tmpfile,256,"temp-%d.rdb", (int) childpid);
+    unlink(tmpfile);
+}
+
+int rdbLoadType(FILE *fp) {
+    unsigned char type;
+    if (fread(&type,1,1,fp) == 0) return -1;
+    return type;
+}
+
+time_t rdbLoadTime(FILE *fp) {
+    int32_t t32;
+    if (fread(&t32,4,1,fp) == 0) return -1;
+    return (time_t) t32;
+}
+
+/* Load an encoded length from the DB, see the REDIS_RDB_* defines on the top
+ * of this file for a description of how this are stored on disk.
+ *
+ * isencoded is set to 1 if the readed length is not actually a length but
+ * an "encoding type", check the above comments for more info */
+uint32_t rdbLoadLen(FILE *fp, int *isencoded) {
+    unsigned char buf[2];
+    uint32_t len;
+    int type;
+
+    if (isencoded) *isencoded = 0;
+    if (fread(buf,1,1,fp) == 0) return REDIS_RDB_LENERR;
+    type = (buf[0]&0xC0)>>6;
+    if (type == REDIS_RDB_6BITLEN) {
+        /* Read a 6 bit len */
+        return buf[0]&0x3F;
+    } else if (type == REDIS_RDB_ENCVAL) {
+        /* Read a 6 bit len encoding type */
+        if (isencoded) *isencoded = 1;
+        return buf[0]&0x3F;
+    } else if (type == REDIS_RDB_14BITLEN) {
+        /* Read a 14 bit len */
+        if (fread(buf+1,1,1,fp) == 0) return REDIS_RDB_LENERR;
+        return ((buf[0]&0x3F)<<8)|buf[1];
+    } else {
+        /* Read a 32 bit len */
+        if (fread(&len,4,1,fp) == 0) return REDIS_RDB_LENERR;
+        return ntohl(len);
+    }
+}
+
+/* Load an integer-encoded object from file 'fp', with the specified
+ * encoding type 'enctype'. If encode is true the function may return
+ * an integer-encoded object as reply, otherwise the returned object
+ * will always be encoded as a raw string. */
+robj *rdbLoadIntegerObject(FILE *fp, int enctype, int encode) {
+    unsigned char enc[4];
+    long long val;
+
+    if (enctype == REDIS_RDB_ENC_INT8) {
+        if (fread(enc,1,1,fp) == 0) return NULL;
+        val = (signed char)enc[0];
+    } else if (enctype == REDIS_RDB_ENC_INT16) {
+        uint16_t v;
+        if (fread(enc,2,1,fp) == 0) return NULL;
+        v = enc[0]|(enc[1]<<8);
+        val = (int16_t)v;
+    } else if (enctype == REDIS_RDB_ENC_INT32) {
+        uint32_t v;
+        if (fread(enc,4,1,fp) == 0) return NULL;
+        v = enc[0]|(enc[1]<<8)|(enc[2]<<16)|(enc[3]<<24);
+        val = (int32_t)v;
+    } else {
+        val = 0; /* anti-warning */
+        redisPanic("Unknown RDB integer encoding type");
+    }
+    if (encode)
+        return createStringObjectFromLongLong(val);
+    else
+        return createObject(REDIS_STRING,sdsfromlonglong(val));
+}
+
+robj *rdbLoadLzfStringObject(FILE*fp) {
+    unsigned int len, clen;
+    unsigned char *c = NULL;
+    sds val = NULL;
+
+    if ((clen = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+    if ((len = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+    if ((c = zmalloc(clen)) == NULL) goto err;
+    if ((val = sdsnewlen(NULL,len)) == NULL) goto err;
+    if (fread(c,clen,1,fp) == 0) goto err;
+    if (lzf_decompress(c,clen,val,len) == 0) goto err;
+    zfree(c);
+    return createObject(REDIS_STRING,val);
+err:
+    zfree(c);
+    sdsfree(val);
+    return NULL;
+}
+
+robj *rdbGenericLoadStringObject(FILE*fp, int encode) {
+    int isencoded;
+    uint32_t len;
+    sds val;
+
+    len = rdbLoadLen(fp,&isencoded);
+    if (isencoded) {
+        switch(len) {
+        case REDIS_RDB_ENC_INT8:
+        case REDIS_RDB_ENC_INT16:
+        case REDIS_RDB_ENC_INT32:
+            return rdbLoadIntegerObject(fp,len,encode);
+        case REDIS_RDB_ENC_LZF:
+            return rdbLoadLzfStringObject(fp);
+        default:
+            redisPanic("Unknown RDB encoding type");
+        }
+    }
+
+    if (len == REDIS_RDB_LENERR) return NULL;
+    val = sdsnewlen(NULL,len);
+    if (len && fread(val,len,1,fp) == 0) {
+        sdsfree(val);
+        return NULL;
+    }
+    return createObject(REDIS_STRING,val);
+}
+
+robj *rdbLoadStringObject(FILE *fp) {
+    return rdbGenericLoadStringObject(fp,0);
+}
+
+robj *rdbLoadEncodedStringObject(FILE *fp) {
+    return rdbGenericLoadStringObject(fp,1);
+}
+
+/* For information about double serialization check rdbSaveDoubleValue() */
+int rdbLoadDoubleValue(FILE *fp, double *val) {
+    char buf[128];
+    unsigned char len;
+
+    if (fread(&len,1,1,fp) == 0) return -1;
+    switch(len) {
+    case 255: *val = R_NegInf; return 0;
+    case 254: *val = R_PosInf; return 0;
+    case 253: *val = R_Nan; return 0;
+    default:
+        if (fread(buf,len,1,fp) == 0) return -1;
+        buf[len] = '\0';
+        sscanf(buf, "%lg", val);
+        return 0;
+    }
+}
+
+/* Load a Redis object of the specified type from the specified file.
+ * On success a newly allocated object is returned, otherwise NULL. */
+robj *rdbLoadObject(int type, FILE *fp) {
+    robj *o, *ele, *dec;
+    size_t len;
+
+    redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",type,ftell(fp));
+    if (type == REDIS_STRING) {
+        /* Read string value */
+        if ((o = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+        o = tryObjectEncoding(o);
+    } else if (type == REDIS_LIST) {
+        /* Read list value */
+        if ((len = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+
+        /* Use a real list when there are too many entries */
+        if (len > server.list_max_ziplist_entries) {
+            o = createListObject();
+        } else {
+            o = createZiplistObject();
+        }
+
+        /* Load every single element of the list */
+        while(len--) {
+            if ((ele = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+
+            /* If we are using a ziplist and the value is too big, convert
+             * the object to a real list. */
+            if (o->encoding == REDIS_ENCODING_ZIPLIST &&
+                ele->encoding == REDIS_ENCODING_RAW &&
+                sdslen(ele->ptr) > server.list_max_ziplist_value)
+                    listTypeConvert(o,REDIS_ENCODING_LINKEDLIST);
+
+            if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+                dec = getDecodedObject(ele);
+                o->ptr = ziplistPush(o->ptr,dec->ptr,sdslen(dec->ptr),REDIS_TAIL);
+                decrRefCount(dec);
+                decrRefCount(ele);
+            } else {
+                ele = tryObjectEncoding(ele);
+                listAddNodeTail(o->ptr,ele);
+            }
+        }
+    } else if (type == REDIS_SET) {
+        /* Read list/set value */
+        if ((len = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+        o = createSetObject();
+        /* It's faster to expand the dict to the right size asap in order
+         * to avoid rehashing */
+        if (len > DICT_HT_INITIAL_SIZE)
+            dictExpand(o->ptr,len);
+        /* Load every single element of the list/set */
+        while(len--) {
+            if ((ele = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+            ele = tryObjectEncoding(ele);
+            dictAdd((dict*)o->ptr,ele,NULL);
+        }
+    } else if (type == REDIS_ZSET) {
+        /* Read list/set value */
+        size_t zsetlen;
+        zset *zs;
+
+        if ((zsetlen = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+        o = createZsetObject();
+        zs = o->ptr;
+        /* Load every single element of the list/set */
+        while(zsetlen--) {
+            robj *ele;
+            double *score = zmalloc(sizeof(double));
+
+            if ((ele = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+            ele = tryObjectEncoding(ele);
+            if (rdbLoadDoubleValue(fp,score) == -1) return NULL;
+            dictAdd(zs->dict,ele,score);
+            zslInsert(zs->zsl,*score,ele);
+            incrRefCount(ele); /* added to skiplist */
+        }
+    } else if (type == REDIS_HASH) {
+        size_t hashlen;
+
+        if ((hashlen = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+        o = createHashObject();
+        /* Too many entries? Use an hash table. */
+        if (hashlen > server.hash_max_zipmap_entries)
+            convertToRealHash(o);
+        /* Load every key/value, then set it into the zipmap or hash
+         * table, as needed. */
+        while(hashlen--) {
+            robj *key, *val;
+
+            if ((key = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+            if ((val = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
+            /* If we are using a zipmap and there are too big values
+             * the object is converted to real hash table encoding. */
+            if (o->encoding != REDIS_ENCODING_HT &&
+               ((key->encoding == REDIS_ENCODING_RAW &&
+                sdslen(key->ptr) > server.hash_max_zipmap_value) ||
+                (val->encoding == REDIS_ENCODING_RAW &&
+                sdslen(val->ptr) > server.hash_max_zipmap_value)))
+            {
+                    convertToRealHash(o);
+            }
+
+            if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+                unsigned char *zm = o->ptr;
+                robj *deckey, *decval;
+
+                /* We need raw string objects to add them to the zipmap */
+                deckey = getDecodedObject(key);
+                decval = getDecodedObject(val);
+                zm = zipmapSet(zm,deckey->ptr,sdslen(deckey->ptr),
+                                  decval->ptr,sdslen(decval->ptr),NULL);
+                o->ptr = zm;
+                decrRefCount(deckey);
+                decrRefCount(decval);
+                decrRefCount(key);
+                decrRefCount(val);
+            } else {
+                key = tryObjectEncoding(key);
+                val = tryObjectEncoding(val);
+                dictAdd((dict*)o->ptr,key,val);
+            }
+        }
+    } else {
+        redisPanic("Unknown object type");
+    }
+    return o;
+}
+
+int rdbLoad(char *filename) {
+    FILE *fp;
+    uint32_t dbid;
+    int type, retval, rdbver;
+    int swap_all_values = 0;
+    redisDb *db = server.db+0;
+    char buf[1024];
+    time_t expiretime, now = time(NULL);
+
+    fp = fopen(filename,"r");
+    if (!fp) return REDIS_ERR;
+    if (fread(buf,9,1,fp) == 0) goto eoferr;
+    buf[9] = '\0';
+    if (memcmp(buf,"REDIS",5) != 0) {
+        fclose(fp);
+        redisLog(REDIS_WARNING,"Wrong signature trying to load DB from file");
+        return REDIS_ERR;
+    }
+    rdbver = atoi(buf+5);
+    if (rdbver != 1) {
+        fclose(fp);
+        redisLog(REDIS_WARNING,"Can't handle RDB format version %d",rdbver);
+        return REDIS_ERR;
+    }
+    while(1) {
+        robj *key, *val;
+        int force_swapout;
+
+        expiretime = -1;
+        /* Read type. */
+        if ((type = rdbLoadType(fp)) == -1) goto eoferr;
+        if (type == REDIS_EXPIRETIME) {
+            if ((expiretime = rdbLoadTime(fp)) == -1) goto eoferr;
+            /* We read the time so we need to read the object type again */
+            if ((type = rdbLoadType(fp)) == -1) goto eoferr;
+        }
+        if (type == REDIS_EOF) break;
+        /* Handle SELECT DB opcode as a special case */
+        if (type == REDIS_SELECTDB) {
+            if ((dbid = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR)
+                goto eoferr;
+            if (dbid >= (unsigned)server.dbnum) {
+                redisLog(REDIS_WARNING,"FATAL: Data file was created with a Redis server configured to handle more than %d databases. Exiting\n", server.dbnum);
+                exit(1);
+            }
+            db = server.db+dbid;
+            continue;
+        }
+        /* Read key */
+        if ((key = rdbLoadStringObject(fp)) == NULL) goto eoferr;
+        /* Read value */
+        if ((val = rdbLoadObject(type,fp)) == NULL) goto eoferr;
+        /* Check if the key already expired */
+        if (expiretime != -1 && expiretime < now) {
+            decrRefCount(key);
+            decrRefCount(val);
+            continue;
+        }
+        /* Add the new object in the hash table */
+        retval = dbAdd(db,key,val);
+        if (retval == REDIS_ERR) {
+            redisLog(REDIS_WARNING,"Loading DB, duplicated key (%s) found! Unrecoverable error, exiting now.", key->ptr);
+            exit(1);
+        }
+        /* Set the expire time if needed */
+        if (expiretime != -1) setExpire(db,key,expiretime);
+
+        /* Handle swapping while loading big datasets when VM is on */
+
+        /* If we detecter we are hopeless about fitting something in memory
+         * we just swap every new key on disk. Directly...
+         * Note that's important to check for this condition before resorting
+         * to random sampling, otherwise we may try to swap already
+         * swapped keys. */
+        if (swap_all_values) {
+            dictEntry *de = dictFind(db->dict,key->ptr);
+
+            /* de may be NULL since the key already expired */
+            if (de) {
+                vmpointer *vp;
+                val = dictGetEntryVal(de);
+
+                if (val->refcount == 1 &&
+                    (vp = vmSwapObjectBlocking(val)) != NULL)
+                    dictGetEntryVal(de) = vp;
+            }
+            decrRefCount(key);
+            continue;
+        }
+        decrRefCount(key);
+
+        /* Flush data on disk once 32 MB of additional RAM are used... */
+        force_swapout = 0;
+        if ((zmalloc_used_memory() - server.vm_max_memory) > 1024*1024*32)
+            force_swapout = 1;
+
+        /* If we have still some hope of having some value fitting memory
+         * then we try random sampling. */
+        if (!swap_all_values && server.vm_enabled && force_swapout) {
+            while (zmalloc_used_memory() > server.vm_max_memory) {
+                if (vmSwapOneObjectBlocking() == REDIS_ERR) break;
+            }
+            if (zmalloc_used_memory() > server.vm_max_memory)
+                swap_all_values = 1; /* We are already using too much mem */
+        }
+    }
+    fclose(fp);
+    return REDIS_OK;
+
+eoferr: /* unexpected end of file is handled here with a fatal exit */
+    redisLog(REDIS_WARNING,"Short read or OOM loading DB. Unrecoverable error, aborting now.");
+    exit(1);
+    return REDIS_ERR; /* Just to avoid warning */
+}
+
+/* A background saving child (BGSAVE) terminated its work. Handle this. */
+void backgroundSaveDoneHandler(int statloc) {
+    int exitcode = WEXITSTATUS(statloc);
+    int bysignal = WIFSIGNALED(statloc);
+
+    if (!bysignal && exitcode == 0) {
+        redisLog(REDIS_NOTICE,
+            "Background saving terminated with success");
+        server.dirty = 0;
+        server.lastsave = time(NULL);
+    } else if (!bysignal && exitcode != 0) {
+        redisLog(REDIS_WARNING, "Background saving error");
+    } else {
+        redisLog(REDIS_WARNING,
+            "Background saving terminated by signal %d", WTERMSIG(statloc));
+        rdbRemoveTempFile(server.bgsavechildpid);
+    }
+    server.bgsavechildpid = -1;
+    /* Possibly there are slaves waiting for a BGSAVE in order to be served
+     * (the first stage of SYNC is a bulk transfer of dump.rdb) */
+    updateSlavesWaitingBgsave(exitcode == 0 ? REDIS_OK : REDIS_ERR);
+}

