dokuwiki/lib/exe/fetch.php

405 lines
11 KiB
PHP

<?php
/**
* DokuWiki media passthrough file
*
* @license GPL 2 (http://www.gnu.org/licenses/gpl.html)
* @author Andreas Gohr <andi@splitbrain.org>
*/
if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
define('DOKU_DISABLE_GZIP_OUTPUT', 1);
require_once(DOKU_INC.'inc/init.php');
require_once(DOKU_INC.'inc/common.php');
require_once(DOKU_INC.'inc/pageutils.php');
require_once(DOKU_INC.'inc/confutils.php');
require_once(DOKU_INC.'inc/auth.php');
//close sesseion
session_write_close();
if(!defined('CHUNK_SIZE')) define('CHUNK_SIZE',16*1024);
$mimetypes = getMimeTypes();
//get input
$MEDIA = getID('media',false); // no cleaning - maybe external
$CACHE = calc_cache($_REQUEST['cache']);
$WIDTH = $_REQUEST['w'];
$HEIGHT = $_REQUEST['h'];
list($EXT,$MIME) = mimetype($MEDIA);
if($EXT === false){
$EXT = 'unknown';
$MIME = 'application/octet-stream';
}
//media to local file
if(preg_match('#^(https?|ftp)://#i',$MEDIA)){
//handle external media
$FILE = get_from_URL($MEDIA,$EXT,$CACHE);
if(!$FILE){
//download failed - redirect to original URL
header('Location: '.$MEDIA);
exit;
}
}else{
$MEDIA = cleanID($MEDIA);
if(empty($MEDIA)){
header("HTTP/1.0 400 Bad Request");
print 'Bad request';
exit;
}
//check permissions (namespace only)
if(auth_quickaclcheck(getNS($MEDIA).':X') < AUTH_READ){
header("HTTP/1.0 401 Unauthorized");
//fixme add some image for imagefiles
print 'Unauthorized';
exit;
}
$FILE = mediaFN($MEDIA);
}
//check file existance
if(!@file_exists($FILE)){
header("HTTP/1.0 404 Not Found");
//FIXME add some default broken image
print 'Not Found';
exit;
}
//handle image resizing
if((substr($MIME,0,5) == 'image') && $WIDTH){
$FILE = get_resized($FILE,$EXT,$WIDTH,$HEIGHT);
}
// finally send the file to the client
sendFile($FILE,$MIME,$CACHE);
/* ------------------------------------------------------------------------ */
/**
* Set headers and send the file to the client
*
* @author Andreas Gohr <andi@splitbrain.org>
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function sendFile($file,$mime,$cache){
global $conf;
$fmtime = filemtime($file);
// send headers
header("Content-Type: $mime");
// smart http caching headers
if ($cache==-1) {
// cache
// cachetime or one hour
header('Expires: '.gmdate("D, d M Y H:i:s", time()+max($conf['cachetime'], 3600)).' GMT');
header('Cache-Control: public, proxy-revalidate, no-transform, max-age='.max($conf['cachetime'], 3600));
header('Pragma: public');
} else if ($cache>0) {
// recache
// remaining cachetime + 10 seconds so the newly recached media is used
header('Expires: '.gmdate("D, d M Y H:i:s", $fmtime+$conf['cachetime']+10).' GMT');
header('Cache-Control: public, proxy-revalidate, no-transform, max-age='.max($fmtime-time()+$conf['cachetime']+10, 0));
header('Pragma: public');
} else if ($cache==0) {
// nocache
header('Cache-Control: must-revalidate, no-transform, post-check=0, pre-check=0');
header('Pragma: public');
}
header('Accept-Ranges: bytes');
//send important headers first, script stops here if '304 Not Modified' response
http_conditionalRequest($fmtime);
list($start,$len) = http_rangeRequest(filesize($file));
//application mime type is downloadable
if(substr($mime,0,11) == 'application'){
header('Content-Disposition: attachment; filename="'.basename($file).'";');
}
// send file contents
