includes/GlobalFunctions.php

   1 <?php
   2 # Global functions used everywhere
   3
   4 $wgNumberOfArticles = -1; # Unset
   5 $wgTotalViews = -1;
   6 $wgTotalEdits = -1;
   7
   8 require_once( 'DatabaseFunctions.php' );
   9 require_once( 'UpdateClasses.php' );
  10 require_once( 'LogPage.php' );
  11
  12 /*
  13  * Compatibility functions
  14  */
  15
  16 # PHP <4.3.x is not actively supported; 4.1.x and 4.2.x might or might not work.
  17 # <4.1.x will not work, as we use a number of features introduced in 4.1.0
  18 # such as the new autoglobals.
  19
  20 if( !function_exists('iconv') ) {
  21         # iconv support is not in the default configuration and so may not be present.
  22         # Assume will only ever use utf-8 and iso-8859-1.
  23         # This will *not* work in all circumstances.
  24         function iconv( $from, $to, $string ) {
  25                 if(strcasecmp( $from, $to ) == 0) return $string;
  26                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  27                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  28                 return $string;
  29         }
  30 }
  31
  32 if( !function_exists('file_get_contents') ) {
  33         # Exists in PHP 4.3.0+
  34         function file_get_contents( $filename ) {
  35                 return implode( '', file( $filename ) );
  36         }
  37 }
  38
  39 if( !function_exists('is_a') ) {
  40         # Exists in PHP 4.2.0+
  41         function is_a( $object, $class_name ) {
  42                 return
  43                         (strcasecmp( get_class( $object, $class_name ) == 0) ||
  44                          is_subclass_of( $object, $class_name ) );
  45         }
  46 }
  47
  48 # html_entity_decode exists in PHP 4.3.0+ but is FATALLY BROKEN even then,
  49 # with no UTF-8 support.
  50 function do_html_entity_decode( $string, $quote_style=ENT_COMPAT, $charset='ISO-8859-1' ) {
  51         static $trans;
  52         if( !isset( $trans ) ) {
  53                 $trans = array_flip( get_html_translation_table( HTML_ENTITIES, $quote_style ) );
  54                 # Assumes $charset will always be the same through a run, and only understands
  55                 # utf-8 or default. Note - mixing latin1 named entities and unicode numbered
  56                 # ones will result in a bad link.
  57                 if( strcasecmp( 'utf-8', $charset ) == 0 ) {
  58                         $trans = array_map( 'utf8_encode', $trans );
  59                 }
  60         }
  61         return strtr( $string, $trans );
  62 }
  63
  64 $wgRandomSeeded = false;
  65
  66 function wfSeedRandom()
  67 {
  68         global $wgRandomSeeded;
  69
  70         if ( ! $wgRandomSeeded ) {
  71                 $seed = hexdec(substr(md5(microtime()),-8)) & 0x7fffffff;
  72                 mt_srand( $seed );
  73                 $wgRandomSeeded = true;
  74         }
  75 }
  76
  77 # Generates a URL from a URL-encoded title and a query string
  78 # Title::getLocalURL() is preferred in most cases
  79 #
  80 function wfLocalUrl( $a, $q = '' )
  81 {
  82         global $wgServer, $wgScript, $wgArticlePath;
  83
  84         $a = str_replace( ' ', '_', $a );
  85
  86         if ( '' == $a ) {
  87                 if( '' == $q ) {
  88                         $a = $wgScript;
  89                 } else {
  90                         $a = "{$wgScript}?{$q}";
  91                 }
  92         } else if ( '' == $q ) {
  93                 $a = str_replace( "$1", $a, $wgArticlePath );
  94         } else if ($wgScript != '' ) {
  95                 $a = "{$wgScript}?title={$a}&{$q}";
  96         } else { //XXX hackish solution for toplevel wikis
  97                 $a = "/{$a}?{$q}";
  98         }
  99         return $a;
 100 }
 101
 102 function wfLocalUrlE( $a, $q = '' )
 103 {
 104         return wfEscapeHTML( wfLocalUrl( $a, $q ) );
 105         # die( "Call to obsolete function wfLocalUrlE()" );
 106 }
 107
 108 function wfFullUrl( $a, $q = '' ) {
 109         wfDebugDieBacktrace( 'Call to obsolete function wfFullUrl(); use Title::getFullURL' );
 110 }
 111
 112 function wfFullUrlE( $a, $q = '' ) {
 113         wfDebugDieBacktrace( 'Call to obsolete function wfFullUrlE(); use Title::getFullUrlE' );
 114
 115 }
 116
 117 // orphan function wfThumbUrl( $img )
 118 //{
 119 //      global $wgUploadPath;
 120 //
 121 //      $nt = Title::newFromText( $img );
 122 //      if( !$nt ) return "";
 123 //
 124 //      $name = $nt->getDBkey();
 125 //      $hash = md5( $name );
 126 //
 127 //      $url = "{$wgUploadPath}/thumb/" . $hash{0} . "/" .
