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         static $cache = array(); // Cache of unoutputted messages
 180
 181         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 182         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 183                 return;
 184         }
 185
 186         if ( $wgDebugComments && !$logonly ) {
 187                 $cache[] = $text;
 188
 189                 if ( !isset( $wgOut ) ) {
 190                         return;
 191                 }
 192                 if ( !StubObject::isRealObject( $wgOut ) ) {
 193                         if ( $recursion ) {
 194                                 return;
 195                         }
 196                         $recursion++;
 197                         $wgOut->_unstub();
 198                         $recursion--;
 199                 }
 200
 201                 // add the message and possible cached ones to the output
 202                 array_map( array( $wgOut, 'debug' ), $cache );
 203                 $cache = array();
 204         }
 205         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 206                 # Strip unprintables; they can switch terminal modes when binary data
 207                 # gets dumped, which is pretty annoying.
 208                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 209                 wfErrorLog( $text, $wgDebugLogFile );
 210         }
 211 }
 212
 213 /**
 214  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 215  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 216  *
 217  * @param $logGroup String
 218  * @param $text String
 219  * @param $public Bool: whether to log the event in the public log if no private
 220  *                     log file is specified, (default true)
 221  */
 222 function wfDebugLog( $logGroup, $text, $public = true ) {
 223         global $wgDebugLogGroups;
 224         if( $text{strlen( $text ) - 1} != "\n" ) $text .= "\n";
 225         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 226                 $time = wfTimestamp( TS_DB );
 227                 $wiki = wfWikiID();
 228                 wfErrorLog( "$time $wiki: $text", $wgDebugLogGroups[$logGroup] );
 229         } else if ( $public === true ) {
 230                 wfDebug( $text, true );
 231         }
 232 }
 233
 234 /**
 235  * Log for database errors
 236  * @param $text String: database error message.
 237  */
 238 function wfLogDBError( $text ) {
 239         global $wgDBerrorLog, $wgDBname;
 240         if ( $wgDBerrorLog ) {
 241                 $host = trim(`hostname`);
 242                 $text = date('D M j G:i:s T Y') . "\t$host\t$wgDBname\t$text";
 243                 wfErrorLog( $text, $wgDBerrorLog );
 244         }
 245 }
 246
 247 /**
 248  * Log to a file without getting "file size exceeded" signals
 249  */
 250 function wfErrorLog( $text, $file ) {
 251         wfSuppressWarnings();
 252         $exists = file_exists( $file );
 253         $size = $exists ? filesize( $file ) : false;
 254         if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 255                 error_log( $text, 3, $file );
 256         }
 257         wfRestoreWarnings();
 258 }
 259
 260 /**
 261  * @todo document
 262  */
 263 function wfLogProfilingData() {
 264         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 265         global $wgProfiler, $wgUser;
 266         if ( !isset( $wgProfiler ) )
 267                 return;
 268
 269         $now = wfTime();
 270         $elapsed = $now - $wgRequestTime;
 271         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 272         $forward = '';
 273         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 274                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 275         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 276                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 277         if( !empty( $_SERVER['HTTP_FROM'] ) )
 278                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 279         if( $forward )
 280                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 281         // Don't unstub $wgUser at this late stage just for statistics purposes
 282         if( StubObject::isRealObject($wgUser) && $wgUser->isAnon() )
 283                 $forward .= ' anon';
 284         $log = sprintf( "%s\t%04.3f\t%s\n",
 285           gmdate( 'YmdHis' ), $elapsed,
 286           urldecode( $wgRequest->getRequestURL() . $forward ) );
 287         if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 288                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 289         }
 290 }
 291
 292 /**
 293  * Check if the wiki read-only lock file is present. This can be used to lock
 294  * off editing functions, but doesn't guarantee that the database will not be
 295  * modified.
