includes/GlobalFunctions.php

   1 <?php
   2
   3 if ( !defined( 'MEDIAWIKI' ) ) {
   4         die( "This file is part of MediaWiki, it is not a valid entry point" );
   5 }
   6
   7 /**
   8  * Global functions used everywhere
   9  */
  10
  11 require_once dirname(__FILE__) . '/LogPage.php';
  12 require_once dirname(__FILE__) . '/normal/UtfNormalUtil.php';
  13 require_once dirname(__FILE__) . '/XmlFunctions.php';
  14
  15 /**
  16  * Compatibility functions
  17  *
  18  * We more or less support PHP 5.0.x and up.
  19  * Re-implementations of newer functions or functions in non-standard
  20  * PHP extensions may be included here.
  21  */
  22 if( !function_exists('iconv') ) {
  23         # iconv support is not in the default configuration and so may not be present.
  24         # Assume will only ever use utf-8 and iso-8859-1.
  25         # This will *not* work in all circumstances.
  26         function iconv( $from, $to, $string ) {
  27                 if(strcasecmp( $from, $to ) == 0) return $string;
  28                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  29                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  30                 return $string;
  31         }
  32 }
  33
  34 # UTF-8 substr function based on a PHP manual comment
  35 if ( !function_exists( 'mb_substr' ) ) {
  36         function mb_substr( $str, $start ) {
  37                 $ar = array();
  38                 preg_match_all( '/./us', $str, $ar );
  39
  40                 if( func_num_args() >= 3 ) {
  41                         $end = func_get_arg( 2 );
  42                         return join( '', array_slice( $ar[0], $start, $end ) );
  43                 } else {
  44                         return join( '', array_slice( $ar[0], $start ) );
  45                 }
  46         }
  47 }
  48
  49 if ( !function_exists( 'mb_strlen' ) ) {
  50         /**
  51          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
  52          * @param string $str
  53          * @param string $enc optional encoding; ignored
  54          * @return int
  55          */
  56         function mb_strlen( $str, $enc="" ) {
  57                 $counts = count_chars( $str );
  58                 $total = 0;
  59
  60                 // Count ASCII bytes
  61                 for( $i = 0; $i < 0x80; $i++ ) {
  62                         $total += $counts[$i];
  63                 }
  64
  65                 // Count multibyte sequence heads
  66                 for( $i = 0xc0; $i < 0xff; $i++ ) {
  67                         $total += $counts[$i];
  68                 }
  69                 return $total;
  70         }
  71 }
  72
  73 if ( !function_exists( 'array_diff_key' ) ) {
  74         /**
  75          * Exists in PHP 5.1.0+
  76          * Not quite compatible, two-argument version only
  77          * Null values will cause problems due to this use of isset()
  78          */
  79         function array_diff_key( $left, $right ) {
  80                 $result = $left;
  81                 foreach ( $left as $key => $unused ) {
  82                         if ( isset( $right[$key] ) ) {
  83                                 unset( $result[$key] );
  84                         }
  85                 }
  86                 return $result;
  87         }
  88 }
  89
  90 /**
  91  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  92  */
  93 function wfArrayDiff2( $a, $b ) {
  94         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  95 }
  96 function wfArrayDiff2_cmp( $a, $b ) {
  97         if ( !is_array( $a ) ) {
  98                 return strcmp( $a, $b );
  99         } elseif ( count( $a ) !== count( $b ) ) {
 100                 return count( $a ) < count( $b ) ? -1 : 1;
 101         } else {
 102                 reset( $a );
 103                 reset( $b );
 104                 while( ( list( $keyA, $valueA ) = each( $a ) ) && ( list( $keyB, $valueB ) = each( $b ) ) ) {
 105                         $cmp = strcmp( $valueA, $valueB );
 106                         if ( $cmp !== 0 ) {
 107                                 return $cmp;
 108                         }
 109                 }
 110                 return 0;
 111         }
 112 }
 113
 114 /**
 115  * Wrapper for clone(), for compatibility with PHP4-friendly extensions.
 116  * PHP 5 won't let you declare a 'clone' function, even conditionally,
 117  * so it has to be a wrapper with a different name.
 118  */
 119 function wfClone( $object ) {
 120         return clone( $object );
 121 }
 122
 123 /**
 124  * Seed Mersenne Twister
 125  * No-op for compatibility; only necessary in PHP < 4.2.0
 126  */
 127 function wfSeedRandom() {
 128         /* No-op */
 129 }
 130
 131 /**
 132  * Get a random decimal value between 0 and 1, in a way
 133  * not likely to give duplicate values for any realistic
 134  * number of articles.
 135  *
 136  * @return string
 137  */
 138 function wfRandom() {
 139         # The maximum random value is "only" 2^31-1, so get two random
 140         # values to reduce the chance of dupes
 141         $max = mt_getrandmax() + 1;
 142         $rand = number_format( (mt_rand() * $max + mt_rand())
 143                 / $max / $max, 12, '.', '' );
 144         return $rand;
 145 }
 146
 147 /**
 148  * We want / and : to be included as literal characters in our title URLs.
 149  * %2F in the page titles seems to fatally break for some reason.
 150  *
 151  * @param $s String:
 152  * @return string
 153 */
 154 function wfUrlencode ( $s ) {
 155         $s = urlencode( $s );
 156         $s = preg_replace( '/%3[Aa]/', ':', $s );
 157         $s = preg_replace( '/%2[Ff]/', '/', $s );
 158
 159         return $s;
 160 }
 161
 162 /**
 163  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 164  * In normal operation this is a NOP.
 165  *
 166  * Controlling globals:
 167  * $wgDebugLogFile - points to the log file
 168  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 169  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 170  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 171  *
 172  * @param $text String
 173  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 174  */
 175 function wfDebug( $text, $logonly = false ) {
 176         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 177         static $recursion = 0;
 178
 179         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 180         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 181                 return;
 182         }
 183
 184         if ( $wgDebugComments && !$logonly ) {
 185                 if ( !isset( $wgOut ) ) {
 186                         return;
 187                 }
 188                 if ( !StubObject::isRealObject( $wgOut ) ) {
 189                         if ( $recursion ) {
 190                                 return;
 191                         }
 192                         $recursion++;
 193                         $wgOut->_unstub();
 194                         $recursion--;
 195                 }
 196                 $wgOut->debug( $text );
 197         }
 198         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 199                 # Strip unprintables; they can switch terminal modes when binary data
 200                 # gets dumped, which is pretty annoying.
 201                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 202                 wfErrorLog( $text, $wgDebugLogFile );
 203         }
 204 }
 205
 206 /**
 207  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 208  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 209  *
 210  * @param $logGroup String
 211  * @param $text String
 212  * @param $public Bool: whether to log the event in the public log if no private
 213  *                     log file is specified, (default true)
 214  */
 215 function wfDebugLog( $logGroup, $text, $public = true ) {
 216         global $wgDebugLogGroups;
 217         if( $text{strlen( $text ) - 1} != "\n" ) $text .= "\n";
 218         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 219                 $time = wfTimestamp( TS_DB );
 220                 $wiki = wfWikiID();
 221                 wfErrorLog( "$time $wiki: $text", $wgDebugLogGroups[$logGroup] );
 222         } else if ( $public === true ) {
 223                 wfDebug( $text, true );
 224         }
 225 }
 226
 227 /**
 228  * Log for database errors
 229  * @param $text String: database error message.
 230  */
 231 function wfLogDBError( $text ) {
 232         global $wgDBerrorLog, $wgDBname;
 233         if ( $wgDBerrorLog ) {
 234                 $host = trim(`hostname`);
 235                 $text = date('D M j G:i:s T Y') . "\t$host\t$wgDBname\t$text";
 236                 wfErrorLog( $text, $wgDBerrorLog );
 237         }
 238 }
 239
 240 /**
 241  * Log to a file without getting "file size exceeded" signals
 242  */
 243 function wfErrorLog( $text, $file ) {
 244         wfSuppressWarnings();
 245         $exists = file_exists( $file );
 246         $size = $exists ? filesize( $file ) : false;
 247         if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 248                 error_log( $text, 3, $file );
 249         }
 250         wfRestoreWarnings();
 251 }
 252
 253 /**
 254  * @todo document
 255  */
 256 function wfLogProfilingData() {
 257         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 258         global $wgProfiler, $wgUser;
 259         if ( !isset( $wgProfiler ) )
 260                 return;
 261
 262         $now = wfTime();
 263         $elapsed = $now - $wgRequestTime;
 264         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 265         $forward = '';
 266         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 267                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 268         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 269                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 270         if( !empty( $_SERVER['HTTP_FROM'] ) )
 271                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 272         if( $forward )
 273                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 274         // Don't unstub $wgUser at this late stage just for statistics purposes
 275         if( StubObject::isRealObject($wgUser) && $wgUser->isAnon() )
 276                 $forward .= ' anon';
 277         $log = sprintf( "%s\t%04.3f\t%s\n",
 278           gmdate( 'YmdHis' ), $elapsed,
 279           urldecode( $wgRequest->getRequestURL() . $forward ) );
 280         if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 281                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 282         }
 283 }
 284
 285 /**
 286  * Check if the wiki read-only lock file is present. This can be used to lock
 287  * off editing functions, but doesn't guarantee that the database will not be
 288  * modified.
 289  * @return bool
 290  */
 291 function wfReadOnly() {
 292         global $wgReadOnlyFile, $wgReadOnly;
 293
 294         if ( !is_null( $wgReadOnly ) ) {
 295                 return (bool)$wgReadOnly;
 296         }
 297         if ( '' == $wgReadOnlyFile ) {
 298                 return false;
 299         }
 300         // Set $wgReadOnly for faster access next time
 301         if ( is_file( $wgReadOnlyFile ) ) {
 302                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 303         } else {
 304                 $wgReadOnly = false;
 305         }
 306         return (bool)$wgReadOnly;
 307 }
 308
 309 function wfReadOnlyReason() {
 310         global $wgReadOnly;
 311         wfReadOnly();
 312         return $wgReadOnly;
 313 }
 314
 315 /**
 316  * Get a message from anywhere, for the current user language.
 317  *
 318  * Use wfMsgForContent() instead if the message should NOT
 319  * change depending on the user preferences.
 320  *
 321  * @param $key String: lookup key for the message, usually
 322  *    defined in languages/Language.php
 323  *
 324  * This function also takes extra optional parameters (not
 325  * shown in the function definition), which can by used to
 326  * insert variable text into the predefined message.