 128 //        substr( $hash, 0, 2 ) . "/{$name}";
 129 //      return wfUrlencode( $url );
 130 //}
 131
 132
 133 function wfImageArchiveUrl( $name )
 134 {
 135         global $wgUploadPath;
 136
 137         $hash = md5( substr( $name, 15) );
 138         $url = "{$wgUploadPath}/archive/" . $hash{0} . "/" .
 139           substr( $hash, 0, 2 ) . "/{$name}";
 140         return wfUrlencode($url);
 141 }
 142
 143 function wfUrlencode ( $s )
 144 {
 145         $s = urlencode( $s );
 146         $s = preg_replace( '/%3[Aa]/', ':', $s );
 147         $s = preg_replace( '/%2[Ff]/', '/', $s );
 148
 149         return $s;
 150 }
 151
 152 function wfUtf8Sequence($codepoint) {
 153         if($codepoint <         0x80) return chr($codepoint);
 154         if($codepoint <    0x800) return chr($codepoint >>      6 & 0x3f | 0xc0) .
 155                                                                          chr($codepoint           & 0x3f | 0x80);
 156         if($codepoint <  0x10000) return chr($codepoint >> 12 & 0x0f | 0xe0) .
 157                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 158                                                                          chr($codepoint           & 0x3f | 0x80);
 159         if($codepoint < 0x100000) return chr($codepoint >> 18 & 0x07 | 0xf0) . # Double-check this
 160                                                                          chr($codepoint >> 12 & 0x3f | 0x80) .
 161                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 162                                                                          chr($codepoint           & 0x3f | 0x80);
 163         # Doesn't yet handle outside the BMP
 164         return "&#$codepoint;";
 165 }
 166
 167 # Converts numeric character entities to UTF-8
 168 function wfMungeToUtf8($string) {
 169         global $wgInputEncoding; # This is debatable
 170         #$string = iconv($wgInputEncoding, "UTF-8", $string);
 171         $string = preg_replace ( '/&#([0-9]+);/e', 'wfUtf8Sequence($1)', $string );
 172         $string = preg_replace ( '/&#x([0-9a-f]+);/ie', 'wfUtf8Sequence(0x$1)', $string );
 173         # Should also do named entities here
 174         return $string;
 175 }
 176
 177 # Converts a single UTF-8 character into the corresponding HTML character entity
 178 function wfUtf8Entity( $matches ) {
 179         $char = $matches[0];
 180         # Find the length
 181         $z = ord( $char{0} );
 182         if ( $z & 0x80 ) {
 183                 $length = 0;
 184                 while ( $z & 0x80 ) {
 185                         $length++;
 186                         $z <<= 1;
 187                 }
 188         } else {
 189                 $length = 1;
 190         }
 191
 192         if ( $length != strlen( $char ) ) {
 193                 return '';
 194         }
 195         if ( $length == 1 ) {
 196                 return $char;
 197         }
 198
 199         # Mask off the length-determining bits and shift back to the original location
 200         $z &= 0xff;
 201         $z >>= $length;
 202
 203         # Add in the free bits from subsequent bytes
 204         for ( $i=1; $i<$length; $i++ ) {
 205                 $z <<= 6;
 206                 $z |= ord( $char{$i} ) & 0x3f;
 207         }
 208
 209         # Make entity
 210         return "&#$z;";
 211 }
 212
 213 # Converts all multi-byte characters in a UTF-8 string into the appropriate character entity
 214 function wfUtf8ToHTML($string) {
 215         return preg_replace_callback( '/[\\xc0-\\xfd][\\x80-\\xbf]*/', 'wfUtf8Entity', $string );
 216 }
 217
 218 function wfDebug( $text, $logonly = false )
 219 {
 220         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly;
 221
 222         if ( isset( $wgOut ) && $wgDebugComments && !$logonly ) {
 223                 $wgOut->debug( $text );
 224         }
 225         if ( "" != $wgDebugLogFile && !$wgProfileOnly ) {
 226                 error_log( $text, 3, $wgDebugLogFile );
 227         }
 228 }
 229
 230 function logProfilingData()
 231 {
 232         global $wgRequestTime, $wgDebugLogFile;
 233         global $wgProfiling, $wgProfileStack, $wgProfileLimit, $wgUser;