src/redis.h

@@ -0,0 +1,885 @@
+#ifndef __REDIS_H
+#define __REDIS_H
+
+#include "fmacros.h"
+#include "config.h"
+
+#if defined(__sun)
+#include "solarisfixes.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <limits.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "ae.h"     /* Event driven programming library */
+#include "sds.h"    /* Dynamic safe strings */
+#include "dict.h"   /* Hash tables */
+#include "adlist.h" /* Linked lists */
+#include "zmalloc.h" /* total memory usage aware version of malloc/free */
+#include "anet.h"   /* Networking the easy way */
+#include "zipmap.h" /* Compact string -> string data structure */
+#include "ziplist.h" /* Compact list data structure */
+#include "version.h"
+
+/* Error codes */
+#define REDIS_OK                0
+#define REDIS_ERR               -1
+
+/* Static server configuration */
+#define REDIS_SERVERPORT        6379    /* TCP port */
+#define REDIS_MAXIDLETIME       (60*5)  /* default client timeout */
+#define REDIS_IOBUF_LEN         1024
+#define REDIS_LOADBUF_LEN       1024
+#define REDIS_STATIC_ARGS       8
+#define REDIS_DEFAULT_DBNUM     16
+#define REDIS_CONFIGLINE_MAX    1024
+#define REDIS_OBJFREELIST_MAX   1000000 /* Max number of objects to cache */
+#define REDIS_MAX_SYNC_TIME     60      /* Slave can't take more to sync */
+#define REDIS_EXPIRELOOKUPS_PER_CRON    10 /* lookup 10 expires per loop */
+#define REDIS_MAX_WRITE_PER_EVENT (1024*64)
+#define REDIS_REQUEST_MAX_SIZE (1024*1024*256) /* max bytes in inline command */
+#define REDIS_SHARED_INTEGERS 10000
+
+/* If more then REDIS_WRITEV_THRESHOLD write packets are pending use writev */
+#define REDIS_WRITEV_THRESHOLD      3
+/* Max number of iovecs used for each writev call */
+#define REDIS_WRITEV_IOVEC_COUNT    256
+
+/* Hash table parameters */
+#define REDIS_HT_MINFILL        10      /* Minimal hash table fill 10% */
+
+/* Command flags */
+#define REDIS_CMD_BULK          1       /* Bulk write command */
+#define REDIS_CMD_INLINE        2       /* Inline command */
+/* REDIS_CMD_DENYOOM reserves a longer comment: all the commands marked with
+   this flags will return an error when the 'maxmemory' option is set in the
+   config file and the server is using more than maxmemory bytes of memory.
+   In short this commands are denied on low memory conditions. */
+#define REDIS_CMD_DENYOOM       4
+#define REDIS_CMD_FORCE_REPLICATION 8 /* Force replication even if dirty is 0 */
+
+/* Object types */
+#define REDIS_STRING 0
+#define REDIS_LIST 1
+#define REDIS_SET 2
+#define REDIS_ZSET 3
+#define REDIS_HASH 4
+#define REDIS_VMPOINTER 8
+
+/* Objects encoding. Some kind of objects like Strings and Hashes can be
+ * internally represented in multiple ways. The 'encoding' field of the object
+ * is set to one of this fields for this object. */
+#define REDIS_ENCODING_RAW 0     /* Raw representation */
+#define REDIS_ENCODING_INT 1     /* Encoded as integer */
+#define REDIS_ENCODING_HT 2      /* Encoded as hash table */
+#define REDIS_ENCODING_ZIPMAP 3  /* Encoded as zipmap */
+#define REDIS_ENCODING_LINKEDLIST 4 /* Encoded as regular linked list */
+#define REDIS_ENCODING_ZIPLIST 5 /* Encoded as ziplist */
+
+/* Object types only used for dumping to disk */
+#define REDIS_EXPIRETIME 253
+#define REDIS_SELECTDB 254
+#define REDIS_EOF 255
+
+/* Defines related to the dump file format. To store 32 bits lengths for short
+ * keys requires a lot of space, so we check the most significant 2 bits of
+ * the first byte to interpreter the length:
+ *
+ * 00|000000 => if the two MSB are 00 the len is the 6 bits of this byte
+ * 01|000000 00000000 =>  01, the len is 14 byes, 6 bits + 8 bits of next byte
+ * 10|000000 [32 bit integer] => if it's 01, a full 32 bit len will follow
+ * 11|000000 this means: specially encoded object will follow. The six bits
+ *           number specify the kind of object that follows.
+ *           See the REDIS_RDB_ENC_* defines.
+ *
+ * Lenghts up to 63 are stored using a single byte, most DB keys, and may
+ * values, will fit inside. */
+#define REDIS_RDB_6BITLEN 0
+#define REDIS_RDB_14BITLEN 1
+#define REDIS_RDB_32BITLEN 2
+#define REDIS_RDB_ENCVAL 3
+#define REDIS_RDB_LENERR UINT_MAX
+
+/* When a length of a string object stored on disk has the first two bits
+ * set, the remaining two bits specify a special encoding for the object
+ * accordingly to the following defines: */
+#define REDIS_RDB_ENC_INT8 0        /* 8 bit signed integer */
+#define REDIS_RDB_ENC_INT16 1       /* 16 bit signed integer */
+#define REDIS_RDB_ENC_INT32 2       /* 32 bit signed integer */
+#define REDIS_RDB_ENC_LZF 3         /* string compressed with FASTLZ */
+
+/* Virtual memory object->where field. */
+#define REDIS_VM_MEMORY 0       /* The object is on memory */
+#define REDIS_VM_SWAPPED 1      /* The object is on disk */
+#define REDIS_VM_SWAPPING 2     /* Redis is swapping this object on disk */
+#define REDIS_VM_LOADING 3      /* Redis is loading this object from disk */
+
+/* Virtual memory static configuration stuff.
+ * Check vmFindContiguousPages() to know more about this magic numbers. */
+#define REDIS_VM_MAX_NEAR_PAGES 65536
+#define REDIS_VM_MAX_RANDOM_JUMP 4096
+#define REDIS_VM_MAX_THREADS 32
+#define REDIS_THREAD_STACK_SIZE (1024*1024*4)
+/* The following is the *percentage* of completed I/O jobs to process when the
+ * handelr is called. While Virtual Memory I/O operations are performed by
+ * threads, this operations must be processed by the main thread when completed
+ * in order to take effect. */
+#define REDIS_MAX_COMPLETED_JOBS_PROCESSED 1
+
+/* Client flags */
+#define REDIS_SLAVE 1       /* This client is a slave server */
+#define REDIS_MASTER 2      /* This client is a master server */
+#define REDIS_MONITOR 4     /* This client is a slave monitor, see MONITOR */
+#define REDIS_MULTI 8       /* This client is in a MULTI context */
+#define REDIS_BLOCKED 16    /* The client is waiting in a blocking operation */
+#define REDIS_IO_WAIT 32    /* The client is waiting for Virtual Memory I/O */
+#define REDIS_DIRTY_CAS 64  /* Watched keys modified. EXEC will fail. */
+
+/* Slave replication state - slave side */
+#define REDIS_REPL_NONE 0   /* No active replication */
+#define REDIS_REPL_CONNECT 1    /* Must connect to master */
+#define REDIS_REPL_CONNECTED 2  /* Connected to master */
+
+/* Slave replication state - from the point of view of master
+ * Note that in SEND_BULK and ONLINE state the slave receives new updates
+ * in its output queue. In the WAIT_BGSAVE state instead the server is waiting
+ * to start the next background saving in order to send updates to it. */
+#define REDIS_REPL_WAIT_BGSAVE_START 3 /* master waits bgsave to start feeding it */
+#define REDIS_REPL_WAIT_BGSAVE_END 4 /* master waits bgsave to start bulk DB transmission */
+#define REDIS_REPL_SEND_BULK 5 /* master is sending the bulk DB */
+#define REDIS_REPL_ONLINE 6 /* bulk DB already transmitted, receive updates */
+
+/* List related stuff */
+#define REDIS_HEAD 0
+#define REDIS_TAIL 1
+
+/* Sort operations */
+#define REDIS_SORT_GET 0
+#define REDIS_SORT_ASC 1
+#define REDIS_SORT_DESC 2
+#define REDIS_SORTKEY_MAX 1024
+
+/* Log levels */
+#define REDIS_DEBUG 0
+#define REDIS_VERBOSE 1
+#define REDIS_NOTICE 2
+#define REDIS_WARNING 3
+
+/* Anti-warning macro... */
+#define REDIS_NOTUSED(V) ((void) V)
+
+#define ZSKIPLIST_MAXLEVEL 32 /* Should be enough for 2^32 elements */
+#define ZSKIPLIST_P 0.25      /* Skiplist P = 1/4 */
+
+/* Append only defines */
+#define APPENDFSYNC_NO 0
+#define APPENDFSYNC_ALWAYS 1
+#define APPENDFSYNC_EVERYSEC 2
+
+/* Zip structure related defaults */
+#define REDIS_HASH_MAX_ZIPMAP_ENTRIES 64
+#define REDIS_HASH_MAX_ZIPMAP_VALUE 512
+#define REDIS_LIST_MAX_ZIPLIST_ENTRIES 1024
+#define REDIS_LIST_MAX_ZIPLIST_VALUE 32
+
+/* Sets operations codes */
+#define REDIS_OP_UNION 0
+#define REDIS_OP_DIFF 1
+#define REDIS_OP_INTER 2
+
+/* We can print the stacktrace, so our assert is defined this way: */
+#define redisAssert(_e) ((_e)?(void)0 : (_redisAssert(#_e,__FILE__,__LINE__),_exit(1)))
+#define redisPanic(_e) _redisPanic(#_e,__FILE__,__LINE__),_exit(1)
+void _redisAssert(char *estr, char *file, int line);
+void _redisPanic(char *msg, char *file, int line);
+
+/*-----------------------------------------------------------------------------
+ * Data types
+ *----------------------------------------------------------------------------*/
+
+/* A redis object, that is a type able to hold a string / list / set */
+
+/* The actual Redis Object */
+typedef struct redisObject {
+    unsigned type:4;
+    unsigned storage:2;     /* REDIS_VM_MEMORY or REDIS_VM_SWAPPING */
+    unsigned encoding:4;
+    unsigned lru:22;        /* lru time (relative to server.lruclock) */
+    int refcount;
+    void *ptr;
+    /* VM fields are only allocated if VM is active, otherwise the
+     * object allocation function will just allocate
+     * sizeof(redisObjct) minus sizeof(redisObjectVM), so using
+     * Redis without VM active will not have any overhead. */
+} robj;
+
+/* The VM pointer structure - identifies an object in the swap file.
+ *
+ * This object is stored in place of the value
+ * object in the main key->value hash table representing a database.
+ * Note that the first fields (type, storage) are the same as the redisObject
+ * structure so that vmPointer strucuters can be accessed even when casted
+ * as redisObject structures.
+ *
+ * This is useful as we don't know if a value object is or not on disk, but we
+ * are always able to read obj->storage to check this. For vmPointer
+ * structures "type" is set to REDIS_VMPOINTER (even if without this field
+ * is still possible to check the kind of object from the value of 'storage').*/
+typedef struct vmPointer {
+    unsigned type:4;
+    unsigned storage:2; /* REDIS_VM_SWAPPED or REDIS_VM_LOADING */
+    unsigned notused:26;
+    unsigned int vtype; /* type of the object stored in the swap file */
+    off_t page;         /* the page at witch the object is stored on disk */
+    off_t usedpages;    /* number of pages used on disk */
+} vmpointer;
+
+/* Macro used to initalize a Redis object allocated on the stack.
+ * Note that this macro is taken near the structure definition to make sure
+ * we'll update it when the structure is changed, to avoid bugs like
+ * bug #85 introduced exactly in this way. */
+#define initStaticStringObject(_var,_ptr) do { \
+    _var.refcount = 1; \
+    _var.type = REDIS_STRING; \
+    _var.encoding = REDIS_ENCODING_RAW; \
+    _var.ptr = _ptr; \
+    _var.storage = REDIS_VM_MEMORY; \
+} while(0);
+
+typedef struct redisDb {
+    dict *dict;                 /* The keyspace for this DB */
+    dict *expires;              /* Timeout of keys with a timeout set */
+    dict *blocking_keys;        /* Keys with clients waiting for data (BLPOP) */
+    dict *io_keys;              /* Keys with clients waiting for VM I/O */
+    dict *watched_keys;         /* WATCHED keys for MULTI/EXEC CAS */
+    int id;
+} redisDb;
+
+/* Client MULTI/EXEC state */
+typedef struct multiCmd {
+    robj **argv;
+    int argc;
+    struct redisCommand *cmd;
+} multiCmd;
+
+typedef struct multiState {
+    multiCmd *commands;     /* Array of MULTI commands */
+    int count;              /* Total number of MULTI commands */
+} multiState;
+
+/* With multiplexing we need to take per-clinet state.
+ * Clients are taken in a liked list. */
+typedef struct redisClient {
+    int fd;
+    redisDb *db;
+    int dictid;
+    sds querybuf;
+    robj **argv, **mbargv;
+    int argc, mbargc;
+    int bulklen;            /* bulk read len. -1 if not in bulk read mode */
+    int multibulk;          /* multi bulk command format active */
+    list *reply;
+    int sentlen;
+    time_t lastinteraction; /* time of the last interaction, used for timeout */
+    int flags;              /* REDIS_SLAVE | REDIS_MONITOR | REDIS_MULTI ... */
+    int slaveseldb;         /* slave selected db, if this client is a slave */
+    int authenticated;      /* when requirepass is non-NULL */
+    int replstate;          /* replication state if this is a slave */
+    int repldbfd;           /* replication DB file descriptor */
+    long repldboff;         /* replication DB file offset */
+    off_t repldbsize;       /* replication DB file size */
+    multiState mstate;      /* MULTI/EXEC state */
+    robj **blocking_keys;   /* The key we are waiting to terminate a blocking
+                             * operation such as BLPOP. Otherwise NULL. */
+    int blocking_keys_num;  /* Number of blocking keys */
+    time_t blockingto;      /* Blocking operation timeout. If UNIX current time
+                             * is >= blockingto then the operation timed out. */
+    list *io_keys;          /* Keys this client is waiting to be loaded from the
+                             * swap file in order to continue. */
+    list *watched_keys;     /* Keys WATCHED for MULTI/EXEC CAS */
+    dict *pubsub_channels;  /* channels a client is interested in (SUBSCRIBE) */
+    list *pubsub_patterns;  /* patterns a client is interested in (SUBSCRIBE) */
+} redisClient;
+
+struct saveparam {
+    time_t seconds;
+    int changes;
+};
+
+struct sharedObjectsStruct {
+    robj *crlf, *ok, *err, *emptybulk, *czero, *cone, *cnegone, *pong, *space,
+    *colon, *nullbulk, *nullmultibulk, *queued,
+    *emptymultibulk, *wrongtypeerr, *nokeyerr, *syntaxerr, *sameobjecterr,
+    *outofrangeerr, *plus,
+    *select0, *select1, *select2, *select3, *select4,
+    *select5, *select6, *select7, *select8, *select9,
+    *messagebulk, *pmessagebulk, *subscribebulk, *unsubscribebulk, *mbulk3,
+    *mbulk4, *psubscribebulk, *punsubscribebulk,
+    *integers[REDIS_SHARED_INTEGERS];
+};
+
+/* Global server state structure */
+struct redisServer {
+    int port;
+    int fd;
+    redisDb *db;
+    long long dirty;            /* changes to DB from the last save */
+    list *clients;
+    list *slaves, *monitors;
+    char neterr[ANET_ERR_LEN];
+    aeEventLoop *el;
+    int cronloops;              /* number of times the cron function run */
+    list *objfreelist;          /* A list of freed objects to avoid malloc() */
+    time_t lastsave;            /* Unix time of last save succeeede */
+    /* Fields used only for stats */
+    time_t stat_starttime;         /* server start time */
+    long long stat_numcommands;    /* number of processed commands */
+    long long stat_numconnections; /* number of connections received */
+    long long stat_expiredkeys;   /* number of expired keys */
+    /* Configuration */
+    int verbosity;
+    int glueoutputbuf;
+    int maxidletime;
+    int dbnum;
+    int daemonize;
+    int appendonly;
+    int appendfsync;
+    int no_appendfsync_on_rewrite;
+    int shutdown_asap;
+    time_t lastfsync;
+    int appendfd;
+    int appendseldb;
+    char *pidfile;
+    pid_t bgsavechildpid;
+    pid_t bgrewritechildpid;
+    sds bgrewritebuf; /* buffer taken by parent during oppend only rewrite */
+    sds aofbuf;       /* AOF buffer, written before entering the event loop */
+    struct saveparam *saveparams;
+    int saveparamslen;
+    char *logfile;
+    char *bindaddr;
+    char *dbfilename;
+    char *appendfilename;
+    char *requirepass;
+    int rdbcompression;
+    int activerehashing;
+    /* Replication related */
+    int isslave;
+    char *masterauth;
+    char *masterhost;
+    int masterport;
+    redisClient *master;    /* client that is master for this slave */
+    int replstate;
+    unsigned int maxclients;
+    unsigned long long maxmemory;
+    unsigned int blpop_blocked_clients;
+    unsigned int vm_blocked_clients;
+    /* Sort parameters - qsort_r() is only available under BSD so we
+     * have to take this state global, in order to pass it to sortCompare() */
+    int sort_desc;
+    int sort_alpha;
+    int sort_bypattern;
+    /* Virtual memory configuration */
+    int vm_enabled;
+    char *vm_swap_file;
+    off_t vm_page_size;
+    off_t vm_pages;
+    unsigned long long vm_max_memory;
+    /* Zip structure config */
+    size_t hash_max_zipmap_entries;
+    size_t hash_max_zipmap_value;
+    size_t list_max_ziplist_entries;
+    size_t list_max_ziplist_value;
+    /* Virtual memory state */
+    FILE *vm_fp;
+    int vm_fd;
+    off_t vm_next_page; /* Next probably empty page */
+    off_t vm_near_pages; /* Number of pages allocated sequentially */
+    unsigned char *vm_bitmap; /* Bitmap of free/used pages */
+    time_t unixtime;    /* Unix time sampled every second. */
+    /* Virtual memory I/O threads stuff */
+    /* An I/O thread process an element taken from the io_jobs queue and
+     * put the result of the operation in the io_done list. While the
+     * job is being processed, it's put on io_processing queue. */
+    list *io_newjobs; /* List of VM I/O jobs yet to be processed */
+    list *io_processing; /* List of VM I/O jobs being processed */
+    list *io_processed; /* List of VM I/O jobs already processed */
+    list *io_ready_clients; /* Clients ready to be unblocked. All keys loaded */
+    pthread_mutex_t io_mutex; /* lock to access io_jobs/io_done/io_thread_job */
+    pthread_mutex_t obj_freelist_mutex; /* safe redis objects creation/free */
+    pthread_mutex_t io_swapfile_mutex; /* So we can lseek + write */
+    pthread_attr_t io_threads_attr; /* attributes for threads creation */
+    int io_active_threads; /* Number of running I/O threads */
+    int vm_max_threads; /* Max number of I/O threads running at the same time */
+    /* Our main thread is blocked on the event loop, locking for sockets ready
+     * to be read or written, so when a threaded I/O operation is ready to be
+     * processed by the main thread, the I/O thread will use a unix pipe to
+     * awake the main thread. The followings are the two pipe FDs. */
+    int io_ready_pipe_read;
+    int io_ready_pipe_write;
+    /* Virtual memory stats */
+    unsigned long long vm_stats_used_pages;
+    unsigned long long vm_stats_swapped_objects;
+    unsigned long long vm_stats_swapouts;
+    unsigned long long vm_stats_swapins;
+    /* Pubsub */
+    dict *pubsub_channels; /* Map channels to list of subscribed clients */
+    list *pubsub_patterns; /* A list of pubsub_patterns */
+    /* Misc */
+    FILE *devnull;
+    unsigned lruclock:22;        /* clock incrementing every minute, for LRU */
+    unsigned lruclock_padding:10;
+};
+
+typedef struct pubsubPattern {
+    redisClient *client;
+    robj *pattern;
+} pubsubPattern;
+
+typedef void redisCommandProc(redisClient *c);
+typedef void redisVmPreloadProc(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+struct redisCommand {
+    char *name;
+    redisCommandProc *proc;
+    int arity;
+    int flags;
+    /* Use a function to determine which keys need to be loaded
+     * in the background prior to executing this command. Takes precedence
+     * over vm_firstkey and others, ignored when NULL */
+    redisVmPreloadProc *vm_preload_proc;
+    /* What keys should be loaded in background when calling this command? */
+    int vm_firstkey; /* The first argument that's a key (0 = no keys) */
+    int vm_lastkey;  /* THe last argument that's a key */
+    int vm_keystep;  /* The step between first and last key */
+};
+
+struct redisFunctionSym {
+    char *name;
+    unsigned long pointer;
+};
+
+typedef struct _redisSortObject {
+    robj *obj;
+    union {
+        double score;
+        robj *cmpobj;
+    } u;
+} redisSortObject;
+
+typedef struct _redisSortOperation {
+    int type;
+    robj *pattern;
+} redisSortOperation;
+
+/* ZSETs use a specialized version of Skiplists */
+
+typedef struct zskiplistNode {
+    struct zskiplistNode **forward;
+    struct zskiplistNode *backward;
+    unsigned int *span;
+    double score;
+    robj *obj;
+} zskiplistNode;
+
+typedef struct zskiplist {
+    struct zskiplistNode *header, *tail;
+    unsigned long length;
+    int level;
+} zskiplist;
+
+typedef struct zset {
+    dict *dict;
+    zskiplist *zsl;
+} zset;
+
+/* VM threaded I/O request message */
+#define REDIS_IOJOB_LOAD 0          /* Load from disk to memory */
+#define REDIS_IOJOB_PREPARE_SWAP 1  /* Compute needed pages */
+#define REDIS_IOJOB_DO_SWAP 2       /* Swap from memory to disk */
+typedef struct iojob {
+    int type;   /* Request type, REDIS_IOJOB_* */
+    redisDb *db;/* Redis database */
+    robj *key;  /* This I/O request is about swapping this key */
+    robj *id;   /* Unique identifier of this job:
+                   this is the object to swap for REDIS_IOREQ_*_SWAP, or the
+                   vmpointer objct for REDIS_IOREQ_LOAD. */
+    robj *val;  /* the value to swap for REDIS_IOREQ_*_SWAP, otherwise this
+                 * field is populated by the I/O thread for REDIS_IOREQ_LOAD. */
+    off_t page; /* Swap page where to read/write the object */
+    off_t pages; /* Swap pages needed to save object. PREPARE_SWAP return val */
+    int canceled; /* True if this command was canceled by blocking side of VM */
+    pthread_t thread; /* ID of the thread processing this entry */
+} iojob;
+
+/* Structure to hold list iteration abstraction. */
+typedef struct {
+    robj *subject;
+    unsigned char encoding;
+    unsigned char direction; /* Iteration direction */
+    unsigned char *zi;
+    listNode *ln;
+} listTypeIterator;
+
+/* Structure for an entry while iterating over a list. */
+typedef struct {
+    listTypeIterator *li;
+    unsigned char *zi;  /* Entry in ziplist */
+    listNode *ln;       /* Entry in linked list */
+} listTypeEntry;
+
+/* Structure to hold hash iteration abstration. Note that iteration over
+ * hashes involves both fields and values. Because it is possible that
+ * not both are required, store pointers in the iterator to avoid
+ * unnecessary memory allocation for fields/values. */
+typedef struct {
+    int encoding;
+    unsigned char *zi;
+    unsigned char *zk, *zv;
+    unsigned int zklen, zvlen;
+
+    dictIterator *di;
+    dictEntry *de;
+} hashTypeIterator;
+
+#define REDIS_HASH_KEY 1
+#define REDIS_HASH_VALUE 2
+
+/*-----------------------------------------------------------------------------
+ * Extern declarations
+ *----------------------------------------------------------------------------*/
+
+extern struct redisServer server;
+extern struct sharedObjectsStruct shared;
+extern dictType setDictType;
+extern dictType zsetDictType;
+extern double R_Zero, R_PosInf, R_NegInf, R_Nan;
+dictType hashDictType;
+
+/*-----------------------------------------------------------------------------
+ * Functions prototypes
+ *----------------------------------------------------------------------------*/
+
+/* networking.c -- Networking and Client related operations */
+redisClient *createClient(int fd);
+void closeTimedoutClients(void);
+void freeClient(redisClient *c);
+void resetClient(redisClient *c);
+void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask);
+void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int mask);
+void addReply(redisClient *c, robj *obj);
+void addReplySds(redisClient *c, sds s);
+void processInputBuffer(redisClient *c);
+void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask);
+void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mask);
+void addReplyBulk(redisClient *c, robj *obj);
+void addReplyBulkCString(redisClient *c, char *s);
+void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask);
+void addReply(redisClient *c, robj *obj);
+void addReplySds(redisClient *c, sds s);
+void addReplyDouble(redisClient *c, double d);
+void addReplyLongLong(redisClient *c, long long ll);
+void addReplyUlong(redisClient *c, unsigned long ul);
+void *dupClientReplyValue(void *o);
+
+/* List data type */
+void listTypeTryConversion(robj *subject, robj *value);
+void listTypePush(robj *subject, robj *value, int where);
+robj *listTypePop(robj *subject, int where);
+unsigned long listTypeLength(robj *subject);
+listTypeIterator *listTypeInitIterator(robj *subject, int index, unsigned char direction);
+void listTypeReleaseIterator(listTypeIterator *li);
+int listTypeNext(listTypeIterator *li, listTypeEntry *entry);
+robj *listTypeGet(listTypeEntry *entry);
+void listTypeInsert(listTypeEntry *entry, robj *value, int where);
+int listTypeEqual(listTypeEntry *entry, robj *o);
+void listTypeDelete(listTypeEntry *entry);
+void listTypeConvert(robj *subject, int enc);
+void unblockClientWaitingData(redisClient *c);
+int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele);
+void popGenericCommand(redisClient *c, int where);
+
+/* MULTI/EXEC/WATCH... */
+void unwatchAllKeys(redisClient *c);
+void initClientMultiState(redisClient *c);
+void freeClientMultiState(redisClient *c);
+void queueMultiCommand(redisClient *c, struct redisCommand *cmd);
+void touchWatchedKey(redisDb *db, robj *key);
+void touchWatchedKeysOnFlush(int dbid);
+
+/* Redis object implementation */
+void decrRefCount(void *o);
+void incrRefCount(robj *o);
+void freeStringObject(robj *o);
+void freeListObject(robj *o);
+void freeSetObject(robj *o);
+void freeZsetObject(robj *o);
+void freeHashObject(robj *o);
+robj *createObject(int type, void *ptr);
+robj *createStringObject(char *ptr, size_t len);
+robj *dupStringObject(robj *o);
+robj *tryObjectEncoding(robj *o);
+robj *getDecodedObject(robj *o);
+size_t stringObjectLen(robj *o);
+int tryFreeOneObjectFromFreelist(void);
+robj *createStringObjectFromLongLong(long long value);
+robj *createListObject(void);
+robj *createZiplistObject(void);
+robj *createSetObject(void);
+robj *createHashObject(void);
+robj *createZsetObject(void);
+int getLongFromObjectOrReply(redisClient *c, robj *o, long *target, const char *msg);
+int checkType(redisClient *c, robj *o, int type);
+int getLongLongFromObjectOrReply(redisClient *c, robj *o, long long *target, const char *msg);
+int getDoubleFromObjectOrReply(redisClient *c, robj *o, double *target, const char *msg);
+int getLongLongFromObject(robj *o, long long *target);
+char *strEncoding(int encoding);
+int compareStringObjects(robj *a, robj *b);
+int equalStringObjects(robj *a, robj *b);
+
+/* Replication */
+void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc);
+void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc);
+int syncWithMaster(void);
+void updateSlavesWaitingBgsave(int bgsaveerr);
+
+/* RDB persistence */
+int rdbLoad(char *filename);
+int rdbSaveBackground(char *filename);
+void rdbRemoveTempFile(pid_t childpid);
+int rdbSave(char *filename);
+int rdbSaveObject(FILE *fp, robj *o);
+off_t rdbSavedObjectPages(robj *o, FILE *fp);
+off_t rdbSavedObjectLen(robj *o, FILE *fp);
+robj *rdbLoadObject(int type, FILE *fp);
+void backgroundSaveDoneHandler(int statloc);
+
+/* AOF persistence */
+void flushAppendOnlyFile(void);
+void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc);
+void aofRemoveTempFile(pid_t childpid);
+int rewriteAppendOnlyFileBackground(void);
+int loadAppendOnlyFile(char *filename);
+void stopAppendOnly(void);
+int startAppendOnly(void);
+void backgroundRewriteDoneHandler(int statloc);
+
+/* Sorted sets data type */
+zskiplist *zslCreate(void);
+void zslFree(zskiplist *zsl);
+void zslInsert(zskiplist *zsl, double score, robj *obj);
+
+/* Core functions */
+void freeMemoryIfNeeded(void);
+int processCommand(redisClient *c);
+void setupSigSegvAction(void);
+struct redisCommand *lookupCommand(char *name);
+void call(redisClient *c, struct redisCommand *cmd);
+int prepareForShutdown();
+void redisLog(int level, const char *fmt, ...);
+void usage();
+void updateDictResizePolicy(void);
+int htNeedsResize(dict *dict);
+void oom(const char *msg);
+
+/* Virtual Memory */
+void vmInit(void);
+void vmMarkPagesFree(off_t page, off_t count);
+robj *vmLoadObject(robj *o);
+robj *vmPreviewObject(robj *o);
+int vmSwapOneObjectBlocking(void);
+int vmSwapOneObjectThreaded(void);
+int vmCanSwapOut(void);
+void vmThreadedIOCompletedJob(aeEventLoop *el, int fd, void *privdata, int mask);
+void vmCancelThreadedIOJob(robj *o);
+void lockThreadedIO(void);
+void unlockThreadedIO(void);
+int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db);
+void freeIOJob(iojob *j);
+void queueIOJob(iojob *j);
+int vmWriteObjectOnSwap(robj *o, off_t page);
+robj *vmReadObjectFromSwap(off_t page, int type);
+void waitEmptyIOJobsQueue(void);
+void vmReopenSwapFile(void);
+int vmFreePage(off_t page);
+void zunionInterBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+int blockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd);
+int dontWaitForSwappedKey(redisClient *c, robj *key);
+void handleClientsBlockedOnSwappedKey(redisDb *db, robj *key);
+vmpointer *vmSwapObjectBlocking(robj *val);
+
+/* Hash data type */
+void convertToRealHash(robj *o);
+void hashTypeTryConversion(robj *subject, robj **argv, int start, int end);
+void hashTypeTryObjectEncoding(robj *subject, robj **o1, robj **o2);
+robj *hashTypeGet(robj *o, robj *key);
+int hashTypeExists(robj *o, robj *key);
+int hashTypeSet(robj *o, robj *key, robj *value);
+int hashTypeDelete(robj *o, robj *key);
+unsigned long hashTypeLength(robj *o);
+hashTypeIterator *hashTypeInitIterator(robj *subject);
+void hashTypeReleaseIterator(hashTypeIterator *hi);
+int hashTypeNext(hashTypeIterator *hi);
+robj *hashTypeCurrent(hashTypeIterator *hi, int what);
+robj *hashTypeLookupWriteOrCreate(redisClient *c, robj *key);
+
+/* Pub / Sub */
+int pubsubUnsubscribeAllChannels(redisClient *c, int notify);
+int pubsubUnsubscribeAllPatterns(redisClient *c, int notify);
+void freePubsubPattern(void *p);
+int listMatchPubsubPattern(void *a, void *b);
+
+/* Utility functions */
+int stringmatchlen(const char *pattern, int patternLen,
+        const char *string, int stringLen, int nocase);
+int stringmatch(const char *pattern, const char *string, int nocase);
+long long memtoll(const char *p, int *err);
+int ll2string(char *s, size_t len, long long value);
+int isStringRepresentableAsLong(sds s, long *longval);
+
+/* Configuration */
+void loadServerConfig(char *filename);
+void appendServerSaveParams(time_t seconds, int changes);
+void resetServerSaveParams();
+
+/* db.c -- Keyspace access API */
+int removeExpire(redisDb *db, robj *key);
+int expireIfNeeded(redisDb *db, robj *key);
+int deleteIfVolatile(redisDb *db, robj *key);
+time_t getExpire(redisDb *db, robj *key);
+int setExpire(redisDb *db, robj *key, time_t when);
+robj *lookupKey(redisDb *db, robj *key);
+robj *lookupKeyRead(redisDb *db, robj *key);
+robj *lookupKeyWrite(redisDb *db, robj *key);
+robj *lookupKeyReadOrReply(redisClient *c, robj *key, robj *reply);
+robj *lookupKeyWriteOrReply(redisClient *c, robj *key, robj *reply);
+int dbAdd(redisDb *db, robj *key, robj *val);
+int dbReplace(redisDb *db, robj *key, robj *val);
+int dbExists(redisDb *db, robj *key);
+robj *dbRandomKey(redisDb *db);
+int dbDelete(redisDb *db, robj *key);
+long long emptyDb();
+int selectDb(redisClient *c, int id);
+
+/* Git SHA1 */
+char *redisGitSHA1(void);
+char *redisGitDirty(void);
+
+/* Commands prototypes */
+void authCommand(redisClient *c);
+void pingCommand(redisClient *c);
+void echoCommand(redisClient *c);
+void setCommand(redisClient *c);
+void setnxCommand(redisClient *c);
+void setexCommand(redisClient *c);
+void getCommand(redisClient *c);
+void delCommand(redisClient *c);
+void existsCommand(redisClient *c);
+void incrCommand(redisClient *c);
+void decrCommand(redisClient *c);
+void incrbyCommand(redisClient *c);
+void decrbyCommand(redisClient *c);
+void selectCommand(redisClient *c);
+void randomkeyCommand(redisClient *c);
+void keysCommand(redisClient *c);
+void dbsizeCommand(redisClient *c);
+void lastsaveCommand(redisClient *c);
+void saveCommand(redisClient *c);
+void bgsaveCommand(redisClient *c);
+void bgrewriteaofCommand(redisClient *c);
+void shutdownCommand(redisClient *c);
+void moveCommand(redisClient *c);
+void renameCommand(redisClient *c);
+void renamenxCommand(redisClient *c);
+void lpushCommand(redisClient *c);
+void rpushCommand(redisClient *c);
+void lpushxCommand(redisClient *c);
+void rpushxCommand(redisClient *c);
+void linsertCommand(redisClient *c);
+void lpopCommand(redisClient *c);
+void rpopCommand(redisClient *c);
+void llenCommand(redisClient *c);
+void lindexCommand(redisClient *c);
+void lrangeCommand(redisClient *c);
+void ltrimCommand(redisClient *c);
+void typeCommand(redisClient *c);
+void lsetCommand(redisClient *c);
+void saddCommand(redisClient *c);
+void sremCommand(redisClient *c);
+void smoveCommand(redisClient *c);
+void sismemberCommand(redisClient *c);
+void scardCommand(redisClient *c);
+void spopCommand(redisClient *c);
+void srandmemberCommand(redisClient *c);
+void sinterCommand(redisClient *c);
+void sinterstoreCommand(redisClient *c);
+void sunionCommand(redisClient *c);
+void sunionstoreCommand(redisClient *c);
+void sdiffCommand(redisClient *c);
+void sdiffstoreCommand(redisClient *c);
+void syncCommand(redisClient *c);
+void flushdbCommand(redisClient *c);
+void flushallCommand(redisClient *c);
+void sortCommand(redisClient *c);
+void lremCommand(redisClient *c);
+void rpoplpushcommand(redisClient *c);
+void infoCommand(redisClient *c);
+void mgetCommand(redisClient *c);
+void monitorCommand(redisClient *c);
+void expireCommand(redisClient *c);
+void expireatCommand(redisClient *c);
+void getsetCommand(redisClient *c);
+void ttlCommand(redisClient *c);
+void slaveofCommand(redisClient *c);
+void debugCommand(redisClient *c);
+void msetCommand(redisClient *c);
+void msetnxCommand(redisClient *c);
+void zaddCommand(redisClient *c);
+void zincrbyCommand(redisClient *c);
+void zrangeCommand(redisClient *c);
+void zrangebyscoreCommand(redisClient *c);
+void zcountCommand(redisClient *c);
+void zrevrangeCommand(redisClient *c);
+void zcardCommand(redisClient *c);
+void zremCommand(redisClient *c);
+void zscoreCommand(redisClient *c);
+void zremrangebyscoreCommand(redisClient *c);
+void multiCommand(redisClient *c);
+void execCommand(redisClient *c);
+void discardCommand(redisClient *c);
+void blpopCommand(redisClient *c);
+void brpopCommand(redisClient *c);
+void appendCommand(redisClient *c);
+void substrCommand(redisClient *c);
+void zrankCommand(redisClient *c);
+void zrevrankCommand(redisClient *c);
+void hsetCommand(redisClient *c);
+void hsetnxCommand(redisClient *c);
+void hgetCommand(redisClient *c);
+void hmsetCommand(redisClient *c);
+void hmgetCommand(redisClient *c);
+void hdelCommand(redisClient *c);
+void hlenCommand(redisClient *c);
+void zremrangebyrankCommand(redisClient *c);
+void zunionstoreCommand(redisClient *c);
+void zinterstoreCommand(redisClient *c);
+void hkeysCommand(redisClient *c);
+void hvalsCommand(redisClient *c);
+void hgetallCommand(redisClient *c);
+void hexistsCommand(redisClient *c);
+void configCommand(redisClient *c);
+void hincrbyCommand(redisClient *c);
+void subscribeCommand(redisClient *c);
+void unsubscribeCommand(redisClient *c);
+void psubscribeCommand(redisClient *c);
+void punsubscribeCommand(redisClient *c);
+void publishCommand(redisClient *c);
+void watchCommand(redisClient *c);
+void unwatchCommand(redisClient *c);
+
+#endif