$fp = @fopen($file,"rb");
if($fp){
fseek($fp,$start); //seek to start of range
$chunk = ($len > CHUNK_SIZE) ? CHUNK_SIZE : $len;
while (!feof($fp) && $chunk > 0) {
@set_time_limit(); // large files can take a lot of time
print fread($fp, $chunk);
flush();
$len -= $chunk;
$chunk = ($len > CHUNK_SIZE) ? CHUNK_SIZE : $len;
}
fclose($fp);
}else{
header("HTTP/1.0 500 Internal Server Error");
print "Could not read $file - bad permissions?";
}
}
/**
* Checks and sets headers to handle range requets
*
* @author Andreas Gohr <andi@splitbrain.org>
* @returns array The start byte and the amount of bytes to send
*/
function http_rangeRequest($size){
if(!isset($_SERVER['HTTP_RANGE'])){
// no range requested - send the whole file
header("Content-Length: $size");
return array(0,$size);
}
$t = explode('=', $_SERVER['HTTP_RANGE']);
if (!$t[0]=='bytes') {
// we only understand byte ranges - send the whole file
header("Content-Length: $size");
return array(0,$size);
}
$r = explode('-', $t[1]);
$start = (int)$r[0];
$end = (int)$r[1];
if (!$end) $end = $size - 1;
if ($start > $end || $start > $size || $end > $size){
header('HTTP/1.1 416 Requested Range Not Satisfiable');
print 'Bad Range Request!';
exit;
}
$tot = $end - $start + 1;
header('HTTP/1.1 206 Partial Content');
header("Content-Range: bytes {$start}-{$end}/{$size}");
header("Content-Length: $tot");
return array($start,$tot);
}
/**
* Resizes the given image to the given size
*
* @author Andreas Gohr <andi@splitbrain.org>
*/
function get_resized($file, $ext, $w, $h=0){
global $conf;
$info = getimagesize($file);
if(!$h) $h = round(($w * $info[1]) / $info[0]);
//cache
$local = getCacheName($file,'.media.'.$w.'x'.$h.'.'.$ext);
$mtime = @filemtime($local); // 0 if not exists
if( $mtime > filemtime($file) ||
resize_imageIM($ext,$file,$info[0],$info[1],$local,$w,$h) ||
resize_imageGD($ext,$file,$info[0],$info[1],$local,$w,$h) ){
return $local;
}
//still here? resizing failed
return $file;
}
/**
* Returns the wanted cachetime in seconds
*
* Resolves named constants
*
* @author Andreas Gohr <andi@splitbrain.org>
*/
function calc_cache($cache){
global $conf;
if(strtolower($cache) == 'nocache') return 0; //never cache
if(strtolower($cache) == 'recache') return $conf['cachetime']; //use standard cache
return -1; //cache endless
}
/**
* Download a remote file and return local filename
*
* returns false if download fails. Uses cached file if available and
* wanted
*
* @author Andreas Gohr <andi@splitbrain.org>
* @author Pavel Vitis <Pavel.Vitis@seznam.cz>
*/
function get_from_URL($url,$ext,$cache){
global $conf;
// if 'nocache' just redirect
if ($cache==0) { return false; }
$local = getCacheName(strtolower($url),".media.$ext");
$mtime = @filemtime($local); // 0 if not exists
//decide if download needed:
if( ($mtime == 0) || // cache does not exist
($cache != -1 && $mtime < time()-$cache) // 'recache' and cache has expired
){
if(io_download($url,$local)){
return $local;
}else{
return false;
}
}
//if cache exists use it else
if($mtime) return $local;
//else return false
return false;
}
/**
* resize images using external ImageMagick convert program
*
* @author Pavel Vitis <Pavel.Vitis@seznam.cz>
* @author Andreas Gohr <andi@splitbrain.org>
*/
function resize_imageIM($ext,$from,$from_w,$from_h,$to,$to_w,$to_h){
global $conf;
// check if convert is configured
