includes/GlobalFunctions.php

   1 <?php
   2
   3 /**
   4  * Global functions used everywhere
   5  * @package MediaWiki
   6  */
   7
   8 /**
   9  * Some globals and requires needed
  10  */
  11
  12 /**
  13  * Total number of articles
  14  * @global integer $wgNumberOfArticles
  15  */
  16 $wgNumberOfArticles = -1; # Unset
  17 /**
  18  * Total number of views
  19  * @global integer $wgTotalViews
  20  */
  21 $wgTotalViews = -1;
  22 /**
  23  * Total number of edits
  24  * @global integer $wgTotalEdits
  25  */
  26 $wgTotalEdits = -1;
  27
  28
  29 require_once( 'DatabaseFunctions.php' );
  30 require_once( 'UpdateClasses.php' );
  31 require_once( 'LogPage.php' );
  32 require_once( 'normal/UtfNormalUtil.php' );
  33
  34 /**
  35  * Compatibility functions
  36  * PHP <4.3.x is not actively supported; 4.1.x and 4.2.x might or might not work.
  37  * <4.1.x will not work, as we use a number of features introduced in 4.1.0
  38  * such as the new autoglobals.
  39  */
  40 if( !function_exists('iconv') ) {
  41         # iconv support is not in the default configuration and so may not be present.
  42         # Assume will only ever use utf-8 and iso-8859-1.
  43         # This will *not* work in all circumstances.
  44         function iconv( $from, $to, $string ) {
  45                 if(strcasecmp( $from, $to ) == 0) return $string;
  46                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  47                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  48                 return $string;
  49         }
  50 }
  51
  52 if( !function_exists('file_get_contents') ) {
  53         # Exists in PHP 4.3.0+
  54         function file_get_contents( $filename ) {
  55                 return implode( '', file( $filename ) );
  56         }
  57 }
  58
  59 if( !function_exists('is_a') ) {
  60         # Exists in PHP 4.2.0+
  61         function is_a( $object, $class_name ) {
  62                 return
  63                         (strcasecmp( get_class( $object ), $class_name ) == 0) ||
  64                          is_subclass_of( $object, $class_name );
  65         }
  66 }
  67
  68 # UTF-8 substr function based on a PHP manual comment
  69 if ( !function_exists( 'mb_substr' ) ) {
  70         function mb_substr( $str, $start ) {
  71                 preg_match_all( '/./us', $str, $ar );
  72
  73                 if( func_num_args() >= 3 ) {
  74                         $end = func_get_arg( 2 );
  75                         return join( '', array_slice( $ar[0], $start, $end ) );
  76                 } else {
  77                         return join( '', array_slice( $ar[0], $start ) );
  78                 }
  79         }
  80 }
  81
  82 /**
  83  * html_entity_decode exists in PHP 4.3.0+ but is FATALLY BROKEN even then,
  84  * with no UTF-8 support.
  85  *
  86  * @param string $string String having html entities
  87  * @param $quote_style
  88  * @param string $charset Encoding set to use (default 'ISO-8859-1')
  89  */
  90 function do_html_entity_decode( $string, $quote_style=ENT_COMPAT, $charset='ISO-8859-1' ) {
  91         $fname = 'do_html_entity_decode';
  92         wfProfileIn( $fname );
  93
  94         static $trans;
  95         static $savedCharset;
  96         static $regexp;
  97         if( !isset( $trans ) || $savedCharset != $charset ) {
  98                 $trans = array_flip( get_html_translation_table( HTML_ENTITIES, $quote_style ) );
  99                 $savedCharset = $charset;
 100
 101                 # Note - mixing latin1 named entities and unicode numbered
 102                 # ones will result in a bad link.
 103                 if( strcasecmp( 'utf-8', $charset ) == 0 ) {
 104                         $trans = array_map( 'utf8_encode', $trans );
 105                 }
 106
 107                 /**
 108                  * Most links will _not_ contain these fun guys,
 109                  * and on long pages with many links we can get
 110                  * called a lot.
 111                  *
 112                  * A regular expression search is faster than
 113                  * a strtr or str_replace with a hundred-ish
 114                  * entries, though it may be slower to actually
 115                  * replace things.
 116                  *
 117                  * They all look like '&xxxx;'...