src/replication.c

@@ -0,0 +1,475 @@
+#include "redis.h"
+
+#include <sys/time.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
+    listNode *ln;
+    listIter li;
+    int outc = 0, j;
+    robj **outv;
+    /* We need 1+(ARGS*3) objects since commands are using the new protocol
+     * and we one 1 object for the first "*<count>\r\n" multibulk count, then
+     * for every additional object we have "$<count>\r\n" + object + "\r\n". */
+    robj *static_outv[REDIS_STATIC_ARGS*3+1];
+    robj *lenobj;
+
+    if (argc <= REDIS_STATIC_ARGS) {
+        outv = static_outv;
+    } else {
+        outv = zmalloc(sizeof(robj*)*(argc*3+1));
+    }
+
+    lenobj = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(), "*%d\r\n", argc));
+    lenobj->refcount = 0;
+    outv[outc++] = lenobj;
+    for (j = 0; j < argc; j++) {
+        lenobj = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(),"$%lu\r\n",
+                (unsigned long) stringObjectLen(argv[j])));
+        lenobj->refcount = 0;
+        outv[outc++] = lenobj;
+        outv[outc++] = argv[j];
+        outv[outc++] = shared.crlf;
+    }
+
+    /* Increment all the refcounts at start and decrement at end in order to
+     * be sure to free objects if there is no slave in a replication state
+     * able to be feed with commands */
+    for (j = 0; j < outc; j++) incrRefCount(outv[j]);
+    listRewind(slaves,&li);
+    while((ln = listNext(&li))) {
+        redisClient *slave = ln->value;
+
+        /* Don't feed slaves that are still waiting for BGSAVE to start */
+        if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) continue;
+
+        /* Feed all the other slaves, MONITORs and so on */
+        if (slave->slaveseldb != dictid) {
+            robj *selectcmd;
+
+            switch(dictid) {
+            case 0: selectcmd = shared.select0; break;
+            case 1: selectcmd = shared.select1; break;
+            case 2: selectcmd = shared.select2; break;
+            case 3: selectcmd = shared.select3; break;
+            case 4: selectcmd = shared.select4; break;
+            case 5: selectcmd = shared.select5; break;
+            case 6: selectcmd = shared.select6; break;
+            case 7: selectcmd = shared.select7; break;
+            case 8: selectcmd = shared.select8; break;
+            case 9: selectcmd = shared.select9; break;
+            default:
+                selectcmd = createObject(REDIS_STRING,
+                    sdscatprintf(sdsempty(),"select %d\r\n",dictid));
+                selectcmd->refcount = 0;
+                break;
+            }
+            addReply(slave,selectcmd);
+            slave->slaveseldb = dictid;
+        }
+        for (j = 0; j < outc; j++) addReply(slave,outv[j]);
+    }
+    for (j = 0; j < outc; j++) decrRefCount(outv[j]);
+    if (outv != static_outv) zfree(outv);
+}
+
+void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc) {
+    listNode *ln;
+    listIter li;
+    int j;
+    sds cmdrepr = sdsnew("+");
+    robj *cmdobj;
+    struct timeval tv;
+
+    gettimeofday(&tv,NULL);
+    cmdrepr = sdscatprintf(cmdrepr,"%ld.%ld ",(long)tv.tv_sec,(long)tv.tv_usec);
+    if (dictid != 0) cmdrepr = sdscatprintf(cmdrepr,"(db %d) ", dictid);
+
+    for (j = 0; j < argc; j++) {
+        if (argv[j]->encoding == REDIS_ENCODING_INT) {
+            cmdrepr = sdscatprintf(cmdrepr, "%ld", (long)argv[j]->ptr);
+        } else {
+            cmdrepr = sdscatrepr(cmdrepr,(char*)argv[j]->ptr,
+                        sdslen(argv[j]->ptr));
+        }
+        if (j != argc-1)
+            cmdrepr = sdscatlen(cmdrepr," ",1);
+    }
+    cmdrepr = sdscatlen(cmdrepr,"\r\n",2);
+    cmdobj = createObject(REDIS_STRING,cmdrepr);
+
+    listRewind(monitors,&li);
+    while((ln = listNext(&li))) {
+        redisClient *monitor = ln->value;
+        addReply(monitor,cmdobj);
+    }
+    decrRefCount(cmdobj);
+}
+
+int syncWrite(int fd, char *ptr, ssize_t size, int timeout) {
+    ssize_t nwritten, ret = size;
+    time_t start = time(NULL);
+
+    timeout++;
+    while(size) {
+        if (aeWait(fd,AE_WRITABLE,1000) & AE_WRITABLE) {
+            nwritten = write(fd,ptr,size);
+            if (nwritten == -1) return -1;
+            ptr += nwritten;
+            size -= nwritten;
+        }
+        if ((time(NULL)-start) > timeout) {
+            errno = ETIMEDOUT;
+            return -1;
+        }
+    }
+    return ret;
+}
+
+int syncRead(int fd, char *ptr, ssize_t size, int timeout) {
+    ssize_t nread, totread = 0;
+    time_t start = time(NULL);
+
+    timeout++;
+    while(size) {
+        if (aeWait(fd,AE_READABLE,1000) & AE_READABLE) {
+            nread = read(fd,ptr,size);
+            if (nread == -1) return -1;
+            ptr += nread;
+            size -= nread;
+            totread += nread;
+        }
+        if ((time(NULL)-start) > timeout) {
+            errno = ETIMEDOUT;
+            return -1;
+        }
+    }
+    return totread;
+}
+
+int syncReadLine(int fd, char *ptr, ssize_t size, int timeout) {
+    ssize_t nread = 0;
+
+    size--;
+    while(size) {
+        char c;
+
+        if (syncRead(fd,&c,1,timeout) == -1) return -1;
+        if (c == '\n') {
+            *ptr = '\0';
+            if (nread && *(ptr-1) == '\r') *(ptr-1) = '\0';
+            return nread;
+        } else {
+            *ptr++ = c;
+            *ptr = '\0';
+            nread++;
+        }
+    }
+    return nread;
+}
+
+void syncCommand(redisClient *c) {
+    /* ignore SYNC if aleady slave or in monitor mode */
+    if (c->flags & REDIS_SLAVE) return;
+
+    /* SYNC can't be issued when the server has pending data to send to
+     * the client about already issued commands. We need a fresh reply
+     * buffer registering the differences between the BGSAVE and the current
+     * dataset, so that we can copy to other slaves if needed. */
+    if (listLength(c->reply) != 0) {
+        addReplySds(c,sdsnew("-ERR SYNC is invalid with pending input\r\n"));
+        return;
+    }
+
+    redisLog(REDIS_NOTICE,"Slave ask for synchronization");
+    /* Here we need to check if there is a background saving operation
+     * in progress, or if it is required to start one */
+    if (server.bgsavechildpid != -1) {
+        /* Ok a background save is in progress. Let's check if it is a good
+         * one for replication, i.e. if there is another slave that is
+         * registering differences since the server forked to save */
+        redisClient *slave;
+        listNode *ln;
+        listIter li;
+
+        listRewind(server.slaves,&li);
+        while((ln = listNext(&li))) {
+            slave = ln->value;
+            if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) break;
+        }
+        if (ln) {
+            /* Perfect, the server is already registering differences for
+             * another slave. Set the right state, and copy the buffer. */
+            listRelease(c->reply);
+            c->reply = listDup(slave->reply);
+            c->replstate = REDIS_REPL_WAIT_BGSAVE_END;
+            redisLog(REDIS_NOTICE,"Waiting for end of BGSAVE for SYNC");
+        } else {
+            /* No way, we need to wait for the next BGSAVE in order to
+             * register differences */
+            c->replstate = REDIS_REPL_WAIT_BGSAVE_START;
+            redisLog(REDIS_NOTICE,"Waiting for next BGSAVE for SYNC");
+        }
+    } else {
+        /* Ok we don't have a BGSAVE in progress, let's start one */
+        redisLog(REDIS_NOTICE,"Starting BGSAVE for SYNC");
+        if (rdbSaveBackground(server.dbfilename) != REDIS_OK) {
+            redisLog(REDIS_NOTICE,"Replication failed, can't BGSAVE");
+            addReplySds(c,sdsnew("-ERR Unalbe to perform background save\r\n"));
+            return;
+        }
+        c->replstate = REDIS_REPL_WAIT_BGSAVE_END;
+    }
+    c->repldbfd = -1;
+    c->flags |= REDIS_SLAVE;
+    c->slaveseldb = 0;
+    listAddNodeTail(server.slaves,c);
+    return;
+}
+
+void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) {
+    redisClient *slave = privdata;
+    REDIS_NOTUSED(el);
+    REDIS_NOTUSED(mask);
+    char buf[REDIS_IOBUF_LEN];
+    ssize_t nwritten, buflen;
+
+    if (slave->repldboff == 0) {
+        /* Write the bulk write count before to transfer the DB. In theory here
+         * we don't know how much room there is in the output buffer of the
+         * socket, but in pratice SO_SNDLOWAT (the minimum count for output
+         * operations) will never be smaller than the few bytes we need. */
+        sds bulkcount;
+
+        bulkcount = sdscatprintf(sdsempty(),"$%lld\r\n",(unsigned long long)
+            slave->repldbsize);
+        if (write(fd,bulkcount,sdslen(bulkcount)) != (signed)sdslen(bulkcount))
+        {
+            sdsfree(bulkcount);
+            freeClient(slave);
+            return;
+        }
+        sdsfree(bulkcount);
+    }
+    lseek(slave->repldbfd,slave->repldboff,SEEK_SET);
+    buflen = read(slave->repldbfd,buf,REDIS_IOBUF_LEN);
+    if (buflen <= 0) {
+        redisLog(REDIS_WARNING,"Read error sending DB to slave: %s",
+            (buflen == 0) ? "premature EOF" : strerror(errno));
+        freeClient(slave);
+        return;
+    }
+    if ((nwritten = write(fd,buf,buflen)) == -1) {
+        redisLog(REDIS_VERBOSE,"Write error sending DB to slave: %s",
+            strerror(errno));
+        freeClient(slave);
+        return;
+    }
+    slave->repldboff += nwritten;
+    if (slave->repldboff == slave->repldbsize) {
+        close(slave->repldbfd);
+        slave->repldbfd = -1;
+        aeDeleteFileEvent(server.el,slave->fd,AE_WRITABLE);
+        slave->replstate = REDIS_REPL_ONLINE;
+        if (aeCreateFileEvent(server.el, slave->fd, AE_WRITABLE,
+            sendReplyToClient, slave) == AE_ERR) {
+            freeClient(slave);
+            return;
+        }
+        addReplySds(slave,sdsempty());
+        redisLog(REDIS_NOTICE,"Synchronization with slave succeeded");
+    }
+}
+
+/* This function is called at the end of every backgrond saving.
+ * The argument bgsaveerr is REDIS_OK if the background saving succeeded
+ * otherwise REDIS_ERR is passed to the function.
+ *
+ * The goal of this function is to handle slaves waiting for a successful
+ * background saving in order to perform non-blocking synchronization. */
+void updateSlavesWaitingBgsave(int bgsaveerr) {
+    listNode *ln;
+    int startbgsave = 0;
+    listIter li;
+
+    listRewind(server.slaves,&li);
+    while((ln = listNext(&li))) {
+        redisClient *slave = ln->value;
+
+        if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) {
+            startbgsave = 1;
+            slave->replstate = REDIS_REPL_WAIT_BGSAVE_END;
+        } else if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) {
+            struct redis_stat buf;
+
+            if (bgsaveerr != REDIS_OK) {
+                freeClient(slave);
+                redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error");
+                continue;
+            }
+            if ((slave->repldbfd = open(server.dbfilename,O_RDONLY)) == -1 ||
+                redis_fstat(slave->repldbfd,&buf) == -1) {
+                freeClient(slave);
+                redisLog(REDIS_WARNING,"SYNC failed. Can't open/stat DB after BGSAVE: %s", strerror(errno));
+                continue;
+            }
+            slave->repldboff = 0;
+            slave->repldbsize = buf.st_size;
+            slave->replstate = REDIS_REPL_SEND_BULK;
+            aeDeleteFileEvent(server.el,slave->fd,AE_WRITABLE);
+            if (aeCreateFileEvent(server.el, slave->fd, AE_WRITABLE, sendBulkToSlave, slave) == AE_ERR) {
+                freeClient(slave);
+                continue;
+            }
+        }
+    }
+    if (startbgsave) {
+        if (rdbSaveBackground(server.dbfilename) != REDIS_OK) {
+            listIter li;
+
+            listRewind(server.slaves,&li);
+            redisLog(REDIS_WARNING,"SYNC failed. BGSAVE failed");
+            while((ln = listNext(&li))) {
+                redisClient *slave = ln->value;
+
+                if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START)
+                    freeClient(slave);
+            }
+        }
+    }
+}
+
+int syncWithMaster(void) {
+    char buf[1024], tmpfile[256], authcmd[1024];
+    long dumpsize;
+    int fd = anetTcpConnect(NULL,server.masterhost,server.masterport);
+    int dfd, maxtries = 5;
+
+    if (fd == -1) {
+        redisLog(REDIS_WARNING,"Unable to connect to MASTER: %s",
+            strerror(errno));
+        return REDIS_ERR;
+    }
+
+    /* AUTH with the master if required. */
+    if(server.masterauth) {
+    	snprintf(authcmd, 1024, "AUTH %s\r\n", server.masterauth);
+    	if (syncWrite(fd, authcmd, strlen(server.masterauth)+7, 5) == -1) {
+            close(fd);
+            redisLog(REDIS_WARNING,"Unable to AUTH to MASTER: %s",
+                strerror(errno));
+            return REDIS_ERR;
+    	}
+        /* Read the AUTH result.  */
+        if (syncReadLine(fd,buf,1024,3600) == -1) {
+            close(fd);
+            redisLog(REDIS_WARNING,"I/O error reading auth result from MASTER: %s",
+                strerror(errno));
+            return REDIS_ERR;
+        }
+        if (buf[0] != '+') {
+            close(fd);
+            redisLog(REDIS_WARNING,"Cannot AUTH to MASTER, is the masterauth password correct?");
+            return REDIS_ERR;
+        }
+    }
+
+    /* Issue the SYNC command */
+    if (syncWrite(fd,"SYNC \r\n",7,5) == -1) {
+        close(fd);
+        redisLog(REDIS_WARNING,"I/O error writing to MASTER: %s",
+            strerror(errno));
+        return REDIS_ERR;
+    }
+    /* Read the bulk write count */
+    if (syncReadLine(fd,buf,1024,3600) == -1) {
+        close(fd);
+        redisLog(REDIS_WARNING,"I/O error reading bulk count from MASTER: %s",
+            strerror(errno));
+        return REDIS_ERR;
+    }
+    if (buf[0] != '$') {
+        close(fd);
+        redisLog(REDIS_WARNING,"Bad protocol from MASTER, the first byte is not '$', are you sure the host and port are right?");
+        return REDIS_ERR;
+    }
+    dumpsize = strtol(buf+1,NULL,10);
+    redisLog(REDIS_NOTICE,"Receiving %ld bytes data dump from MASTER",dumpsize);
+    /* Read the bulk write data on a temp file */
+    while(maxtries--) {
+        snprintf(tmpfile,256,
+            "temp-%d.%ld.rdb",(int)time(NULL),(long int)getpid());
+        dfd = open(tmpfile,O_CREAT|O_WRONLY|O_EXCL,0644);
+        if (dfd != -1) break;
+        sleep(1);
+    }
+    if (dfd == -1) {
+        close(fd);
+        redisLog(REDIS_WARNING,"Opening the temp file needed for MASTER <-> SLAVE synchronization: %s",strerror(errno));
+        return REDIS_ERR;
+    }
+    while(dumpsize) {
+        int nread, nwritten;
+
+        nread = read(fd,buf,(dumpsize < 1024)?dumpsize:1024);
+        if (nread == -1) {
+            redisLog(REDIS_WARNING,"I/O error trying to sync with MASTER: %s",
+                strerror(errno));
+            close(fd);
+            close(dfd);
+            return REDIS_ERR;
+        }
+        nwritten = write(dfd,buf,nread);
+        if (nwritten == -1) {
+            redisLog(REDIS_WARNING,"Write error writing to the DB dump file needed for MASTER <-> SLAVE synchrnonization: %s", strerror(errno));
+            close(fd);
+            close(dfd);
+            return REDIS_ERR;
+        }
+        dumpsize -= nread;
+    }
+    close(dfd);
+    if (rename(tmpfile,server.dbfilename) == -1) {
+        redisLog(REDIS_WARNING,"Failed trying to rename the temp DB into dump.rdb in MASTER <-> SLAVE synchronization: %s", strerror(errno));
+        unlink(tmpfile);
+        close(fd);
+        return REDIS_ERR;
+    }
+    emptyDb();
+    if (rdbLoad(server.dbfilename) != REDIS_OK) {
+        redisLog(REDIS_WARNING,"Failed trying to load the MASTER synchronization DB from disk");
+        close(fd);
+        return REDIS_ERR;
+    }
+    server.master = createClient(fd);
+    server.master->flags |= REDIS_MASTER;
+    server.master->authenticated = 1;
+    server.replstate = REDIS_REPL_CONNECTED;
+    return REDIS_OK;
+}
+
+void slaveofCommand(redisClient *c) {
+    if (!strcasecmp(c->argv[1]->ptr,"no") &&
+        !strcasecmp(c->argv[2]->ptr,"one")) {
+        if (server.masterhost) {
+            sdsfree(server.masterhost);
+            server.masterhost = NULL;
+            if (server.master) freeClient(server.master);
+            server.replstate = REDIS_REPL_NONE;
+            redisLog(REDIS_NOTICE,"MASTER MODE enabled (user request)");
+        }
+    } else {
+        sdsfree(server.masterhost);
+        server.masterhost = sdsdup(c->argv[1]->ptr);
+        server.masterport = atoi(c->argv[2]->ptr);
+        if (server.master) freeClient(server.master);
+        server.replstate = REDIS_REPL_CONNECT;
+        redisLog(REDIS_NOTICE,"SLAVE OF %s:%d enabled (user request)",
+            server.masterhost, server.masterport);
+    }
+    addReply(c,shared.ok);
+}

src/sds.c

@@ -201,7 +201,7 @@ sds sdstrim(sds s, const char *cset) {
     return s;
 }
 
-sds sdsrange(sds s, long start, long end) {
+sds sdsrange(sds s, int start, int end) {
     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
     size_t newlen, len = sdslen(s);
 
@@ -357,3 +357,28 @@ sds sdsfromlonglong(long long value) {
     p++;
     return sdsnewlen(p,32-(p-buf));
 }
+
+sds sdscatrepr(sds s, char *p, size_t len) {
+    s = sdscatlen(s,"\"",1);
+    while(len--) {
+        switch(*p) {
+        case '\\':
+        case '"':
+            s = sdscatprintf(s,"\\%c",*p);
+            break;
+        case '\n': s = sdscatlen(s,"\\n",1); break;
+        case '\r': s = sdscatlen(s,"\\r",1); break;
+        case '\t': s = sdscatlen(s,"\\t",1); break;
+        case '\a': s = sdscatlen(s,"\\a",1); break;
+        case '\b': s = sdscatlen(s,"\\b",1); break;
+        default:
+            if (isprint(*p))
+                s = sdscatprintf(s,"%c",*p);
+            else
+                s = sdscatprintf(s,"\\x%02x",(unsigned char)*p);
+            break;
+        }
+        p++;
+    }
+    return sdscatlen(s,"\"",1);
+}

src/sds.h

@@ -36,8 +36,8 @@
 typedef char *sds;
 
 struct sdshdr {
-    long len;
-    long free;
+    int len;
+    int free;
     char buf[];
 };
 
@@ -61,7 +61,7 @@ sds sdscatprintf(sds s, const char *fmt, ...);
 #endif
 
 sds sdstrim(sds s, const char *cset);
-sds sdsrange(sds s, long start, long end);
+sds sdsrange(sds s, int start, int end);
 void sdsupdatelen(sds s);
 int sdscmp(sds s1, sds s2);
 sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count);
@@ -69,5 +69,6 @@ void sdsfreesplitres(sds *tokens, int count);
 void sdstolower(sds s);
 void sdstoupper(sds s);
 sds sdsfromlonglong(long long value);
+sds sdscatrepr(sds s, char *p, size_t len);
 