 234         $now = wfTime();
 235
 236         list( $usec, $sec ) = explode( " ", $wgRequestTime );
 237         $start = (float)$sec + (float)$usec;
 238         $elapsed = $now - $start;
 239         if ( $wgProfiling ) {
 240                 $prof = wfGetProfilingOutput( $start, $elapsed );
 241                 $forward = '';
 242                 if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 243                         $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 244                 if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 245                         $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 246                 if( !empty( $_SERVER['HTTP_FROM'] ) )
 247                         $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 248                 if( $forward )
 249                         $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 250                 if($wgUser->getId() == 0)
 251                         $forward .= ' anon';
 252                 $log = sprintf( "%s\t%04.3f\t%s\n",
 253                   gmdate( 'YmdHis' ), $elapsed,
 254                   urldecode( $_SERVER['REQUEST_URI'] . $forward ) );
 255                 if ( '' != $wgDebugLogFile ) {
 256                         error_log( $log . $prof, 3, $wgDebugLogFile );
 257                 }
 258         }
 259 }
 260
 261
 262 function wfReadOnly()
 263 {
 264         global $wgReadOnlyFile;
 265
 266         if ( "" == $wgReadOnlyFile ) { return false; }
 267         return is_file( $wgReadOnlyFile );
 268 }
 269
 270 $wgReplacementKeys = array( "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", "$9" );
 271
 272 # Get a message from anywhere
 273 function wfMsg( $key ) {
 274         $args = func_get_args();
 275         if ( count( $args ) ) {
 276                 array_shift( $args );
 277         }
 278         return wfMsgReal( $key, $args, true );
 279 }
 280
 281 # Get a message from the language file
 282 function wfMsgNoDB( $key ) {
 283         $args = func_get_args();
 284         if ( count( $args ) ) {
 285                 array_shift( $args );
 286         }
 287         return wfMsgReal( $key, $args, false );
 288 }
 289
 290 # Really get a message
 291 function wfMsgReal( $key, $args, $useDB ) {
 292         global $wgReplacementKeys, $wgMessageCache, $wgLang;
 293
 294         $fname = 'wfMsg';
 295         wfProfileIn( $fname );
 296         if ( $wgMessageCache ) {
 297                 $message = $wgMessageCache->get( $key, $useDB );
 298         } elseif ( $wgLang ) {
 299                 $message = $wgLang->getMessage( $key );
 300         } else {
 301                 wfDebug( "No language object when getting $key\n" );
 302                 $message = "&lt;$key&gt;";
 303         }
 304
 305         # Replace arguments
 306         if( count( $args ) ) {
 307                 $message = str_replace( $wgReplacementKeys, $args, $message );
 308         }
 309         wfProfileOut( $fname );
 310         return $message;
 311 }
 312
 313 function wfCleanFormFields( $fields )
 314 {
 315         wfDebugDieBacktrace( 'Call to obsolete wfCleanFormFields(). Use wgRequest instead...' );
 316 }
 317
 318 function wfMungeQuotes( $in )
 319 {
 320         $out = str_replace( '%', '%25', $in );
 321         $out = str_replace( "'", '%27', $out );
 322         $out = str_replace( '"', '%22', $out );
 323         return $out;
 324 }
 325
 326 function wfDemungeQuotes( $in )
 327 {
 328         $out = str_replace( '%22', '"', $in );
 329         $out = str_replace( '%27', "'", $out );
 330         $out = str_replace( '%25', '%', $out );
 331         return $out;
 332 }
 333
 334 function wfCleanQueryVar( $var )
 335 {
 336         wfDebugDieBacktrace( 'Call to obsolete function wfCleanQueryVar(); use wgRequest instead' );
 337 }
 338
 339 function wfSearch( $s )
 340 {
 341         $se = new SearchEngine( $s );
 342         $se->showResults();
 343 }
 344
 345 function wfGo( $s )
 346 { # pick the nearest match
 347         $se = new SearchEngine( $s );
 348         $se->goResult();
 349 }
 350
 351 # Just like exit() but makes a note of it.