 118                  */
 119                 foreach( $trans as $key => $val ) {
 120                         $snip[] = substr( $key, 1, -1 );
 121                 }
 122                 $regexp = '/(&(?:' . implode( '|', $snip ) . ');)/e';
 123         }
 124
 125         $out = preg_replace( $regexp, '$trans["$1"]', $string );
 126         wfProfileOut( $fname );
 127         return $out;
 128 }
 129
 130
 131 /**
 132  * Where as we got a random seed
 133  * @var bool $wgTotalViews
 134  */
 135 $wgRandomSeeded = false;
 136
 137 /**
 138  * Seed Mersenne Twister
 139  * Only necessary in PHP < 4.2.0
 140  *
 141  * @return bool
 142  */
 143 function wfSeedRandom() {
 144         global $wgRandomSeeded;
 145
 146         if ( ! $wgRandomSeeded && version_compare( phpversion(), '4.2.0' ) < 0 ) {
 147                 $seed = hexdec(substr(md5(microtime()),-8)) & 0x7fffffff;
 148                 mt_srand( $seed );
 149                 $wgRandomSeeded = true;
 150         }
 151 }
 152
 153 /**
 154  * Get a random decimal value between 0 and 1, in a way
 155  * not likely to give duplicate values for any realistic
 156  * number of articles.
 157  *
 158  * @return string
 159  */
 160 function wfRandom() {
 161         # The maximum random value is "only" 2^31-1, so get two random
 162         # values to reduce the chance of dupes
 163         $max = mt_getrandmax();
 164         $rand = number_format( mt_rand() * mt_rand()
 165                 / $max / $max, 12, '.', '' );
 166         return $rand;
 167 }
 168
 169 /**
 170  * We want / and : to be included as literal characters in our title URLs.
 171  * %2F in the page titles seems to fatally break for some reason.
 172  *
 173  * @param string $s
 174  * @return string
 175 */
 176 function wfUrlencode ( $s ) {
 177         $s = urlencode( $s );
 178         $s = preg_replace( '/%3[Aa]/', ':', $s );
 179         $s = preg_replace( '/%2[Ff]/', '/', $s );
 180
 181         return $s;
 182 }
 183
 184 /**
 185  * Return the UTF-8 sequence for a given Unicode code point.
 186  * Currently doesn't work for values outside the Basic Multilingual Plane.
 187  *
 188  * @param string $codepoint UTF-8 code point.
 189  * @return string HTML UTF-8 Entitie such as '&#1234;'.
 190  */
 191 function wfUtf8Sequence( $codepoint ) {
 192         if($codepoint <         0x80) return chr($codepoint);
 193         if($codepoint <    0x800) return chr($codepoint >>      6 & 0x3f | 0xc0) .
 194                                                                          chr($codepoint           & 0x3f | 0x80);
 195         if($codepoint <  0x10000) return chr($codepoint >> 12 & 0x0f | 0xe0) .
 196                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 197                                                                          chr($codepoint           & 0x3f | 0x80);
 198         if($codepoint < 0x110000) return chr($codepoint >> 18 & 0x07 | 0xf0) .
 199                                                                          chr($codepoint >> 12 & 0x3f | 0x80) .
 200                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 201                                                                          chr($codepoint           & 0x3f | 0x80);
 202
 203         # There should be no assigned code points outside this range, but...
 204         return "&#$codepoint;";
 205 }
 206
 207 /**
 208  * Converts numeric character entities to UTF-8
 209  *
 210  * @param string $string String to convert.
 211  * @return string Converted string.
 212  */
 213 function wfMungeToUtf8( $string ) {
 214         global $wgInputEncoding; # This is debatable
 215         #$string = iconv($wgInputEncoding, "UTF-8", $string);
 216         $string = preg_replace ( '/&#([0-9]+);/e', 'wfUtf8Sequence($1)', $string );
 217         $string = preg_replace ( '/&#x([0-9a-f]+);/ie', 'wfUtf8Sequence(0x$1)', $string );
 218         # Should also do named entities here
 219         return $string;
 220 }
 221
 222 /**
 223  * Converts a single UTF-8 character into the corresponding HTML character
 224  * entity (for use with preg_replace_callback)
 225  *
 226  * @param array $matches
 227  *
 228  */
 229 function wfUtf8Entity( $matches ) {
 230         $codepoint = utf8ToCodepoint( $matches[0] );
 231         return "&#$codepoint;";
 232 }
 233
 234 /**
 235  * Converts all multi-byte characters in a UTF-8 string into the appropriate
 236  * character entity
 237  */
 238 function wfUtf8ToHTML($string) {
 239         return preg_replace_callback( '/[\\xc0-\\xfd][\\x80-\\xbf]*/', 'wfUtf8Entity', $string );
 240 }
 241
 242 /**
 243  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 244  * In normal operation this is a NOP.