 #endif

src/sort.c

@@ -0,0 +1,383 @@
+#include "redis.h"
+#include "pqsort.h" /* Partial qsort for SORT+LIMIT */
+
+redisSortOperation *createSortOperation(int type, robj *pattern) {
+    redisSortOperation *so = zmalloc(sizeof(*so));
+    so->type = type;
+    so->pattern = pattern;
+    return so;
+}
+
+/* Return the value associated to the key with a name obtained
+ * substituting the first occurence of '*' in 'pattern' with 'subst'.
+ * The returned object will always have its refcount increased by 1
+ * when it is non-NULL. */
+robj *lookupKeyByPattern(redisDb *db, robj *pattern, robj *subst) {
+    char *p, *f;
+    sds spat, ssub;
+    robj keyobj, fieldobj, *o;
+    int prefixlen, sublen, postfixlen, fieldlen;
+    /* Expoit the internal sds representation to create a sds string allocated on the stack in order to make this function faster */
+    struct {
+        int len;
+        int free;
+        char buf[REDIS_SORTKEY_MAX+1];
+    } keyname, fieldname;
+
+    /* If the pattern is "#" return the substitution object itself in order
+     * to implement the "SORT ... GET #" feature. */
+    spat = pattern->ptr;
+    if (spat[0] == '#' && spat[1] == '\0') {
+        incrRefCount(subst);
+        return subst;
+    }
+
+    /* The substitution object may be specially encoded. If so we create
+     * a decoded object on the fly. Otherwise getDecodedObject will just
+     * increment the ref count, that we'll decrement later. */
+    subst = getDecodedObject(subst);
+
+    ssub = subst->ptr;
+    if (sdslen(spat)+sdslen(ssub)-1 > REDIS_SORTKEY_MAX) return NULL;
+    p = strchr(spat,'*');
+    if (!p) {
+        decrRefCount(subst);
+        return NULL;
+    }
+
+    /* Find out if we're dealing with a hash dereference. */
+    if ((f = strstr(p+1, "->")) != NULL) {
+        fieldlen = sdslen(spat)-(f-spat);
+        /* this also copies \0 character */
+        memcpy(fieldname.buf,f+2,fieldlen-1);
+        fieldname.len = fieldlen-2;
+    } else {
+        fieldlen = 0;
+    }
+
+    prefixlen = p-spat;
+    sublen = sdslen(ssub);
+    postfixlen = sdslen(spat)-(prefixlen+1)-fieldlen;
+    memcpy(keyname.buf,spat,prefixlen);
+    memcpy(keyname.buf+prefixlen,ssub,sublen);
+    memcpy(keyname.buf+prefixlen+sublen,p+1,postfixlen);
+    keyname.buf[prefixlen+sublen+postfixlen] = '\0';
+    keyname.len = prefixlen+sublen+postfixlen;
+    decrRefCount(subst);
+
+    /* Lookup substituted key */
+    initStaticStringObject(keyobj,((char*)&keyname)+(sizeof(struct sdshdr)));
+    o = lookupKeyRead(db,&keyobj);
+    if (o == NULL) return NULL;
+
+    if (fieldlen > 0) {
+        if (o->type != REDIS_HASH || fieldname.len < 1) return NULL;
+
+        /* Retrieve value from hash by the field name. This operation
+         * already increases the refcount of the returned object. */
+        initStaticStringObject(fieldobj,((char*)&fieldname)+(sizeof(struct sdshdr)));
+        o = hashTypeGet(o, &fieldobj);
+    } else {
+        if (o->type != REDIS_STRING) return NULL;
+
+        /* Every object that this function returns needs to have its refcount
+         * increased. sortCommand decreases it again. */
+        incrRefCount(o);
+    }
+
+    return o;
+}
+
+/* sortCompare() is used by qsort in sortCommand(). Given that qsort_r with
+ * the additional parameter is not standard but a BSD-specific we have to
+ * pass sorting parameters via the global 'server' structure */
+int sortCompare(const void *s1, const void *s2) {
+    const redisSortObject *so1 = s1, *so2 = s2;
+    int cmp;
+
+    if (!server.sort_alpha) {
+        /* Numeric sorting. Here it's trivial as we precomputed scores */
+        if (so1->u.score > so2->u.score) {
+            cmp = 1;
+        } else if (so1->u.score < so2->u.score) {
+            cmp = -1;
+        } else {
+            cmp = 0;
+        }
+    } else {
+        /* Alphanumeric sorting */
+        if (server.sort_bypattern) {
+            if (!so1->u.cmpobj || !so2->u.cmpobj) {
+                /* At least one compare object is NULL */
+                if (so1->u.cmpobj == so2->u.cmpobj)
+                    cmp = 0;
+                else if (so1->u.cmpobj == NULL)
+                    cmp = -1;
+                else
+                    cmp = 1;
+            } else {
+                /* We have both the objects, use strcoll */
+                cmp = strcoll(so1->u.cmpobj->ptr,so2->u.cmpobj->ptr);
+            }
+        } else {
+            /* Compare elements directly. */
+            cmp = compareStringObjects(so1->obj,so2->obj);
+        }
+    }
+    return server.sort_desc ? -cmp : cmp;
+}
+
+/* The SORT command is the most complex command in Redis. Warning: this code
+ * is optimized for speed and a bit less for readability */
+void sortCommand(redisClient *c) {
+    list *operations;
+    unsigned int outputlen = 0;
+    int desc = 0, alpha = 0;
+    int limit_start = 0, limit_count = -1, start, end;
+    int j, dontsort = 0, vectorlen;
+    int getop = 0; /* GET operation counter */
+    robj *sortval, *sortby = NULL, *storekey = NULL;
+    redisSortObject *vector; /* Resulting vector to sort */
+
+    /* Lookup the key to sort. It must be of the right types */
+    sortval = lookupKeyRead(c->db,c->argv[1]);
+    if (sortval == NULL) {
+        addReply(c,shared.emptymultibulk);
+        return;
+    }
+    if (sortval->type != REDIS_SET && sortval->type != REDIS_LIST &&
+        sortval->type != REDIS_ZSET)
+    {
+        addReply(c,shared.wrongtypeerr);
+        return;
+    }
+
+    /* Create a list of operations to perform for every sorted element.
+     * Operations can be GET/DEL/INCR/DECR */
+    operations = listCreate();
+    listSetFreeMethod(operations,zfree);
+    j = 2;
+
+    /* Now we need to protect sortval incrementing its count, in the future
+     * SORT may have options able to overwrite/delete keys during the sorting
+     * and the sorted key itself may get destroied */
+    incrRefCount(sortval);
+
+    /* The SORT command has an SQL-alike syntax, parse it */
+    while(j < c->argc) {
+        int leftargs = c->argc-j-1;
+        if (!strcasecmp(c->argv[j]->ptr,"asc")) {
+            desc = 0;
+        } else if (!strcasecmp(c->argv[j]->ptr,"desc")) {
+            desc = 1;
+        } else if (!strcasecmp(c->argv[j]->ptr,"alpha")) {
+            alpha = 1;
+        } else if (!strcasecmp(c->argv[j]->ptr,"limit") && leftargs >= 2) {
+            limit_start = atoi(c->argv[j+1]->ptr);
+            limit_count = atoi(c->argv[j+2]->ptr);
+            j+=2;
+        } else if (!strcasecmp(c->argv[j]->ptr,"store") && leftargs >= 1) {
+            storekey = c->argv[j+1];
+            j++;
+        } else if (!strcasecmp(c->argv[j]->ptr,"by") && leftargs >= 1) {
+            sortby = c->argv[j+1];
+            /* If the BY pattern does not contain '*', i.e. it is constant,
+             * we don't need to sort nor to lookup the weight keys. */
+            if (strchr(c->argv[j+1]->ptr,'*') == NULL) dontsort = 1;
+            j++;
+        } else if (!strcasecmp(c->argv[j]->ptr,"get") && leftargs >= 1) {
+            listAddNodeTail(operations,createSortOperation(
+                REDIS_SORT_GET,c->argv[j+1]));
+            getop++;
+            j++;
+        } else {
+            decrRefCount(sortval);
+            listRelease(operations);
+            addReply(c,shared.syntaxerr);
+            return;
+        }
+        j++;
+    }
+
+    /* Load the sorting vector with all the objects to sort */
+    switch(sortval->type) {
+    case REDIS_LIST: vectorlen = listTypeLength(sortval); break;
+    case REDIS_SET: vectorlen =  dictSize((dict*)sortval->ptr); break;
+    case REDIS_ZSET: vectorlen = dictSize(((zset*)sortval->ptr)->dict); break;
+    default: vectorlen = 0; redisPanic("Bad SORT type"); /* Avoid GCC warning */
+    }
+    vector = zmalloc(sizeof(redisSortObject)*vectorlen);
+    j = 0;
+
+    if (sortval->type == REDIS_LIST) {
+        listTypeIterator *li = listTypeInitIterator(sortval,0,REDIS_TAIL);
+        listTypeEntry entry;
+        while(listTypeNext(li,&entry)) {
+            vector[j].obj = listTypeGet(&entry);
+            vector[j].u.score = 0;
+            vector[j].u.cmpobj = NULL;
+            j++;
+        }
+        listTypeReleaseIterator(li);
+    } else {
+        dict *set;
+        dictIterator *di;
+        dictEntry *setele;
+
+        if (sortval->type == REDIS_SET) {
+            set = sortval->ptr;
+        } else {
+            zset *zs = sortval->ptr;
+            set = zs->dict;
+        }
+
+        di = dictGetIterator(set);
+        while((setele = dictNext(di)) != NULL) {
+            vector[j].obj = dictGetEntryKey(setele);
+            vector[j].u.score = 0;
+            vector[j].u.cmpobj = NULL;
+            j++;
+        }
+        dictReleaseIterator(di);
+    }
+    redisAssert(j == vectorlen);
+
+    /* Now it's time to load the right scores in the sorting vector */
+    if (dontsort == 0) {
+        for (j = 0; j < vectorlen; j++) {
+            robj *byval;
+            if (sortby) {
+                /* lookup value to sort by */
+                byval = lookupKeyByPattern(c->db,sortby,vector[j].obj);
+                if (!byval) continue;
+            } else {
+                /* use object itself to sort by */
+                byval = vector[j].obj;
+            }
+
+            if (alpha) {
+                if (sortby) vector[j].u.cmpobj = getDecodedObject(byval);
+            } else {
+                if (byval->encoding == REDIS_ENCODING_RAW) {
+                    vector[j].u.score = strtod(byval->ptr,NULL);
+                } else if (byval->encoding == REDIS_ENCODING_INT) {
+                    /* Don't need to decode the object if it's
+                     * integer-encoded (the only encoding supported) so
+                     * far. We can just cast it */
+                    vector[j].u.score = (long)byval->ptr;
+                } else {
+                    redisAssert(1 != 1);
+                }
+            }
+
+            /* when the object was retrieved using lookupKeyByPattern,
+             * its refcount needs to be decreased. */
+            if (sortby) {
+                decrRefCount(byval);
+            }
+        }
+    }
+
+    /* We are ready to sort the vector... perform a bit of sanity check
+     * on the LIMIT option too. We'll use a partial version of quicksort. */
+    start = (limit_start < 0) ? 0 : limit_start;
+    end = (limit_count < 0) ? vectorlen-1 : start+limit_count-1;
+    if (start >= vectorlen) {
+        start = vectorlen-1;
+        end = vectorlen-2;
+    }
+    if (end >= vectorlen) end = vectorlen-1;
+
+    if (dontsort == 0) {
+        server.sort_desc = desc;
+        server.sort_alpha = alpha;
+        server.sort_bypattern = sortby ? 1 : 0;
+        if (sortby && (start != 0 || end != vectorlen-1))
+            pqsort(vector,vectorlen,sizeof(redisSortObject),sortCompare, start,end);
+        else
+            qsort(vector,vectorlen,sizeof(redisSortObject),sortCompare);
+    }
+
+    /* Send command output to the output buffer, performing the specified
+     * GET/DEL/INCR/DECR operations if any. */
+    outputlen = getop ? getop*(end-start+1) : end-start+1;
+    if (storekey == NULL) {
+        /* STORE option not specified, sent the sorting result to client */
+        addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",outputlen));
+        for (j = start; j <= end; j++) {
+            listNode *ln;
+            listIter li;
+
+            if (!getop) addReplyBulk(c,vector[j].obj);
+            listRewind(operations,&li);
+            while((ln = listNext(&li))) {
+                redisSortOperation *sop = ln->value;
+                robj *val = lookupKeyByPattern(c->db,sop->pattern,
+                    vector[j].obj);
+
+                if (sop->type == REDIS_SORT_GET) {
+                    if (!val) {
+                        addReply(c,shared.nullbulk);
+                    } else {
+                        addReplyBulk(c,val);
+                        decrRefCount(val);
+                    }
+                } else {
+                    redisAssert(sop->type == REDIS_SORT_GET); /* always fails */
+                }
+            }
+        }
+    } else {
+        robj *sobj = createZiplistObject();
+
+        /* STORE option specified, set the sorting result as a List object */
+        for (j = start; j <= end; j++) {
+            listNode *ln;
+            listIter li;
+
+            if (!getop) {
+                listTypePush(sobj,vector[j].obj,REDIS_TAIL);
+            } else {
+                listRewind(operations,&li);
+                while((ln = listNext(&li))) {
+                    redisSortOperation *sop = ln->value;
+                    robj *val = lookupKeyByPattern(c->db,sop->pattern,
+                        vector[j].obj);
+
+                    if (sop->type == REDIS_SORT_GET) {
+                        if (!val) val = createStringObject("",0);
+
+                        /* listTypePush does an incrRefCount, so we should take care
+                         * care of the incremented refcount caused by either
+                         * lookupKeyByPattern or createStringObject("",0) */
+                        listTypePush(sobj,val,REDIS_TAIL);
+                        decrRefCount(val);
+                    } else {
+                        /* always fails */
+                        redisAssert(sop->type == REDIS_SORT_GET);
+                    }
+                }
+            }
+        }
+        dbReplace(c->db,storekey,sobj);
+        /* Note: we add 1 because the DB is dirty anyway since even if the
+         * SORT result is empty a new key is set and maybe the old content
+         * replaced. */
+        server.dirty += 1+outputlen;
+        addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",outputlen));
+    }
+
+    /* Cleanup */
+    if (sortval->type == REDIS_LIST)
+        for (j = 0; j < vectorlen; j++)
+            decrRefCount(vector[j].obj);
+    decrRefCount(sortval);
+    listRelease(operations);
+    for (j = 0; j < vectorlen; j++) {
+        if (alpha && vector[j].u.cmpobj)
+            decrRefCount(vector[j].u.cmpobj);
+    }
+    zfree(vector);
+}
+
+

src/t_hash.c

@@ -0,0 +1,397 @@
+#include "redis.h"
+
+#include <math.h>
+
+/*-----------------------------------------------------------------------------
+ * Hash type API
+ *----------------------------------------------------------------------------*/
+
+/* Check the length of a number of objects to see if we need to convert a
+ * zipmap to a real hash. Note that we only check string encoded objects
+ * as their string length can be queried in constant time. */
+void hashTypeTryConversion(robj *subject, robj **argv, int start, int end) {
+    int i;
+    if (subject->encoding != REDIS_ENCODING_ZIPMAP) return;
+
+    for (i = start; i <= end; i++) {
+        if (argv[i]->encoding == REDIS_ENCODING_RAW &&
+            sdslen(argv[i]->ptr) > server.hash_max_zipmap_value)
+        {
+            convertToRealHash(subject);
+            return;
+        }
+    }
+}
+
+/* Encode given objects in-place when the hash uses a dict. */
+void hashTypeTryObjectEncoding(robj *subject, robj **o1, robj **o2) {
+    if (subject->encoding == REDIS_ENCODING_HT) {
+        if (o1) *o1 = tryObjectEncoding(*o1);
+        if (o2) *o2 = tryObjectEncoding(*o2);
+    }
+}
+
+/* Get the value from a hash identified by key. Returns either a string
+ * object or NULL if the value cannot be found. The refcount of the object
+ * is always increased by 1 when the value was found. */
+robj *hashTypeGet(robj *o, robj *key) {
+    robj *value = NULL;
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        unsigned char *v;
+        unsigned int vlen;
+        key = getDecodedObject(key);
+        if (zipmapGet(o->ptr,key->ptr,sdslen(key->ptr),&v,&vlen)) {
+            value = createStringObject((char*)v,vlen);
+        }
+        decrRefCount(key);
+    } else {
+        dictEntry *de = dictFind(o->ptr,key);
+        if (de != NULL) {
+            value = dictGetEntryVal(de);
+            incrRefCount(value);
+        }
+    }
+    return value;
+}
+
+/* Test if the key exists in the given hash. Returns 1 if the key
+ * exists and 0 when it doesn't. */
+int hashTypeExists(robj *o, robj *key) {
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        key = getDecodedObject(key);
+        if (zipmapExists(o->ptr,key->ptr,sdslen(key->ptr))) {
+            decrRefCount(key);
+            return 1;
+        }
+        decrRefCount(key);
+    } else {
+        if (dictFind(o->ptr,key) != NULL) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+/* Add an element, discard the old if the key already exists.
+ * Return 0 on insert and 1 on update. */
+int hashTypeSet(robj *o, robj *key, robj *value) {
+    int update = 0;
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        key = getDecodedObject(key);
+        value = getDecodedObject(value);
+        o->ptr = zipmapSet(o->ptr,
+            key->ptr,sdslen(key->ptr),
+            value->ptr,sdslen(value->ptr), &update);
+        decrRefCount(key);
+        decrRefCount(value);
+
+        /* Check if the zipmap needs to be upgraded to a real hash table */
+        if (zipmapLen(o->ptr) > server.hash_max_zipmap_entries)
+            convertToRealHash(o);
+    } else {
+        if (dictReplace(o->ptr,key,value)) {
+            /* Insert */
+            incrRefCount(key);
+        } else {
+            /* Update */
+            update = 1;
+        }
+        incrRefCount(value);
+    }
+    return update;
+}
+
+/* Delete an element from a hash.
+ * Return 1 on deleted and 0 on not found. */
+int hashTypeDelete(robj *o, robj *key) {
+    int deleted = 0;
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        key = getDecodedObject(key);
+        o->ptr = zipmapDel(o->ptr,key->ptr,sdslen(key->ptr), &deleted);
+        decrRefCount(key);
+    } else {
+        deleted = dictDelete((dict*)o->ptr,key) == DICT_OK;
+        /* Always check if the dictionary needs a resize after a delete. */
+        if (deleted && htNeedsResize(o->ptr)) dictResize(o->ptr);
+    }
+    return deleted;
+}
+
+/* Return the number of elements in a hash. */
+unsigned long hashTypeLength(robj *o) {
+    return (o->encoding == REDIS_ENCODING_ZIPMAP) ?
+        zipmapLen((unsigned char*)o->ptr) : dictSize((dict*)o->ptr);
+}
+
+hashTypeIterator *hashTypeInitIterator(robj *subject) {
+    hashTypeIterator *hi = zmalloc(sizeof(hashTypeIterator));
+    hi->encoding = subject->encoding;
+    if (hi->encoding == REDIS_ENCODING_ZIPMAP) {
+        hi->zi = zipmapRewind(subject->ptr);
+    } else if (hi->encoding == REDIS_ENCODING_HT) {
+        hi->di = dictGetIterator(subject->ptr);
+    } else {
+        redisAssert(NULL);
+    }
+    return hi;
+}
+
+void hashTypeReleaseIterator(hashTypeIterator *hi) {
+    if (hi->encoding == REDIS_ENCODING_HT) {
+        dictReleaseIterator(hi->di);
+    }
+    zfree(hi);
+}
+
+/* Move to the next entry in the hash. Return REDIS_OK when the next entry
+ * could be found and REDIS_ERR when the iterator reaches the end. */
+int hashTypeNext(hashTypeIterator *hi) {
+    if (hi->encoding == REDIS_ENCODING_ZIPMAP) {
+        if ((hi->zi = zipmapNext(hi->zi, &hi->zk, &hi->zklen,
+            &hi->zv, &hi->zvlen)) == NULL) return REDIS_ERR;
+    } else {
+        if ((hi->de = dictNext(hi->di)) == NULL) return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
+/* Get key or value object at current iteration position.
+ * This increases the refcount of the field object by 1. */
+robj *hashTypeCurrent(hashTypeIterator *hi, int what) {
+    robj *o;
+    if (hi->encoding == REDIS_ENCODING_ZIPMAP) {
+        if (what & REDIS_HASH_KEY) {
+            o = createStringObject((char*)hi->zk,hi->zklen);
+        } else {
+            o = createStringObject((char*)hi->zv,hi->zvlen);
+        }
+    } else {
+        if (what & REDIS_HASH_KEY) {
+            o = dictGetEntryKey(hi->de);
+        } else {
+            o = dictGetEntryVal(hi->de);
+        }
+        incrRefCount(o);
+    }
+    return o;
+}
+
+robj *hashTypeLookupWriteOrCreate(redisClient *c, robj *key) {
+    robj *o = lookupKeyWrite(c->db,key);
+    if (o == NULL) {
+        o = createHashObject();
+        dbAdd(c->db,key,o);
+    } else {
+        if (o->type != REDIS_HASH) {
+            addReply(c,shared.wrongtypeerr);
+            return NULL;
+        }
+    }
+    return o;
+}
+
+void convertToRealHash(robj *o) {
+    unsigned char *key, *val, *p, *zm = o->ptr;
+    unsigned int klen, vlen;
+    dict *dict = dictCreate(&hashDictType,NULL);
+
+    redisAssert(o->type == REDIS_HASH && o->encoding != REDIS_ENCODING_HT);
+    p = zipmapRewind(zm);
+    while((p = zipmapNext(p,&key,&klen,&val,&vlen)) != NULL) {
+        robj *keyobj, *valobj;
+
+        keyobj = createStringObject((char*)key,klen);
+        valobj = createStringObject((char*)val,vlen);
+        keyobj = tryObjectEncoding(keyobj);
+        valobj = tryObjectEncoding(valobj);
+        dictAdd(dict,keyobj,valobj);
+    }
+    o->encoding = REDIS_ENCODING_HT;
+    o->ptr = dict;
+    zfree(zm);
+}
+
+/*-----------------------------------------------------------------------------
+ * Hash type commands
+ *----------------------------------------------------------------------------*/
+
+void hsetCommand(redisClient *c) {
+    int update;
+    robj *o;
+
+    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
+    hashTypeTryConversion(o,c->argv,2,3);
+    hashTypeTryObjectEncoding(o,&c->argv[2], &c->argv[3]);
+    update = hashTypeSet(o,c->argv[2],c->argv[3]);
+    addReply(c, update ? shared.czero : shared.cone);
+    server.dirty++;
+}
+
+void hsetnxCommand(redisClient *c) {
+    robj *o;
+    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
+    hashTypeTryConversion(o,c->argv,2,3);
+
+    if (hashTypeExists(o, c->argv[2])) {
+        addReply(c, shared.czero);
+    } else {
+        hashTypeTryObjectEncoding(o,&c->argv[2], &c->argv[3]);
+        hashTypeSet(o,c->argv[2],c->argv[3]);
+        addReply(c, shared.cone);
+        server.dirty++;
+    }
+}
+
+void hmsetCommand(redisClient *c) {
+    int i;
+    robj *o;
+
+    if ((c->argc % 2) == 1) {
+        addReplySds(c,sdsnew("-ERR wrong number of arguments for HMSET\r\n"));
+        return;
+    }
+
+    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
+    hashTypeTryConversion(o,c->argv,2,c->argc-1);
+    for (i = 2; i < c->argc; i += 2) {
+        hashTypeTryObjectEncoding(o,&c->argv[i], &c->argv[i+1]);
+        hashTypeSet(o,c->argv[i],c->argv[i+1]);
+    }
+    addReply(c, shared.ok);
+    server.dirty++;
+}
+
+void hincrbyCommand(redisClient *c) {
+    long long value, incr;
+    robj *o, *current, *new;
+
+    if (getLongLongFromObjectOrReply(c,c->argv[3],&incr,NULL) != REDIS_OK) return;
+    if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
+    if ((current = hashTypeGet(o,c->argv[2])) != NULL) {
+        if (getLongLongFromObjectOrReply(c,current,&value,
+            "hash value is not an integer") != REDIS_OK) {
+            decrRefCount(current);
+            return;
+        }
+        decrRefCount(current);
+    } else {
+        value = 0;
+    }
+
+    value += incr;
+    new = createStringObjectFromLongLong(value);
+    hashTypeTryObjectEncoding(o,&c->argv[2],NULL);
+    hashTypeSet(o,c->argv[2],new);
+    decrRefCount(new);
+    addReplyLongLong(c,value);
+    server.dirty++;
+}
+
+void hgetCommand(redisClient *c) {
+    robj *o, *value;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,o,REDIS_HASH)) return;
+
+    if ((value = hashTypeGet(o,c->argv[2])) != NULL) {
+        addReplyBulk(c,value);
+        decrRefCount(value);
+    } else {
+        addReply(c,shared.nullbulk);
+    }
+}
+
+void hmgetCommand(redisClient *c) {
+    int i;
+    robj *o, *value;
+    o = lookupKeyRead(c->db,c->argv[1]);
+    if (o != NULL && o->type != REDIS_HASH) {
+        addReply(c,shared.wrongtypeerr);
+    }
+
+    /* Note the check for o != NULL happens inside the loop. This is
+     * done because objects that cannot be found are considered to be
+     * an empty hash. The reply should then be a series of NULLs. */
+    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",c->argc-2));
+    for (i = 2; i < c->argc; i++) {
+        if (o != NULL && (value = hashTypeGet(o,c->argv[i])) != NULL) {
+            addReplyBulk(c,value);
+            decrRefCount(value);
+        } else {
+            addReply(c,shared.nullbulk);
+        }
+    }
+}
+
+void hdelCommand(redisClient *c) {
+    robj *o;
+    if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,o,REDIS_HASH)) return;
+
+    if (hashTypeDelete(o,c->argv[2])) {
+        if (hashTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
+        addReply(c,shared.cone);
+        server.dirty++;
+    } else {
+        addReply(c,shared.czero);
+    }
+}
+
+void hlenCommand(redisClient *c) {
+    robj *o;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,o,REDIS_HASH)) return;
+
+    addReplyUlong(c,hashTypeLength(o));
+}
+
+void genericHgetallCommand(redisClient *c, int flags) {
+    robj *o, *lenobj, *obj;
+    unsigned long count = 0;
+    hashTypeIterator *hi;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
+        || checkType(c,o,REDIS_HASH)) return;
+
+    lenobj = createObject(REDIS_STRING,NULL);
+    addReply(c,lenobj);
+    decrRefCount(lenobj);
+
+    hi = hashTypeInitIterator(o);
+    while (hashTypeNext(hi) != REDIS_ERR) {
+        if (flags & REDIS_HASH_KEY) {
+            obj = hashTypeCurrent(hi,REDIS_HASH_KEY);
+            addReplyBulk(c,obj);
+            decrRefCount(obj);
+            count++;
+        }
+        if (flags & REDIS_HASH_VALUE) {
+            obj = hashTypeCurrent(hi,REDIS_HASH_VALUE);
+            addReplyBulk(c,obj);
+            decrRefCount(obj);
+            count++;
+        }
+    }
+    hashTypeReleaseIterator(hi);
+
+    lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",count);
+}
+
+void hkeysCommand(redisClient *c) {
+    genericHgetallCommand(c,REDIS_HASH_KEY);
+}
+
+void hvalsCommand(redisClient *c) {
+    genericHgetallCommand(c,REDIS_HASH_VALUE);
+}
+
+void hgetallCommand(redisClient *c) {
+    genericHgetallCommand(c,REDIS_HASH_KEY|REDIS_HASH_VALUE);
+}
+
+void hexistsCommand(redisClient *c) {
+    robj *o;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,o,REDIS_HASH)) return;
+
+    addReply(c, hashTypeExists(o,c->argv[2]) ? shared.cone : shared.czero);
+}