 327  */
 328 function wfMsg( $key ) {
 329         $args = func_get_args();
 330         array_shift( $args );
 331         return wfMsgReal( $key, $args, true );
 332 }
 333
 334 /**
 335  * Same as above except doesn't transform the message
 336  */
 337 function wfMsgNoTrans( $key ) {
 338         $args = func_get_args();
 339         array_shift( $args );
 340         return wfMsgReal( $key, $args, true, false, false );
 341 }
 342
 343 /**
 344  * Get a message from anywhere, for the current global language
 345  * set with $wgLanguageCode.
 346  *
 347  * Use this if the message should NOT change  dependent on the
 348  * language set in the user's preferences. This is the case for
 349  * most text written into logs, as well as link targets (such as
 350  * the name of the copyright policy page). Link titles, on the
 351  * other hand, should be shown in the UI language.
 352  *
 353  * Note that MediaWiki allows users to change the user interface
 354  * language in their preferences, but a single installation
 355  * typically only contains content in one language.
 356  *
 357  * Be wary of this distinction: If you use wfMsg() where you should
 358  * use wfMsgForContent(), a user of the software may have to
 359  * customize over 70 messages in order to, e.g., fix a link in every
 360  * possible language.
 361  *
 362  * @param $key String: lookup key for the message, usually
 363  *    defined in languages/Language.php
 364  */
 365 function wfMsgForContent( $key ) {
 366         global $wgForceUIMsgAsContentMsg;
 367         $args = func_get_args();
 368         array_shift( $args );
 369         $forcontent = true;
 370         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 371                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 372                 $forcontent = false;
 373         return wfMsgReal( $key, $args, true, $forcontent );
 374 }
 375
 376 /**
 377  * Same as above except doesn't transform the message
 378  */
 379 function wfMsgForContentNoTrans( $key ) {
 380         global $wgForceUIMsgAsContentMsg;
 381         $args = func_get_args();
 382         array_shift( $args );
 383         $forcontent = true;
 384         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 385                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 386                 $forcontent = false;
 387         return wfMsgReal( $key, $args, true, $forcontent, false );
 388 }
 389
 390 /**
 391  * Get a message from the language file, for the UI elements
 392  */
 393 function wfMsgNoDB( $key ) {
 394         $args = func_get_args();
 395         array_shift( $args );
 396         return wfMsgReal( $key, $args, false );
 397 }
 398
 399 /**
 400  * Get a message from the language file, for the content
 401  */
 402 function wfMsgNoDBForContent( $key ) {
 403         global $wgForceUIMsgAsContentMsg;
 404         $args = func_get_args();
 405         array_shift( $args );
 406         $forcontent = true;
 407         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 408                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 409                 $forcontent = false;
 410         return wfMsgReal( $key, $args, false, $forcontent );
 411 }
 412
 413
 414 /**
 415  * Really get a message
 416  * @param $key String: key to get.
 417  * @param $args
 418  * @param $useDB Boolean
 419  * @param $transform Boolean: Whether or not to transform the message.
 420  * @param $forContent Boolean
 421  * @return String: the requested message.
 422  */
 423 function wfMsgReal( $key, $args, $useDB = true, $forContent=false, $transform = true ) {
 424         wfProfileIn( __METHOD__ );
 425         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 426         $message = wfMsgReplaceArgs( $message, $args );
 427         wfProfileOut( __METHOD__ );
 428         return $message;
 429 }
 430
 431 /**
 432  * This function provides the message source for messages to be edited which are *not* stored in the database.
 433  * @param $key String:
 434  */
 435 function wfMsgWeirdKey ( $key ) {
 436         $source = wfMsgGetKey( $key, false, true, false );
 437         if ( wfEmptyMsg( $key, $source ) )
 438                 return "";
 439         else
 440                 return $source;
 441 }
 442
 443 /**
 444  * Fetch a message string value, but don't replace any keys yet.
 445  * @param string $key
 446  * @param bool $useDB
 447  * @param string $langcode Code of the language to get the message for, or
 448  *                         behaves as a content language switch if it is a
 449  *                         boolean.
 450  * @return string
 451  * @private
 452  */
 453 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 454         global $wgParser, $wgContLang, $wgMessageCache, $wgLang;
 455
 456         # If $wgMessageCache isn't initialised yet, try to return something sensible.
 457         if( is_object( $wgMessageCache ) ) {
 458                 $message = $wgMessageCache->get( $key, $useDB, $langCode );
 459                 if ( $transform ) {
 460                         $message = $wgMessageCache->transform( $message );
 461                 }
 462         } else {
 463                 if( $langCode === true ) {
 464                         $lang = &$wgContLang;
 465                 } elseif( $langCode === false ) {
 466                         $lang = &$wgLang;
 467                 } else {
 468                         $validCodes = array_keys( Language::getLanguageNames() );
 469                         if( in_array( $langCode, $validCodes ) ) {
 470                                 # $langcode corresponds to a valid language.
 471                                 $lang = Language::factory( $langCode );
 472                         } else {
 473                                 # $langcode is a string, but not a valid language code; use content language.
 474                                 $lang =& $wgContLang;
 475                                 wfDebug( 'Invalid language code passed to wfMsgGetKey, falling back to content language.' );
 476                         }
 477                 }
 478
 479                 # MessageCache::get() does this already, Language::getMessage() doesn't
 480                 # ISSUE: Should we try to handle "message/lang" here too?
 481                 $key = str_replace( ' ' , '_' , $wgContLang->lcfirst( $key ) );
 482
 483                 if( is_object( $lang ) ) {
 484                         $message = $lang->getMessage( $key );
 485                 } else {
 486                         $message = false;
 487                 }
 488         }
 489
 490         return $message;
 491 }
 492
 493 /**
 494  * Replace message parameter keys on the given formatted output.
 495  *
 496  * @param string $message
 497  * @param array $args
 498  * @return string
 499  * @private
 500  */
 501 function wfMsgReplaceArgs( $message, $args ) {
 502         # Fix windows line-endings
 503         # Some messages are split with explode("\n", $msg)
 504         $message = str_replace( "\r", '', $message );
 505
 506         // Replace arguments
 507         if ( count( $args ) ) {
 508                 if ( is_array( $args[0] ) ) {
 509                         $args = array_values( $args[0] );
 510                 }
 511                 $replacementKeys = array();
 512                 foreach( $args as $n => $param ) {
 513                         $replacementKeys['$' . ($n + 1)] = $param;
 514                 }
 515                 $message = strtr( $message, $replacementKeys );
 516         }
 517
 518         return $message;
 519 }
 520
 521 /**
 522  * Return an HTML-escaped version of a message.
 523  * Parameter replacements, if any, are done *after* the HTML-escaping,
 524  * so parameters may contain HTML (eg links or form controls). Be sure
 525  * to pre-escape them if you really do want plaintext, or just wrap
 526  * the whole thing in htmlspecialchars().
 527  *
 528  * @param string $key
 529  * @param string ... parameters
 530  * @return string
 531  */
 532 function wfMsgHtml( $key ) {
 533         $args = func_get_args();
 534         array_shift( $args );
 535         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 536 }
 537
 538 /**
 539  * Return an HTML version of message
 540  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 541  * so parameters may contain HTML (eg links or form controls). Be sure
 542  * to pre-escape them if you really do want plaintext, or just wrap
 543  * the whole thing in htmlspecialchars().
 544  *
 545  * @param string $key
 546  * @param string ... parameters
 547  * @return string
 548  */
 549 function wfMsgWikiHtml( $key ) {
 550         global $wgOut;
 551         $args = func_get_args();
 552         array_shift( $args );
 553         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 554 }
 555
 556 /**
 557  * Returns message in the requested format
 558  * @param string $key Key of the message
 559  * @param array $options Processing rules:
 560  *  <i>parse</i>: parses wikitext to html
 561  *  <i>parseinline</i>: parses wikitext to html and removes the surrounding p's added by parser or tidy
 562  *  <i>escape</i>: filters message through htmlspecialchars
 563  *  <i>escapenoentities</i>: same, but allows entity references like &nbsp; through
 564  *  <i>replaceafter</i>: parameters are substituted after parsing or escaping
 565  *  <i>parsemag</i>: transform the message using magic phrases
 566  *  <i>content</i>: fetch message for content language instead of interface
 567  *  <i>language</i>: language code to fetch message for (overriden by <i>content</i>), its behaviour
 568  *                   with parser, parseinline and parsemag is undefined.
 569  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 570  */
 571 function wfMsgExt( $key, $options ) {
 572         global $wgOut, $wgParser;
 573
 574         $args = func_get_args();
 575         array_shift( $args );
 576         array_shift( $args );
 577
 578         if( !is_array($options) ) {
 579                 $options = array($options);
 580         }
 581
 582         if( in_array('content', $options) ) {
 583                 $forContent = true;
 584                 $langCode = true;
 585         } elseif( array_key_exists('language', $options) ) {
 586                 $forContent = false;
 587                 $langCode = $options['language'];
 588                 $validCodes = array_keys( Language::getLanguageNames() );
 589                 if( !in_array($options['language'], $validCodes) ) {
 590                         # Fallback to en, instead of whatever interface language we might have
 591                         $langCode = 'en';
 592                 }
 593         } else {
 594                 $forContent = false;
 595                 $langCode = false;
 596         }
 597
 598         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 599
 600         if( !in_array('replaceafter', $options) ) {
 601                 $string = wfMsgReplaceArgs( $string, $args );
 602         }
 603
 604         if( in_array('parse', $options) ) {
 605                 $string = $wgOut->parse( $string, true, !$forContent );
 606         } elseif ( in_array('parseinline', $options) ) {
 607                 $string = $wgOut->parse( $string, true, !$forContent );
 608                 $m = array();
 609                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 610                         $string = $m[1];
 611                 }
 612         } elseif ( in_array('parsemag', $options) ) {
 613                 global $wgMessageCache;
 614                 if ( isset( $wgMessageCache ) ) {
 615                         $string = $wgMessageCache->transform( $string, !$forContent );
 616                 }
 617         }
 618
 619         if ( in_array('escape', $options) ) {
 620                 $string = htmlspecialchars ( $string );
 621         } elseif ( in_array( 'escapenoentities', $options ) ) {
 622                 $string = htmlspecialchars( $string );
 623                 $string = str_replace( '&amp;', '&', $string );
 624                 $string = Sanitizer::normalizeCharReferences( $string );
 625         }
 626
 627         if( in_array('replaceafter', $options) ) {
 628                 $string = wfMsgReplaceArgs( $string, $args );
 629         }
 630
 631         return $string;
 632 }
 633
 634
 635 /**
 636  * Just like exit() but makes a note of it.