 245  *
 246  * Controlling globals:
 247  * $wgDebugLogFile - points to the log file
 248  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 249  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 250  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 251  *
 252  * @param string $text
 253  * @param bool $logonly Set true to avoid appearing in HTML when $wgDebugComments is set
 254  */
 255 function wfDebug( $text, $logonly = false ) {
 256         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 257
 258         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 259         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 260                 return;
 261         }
 262
 263         if ( isset( $wgOut ) && $wgDebugComments && !$logonly ) {
 264                 $wgOut->debug( $text );
 265         }
 266         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 267                 error_log( $text, 3, $wgDebugLogFile );
 268         }
 269 }
 270
 271 /**
 272  * Log for database errors
 273  * @param string $text Database error message.
 274  */
 275 function wfLogDBError( $text ) {
 276         global $wgDBerrorLog;
 277         if ( $wgDBerrorLog ) {
 278                 $text = date('D M j G:i:s T Y') . "\t".$text;
 279                 error_log( $text, 3, $wgDBerrorLog );
 280         }
 281 }
 282
 283 /**
 284  * @todo document
 285  */
 286 function logProfilingData() {
 287         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 288         global $wgProfiling, $wgProfileStack, $wgProfileLimit, $wgUser;
 289         $now = wfTime();
 290
 291         list( $usec, $sec ) = explode( ' ', $wgRequestTime );
 292         $start = (float)$sec + (float)$usec;
 293         $elapsed = $now - $start;
 294         if ( $wgProfiling ) {
 295                 $prof = wfGetProfilingOutput( $start, $elapsed );
 296                 $forward = '';
 297                 if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 298                         $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 299                 if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 300                         $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 301                 if( !empty( $_SERVER['HTTP_FROM'] ) )
 302                         $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 303                 if( $forward )
 304                         $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 305                 if($wgUser->getId() == 0)
 306                         $forward .= ' anon';
 307                 $log = sprintf( "%s\t%04.3f\t%s\n",
 308                   gmdate( 'YmdHis' ), $elapsed,
 309                   urldecode( $_SERVER['REQUEST_URI'] . $forward ) );
 310                 if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 311                         error_log( $log . $prof, 3, $wgDebugLogFile );
 312                 }
 313         }
 314 }
 315
 316 /**
 317  * Check if the wiki read-only lock file is present. This can be used to lock
 318  * off editing functions, but doesn't guarantee that the database will not be
 319  * modified.
 320  * @return bool
 321  */
 322 function wfReadOnly() {
 323         global $wgReadOnlyFile;
 324
 325         if ( '' == $wgReadOnlyFile ) {
 326                 return false;
 327         }
 328         return is_file( $wgReadOnlyFile );
 329 }
 330
 331
 332 /**
 333  * Get a message from anywhere, for the UI elements
 334  */
 335 function wfMsg( $key ) {
 336         $args = func_get_args();
 337         array_shift( $args );
 338         return wfMsgReal( $key, $args, true );
 339 }
 340
 341 /**
 342  * Get a message from anywhere, for the content
 343  */
 344 function wfMsgForContent( $key ) {
 345         $args = func_get_args();
 346         array_shift( $args );
 347         return wfMsgReal( $key, $args, true, true );
 348 }
 349
 350 /**
 351  * Get a message from the language file, for the UI elements
 352  */
 353 function wfMsgNoDB( $key ) {
 354         $args = func_get_args();
 355         array_shift( $args );
 356         return wfMsgReal( $key, $args, false );
 357 }
 358
 359 /**
 360  * Get a message from the language file, for the content
 361  */
 362 function wfMsgNoDBForContent( $key ) {
 363         $args = func_get_args();
 364         array_shift( $args );
 365         return wfMsgReal( $key, $args, false, true );
 366 }
 367
 368
 369 /**
 370  * Really get a message
 371  */
 372 function wfMsgReal( $key, $args, $useDB, $forContent=false ) {
 373         static $replacementKeys = array( '$1', '$2', '$3', '$4', '$5', '$6', '$7', '$8', '$9' );
 374         global $wgParser, $wgMsgParserOptions;
 375         global $wgContLang, $wgLanguageCode;
 376         global $wgMessageCache, $wgLang;
 377
 378         $fname = 'wfMsgReal';
 379         wfProfileIn( $fname );
 380
 381         if( $forContent ) {
 382                 /**
 383                  * Message is needed for page content, and needs
 384                  * to be consistent with the site's configured
 385                  * language. It might be part of a page title,
 386                  * or a link, or text that will go into the
 387                  * parser cache and be served back to other
 388                  * visitors.