 296  * @return bool
 297  */
 298 function wfReadOnly() {
 299         global $wgReadOnlyFile, $wgReadOnly;
 300
 301         if ( !is_null( $wgReadOnly ) ) {
 302                 return (bool)$wgReadOnly;
 303         }
 304         if ( '' == $wgReadOnlyFile ) {
 305                 return false;
 306         }
 307         // Set $wgReadOnly for faster access next time
 308         if ( is_file( $wgReadOnlyFile ) ) {
 309                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 310         } else {
 311                 $wgReadOnly = false;
 312         }
 313         return (bool)$wgReadOnly;
 314 }
 315
 316 function wfReadOnlyReason() {
 317         global $wgReadOnly;
 318         wfReadOnly();
 319         return $wgReadOnly;
 320 }
 321
 322 /**
 323  * Get a message from anywhere, for the current user language.
 324  *
 325  * Use wfMsgForContent() instead if the message should NOT
 326  * change depending on the user preferences.
 327  *
 328  * @param $key String: lookup key for the message, usually
 329  *    defined in languages/Language.php
 330  *
 331  * This function also takes extra optional parameters (not
 332  * shown in the function definition), which can by used to
 333  * insert variable text into the predefined message.
 334  */
 335 function wfMsg( $key ) {
 336         $args = func_get_args();
 337         array_shift( $args );
 338         return wfMsgReal( $key, $args, true );
 339 }
 340
 341 /**
 342  * Same as above except doesn't transform the message
 343  */
 344 function wfMsgNoTrans( $key ) {
 345         $args = func_get_args();
 346         array_shift( $args );
 347         return wfMsgReal( $key, $args, true, false, false );
 348 }
 349
 350 /**
 351  * Get a message from anywhere, for the current global language
 352  * set with $wgLanguageCode.
 353  *
 354  * Use this if the message should NOT change  dependent on the
 355  * language set in the user's preferences. This is the case for
 356  * most text written into logs, as well as link targets (such as
 357  * the name of the copyright policy page). Link titles, on the
 358  * other hand, should be shown in the UI language.
 359  *
 360  * Note that MediaWiki allows users to change the user interface
 361  * language in their preferences, but a single installation
 362  * typically only contains content in one language.
 363  *
 364  * Be wary of this distinction: If you use wfMsg() where you should
 365  * use wfMsgForContent(), a user of the software may have to
 366  * customize over 70 messages in order to, e.g., fix a link in every
 367  * possible language.
 368  *
 369  * @param $key String: lookup key for the message, usually
 370  *    defined in languages/Language.php
 371  */
 372 function wfMsgForContent( $key ) {
 373         global $wgForceUIMsgAsContentMsg;
 374         $args = func_get_args();
 375         array_shift( $args );
 376         $forcontent = true;
 377         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 378                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 379                 $forcontent = false;
 380         return wfMsgReal( $key, $args, true, $forcontent );
 381 }
 382
 383 /**
 384  * Same as above except doesn't transform the message
 385  */
 386 function wfMsgForContentNoTrans( $key ) {
 387         global $wgForceUIMsgAsContentMsg;
 388         $args = func_get_args();
 389         array_shift( $args );
 390         $forcontent = true;
 391         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 392                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 393                 $forcontent = false;
 394         return wfMsgReal( $key, $args, true, $forcontent, false );
 395 }
 396
 397 /**
 398  * Get a message from the language file, for the UI elements
 399  */
 400 function wfMsgNoDB( $key ) {
 401         $args = func_get_args();
 402         array_shift( $args );
 403         return wfMsgReal( $key, $args, false );
 404 }
 405
 406 /**
 407  * Get a message from the language file, for the content
 408  */
 409 function wfMsgNoDBForContent( $key ) {
 410         global $wgForceUIMsgAsContentMsg;
 411         $args = func_get_args();
 412         array_shift( $args );
 413         $forcontent = true;
 414         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 415                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 416                 $forcontent = false;
 417         return wfMsgReal( $key, $args, false, $forcontent );
 418 }
 419
 420
 421 /**
 422  * Really get a message
 423  * @param $key String: key to get.
