xref: /dokuwiki/lib/exe/fetch.php (revision dc57ef04af4d12bb589c98e7457a22c44a091815)
1<?php
2/**
3 * DokuWiki media passthrough file
4 *
5 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
6 * @author     Andreas Gohr <andi@splitbrain.org>
7 */
8
9  if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
10	require_once(DOKU_INC.'inc/init.php');
11	require_once(DOKU_INC.'inc/common.php');
12  require_once(DOKU_INC.'inc/pageutils.php');
13  require_once(DOKU_INC.'inc/confutils.php');
14  require_once(DOKU_INC.'inc/auth.php');
15  $mimetypes = getMimeTypes();
16
17	//get input
18	$MEDIA  = $_REQUEST['media'];
19	$CACHE  = calc_cache($_REQUEST['cache']);
20	$WIDTH  = $_REQUEST['w'];
21	$HEIGHT = $_REQUEST['h'];
22  list($EXT,$MIME) = mimetype($MEDIA);
23  if($EXT === false){
24    $EXT  = 'unknown';
25    $MIME = 'application/octet-stream';
26  }
27
28	//media to local file
29	if(preg_match('#^(https?|ftp)://#i',$MEDIA)){
30    //handle external media
31  	$FILE = get_from_URL($MEDIA,$EXT,$CACHE);
32    if(!$FILE){
33      //download failed - redirect to original URL
34      header('Location: '.$MEDIA);
35      exit;
36    }
37  }else{
38    $MEDIA = cleanID($MEDIA);
39    if(empty($MEDIA)){
40      header("HTTP/1.0 400 Bad Request");
41      print 'Bad request';
42      exit;
43    }
44
45    //check permissions (namespace only)
46    if(auth_quickaclcheck(getNS($MEDIA).':X') < AUTH_READ){
47      header("HTTP/1.0 401 Unauthorized");
48      //fixme add some image for imagefiles
49      print 'Unauthorized';
50      exit;
51    }
52    $FILE  = mediaFN($MEDIA);
53  }
54
55  //check file existance
56  if(!@file_exists($FILE)){
57    header("HTTP/1.0 404 Not Found");
58    //FIXME add some default broken image
59    print 'Not Found';
60    exit;
61  }
62
63  //handle image resizing
64  if((substr($MIME,0,5) == 'image') && $WIDTH){
65    $FILE = get_resized($FILE,$EXT,$WIDTH,$HEIGHT);
66  }
67
68
69  //FIXME set sane cachecontrol headers
70  //FIXME handle conditional and partial requests
71
72  //send file
73  header("Content-Type: $MIME");
74  header('Last-Modified: '.date('r',filemtime($FILE)));
75  header('Content-Length: '.filesize($FILE));
76  header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
77
78  //application mime type is downloadable
79  if(substr($MIME,0,11) == 'application'){
80    header('Content-Disposition: attachment; filename="'.basename($FILE).'"');
81  }
82
83  $fp = @fopen($FILE,"rb");
84  if($fp){
85    fpassthru($fp); //does a close itself
86  }else{
87    header("HTTP/1.0 500 Internal Server Error");
88    print "Could not read $FILE - bad permissions?";
89  }
90
91/* ------------------------------------------------------------------------ */
92
93/**
94 * Resizes the given image to the given size
95 *
96 * @author  Andreas Gohr <andi@splitbrain.org>
97 */
98function get_resized($file, $ext, $w, $h=0){
99  global $conf;
100
101  $md5   = md5($file);
102  $info  = getimagesize($file);
103  if(!$h) $h = round(($w * $info[1]) / $info[0]);
104
105
106  //cache
107  $local = $conf['mediadir'].'/_cache/'.$md5.'.'.$w.'x'.$h.'.'.$ext;
108  $mtime = @filemtime($local); // 0 if not exists
109
110  if( $mtime > filemtime($file) || resize_image($ext,$file,$info[0],$info[1],$local,$w,$h) ){
111    return $local;
112  }
113  //still here? resizing failed
114  return $file;
115}
116
117/**