 352 function wfAbruptExit(){
 353         static $called = false;
 354         if ( $called ){
 355                 exit();
 356         }
 357         $called = true;
 358
 359         if( function_exists( 'debug_backtrace' ) ){ // PHP >= 4.3
 360                 $bt = debug_backtrace();
 361                 for($i = 0; $i < count($bt) ; $i++){
 362                         $file = $bt[$i]['file'];
 363                         $line = $bt[$i]['line'];
 364                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 365                 }
 366         } else {
 367                 wfDebug('WARNING: Abrupt exit\n');
 368         }
 369         exit();
 370 }
 371
 372 function wfDebugDieBacktrace( $msg = '' ) {
 373         if ( function_exists( 'debug_backtrace' ) ) {
 374                 $msg .= "\n<p>Backtrace:</p>\n<ul>\n";
 375                 $backtrace = debug_backtrace();
 376                 foreach( $backtrace as $call ) {
 377                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 378                         $file = $f[count($f)-1];
 379                         $msg .= '<li>' . $file . " line " . $call['line'] . ', in ';
 380                         if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 381                         $msg .= $call['function'] . "()</li>\n";
 382                 }
 383          }
 384          die( $msg );
 385 }
 386
 387 function wfNumberOfArticles()
 388 {
 389         global $wgNumberOfArticles;
 390
 391         wfLoadSiteStats();
 392         return $wgNumberOfArticles;
 393 }
 394
 395 /* private */ function wfLoadSiteStats()
 396 {
 397         global $wgNumberOfArticles, $wgTotalViews, $wgTotalEdits;
 398         if ( -1 != $wgNumberOfArticles ) return;
 399
 400         $sql = 'SELECT ss_total_views, ss_total_edits, ss_good_articles ' .
 401           'FROM site_stats WHERE ss_row_id=1';
 402         $res = wfQuery( $sql, DB_READ, 'wfLoadSiteStats' );
 403
 404         if ( 0 == wfNumRows( $res ) ) { return; }
 405         else {
 406                 $s = wfFetchObject( $res );
 407                 $wgTotalViews = $s->ss_total_views;
 408                 $wgTotalEdits = $s->ss_total_edits;
 409                 $wgNumberOfArticles = $s->ss_good_articles;
 410         }
 411 }
 412
 413 function wfEscapeHTML( $in )
 414 {
 415         return str_replace(
 416                 array( '&', '"', '>', '<' ),
 417                 array( '&amp;', '&quot;', '&gt;', '&lt;' ),
 418                 $in );
 419 }
 420
 421 function wfEscapeHTMLTagsOnly( $in ) {
 422         return str_replace(
 423                 array( '"', '>', '<' ),
 424                 array( '&quot;', '&gt;', '&lt;' ),
 425                 $in );
 426 }
 427
 428 function wfUnescapeHTML( $in )
 429 {
 430         $in = str_replace( '&lt;', '<', $in );
 431         $in = str_replace( '&gt;', '>', $in );
 432         $in = str_replace( '&quot;', '"', $in );
 433         $in = str_replace( '&amp;', '&', $in );
 434         return $in;
 435 }
 436
 437 function wfImageDir( $fname )
 438 {
 439         global $wgUploadDirectory;
 440
 441         $hash = md5( $fname );
 442         $oldumask = umask(0);
 443         $dest = $wgUploadDirectory . '/' . $hash{0};
 444         if ( ! is_dir( $dest ) ) { mkdir( $dest, 0777 ); }
 445         $dest .= '/' . substr( $hash, 0, 2 );
 446         if ( ! is_dir( $dest ) ) { mkdir( $dest, 0777 ); }
 447
 448         umask( $oldumask );
 449         return $dest;
 450 }
 451
 452 function wfImageThumbDir( $fname , $subdir='thumb')
 453 {
 454         return wfImageArchiveDir( $fname, $subdir );
 455 }
 456
 457 function wfImageArchiveDir( $fname , $subdir='archive')
 458 {
 459         global $wgUploadDirectory;
 460
 461         $hash = md5( $fname );
 462         $oldumask = umask(0);
 463
 464         # Suppress warning messages here; if the file itself can't
 465         # be written we'll worry about it then.
 466         $archive = "{$wgUploadDirectory}/{$subdir}";
 467         if ( ! is_dir( $archive ) ) { @mkdir( $archive, 0777 ); }
 468         $archive .= '/' . $hash{0};
 469         if ( ! is_dir( $archive ) ) { @mkdir( $archive, 0777 ); }
 470         $archive .= '/' . substr( $hash, 0, 2 );
 471         if ( ! is_dir( $archive ) ) { @mkdir( $archive, 0777 ); }
 472
 473         umask( $oldumask );
 474         return $archive;
 475 }
 476
 477 function wfRecordUpload( $name, $oldver, $size, $desc, $copyStatus = "", $source = "" )
 478 {
 479         global $wgUser, $wgLang, $wgTitle, $wgOut, $wgDeferredUpdateList;
 480         global $wgUseCopyrightUpload;
 481
 482         $fname = 'wfRecordUpload';
 483
 484         $sql = 'SELECT img_name,img_size,img_timestamp,img_description,img_user,' .