 389                  */
 390                 $cache = &$wgMessageCache;
 391                 $lang = &$wgContLang;
 392         } else {
 393                 /**
 394                  * Message is for display purposes only.
 395                  * The user may have selected a conversion-based
 396                  * language variant or a separate user interface
 397                  * language; if so use that.
 398                  */
 399                 if ( is_object( $wgContLang ) ) {
 400                         if( in_array( $wgLanguageCode, $wgContLang->getVariants() ) ) {
 401                                 $cache = &$wgMessageCache;
 402                                 $lang = &$wgLang;
 403                         } else {
 404                                 $cache = false;
 405                                 $lang = &$wgLang;
 406                         }
 407                 } else {
 408                         $cache = false;
 409                         $lang = false;
 410                 }
 411         }
 412
 413
 414         if( is_object( $cache ) ) {
 415                 $message = $cache->get( $key, $useDB, $forContent );
 416         } else {
 417                 if ( !is_object( $lang ) ) {
 418                         $lang = new Language;
 419                 }
 420
 421                 wfSuppressWarnings();
 422                 $message = $lang->getMessage( $key );
 423                 wfRestoreWarnings();
 424                 if(!$message)
 425                         $message = Language::getMessage($key);
 426                 if(strstr($message, '{{' ) !== false) {
 427                         $message = $wgParser->transformMsg($message, $wgMsgParserOptions);
 428                 }
 429         }
 430
 431         # Replace arguments
 432         if( count( $args ) ) {
 433                 $message = str_replace( $replacementKeys, $args, $message );
 434         }
 435         wfProfileOut( $fname );
 436         return $message;
 437 }
 438
 439
 440
 441 /**
 442  * Just like exit() but makes a note of it.
 443  * Commits open transactions except if the error parameter is set
 444  */
 445 function wfAbruptExit( $error = false ){
 446         global $wgLoadBalancer;
 447         static $called = false;
 448         if ( $called ){
 449                 exit();
 450         }
 451         $called = true;
 452
 453         if( function_exists( 'debug_backtrace' ) ){ // PHP >= 4.3
 454                 $bt = debug_backtrace();
 455                 for($i = 0; $i < count($bt) ; $i++){
 456                         $file = $bt[$i]['file'];
 457                         $line = $bt[$i]['line'];
 458                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 459                 }
 460         } else {
 461                 wfDebug('WARNING: Abrupt exit\n');
 462         }
 463         if ( !$error ) {
 464                 $wgLoadBalancer->closeAll();
 465         }
 466         exit();
 467 }
 468
 469 /**
 470  * @todo document
 471  */
 472 function wfErrorExit() {
 473         wfAbruptExit( true );
 474 }
 475
 476 /**
 477  * Die with a backtrace
 478  * This is meant as a debugging aid to track down where bad data comes from.
 479  * Shouldn't be used in production code except maybe in "shouldn't happen" areas.
 480  *
 481  * @param string $msg Message shown when dieing.