 637  * Commits open transactions except if the error parameter is set
 638  *
 639  * @deprecated Please return control to the caller or throw an exception
 640  */
 641 function wfAbruptExit( $error = false ){
 642         static $called = false;
 643         if ( $called ){
 644                 exit( -1 );
 645         }
 646         $called = true;
 647
 648         $bt = wfDebugBacktrace();
 649         if( $bt ) {
 650                 for($i = 0; $i < count($bt) ; $i++){
 651                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 652                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 653                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 654                 }
 655         } else {
 656                 wfDebug('WARNING: Abrupt exit\n');
 657         }
 658
 659         wfLogProfilingData();
 660
 661         if ( !$error ) {
 662                 wfGetLB()->closeAll();
 663         }
 664         exit( -1 );
 665 }
 666
 667 /**
 668  * @deprecated Please return control the caller or throw an exception
 669  */
 670 function wfErrorExit() {
 671         wfAbruptExit( true );
 672 }
 673
 674 /**
 675  * Print a simple message and die, returning nonzero to the shell if any.
 676  * Plain die() fails to return nonzero to the shell if you pass a string.
 677  * @param string $msg
 678  */
 679 function wfDie( $msg='' ) {
 680         echo $msg;
 681         die( 1 );
 682 }
 683
 684 /**
 685  * Throw a debugging exception. This function previously once exited the process,
 686  * but now throws an exception instead, with similar results.
 687  *
 688  * @param string $msg Message shown when dieing.
 689  */
 690 function wfDebugDieBacktrace( $msg = '' ) {
 691         throw new MWException( $msg );
 692 }
 693
 694 /**
 695  * Fetch server name for use in error reporting etc.
 696  * Use real server name if available, so we know which machine
 697  * in a server farm generated the current page.
 698  * @return string
 699  */
 700 function wfHostname() {
 701         if ( function_exists( 'posix_uname' ) ) {
 702                 // This function not present on Windows
 703                 $uname = @posix_uname();
 704         } else {
 705                 $uname = false;
 706         }
 707         if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 708                 return $uname['nodename'];
 709         } else {
 710                 # This may be a virtual server.
 711                 return $_SERVER['SERVER_NAME'];
 712         }
 713 }
 714
 715         /**
 716          * Returns a HTML comment with the elapsed time since request.
 717          * This method has no side effects.
 718          * @return string
 719          */
 720         function wfReportTime() {
 721                 global $wgRequestTime, $wgShowHostnames;
 722
 723                 $now = wfTime();
 724                 $elapsed = $now - $wgRequestTime;
 725
 726                 return $wgShowHostnames
 727                         ? sprintf( "<!-- Served by %s in %01.3f secs. -->", wfHostname(), $elapsed )
 728                         : sprintf( "<!-- Served in %01.3f secs. -->", $elapsed );
 729         }
 730
 731 /**
 732  * Safety wrapper for debug_backtrace().
 733  *
 734  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 735  * murky circumstances, which may be triggered in part by stub objects
 736  * or other fancy talkin'.
 737  *
 738  * Will return an empty array if Zend Optimizer is detected, otherwise
 739  * the output from debug_backtrace() (trimmed).
 740  *
 741  * @return array of backtrace information
 742  */
 743 function wfDebugBacktrace() {
 744         if( extension_loaded( 'Zend Optimizer' ) ) {
 745                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 746                 return array();
 747         } else {
 748                 return array_slice( debug_backtrace(), 1 );
 749         }
 750 }
 751
 752 function wfBacktrace() {
 753         global $wgCommandLineMode;
 754
 755         if ( $wgCommandLineMode ) {
 756                 $msg = '';
 757         } else {
 758                 $msg = "<ul>\n";
 759         }
 760         $backtrace = wfDebugBacktrace();
 761         foreach( $backtrace as $call ) {
 762                 if( isset( $call['file'] ) ) {
 763                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 764                         $file = $f[count($f)-1];
 765                 } else {
 766                         $file = '-';
 767                 }
 768                 if( isset( $call['line'] ) ) {
 769                         $line = $call['line'];
 770                 } else {
 771                         $line = '-';
 772                 }
 773                 if ( $wgCommandLineMode ) {
 774                         $msg .= "$file line $line calls ";
 775                 } else {
 776                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 777                 }
 778                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 779                 $msg .= $call['function'] . '()';
 780
 781                 if ( $wgCommandLineMode ) {
 782                         $msg .= "\n";
 783                 } else {
 784                         $msg .= "</li>\n";
 785                 }
 786         }
 787         if ( $wgCommandLineMode ) {
 788                 $msg .= "\n";
 789         } else {
 790                 $msg .= "</ul>\n";
 791         }
 792
 793         return $msg;
 794 }
 795
 796
 797 /* Some generic result counters, pulled out of SearchEngine */
 798
 799
 800 /**
 801  * @todo document
 802  */
 803 function wfShowingResults( $offset, $limit ) {
 804         global $wgLang;
 805         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 806 }
 807
 808 /**
 809  * @todo document
 810  */
 811 function wfShowingResultsNum( $offset, $limit, $num ) {
 812         global $wgLang;
 813         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 814 }
 815
 816 /**
 817  * @todo document
 818  */
 819 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 820         global $wgLang;
 821         $fmtLimit = $wgLang->formatNum( $limit );
 822         $prev = wfMsg( 'prevn', $fmtLimit );
 823         $next = wfMsg( 'nextn', $fmtLimit );
 824
 825         if( is_object( $link ) ) {
 826                 $title =& $link;
 827         } else {
 828                 $title = Title::newFromText( $link );
 829                 if( is_null( $title ) ) {
 830                         return false;
 831                 }
 832         }
 833
 834         if ( 0 != $offset ) {
 835                 $po = $offset - $limit;
 836                 if ( $po < 0 ) { $po = 0; }
 837                 $q = "limit={$limit}&offset={$po}";
 838                 if ( '' != $query ) { $q .= '&'.$query; }
 839                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
 840         } else { $plink = $prev; }
 841
 842         $no = $offset + $limit;
 843         $q = 'limit='.$limit.'&offset='.$no;
 844         if ( '' != $query ) { $q .= '&'.$query; }
 845
 846         if ( $atend ) {
 847                 $nlink = $next;
 848         } else {
 849                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
 850         }
 851         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 852           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 853           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 854           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 855           wfNumLink( $offset, 500, $title, $query );
 856
 857         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 858 }
 859
 860 /**
 861  * @todo document
 862  */
 863 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 864         global $wgLang;
 865         if ( '' == $query ) { $q = ''; }
 866         else { $q = $query.'&'; }
 867         $q .= 'limit='.$limit.'&offset='.$offset;
 868
 869         $fmtLimit = $wgLang->formatNum( $limit );
 870         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-numlink\">{$fmtLimit}</a>";
 871         return $s;
 872 }
 873
 874 /**
 875  * @todo document
 876  * @todo FIXME: we may want to blacklist some broken browsers
 877  *
 878  * @return bool Whereas client accept gzip compression
 879  */
 880 function wfClientAcceptsGzip() {
 881         global $wgUseGzip;
 882         if( $wgUseGzip ) {
 883                 # FIXME: we may want to blacklist some broken browsers
 884                 $m = array();
 885                 if( preg_match(
 886                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 887                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 888                         $m ) ) {
 889                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 890                         wfDebug( " accepts gzip\n" );
 891                         return true;
 892                 }
 893         }
 894         return false;
 895 }
 896
 897 /**
 898  * Obtain the offset and limit values from the request string;
 899  * used in special pages
 900  *
 901  * @param $deflimit Default limit if none supplied
 902  * @param $optionname Name of a user preference to check against
 903  * @return array
 904  *
 905  */
 906 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 907         global $wgRequest;
 908         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 909 }
 910
 911 /**
 912  * Escapes the given text so that it may be output using addWikiText()
 913  * without any linking, formatting, etc. making its way through. This
 914  * is achieved by substituting certain characters with HTML entities.
 915  * As required by the callers, <nowiki> is not used. It currently does
 916  * not filter out characters which have special meaning only at the
 917  * start of a line, such as "*".
 918  *
 919  * @param string $text Text to be escaped
 920  */
 921 function wfEscapeWikiText( $text ) {
 922         $text = str_replace(
 923                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
 924                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
 925                 htmlspecialchars($text) );
 926         return $text;
 927 }
 928
 929 /**
 930  * @todo document
 931  */
 932 function wfQuotedPrintable( $string, $charset = '' ) {
 933         # Probably incomplete; see RFC 2045
 934         if( empty( $charset ) ) {
 935                 global $wgInputEncoding;
 936                 $charset = $wgInputEncoding;
 937         }
 938         $charset = strtoupper( $charset );
 939         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 940
 941         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 942         $replace = $illegal . '\t ?_';
 943         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 944         $out = "=?$charset?Q?";
 945         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 946         $out .= '?=';
 947         return $out;
 948 }
 949
 950
 951 /**
 952  * @todo document
 953  * @return float
 954  */
 955 function wfTime() {
 956         return microtime(true);
 957 }
 958
 959 /**
 960  * Sets dest to source and returns the original value of dest
 961  * If source is NULL, it just returns the value, it doesn't set the variable
 962  */
 963 function wfSetVar( &$dest, $source ) {
 964         $temp = $dest;
 965         if ( !is_null( $source ) ) {
 966                 $dest = $source;
 967         }
 968         return $temp;
 969 }
 970
 971 /**
 972  * As for wfSetVar except setting a bit
 973  */
 974 function wfSetBit( &$dest, $bit, $state = true ) {
 975         $temp = (bool)($dest & $bit );
 976         if ( !is_null( $state ) ) {
 977                 if ( $state ) {
 978                         $dest |= $bit;
 979                 } else {
 980                         $dest &= ~$bit;
 981                 }
 982         }
 983         return $temp;
 984 }
 985
 986 /**
 987  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 988  * "days=7&limit=100". Options in the first array override options in the second.
