40 lines
667 B
C
40 lines
667 B
C
/* contrib/ltree/crc32.c */
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/*
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* Implements CRC-32, as used in ltree.
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*
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* Note that the CRC is used in the on-disk format of GiST indexes, so we
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* must stay backwards-compatible!
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*/
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#include "postgres.h"
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#ifdef LOWER_NODE
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#include <ctype.h>
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#define TOLOWER(x) tolower((unsigned char) (x))
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#else
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#define TOLOWER(x) (x)
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#endif
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#include "crc32.h"
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#include "utils/pg_crc.h"
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unsigned int
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ltree_crc32_sz(char *buf, int size)
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{
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pg_crc32 crc;
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char *p = buf;
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INIT_TRADITIONAL_CRC32(crc);
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while (size > 0)
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{
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char c = (char) TOLOWER(*p);
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COMP_TRADITIONAL_CRC32(crc, &c, 1);
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size--;
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p++;
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}
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FIN_TRADITIONAL_CRC32(crc);
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return (unsigned int) crc;
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}
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