 482  */
 483 function wfDebugDieBacktrace( $msg = '' ) {
 484         global $wgCommandLineMode;
 485
 486         if ( function_exists( 'debug_backtrace' ) ) {
 487                 if ( $wgCommandLineMode ) {
 488                         $msg .= "\nBacktrace:\n";
 489                 } else {
 490                         $msg .= "\n<p>Backtrace:</p>\n<ul>\n";
 491                 }
 492                 $backtrace = debug_backtrace();
 493                 foreach( $backtrace as $call ) {
 494                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 495                         $file = $f[count($f)-1];
 496                         if ( $wgCommandLineMode ) {
 497                                 $msg .= "$file line {$call['line']} calls ";
 498                         } else {
 499                                 $msg .= '<li>' . $file . ' line ' . $call['line'] . ' calls ';
 500                         }
 501                         if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 502                         $msg .= $call['function'] . '()';
 503
 504                         if ( $wgCommandLineMode ) {
 505                                 $msg .= "\n";
 506                         } else {
 507                                 $msg .= "</li>\n";
 508                         }
 509                 }
 510          }
 511          die( $msg );
 512 }
 513
 514
 515 /* Some generic result counters, pulled out of SearchEngine */
 516
 517
 518 /**
 519  * @todo document
 520  */
 521 function wfShowingResults( $offset, $limit ) {
 522         global $wgLang;
 523         return wfMsg( 'showingresults', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 524 }
 525
 526 /**
 527  * @todo document
 528  */
 529 function wfShowingResultsNum( $offset, $limit, $num ) {
 530         global $wgLang;
 531         return wfMsg( 'showingresultsnum', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 532 }
 533
 534 /**
 535  * @todo document
 536  */
 537 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 538         global $wgUser, $wgLang;
 539         $fmtLimit = $wgLang->formatNum( $limit );
 540         $prev = wfMsg( 'prevn', $fmtLimit );
 541         $next = wfMsg( 'nextn', $fmtLimit );
 542
 543         if( is_object( $link ) ) {
 544                 $title =& $link;
 545         } else {
 546                 $title =& Title::newFromText( $link );
 547                 if( is_null( $title ) ) {
 548                         return false;
 549                 }
 550         }
 551
 552         $sk = $wgUser->getSkin();
 553         if ( 0 != $offset ) {
 554                 $po = $offset - $limit;
 555                 if ( $po < 0 ) { $po = 0; }
 556                 $q = "limit={$limit}&offset={$po}";
 557                 if ( '' != $query ) { $q .= '&'.$query; }
 558                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$prev}</a>";
 559         } else { $plink = $prev; }
 560
 561         $no = $offset + $limit;
 562         $q = 'limit='.$limit.'&offset='.$no;
 563         if ( '' != $query ) { $q .= '&'.$query; }
 564
 565         if ( $atend ) {
 566                 $nlink = $next;
 567         } else {
 568                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$next}</a>";
 569         }
 570         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 571           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 572           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 573           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 574           wfNumLink( $offset, 500, $title, $query );
 575
 576         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 577 }
 578
 579 /**
 580  * @todo document
 581  */
 582 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 583         global $wgUser, $wgLang;
 584         if ( '' == $query ) { $q = ''; }
 585         else { $q = $query.'&'; }
 586         $q .= 'limit='.$limit.'&offset='.$offset;
 587
 588         $fmtLimit = $wgLang->formatNum( $limit );
 589         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$fmtLimit}</a>";
 590         return $s;
 591 }
 592
 593 /**
 594  * @todo document
 595  * @todo FIXME: we may want to blacklist some broken browsers
 596  *
 597  * @return bool Whereas client accept gzip compression
 598  */
 599 function wfClientAcceptsGzip() {
 600         global $wgUseGzip;
 601         if( $wgUseGzip ) {
 602                 # FIXME: we may want to blacklist some broken browsers
 603                 if( preg_match(
 604                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 605                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 606                         $m ) ) {
 607                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 608                         wfDebug( " accepts gzip\n" );
 609                         return true;
 610                 }
 611         }
 612         return false;
 613 }
 614
 615 /**
 616  * Yay, more global functions!
 617  */
 618 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 619         global $wgRequest;
 620         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 621 }
 622
 623 /**
 624  * Escapes the given text so that it may be output using addWikiText()
 625  * without any linking, formatting, etc. making its way through. This
 626  * is achieved by substituting certain characters with HTML entities.
 627  * As required by the callers, <nowiki> is not used. It currently does
 628  * not filter out characters which have special meaning only at the
 629  * start of a line, such as "*".