 989  * Options set to "" will not be output.
 990  */
 991 function wfArrayToCGI( $array1, $array2 = NULL )
 992 {
 993         if ( !is_null( $array2 ) ) {
 994                 $array1 = $array1 + $array2;
 995         }
 996
 997         $cgi = '';
 998         foreach ( $array1 as $key => $value ) {
 999                 if ( '' !== $value ) {
1000                         if ( '' != $cgi ) {
1001                                 $cgi .= '&';
1002                         }
1003                         if(is_array($value))
1004                         {
1005                                 $firstTime = true;
1006                                 foreach($value as $v)
1007                                 {
1008                                         $cgi .= ($firstTime ? '' : '&') .
1009                                                 urlencode( $key . '[]' ) . '=' .
1010                                                 urlencode( $v );
1011                                         $firstTime = false;
1012                                 }
1013                         }
1014                         else
1015                                 $cgi .= urlencode( $key ) . '=' .
1016                                         urlencode( $value );
1017                 }
1018         }
1019         return $cgi;
1020 }
1021
1022 /**
1023  * Append a query string to an existing URL, which may or may not already
1024  * have query string parameters already. If so, they will be combined.
1025  *
1026  * @param string $url
1027  * @param string $query
1028  * @return string
1029  */
1030 function wfAppendQuery( $url, $query ) {
1031         if( $query != '' ) {
1032                 if( false === strpos( $url, '?' ) ) {
1033                         $url .= '?';
1034                 } else {
1035                         $url .= '&';
1036                 }
1037                 $url .= $query;
1038         }
1039         return $url;
1040 }
1041
1042 /**
1043  * Expand a potentially local URL to a fully-qualified URL.
1044  * Assumes $wgServer is correct. :)
1045  * @param string $url, either fully-qualified or a local path + query
1046  * @return string Fully-qualified URL
1047  */
1048 function wfExpandUrl( $url ) {
1049         if( substr( $url, 0, 1 ) == '/' ) {
1050                 global $wgServer;
1051                 return $wgServer . $url;
1052         } else {
1053                 return $url;
1054         }
1055 }
1056
1057 /**
1058  * This is obsolete, use SquidUpdate::purge()
1059  * @deprecated
1060  */
1061 function wfPurgeSquidServers ($urlArr) {
1062         SquidUpdate::purge( $urlArr );
1063 }
1064
1065 /**
1066  * Windows-compatible version of escapeshellarg()
1067  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1068  * function puts single quotes in regardless of OS
1069  */
1070 function wfEscapeShellArg( ) {
1071         $args = func_get_args();
1072         $first = true;
1073         $retVal = '';
1074         foreach ( $args as $arg ) {
1075                 if ( !$first ) {
1076                         $retVal .= ' ';
1077                 } else {
1078                         $first = false;
1079                 }
1080
1081                 if ( wfIsWindows() ) {
1082                         // Escaping for an MSVC-style command line parser
1083                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1084                         // Double the backslashes before any double quotes. Escape the double quotes.
1085                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1086                         $arg = '';
1087                         $delim = false;
1088                         foreach ( $tokens as $token ) {
1089                                 if ( $delim ) {
1090                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1091                                 } else {
1092                                         $arg .= $token;
1093                                 }
1094                                 $delim = !$delim;
1095                         }
1096                         // Double the backslashes before the end of the string, because
1097                         // we will soon add a quote
1098                         $m = array();
1099                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1100                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1101                         }
1102
1103                         // Add surrounding quotes
1104                         $retVal .= '"' . $arg . '"';
1105                 } else {
1106                         $retVal .= escapeshellarg( $arg );
1107                 }
1108         }
1109         return $retVal;
1110 }
1111
1112 /**
1113  * wfMerge attempts to merge differences between three texts.
1114  * Returns true for a clean merge and false for failure or a conflict.
1115  */
1116 function wfMerge( $old, $mine, $yours, &$result ){
1117         global $wgDiff3;
1118
1119         # This check may also protect against code injection in
1120         # case of broken installations.
1121         if(! file_exists( $wgDiff3 ) ){
1122                 wfDebug( "diff3 not found\n" );
1123                 return false;
1124         }
1125
1126         # Make temporary files
1127         $td = wfTempDir();
1128         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1129         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1130         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1131
1132         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1133         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1134         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1135
1136         # Check for a conflict
1137         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1138           wfEscapeShellArg( $mytextName ) . ' ' .
1139           wfEscapeShellArg( $oldtextName ) . ' ' .
1140           wfEscapeShellArg( $yourtextName );
1141         $handle = popen( $cmd, 'r' );
1142
1143         if( fgets( $handle, 1024 ) ){
1144                 $conflict = true;
1145         } else {
1146                 $conflict = false;
1147         }
1148         pclose( $handle );
1149
1150         # Merge differences
1151         $cmd = $wgDiff3 . ' -a -e --merge ' .
1152           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1153         $handle = popen( $cmd, 'r' );
1154         $result = '';
1155         do {
1156                 $data = fread( $handle, 8192 );
1157                 if ( strlen( $data ) == 0 ) {
1158                         break;
1159                 }
1160                 $result .= $data;
1161         } while ( true );
1162         pclose( $handle );
1163         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1164
1165         if ( $result === '' && $old !== '' && $conflict == false ) {
1166                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1167                 $conflict = true;
1168         }
1169         return ! $conflict;
1170 }
1171
1172 /**
1173  * @todo document
1174  */
1175 function wfVarDump( $var ) {
1176         global $wgOut;
1177         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1178         if ( headers_sent() || !@is_object( $wgOut ) ) {
1179                 print $s;
1180         } else {
1181                 $wgOut->addHTML( $s );
1182         }
1183 }
1184
1185 /**
1186  * Provide a simple HTTP error.
1187  */
1188 function wfHttpError( $code, $label, $desc ) {
1189         global $wgOut;
1190         $wgOut->disable();
1191         header( "HTTP/1.0 $code $label" );
1192         header( "Status: $code $label" );
1193         $wgOut->sendCacheControl();
1194
1195         header( 'Content-type: text/html; charset=utf-8' );
1196         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1197                 "<html><head><title>" .
1198                 htmlspecialchars( $label ) .
1199                 "</title></head><body><h1>" .
1200                 htmlspecialchars( $label ) .
1201                 "</h1><p>" .
1202                 nl2br( htmlspecialchars( $desc ) ) .
1203                 "</p></body></html>\n";
1204 }
1205
1206 /**
1207  * Clear away any user-level output buffers, discarding contents.
1208  *
1209  * Suitable for 'starting afresh', for instance when streaming
1210  * relatively large amounts of data without buffering, or wanting to
1211  * output image files without ob_gzhandler's compression.
1212  *
1213  * The optional $resetGzipEncoding parameter controls suppression of
1214  * the Content-Encoding header sent by ob_gzhandler; by default it
1215  * is left. See comments for wfClearOutputBuffers() for why it would
1216  * be used.
1217  *
1218  * Note that some PHP configuration options may add output buffer
1219  * layers which cannot be removed; these are left in place.
1220  *
1221  * @param bool $resetGzipEncoding
1222  */
1223 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1224         if( $resetGzipEncoding ) {
1225                 // Suppress Content-Encoding and Content-Length
1226                 // headers from 1.10+s wfOutputHandler
1227                 global $wgDisableOutputCompression;
1228                 $wgDisableOutputCompression = true;
1229         }
1230         while( $status = ob_get_status() ) {
1231                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1232                         // Probably from zlib.output_compression or other
1233                         // PHP-internal setting which can't be removed.
1234                         //
1235                         // Give up, and hope the result doesn't break
1236                         // output behavior.
1237                         break;
1238                 }
1239                 if( !ob_end_clean() ) {
1240                         // Could not remove output buffer handler; abort now
1241                         // to avoid getting in some kind of infinite loop.
1242                         break;
1243                 }
1244                 if( $resetGzipEncoding ) {
1245                         if( $status['name'] == 'ob_gzhandler' ) {
1246                                 // Reset the 'Content-Encoding' field set by this handler
1247                                 // so we can start fresh.
1248                                 header( 'Content-Encoding:' );
1249                         }
1250                 }
1251         }
1252 }
1253
1254 /**
1255  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1256  *
1257  * Clear away output buffers, but keep the Content-Encoding header
1258  * produced by ob_gzhandler, if any.
1259  *
1260  * This should be used for HTTP 304 responses, where you need to
1261  * preserve the Content-Encoding header of the real result, but
1262  * also need to suppress the output of ob_gzhandler to keep to spec
1263  * and avoid breaking Firefox in rare cases where the headers and
1264  * body are broken over two packets.
1265  */
1266 function wfClearOutputBuffers() {
1267         wfResetOutputBuffers( false );
1268 }
1269
1270 /**
1271  * Converts an Accept-* header into an array mapping string values to quality
1272  * factors
1273  */
1274 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1275         # No arg means accept anything (per HTTP spec)
1276         if( !$accept ) {
1277                 return array( $def => 1.0 );
1278         }
1279
1280         $prefs = array();
1281
1282         $parts = explode( ',', $accept );
1283
1284         foreach( $parts as $part ) {
1285                 # FIXME: doesn't deal with params like 'text/html; level=1'
1286                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1287                 $match = array();
1288                 if( !isset( $qpart ) ) {
1289                         $prefs[$value] = 1.0;
1290                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1291                         $prefs[$value] = floatval($match[1]);
1292                 }
1293         }
1294
1295         return $prefs;
1296 }
1297
1298 /**
1299  * Checks if a given MIME type matches any of the keys in the given
1300  * array. Basic wildcards are accepted in the array keys.
1301  *
1302  * Returns the matching MIME type (or wildcard) if a match, otherwise
1303  * NULL if no match.
1304  *
1305  * @param string $type
1306  * @param array $avail
1307  * @return string
1308  * @private
1309  */
1310 function mimeTypeMatch( $type, $avail ) {
1311         if( array_key_exists($type, $avail) ) {
1312                 return $type;
1313         } else {
1314                 $parts = explode( '/', $type );
1315                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1316                         return $parts[0] . '/*';
1317                 } elseif( array_key_exists( '*/*', $avail ) ) {
1318                         return '*/*';
1319                 } else {
1320                         return NULL;
1321                 }
1322         }
1323 }
1324
1325 /**
1326  * Returns the 'best' match between a client's requested internet media types
1327  * and the server's list of available types. Each list should be an associative
1328  * array of type to preference (preference is a float between 0.0 and 1.0).