src/t_list.c

@@ -0,0 +1,829 @@
+#include "redis.h"
+
+/*-----------------------------------------------------------------------------
+ * List API
+ *----------------------------------------------------------------------------*/
+
+/* Check the argument length to see if it requires us to convert the ziplist
+ * to a real list. Only check raw-encoded objects because integer encoded
+ * objects are never too long. */
+void listTypeTryConversion(robj *subject, robj *value) {
+    if (subject->encoding != REDIS_ENCODING_ZIPLIST) return;
+    if (value->encoding == REDIS_ENCODING_RAW &&
+        sdslen(value->ptr) > server.list_max_ziplist_value)
+            listTypeConvert(subject,REDIS_ENCODING_LINKEDLIST);
+}
+
+void listTypePush(robj *subject, robj *value, int where) {
+    /* Check if we need to convert the ziplist */
+    listTypeTryConversion(subject,value);
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST &&
+        ziplistLen(subject->ptr) >= server.list_max_ziplist_entries)
+            listTypeConvert(subject,REDIS_ENCODING_LINKEDLIST);
+
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST) {
+        int pos = (where == REDIS_HEAD) ? ZIPLIST_HEAD : ZIPLIST_TAIL;
+        value = getDecodedObject(value);
+        subject->ptr = ziplistPush(subject->ptr,value->ptr,sdslen(value->ptr),pos);
+        decrRefCount(value);
+    } else if (subject->encoding == REDIS_ENCODING_LINKEDLIST) {
+        if (where == REDIS_HEAD) {
+            listAddNodeHead(subject->ptr,value);
+        } else {
+            listAddNodeTail(subject->ptr,value);
+        }
+        incrRefCount(value);
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+robj *listTypePop(robj *subject, int where) {
+    robj *value = NULL;
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *p;
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vlong;
+        int pos = (where == REDIS_HEAD) ? 0 : -1;
+        p = ziplistIndex(subject->ptr,pos);
+        if (ziplistGet(p,&vstr,&vlen,&vlong)) {
+            if (vstr) {
+                value = createStringObject((char*)vstr,vlen);
+            } else {
+                value = createStringObjectFromLongLong(vlong);
+            }
+            /* We only need to delete an element when it exists */
+            subject->ptr = ziplistDelete(subject->ptr,&p);
+        }
+    } else if (subject->encoding == REDIS_ENCODING_LINKEDLIST) {
+        list *list = subject->ptr;
+        listNode *ln;
+        if (where == REDIS_HEAD) {
+            ln = listFirst(list);
+        } else {
+            ln = listLast(list);
+        }
+        if (ln != NULL) {
+            value = listNodeValue(ln);
+            incrRefCount(value);
+            listDelNode(list,ln);
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    return value;
+}
+
+unsigned long listTypeLength(robj *subject) {
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST) {
+        return ziplistLen(subject->ptr);
+    } else if (subject->encoding == REDIS_ENCODING_LINKEDLIST) {
+        return listLength((list*)subject->ptr);
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+/* Initialize an iterator at the specified index. */
+listTypeIterator *listTypeInitIterator(robj *subject, int index, unsigned char direction) {
+    listTypeIterator *li = zmalloc(sizeof(listTypeIterator));
+    li->subject = subject;
+    li->encoding = subject->encoding;
+    li->direction = direction;
+    if (li->encoding == REDIS_ENCODING_ZIPLIST) {
+        li->zi = ziplistIndex(subject->ptr,index);
+    } else if (li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        li->ln = listIndex(subject->ptr,index);
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    return li;
+}
+
+/* Clean up the iterator. */
+void listTypeReleaseIterator(listTypeIterator *li) {
+    zfree(li);
+}
+
+/* Stores pointer to current the entry in the provided entry structure
+ * and advances the position of the iterator. Returns 1 when the current
+ * entry is in fact an entry, 0 otherwise. */
+int listTypeNext(listTypeIterator *li, listTypeEntry *entry) {
+    /* Protect from converting when iterating */
+    redisAssert(li->subject->encoding == li->encoding);
+
+    entry->li = li;
+    if (li->encoding == REDIS_ENCODING_ZIPLIST) {
+        entry->zi = li->zi;
+        if (entry->zi != NULL) {
+            if (li->direction == REDIS_TAIL)
+                li->zi = ziplistNext(li->subject->ptr,li->zi);
+            else
+                li->zi = ziplistPrev(li->subject->ptr,li->zi);
+            return 1;
+        }
+    } else if (li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        entry->ln = li->ln;
+        if (entry->ln != NULL) {
+            if (li->direction == REDIS_TAIL)
+                li->ln = li->ln->next;
+            else
+                li->ln = li->ln->prev;
+            return 1;
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    return 0;
+}
+
+/* Return entry or NULL at the current position of the iterator. */
+robj *listTypeGet(listTypeEntry *entry) {
+    listTypeIterator *li = entry->li;
+    robj *value = NULL;
+    if (li->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vlong;
+        redisAssert(entry->zi != NULL);
+        if (ziplistGet(entry->zi,&vstr,&vlen,&vlong)) {
+            if (vstr) {
+                value = createStringObject((char*)vstr,vlen);
+            } else {
+                value = createStringObjectFromLongLong(vlong);
+            }
+        }
+    } else if (li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        redisAssert(entry->ln != NULL);
+        value = listNodeValue(entry->ln);
+        incrRefCount(value);
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    return value;
+}
+
+void listTypeInsert(listTypeEntry *entry, robj *value, int where) {
+    robj *subject = entry->li->subject;
+    if (entry->li->encoding == REDIS_ENCODING_ZIPLIST) {
+        value = getDecodedObject(value);
+        if (where == REDIS_TAIL) {
+            unsigned char *next = ziplistNext(subject->ptr,entry->zi);
+
+            /* When we insert after the current element, but the current element
+             * is the tail of the list, we need to do a push. */
+            if (next == NULL) {
+                subject->ptr = ziplistPush(subject->ptr,value->ptr,sdslen(value->ptr),REDIS_TAIL);
+            } else {
+                subject->ptr = ziplistInsert(subject->ptr,next,value->ptr,sdslen(value->ptr));
+            }
+        } else {
+            subject->ptr = ziplistInsert(subject->ptr,entry->zi,value->ptr,sdslen(value->ptr));
+        }
+        decrRefCount(value);
+    } else if (entry->li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        if (where == REDIS_TAIL) {
+            listInsertNode(subject->ptr,entry->ln,value,AL_START_TAIL);
+        } else {
+            listInsertNode(subject->ptr,entry->ln,value,AL_START_HEAD);
+        }
+        incrRefCount(value);
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+/* Compare the given object with the entry at the current position. */
+int listTypeEqual(listTypeEntry *entry, robj *o) {
+    listTypeIterator *li = entry->li;
+    if (li->encoding == REDIS_ENCODING_ZIPLIST) {
+        redisAssert(o->encoding == REDIS_ENCODING_RAW);
+        return ziplistCompare(entry->zi,o->ptr,sdslen(o->ptr));
+    } else if (li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        return equalStringObjects(o,listNodeValue(entry->ln));
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+/* Delete the element pointed to. */
+void listTypeDelete(listTypeEntry *entry) {
+    listTypeIterator *li = entry->li;
+    if (li->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *p = entry->zi;
+        li->subject->ptr = ziplistDelete(li->subject->ptr,&p);
+
+        /* Update position of the iterator depending on the direction */
+        if (li->direction == REDIS_TAIL)
+            li->zi = p;
+        else
+            li->zi = ziplistPrev(li->subject->ptr,p);
+    } else if (entry->li->encoding == REDIS_ENCODING_LINKEDLIST) {
+        listNode *next;
+        if (li->direction == REDIS_TAIL)
+            next = entry->ln->next;
+        else
+            next = entry->ln->prev;
+        listDelNode(li->subject->ptr,entry->ln);
+        li->ln = next;
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+void listTypeConvert(robj *subject, int enc) {
+    listTypeIterator *li;
+    listTypeEntry entry;
+    redisAssert(subject->type == REDIS_LIST);
+
+    if (enc == REDIS_ENCODING_LINKEDLIST) {
+        list *l = listCreate();
+        listSetFreeMethod(l,decrRefCount);
+
+        /* listTypeGet returns a robj with incremented refcount */
+        li = listTypeInitIterator(subject,0,REDIS_TAIL);
+        while (listTypeNext(li,&entry)) listAddNodeTail(l,listTypeGet(&entry));
+        listTypeReleaseIterator(li);
+
+        subject->encoding = REDIS_ENCODING_LINKEDLIST;
+        zfree(subject->ptr);
+        subject->ptr = l;
+    } else {
+        redisPanic("Unsupported list conversion");
+    }
+}
+
+/*-----------------------------------------------------------------------------
+ * List Commands
+ *----------------------------------------------------------------------------*/
+
+void pushGenericCommand(redisClient *c, int where) {
+    robj *lobj = lookupKeyWrite(c->db,c->argv[1]);
+    if (lobj == NULL) {
+        if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
+            addReply(c,shared.cone);
+            return;
+        }
+        lobj = createZiplistObject();
+        dbAdd(c->db,c->argv[1],lobj);
+    } else {
+        if (lobj->type != REDIS_LIST) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+        if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
+            addReply(c,shared.cone);
+            return;
+        }
+    }
+    listTypePush(lobj,c->argv[2],where);
+    addReplyLongLong(c,listTypeLength(lobj));
+    server.dirty++;
+}
+
+void lpushCommand(redisClient *c) {
+    pushGenericCommand(c,REDIS_HEAD);
+}
+
+void rpushCommand(redisClient *c) {
+    pushGenericCommand(c,REDIS_TAIL);
+}
+
+void pushxGenericCommand(redisClient *c, robj *refval, robj *val, int where) {
+    robj *subject;
+    listTypeIterator *iter;
+    listTypeEntry entry;
+    int inserted = 0;
+
+    if ((subject = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,subject,REDIS_LIST)) return;
+
+    if (refval != NULL) {
+        /* Note: we expect refval to be string-encoded because it is *not* the
+         * last argument of the multi-bulk LINSERT. */
+        redisAssert(refval->encoding == REDIS_ENCODING_RAW);
+
+        /* We're not sure if this value can be inserted yet, but we cannot
+         * convert the list inside the iterator. We don't want to loop over
+         * the list twice (once to see if the value can be inserted and once
+         * to do the actual insert), so we assume this value can be inserted
+         * and convert the ziplist to a regular list if necessary. */
+        listTypeTryConversion(subject,val);
+
+        /* Seek refval from head to tail */
+        iter = listTypeInitIterator(subject,0,REDIS_TAIL);
+        while (listTypeNext(iter,&entry)) {
+            if (listTypeEqual(&entry,refval)) {
+                listTypeInsert(&entry,val,where);
+                inserted = 1;
+                break;
+            }
+        }
+        listTypeReleaseIterator(iter);
+
+        if (inserted) {
+            /* Check if the length exceeds the ziplist length threshold. */
+            if (subject->encoding == REDIS_ENCODING_ZIPLIST &&
+                ziplistLen(subject->ptr) > server.list_max_ziplist_entries)
+                    listTypeConvert(subject,REDIS_ENCODING_LINKEDLIST);
+            server.dirty++;
+        } else {
+            /* Notify client of a failed insert */
+            addReply(c,shared.cnegone);
+            return;
+        }
+    } else {
+        listTypePush(subject,val,where);
+        server.dirty++;
+    }
+
+    addReplyUlong(c,listTypeLength(subject));
+}
+
+void lpushxCommand(redisClient *c) {
+    pushxGenericCommand(c,NULL,c->argv[2],REDIS_HEAD);
+}
+
+void rpushxCommand(redisClient *c) {
+    pushxGenericCommand(c,NULL,c->argv[2],REDIS_TAIL);
+}
+
+void linsertCommand(redisClient *c) {
+    if (strcasecmp(c->argv[2]->ptr,"after") == 0) {
+        pushxGenericCommand(c,c->argv[3],c->argv[4],REDIS_TAIL);
+    } else if (strcasecmp(c->argv[2]->ptr,"before") == 0) {
+        pushxGenericCommand(c,c->argv[3],c->argv[4],REDIS_HEAD);
+    } else {
+        addReply(c,shared.syntaxerr);
+    }
+}
+
+void llenCommand(redisClient *c) {
+    robj *o = lookupKeyReadOrReply(c,c->argv[1],shared.czero);
+    if (o == NULL || checkType(c,o,REDIS_LIST)) return;
+    addReplyUlong(c,listTypeLength(o));
+}
+
+void lindexCommand(redisClient *c) {
+    robj *o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk);
+    if (o == NULL || checkType(c,o,REDIS_LIST)) return;
+    int index = atoi(c->argv[2]->ptr);
+    robj *value = NULL;
+
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *p;
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vlong;
+        p = ziplistIndex(o->ptr,index);
+        if (ziplistGet(p,&vstr,&vlen,&vlong)) {
+            if (vstr) {
+                value = createStringObject((char*)vstr,vlen);
+            } else {
+                value = createStringObjectFromLongLong(vlong);
+            }
+            addReplyBulk(c,value);
+            decrRefCount(value);
+        } else {
+            addReply(c,shared.nullbulk);
+        }
+    } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+        listNode *ln = listIndex(o->ptr,index);
+        if (ln != NULL) {
+            value = listNodeValue(ln);
+            addReplyBulk(c,value);
+        } else {
+            addReply(c,shared.nullbulk);
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+void lsetCommand(redisClient *c) {
+    robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr);
+    if (o == NULL || checkType(c,o,REDIS_LIST)) return;
+    int index = atoi(c->argv[2]->ptr);
+    robj *value = c->argv[3];
+
+    listTypeTryConversion(o,value);
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *p, *zl = o->ptr;
+        p = ziplistIndex(zl,index);
+        if (p == NULL) {
+            addReply(c,shared.outofrangeerr);
+        } else {
+            o->ptr = ziplistDelete(o->ptr,&p);
+            value = getDecodedObject(value);
+            o->ptr = ziplistInsert(o->ptr,p,value->ptr,sdslen(value->ptr));
+            decrRefCount(value);
+            addReply(c,shared.ok);
+            server.dirty++;
+        }
+    } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+        listNode *ln = listIndex(o->ptr,index);
+        if (ln == NULL) {
+            addReply(c,shared.outofrangeerr);
+        } else {
+            decrRefCount((robj*)listNodeValue(ln));
+            listNodeValue(ln) = value;
+            incrRefCount(value);
+            addReply(c,shared.ok);
+            server.dirty++;
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+}
+
+void popGenericCommand(redisClient *c, int where) {
+    robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk);
+    if (o == NULL || checkType(c,o,REDIS_LIST)) return;
+
+    robj *value = listTypePop(o,where);
+    if (value == NULL) {
+        addReply(c,shared.nullbulk);
+    } else {
+        addReplyBulk(c,value);
+        decrRefCount(value);
+        if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
+        server.dirty++;
+    }
+}
+
+void lpopCommand(redisClient *c) {
+    popGenericCommand(c,REDIS_HEAD);
+}
+
+void rpopCommand(redisClient *c) {
+    popGenericCommand(c,REDIS_TAIL);
+}
+
+void lrangeCommand(redisClient *c) {
+    robj *o, *value;
+    int start = atoi(c->argv[2]->ptr);
+    int end = atoi(c->argv[3]->ptr);
+    int llen;
+    int rangelen, j;
+    listTypeEntry entry;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
+         || checkType(c,o,REDIS_LIST)) return;
+    llen = listTypeLength(o);
+
+    /* convert negative indexes */
+    if (start < 0) start = llen+start;
+    if (end < 0) end = llen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+
+    /* indexes sanity checks */
+    if (start > end || start >= llen) {
+        /* Out of range start or start > end result in empty list */
+        addReply(c,shared.emptymultibulk);
+        return;
+    }
+    if (end >= llen) end = llen-1;
+    rangelen = (end-start)+1;
+
+    /* Return the result in form of a multi-bulk reply */
+    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",rangelen));
+    listTypeIterator *li = listTypeInitIterator(o,start,REDIS_TAIL);
+    for (j = 0; j < rangelen; j++) {
+        redisAssert(listTypeNext(li,&entry));
+        value = listTypeGet(&entry);
+        addReplyBulk(c,value);
+        decrRefCount(value);
+    }
+    listTypeReleaseIterator(li);
+}
+
+void ltrimCommand(redisClient *c) {
+    robj *o;
+    int start = atoi(c->argv[2]->ptr);
+    int end = atoi(c->argv[3]->ptr);
+    int llen;
+    int j, ltrim, rtrim;
+    list *list;
+    listNode *ln;
+
+    if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.ok)) == NULL ||
+        checkType(c,o,REDIS_LIST)) return;
+    llen = listTypeLength(o);
+
+    /* convert negative indexes */
+    if (start < 0) start = llen+start;
+    if (end < 0) end = llen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+
+    /* indexes sanity checks */
+    if (start > end || start >= llen) {
+        /* Out of range start or start > end result in empty list */
+        ltrim = llen;
+        rtrim = 0;
+    } else {
+        if (end >= llen) end = llen-1;
+        ltrim = start;
+        rtrim = llen-end-1;
+    }
+
+    /* Remove list elements to perform the trim */
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        o->ptr = ziplistDeleteRange(o->ptr,0,ltrim);
+        o->ptr = ziplistDeleteRange(o->ptr,-rtrim,rtrim);
+    } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+        list = o->ptr;
+        for (j = 0; j < ltrim; j++) {
+            ln = listFirst(list);
+            listDelNode(list,ln);
+        }
+        for (j = 0; j < rtrim; j++) {
+            ln = listLast(list);
+            listDelNode(list,ln);
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
+    server.dirty++;
+    addReply(c,shared.ok);
+}
+
+void lremCommand(redisClient *c) {
+    robj *subject, *obj = c->argv[3];
+    int toremove = atoi(c->argv[2]->ptr);
+    int removed = 0;
+    listTypeEntry entry;
+
+    subject = lookupKeyWriteOrReply(c,c->argv[1],shared.czero);
+    if (subject == NULL || checkType(c,subject,REDIS_LIST)) return;
+
+    /* Make sure obj is raw when we're dealing with a ziplist */
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST)
+        obj = getDecodedObject(obj);
+
+    listTypeIterator *li;
+    if (toremove < 0) {
+        toremove = -toremove;
+        li = listTypeInitIterator(subject,-1,REDIS_HEAD);
+    } else {
+        li = listTypeInitIterator(subject,0,REDIS_TAIL);
+    }
+
+    while (listTypeNext(li,&entry)) {
+        if (listTypeEqual(&entry,obj)) {
+            listTypeDelete(&entry);
+            server.dirty++;
+            removed++;
+            if (toremove && removed == toremove) break;
+        }
+    }
+    listTypeReleaseIterator(li);
+
+    /* Clean up raw encoded object */
+    if (subject->encoding == REDIS_ENCODING_ZIPLIST)
+        decrRefCount(obj);
+
+    if (listTypeLength(subject) == 0) dbDelete(c->db,c->argv[1]);
+    addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",removed));
+}
+
+/* This is the semantic of this command:
+ *  RPOPLPUSH srclist dstlist:
+ *   IF LLEN(srclist) > 0
+ *     element = RPOP srclist
+ *     LPUSH dstlist element
+ *     RETURN element
+ *   ELSE
+ *     RETURN nil
+ *   END
+ *  END
+ *
+ * The idea is to be able to get an element from a list in a reliable way
+ * since the element is not just returned but pushed against another list
+ * as well. This command was originally proposed by Ezra Zygmuntowicz.
+ */
+void rpoplpushcommand(redisClient *c) {
+    robj *sobj, *value;
+    if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,sobj,REDIS_LIST)) return;
+
+    if (listTypeLength(sobj) == 0) {
+        addReply(c,shared.nullbulk);
+    } else {
+        robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
+        if (dobj && checkType(c,dobj,REDIS_LIST)) return;
+        value = listTypePop(sobj,REDIS_TAIL);
+
+        /* Add the element to the target list (unless it's directly
+         * passed to some BLPOP-ing client */
+        if (!handleClientsWaitingListPush(c,c->argv[2],value)) {
+            /* Create the list if the key does not exist */
+            if (!dobj) {
+                dobj = createZiplistObject();
+                dbAdd(c->db,c->argv[2],dobj);
+            }
+            listTypePush(dobj,value,REDIS_HEAD);
+        }
+
+        /* Send the element to the client as reply as well */
+        addReplyBulk(c,value);
+
+        /* listTypePop returns an object with its refcount incremented */
+        decrRefCount(value);
+
+        /* Delete the source list when it is empty */
+        if (listTypeLength(sobj) == 0) dbDelete(c->db,c->argv[1]);
+        server.dirty++;
+    }
+}
+
+/*-----------------------------------------------------------------------------
+ * Blocking POP operations
+ *----------------------------------------------------------------------------*/
+
+/* Currently Redis blocking operations support is limited to list POP ops,
+ * so the current implementation is not fully generic, but it is also not
+ * completely specific so it will not require a rewrite to support new
+ * kind of blocking operations in the future.
+ *
+ * Still it's important to note that list blocking operations can be already
+ * used as a notification mechanism in order to implement other blocking
+ * operations at application level, so there must be a very strong evidence
+ * of usefulness and generality before new blocking operations are implemented.
+ *
+ * This is how the current blocking POP works, we use BLPOP as example:
+ * - If the user calls BLPOP and the key exists and contains a non empty list
+ *   then LPOP is called instead. So BLPOP is semantically the same as LPOP
+ *   if there is not to block.
+ * - If instead BLPOP is called and the key does not exists or the list is
+ *   empty we need to block. In order to do so we remove the notification for
+ *   new data to read in the client socket (so that we'll not serve new
+ *   requests if the blocking request is not served). Also we put the client
+ *   in a dictionary (db->blocking_keys) mapping keys to a list of clients
+ *   blocking for this keys.
+ * - If a PUSH operation against a key with blocked clients waiting is
+ *   performed, we serve the first in the list: basically instead to push
+ *   the new element inside the list we return it to the (first / oldest)
+ *   blocking client, unblock the client, and remove it form the list.
+ *
+ * The above comment and the source code should be enough in order to understand
+ * the implementation and modify / fix it later.
+ */
+
+/* Set a client in blocking mode for the specified key, with the specified
+ * timeout */
+void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout) {
+    dictEntry *de;
+    list *l;
+    int j;
+
+    c->blocking_keys = zmalloc(sizeof(robj*)*numkeys);
+    c->blocking_keys_num = numkeys;
+    c->blockingto = timeout;
+    for (j = 0; j < numkeys; j++) {
+        /* Add the key in the client structure, to map clients -> keys */
+        c->blocking_keys[j] = keys[j];
+        incrRefCount(keys[j]);
+
+        /* And in the other "side", to map keys -> clients */
+        de = dictFind(c->db->blocking_keys,keys[j]);
+        if (de == NULL) {
+            int retval;
+
+            /* For every key we take a list of clients blocked for it */
+            l = listCreate();
+            retval = dictAdd(c->db->blocking_keys,keys[j],l);
+            incrRefCount(keys[j]);
+            redisAssert(retval == DICT_OK);
+        } else {
+            l = dictGetEntryVal(de);
+        }
+        listAddNodeTail(l,c);
+    }
+    /* Mark the client as a blocked client */
+    c->flags |= REDIS_BLOCKED;
+    server.blpop_blocked_clients++;
+}
+
+/* Unblock a client that's waiting in a blocking operation such as BLPOP */
+void unblockClientWaitingData(redisClient *c) {
+    dictEntry *de;
+    list *l;
+    int j;
+
+    redisAssert(c->blocking_keys != NULL);
+    /* The client may wait for multiple keys, so unblock it for every key. */
+    for (j = 0; j < c->blocking_keys_num; j++) {
+        /* Remove this client from the list of clients waiting for this key. */
+        de = dictFind(c->db->blocking_keys,c->blocking_keys[j]);
+        redisAssert(de != NULL);
+        l = dictGetEntryVal(de);
+        listDelNode(l,listSearchKey(l,c));
+        /* If the list is empty we need to remove it to avoid wasting memory */
+        if (listLength(l) == 0)
+            dictDelete(c->db->blocking_keys,c->blocking_keys[j]);
+        decrRefCount(c->blocking_keys[j]);
+    }
+    /* Cleanup the client structure */
+    zfree(c->blocking_keys);
+    c->blocking_keys = NULL;
+    c->flags &= (~REDIS_BLOCKED);
+    server.blpop_blocked_clients--;
+    /* We want to process data if there is some command waiting
+     * in the input buffer. Note that this is safe even if
+     * unblockClientWaitingData() gets called from freeClient() because
+     * freeClient() will be smart enough to call this function
+     * *after* c->querybuf was set to NULL. */
+    if (c->querybuf && sdslen(c->querybuf) > 0) processInputBuffer(c);
+}
+
+/* This should be called from any function PUSHing into lists.
+ * 'c' is the "pushing client", 'key' is the key it is pushing data against,
+ * 'ele' is the element pushed.
+ *
+ * If the function returns 0 there was no client waiting for a list push
+ * against this key.
+ *
+ * If the function returns 1 there was a client waiting for a list push
+ * against this key, the element was passed to this client thus it's not
+ * needed to actually add it to the list and the caller should return asap. */
+int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele) {
+    struct dictEntry *de;
+    redisClient *receiver;
+    list *l;
+    listNode *ln;
+
+    de = dictFind(c->db->blocking_keys,key);
+    if (de == NULL) return 0;
+    l = dictGetEntryVal(de);
+    ln = listFirst(l);
+    redisAssert(ln != NULL);
+    receiver = ln->value;
+
+    addReplySds(receiver,sdsnew("*2\r\n"));
+    addReplyBulk(receiver,key);
+    addReplyBulk(receiver,ele);
+    unblockClientWaitingData(receiver);
+    return 1;
+}
+
+/* Blocking RPOP/LPOP */
+void blockingPopGenericCommand(redisClient *c, int where) {
+    robj *o;
+    time_t timeout;
+    int j;
+
+    for (j = 1; j < c->argc-1; j++) {
+        o = lookupKeyWrite(c->db,c->argv[j]);
+        if (o != NULL) {
+            if (o->type != REDIS_LIST) {
+                addReply(c,shared.wrongtypeerr);
+                return;
+            } else {
+                if (listTypeLength(o) != 0) {
+                    /* If the list contains elements fall back to the usual
+                     * non-blocking POP operation */
+                    robj *argv[2], **orig_argv;
+                    int orig_argc;
+
+                    /* We need to alter the command arguments before to call
+                     * popGenericCommand() as the command takes a single key. */
+                    orig_argv = c->argv;
+                    orig_argc = c->argc;
+                    argv[1] = c->argv[j];
+                    c->argv = argv;
+                    c->argc = 2;
+
+                    /* Also the return value is different, we need to output
+                     * the multi bulk reply header and the key name. The
+                     * "real" command will add the last element (the value)
+                     * for us. If this souds like an hack to you it's just
+                     * because it is... */
+                    addReplySds(c,sdsnew("*2\r\n"));
+                    addReplyBulk(c,argv[1]);
+                    popGenericCommand(c,where);
+
+                    /* Fix the client structure with the original stuff */
+                    c->argv = orig_argv;
+                    c->argc = orig_argc;
+                    return;
+                }
+            }
+        }
+    }
+    /* If the list is empty or the key does not exists we must block */
+    timeout = strtol(c->argv[c->argc-1]->ptr,NULL,10);
+    if (timeout > 0) timeout += time(NULL);
+    blockForKeys(c,c->argv+1,c->argc-2,timeout);
+}
+
+void blpopCommand(redisClient *c) {
+    blockingPopGenericCommand(c,REDIS_HEAD);
+}
+
+void brpopCommand(redisClient *c) {
+    blockingPopGenericCommand(c,REDIS_TAIL);
+}