 424  * @param $args
 425  * @param $useDB Boolean
 426  * @param $transform Boolean: Whether or not to transform the message.
 427  * @param $forContent Boolean
 428  * @return String: the requested message.
 429  */
 430 function wfMsgReal( $key, $args, $useDB = true, $forContent=false, $transform = true ) {
 431         wfProfileIn( __METHOD__ );
 432         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 433         $message = wfMsgReplaceArgs( $message, $args );
 434         wfProfileOut( __METHOD__ );
 435         return $message;
 436 }
 437
 438 /**
 439  * This function provides the message source for messages to be edited which are *not* stored in the database.
 440  * @param $key String:
 441  */
 442 function wfMsgWeirdKey ( $key ) {
 443         $source = wfMsgGetKey( $key, false, true, false );
 444         if ( wfEmptyMsg( $key, $source ) )
 445                 return "";
 446         else
 447                 return $source;
 448 }
 449
 450 /**
 451  * Fetch a message string value, but don't replace any keys yet.
 452  * @param string $key
 453  * @param bool $useDB
 454  * @param string $langcode Code of the language to get the message for, or
 455  *                         behaves as a content language switch if it is a
 456  *                         boolean.
 457  * @return string
 458  * @private
 459  */
 460 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 461         global $wgParser, $wgContLang, $wgMessageCache, $wgLang;
 462
 463         # If $wgMessageCache isn't initialised yet, try to return something sensible.
 464         if( is_object( $wgMessageCache ) ) {
 465                 $message = $wgMessageCache->get( $key, $useDB, $langCode );
 466                 if ( $transform ) {
 467                         $message = $wgMessageCache->transform( $message );
 468                 }
 469         } else {
 470                 if( $langCode === true ) {
 471                         $lang = &$wgContLang;
 472                 } elseif( $langCode === false ) {
 473                         $lang = &$wgLang;
 474                 } else {
 475                         $validCodes = array_keys( Language::getLanguageNames() );
 476                         if( in_array( $langCode, $validCodes ) ) {
 477                                 # $langcode corresponds to a valid language.
 478                                 $lang = Language::factory( $langCode );
 479                         } else {
 480                                 # $langcode is a string, but not a valid language code; use content language.
 481                                 $lang =& $wgContLang;
 482                                 wfDebug( 'Invalid language code passed to wfMsgGetKey, falling back to content language.' );
 483                         }
 484                 }
 485
 486                 # MessageCache::get() does this already, Language::getMessage() doesn't
 487                 # ISSUE: Should we try to handle "message/lang" here too?
 488                 $key = str_replace( ' ' , '_' , $wgContLang->lcfirst( $key ) );
 489
 490                 if( is_object( $lang ) ) {
 491                         $message = $lang->getMessage( $key );
 492                 } else {
 493                         $message = false;
 494                 }
 495         }
 496
 497         return $message;
 498 }
 499
 500 /**
 501  * Replace message parameter keys on the given formatted output.
 502  *
 503  * @param string $message
 504  * @param array $args
 505  * @return string
 506  * @private
 507  */
 508 function wfMsgReplaceArgs( $message, $args ) {
 509         # Fix windows line-endings
 510         # Some messages are split with explode("\n", $msg)
 511         $message = str_replace( "\r", '', $message );
 512
 513         // Replace arguments
 514         if ( count( $args ) ) {
 515                 if ( is_array( $args[0] ) ) {
 516                         $args = array_values( $args[0] );
 517                 }
 518                 $replacementKeys = array();
 519                 foreach( $args as $n => $param ) {
 520                         $replacementKeys['$' . ($n + 1)] = $param;
 521                 }
 522                 $message = strtr( $message, $replacementKeys );
 523         }
 524
 525         return $message;
 526 }
 527
 528 /**
 529  * Return an HTML-escaped version of a message.