1329  * Wildcards in the types are acceptable.
1330  *
1331  * @param array $cprefs Client's acceptable type list
1332  * @param array $sprefs Server's offered types
1333  * @return string
1334  *
1335  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1336  * XXX: generalize to negotiate other stuff
1337  */
1338 function wfNegotiateType( $cprefs, $sprefs ) {
1339         $combine = array();
1340
1341         foreach( array_keys($sprefs) as $type ) {
1342                 $parts = explode( '/', $type );
1343                 if( $parts[1] != '*' ) {
1344                         $ckey = mimeTypeMatch( $type, $cprefs );
1345                         if( $ckey ) {
1346                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1347                         }
1348                 }
1349         }
1350
1351         foreach( array_keys( $cprefs ) as $type ) {
1352                 $parts = explode( '/', $type );
1353                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1354                         $skey = mimeTypeMatch( $type, $sprefs );
1355                         if( $skey ) {
1356                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1357                         }
1358                 }
1359         }
1360
1361         $bestq = 0;
1362         $besttype = NULL;
1363
1364         foreach( array_keys( $combine ) as $type ) {
1365                 if( $combine[$type] > $bestq ) {
1366                         $besttype = $type;
1367                         $bestq = $combine[$type];
1368                 }
1369         }
1370
1371         return $besttype;
1372 }
1373
1374 /**
1375  * Array lookup
1376  * Returns an array where the values in the first array are replaced by the
1377  * values in the second array with the corresponding keys
1378  *
1379  * @return array
1380  */
1381 function wfArrayLookup( $a, $b ) {
1382         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1383 }
1384
1385 /**
1386  * Convenience function; returns MediaWiki timestamp for the present time.
1387  * @return string
1388  */
1389 function wfTimestampNow() {
1390         # return NOW
1391         return wfTimestamp( TS_MW, time() );
1392 }
1393
1394 /**
1395  * Reference-counted warning suppression
1396  */
1397 function wfSuppressWarnings( $end = false ) {
1398         static $suppressCount = 0;
1399         static $originalLevel = false;
1400
1401         if ( $end ) {
1402                 if ( $suppressCount ) {
1403                         --$suppressCount;
1404                         if ( !$suppressCount ) {
1405                                 error_reporting( $originalLevel );
1406                         }
1407                 }
1408         } else {
1409                 if ( !$suppressCount ) {
1410                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1411                 }
1412                 ++$suppressCount;
1413         }
1414 }
1415
1416 /**
1417  * Restore error level to previous value
1418  */
1419 function wfRestoreWarnings() {
1420         wfSuppressWarnings( true );
1421 }
1422
1423 # Autodetect, convert and provide timestamps of various types
1424
1425 /**
1426  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1427  */
1428 define('TS_UNIX', 0);
1429
1430 /**
1431  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1432  */
1433 define('TS_MW', 1);
1434
1435 /**
1436  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1437  */
1438 define('TS_DB', 2);
1439
1440 /**
1441  * RFC 2822 format, for E-mail and HTTP headers
1442  */
1443 define('TS_RFC2822', 3);
1444
1445 /**
1446  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1447  *
1448  * This is used by Special:Export
1449  */
1450 define('TS_ISO_8601', 4);
1451
1452 /**
1453  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1454  *
1455  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1456  *       DateTime tag and page 36 for the DateTimeOriginal and
1457  *       DateTimeDigitized tags.
1458  */
1459 define('TS_EXIF', 5);
1460
1461 /**
1462  * Oracle format time.
1463  */
1464 define('TS_ORACLE', 6);
1465
1466 /**
1467  * Postgres format time.
1468  */
1469 define('TS_POSTGRES', 7);
1470
1471 /**
1472  * @param mixed $outputtype A timestamp in one of the supported formats, the
1473  *                          function will autodetect which format is supplied
1474  *                          and act accordingly.
1475  * @return string Time in the format specified in $outputtype
1476  */
1477 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1478         $uts = 0;
1479         $da = array();
1480         if ($ts==0) {
1481                 $uts=time();
1482         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1483                 # TS_DB
1484         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1485                 # TS_EXIF
1486         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1487                 # TS_MW
1488         } elseif (preg_match('/^\d{1,13}$/D',$ts)) {
1489                 # TS_UNIX
1490                 $uts = $ts;
1491         } elseif (preg_match('/^\d{1,2}-...-\d\d(?:\d\d)? \d\d\.\d\d\.\d\d/', $ts)) {
1492                 # TS_ORACLE
1493                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1494                                 str_replace("+00:00", "UTC", $ts)));
1495         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1496                 # TS_ISO_8601
1497         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1498                 # TS_POSTGRES
1499         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1500                 # TS_POSTGRES
1501         } else {
1502                 # Bogus value; fall back to the epoch...
1503                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1504                 $uts = 0;
1505         }
1506
1507         if (count( $da ) ) {
1508                 // Warning! gmmktime() acts oddly if the month or day is set to 0
1509                 // We may want to handle that explicitly at some point
1510                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1511                         (int)$da[2],(int)$da[3],(int)$da[1]);
1512         }
1513
1514         switch($outputtype) {
1515                 case TS_UNIX:
1516                         return $uts;
1517                 case TS_MW:
1518                         return gmdate( 'YmdHis', $uts );
1519                 case TS_DB:
1520                         return gmdate( 'Y-m-d H:i:s', $uts );
1521                 case TS_ISO_8601:
1522                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1523                 // This shouldn't ever be used, but is included for completeness
1524                 case TS_EXIF:
1525                         return gmdate(  'Y:m:d H:i:s', $uts );
1526                 case TS_RFC2822:
1527                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1528                 case TS_ORACLE:
1529                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1530                 case TS_POSTGRES:
1531                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1532                 default:
1533                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1534         }
1535 }
1536
1537 /**
1538  * Return a formatted timestamp, or null if input is null.
1539  * For dealing with nullable timestamp columns in the database.
1540  * @param int $outputtype
1541  * @param string $ts
1542  * @return string
1543  */
1544 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1545         if( is_null( $ts ) ) {
1546                 return null;
1547         } else {
1548                 return wfTimestamp( $outputtype, $ts );
1549         }
1550 }
1551
1552 /**
1553  * Check if the operating system is Windows
1554  *
1555  * @return bool True if it's Windows, False otherwise.
1556  */
1557 function wfIsWindows() {
1558         if (substr(php_uname(), 0, 7) == 'Windows') {
1559                 return true;
1560         } else {
1561                 return false;
1562         }
1563 }
1564
1565 /**
1566  * Swap two variables
1567  */
1568 function swap( &$x, &$y ) {
1569         $z = $x;
1570         $x = $y;
1571         $y = $z;
1572 }
1573
1574 function wfGetCachedNotice( $name ) {
1575         global $wgOut, $parserMemc;
1576         $fname = 'wfGetCachedNotice';
1577         wfProfileIn( $fname );
1578
1579         $needParse = false;
1580
1581         if( $name === 'default' ) {
1582                 // special case
1583                 global $wgSiteNotice;
1584                 $notice = $wgSiteNotice;
1585                 if( empty( $notice ) ) {
1586                         wfProfileOut( $fname );
1587                         return false;
1588                 }
1589         } else {
1590                 $notice = wfMsgForContentNoTrans( $name );
1591                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1592                         wfProfileOut( $fname );
1593                         return( false );
1594                 }
1595         }
1596
1597         $cachedNotice = $parserMemc->get( wfMemcKey( $name ) );
1598         if( is_array( $cachedNotice ) ) {
1599                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1600                         $notice = $cachedNotice['html'];
1601                 } else {
1602                         $needParse = true;
1603                 }
1604         } else {
1605                 $needParse = true;
1606         }
1607
1608         if( $needParse ) {
1609                 if( is_object( $wgOut ) ) {
1610                         $parsed = $wgOut->parse( $notice );
1611                         $parserMemc->set( wfMemcKey( $name ), array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1612                         $notice = $parsed;
1613                 } else {
1614                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1615                         $notice = '';
1616                 }
1617         }
1618
1619         wfProfileOut( $fname );
1620         return $notice;
1621 }
1622
1623 function wfGetNamespaceNotice() {
1624         global $wgTitle;
1625
1626         # Paranoia
1627         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1628                 return "";
1629
1630         $fname = 'wfGetNamespaceNotice';
1631         wfProfileIn( $fname );
1632
1633         $key = "namespacenotice-" . $wgTitle->getNsText();
1634         $namespaceNotice = wfGetCachedNotice( $key );
1635         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1636                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1637         } else {
1638                 $namespaceNotice = "";
1639         }
1640
1641         wfProfileOut( $fname );
1642         return $namespaceNotice;
1643 }
1644
1645 function wfGetSiteNotice() {
1646         global $wgUser, $wgSiteNotice;
1647         $fname = 'wfGetSiteNotice';
1648         wfProfileIn( $fname );
1649         $siteNotice = '';
1650
1651         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1652                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1653                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1654                 } else {
1655                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1656                         if( !$anonNotice ) {
1657                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1658                         } else {
1659                                 $siteNotice = $anonNotice;
1660                         }
1661                 }
1662                 if( !$siteNotice ) {
1663                         $siteNotice = wfGetCachedNotice( 'default' );
1664                 }
1665         }
1666
1667         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1668         wfProfileOut( $fname );
1669         return $siteNotice;
1670 }
1671
1672 /**
1673  * BC wrapper for MimeMagic::singleton()
1674  * @deprecated
1675  */
1676 function &wfGetMimeMagic() {
1677         return MimeMagic::singleton();
1678 }
1679
1680 /**
1681  * Tries to get the system directory for temporary files.
1682  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1683  * and if none are set /tmp is returned as the generic Unix default.
1684  *
1685  * NOTE: When possible, use the tempfile() function to create temporary
1686  * files to avoid race conditions on file creation, etc.
1687  *
1688  * @return string
1689  */
1690 function wfTempDir() {
1691         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1692                 $tmp = getenv( $var );
1693                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1694                         return $tmp;
1695                 }
1696         }
1697         # Hope this is Unix of some kind!