 485           "img_user_text FROM image WHERE img_name='" . wfStrencode( $name ) . "'";
 486         $res = wfQuery( $sql, DB_READ, $fname );
 487
 488         $now = wfTimestampNow();
 489         $won = wfInvertTimestamp( $now );
 490         $size = IntVal( $size );
 491
 492         if ( $wgUseCopyrightUpload )
 493           {
 494                 $textdesc = '== ' . wfMsg ( 'filedesc' ) . " ==\n" . $desc . "\n" .
 495                   '== ' . wfMsg ( 'filestatus' ) . " ==\n" . $copyStatus . "\n" .
 496                   '== ' . wfMsg ( 'filesource' ) . " ==\n" . $source ;
 497           }
 498         else $textdesc = $desc ;
 499
 500         $now = wfTimestampNow();
 501         $won = wfInvertTimestamp( $now );
 502
 503         if ( 0 == wfNumRows( $res ) ) {
 504                 $sql = 'INSERT INTO image (img_name,img_size,img_timestamp,' .
 505                   "img_description,img_user,img_user_text) VALUES ('" .
 506                   wfStrencode( $name ) . "',$size,'{$now}','" .
 507                   wfStrencode( $desc ) . "', '" . $wgUser->getID() .
 508                   "', '" . wfStrencode( $wgUser->getName() ) . "')";
 509                 wfQuery( $sql, DB_WRITE, $fname );
 510
 511                 $sql = 'SELECT cur_id,cur_text FROM cur WHERE cur_namespace=' .
 512                   Namespace::getImage() . " AND cur_title='" .
 513                   wfStrencode( $name ) . "'";
 514                 $res = wfQuery( $sql, DB_READ, $fname );
 515                 if ( 0 == wfNumRows( $res ) ) {
 516                         $common =
 517                           Namespace::getImage() . ",'" .
 518                           wfStrencode( $name ) . "','" .
 519                           wfStrencode( $desc ) . "','" . $wgUser->getID() . "','" .
 520                           wfStrencode( $wgUser->getName() ) . "','" . $now .
 521                           "',1";
 522                         $sql = 'INSERT INTO cur (cur_namespace,cur_title,' .
 523                           'cur_comment,cur_user,cur_user_text,cur_timestamp,cur_is_new,' .
 524                           'cur_text,inverse_timestamp,cur_touched) VALUES (' .
 525                           $common .
 526                           ",'" . wfStrencode( $textdesc ) . "','{$won}','{$now}')";
 527                         wfQuery( $sql, DB_WRITE, $fname );
 528                         $id = wfInsertId() or 0; # We should throw an error instead
 529
 530                         $titleObj = Title::makeTitle( NS_IMAGE, $name );
 531                         RecentChange::notifyNew( $now, $titleObj, 0, $wgUser, $desc );
 532
 533                         $u = new SearchUpdate( $id, $name, $desc );
 534                         $u->doUpdate();
 535                 }
 536         } else {
 537                 $s = wfFetchObject( $res );
 538
 539                 $sql = 'INSERT INTO oldimage (oi_name,oi_archive_name,oi_size,' .
 540                   "oi_timestamp,oi_description,oi_user,oi_user_text) VALUES ('" .
 541                   wfStrencode( $s->img_name ) . "','" .
 542                   wfStrencode( $oldver ) .
 543                   "',{$s->img_size},'{$s->img_timestamp}','" .
 544                   wfStrencode( $s->img_description ) . "','" .
 545                   wfStrencode( $s->img_user ) . "','" .
 546                   wfStrencode( $s->img_user_text) . "')";
 547                 wfQuery( $sql, DB_WRITE, $fname );
 548
 549                 $sql = "UPDATE image SET img_size={$size}," .
 550                   "img_timestamp='" . wfTimestampNow() . "',img_user='" .
 551                   $wgUser->getID() . "',img_user_text='" .
 552                   wfStrencode( $wgUser->getName() ) . "', img_description='" .
 553                   wfStrencode( $desc ) . "' WHERE img_name='" .