 530  * Parameter replacements, if any, are done *after* the HTML-escaping,
 531  * so parameters may contain HTML (eg links or form controls). Be sure
 532  * to pre-escape them if you really do want plaintext, or just wrap
 533  * the whole thing in htmlspecialchars().
 534  *
 535  * @param string $key
 536  * @param string ... parameters
 537  * @return string
 538  */
 539 function wfMsgHtml( $key ) {
 540         $args = func_get_args();
 541         array_shift( $args );
 542         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 543 }
 544
 545 /**
 546  * Return an HTML version of message
 547  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 548  * so parameters may contain HTML (eg links or form controls). Be sure
 549  * to pre-escape them if you really do want plaintext, or just wrap
 550  * the whole thing in htmlspecialchars().
 551  *
 552  * @param string $key
 553  * @param string ... parameters
 554  * @return string
 555  */
 556 function wfMsgWikiHtml( $key ) {
 557         global $wgOut;
 558         $args = func_get_args();
 559         array_shift( $args );
 560         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 561 }
 562
 563 /**
 564  * Returns message in the requested format
 565  * @param string $key Key of the message
 566  * @param array $options Processing rules:
 567  *  <i>parse</i>: parses wikitext to html
 568  *  <i>parseinline</i>: parses wikitext to html and removes the surrounding p's added by parser or tidy
 569  *  <i>escape</i>: filters message through htmlspecialchars
 570  *  <i>escapenoentities</i>: same, but allows entity references like &nbsp; through
 571  *  <i>replaceafter</i>: parameters are substituted after parsing or escaping
 572  *  <i>parsemag</i>: transform the message using magic phrases
 573  *  <i>content</i>: fetch message for content language instead of interface
 574  *  <i>language</i>: language code to fetch message for (overriden by <i>content</i>), its behaviour
 575  *                   with parser, parseinline and parsemag is undefined.
 576  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 577  */
 578 function wfMsgExt( $key, $options ) {
 579         global $wgOut, $wgParser;
 580
 581         $args = func_get_args();
 582         array_shift( $args );
 583         array_shift( $args );
 584
 585         if( !is_array($options) ) {
 586                 $options = array($options);
 587         }
 588
 589         if( in_array('content', $options) ) {
 590                 $forContent = true;
 591                 $langCode = true;
 592         } elseif( array_key_exists('language', $options) ) {
 593                 $forContent = false;
 594                 $langCode = $options['language'];
 595                 $validCodes = array_keys( Language::getLanguageNames() );
 596                 if( !in_array($options['language'], $validCodes) ) {
 597                         # Fallback to en, instead of whatever interface language we might have
 598                         $langCode = 'en';
 599                 }
 600         } else {
 601                 $forContent = false;
 602                 $langCode = false;
 603         }
 604
 605         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 606
 607         if( !in_array('replaceafter', $options) ) {
 608                 $string = wfMsgReplaceArgs( $string, $args );
 609         }
 610
 611         if( in_array('parse', $options) ) {
 612                 $string = $wgOut->parse( $string, true, !$forContent );
 613         } elseif ( in_array('parseinline', $options) ) {
 614                 $string = $wgOut->parse( $string, true, !$forContent );
 615                 $m = array();
 616                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 617                         $string = $m[1];
 618                 }
 619         } elseif ( in_array('parsemag', $options) ) {
 620                 global $wgMessageCache;
 621                 if ( isset( $wgMessageCache ) ) {
 622                         $string = $wgMessageCache->transform( $string, !$forContent );
 623                 }
 624         }
 625
 626         if ( in_array('escape', $options) ) {
 627                 $string = htmlspecialchars ( $string );
 628         } elseif ( in_array( 'escapenoentities', $options ) ) {
 629                 $string = htmlspecialchars( $string );
 630                 $string = str_replace( '&amp;', '&', $string );
 631                 $string = Sanitizer::normalizeCharReferences( $string );
 632         }
 633
 634         if( in_array('replaceafter', $options) ) {
 635                 $string = wfMsgReplaceArgs( $string, $args );
 636         }
 637
 638         return $string;
 639 }
 640
 641
 642 /**
 643  * Just like exit() but makes a note of it.