1698         return '/tmp';
1699 }
1700
1701 /**
1702  * Make directory, and make all parent directories if they don't exist
1703  */
1704 function wfMkdirParents( $fullDir, $mode = 0777 ) {
1705         if( strval( $fullDir ) === '' )
1706                 return true;
1707         if( file_exists( $fullDir ) )
1708                 return true;
1709
1710         # Go back through the paths to find the first directory that exists
1711         $currentDir = $fullDir;
1712         $createList = array();
1713         while ( strval( $currentDir ) !== '' && !file_exists( $currentDir ) ) {
1714                 # Strip trailing slashes
1715                 $currentDir = rtrim( $currentDir, '/\\' );
1716
1717                 # Add to create list
1718                 $createList[] = $currentDir;
1719
1720                 # Find next delimiter searching from the end
1721                 $p = max( strrpos( $currentDir, '/' ), strrpos( $currentDir, '\\' ) );
1722                 if ( $p === false ) {
1723                         $currentDir = false;
1724                 } else {
1725                         $currentDir = substr( $currentDir, 0, $p );
1726                 }
1727         }
1728
1729         if ( count( $createList ) == 0 ) {
1730                 # Directory specified already exists
1731                 return true;
1732         } elseif ( $currentDir === false ) {
1733                 # Went all the way back to root and it apparently doesn't exist
1734                 wfDebugLog( 'mkdir', "Root doesn't exist?\n" );
1735                 return false;
1736         }
1737         # Now go forward creating directories
1738         $createList = array_reverse( $createList );
1739
1740         # Is the parent directory writable?
1741         if ( $currentDir === '' ) {
1742                 $currentDir = '/';
1743         }
1744         if ( !is_writable( $currentDir ) ) {
1745                 wfDebugLog( 'mkdir', "Not writable: $currentDir\n" );
1746                 return false;
1747         }
1748
1749         foreach ( $createList as $dir ) {
1750                 # use chmod to override the umask, as suggested by the PHP manual
1751                 if ( !mkdir( $dir, $mode ) || !chmod( $dir, $mode ) ) {
1752                         wfDebugLog( 'mkdir', "Unable to create directory $dir\n" );
1753                         return false;
1754                 }
1755         }
1756         return true;
1757 }
1758
1759 /**
1760  * Increment a statistics counter
1761  */
1762 function wfIncrStats( $key ) {
1763         global $wgStatsMethod;
1764
1765         if( $wgStatsMethod == 'udp' ) {
1766                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
1767                 static $socket;
1768                 if (!$socket) {
1769                         $socket=socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
1770                         $statline="stats/{$wgDBname} - 1 1 1 1 1 -total\n";
1771                         socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1772                 }
1773                 $statline="stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
1774                 @socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1775         } elseif( $wgStatsMethod == 'cache' ) {
1776                 global $wgMemc;
1777                 $key = wfMemcKey( 'stats', $key );
1778                 if ( is_null( $wgMemc->incr( $key ) ) ) {
1779                         $wgMemc->add( $key, 1 );
1780                 }
1781         } else {
1782                 // Disabled
1783         }
1784 }
1785
1786 /**
1787  * @param mixed $nr The number to format
1788  * @param int $acc The number of digits after the decimal point, default 2
1789  * @param bool $round Whether or not to round the value, default true
1790  * @return float
1791  */
1792 function wfPercent( $nr, $acc = 2, $round = true ) {
1793         $ret = sprintf( "%.${acc}f", $nr );
1794         return $round ? round( $ret, $acc ) . '%' : "$ret%";
1795 }
1796
1797 /**
1798  * Appends to second array if $value differs from that in $default
1799  */
1800 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
1801         if ( is_null( $changed ) ) {
1802                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
1803         }
1804         if ( $default[$key] !== $value ) {
1805                 $changed[$key] = $value;
1806         }
1807 }
1808
1809 /**
1810  * Since wfMsg() and co suck, they don't return false if the message key they
1811  * looked up didn't exist but a XHTML string, this function checks for the
1812  * nonexistance of messages by looking at wfMsg() output
1813  *
1814  * @param $msg      The message key looked up
1815  * @param $wfMsgOut The output of wfMsg*()
1816  * @return bool
1817  */
1818 function wfEmptyMsg( $msg, $wfMsgOut ) {
1819         return $wfMsgOut === htmlspecialchars( "<$msg>" );
1820 }
1821
1822 /**
1823  * Find out whether or not a mixed variable exists in a string
1824  *
1825  * @param mixed  needle
1826  * @param string haystack
1827  * @return bool
1828  */
1829 function in_string( $needle, $str ) {
1830         return strpos( $str, $needle ) !== false;
1831 }
1832
1833 function wfSpecialList( $page, $details ) {
1834         global $wgContLang;
1835         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
1836         return $page . $details;
1837 }
1838
1839 /**
1840  * Returns a regular expression of url protocols
1841  *
1842  * @return string
1843  */
1844 function wfUrlProtocols() {
1845         global $wgUrlProtocols;
1846
1847         // Support old-style $wgUrlProtocols strings, for backwards compatibility
1848         // with LocalSettings files from 1.5
1849         if ( is_array( $wgUrlProtocols ) ) {
1850                 $protocols = array();
1851                 foreach ($wgUrlProtocols as $protocol)
1852                         $protocols[] = preg_quote( $protocol, '/' );
1853
1854                 return implode( '|', $protocols );
1855         } else {
1856                 return $wgUrlProtocols;
1857         }
1858 }
1859
1860 /**
1861  * Safety wrapper around ini_get() for boolean settings.
1862  * The values returned from ini_get() are pre-normalized for settings
1863  * set via php.ini or php_flag/php_admin_flag... but *not*
1864  * for those set via php_value/php_admin_value.
1865  *
1866  * It's fairly common for people to use php_value instead of php_flag,
1867  * which can leave you with an 'off' setting giving a false positive
1868  * for code that just takes the ini_get() return value as a boolean.
1869  *
1870  * To make things extra interesting, setting via php_value accepts
1871  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
1872  * Unrecognized values go false... again opposite PHP's own coercion
1873  * from string to bool.
1874  *
1875  * Luckily, 'properly' set settings will always come back as '0' or '1',
1876  * so we only have to worry about them and the 'improper' settings.
1877  *
1878  * I frickin' hate PHP... :P
1879  *
1880  * @param string $setting
1881  * @return bool
1882  */
1883 function wfIniGetBool( $setting ) {
1884         $val = ini_get( $setting );
1885         // 'on' and 'true' can't have whitespace around them, but '1' can.
1886         return strtolower( $val ) == 'on'
1887                 || strtolower( $val ) == 'true'
1888                 || strtolower( $val ) == 'yes'
1889                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
1890 }
1891
1892 /**
1893  * Execute a shell command, with time and memory limits mirrored from the PHP
1894  * configuration if supported.
1895  * @param $cmd Command line, properly escaped for shell.
1896  * @param &$retval optional, will receive the program's exit code.
1897  *                 (non-zero is usually failure)
1898  * @return collected stdout as a string (trailing newlines stripped)
1899  */
1900 function wfShellExec( $cmd, &$retval=null ) {
1901         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
1902
1903         if( wfIniGetBool( 'safe_mode' ) ) {
1904                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
1905                 $retval = 1;
1906                 return "Unable to run external programs in safe mode.";
1907         }
1908
1909         if ( php_uname( 's' ) == 'Linux' ) {
1910                 $time = intval( ini_get( 'max_execution_time' ) );
1911                 $mem = intval( $wgMaxShellMemory );
1912                 $filesize = intval( $wgMaxShellFileSize );
1913
1914                 if ( $time > 0 && $mem > 0 ) {
1915                         $script = "$IP/bin/ulimit4.sh";
1916                         if ( is_executable( $script ) ) {
1917                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
1918                         }
1919                 }
1920         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
1921                 # This is a hack to work around PHP's flawed invocation of cmd.exe
1922                 # http://news.php.net/php.internals/21796
1923                 $cmd = '"' . $cmd . '"';
1924         }
1925         wfDebug( "wfShellExec: $cmd\n" );
1926
1927         $retval = 1; // error by default?
1928         ob_start();
1929         passthru( $cmd, $retval );
1930         $output = ob_get_contents();
1931         ob_end_clean();
1932         return $output;
1933
1934 }
1935
1936 /**
1937  * This function works like "use VERSION" in Perl, the program will die with a
1938  * backtrace if the current version of PHP is less than the version provided
1939  *
1940  * This is useful for extensions which due to their nature are not kept in sync
1941  * with releases, and might depend on other versions of PHP than the main code
1942  *
1943  * Note: PHP might die due to parsing errors in some cases before it ever
1944  *       manages to call this function, such is life
1945  *
1946  * @see perldoc -f use
1947  *
1948  * @param mixed $version The version to check, can be a string, an integer, or
1949  *                       a float
1950  */
1951 function wfUsePHP( $req_ver ) {
1952         $php_ver = PHP_VERSION;
1953
1954         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
1955                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
1956 }
1957
1958 /**
1959  * This function works like "use VERSION" in Perl except it checks the version
1960  * of MediaWiki, the program will die with a backtrace if the current version
1961  * of MediaWiki is less than the version provided.
1962  *
1963  * This is useful for extensions which due to their nature are not kept in sync
1964  * with releases
1965  *
1966  * @see perldoc -f use
1967  *
1968  * @param mixed $version The version to check, can be a string, an integer, or
1969  *                       a float
1970  */
1971 function wfUseMW( $req_ver ) {
1972         global $wgVersion;
1973
1974         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
1975                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
1976 }
1977
1978 /**
1979  * @deprecated use StringUtils::escapeRegexReplacement
1980  */
1981 function wfRegexReplacement( $string ) {
1982         return StringUtils::escapeRegexReplacement( $string );
1983 }
1984
1985 /**
1986  * Return the final portion of a pathname.
1987  * Reimplemented because PHP5's basename() is buggy with multibyte text.
1988  * http://bugs.php.net/bug.php?id=33898
1989  *
1990  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
1991  * We'll consider it so always, as we don't want \s in our Unix paths either.
1992  *
1993  * @param string $path
1994  * @param string $suffix to remove if present
1995  * @return string
1996  */
1997 function wfBaseName( $path, $suffix='' ) {
1998         $encSuffix = ($suffix == '')
1999                 ? ''
2000                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2001         $matches = array();
2002         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2003                 return $matches[1];
2004         } else {
2005                 return '';
2006         }
2007 }
2008
2009 /**
2010  * Generate a relative path name to the given file.