 554                   wfStrencode( $name ) . "'";
 555                 wfQuery( $sql, DB_WRITE, $fname );
 556
 557                 $sql = "UPDATE cur SET cur_touched='{$now}' WHERE cur_namespace=" .
 558                   Namespace::getImage() . " AND cur_title='" .
 559                   wfStrencode( $name ) . "'";
 560                 wfQuery( $sql, DB_WRITE, $fname );
 561         }
 562
 563         $log = new LogPage( wfMsg( 'uploadlogpage' ), wfMsg( 'uploadlogpagetext' ) );
 564         $da = wfMsg( 'uploadedimage', '[[:' . $wgLang->getNsText(
 565           Namespace::getImage() ) . ":{$name}|{$name}]]" );
 566         $ta = wfMsg( 'uploadedimage', $name );
 567         $log->addEntry( $da, $desc, $ta );
 568 }
 569
 570
 571 /* Some generic result counters, pulled out of SearchEngine */
 572
 573 function wfShowingResults( $offset, $limit )
 574 {
 575         global $wgLang;
 576         return wfMsg( 'showingresults', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 577 }
 578
 579 function wfShowingResultsNum( $offset, $limit, $num )
 580 {
 581         global $wgLang;
 582         return wfMsg( 'showingresultsnum', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 583 }
 584
 585 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false )
 586 {
 587         global $wgUser, $wgLang;
 588         $fmtLimit = $wgLang->formatNum( $limit );
 589         $prev = wfMsg( 'prevn', $fmtLimit );
 590         $next = wfMsg( 'nextn', $fmtLimit );
 591         $link = wfUrlencode( $link );
 592
 593         $sk = $wgUser->getSkin();
 594         if ( 0 != $offset ) {
 595                 $po = $offset - $limit;
 596                 if ( $po < 0 ) { $po = 0; }
 597                 $q = "limit={$limit}&offset={$po}";
 598                 if ( '' != $query ) { $q .= "&{$query}"; }
 599                 $plink = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$prev}</a>";
 600         } else { $plink = $prev; }
 601
 602         $no = $offset + $limit;
 603         $q = "limit={$limit}&offset={$no}";
 604         if ( "" != $query ) { $q .= "&{$query}"; }
 605
 606         if ( $atend ) {
 607                 $nlink = $next;
 608         } else {
 609                 $nlink = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$next}</a>";
 610         }
 611         $nums = wfNumLink( $offset, 20, $link , $query ) . ' | ' .
 612           wfNumLink( $offset, 50, $link, $query ) . ' | ' .
 613           wfNumLink( $offset, 100, $link, $query ) . ' | ' .
 614           wfNumLink( $offset, 250, $link, $query ) . ' | ' .
 615           wfNumLink( $offset, 500, $link, $query );
 616
 617         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 618 }
 619
 620 function wfNumLink( $offset, $limit, $link, $query = '' )
 621 {
 622         global $wgUser, $wgLang;
 623         if ( '' == $query ) { $q = ''; }
 624         else { $q = "{$query}&"; }
 625         $q .= "limit={$limit}&offset={$offset}";
 626
 627         $fmtLimit = $wgLang->formatNum( $limit );
 628         $s = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$fmtLimit}</a>";
 629         return $s;
 630 }
 631
 632 function wfClientAcceptsGzip() {
 633         global $wgUseGzip;
 634         if( $wgUseGzip ) {
 635                 # FIXME: we may want to blacklist some broken browsers
 636                 if( preg_match(
 637                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 638                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 639                         $m ) ) {
 640                         if( ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 641                         wfDebug( " accepts gzip\n" );
 642                         return true;
 643                 }
 644         }
 645         return false;
 646 }
 647
 648 # Yay, more global functions!
 649 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 650         global $wgUser, $wgRequest;
 651
 652         $limit = $wgRequest->getInt( 'limit', 0 );
 653         if( $limit < 0 ) $limit = 0;
 654         if( ( $limit == 0 ) && ( $optionname != '' ) ) {
 655                 $limit = (int)$wgUser->getOption( $optionname );
 656         }
 657         if( $limit <= 0 ) $limit = $deflimit;
 658         if( $limit > 5000 ) $limit = 5000; # We have *some* limits...
 659
 660         $offset = $wgRequest->getInt( 'offset', 0 );
 661         if( $offset < 0 ) $offset = 0;
 662         if( $offset > 65000 ) $offset = 65000; # do we need a max? what?