if(!$conf['im_convert']) return false;
// prepare command
$cmd = $conf['im_convert'];
$cmd .= ' -resize '.$to_w.'x'.$to_h.'!';
if ($ext == 'jpg' || $ext == 'jpeg') {
$cmd .= ' -quality '.$conf['jpg_quality'];
}
$cmd .= " $from $to";
@exec($cmd,$out,$retval);
if ($retval == 0) return true;
return false;
}
/**
* resize images using PHP's libGD support
*
* @author Andreas Gohr <andi@splitbrain.org>
*/
function resize_imageGD($ext,$from,$from_w,$from_h,$to,$to_w,$to_h){
global $conf;
if($conf['gdlib'] < 1) return false; //no GDlib available or wanted
// check available memory
if(!is_mem_available(($from_w * $from_h * 4) + ($to_w * $to_h * 4))){
return false;
}
// create an image of the given filetype
if ($ext == 'jpg' || $ext == 'jpeg'){
if(!function_exists("imagecreatefromjpeg")) return false;
$image = @imagecreatefromjpeg($from);
}elseif($ext == 'png') {
if(!function_exists("imagecreatefrompng")) return false;
$image = @imagecreatefrompng($from);
}elseif($ext == 'gif') {
if(!function_exists("imagecreatefromgif")) return false;
$image = @imagecreatefromgif($from);
}
if(!$image) return false;
if(($conf['gdlib']>1) && function_exists("imagecreatetruecolor")){
$newimg = @imagecreatetruecolor ($to_w, $to_h);
}
if(!$newimg) $newimg = @imagecreate($to_w, $to_h);
if(!$newimg){
imagedestroy($image);
return false;
}
//keep png alpha channel if possible
if($ext == 'png' && $conf['gdlib']>1 && function_exists('imagesavealpha')){
imagealphablending($newimg, false);
imagesavealpha($newimg,true);
}
//try resampling first
if(function_exists("imagecopyresampled")){
if(!@imagecopyresampled($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h)) {
imagecopyresized($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h);
}
}else{
imagecopyresized($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h);
}
$okay = false;
if ($ext == 'jpg' || $ext == 'jpeg'){
if(!function_exists('imagejpeg')){
$okay = false;
}else{
$okay = imagejpeg($newimg, $to, $conf['jpg_quality']);
}
}elseif($ext == 'png') {
if(!function_exists('imagepng')){
$okay = false;
}else{
$okay = imagepng($newimg, $to);
}
}elseif($ext == 'gif') {
if(!function_exists('imagegif')){
$okay = false;
}else{
$okay = imagegif($newimg, $to);
}
}
// destroy GD image ressources
if($image) imagedestroy($image);
if($newimg) imagedestroy($newimg);
return $okay;
}
/**
* Checks if the given amount of memory is available
*
* If the memory_get_usage() function is not available the
* function just assumes $used bytes of already allocated memory
*
* @param int $mem Size of memory you want to allocate in bytes
* @param int $used already allocated memory (see above)
* @author Filip Oscadal <webmaster@illusionsoftworks.cz>
* @author Andreas Gohr <andi@splitbrain.org>
*/
function is_mem_available($mem,$bytes=1048576){
$limit = trim(ini_get('memory_limit'));
if(empty($limit)) return true; // no limit set!
// parse limit to bytes
$unit = strtolower(substr($limit,-1));
switch($unit){
case 'g':
$limit = substr($limit,0,-1);
$limit *= 1024*1024*1024;
break;
case 'm':
$limit = substr($limit,0,-1);
$limit *= 1024*1024;
break;
case 'k':
$limit = substr($limit,0,-1);
$limit *= 1024;
break;
}
// get used memory if possible
if(function_exists('memory_get_usage')){
$used = memory_get_usage();
}
if($used+$mem > $limit){
return false;
}
return true;
}
//Setup VIM: ex: et ts=2 enc=utf-8 :
?>