2011  * May explode on non-matching case-insensitive paths,
2012  * funky symlinks, etc.
2013  *
2014  * @param string $path Absolute destination path including target filename
2015  * @param string $from Absolute source path, directory only
2016  * @return string
2017  */
2018 function wfRelativePath( $path, $from ) {
2019         // Normalize mixed input on Windows...
2020         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2021         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2022
2023         // Trim trailing slashes -- fix for drive root
2024         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2025         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2026
2027         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2028         $against = explode( DIRECTORY_SEPARATOR, $from );
2029
2030         if( $pieces[0] !== $against[0] ) {
2031                 // Non-matching Windows drive letters?
2032                 // Return a full path.
2033                 return $path;
2034         }
2035
2036         // Trim off common prefix
2037         while( count( $pieces ) && count( $against )
2038                 && $pieces[0] == $against[0] ) {
2039                 array_shift( $pieces );
2040                 array_shift( $against );
2041         }
2042
2043         // relative dots to bump us to the parent
2044         while( count( $against ) ) {
2045                 array_unshift( $pieces, '..' );
2046                 array_shift( $against );
2047         }
2048
2049         array_push( $pieces, wfBaseName( $path ) );
2050
2051         return implode( DIRECTORY_SEPARATOR, $pieces );
2052 }
2053
2054 /**
2055  * array_merge() does awful things with "numeric" indexes, including
2056  * string indexes when happen to look like integers. When we want
2057  * to merge arrays with arbitrary string indexes, we don't want our
2058  * arrays to be randomly corrupted just because some of them consist
2059  * of numbers.
2060  *
2061  * Fuck you, PHP. Fuck you in the ear!
2062  *
2063  * @param array $array1, [$array2, [...]]
2064  * @return array
2065  */
2066 function wfArrayMerge( $array1/* ... */ ) {
2067         $out = $array1;
2068         for( $i = 1; $i < func_num_args(); $i++ ) {
2069                 foreach( func_get_arg( $i ) as $key => $value ) {
2070                         $out[$key] = $value;
2071                 }
2072         }
2073         return $out;
2074 }
2075
2076 /**
2077  * Make a URL index, appropriate for the el_index field of externallinks.
2078  */
2079 function wfMakeUrlIndex( $url ) {
2080         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2081         wfSuppressWarnings();
2082         $bits = parse_url( $url );
2083         wfRestoreWarnings();
2084         if ( !$bits ) {
2085                 return false;
2086         }
2087         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2088         $delimiter = '';
2089         if ( in_array( $bits['scheme'] . '://' , $wgUrlProtocols ) ) {
2090                 $delimiter = '://';
2091         } elseif ( in_array( $bits['scheme'] .':' , $wgUrlProtocols ) ) {
2092                 $delimiter = ':';
2093                 // parse_url detects for news: and mailto: the host part of an url as path
2094                 // We have to correct this wrong detection
2095                 if ( isset ( $bits['path'] ) ) {
2096                         $bits['host'] = $bits['path'];
2097                         $bits['path'] = '';
2098                 }
2099         } else {
2100                 return false;
2101         }
2102
2103         // Reverse the labels in the hostname, convert to lower case
2104         // For emails reverse domainpart only
2105         if ( $bits['scheme'] == 'mailto' ) {
2106                 $mailparts = explode( '@', $bits['host'], 2 );
2107                 if ( count($mailparts) === 2 ) {
2108                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2109                 } else {
2110                         // No domain specified, don't mangle it
2111                         $domainpart = '';
2112                 }
2113                 $reversedHost = $domainpart . '@' . $mailparts[0];
2114         } else {
2115                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2116         }
2117         // Add an extra dot to the end
2118         // Why? Is it in wrong place in mailto links?
2119         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2120                 $reversedHost .= '.';
2121         }
2122         // Reconstruct the pseudo-URL
2123         $prot = $bits['scheme'];
2124         $index = "$prot$delimiter$reversedHost";
2125         // Leave out user and password. Add the port, path, query and fragment
2126         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
2127         if ( isset( $bits['path'] ) ) {
2128                 $index .= $bits['path'];
2129         } else {
2130                 $index .= '/';
2131         }
2132         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
2133         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
2134         return $index;
2135 }
2136
2137 /**
2138  * Do any deferred updates and clear the list
2139  * TODO: This could be in Wiki.php if that class made any sense at all
2140  */
2141 function wfDoUpdates()
2142 {
2143         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2144         foreach ( $wgDeferredUpdateList as $update ) {
2145                 $update->doUpdate();
2146         }
2147         foreach ( $wgPostCommitUpdateList as $update ) {
2148                 $update->doUpdate();
2149         }
2150         $wgDeferredUpdateList = array();
2151         $wgPostCommitUpdateList = array();
2152 }
2153
2154 /**
2155  * @deprecated use StringUtils::explodeMarkup
2156  */
2157 function wfExplodeMarkup( $separator, $text ) {
2158         return StringUtils::explodeMarkup( $separator, $text );
2159 }
2160
2161 /**
2162  * Convert an arbitrarily-long digit string from one numeric base
2163  * to another, optionally zero-padding to a minimum column width.
2164  *
2165  * Supports base 2 through 36; digit values 10-36 are represented
2166  * as lowercase letters a-z. Input is case-insensitive.
2167  *
2168  * @param $input string of digits
2169  * @param $sourceBase int 2-36
2170  * @param $destBase int 2-36
2171  * @param $pad int 1 or greater
2172  * @param $lowercase bool
2173  * @return string or false on invalid input
2174  */
2175 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2176         $input = strval( $input );
2177         if( $sourceBase < 2 ||
2178                 $sourceBase > 36 ||
2179                 $destBase < 2 ||
2180                 $destBase > 36 ||
2181                 $pad < 1 ||
2182                 $sourceBase != intval( $sourceBase ) ||
2183                 $destBase != intval( $destBase ) ||
2184                 $pad != intval( $pad ) ||
2185                 !is_string( $input ) ||
2186                 $input == '' ) {
2187                 return false;
2188         }
2189         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2190         $inDigits = array();
2191         $outChars = '';
2192
2193         // Decode and validate input string
2194         $input = strtolower( $input );
2195         for( $i = 0; $i < strlen( $input ); $i++ ) {
2196                 $n = strpos( $digitChars, $input{$i} );
2197                 if( $n === false || $n > $sourceBase ) {
2198                         return false;
2199                 }
2200                 $inDigits[] = $n;
2201         }
2202
2203         // Iterate over the input, modulo-ing out an output digit
2204         // at a time until input is gone.
2205         while( count( $inDigits ) ) {
2206                 $work = 0;
2207                 $workDigits = array();
2208
2209                 // Long division...
2210                 foreach( $inDigits as $digit ) {
2211                         $work *= $sourceBase;
2212                         $work += $digit;
2213
2214                         if( $work < $destBase ) {
2215                                 // Gonna need to pull another digit.
2216                                 if( count( $workDigits ) ) {
2217                                         // Avoid zero-padding; this lets us find
2218                                         // the end of the input very easily when
2219                                         // length drops to zero.
2220                                         $workDigits[] = 0;
2221                                 }
2222                         } else {
2223                                 // Finally! Actual division!
2224                                 $workDigits[] = intval( $work / $destBase );
2225
2226                                 // Isn't it annoying that most programming languages
2227                                 // don't have a single divide-and-remainder operator,
2228                                 // even though the CPU implements it that way?
2229                                 $work = $work % $destBase;
2230                         }
2231                 }
2232
2233                 // All that division leaves us with a remainder,
2234                 // which is conveniently our next output digit.
2235                 $outChars .= $digitChars[$work];
2236
2237                 // And we continue!
2238                 $inDigits = $workDigits;
2239         }
2240
2241         while( strlen( $outChars ) < $pad ) {
2242                 $outChars .= '0';
2243         }
2244
2245         return strrev( $outChars );
2246 }
2247
2248 /**
2249  * Create an object with a given name and an array of construct parameters
2250  * @param string $name
2251  * @param array $p parameters
2252  */
2253 function wfCreateObject( $name, $p ){
2254         $p = array_values( $p );
2255         switch ( count( $p ) ) {
2256                 case 0:
2257                         return new $name;
2258                 case 1:
2259                         return new $name( $p[0] );
2260                 case 2:
2261                         return new $name( $p[0], $p[1] );
2262                 case 3:
2263                         return new $name( $p[0], $p[1], $p[2] );
2264                 case 4:
2265                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2266                 case 5:
2267                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2268                 case 6:
2269                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2270                 default:
2271                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2272         }
2273 }
2274
2275 /**
2276  * Aliases for modularized functions
2277  */
2278 function wfGetHTTP( $url, $timeout = 'default' ) {
2279         return Http::get( $url, $timeout );
2280 }
2281 function wfIsLocalURL( $url ) {
2282         return Http::isLocalURL( $url );
2283 }
2284
2285 function wfHttpOnlySafe() {
2286         global $wgHttpOnlyBlacklist;
2287         if( !version_compare("5.2", PHP_VERSION, "<") )
2288                 return false;
2289
2290         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2291                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2292                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2293                                 return false;
2294                         }
2295                 }
2296         }
2297
2298         return true;
2299 }
2300
2301 /**
2302  * Initialise php session
2303  */
2304 function wfSetupSession() {
2305         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
2306         if( $wgSessionsInMemcached ) {
2307                 require_once( 'MemcachedSessions.php' );
2308         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2309                 # If it's left on 'user' or another setting from another
2310                 # application, it will end up failing. Try to recover.