118 * Returns the wanted cachetime in seconds
119 *
120 * Resolves named constants
121 *
122 * @author  Andreas Gohr <andi@splitbrain.org>
123 */
124function calc_cache($cache){
125  global $conf;
126
127  if(strtolower($cache) == 'nocache') return 0; //never cache
128  if(strtolower($cache) == 'recache') return $conf['cachetime']; //use standard cache
129  return -1; //cache endless
130}
131
132/**
133 * Download a remote file and return local filename
134 *
135 * returns false if download fails. Uses cached file if available and
136 * wanted
137 *
138 * @author  Andreas Gohr <andi@splitbrain.org>
139 */
140function get_from_URL($url,$ext,$cache){
141  global $conf;
142
143  $url = strtolower($url);
144  $md5 = md5($url);
145
146  $local = $conf['mediadir']."/_cache/$md5.$ext";
147  $mtime = @filemtime($local); // 0 if not exists
148
149  //decide if download needed:
150
151  //  never cache     exists but no endless cache     not exists or expired
152  if( $cache == 0 || ($mtime != 0 && $cache != -1) || $mtime < time()-$cache ){
153    if(io_download($url,$local)){
154      return $local;
155    }else{
156      return false;
157    }
158  }
159
160  //if cache exists use it else
161  if($mtime) return $local;
162
163  //else return false
164  return false;
165}
166
167/**
168 * resize images
169 *
170 * @author Andreas Gohr <andi@splitbrain.org>
171 */
172function resize_image($ext,$from,$from_w,$from_h,$to,$to_w,$to_h){
173  global $conf;
174
175  if($conf['gdlib'] < 1) return false; //no GDlib available or wanted
176
177  // create an image of the given filetype
178  if ($ext == 'jpg' || $ext == 'jpeg'){
179    if(!function_exists("imagecreatefromjpeg")) return false;
180    $image = @imagecreatefromjpeg($from);
181  }elseif($ext == 'png') {
182    if(!function_exists("imagecreatefrompng")) return false;
183    $image = @imagecreatefrompng($from);
184
185  }elseif($ext == 'gif') {
186    if(!function_exists("imagecreatefromgif")) return false;
187    $image = @imagecreatefromgif($from);
188  }
189  if(!$image) return false;
190
191  if(($conf['gdlib']>1) && function_exists("imagecreatetruecolor")){
192    $newimg = @imagecreatetruecolor ($to_w, $to_h);
193  }
194  if(!$newimg) $newimg = @imagecreate($to_w, $to_h);
195  if(!$newimg) return false;
196
197  //keep png alpha channel if possible
198  if($ext == 'png' && $conf['gdlib']>1 && function_exists('imagesavealpha')){
199    imagealphablending($newimg, false);
200    imagesavealpha($newimg,true);
201  }
202
203  // create cachedir
204  io_makeFileDir($to);
205
206  //try resampling first
207  if(function_exists("imagecopyresampled")){
208    if(!@imagecopyresampled($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h)) {
209      imagecopyresized($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h);
210    }
211  }else{
212    imagecopyresized($newimg, $image, 0, 0, 0, 0, $to_w, $to_h, $from_w, $from_h);
213  }
214
215  if ($ext == 'jpg' || $ext == 'jpeg'){
216    if(!function_exists("imagejpeg")) return false;
217    return imagejpeg($newimg, $to, 70);
218  }elseif($ext == 'png') {
219    if(!function_exists("imagepng")) return false;
220    return imagepng($newimg, $to);
221  }elseif($ext == 'gif') {
222    if(!function_exists("imagegif")) return false;
223    return imagegif($newimg, $to);
224  }
225
226  return false;
227}
228
229
230//Setup VIM: ex: et ts=2 enc=utf-8 :
231?>
232