 630  *
 631  * @param string $text Text to be escaped
 632  */
 633 function wfEscapeWikiText( $text ) {
 634         $text = str_replace(
 635                 array( '[',             '|',      "'",     'ISBN '        , '://'         , "\n=", '{{' ),
 636                 array( '&#91;', '&#124;', '&#39;', 'ISBN&#32;', '&#58;//' , "\n&#61;", '&#123;&#123;' ),
 637                 htmlspecialchars($text) );
 638         return $text;
 639 }
 640
 641 /**
 642  * @todo document
 643  */
 644 function wfQuotedPrintable( $string, $charset = '' ) {
 645         # Probably incomplete; see RFC 2045
 646         if( empty( $charset ) ) {
 647                 global $wgInputEncoding;
 648                 $charset = $wgInputEncoding;
 649         }
 650         $charset = strtoupper( $charset );
 651         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 652
 653         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 654         $replace = $illegal . '\t ?_';
 655         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 656         $out = "=?$charset?Q?";
 657         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 658         $out .= '?=';
 659         return $out;
 660 }
 661
 662 /**
 663  * @todo document
 664  * @return float
 665  */
 666 function wfTime() {
 667         $st = explode( ' ', microtime() );
 668         return (float)$st[0] + (float)$st[1];
 669 }
 670
 671 /**
 672  * Changes the first character to an HTML entity
 673  */
 674 function wfHtmlEscapeFirst( $text ) {
 675         $ord = ord($text);
 676         $newText = substr($text, 1);
 677         return "&#$ord;$newText";
 678 }
 679
 680 /**
 681  * Sets dest to source and returns the original value of dest
 682  * If source is NULL, it just returns the value, it doesn't set the variable
 683  */
 684 function wfSetVar( &$dest, $source ) {
 685         $temp = $dest;
 686         if ( !is_null( $source ) ) {
 687                 $dest = $source;
 688         }
 689         return $temp;
 690 }
 691
 692 /**
 693  * As for wfSetVar except setting a bit
 694  */
 695 function wfSetBit( &$dest, $bit, $state = true ) {
 696         $temp = (bool)($dest & $bit );
 697         if ( !is_null( $state ) ) {
 698                 if ( $state ) {
 699                         $dest |= $bit;
 700                 } else {
 701                         $dest &= ~$bit;
 702                 }
 703         }
 704         return $temp;
 705 }
 706
 707 /**
 708  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 709  * "days=7&limit=100". Options in the first array override options in the second.
 710  * Options set to "" will not be output.
 711  */
 712 function wfArrayToCGI( $array1, $array2 = NULL )
 713 {
 714         if ( !is_null( $array2 ) ) {
 715                 $array1 = $array1 + $array2;
 716         }
 717
 718         $cgi = '';
 719         foreach ( $array1 as $key => $value ) {
 720                 if ( '' !== $value ) {
 721                         if ( '' != $cgi ) {
 722                                 $cgi .= '&';
 723                         }
 724                         $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 725                 }
 726         }
 727         return $cgi;
 728 }
 729
 730 /**
 731  * This is obsolete, use SquidUpdate::purge()
 732  * @deprecated
 733  */
 734 function wfPurgeSquidServers ($urlArr) {
 735         SquidUpdate::purge( $urlArr );
 736 }
 737
 738 /**
 739  * Windows-compatible version of escapeshellarg()
 740  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
 741  * function puts single quotes in regardless of OS
 742  */
 743 function wfEscapeShellArg( ) {
 744         $args = func_get_args();
 745         $first = true;
 746         $retVal = '';
 747         foreach ( $args as $arg ) {
 748                 if ( !$first ) {
 749                         $retVal .= ' ';
 750                 } else {
 751                         $first = false;
 752                 }
 753
 754                 if ( wfIsWindows() ) {
 755                         $retVal .= '"' . str_replace( '"','\"', $arg ) . '"';
 756                 } else {
 757                         $retVal .= escapeshellarg( $arg );
 758                 }
 759         }
 760         return $retVal;
 761 }
 762
 763 /**
 764  * wfMerge attempts to merge differences between three texts.
 765  * Returns true for a clean merge and false for failure or a conflict.
 766  */
 767 function wfMerge( $old, $mine, $yours, &$result ){
 768         global $wgDiff3;
 769
 770         # This check may also protect against code injection in
 771         # case of broken installations.