 663
 664         return array( $limit, $offset );
 665 }
 666
 667 # Escapes the given text so that it may be output using addWikiText()
 668 # without any linking, formatting, etc. making its way through. This
 669 # is achieved by substituting certain characters with HTML entities.
 670 # As required by the callers, <nowiki> is not used. It currently does
 671 # not filter out characters which have special meaning only at the
 672 # start of a line, such as "*".
 673 function wfEscapeWikiText( $text )
 674 {
 675         $text = str_replace(
 676                 array( '[',             '|',      "'",     'ISBN '        , '://'         , "\n=" ),
 677                 array( '&#91;', '&#124;', '&#39;', 'ISBN&#32;', '&#58;//' , "\n&#61;" ),
 678                 htmlspecialchars($text) );
 679         return $text;
 680 }
 681
 682 function wfQuotedPrintable( $string, $charset = '' )
 683 {
 684         # Probably incomplete; see RFC 2045
 685         if( empty( $charset ) ) {
 686                 global $wgInputEncoding;
 687                 $charset = $wgInputEncoding;
 688         }
 689         $charset = strtoupper( $charset );
 690         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 691
 692         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 693         $replace = $illegal . '\t ?_';
 694         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 695         $out = "=?$charset?Q?";
 696         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 697         $out .= '?=';
 698         return $out;
 699 }
 700
 701 function wfTime(){
 702         $st = explode( ' ', microtime() );
 703         return (float)$st[0] + (float)$st[1];
 704 }
 705
 706 # Changes the first character to an HTML entity
 707 function wfHtmlEscapeFirst( $text ) {
 708         $ord = ord($text);
 709         $newText = substr($text, 1);
 710         return "&#$ord;$newText";
 711 }
 712
 713 # Sets dest to source and returns the original value of dest
 714 function wfSetVar( &$dest, $source )
 715 {
 716         $temp = $dest;
 717         $dest = $source;
 718         return $temp;
 719 }
 720
 721 # Sets dest to a reference to source and returns the original dest
 722 # Pity that doesn't work in PHP
 723 function &wfSetRef( &$dest, &$source )
 724 {
 725         die( "You can't rebind a variable in the caller's scope" );
 726 }
 727
 728 # This function takes two arrays as input, and returns a CGI-style string, e.g.
 729 # "days=7&limit=100". Options in the first array override options in the second.
 730 # Options set to "" will not be output.
 731 function wfArrayToCGI( $array1, $array2 = NULL )
 732 {
 733         if ( !is_null( $array2 ) ) {
 734                 $array1 = $array1 + $array2;
 735         }
 736
 737         $cgi = '';
 738         foreach ( $array1 as $key => $value ) {
 739                 if ( '' !== $value ) {
 740                         if ( '' != $cgi ) {
 741                                 $cgi .= '&';
 742                         }
 743                         $cgi .= "{$key}={$value}";
 744                 }
 745         }
 746         return $cgi;
 747 }
 748
 749 # This is obsolete, use SquidUpdate::purge()
 750 function wfPurgeSquidServers ($urlArr) {
 751         SquidUpdate::purge( $urlArr );
 752 }
 753
 754 # Windows-compatible version of escapeshellarg()
 755 function wfEscapeShellArg( )
 756 {
 757         $args = func_get_args();
 758         $first = true;
 759         $retVal = '';
 760         foreach ( $args as $arg ) {
 761                 if ( !$first ) {
 762                         $retVal .= ' ';
 763                 } else {
 764                         $first = false;
 765                 }
 766
 767                 if ( wfIsWindows() ) {
 768                         $retVal .= '"' . str_replace( '"','\"', $arg ) . '"';
 769                 } else {
 770                         $retVal .= escapeshellarg( $arg );
 771                 }
 772         }
 773         return $retVal;
 774 }
 775
 776 # wfMerge attempts to merge differences between three texts.
 777 # Returns true for a clean merge and false for failure or a conflict.
 778
 779 function wfMerge( $old, $mine, $yours, &$result ){
 780         global $wgDiff3;
 781
 782         # This check may also protect against code injection in
 783         # case of broken installations.
 784         if(! file_exists( $wgDiff3 ) ){
 785                 return false;
 786         }
 787
 788         # Make temporary files
 789         $td = '/tmp/';
 790         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
 791         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
 792         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
 793
 794         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
 795         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
 796         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
 797
 798         # Check for a conflict
 799         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
 800           wfEscapeShellArg( $mytextName ) . ' ' .
 801           wfEscapeShellArg( $oldtextName ) . ' ' .