src/t_set.c

@@ -0,0 +1,349 @@
+#include "redis.h"
+
+/*-----------------------------------------------------------------------------
+ * Set Commands
+ *----------------------------------------------------------------------------*/
+
+void saddCommand(redisClient *c) {
+    robj *set;
+
+    set = lookupKeyWrite(c->db,c->argv[1]);
+    if (set == NULL) {
+        set = createSetObject();
+        dbAdd(c->db,c->argv[1],set);
+    } else {
+        if (set->type != REDIS_SET) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+    }
+    if (dictAdd(set->ptr,c->argv[2],NULL) == DICT_OK) {
+        incrRefCount(c->argv[2]);
+        server.dirty++;
+        addReply(c,shared.cone);
+    } else {
+        addReply(c,shared.czero);
+    }
+}
+
+void sremCommand(redisClient *c) {
+    robj *set;
+
+    if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,set,REDIS_SET)) return;
+
+    if (dictDelete(set->ptr,c->argv[2]) == DICT_OK) {
+        server.dirty++;
+        if (htNeedsResize(set->ptr)) dictResize(set->ptr);
+        if (dictSize((dict*)set->ptr) == 0) dbDelete(c->db,c->argv[1]);
+        addReply(c,shared.cone);
+    } else {
+        addReply(c,shared.czero);
+    }
+}
+
+void smoveCommand(redisClient *c) {
+    robj *srcset, *dstset;
+
+    srcset = lookupKeyWrite(c->db,c->argv[1]);
+    dstset = lookupKeyWrite(c->db,c->argv[2]);
+
+    /* If the source key does not exist return 0, if it's of the wrong type
+     * raise an error */
+    if (srcset == NULL || srcset->type != REDIS_SET) {
+        addReply(c, srcset ? shared.wrongtypeerr : shared.czero);
+        return;
+    }
+    /* Error if the destination key is not a set as well */
+    if (dstset && dstset->type != REDIS_SET) {
+        addReply(c,shared.wrongtypeerr);
+        return;
+    }
+    /* Remove the element from the source set */
+    if (dictDelete(srcset->ptr,c->argv[3]) == DICT_ERR) {
+        /* Key not found in the src set! return zero */
+        addReply(c,shared.czero);
+        return;
+    }
+    if (dictSize((dict*)srcset->ptr) == 0 && srcset != dstset)
+        dbDelete(c->db,c->argv[1]);
+    server.dirty++;
+    /* Add the element to the destination set */
+    if (!dstset) {
+        dstset = createSetObject();
+        dbAdd(c->db,c->argv[2],dstset);
+    }
+    if (dictAdd(dstset->ptr,c->argv[3],NULL) == DICT_OK)
+        incrRefCount(c->argv[3]);
+    addReply(c,shared.cone);
+}
+
+void sismemberCommand(redisClient *c) {
+    robj *set;
+
+    if ((set = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,set,REDIS_SET)) return;
+
+    if (dictFind(set->ptr,c->argv[2]))
+        addReply(c,shared.cone);
+    else
+        addReply(c,shared.czero);
+}
+
+void scardCommand(redisClient *c) {
+    robj *o;
+    dict *s;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,o,REDIS_SET)) return;
+
+    s = o->ptr;
+    addReplyUlong(c,dictSize(s));
+}
+
+void spopCommand(redisClient *c) {
+    robj *set;
+    dictEntry *de;
+
+    if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,set,REDIS_SET)) return;
+
+    de = dictGetRandomKey(set->ptr);
+    if (de == NULL) {
+        addReply(c,shared.nullbulk);
+    } else {
+        robj *ele = dictGetEntryKey(de);
+
+        addReplyBulk(c,ele);
+        dictDelete(set->ptr,ele);
+        if (htNeedsResize(set->ptr)) dictResize(set->ptr);
+        if (dictSize((dict*)set->ptr) == 0) dbDelete(c->db,c->argv[1]);
+        server.dirty++;
+    }
+}
+
+void srandmemberCommand(redisClient *c) {
+    robj *set;
+    dictEntry *de;
+
+    if ((set = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,set,REDIS_SET)) return;
+
+    de = dictGetRandomKey(set->ptr);
+    if (de == NULL) {
+        addReply(c,shared.nullbulk);
+    } else {
+        robj *ele = dictGetEntryKey(de);
+
+        addReplyBulk(c,ele);
+    }
+}
+
+int qsortCompareSetsByCardinality(const void *s1, const void *s2) {
+    dict **d1 = (void*) s1, **d2 = (void*) s2;
+
+    return dictSize(*d1)-dictSize(*d2);
+}
+
+void sinterGenericCommand(redisClient *c, robj **setskeys, unsigned long setsnum, robj *dstkey) {
+    dict **dv = zmalloc(sizeof(dict*)*setsnum);
+    dictIterator *di;
+    dictEntry *de;
+    robj *lenobj = NULL, *dstset = NULL;
+    unsigned long j, cardinality = 0;
+
+    for (j = 0; j < setsnum; j++) {
+        robj *setobj;
+
+        setobj = dstkey ?
+                    lookupKeyWrite(c->db,setskeys[j]) :
+                    lookupKeyRead(c->db,setskeys[j]);
+        if (!setobj) {
+            zfree(dv);
+            if (dstkey) {
+                if (dbDelete(c->db,dstkey))
+                    server.dirty++;
+                addReply(c,shared.czero);
+            } else {
+                addReply(c,shared.emptymultibulk);
+            }
+            return;
+        }
+        if (setobj->type != REDIS_SET) {
+            zfree(dv);
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+        dv[j] = setobj->ptr;
+    }
+    /* Sort sets from the smallest to largest, this will improve our
+     * algorithm's performace */
+    qsort(dv,setsnum,sizeof(dict*),qsortCompareSetsByCardinality);
+
+    /* The first thing we should output is the total number of elements...
+     * since this is a multi-bulk write, but at this stage we don't know
+     * the intersection set size, so we use a trick, append an empty object
+     * to the output list and save the pointer to later modify it with the
+     * right length */
+    if (!dstkey) {
+        lenobj = createObject(REDIS_STRING,NULL);
+        addReply(c,lenobj);
+        decrRefCount(lenobj);
+    } else {
+        /* If we have a target key where to store the resulting set
+         * create this key with an empty set inside */
+        dstset = createSetObject();
+    }
+
+    /* Iterate all the elements of the first (smallest) set, and test
+     * the element against all the other sets, if at least one set does
+     * not include the element it is discarded */
+    di = dictGetIterator(dv[0]);
+
+    while((de = dictNext(di)) != NULL) {
+        robj *ele;
+
+        for (j = 1; j < setsnum; j++)
+            if (dictFind(dv[j],dictGetEntryKey(de)) == NULL) break;
+        if (j != setsnum)
+            continue; /* at least one set does not contain the member */
+        ele = dictGetEntryKey(de);
+        if (!dstkey) {
+            addReplyBulk(c,ele);
+            cardinality++;
+        } else {
+            dictAdd(dstset->ptr,ele,NULL);
+            incrRefCount(ele);
+        }
+    }
+    dictReleaseIterator(di);
+
+    if (dstkey) {
+        /* Store the resulting set into the target, if the intersection
+         * is not an empty set. */
+        dbDelete(c->db,dstkey);
+        if (dictSize((dict*)dstset->ptr) > 0) {
+            dbAdd(c->db,dstkey,dstset);
+            addReplyLongLong(c,dictSize((dict*)dstset->ptr));
+        } else {
+            decrRefCount(dstset);
+            addReply(c,shared.czero);
+        }
+        server.dirty++;
+    } else {
+        lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",cardinality);
+    }
+    zfree(dv);
+}
+
+void sinterCommand(redisClient *c) {
+    sinterGenericCommand(c,c->argv+1,c->argc-1,NULL);
+}
+
+void sinterstoreCommand(redisClient *c) {
+    sinterGenericCommand(c,c->argv+2,c->argc-2,c->argv[1]);
+}
+
+void sunionDiffGenericCommand(redisClient *c, robj **setskeys, int setsnum, robj *dstkey, int op) {
+    dict **dv = zmalloc(sizeof(dict*)*setsnum);
+    dictIterator *di;
+    dictEntry *de;
+    robj *dstset = NULL;
+    int j, cardinality = 0;
+
+    for (j = 0; j < setsnum; j++) {
+        robj *setobj;
+
+        setobj = dstkey ?
+                    lookupKeyWrite(c->db,setskeys[j]) :
+                    lookupKeyRead(c->db,setskeys[j]);
+        if (!setobj) {
+            dv[j] = NULL;
+            continue;
+        }
+        if (setobj->type != REDIS_SET) {
+            zfree(dv);
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+        dv[j] = setobj->ptr;
+    }
+
+    /* We need a temp set object to store our union. If the dstkey
+     * is not NULL (that is, we are inside an SUNIONSTORE operation) then
+     * this set object will be the resulting object to set into the target key*/
+    dstset = createSetObject();
+
+    /* Iterate all the elements of all the sets, add every element a single
+     * time to the result set */
+    for (j = 0; j < setsnum; j++) {
+        if (op == REDIS_OP_DIFF && j == 0 && !dv[j]) break; /* result set is empty */
+        if (!dv[j]) continue; /* non existing keys are like empty sets */
+
+        di = dictGetIterator(dv[j]);
+
+        while((de = dictNext(di)) != NULL) {
+            robj *ele;
+
+            /* dictAdd will not add the same element multiple times */
+            ele = dictGetEntryKey(de);
+            if (op == REDIS_OP_UNION || j == 0) {
+                if (dictAdd(dstset->ptr,ele,NULL) == DICT_OK) {
+                    incrRefCount(ele);
+                    cardinality++;
+                }
+            } else if (op == REDIS_OP_DIFF) {
+                if (dictDelete(dstset->ptr,ele) == DICT_OK) {
+                    cardinality--;
+                }
+            }
+        }
+        dictReleaseIterator(di);
+
+        /* result set is empty? Exit asap. */
+        if (op == REDIS_OP_DIFF && cardinality == 0) break;
+    }
+
+    /* Output the content of the resulting set, if not in STORE mode */
+    if (!dstkey) {
+        addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",cardinality));
+        di = dictGetIterator(dstset->ptr);
+        while((de = dictNext(di)) != NULL) {
+            robj *ele;
+
+            ele = dictGetEntryKey(de);
+            addReplyBulk(c,ele);
+        }
+        dictReleaseIterator(di);
+        decrRefCount(dstset);
+    } else {
+        /* If we have a target key where to store the resulting set
+         * create this key with the result set inside */
+        dbDelete(c->db,dstkey);
+        if (dictSize((dict*)dstset->ptr) > 0) {
+            dbAdd(c->db,dstkey,dstset);
+            addReplyLongLong(c,dictSize((dict*)dstset->ptr));
+        } else {
+            decrRefCount(dstset);
+            addReply(c,shared.czero);
+        }
+        server.dirty++;
+    }
+    zfree(dv);
+}
+
+void sunionCommand(redisClient *c) {
+    sunionDiffGenericCommand(c,c->argv+1,c->argc-1,NULL,REDIS_OP_UNION);
+}
+
+void sunionstoreCommand(redisClient *c) {
+    sunionDiffGenericCommand(c,c->argv+2,c->argc-2,c->argv[1],REDIS_OP_UNION);
+}
+
+void sdiffCommand(redisClient *c) {
+    sunionDiffGenericCommand(c,c->argv+1,c->argc-1,NULL,REDIS_OP_DIFF);
+}
+
+void sdiffstoreCommand(redisClient *c) {
+    sunionDiffGenericCommand(c,c->argv+2,c->argc-2,c->argv[1],REDIS_OP_DIFF);
+}

src/t_string.c

@@ -0,0 +1,251 @@
+#include "redis.h"
+
+/*-----------------------------------------------------------------------------
+ * String Commands
+ *----------------------------------------------------------------------------*/
+
+void setGenericCommand(redisClient *c, int nx, robj *key, robj *val, robj *expire) {
+    int retval;
+    long seconds = 0; /* initialized to avoid an harmness warning */
+
+    if (expire) {
+        if (getLongFromObjectOrReply(c, expire, &seconds, NULL) != REDIS_OK)
+            return;
+        if (seconds <= 0) {
+            addReplySds(c,sdsnew("-ERR invalid expire time in SETEX\r\n"));
+            return;
+        }
+    }
+
+    touchWatchedKey(c->db,key);
+    if (nx) deleteIfVolatile(c->db,key);
+    retval = dbAdd(c->db,key,val);
+    if (retval == REDIS_ERR) {
+        if (!nx) {
+            dbReplace(c->db,key,val);
+            incrRefCount(val);
+        } else {
+            addReply(c,shared.czero);
+            return;
+        }
+    } else {
+        incrRefCount(val);
+    }
+    server.dirty++;
+    removeExpire(c->db,key);
+    if (expire) setExpire(c->db,key,time(NULL)+seconds);
+    addReply(c, nx ? shared.cone : shared.ok);
+}
+
+void setCommand(redisClient *c) {
+    setGenericCommand(c,0,c->argv[1],c->argv[2],NULL);
+}
+
+void setnxCommand(redisClient *c) {
+    setGenericCommand(c,1,c->argv[1],c->argv[2],NULL);
+}
+
+void setexCommand(redisClient *c) {
+    setGenericCommand(c,0,c->argv[1],c->argv[3],c->argv[2]);
+}
+
+int getGenericCommand(redisClient *c) {
+    robj *o;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL)
+        return REDIS_OK;
+
+    if (o->type != REDIS_STRING) {
+        addReply(c,shared.wrongtypeerr);
+        return REDIS_ERR;
+    } else {
+        addReplyBulk(c,o);
+        return REDIS_OK;
+    }
+}
+
+void getCommand(redisClient *c) {
+    getGenericCommand(c);
+}
+
+void getsetCommand(redisClient *c) {
+    if (getGenericCommand(c) == REDIS_ERR) return;
+    dbReplace(c->db,c->argv[1],c->argv[2]);
+    incrRefCount(c->argv[2]);
+    server.dirty++;
+    removeExpire(c->db,c->argv[1]);
+}
+
+void mgetCommand(redisClient *c) {
+    int j;
+
+    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",c->argc-1));
+    for (j = 1; j < c->argc; j++) {
+        robj *o = lookupKeyRead(c->db,c->argv[j]);
+        if (o == NULL) {
+            addReply(c,shared.nullbulk);
+        } else {
+            if (o->type != REDIS_STRING) {
+                addReply(c,shared.nullbulk);
+            } else {
+                addReplyBulk(c,o);
+            }
+        }
+    }
+}
+
+void msetGenericCommand(redisClient *c, int nx) {
+    int j, busykeys = 0;
+
+    if ((c->argc % 2) == 0) {
+        addReplySds(c,sdsnew("-ERR wrong number of arguments for MSET\r\n"));
+        return;
+    }
+    /* Handle the NX flag. The MSETNX semantic is to return zero and don't
+     * set nothing at all if at least one already key exists. */
+    if (nx) {
+        for (j = 1; j < c->argc; j += 2) {
+            if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
+                busykeys++;
+            }
+        }
+    }
+    if (busykeys) {
+        addReply(c, shared.czero);
+        return;
+    }
+
+    for (j = 1; j < c->argc; j += 2) {
+        c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
+        dbReplace(c->db,c->argv[j],c->argv[j+1]);
+        incrRefCount(c->argv[j+1]);
+        removeExpire(c->db,c->argv[j]);
+    }
+    server.dirty += (c->argc-1)/2;
+    addReply(c, nx ? shared.cone : shared.ok);
+}
+
+void msetCommand(redisClient *c) {
+    msetGenericCommand(c,0);
+}
+
+void msetnxCommand(redisClient *c) {
+    msetGenericCommand(c,1);
+}
+
+void incrDecrCommand(redisClient *c, long long incr) {
+    long long value;
+    robj *o;
+
+    o = lookupKeyWrite(c->db,c->argv[1]);
+    if (o != NULL && checkType(c,o,REDIS_STRING)) return;
+    if (getLongLongFromObjectOrReply(c,o,&value,NULL) != REDIS_OK) return;
+
+    value += incr;
+    o = createStringObjectFromLongLong(value);
+    dbReplace(c->db,c->argv[1],o);
+    server.dirty++;
+    addReply(c,shared.colon);
+    addReply(c,o);
+    addReply(c,shared.crlf);
+}
+
+void incrCommand(redisClient *c) {
+    incrDecrCommand(c,1);
+}
+
+void decrCommand(redisClient *c) {
+    incrDecrCommand(c,-1);
+}
+
+void incrbyCommand(redisClient *c) {
+    long long incr;
+
+    if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != REDIS_OK) return;
+    incrDecrCommand(c,incr);
+}
+
+void decrbyCommand(redisClient *c) {
+    long long incr;
+
+    if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != REDIS_OK) return;
+    incrDecrCommand(c,-incr);
+}
+
+void appendCommand(redisClient *c) {
+    int retval;
+    size_t totlen;
+    robj *o;
+
+    o = lookupKeyWrite(c->db,c->argv[1]);
+    if (o == NULL) {
+        /* Create the key */
+        retval = dbAdd(c->db,c->argv[1],c->argv[2]);
+        incrRefCount(c->argv[2]);
+        totlen = stringObjectLen(c->argv[2]);
+    } else {
+        if (o->type != REDIS_STRING) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+        /* If the object is specially encoded or shared we have to make
+         * a copy */
+        if (o->refcount != 1 || o->encoding != REDIS_ENCODING_RAW) {
+            robj *decoded = getDecodedObject(o);
+
+            o = createStringObject(decoded->ptr, sdslen(decoded->ptr));
+            decrRefCount(decoded);
+            dbReplace(c->db,c->argv[1],o);
+        }
+        /* APPEND! */
+        if (c->argv[2]->encoding == REDIS_ENCODING_RAW) {
+            o->ptr = sdscatlen(o->ptr,
+                c->argv[2]->ptr, sdslen(c->argv[2]->ptr));
+        } else {
+            o->ptr = sdscatprintf(o->ptr, "%ld",
+                (unsigned long) c->argv[2]->ptr);
+        }
+        totlen = sdslen(o->ptr);
+    }
+    server.dirty++;
+    addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",(unsigned long)totlen));
+}
+
+void substrCommand(redisClient *c) {
+    robj *o;
+    long start = atoi(c->argv[2]->ptr);
+    long end = atoi(c->argv[3]->ptr);
+    size_t rangelen, strlen;
+    sds range;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,o,REDIS_STRING)) return;
+
+    o = getDecodedObject(o);
+    strlen = sdslen(o->ptr);
+
+    /* convert negative indexes */
+    if (start < 0) start = strlen+start;
+    if (end < 0) end = strlen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+
+    /* indexes sanity checks */
+    if (start > end || (size_t)start >= strlen) {
+        /* Out of range start or start > end result in null reply */
+        addReply(c,shared.nullbulk);
+        decrRefCount(o);
+        return;
+    }
+    if ((size_t)end >= strlen) end = strlen-1;
+    rangelen = (end-start)+1;
+
+    /* Return the result */
+    addReplySds(c,sdscatprintf(sdsempty(),"$%zu\r\n",rangelen));
+    range = sdsnewlen((char*)o->ptr+start,rangelen);
+    addReplySds(c,range);
+    addReply(c,shared.crlf);
+    decrRefCount(o);
+}
+
+