2311                 ini_set ( 'session.save_handler', 'files' );
2312         }
2313         $httpOnlySafe = wfHttpOnlySafe();
2314         wfDebugLog( 'cookie',
2315                 'session_set_cookie_params: "' . implode( '", "',
2316                         array(
2317                                 0,
2318                                 $wgCookiePath,
2319                                 $wgCookieDomain,
2320                                 $wgCookieSecure,
2321                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2322         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2323                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2324         } else {
2325                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2326                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2327         }
2328         session_cache_limiter( 'private, must-revalidate' );
2329         wfSuppressWarnings();
2330         session_start();
2331         wfRestoreWarnings();
2332 }
2333
2334 /**
2335  * Get an object from the precompiled serialized directory
2336  *
2337  * @return mixed The variable on success, false on failure
2338  */
2339 function wfGetPrecompiledData( $name ) {
2340         global $IP;
2341
2342         $file = "$IP/serialized/$name";
2343         if ( file_exists( $file ) ) {
2344                 $blob = file_get_contents( $file );
2345                 if ( $blob ) {
2346                         return unserialize( $blob );
2347                 }
2348         }
2349         return false;
2350 }
2351
2352 function wfGetCaller( $level = 2 ) {
2353         $backtrace = wfDebugBacktrace();
2354         if ( isset( $backtrace[$level] ) ) {
2355                 return wfFormatStackFrame($backtrace[$level]);
2356         } else {
2357                 $caller = 'unknown';
2358         }
2359         return $caller;
2360 }
2361
2362 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2363 function wfGetAllCallers() {
2364         return implode('/', array_map('wfFormatStackFrame',array_reverse(wfDebugBacktrace())));
2365 }
2366
2367 /** Return a string representation of frame */
2368 function wfFormatStackFrame($frame) {
2369         return isset( $frame["class"] )?
2370                 $frame["class"]."::".$frame["function"]:
2371                 $frame["function"];
2372 }
2373
2374 /**
2375  * Get a cache key
2376  */
2377 function wfMemcKey( /*... */ ) {
2378         $args = func_get_args();
2379         $key = wfWikiID() . ':' . implode( ':', $args );
2380         return $key;
2381 }
2382
2383 /**
2384  * Get a cache key for a foreign DB
2385  */
2386 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2387         $args = array_slice( func_get_args(), 2 );
2388         if ( $prefix ) {
2389                 $key = "$db-$prefix:" . implode( ':', $args );
2390         } else {
2391                 $key = $db . ':' . implode( ':', $args );
2392         }
2393         return $key;
2394 }
2395
2396 /**
2397  * Get an ASCII string identifying this wiki
2398  * This is used as a prefix in memcached keys
2399  */
2400 function wfWikiID( $db = null ) {
2401         if( $db instanceof Database ) {
2402                 return $db->getWikiID();
2403         } else {
2404         global $wgDBprefix, $wgDBname;
2405                 if ( $wgDBprefix ) {
2406                         return "$wgDBname-$wgDBprefix";
2407                 } else {
2408                         return $wgDBname;
2409                 }
2410         }
2411 }
2412
2413 /**
2414  * Split a wiki ID into DB name and table prefix
2415  */
2416 function wfSplitWikiID( $wiki ) {
2417         $bits = explode( '-', $wiki, 2 );
2418         if ( count( $bits ) < 2 ) {
2419                 $bits[] = '';
2420         }
2421         return $bits;
2422 }
2423
2424 /*
2425  * Get a Database object.
2426  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2427  *                master (for write queries), DB_SLAVE for potentially lagged
2428  *                read queries, or an integer >= 0 for a particular server.
2429  *
2430  * @param mixed $groups Query groups. An array of group names that this query
2431  *              belongs to. May contain a single string if the query is only
2432  *              in one group.
2433  *
2434  * @param string $wiki The wiki ID, or false for the current wiki
2435  *
2436  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
2437  * will always return the same object, unless the underlying connection or load
2438  * balancer is manually destroyed.
2439  */
2440 function &wfGetDB( $db = DB_LAST, $groups = array(), $wiki = false ) {
2441         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2442 }
2443
2444 /**
2445  * Get a load balancer object.
2446  *
2447  * @param array $groups List of query groups
2448  * @param string $wiki Wiki ID, or false for the current wiki
2449  * @return LoadBalancer
2450  */
2451 function wfGetLB( $wiki = false ) {
2452         return wfGetLBFactory()->getMainLB( $wiki );
2453 }
2454
2455 /**
2456  * Get the load balancer factory object
2457  */
2458 function &wfGetLBFactory() {
2459         return LBFactory::singleton();
2460 }
2461
2462 /**
2463  * Find a file.
2464  * Shortcut for RepoGroup::singleton()->findFile()
2465  * @param mixed $title Title object or string. May be interwiki.
2466  * @param mixed $time Requested time for an archived image, or false for the
2467  *                    current version. An image object will be returned which
2468  *                    was created at the specified time.
2469  * @param mixed $flags FileRepo::FIND_ flags
2470  * @return File, or false if the file does not exist
2471  */
2472 function wfFindFile( $title, $time = false, $flags = 0 ) {
2473         return RepoGroup::singleton()->findFile( $title, $time, $flags );
2474 }
2475
2476 /**
2477  * Get an object referring to a locally registered file.
2478  * Returns a valid placeholder object if the file does not exist.
2479  */
2480 function wfLocalFile( $title ) {
2481         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2482 }
2483
2484 /**
2485  * Should low-performance queries be disabled?
2486  *
2487  * @return bool
2488  */
2489 function wfQueriesMustScale() {
2490         global $wgMiserMode;
2491         return $wgMiserMode
2492                 || ( SiteStats::pages() > 100000
2493                 && SiteStats::edits() > 1000000
2494                 && SiteStats::users() > 10000 );
2495 }
2496
2497 /**
2498  * Get the path to a specified script file, respecting file
2499  * extensions; this is a wrapper around $wgScriptExtension etc.
2500  *
2501  * @param string $script Script filename, sans extension
2502  * @return string
2503  */
2504 function wfScript( $script = 'index' ) {
2505         global $wgScriptPath, $wgScriptExtension;
2506         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
2507 }
2508
2509 /**
2510  * Convenience function converts boolean values into "true"
2511  * or "false" (string) values
2512  *
2513  * @param bool $value
2514  * @return string
2515  */
2516 function wfBoolToStr( $value ) {
2517         return $value ? 'true' : 'false';
2518 }
2519
2520 /**
2521  * Load an extension messages file
2522  *
2523  * @param string $extensionName Name of extension to load messages from\for.
2524  * @param string $langcode Language to load messages for, or false for default
2525  *                         behvaiour (en, content language and user language).
2526  */
2527 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
2528         global $wgExtensionMessagesFiles, $wgMessageCache, $wgLang, $wgContLang;
2529
2530         #For recording whether extension message files have been loaded in a given language.
2531         static $loaded = array();
2532
2533         if( !array_key_exists( $extensionName, $loaded ) ) {
2534                 $loaded[$extensionName] = array();
2535         }
2536
2537         if( !$langcode && !array_key_exists( '*', $loaded[$extensionName] ) ) {
2538                 # Just do en, content language and user language.
2539                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], false );
2540                 # Mark that they have been loaded.
2541                 $loaded[$extensionName]['en'] = true;
2542                 $loaded[$extensionName][$wgLang->getCode()] = true;
2543                 $loaded[$extensionName][$wgContLang->getCode()] = true;
2544                 # Mark that this part has been done to avoid weird if statements.
2545                 $loaded[$extensionName]['*'] = true;
2546         } elseif( is_string( $langcode ) && !array_key_exists( $langcode, $loaded[$extensionName] ) ) {
2547                 # Load messages for specified language.
2548                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], $langcode );
2549                 # Mark that they have been loaded.
2550                 $loaded[$extensionName][$langcode] = true;
2551         }
2552 }
2553
2554 /**
2555  * Get a platform-independent path to the null file, e.g.
2556  * /dev/null
2557  *
2558  * @return string
2559  */
2560 function wfGetNull() {
2561         return wfIsWindows()
2562                 ? 'NUL'
2563                 : '/dev/null';
2564 }
2565
2566 /**
2567  * Displays a maxlag error
2568  *
2569  * @param string $host Server that lags the most
2570  * @param int $lag Maxlag (actual)
2571  * @param int $maxLag Maxlag (requested)
2572  */
2573 function wfMaxlagError( $host, $lag, $maxLag ) {
2574         global $wgShowHostnames;
2575         header( 'HTTP/1.1 503 Service Unavailable' );
2576         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
2577         header( 'X-Database-Lag: ' . intval( $lag ) );
2578         header( 'Content-Type: text/plain' );
2579         if( $wgShowHostnames ) {
2580                 echo "Waiting for $host: $lag seconds lagged\n";
2581         } else {
2582                 echo "Waiting for a database server: $lag seconds lagged\n";
2583         }
2584 }
2585
2586 /**
2587  * Throws an E_USER_NOTICE saying that $function is deprecated
2588  * @param string $function
2589  * @return null
2590  */
2591 function wfDeprecated( $function ) {
2592         global $wgDebugLogFile;
2593         if ( !$wgDebugLogFile ) {
2594                 return;
2595         }
2596         $callers = wfDebugBacktrace();
2597         if( isset( $callers[2] ) ){
2598                 $callerfunc = $callers[2];
2599                 $callerfile = $callers[1];
2600                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ){
2601                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
2602                 } else {
2603                         $file = '(internal function)';
2604                 }
2605                 $func = '';
2606                 if( isset( $callerfunc['class'] ) )
2607                         $func .= $callerfunc['class'] . '::';
2608                 $func .= @$callerfunc['function'];
2609                 $msg = "Use of $function is deprecated. Called from $func in $file";
2610         } else {
2611                 $msg = "Use of $function is deprecated.";
2612         }
2613         wfDebug( "$msg\n" );
2614 }
2615
2616 /**
2617  * Sleep until the worst slave's replication lag is less than or equal to
2618  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
2619  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
2620  * a no-op if there are no slaves.
2621  *
2622  * Every time the function has to wait for a slave, it will print a message to
2623  * that effect (and then sleep for a little while), so it's probably not best
2624  * to use this outside maintenance scripts in its present form.
2625  *
2626  * @param int $maxLag
2627  * @return null
2628  */
2629 function wfWaitForSlaves( $maxLag ) {
2630         if( $maxLag ) {
2631                 $lb = wfGetLB();
2632                 list( $host, $lag ) = $lb->getMaxLag();
2633                 while( $lag > $maxLag ) {
2634                         $name = @gethostbyaddr( $host );
2635                         if( $name !== false ) {
2636                                 $host = $name;
2637                         }
2638                         print "Waiting for $host (lagged $lag seconds)...\n";
2639                         sleep($maxLag);
2640                         list( $host, $lag ) = $lb->getMaxLag();
2641                 }
2642         }
2643 }
2644
2645 /** Generate a random 32-character hexadecimal token.
2646  * @param mixed $salt Some sort of salt, if necessary, to add to random characters before hashing.
2647  */
2648 function wfGenerateToken( $salt = '' ) {
2649         $salt = serialize($salt);
2650
2651         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
2652 }