 772         if(! file_exists( $wgDiff3 ) ){
 773                 return false;
 774         }
 775
 776         # Make temporary files
 777         $td = '/tmp/';
 778         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
 779         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
 780         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
 781
 782         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
 783         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
 784         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
 785
 786         # Check for a conflict
 787         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
 788           wfEscapeShellArg( $mytextName ) . ' ' .
 789           wfEscapeShellArg( $oldtextName ) . ' ' .
 790           wfEscapeShellArg( $yourtextName );
 791         $handle = popen( $cmd, 'r' );
 792
 793         if( fgets( $handle ) ){
 794                 $conflict = true;
 795         } else {
 796                 $conflict = false;
 797         }
 798         pclose( $handle );
 799
 800         # Merge differences
 801         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
 802           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
 803         $handle = popen( $cmd, 'r' );
 804         $result = '';
 805         do {
 806                 $data = fread( $handle, 8192 );
 807                 if ( strlen( $data ) == 0 ) {
 808                         break;
 809                 }
 810                 $result .= $data;
 811         } while ( true );
 812         pclose( $handle );
 813         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
 814         return ! $conflict;
 815 }
 816
 817 /**
 818  * @todo document
 819  */
 820 function wfVarDump( $var ) {
 821         global $wgOut;
 822         $s = str_replace("\n","<br>\n", var_export( $var, true ) . "\n");
 823         if ( headers_sent() || !@is_object( $wgOut ) ) {
 824                 print $s;
 825         } else {
 826                 $wgOut->addHTML( $s );
 827         }
 828 }
 829
 830 /**
 831  * Provide a simple HTTP error.
 832  */
 833 function wfHttpError( $code, $label, $desc ) {
 834         global $wgOut;
 835         $wgOut->disable();
 836         header( "HTTP/1.0 $code $label" );
 837         header( "Status: $code $label" );
 838         $wgOut->sendCacheControl();
 839
 840         # Don't send content if it's a HEAD request.
 841         if( $_SERVER['REQUEST_METHOD'] == 'HEAD' ) {
 842                 header( 'Content-type: text/plain' );
 843                 print "$desc\n";
 844         }
 845 }
 846
 847 /**
 848  * Converts an Accept-* header into an array mapping string values to quality
 849  * factors
 850  */
 851 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
 852         # No arg means accept anything (per HTTP spec)
 853         if( !$accept ) {
 854                 return array( $def => 1 );
 855         }
 856
 857         $prefs = array();
 858
 859         $parts = explode( ',', $accept );
 860
 861         foreach( $parts as $part ) {
 862                 # FIXME: doesn't deal with params like 'text/html; level=1'
 863                 @list( $value, $qpart ) = explode( ';', $part );
 864                 if( !isset( $qpart ) ) {
 865                         $prefs[$value] = 1;
 866                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
 867                         $prefs[$value] = $match[1];
 868                 }
 869         }
 870
 871         return $prefs;
 872 }
 873
 874 /**
 875  * Checks if a given MIME type matches any of the keys in the given
 876  * array. Basic wildcards are accepted in the array keys.
 877  *
 878  * Returns the matching MIME type (or wildcard) if a match, otherwise
 879  * NULL if no match.
 880  *
 881  * @param string $type
 882  * @param array $avail
 883  * @return string
 884  * @access private
 885  */
 886 function mimeTypeMatch( $type, $avail ) {
 887         if( array_key_exists($type, $avail) ) {
 888                 return $type;
 889         } else {
 890                 $parts = explode( '/', $type );
 891                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
 892                         return $parts[0] . '/*';
 893                 } elseif( array_key_exists( '*/*', $avail ) ) {
 894                         return '*/*';
 895                 } else {
 896                         return NULL;
 897                 }
 898         }
 899 }
 900
 901 /**
 902  * Returns the 'best' match between a client's requested internet media types
 903  * and the server's list of available types. Each list should be an associative
 904  * array of type to preference (preference is a float between 0.0 and 1.0).
 905  * Wildcards in the types are acceptable.