 802           wfEscapeShellArg( $yourtextName );
 803         $handle = popen( $cmd, 'r' );
 804
 805         if( fgets( $handle ) ){
 806                 $conflict = true;
 807         } else {
 808                 $conflict = false;
 809         }
 810         pclose( $handle );
 811
 812         # Merge differences
 813         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
 814           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
 815         $handle = popen( $cmd, 'r' );
 816         $result = '';
 817         do {
 818                 $data = fread( $handle, 8192 );
 819                 if ( strlen( $data ) == 0 ) {
 820                         break;
 821                 }
 822                 $result .= $data;
 823         } while ( true );
 824         pclose( $handle );
 825         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
 826         return ! $conflict;
 827 }
 828
 829 function wfVarDump( $var )
 830 {
 831         global $wgOut;
 832         $s = str_replace("\n","<br>\n", var_export( $var, true ) . "\n");
 833         if ( headers_sent() || !@is_object( $wgOut ) ) {
 834                 print $s;
 835         } else {
 836                 $wgOut->addHTML( $s );
 837         }
 838 }
 839
 840 # Provide a simple HTTP error.
 841 function wfHttpError( $code, $label, $desc ) {
 842         global $wgOut;
 843         $wgOut->disable();
 844         header( "HTTP/1.0 $code $label" );
 845         header( "Status: $code $label" );
 846         $wgOut->sendCacheControl();
 847
 848         # Don't send content if it's a HEAD request.
 849         if( $_SERVER['REQUEST_METHOD'] == 'HEAD' ) {
 850                 header( 'Content-type: text/plain' );
 851                 print "$desc\n";
 852         }
 853 }
 854
 855 # Converts an Accept-* header into an array mapping string values to quality factors
 856 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
 857         # No arg means accept anything (per HTTP spec)
 858         if( !$accept ) {
 859                 return array( $def => 1 );
 860         }
 861
 862         $prefs = array();
 863
 864         $parts = explode( ',', $accept );
 865
 866         foreach( $parts as $part ) {
 867                 # FIXME: doesn't deal with params like 'text/html; level=1'
 868                 @list( $value, $qpart ) = explode( ';', $part );
 869                 if( !isset( $qpart ) ) {
 870                         $prefs[$value] = 1;
 871                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
 872                         $prefs[$value] = $match[1];
 873                 }
 874         }
 875
 876         return $prefs;
 877 }
 878
 879 /* private */ function mimeTypeMatch( $type, $avail ) {
 880         if( array_key_exists($type, $avail) ) {
 881                 return $type;
 882         } else {
 883                 $parts = explode( '/', $type );
 884                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
 885                         return $parts[0] . '/*';
 886                 } elseif( array_key_exists( '*/*', $avail ) ) {
 887                         return '*/*';
 888                 } else {
 889                         return NULL;
 890                 }
 891         }
 892 }
 893
 894 # FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
 895 # XXX: generalize to negotiate other stuff
 896 function wfNegotiateType( $cprefs, $sprefs ) {
 897         $combine = array();
 898
 899         foreach( array_keys($sprefs) as $type ) {
 900                 $parts = explode( '/', $type );
 901                 if( $parts[1] != '*' ) {
 902                         $ckey = mimeTypeMatch( $type, $cprefs );
 903                         if( $ckey ) {
 904                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
 905                         }
 906                 }
 907         }
 908
 909         foreach( array_keys( $cprefs ) as $type ) {
 910                 $parts = explode( '/', $type );
 911                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
 912                         $skey = mimeTypeMatch( $type, $sprefs );
 913                         if( $skey ) {
 914                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
 915                         }
 916                 }
 917         }
 918
 919         $bestq = 0;
 920         $besttype = NULL;
 921
 922         foreach( array_keys( $combine ) as $type ) {
 923                 if( $combine[$type] > $bestq ) {
 924                         $besttype = $type;
 925                         $bestq = $combine[$type];
 926                 }
 927         }
 928
 929         return $besttype;
 930 }
 931
 932 # Array lookup
 933 # Returns an array where the values in the first array are replaced by the
 934 # values in the second array with the corresponding keys
 935 function wfArrayLookup( $a, $b )
 936 {
 937         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 938 }
 939
 940 # Since Windows is so different to any of the other popular OSes, it seems appropriate
 941 # to have a simple way to test for its presence
 942 function wfIsWindows() {
 943         if (substr(php_uname(), 0, 7) == 'Windows') {
 944                 return true;
 945         } else {
 946                 return false;
 947         }
 948 }
 949
 950 ?>