src/t_zset.c

@@ -0,0 +1,985 @@
+#include "redis.h"
+
+#include <math.h>
+
+/*-----------------------------------------------------------------------------
+ * Sorted set API
+ *----------------------------------------------------------------------------*/
+
+/* ZSETs are ordered sets using two data structures to hold the same elements
+ * in order to get O(log(N)) INSERT and REMOVE operations into a sorted
+ * data structure.
+ *
+ * The elements are added to an hash table mapping Redis objects to scores.
+ * At the same time the elements are added to a skip list mapping scores
+ * to Redis objects (so objects are sorted by scores in this "view"). */
+
+/* This skiplist implementation is almost a C translation of the original
+ * algorithm described by William Pugh in "Skip Lists: A Probabilistic
+ * Alternative to Balanced Trees", modified in three ways:
+ * a) this implementation allows for repeated values.
+ * b) the comparison is not just by key (our 'score') but by satellite data.
+ * c) there is a back pointer, so it's a doubly linked list with the back
+ * pointers being only at "level 1". This allows to traverse the list
+ * from tail to head, useful for ZREVRANGE. */
+
+zskiplistNode *zslCreateNode(int level, double score, robj *obj) {
+    zskiplistNode *zn = zmalloc(sizeof(*zn));
+
+    zn->forward = zmalloc(sizeof(zskiplistNode*) * level);
+    if (level > 1)
+        zn->span = zmalloc(sizeof(unsigned int) * (level - 1));
+    else
+        zn->span = NULL;
+    zn->score = score;
+    zn->obj = obj;
+    return zn;
+}
+
+zskiplist *zslCreate(void) {
+    int j;
+    zskiplist *zsl;
+
+    zsl = zmalloc(sizeof(*zsl));
+    zsl->level = 1;
+    zsl->length = 0;
+    zsl->header = zslCreateNode(ZSKIPLIST_MAXLEVEL,0,NULL);
+    for (j = 0; j < ZSKIPLIST_MAXLEVEL; j++) {
+        zsl->header->forward[j] = NULL;
+
+        /* span has space for ZSKIPLIST_MAXLEVEL-1 elements */
+        if (j < ZSKIPLIST_MAXLEVEL-1)
+            zsl->header->span[j] = 0;
+    }
+    zsl->header->backward = NULL;
+    zsl->tail = NULL;
+    return zsl;
+}
+
+void zslFreeNode(zskiplistNode *node) {
+    decrRefCount(node->obj);
+    zfree(node->forward);
+    zfree(node->span);
+    zfree(node);
+}
+
+void zslFree(zskiplist *zsl) {
+    zskiplistNode *node = zsl->header->forward[0], *next;
+
+    zfree(zsl->header->forward);
+    zfree(zsl->header->span);
+    zfree(zsl->header);
+    while(node) {
+        next = node->forward[0];
+        zslFreeNode(node);
+        node = next;
+    }
+    zfree(zsl);
+}
+
+int zslRandomLevel(void) {
+    int level = 1;
+    while ((random()&0xFFFF) < (ZSKIPLIST_P * 0xFFFF))
+        level += 1;
+    return (level<ZSKIPLIST_MAXLEVEL) ? level : ZSKIPLIST_MAXLEVEL;
+}
+
+void zslInsert(zskiplist *zsl, double score, robj *obj) {
+    zskiplistNode *update[ZSKIPLIST_MAXLEVEL], *x;
+    unsigned int rank[ZSKIPLIST_MAXLEVEL];
+    int i, level;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        /* store rank that is crossed to reach the insert position */
+        rank[i] = i == (zsl->level-1) ? 0 : rank[i+1];
+
+        while (x->forward[i] &&
+            (x->forward[i]->score < score ||
+                (x->forward[i]->score == score &&
+                compareStringObjects(x->forward[i]->obj,obj) < 0))) {
+            rank[i] += i > 0 ? x->span[i-1] : 1;
+            x = x->forward[i];
+        }
+        update[i] = x;
+    }
+    /* we assume the key is not already inside, since we allow duplicated
+     * scores, and the re-insertion of score and redis object should never
+     * happpen since the caller of zslInsert() should test in the hash table
+     * if the element is already inside or not. */
+    level = zslRandomLevel();
+    if (level > zsl->level) {
+        for (i = zsl->level; i < level; i++) {
+            rank[i] = 0;
+            update[i] = zsl->header;
+            update[i]->span[i-1] = zsl->length;
+        }
+        zsl->level = level;
+    }
+    x = zslCreateNode(level,score,obj);
+    for (i = 0; i < level; i++) {
+        x->forward[i] = update[i]->forward[i];
+        update[i]->forward[i] = x;
+
+        /* update span covered by update[i] as x is inserted here */
+        if (i > 0) {
+            x->span[i-1] = update[i]->span[i-1] - (rank[0] - rank[i]);
+            update[i]->span[i-1] = (rank[0] - rank[i]) + 1;
+        }
+    }
+
+    /* increment span for untouched levels */
+    for (i = level; i < zsl->level; i++) {
+        update[i]->span[i-1]++;
+    }
+
+    x->backward = (update[0] == zsl->header) ? NULL : update[0];
+    if (x->forward[0])
+        x->forward[0]->backward = x;
+    else
+        zsl->tail = x;
+    zsl->length++;
+}
+
+/* Internal function used by zslDelete, zslDeleteByScore and zslDeleteByRank */
+void zslDeleteNode(zskiplist *zsl, zskiplistNode *x, zskiplistNode **update) {
+    int i;
+    for (i = 0; i < zsl->level; i++) {
+        if (update[i]->forward[i] == x) {
+            if (i > 0) {
+                update[i]->span[i-1] += x->span[i-1] - 1;
+            }
+            update[i]->forward[i] = x->forward[i];
+        } else {
+            /* invariant: i > 0, because update[0]->forward[0]
+             * is always equal to x */
+            update[i]->span[i-1] -= 1;
+        }
+    }
+    if (x->forward[0]) {
+        x->forward[0]->backward = x->backward;
+    } else {
+        zsl->tail = x->backward;
+    }
+    while(zsl->level > 1 && zsl->header->forward[zsl->level-1] == NULL)
+        zsl->level--;
+    zsl->length--;
+}
+
+/* Delete an element with matching score/object from the skiplist. */
+int zslDelete(zskiplist *zsl, double score, robj *obj) {
+    zskiplistNode *update[ZSKIPLIST_MAXLEVEL], *x;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] &&
+            (x->forward[i]->score < score ||
+                (x->forward[i]->score == score &&
+                compareStringObjects(x->forward[i]->obj,obj) < 0)))
+            x = x->forward[i];
+        update[i] = x;
+    }
+    /* We may have multiple elements with the same score, what we need
+     * is to find the element with both the right score and object. */
+    x = x->forward[0];
+    if (x && score == x->score && equalStringObjects(x->obj,obj)) {
+        zslDeleteNode(zsl, x, update);
+        zslFreeNode(x);
+        return 1;
+    } else {
+        return 0; /* not found */
+    }
+    return 0; /* not found */
+}
+
+/* Delete all the elements with score between min and max from the skiplist.
+ * Min and mx are inclusive, so a score >= min || score <= max is deleted.
+ * Note that this function takes the reference to the hash table view of the
+ * sorted set, in order to remove the elements from the hash table too. */
+unsigned long zslDeleteRangeByScore(zskiplist *zsl, double min, double max, dict *dict) {
+    zskiplistNode *update[ZSKIPLIST_MAXLEVEL], *x;
+    unsigned long removed = 0;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] && x->forward[i]->score < min)
+            x = x->forward[i];
+        update[i] = x;
+    }
+    /* We may have multiple elements with the same score, what we need
+     * is to find the element with both the right score and object. */
+    x = x->forward[0];
+    while (x && x->score <= max) {
+        zskiplistNode *next = x->forward[0];
+        zslDeleteNode(zsl, x, update);
+        dictDelete(dict,x->obj);
+        zslFreeNode(x);
+        removed++;
+        x = next;
+    }
+    return removed; /* not found */
+}
+
+/* Delete all the elements with rank between start and end from the skiplist.
+ * Start and end are inclusive. Note that start and end need to be 1-based */
+unsigned long zslDeleteRangeByRank(zskiplist *zsl, unsigned int start, unsigned int end, dict *dict) {
+    zskiplistNode *update[ZSKIPLIST_MAXLEVEL], *x;
+    unsigned long traversed = 0, removed = 0;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] && (traversed + (i > 0 ? x->span[i-1] : 1)) < start) {
+            traversed += i > 0 ? x->span[i-1] : 1;
+            x = x->forward[i];
+        }
+        update[i] = x;
+    }
+
+    traversed++;
+    x = x->forward[0];
+    while (x && traversed <= end) {
+        zskiplistNode *next = x->forward[0];
+        zslDeleteNode(zsl, x, update);
+        dictDelete(dict,x->obj);
+        zslFreeNode(x);
+        removed++;
+        traversed++;
+        x = next;
+    }
+    return removed;
+}
+
+/* Find the first node having a score equal or greater than the specified one.
+ * Returns NULL if there is no match. */
+zskiplistNode *zslFirstWithScore(zskiplist *zsl, double score) {
+    zskiplistNode *x;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] && x->forward[i]->score < score)
+            x = x->forward[i];
+    }
+    /* We may have multiple elements with the same score, what we need
+     * is to find the element with both the right score and object. */
+    return x->forward[0];
+}
+
+/* Find the rank for an element by both score and key.
+ * Returns 0 when the element cannot be found, rank otherwise.
+ * Note that the rank is 1-based due to the span of zsl->header to the
+ * first element. */
+unsigned long zslistTypeGetRank(zskiplist *zsl, double score, robj *o) {
+    zskiplistNode *x;
+    unsigned long rank = 0;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] &&
+            (x->forward[i]->score < score ||
+                (x->forward[i]->score == score &&
+                compareStringObjects(x->forward[i]->obj,o) <= 0))) {
+            rank += i > 0 ? x->span[i-1] : 1;
+            x = x->forward[i];
+        }
+
+        /* x might be equal to zsl->header, so test if obj is non-NULL */
+        if (x->obj && equalStringObjects(x->obj,o)) {
+            return rank;
+        }
+    }
+    return 0;
+}
+
+/* Finds an element by its rank. The rank argument needs to be 1-based. */
+zskiplistNode* zslistTypeGetElementByRank(zskiplist *zsl, unsigned long rank) {
+    zskiplistNode *x;
+    unsigned long traversed = 0;
+    int i;
+
+    x = zsl->header;
+    for (i = zsl->level-1; i >= 0; i--) {
+        while (x->forward[i] && (traversed + (i>0 ? x->span[i-1] : 1)) <= rank)
+        {
+            traversed += i > 0 ? x->span[i-1] : 1;
+            x = x->forward[i];
+        }
+        if (traversed == rank) {
+            return x;
+        }
+    }
+    return NULL;
+}
+
+/*-----------------------------------------------------------------------------
+ * Sorted set commands 
+ *----------------------------------------------------------------------------*/
+
+/* This generic command implements both ZADD and ZINCRBY.
+ * scoreval is the score if the operation is a ZADD (doincrement == 0) or
+ * the increment if the operation is a ZINCRBY (doincrement == 1). */
+void zaddGenericCommand(redisClient *c, robj *key, robj *ele, double scoreval, int doincrement) {
+    robj *zsetobj;
+    zset *zs;
+    double *score;
+
+    if (isnan(scoreval)) {
+        addReplySds(c,sdsnew("-ERR provide score is Not A Number (nan)\r\n"));
+        return;
+    }
+
+    zsetobj = lookupKeyWrite(c->db,key);
+    if (zsetobj == NULL) {
+        zsetobj = createZsetObject();
+        dbAdd(c->db,key,zsetobj);
+    } else {
+        if (zsetobj->type != REDIS_ZSET) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+    }
+    zs = zsetobj->ptr;
+
+    /* Ok now since we implement both ZADD and ZINCRBY here the code
+     * needs to handle the two different conditions. It's all about setting
+     * '*score', that is, the new score to set, to the right value. */
+    score = zmalloc(sizeof(double));
+    if (doincrement) {
+        dictEntry *de;
+
+        /* Read the old score. If the element was not present starts from 0 */
+        de = dictFind(zs->dict,ele);
+        if (de) {
+            double *oldscore = dictGetEntryVal(de);
+            *score = *oldscore + scoreval;
+        } else {
+            *score = scoreval;
+        }
+        if (isnan(*score)) {
+            addReplySds(c,
+                sdsnew("-ERR resulting score is Not A Number (nan)\r\n"));
+            zfree(score);
+            /* Note that we don't need to check if the zset may be empty and
+             * should be removed here, as we can only obtain Nan as score if
+             * there was already an element in the sorted set. */
+            return;
+        }
+    } else {
+        *score = scoreval;
+    }
+
+    /* What follows is a simple remove and re-insert operation that is common
+     * to both ZADD and ZINCRBY... */
+    if (dictAdd(zs->dict,ele,score) == DICT_OK) {
+        /* case 1: New element */
+        incrRefCount(ele); /* added to hash */
+        zslInsert(zs->zsl,*score,ele);
+        incrRefCount(ele); /* added to skiplist */
+        server.dirty++;
+        if (doincrement)
+            addReplyDouble(c,*score);
+        else
+            addReply(c,shared.cone);
+    } else {
+        dictEntry *de;
+        double *oldscore;
+
+        /* case 2: Score update operation */
+        de = dictFind(zs->dict,ele);
+        redisAssert(de != NULL);
+        oldscore = dictGetEntryVal(de);
+        if (*score != *oldscore) {
+            int deleted;
+
+            /* Remove and insert the element in the skip list with new score */
+            deleted = zslDelete(zs->zsl,*oldscore,ele);
+            redisAssert(deleted != 0);
+            zslInsert(zs->zsl,*score,ele);
+            incrRefCount(ele);
+            /* Update the score in the hash table */
+            dictReplace(zs->dict,ele,score);
+            server.dirty++;
+        } else {
+            zfree(score);
+        }
+        if (doincrement)
+            addReplyDouble(c,*score);
+        else
+            addReply(c,shared.czero);
+    }
+}
+
+void zaddCommand(redisClient *c) {
+    double scoreval;
+
+    if (getDoubleFromObjectOrReply(c, c->argv[2], &scoreval, NULL) != REDIS_OK) return;
+    zaddGenericCommand(c,c->argv[1],c->argv[3],scoreval,0);
+}
+
+void zincrbyCommand(redisClient *c) {
+    double scoreval;
+
+    if (getDoubleFromObjectOrReply(c, c->argv[2], &scoreval, NULL) != REDIS_OK) return;
+    zaddGenericCommand(c,c->argv[1],c->argv[3],scoreval,1);
+}
+
+void zremCommand(redisClient *c) {
+    robj *zsetobj;
+    zset *zs;
+    dictEntry *de;
+    double *oldscore;
+    int deleted;
+
+    if ((zsetobj = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,zsetobj,REDIS_ZSET)) return;
+
+    zs = zsetobj->ptr;
+    de = dictFind(zs->dict,c->argv[2]);
+    if (de == NULL) {
+        addReply(c,shared.czero);
+        return;
+    }
+    /* Delete from the skiplist */
+    oldscore = dictGetEntryVal(de);
+    deleted = zslDelete(zs->zsl,*oldscore,c->argv[2]);
+    redisAssert(deleted != 0);
+
+    /* Delete from the hash table */
+    dictDelete(zs->dict,c->argv[2]);
+    if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) dbDelete(c->db,c->argv[1]);
+    server.dirty++;
+    addReply(c,shared.cone);
+}
+
+void zremrangebyscoreCommand(redisClient *c) {
+    double min;
+    double max;
+    long deleted;
+    robj *zsetobj;
+    zset *zs;
+
+    if ((getDoubleFromObjectOrReply(c, c->argv[2], &min, NULL) != REDIS_OK) ||
+        (getDoubleFromObjectOrReply(c, c->argv[3], &max, NULL) != REDIS_OK)) return;
+
+    if ((zsetobj = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,zsetobj,REDIS_ZSET)) return;
+
+    zs = zsetobj->ptr;
+    deleted = zslDeleteRangeByScore(zs->zsl,min,max,zs->dict);
+    if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) dbDelete(c->db,c->argv[1]);
+    server.dirty += deleted;
+    addReplyLongLong(c,deleted);
+}
+
+void zremrangebyrankCommand(redisClient *c) {
+    long start;
+    long end;
+    int llen;
+    long deleted;
+    robj *zsetobj;
+    zset *zs;
+
+    if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != REDIS_OK) ||
+        (getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != REDIS_OK)) return;
+
+    if ((zsetobj = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,zsetobj,REDIS_ZSET)) return;
+    zs = zsetobj->ptr;
+    llen = zs->zsl->length;
+
+    /* convert negative indexes */
+    if (start < 0) start = llen+start;
+    if (end < 0) end = llen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+
+    /* indexes sanity checks */
+    if (start > end || start >= llen) {
+        addReply(c,shared.czero);
+        return;
+    }
+    if (end >= llen) end = llen-1;
+
+    /* increment start and end because zsl*Rank functions
+     * use 1-based rank */
+    deleted = zslDeleteRangeByRank(zs->zsl,start+1,end+1,zs->dict);
+    if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) dbDelete(c->db,c->argv[1]);
+    server.dirty += deleted;
+    addReplyLongLong(c, deleted);
+}
+
+typedef struct {
+    dict *dict;
+    double weight;
+} zsetopsrc;
+
+int qsortCompareZsetopsrcByCardinality(const void *s1, const void *s2) {
+    zsetopsrc *d1 = (void*) s1, *d2 = (void*) s2;
+    unsigned long size1, size2;
+    size1 = d1->dict ? dictSize(d1->dict) : 0;
+    size2 = d2->dict ? dictSize(d2->dict) : 0;
+    return size1 - size2;
+}
+
+#define REDIS_AGGR_SUM 1
+#define REDIS_AGGR_MIN 2
+#define REDIS_AGGR_MAX 3
+#define zunionInterDictValue(_e) (dictGetEntryVal(_e) == NULL ? 1.0 : *(double*)dictGetEntryVal(_e))
+
+inline static void zunionInterAggregate(double *target, double val, int aggregate) {
+    if (aggregate == REDIS_AGGR_SUM) {
+        *target = *target + val;
+    } else if (aggregate == REDIS_AGGR_MIN) {
+        *target = val < *target ? val : *target;
+    } else if (aggregate == REDIS_AGGR_MAX) {
+        *target = val > *target ? val : *target;
+    } else {
+        /* safety net */
+        redisPanic("Unknown ZUNION/INTER aggregate type");
+    }
+}
+
+void zunionInterGenericCommand(redisClient *c, robj *dstkey, int op) {
+    int i, j, setnum;
+    int aggregate = REDIS_AGGR_SUM;
+    zsetopsrc *src;
+    robj *dstobj;
+    zset *dstzset;
+    dictIterator *di;
+    dictEntry *de;
+
+    /* expect setnum input keys to be given */
+    setnum = atoi(c->argv[2]->ptr);
+    if (setnum < 1) {
+        addReplySds(c,sdsnew("-ERR at least 1 input key is needed for ZUNIONSTORE/ZINTERSTORE\r\n"));
+        return;
+    }
+
+    /* test if the expected number of keys would overflow */
+    if (3+setnum > c->argc) {
+        addReply(c,shared.syntaxerr);
+        return;
+    }
+
+    /* read keys to be used for input */
+    src = zmalloc(sizeof(zsetopsrc) * setnum);
+    for (i = 0, j = 3; i < setnum; i++, j++) {
+        robj *obj = lookupKeyWrite(c->db,c->argv[j]);
+        if (!obj) {
+            src[i].dict = NULL;
+        } else {
+            if (obj->type == REDIS_ZSET) {
+                src[i].dict = ((zset*)obj->ptr)->dict;
+            } else if (obj->type == REDIS_SET) {
+                src[i].dict = (obj->ptr);
+            } else {
+                zfree(src);
+                addReply(c,shared.wrongtypeerr);
+                return;
+            }
+        }
+
+        /* default all weights to 1 */
+        src[i].weight = 1.0;
+    }
+
+    /* parse optional extra arguments */
+    if (j < c->argc) {
+        int remaining = c->argc - j;
+
+        while (remaining) {
+            if (remaining >= (setnum + 1) && !strcasecmp(c->argv[j]->ptr,"weights")) {
+                j++; remaining--;
+                for (i = 0; i < setnum; i++, j++, remaining--) {
+                    if (getDoubleFromObjectOrReply(c, c->argv[j], &src[i].weight, NULL) != REDIS_OK)
+                        return;
+                }
+            } else if (remaining >= 2 && !strcasecmp(c->argv[j]->ptr,"aggregate")) {
+                j++; remaining--;
+                if (!strcasecmp(c->argv[j]->ptr,"sum")) {
+                    aggregate = REDIS_AGGR_SUM;
+                } else if (!strcasecmp(c->argv[j]->ptr,"min")) {
+                    aggregate = REDIS_AGGR_MIN;
+                } else if (!strcasecmp(c->argv[j]->ptr,"max")) {
+                    aggregate = REDIS_AGGR_MAX;
+                } else {
+                    zfree(src);
+                    addReply(c,shared.syntaxerr);
+                    return;
+                }
+                j++; remaining--;
+            } else {
+                zfree(src);
+                addReply(c,shared.syntaxerr);
+                return;
+            }
+        }
+    }
+
+    /* sort sets from the smallest to largest, this will improve our
+     * algorithm's performance */
+    qsort(src,setnum,sizeof(zsetopsrc),qsortCompareZsetopsrcByCardinality);
+
+    dstobj = createZsetObject();
+    dstzset = dstobj->ptr;
+
+    if (op == REDIS_OP_INTER) {
+        /* skip going over all entries if the smallest zset is NULL or empty */
+        if (src[0].dict && dictSize(src[0].dict) > 0) {
+            /* precondition: as src[0].dict is non-empty and the zsets are ordered
+             * from small to large, all src[i > 0].dict are non-empty too */
+            di = dictGetIterator(src[0].dict);
+            while((de = dictNext(di)) != NULL) {
+                double *score = zmalloc(sizeof(double)), value;
+                *score = src[0].weight * zunionInterDictValue(de);
+
+                for (j = 1; j < setnum; j++) {
+                    dictEntry *other = dictFind(src[j].dict,dictGetEntryKey(de));
+                    if (other) {
+                        value = src[j].weight * zunionInterDictValue(other);
+                        zunionInterAggregate(score, value, aggregate);
+                    } else {
+                        break;
+                    }
+                }
+
+                /* skip entry when not present in every source dict */
+                if (j != setnum) {
+                    zfree(score);
+                } else {
+                    robj *o = dictGetEntryKey(de);
+                    dictAdd(dstzset->dict,o,score);
+                    incrRefCount(o); /* added to dictionary */
+                    zslInsert(dstzset->zsl,*score,o);
+                    incrRefCount(o); /* added to skiplist */
+                }
+            }
+            dictReleaseIterator(di);
+        }
+    } else if (op == REDIS_OP_UNION) {
+        for (i = 0; i < setnum; i++) {
+            if (!src[i].dict) continue;
+
+            di = dictGetIterator(src[i].dict);
+            while((de = dictNext(di)) != NULL) {
+                /* skip key when already processed */
+                if (dictFind(dstzset->dict,dictGetEntryKey(de)) != NULL) continue;
+
+                double *score = zmalloc(sizeof(double)), value;
+                *score = src[i].weight * zunionInterDictValue(de);
+
+                /* because the zsets are sorted by size, its only possible
+                 * for sets at larger indices to hold this entry */
+                for (j = (i+1); j < setnum; j++) {
+                    dictEntry *other = dictFind(src[j].dict,dictGetEntryKey(de));
+                    if (other) {
+                        value = src[j].weight * zunionInterDictValue(other);
+                        zunionInterAggregate(score, value, aggregate);
+                    }
+                }
+
+                robj *o = dictGetEntryKey(de);
+                dictAdd(dstzset->dict,o,score);
+                incrRefCount(o); /* added to dictionary */
+                zslInsert(dstzset->zsl,*score,o);
+                incrRefCount(o); /* added to skiplist */
+            }
+            dictReleaseIterator(di);
+        }
+    } else {
+        /* unknown operator */
+        redisAssert(op == REDIS_OP_INTER || op == REDIS_OP_UNION);
+    }
+
+    dbDelete(c->db,dstkey);
+    if (dstzset->zsl->length) {
+        dbAdd(c->db,dstkey,dstobj);
+        addReplyLongLong(c, dstzset->zsl->length);
+        server.dirty++;
+    } else {
+        decrRefCount(dstobj);
+        addReply(c, shared.czero);
+    }
+    zfree(src);
+}
+
+void zunionstoreCommand(redisClient *c) {
+    zunionInterGenericCommand(c,c->argv[1], REDIS_OP_UNION);
+}
+
+void zinterstoreCommand(redisClient *c) {
+    zunionInterGenericCommand(c,c->argv[1], REDIS_OP_INTER);
+}
+
+void zrangeGenericCommand(redisClient *c, int reverse) {
+    robj *o;
+    long start;
+    long end;
+    int withscores = 0;
+    int llen;
+    int rangelen, j;
+    zset *zsetobj;
+    zskiplist *zsl;
+    zskiplistNode *ln;
+    robj *ele;
+
+    if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != REDIS_OK) ||
+        (getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != REDIS_OK)) return;
+
+    if (c->argc == 5 && !strcasecmp(c->argv[4]->ptr,"withscores")) {
+        withscores = 1;
+    } else if (c->argc >= 5) {
+        addReply(c,shared.syntaxerr);
+        return;
+    }
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
+         || checkType(c,o,REDIS_ZSET)) return;
+    zsetobj = o->ptr;
+    zsl = zsetobj->zsl;
+    llen = zsl->length;
+
+    /* convert negative indexes */
+    if (start < 0) start = llen+start;
+    if (end < 0) end = llen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+
+    /* indexes sanity checks */
+    if (start > end || start >= llen) {
+        /* Out of range start or start > end result in empty list */
+        addReply(c,shared.emptymultibulk);
+        return;
+    }
+    if (end >= llen) end = llen-1;
+    rangelen = (end-start)+1;
+
+    /* check if starting point is trivial, before searching
+     * the element in log(N) time */
+    if (reverse) {
+        ln = start == 0 ? zsl->tail : zslistTypeGetElementByRank(zsl, llen-start);
+    } else {
+        ln = start == 0 ?
+            zsl->header->forward[0] : zslistTypeGetElementByRank(zsl, start+1);
+    }
+
+    /* Return the result in form of a multi-bulk reply */
+    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",
+        withscores ? (rangelen*2) : rangelen));
+    for (j = 0; j < rangelen; j++) {
+        ele = ln->obj;
+        addReplyBulk(c,ele);
+        if (withscores)
+            addReplyDouble(c,ln->score);
+        ln = reverse ? ln->backward : ln->forward[0];
+    }
+}
+
+void zrangeCommand(redisClient *c) {
+    zrangeGenericCommand(c,0);
+}
+
+void zrevrangeCommand(redisClient *c) {
+    zrangeGenericCommand(c,1);
+}
+
+/* This command implements both ZRANGEBYSCORE and ZCOUNT.
+ * If justcount is non-zero, just the count is returned. */
+void genericZrangebyscoreCommand(redisClient *c, int justcount) {
+    robj *o;
+    double min, max;
+    int minex = 0, maxex = 0; /* are min or max exclusive? */
+    int offset = 0, limit = -1;
+    int withscores = 0;
+    int badsyntax = 0;
+
+    /* Parse the min-max interval. If one of the values is prefixed
+     * by the "(" character, it's considered "open". For instance
+     * ZRANGEBYSCORE zset (1.5 (2.5 will match min < x < max
+     * ZRANGEBYSCORE zset 1.5 2.5 will instead match min <= x <= max */
+    if (((char*)c->argv[2]->ptr)[0] == '(') {
+        min = strtod((char*)c->argv[2]->ptr+1,NULL);
+        minex = 1;
+    } else {
+        min = strtod(c->argv[2]->ptr,NULL);
+    }
+    if (((char*)c->argv[3]->ptr)[0] == '(') {
+        max = strtod((char*)c->argv[3]->ptr+1,NULL);
+        maxex = 1;
+    } else {
+        max = strtod(c->argv[3]->ptr,NULL);
+    }
+
+    /* Parse "WITHSCORES": note that if the command was called with
+     * the name ZCOUNT then we are sure that c->argc == 4, so we'll never
+     * enter the following paths to parse WITHSCORES and LIMIT. */
+    if (c->argc == 5 || c->argc == 8) {
+        if (strcasecmp(c->argv[c->argc-1]->ptr,"withscores") == 0)
+            withscores = 1;
+        else
+            badsyntax = 1;
+    }
+    if (c->argc != (4 + withscores) && c->argc != (7 + withscores))
+        badsyntax = 1;
+    if (badsyntax) {
+        addReplySds(c,
+            sdsnew("-ERR wrong number of arguments for ZRANGEBYSCORE\r\n"));
+        return;
+    }
+
+    /* Parse "LIMIT" */
+    if (c->argc == (7 + withscores) && strcasecmp(c->argv[4]->ptr,"limit")) {
+        addReply(c,shared.syntaxerr);
+        return;
+    } else if (c->argc == (7 + withscores)) {
+        offset = atoi(c->argv[5]->ptr);
+        limit = atoi(c->argv[6]->ptr);
+        if (offset < 0) offset = 0;
+    }
+
+    /* Ok, lookup the key and get the range */
+    o = lookupKeyRead(c->db,c->argv[1]);
+    if (o == NULL) {
+        addReply(c,justcount ? shared.czero : shared.emptymultibulk);
+    } else {
+        if (o->type != REDIS_ZSET) {
+            addReply(c,shared.wrongtypeerr);
+        } else {
+            zset *zsetobj = o->ptr;
+            zskiplist *zsl = zsetobj->zsl;
+            zskiplistNode *ln;
+            robj *ele, *lenobj = NULL;
+            unsigned long rangelen = 0;
+
+            /* Get the first node with the score >= min, or with
+             * score > min if 'minex' is true. */
+            ln = zslFirstWithScore(zsl,min);
+            while (minex && ln && ln->score == min) ln = ln->forward[0];
+
+            if (ln == NULL) {
+                /* No element matching the speciifed interval */
+                addReply(c,justcount ? shared.czero : shared.emptymultibulk);
+                return;
+            }
+
+            /* We don't know in advance how many matching elements there
+             * are in the list, so we push this object that will represent
+             * the multi-bulk length in the output buffer, and will "fix"
+             * it later */
+            if (!justcount) {
+                lenobj = createObject(REDIS_STRING,NULL);
+                addReply(c,lenobj);
+                decrRefCount(lenobj);
+            }
+
+            while(ln && (maxex ? (ln->score < max) : (ln->score <= max))) {
+                if (offset) {
+                    offset--;
+                    ln = ln->forward[0];
+                    continue;
+                }
+                if (limit == 0) break;
+                if (!justcount) {
+                    ele = ln->obj;
+                    addReplyBulk(c,ele);
+                    if (withscores)
+                        addReplyDouble(c,ln->score);
+                }
+                ln = ln->forward[0];
+                rangelen++;
+                if (limit > 0) limit--;
+            }
+            if (justcount) {
+                addReplyLongLong(c,(long)rangelen);
+            } else {
+                lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",
+                     withscores ? (rangelen*2) : rangelen);
+            }
+        }
+    }
+}
+
+void zrangebyscoreCommand(redisClient *c) {
+    genericZrangebyscoreCommand(c,0);
+}
+
+void zcountCommand(redisClient *c) {
+    genericZrangebyscoreCommand(c,1);
+}
+
+void zcardCommand(redisClient *c) {
+    robj *o;
+    zset *zs;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
+        checkType(c,o,REDIS_ZSET)) return;
+
+    zs = o->ptr;
+    addReplyUlong(c,zs->zsl->length);
+}
+
+void zscoreCommand(redisClient *c) {
+    robj *o;
+    zset *zs;
+    dictEntry *de;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,o,REDIS_ZSET)) return;
+
+    zs = o->ptr;
+    de = dictFind(zs->dict,c->argv[2]);
+    if (!de) {
+        addReply(c,shared.nullbulk);
+    } else {
+        double *score = dictGetEntryVal(de);
+
+        addReplyDouble(c,*score);
+    }
+}
+
+void zrankGenericCommand(redisClient *c, int reverse) {
+    robj *o;
+    zset *zs;
+    zskiplist *zsl;
+    dictEntry *de;
+    unsigned long rank;
+    double *score;
+
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
+        checkType(c,o,REDIS_ZSET)) return;
+
+    zs = o->ptr;
+    zsl = zs->zsl;
+    de = dictFind(zs->dict,c->argv[2]);
+    if (!de) {
+        addReply(c,shared.nullbulk);
+        return;
+    }
+
+    score = dictGetEntryVal(de);
+    rank = zslistTypeGetRank(zsl, *score, c->argv[2]);
+    if (rank) {
+        if (reverse) {
+            addReplyLongLong(c, zsl->length - rank);
+        } else {
+            addReplyLongLong(c, rank-1);
+        }
+    } else {
+        addReply(c,shared.nullbulk);
+    }
+}
+
+void zrankCommand(redisClient *c) {
+    zrankGenericCommand(c, 0);
+}
+
+void zrevrankCommand(redisClient *c) {
+    zrankGenericCommand(c, 1);
+}

src/util.c

@@ -0,0 +1,223 @@
+#include "redis.h"
+#include <ctype.h>
+#include <limits.h>
+
+/* Glob-style pattern matching. */
+int stringmatchlen(const char *pattern, int patternLen,
+        const char *string, int stringLen, int nocase)
+{
+    while(patternLen) {
+        switch(pattern[0]) {
+        case '*':
+            while (pattern[1] == '*') {
+                pattern++;
+                patternLen--;
+            }
+            if (patternLen == 1)
+                return 1; /* match */
+            while(stringLen) {
+                if (stringmatchlen(pattern+1, patternLen-1,
+                            string, stringLen, nocase))
+                    return 1; /* match */
+                string++;
+                stringLen--;
+            }
+            return 0; /* no match */
+            break;
+        case '?':
+            if (stringLen == 0)
+                return 0; /* no match */
+            string++;
+            stringLen--;
+            break;
+        case '[':
+        {
+            int not, match;
+
+            pattern++;
+            patternLen--;
+            not = pattern[0] == '^';
+            if (not) {
+                pattern++;
+                patternLen--;
+            }
+            match = 0;
+            while(1) {
+                if (pattern[0] == '\\') {
+                    pattern++;
+                    patternLen--;
+                    if (pattern[0] == string[0])
+                        match = 1;
+                } else if (pattern[0] == ']') {
+                    break;
+                } else if (patternLen == 0) {
+                    pattern--;
+                    patternLen++;
+                    break;
+                } else if (pattern[1] == '-' && patternLen >= 3) {
+                    int start = pattern[0];
+                    int end = pattern[2];
+                    int c = string[0];
+                    if (start > end) {
+                        int t = start;
+                        start = end;
+                        end = t;
+                    }
+                    if (nocase) {
+                        start = tolower(start);
+                        end = tolower(end);
+                        c = tolower(c);
+                    }
+                    pattern += 2;
+                    patternLen -= 2;
+                    if (c >= start && c <= end)
+                        match = 1;
+                } else {
+                    if (!nocase) {
+                        if (pattern[0] == string[0])
+                            match = 1;
+                    } else {
+                        if (tolower((int)pattern[0]) == tolower((int)string[0]))
+                            match = 1;
+                    }
+                }
+                pattern++;
+                patternLen--;
+            }
+            if (not)
+                match = !match;
+            if (!match)
+                return 0; /* no match */
+            string++;
+            stringLen--;
+            break;
+        }
+        case '\\':
+            if (patternLen >= 2) {
+                pattern++;
+                patternLen--;
+            }
+            /* fall through */
+        default:
+            if (!nocase) {
+                if (pattern[0] != string[0])
+                    return 0; /* no match */
+            } else {
+                if (tolower((int)pattern[0]) != tolower((int)string[0]))
+                    return 0; /* no match */
+            }
+            string++;
+            stringLen--;
+            break;
+        }
+        pattern++;
+        patternLen--;
+        if (stringLen == 0) {
+            while(*pattern == '*') {
+                pattern++;
+                patternLen--;
+            }
+            break;
+        }
+    }
+    if (patternLen == 0 && stringLen == 0)
+        return 1;
+    return 0;
+}
+
+int stringmatch(const char *pattern, const char *string, int nocase) {
+    return stringmatchlen(pattern,strlen(pattern),string,strlen(string),nocase);
+}
+
+/* Convert a string representing an amount of memory into the number of
+ * bytes, so for instance memtoll("1Gi") will return 1073741824 that is
+ * (1024*1024*1024).
+ *
+ * On parsing error, if *err is not NULL, it's set to 1, otherwise it's
+ * set to 0 */
+long long memtoll(const char *p, int *err) {
+    const char *u;
+    char buf[128];
+    long mul; /* unit multiplier */
+    long long val;
+    unsigned int digits;
+
+    if (err) *err = 0;
+    /* Search the first non digit character. */
+    u = p;
+    if (*u == '-') u++;
+    while(*u && isdigit(*u)) u++;
+    if (*u == '\0' || !strcasecmp(u,"b")) {
+        mul = 1;
+    } else if (!strcasecmp(u,"k")) {
+        mul = 1000;
+    } else if (!strcasecmp(u,"kb")) {
+        mul = 1024;
+    } else if (!strcasecmp(u,"m")) {
+        mul = 1000*1000;
+    } else if (!strcasecmp(u,"mb")) {
+        mul = 1024*1024;
+    } else if (!strcasecmp(u,"g")) {
+        mul = 1000L*1000*1000;
+    } else if (!strcasecmp(u,"gb")) {
+        mul = 1024L*1024*1024;
+    } else {
+        if (err) *err = 1;
+        mul = 1;
+    }
+    digits = u-p;
+    if (digits >= sizeof(buf)) {
+        if (err) *err = 1;
+        return LLONG_MAX;
+    }
+    memcpy(buf,p,digits);
+    buf[digits] = '\0';
+    val = strtoll(buf,NULL,10);
+    return val*mul;
+}
+
+/* Convert a long long into a string. Returns the number of
+ * characters needed to represent the number, that can be shorter if passed
+ * buffer length is not enough to store the whole number. */
+int ll2string(char *s, size_t len, long long value) {
+    char buf[32], *p;
+    unsigned long long v;
+    size_t l;
+
+    if (len == 0) return 0;
+    v = (value < 0) ? -value : value;
+    p = buf+31; /* point to the last character */
+    do {
+        *p-- = '0'+(v%10);
+        v /= 10;
+    } while(v);
+    if (value < 0) *p-- = '-';
+    p++;
+    l = 32-(p-buf);
+    if (l+1 > len) l = len-1; /* Make sure it fits, including the nul term */
+    memcpy(s,p,l);
+    s[l] = '\0';
+    return l;
+}
+
+/* Check if the nul-terminated string 's' can be represented by a long
+ * (that is, is a number that fits into long without any other space or
+ * character before or after the digits).
+ *
+ * If so, the function returns REDIS_OK and *longval is set to the value
+ * of the number. Otherwise REDIS_ERR is returned */
+int isStringRepresentableAsLong(sds s, long *longval) {
+    char buf[32], *endptr;
+    long value;
+    int slen;
+
+    value = strtol(s, &endptr, 10);
+    if (endptr[0] != '\0') return REDIS_ERR;
+    slen = ll2string(buf,32,value);
+
+    /* If the number converted back into a string is not identical
+     * then it's not possible to encode the string as integer */
+    if (sdslen(s) != (unsigned)slen || memcmp(buf,s,slen)) return REDIS_ERR;
+    if (longval) *longval = value;
+    return REDIS_OK;
+}

src/version.h

@@ -0,0 +1 @@
+#define REDIS_VERSION "2.1.1"