 906  *
 907  * @param array $cprefs Client's acceptable type list
 908  * @param array $sprefs Server's offered types
 909  * @return string
 910  *
 911  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
 912  * XXX: generalize to negotiate other stuff
 913  */
 914 function wfNegotiateType( $cprefs, $sprefs ) {
 915         $combine = array();
 916
 917         foreach( array_keys($sprefs) as $type ) {
 918                 $parts = explode( '/', $type );
 919                 if( $parts[1] != '*' ) {
 920                         $ckey = mimeTypeMatch( $type, $cprefs );
 921                         if( $ckey ) {
 922                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
 923                         }
 924                 }
 925         }
 926
 927         foreach( array_keys( $cprefs ) as $type ) {
 928                 $parts = explode( '/', $type );
 929                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
 930                         $skey = mimeTypeMatch( $type, $sprefs );
 931                         if( $skey ) {
 932                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
 933                         }
 934                 }
 935         }
 936
 937         $bestq = 0;
 938         $besttype = NULL;
 939
 940         foreach( array_keys( $combine ) as $type ) {
 941                 if( $combine[$type] > $bestq ) {
 942                         $besttype = $type;
 943                         $bestq = $combine[$type];
 944                 }
 945         }
 946
 947         return $besttype;
 948 }
 949
 950 /**
 951  * Array lookup
 952  * Returns an array where the values in the first array are replaced by the
 953  * values in the second array with the corresponding keys
 954  *
 955  * @return array
 956  */
 957 function wfArrayLookup( $a, $b ) {
 958         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 959 }
 960
 961 /**
 962  * Convenience function; returns MediaWiki timestamp for the present time.
 963  * @return string
 964  */
 965 function wfTimestampNow() {
 966         # return NOW
 967         return wfTimestamp( TS_MW, time() );
 968 }
 969
 970 /**
 971  * Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 972  */
 973 function wfInvertTimestamp( $ts ) {
 974         return strtr(
 975                 $ts,
 976                 '0123456789',
 977                 '9876543210'
 978         );
 979 }
 980
 981 /**
 982  * Reference-counted warning suppression
 983  */
 984 function wfSuppressWarnings( $end = false ) {
 985         static $suppressCount = 0;
 986         static $originalLevel = false;
 987
 988         if ( $end ) {
 989                 if ( $suppressCount ) {
 990                         $suppressCount --;
 991                         if ( !$suppressCount ) {
 992                                 error_reporting( $originalLevel );
 993                         }
 994                 }
 995         } else {
 996                 if ( !$suppressCount ) {
 997                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
 998                 }
 999                 $suppressCount++;
1000         }
1001 }
1002
1003 /**
1004  * Restore error level to previous value
1005  */
1006 function wfRestoreWarnings() {
1007         wfSuppressWarnings( true );
1008 }
1009
1010 # Autodetect, convert and provide timestamps of various types
1011
1012 /** Standard unix timestamp (number of seconds since 1 Jan 1970) */
1013 define('TS_UNIX',0);
1014 /** MediaWiki concatenated string timestamp (yyyymmddhhmmss) */
1015 define('TS_MW',1);
1016 /** Standard database timestamp (yyyy-mm-dd hh:mm:ss) */
1017 define('TS_DB',2);
1018
1019 /**
1020  * @todo document
1021  */
1022 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1023         if (preg_match("/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/",$ts,$da)) {
1024                 # TS_DB
1025                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1026                             (int)$da[2],(int)$da[3],(int)$da[1]);
1027         } elseif (preg_match("/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/",$ts,$da)) {
1028                 # TS_MW
1029                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1030                             (int)$da[2],(int)$da[3],(int)$da[1]);
1031         } elseif (preg_match("/^(\d{1,13})$/",$ts,$datearray)) {
1032                 # TS_UNIX
1033                 $uts=$ts;
1034         }
1035
1036         if ($ts==0)
1037                 $uts=time();
1038         switch($outputtype) {
1039         case TS_UNIX:
1040                 return $uts;
1041                 break;
1042         case TS_MW:
1043                 return gmdate( 'YmdHis', $uts );
1044                 break;
1045         case TS_DB:
1046                 return gmdate( 'Y-m-d H:i:s', $uts );
1047                 break;
1048         default:
1049                 return;
1050         }
1051 }
1052
1053 /**
1054  * Check where as the operating system is Windows
1055  *
1056  * @todo document
1057  * @return bool True if it's windows, False otherwise.
1058  */
1059 function wfIsWindows() {
1060         if (substr(php_uname(), 0, 7) == 'Windows') {
1061                 return true;
1062         } else {
1063                 return false;
1064         }
1065 }
1066
1067 ?>