staticsymbols.h

@@ -1,374 +0,0 @@
-static struct redisFunctionSym symsTable[] = {
-{"IOThreadEntryPoint",(unsigned long)IOThreadEntryPoint},
-{"_redisAssert",(unsigned long)_redisAssert},
-{"_redisPanic",(unsigned long)_redisPanic},
-{"acceptHandler",(unsigned long)acceptHandler},
-{"addReply",(unsigned long)addReply},
-{"addReplyBulk",(unsigned long)addReplyBulk},
-{"addReplyBulkCString",(unsigned long)addReplyBulkCString},
-{"addReplyBulkLen",(unsigned long)addReplyBulkLen},
-{"addReplyBulkSds",(unsigned long)addReplyBulkSds},
-{"addReplyDouble",(unsigned long)addReplyDouble},
-{"addReplyLongLong",(unsigned long)addReplyLongLong},
-{"addReplySds",(unsigned long)addReplySds},
-{"addReplyUlong",(unsigned long)addReplyUlong},
-{"aofRemoveTempFile",(unsigned long)aofRemoveTempFile},
-{"appendCommand",(unsigned long)appendCommand},
-{"appendServerSaveParams",(unsigned long)appendServerSaveParams},
-{"authCommand",(unsigned long)authCommand},
-{"beforeSleep",(unsigned long)beforeSleep},
-{"bgrewriteaofCommand",(unsigned long)bgrewriteaofCommand},
-{"bgsaveCommand",(unsigned long)bgsaveCommand},
-{"blockClientOnSwappedKeys",(unsigned long)blockClientOnSwappedKeys},
-{"blockForKeys",(unsigned long)blockForKeys},
-{"blockingPopGenericCommand",(unsigned long)blockingPopGenericCommand},
-{"blpopCommand",(unsigned long)blpopCommand},
-{"brpopCommand",(unsigned long)brpopCommand},
-{"bytesToHuman",(unsigned long)bytesToHuman},
-{"call",(unsigned long)call},
-{"catAppendOnlyExpireAtCommand",(unsigned long)catAppendOnlyExpireAtCommand},
-{"catAppendOnlyGenericCommand",(unsigned long)catAppendOnlyGenericCommand},
-{"checkType",(unsigned long)checkType},
-{"closeTimedoutClients",(unsigned long)closeTimedoutClients},
-{"compareStringObjects",(unsigned long)compareStringObjects},
-{"computeDatasetDigest",(unsigned long)computeDatasetDigest},
-{"computeObjectSwappability",(unsigned long)computeObjectSwappability},
-{"configCommand",(unsigned long)configCommand},
-{"configGetCommand",(unsigned long)configGetCommand},
-{"configSetCommand",(unsigned long)configSetCommand},
-{"convertToRealHash",(unsigned long)convertToRealHash},
-{"createClient",(unsigned long)createClient},
-{"createHashObject",(unsigned long)createHashObject},
-{"createListObject",(unsigned long)createListObject},
-{"createObject",(unsigned long)createObject},
-{"createSetObject",(unsigned long)createSetObject},
-{"createSharedObjects",(unsigned long)createSharedObjects},
-{"createSortOperation",(unsigned long)createSortOperation},
-{"createStringObject",(unsigned long)createStringObject},
-{"createStringObjectFromLongLong",(unsigned long)createStringObjectFromLongLong},
-{"createVmPointer",(unsigned long)createVmPointer},
-{"createZsetObject",(unsigned long)createZsetObject},
-{"daemonize",(unsigned long)daemonize},
-{"dbAdd",(unsigned long)dbAdd},
-{"dbDelete",(unsigned long)dbDelete},
-{"dbExists",(unsigned long)dbExists},
-{"dbRandomKey",(unsigned long)dbRandomKey},
-{"dbReplace",(unsigned long)dbReplace},
-{"dbsizeCommand",(unsigned long)dbsizeCommand},
-{"debugCommand",(unsigned long)debugCommand},
-{"decrCommand",(unsigned long)decrCommand},
-{"decrRefCount",(unsigned long)decrRefCount},
-{"decrbyCommand",(unsigned long)decrbyCommand},
-{"delCommand",(unsigned long)delCommand},
-{"deleteIfVolatile",(unsigned long)deleteIfVolatile},
-{"dictEncObjKeyCompare",(unsigned long)dictEncObjKeyCompare},
-{"dictListDestructor",(unsigned long)dictListDestructor},
-{"dictObjKeyCompare",(unsigned long)dictObjKeyCompare},
-{"dictRedisObjectDestructor",(unsigned long)dictRedisObjectDestructor},
-{"dictSdsDestructor",(unsigned long)dictSdsDestructor},
-{"dictSdsKeyCompare",(unsigned long)dictSdsKeyCompare},
-{"dictVanillaFree",(unsigned long)dictVanillaFree},
-{"discardCommand",(unsigned long)discardCommand},
-{"dontWaitForSwappedKey",(unsigned long)dontWaitForSwappedKey},
-{"dupClientReplyValue",(unsigned long)dupClientReplyValue},
-{"dupStringObject",(unsigned long)dupStringObject},
-{"echoCommand",(unsigned long)echoCommand},
-{"equalStringObjects",(unsigned long)equalStringObjects},
-{"execBlockClientOnSwappedKeys",(unsigned long)execBlockClientOnSwappedKeys},
-{"execCommand",(unsigned long)execCommand},
-{"execCommandReplicateMulti",(unsigned long)execCommandReplicateMulti},
-{"existsCommand",(unsigned long)existsCommand},
-{"expireCommand",(unsigned long)expireCommand},
-{"expireGenericCommand",(unsigned long)expireGenericCommand},
-{"expireIfNeeded",(unsigned long)expireIfNeeded},
-{"expireatCommand",(unsigned long)expireatCommand},
-{"feedAppendOnlyFile",(unsigned long)feedAppendOnlyFile},
-{"findFuncName",(unsigned long)findFuncName},
-{"flushAppendOnlyFile",(unsigned long)flushAppendOnlyFile},
-{"flushallCommand",(unsigned long)flushallCommand},
-{"flushdbCommand",(unsigned long)flushdbCommand},
-{"freeClient",(unsigned long)freeClient},
-{"freeClientArgv",(unsigned long)freeClientArgv},
-{"freeClientMultiState",(unsigned long)freeClientMultiState},
-{"freeFakeClient",(unsigned long)freeFakeClient},
-{"freeHashObject",(unsigned long)freeHashObject},
-{"freeIOJob",(unsigned long)freeIOJob},
-{"freeListObject",(unsigned long)freeListObject},
-{"freeMemoryIfNeeded",(unsigned long)freeMemoryIfNeeded},
-{"freePubsubPattern",(unsigned long)freePubsubPattern},
-{"freeSetObject",(unsigned long)freeSetObject},
-{"freeStringObject",(unsigned long)freeStringObject},
-{"freeZsetObject",(unsigned long)freeZsetObject},
-{"fwriteBulkDouble",(unsigned long)fwriteBulkDouble},
-{"fwriteBulkLongLong",(unsigned long)fwriteBulkLongLong},
-{"fwriteBulkObject",(unsigned long)fwriteBulkObject},
-{"fwriteBulkString",(unsigned long)fwriteBulkString},
-{"genRedisInfoString",(unsigned long)genRedisInfoString},
-{"genericHgetallCommand",(unsigned long)genericHgetallCommand},
-{"genericZrangebyscoreCommand",(unsigned long)genericZrangebyscoreCommand},
-{"getCommand",(unsigned long)getCommand},
-{"getDecodedObject",(unsigned long)getDecodedObject},
-{"getDoubleFromObject",(unsigned long)getDoubleFromObject},
-{"getDoubleFromObjectOrReply",(unsigned long)getDoubleFromObjectOrReply},
-{"getExpire",(unsigned long)getExpire},
-{"getGenericCommand",(unsigned long)getGenericCommand},
-{"getLongFromObjectOrReply",(unsigned long)getLongFromObjectOrReply},
-{"getLongLongFromObject",(unsigned long)getLongLongFromObject},
-{"getLongLongFromObjectOrReply",(unsigned long)getLongLongFromObjectOrReply},
-{"getMcontextEip",(unsigned long)getMcontextEip},
-{"getsetCommand",(unsigned long)getsetCommand},
-{"glueReplyBuffersIfNeeded",(unsigned long)glueReplyBuffersIfNeeded},
-{"handleClientsBlockedOnSwappedKey",(unsigned long)handleClientsBlockedOnSwappedKey},
-{"handleClientsWaitingListPush",(unsigned long)handleClientsWaitingListPush},
-{"hashTypeCurrent",(unsigned long)hashTypeCurrent},
-{"hashTypeDelete",(unsigned long)hashTypeDelete},
-{"hashTypeExists",(unsigned long)hashTypeExists},
-{"hashTypeGet",(unsigned long)hashTypeGet},
-{"hashTypeInitIterator",(unsigned long)hashTypeInitIterator},
-{"hashTypeLookupWriteOrCreate",(unsigned long)hashTypeLookupWriteOrCreate},
-{"hashTypeNext",(unsigned long)hashTypeNext},
-{"hashTypeReleaseIterator",(unsigned long)hashTypeReleaseIterator},
-{"hashTypeSet",(unsigned long)hashTypeSet},
-{"hashTypeTryConversion",(unsigned long)hashTypeTryConversion},
-{"hashTypeTryObjectEncoding",(unsigned long)hashTypeTryObjectEncoding},
-{"hdelCommand",(unsigned long)hdelCommand},
-{"hexistsCommand",(unsigned long)hexistsCommand},
-{"hgetCommand",(unsigned long)hgetCommand},
-{"hgetallCommand",(unsigned long)hgetallCommand},
-{"hincrbyCommand",(unsigned long)hincrbyCommand},
-{"hkeysCommand",(unsigned long)hkeysCommand},
-{"hlenCommand",(unsigned long)hlenCommand},
-{"hmgetCommand",(unsigned long)hmgetCommand},
-{"hmsetCommand",(unsigned long)hmsetCommand},
-{"hsetCommand",(unsigned long)hsetCommand},
-{"hsetnxCommand",(unsigned long)hsetnxCommand},
-{"htNeedsResize",(unsigned long)htNeedsResize},
-{"hvalsCommand",(unsigned long)hvalsCommand},
-{"incrCommand",(unsigned long)incrCommand},
-{"incrDecrCommand",(unsigned long)incrDecrCommand},
-{"incrRefCount",(unsigned long)incrRefCount},
-{"incrbyCommand",(unsigned long)incrbyCommand},
-{"incrementallyRehash",(unsigned long)incrementallyRehash},
-{"infoCommand",(unsigned long)infoCommand},
-{"initClientMultiState",(unsigned long)initClientMultiState},
-{"initServer",(unsigned long)initServer},
-{"initServerConfig",(unsigned long)initServerConfig},
-{"isStringRepresentableAsLong",(unsigned long)isStringRepresentableAsLong},
-{"keysCommand",(unsigned long)keysCommand},
-{"lastsaveCommand",(unsigned long)lastsaveCommand},
-{"lindexCommand",(unsigned long)lindexCommand},
-{"listMatchObjects",(unsigned long)listMatchObjects},
-{"listMatchPubsubPattern",(unsigned long)listMatchPubsubPattern},
-{"ll2string",(unsigned long)ll2string},
-{"llenCommand",(unsigned long)llenCommand},
-{"loadServerConfig",(unsigned long)loadServerConfig},
-{"lockThreadedIO",(unsigned long)lockThreadedIO},
-{"lookupKey",(unsigned long)lookupKey},
-{"lookupKeyByPattern",(unsigned long)lookupKeyByPattern},
-{"lookupKeyRead",(unsigned long)lookupKeyRead},
-{"lookupKeyReadOrReply",(unsigned long)lookupKeyReadOrReply},
-{"lookupKeyWrite",(unsigned long)lookupKeyWrite},
-{"lookupKeyWriteOrReply",(unsigned long)lookupKeyWriteOrReply},
-{"lpopCommand",(unsigned long)lpopCommand},
-{"lpushCommand",(unsigned long)lpushCommand},
-{"lrangeCommand",(unsigned long)lrangeCommand},
-{"lremCommand",(unsigned long)lremCommand},
-{"lsetCommand",(unsigned long)lsetCommand},
-{"ltrimCommand",(unsigned long)ltrimCommand},
-{"mgetCommand",(unsigned long)mgetCommand},
-{"mixDigest",(unsigned long)mixDigest},
-{"mixObjectDigest",(unsigned long)mixObjectDigest},
-{"monitorCommand",(unsigned long)monitorCommand},
-{"moveCommand",(unsigned long)moveCommand},
-{"msetCommand",(unsigned long)msetCommand},
-{"msetGenericCommand",(unsigned long)msetGenericCommand},
-{"msetnxCommand",(unsigned long)msetnxCommand},
-{"multiCommand",(unsigned long)multiCommand},
-{"oom",(unsigned long)oom},
-{"pingCommand",(unsigned long)pingCommand},
-{"popGenericCommand",(unsigned long)popGenericCommand},
-{"prepareForShutdown",(unsigned long)prepareForShutdown},
-{"processCommand",(unsigned long)processCommand},
-{"processInputBuffer",(unsigned long)processInputBuffer},
-{"psubscribeCommand",(unsigned long)psubscribeCommand},
-{"publishCommand",(unsigned long)publishCommand},
-{"pubsubPublishMessage",(unsigned long)pubsubPublishMessage},
-{"pubsubSubscribeChannel",(unsigned long)pubsubSubscribeChannel},
-{"pubsubSubscribePattern",(unsigned long)pubsubSubscribePattern},
-{"pubsubUnsubscribeAllChannels",(unsigned long)pubsubUnsubscribeAllChannels},
-{"pubsubUnsubscribeAllPatterns",(unsigned long)pubsubUnsubscribeAllPatterns},
-{"pubsubUnsubscribeChannel",(unsigned long)pubsubUnsubscribeChannel},
-{"pubsubUnsubscribePattern",(unsigned long)pubsubUnsubscribePattern},
-{"punsubscribeCommand",(unsigned long)punsubscribeCommand},
-{"pushGenericCommand",(unsigned long)pushGenericCommand},
-{"qsortCompareSetsByCardinality",(unsigned long)qsortCompareSetsByCardinality},
-{"qsortCompareZsetopsrcByCardinality",(unsigned long)qsortCompareZsetopsrcByCardinality},
-{"qsortRedisCommands",(unsigned long)qsortRedisCommands},
-{"queueIOJob",(unsigned long)queueIOJob},
-{"queueMultiCommand",(unsigned long)queueMultiCommand},
-{"randomkeyCommand",(unsigned long)randomkeyCommand},
-{"rdbEncodeInteger",(unsigned long)rdbEncodeInteger},
-{"rdbGenericLoadStringObject",(unsigned long)rdbGenericLoadStringObject},
-{"rdbLoad",(unsigned long)rdbLoad},
-{"rdbLoadDoubleValue",(unsigned long)rdbLoadDoubleValue},
-{"rdbLoadEncodedStringObject",(unsigned long)rdbLoadEncodedStringObject},
-{"rdbLoadIntegerObject",(unsigned long)rdbLoadIntegerObject},
-{"rdbLoadLen",(unsigned long)rdbLoadLen},
-{"rdbLoadLzfStringObject",(unsigned long)rdbLoadLzfStringObject},
-{"rdbLoadObject",(unsigned long)rdbLoadObject},
-{"rdbLoadStringObject",(unsigned long)rdbLoadStringObject},
-{"rdbLoadTime",(unsigned long)rdbLoadTime},
-{"rdbLoadType",(unsigned long)rdbLoadType},
-{"rdbRemoveTempFile",(unsigned long)rdbRemoveTempFile},
-{"rdbSave",(unsigned long)rdbSave},
-{"rdbSaveBackground",(unsigned long)rdbSaveBackground},
-{"rdbSaveDoubleValue",(unsigned long)rdbSaveDoubleValue},
-{"rdbSaveLen",(unsigned long)rdbSaveLen},
-{"rdbSaveLzfStringObject",(unsigned long)rdbSaveLzfStringObject},
-{"rdbSaveObject",(unsigned long)rdbSaveObject},
-{"rdbSaveRawString",(unsigned long)rdbSaveRawString},
-{"rdbSaveStringObject",(unsigned long)rdbSaveStringObject},
-{"rdbSaveTime",(unsigned long)rdbSaveTime},
-{"rdbSaveType",(unsigned long)rdbSaveType},
-{"rdbSavedObjectLen",(unsigned long)rdbSavedObjectLen},
-{"rdbSavedObjectPages",(unsigned long)rdbSavedObjectPages},
-{"rdbTryIntegerEncoding",(unsigned long)rdbTryIntegerEncoding},
-{"readQueryFromClient",(unsigned long)readQueryFromClient},
-{"redisLog",(unsigned long)redisLog},
-{"removeExpire",(unsigned long)removeExpire},
-{"renameCommand",(unsigned long)renameCommand},
-{"renameGenericCommand",(unsigned long)renameGenericCommand},
-{"renamenxCommand",(unsigned long)renamenxCommand},
-{"replicationFeedMonitors",(unsigned long)replicationFeedMonitors},
-{"replicationFeedSlaves",(unsigned long)replicationFeedSlaves},
-{"resetClient",(unsigned long)resetClient},
-{"resetServerSaveParams",(unsigned long)resetServerSaveParams},
-{"rewriteAppendOnlyFile",(unsigned long)rewriteAppendOnlyFile},
-{"rewriteAppendOnlyFileBackground",(unsigned long)rewriteAppendOnlyFileBackground},
-{"rpopCommand",(unsigned long)rpopCommand},
-{"rpoplpushcommand",(unsigned long)rpoplpushcommand},
-{"rpushCommand",(unsigned long)rpushCommand},
-{"saddCommand",(unsigned long)saddCommand},
-{"saveCommand",(unsigned long)saveCommand},
-{"scardCommand",(unsigned long)scardCommand},
-{"sdiffCommand",(unsigned long)sdiffCommand},
-{"sdiffstoreCommand",(unsigned long)sdiffstoreCommand},
-{"sdscatrepr",(unsigned long)sdscatrepr},
-{"segvHandler",(unsigned long)segvHandler},
-{"selectCommand",(unsigned long)selectCommand},
-{"selectDb",(unsigned long)selectDb},
-{"sendBulkToSlave",(unsigned long)sendBulkToSlave},
-{"sendReplyToClient",(unsigned long)sendReplyToClient},
-{"sendReplyToClientWritev",(unsigned long)sendReplyToClientWritev},
-{"serverCron",(unsigned long)serverCron},
-{"setCommand",(unsigned long)setCommand},
-{"setExpire",(unsigned long)setExpire},
-{"setGenericCommand",(unsigned long)setGenericCommand},
-{"setexCommand",(unsigned long)setexCommand},
-{"setnxCommand",(unsigned long)setnxCommand},
-{"setupSigSegvAction",(unsigned long)setupSigSegvAction},
-{"shutdownCommand",(unsigned long)shutdownCommand},
-{"sigtermHandler",(unsigned long)sigtermHandler},
-{"sinterCommand",(unsigned long)sinterCommand},
-{"sinterGenericCommand",(unsigned long)sinterGenericCommand},
-{"sinterstoreCommand",(unsigned long)sinterstoreCommand},
-{"sismemberCommand",(unsigned long)sismemberCommand},
-{"slaveofCommand",(unsigned long)slaveofCommand},
-{"smoveCommand",(unsigned long)smoveCommand},
-{"sortCommand",(unsigned long)sortCommand},
-{"sortCommandTable",(unsigned long)sortCommandTable},
-{"sortCompare",(unsigned long)sortCompare},
-{"spawnIOThread",(unsigned long)spawnIOThread},
-{"spopCommand",(unsigned long)spopCommand},
-{"srandmemberCommand",(unsigned long)srandmemberCommand},
-{"sremCommand",(unsigned long)sremCommand},
-{"startAppendOnly",(unsigned long)startAppendOnly},
-{"stopAppendOnly",(unsigned long)stopAppendOnly},
-{"stringObjectLen",(unsigned long)stringObjectLen},
-{"stringmatch",(unsigned long)stringmatch},
-{"stringmatchlen",(unsigned long)stringmatchlen},
-{"subscribeCommand",(unsigned long)subscribeCommand},
-{"substrCommand",(unsigned long)substrCommand},
-{"sunionCommand",(unsigned long)sunionCommand},
-{"sunionDiffGenericCommand",(unsigned long)sunionDiffGenericCommand},
-{"sunionstoreCommand",(unsigned long)sunionstoreCommand},
-{"syncCommand",(unsigned long)syncCommand},
-{"syncRead",(unsigned long)syncRead},
-{"syncReadLine",(unsigned long)syncReadLine},
-{"syncWithMaster",(unsigned long)syncWithMaster},
-{"syncWrite",(unsigned long)syncWrite},
-{"touchWatchedKey",(unsigned long)touchWatchedKey},
-{"touchWatchedKeysOnFlush",(unsigned long)touchWatchedKeysOnFlush},
-{"tryFreeOneObjectFromFreelist",(unsigned long)tryFreeOneObjectFromFreelist},
-{"tryObjectEncoding",(unsigned long)tryObjectEncoding},
-{"tryResizeHashTables",(unsigned long)tryResizeHashTables},
-{"ttlCommand",(unsigned long)ttlCommand},
-{"typeCommand",(unsigned long)typeCommand},
-{"unblockClientWaitingData",(unsigned long)unblockClientWaitingData},
-{"unlockThreadedIO",(unsigned long)unlockThreadedIO},
-{"unsubscribeCommand",(unsigned long)unsubscribeCommand},
-{"unwatchAllKeys",(unsigned long)unwatchAllKeys},
-{"unwatchCommand",(unsigned long)unwatchCommand},
-{"updateDictResizePolicy",(unsigned long)updateDictResizePolicy},
-{"updateSlavesWaitingBgsave",(unsigned long)updateSlavesWaitingBgsave},
-{"usage",(unsigned long)usage},
-{"version",(unsigned long)version},
-{"vmCanSwapOut",(unsigned long)vmCanSwapOut},
-{"vmCancelThreadedIOJob",(unsigned long)vmCancelThreadedIOJob},
-{"vmFindContiguousPages",(unsigned long)vmFindContiguousPages},
-{"vmFreePage",(unsigned long)vmFreePage},
-{"vmGenericLoadObject",(unsigned long)vmGenericLoadObject},
-{"vmInit",(unsigned long)vmInit},
-{"vmLoadObject",(unsigned long)vmLoadObject},
-{"vmMarkPageFree",(unsigned long)vmMarkPageFree},
-{"vmMarkPageUsed",(unsigned long)vmMarkPageUsed},
-{"vmMarkPagesFree",(unsigned long)vmMarkPagesFree},
-{"vmMarkPagesUsed",(unsigned long)vmMarkPagesUsed},
-{"vmPreviewObject",(unsigned long)vmPreviewObject},
-{"vmReadObjectFromSwap",(unsigned long)vmReadObjectFromSwap},
-{"vmReopenSwapFile",(unsigned long)vmReopenSwapFile},
-{"vmSwapObjectBlocking",(unsigned long)vmSwapObjectBlocking},
-{"vmSwapObjectThreaded",(unsigned long)vmSwapObjectThreaded},
-{"vmSwapOneObject",(unsigned long)vmSwapOneObject},
-{"vmSwapOneObjectBlocking",(unsigned long)vmSwapOneObjectBlocking},
-{"vmSwapOneObjectThreaded",(unsigned long)vmSwapOneObjectThreaded},
-{"vmThreadedIOCompletedJob",(unsigned long)vmThreadedIOCompletedJob},
-{"vmWriteObjectOnSwap",(unsigned long)vmWriteObjectOnSwap},
-{"waitEmptyIOJobsQueue",(unsigned long)waitEmptyIOJobsQueue},
-{"waitForMultipleSwappedKeys",(unsigned long)waitForMultipleSwappedKeys},
-{"waitForSwappedKey",(unsigned long)waitForSwappedKey},
-{"watchCommand",(unsigned long)watchCommand},
-{"watchForKey",(unsigned long)watchForKey},
-{"xorDigest",(unsigned long)xorDigest},
-{"xorObjectDigest",(unsigned long)xorObjectDigest},
-{"yesnotoi",(unsigned long)yesnotoi},
-{"zaddCommand",(unsigned long)zaddCommand},
-{"zaddGenericCommand",(unsigned long)zaddGenericCommand},
-{"zcardCommand",(unsigned long)zcardCommand},
-{"zcountCommand",(unsigned long)zcountCommand},
-{"zincrbyCommand",(unsigned long)zincrbyCommand},
-{"zinterstoreCommand",(unsigned long)zinterstoreCommand},
-{"zrangeCommand",(unsigned long)zrangeCommand},
-{"zrangeGenericCommand",(unsigned long)zrangeGenericCommand},
-{"zrangebyscoreCommand",(unsigned long)zrangebyscoreCommand},
-{"zrankCommand",(unsigned long)zrankCommand},
-{"zrankGenericCommand",(unsigned long)zrankGenericCommand},
-{"zremCommand",(unsigned long)zremCommand},
-{"zremrangebyrankCommand",(unsigned long)zremrangebyrankCommand},
-{"zremrangebyscoreCommand",(unsigned long)zremrangebyscoreCommand},
-{"zrevrangeCommand",(unsigned long)zrevrangeCommand},
-{"zrevrankCommand",(unsigned long)zrevrankCommand},
-{"zscoreCommand",(unsigned long)zscoreCommand},
-{"zslCreate",(unsigned long)zslCreate},
-{"zslCreateNode",(unsigned long)zslCreateNode},
-{"zslDelete",(unsigned long)zslDelete},
-{"zslFirstWithScore",(unsigned long)zslFirstWithScore},
-{"zslFree",(unsigned long)zslFree},
-{"zslFreeNode",(unsigned long)zslFreeNode},
-{"zslInsert",(unsigned long)zslInsert},
-{"zslRandomLevel",(unsigned long)zslRandomLevel},
-{"zunionInterBlockClientOnSwappedKeys",(unsigned long)zunionInterBlockClientOnSwappedKeys},
-{"zunionInterGenericCommand",(unsigned long)zunionInterGenericCommand},
-{"zunionstoreCommand",(unsigned long)zunionstoreCommand},
-{NULL,0}
-};

tests/integration/aof.tcl

@@ -59,13 +59,13 @@ tags {"aof"} {
     ## Test that redis-check-aof indeed sees this AOF is not valid
     test {Short read: Utility should confirm the AOF is not valid} {
         catch {
-            exec ./redis-check-aof $aof_path
+            exec src/redis-check-aof $aof_path
         } str
         set _ $str
     } {*not valid*}
 
     test {Short read: Utility should be able to fix the AOF} {
-        exec echo y | ./redis-check-aof --fix $aof_path
+        exec echo y | src/redis-check-aof --fix $aof_path
     } {*Successfully truncated AOF*}
 
     ## Test that the server can be started using the truncated AOF

tests/support/server.tcl

@@ -169,10 +169,10 @@ proc start_server {options {code undefined}} {
     set stderr [format "%s/%s" [dict get $config "dir"] "stderr"]
 
     if {$::valgrind} {
-        exec valgrind ./redis-server $config_file > $stdout 2> $stderr &
+        exec valgrind src/redis-server $config_file > $stdout 2> $stderr &
         after 2000
     } else {
-        exec ./redis-server $config_file > $stdout 2> $stderr &
+        exec src/redis-server $config_file > $stdout 2> $stderr &
         after 500
     }