 644  * Commits open transactions except if the error parameter is set
 645  *
 646  * @deprecated Please return control to the caller or throw an exception
 647  */
 648 function wfAbruptExit( $error = false ){
 649         static $called = false;
 650         if ( $called ){
 651                 exit( -1 );
 652         }
 653         $called = true;
 654
 655         $bt = wfDebugBacktrace();
 656         if( $bt ) {
 657                 for($i = 0; $i < count($bt) ; $i++){
 658                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 659                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 660                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 661                 }
 662         } else {
 663                 wfDebug('WARNING: Abrupt exit\n');
 664         }
 665
 666         wfLogProfilingData();
 667
 668         if ( !$error ) {
 669                 wfGetLB()->closeAll();
 670         }
 671         exit( -1 );
 672 }
 673
 674 /**
 675  * @deprecated Please return control the caller or throw an exception
 676  */
 677 function wfErrorExit() {
 678         wfAbruptExit( true );
 679 }
 680
 681 /**
 682  * Print a simple message and die, returning nonzero to the shell if any.
 683  * Plain die() fails to return nonzero to the shell if you pass a string.
 684  * @param string $msg
 685  */
 686 function wfDie( $msg='' ) {
 687         echo $msg;
 688         die( 1 );
 689 }
 690
 691 /**
 692  * Throw a debugging exception. This function previously once exited the process,
 693  * but now throws an exception instead, with similar results.
 694  *
 695  * @param string $msg Message shown when dieing.
 696  */
 697 function wfDebugDieBacktrace( $msg = '' ) {
 698         throw new MWException( $msg );
 699 }
 700
 701 /**
 702  * Fetch server name for use in error reporting etc.
 703  * Use real server name if available, so we know which machine
 704  * in a server farm generated the current page.
 705  * @return string
 706  */
 707 function wfHostname() {
 708         if ( function_exists( 'posix_uname' ) ) {
 709                 // This function not present on Windows
 710                 $uname = @posix_uname();
 711         } else {
 712                 $uname = false;
 713         }
 714         if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 715                 return $uname['nodename'];
 716         } else {
 717                 # This may be a virtual server.
 718                 return $_SERVER['SERVER_NAME'];
 719         }
 720 }
 721
 722         /**
 723          * Returns a HTML comment with the elapsed time since request.
 724          * This method has no side effects.
 725          * @return string
 726          */
 727         function wfReportTime() {
 728                 global $wgRequestTime, $wgShowHostnames;
 729
 730                 $now = wfTime();
 731                 $elapsed = $now - $wgRequestTime;
 732
 733                 return $wgShowHostnames
 734                         ? sprintf( "<!-- Served by %s in %01.3f secs. -->", wfHostname(), $elapsed )
 735                         : sprintf( "<!-- Served in %01.3f secs. -->", $elapsed );
 736         }
 737
 738 /**
 739  * Safety wrapper for debug_backtrace().
 740  *
 741  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 742  * murky circumstances, which may be triggered in part by stub objects
 743  * or other fancy talkin'.
 744  *
 745  * Will return an empty array if Zend Optimizer is detected, otherwise
 746  * the output from debug_backtrace() (trimmed).
 747  *
 748  * @return array of backtrace information
 749  */
 750 function wfDebugBacktrace() {
 751         if( extension_loaded( 'Zend Optimizer' ) ) {
 752                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 753                 return array();
 754         } else {
 755                 return array_slice( debug_backtrace(), 1 );
 756         }
 757 }
 758
 759 function wfBacktrace() {
 760         global $wgCommandLineMode;
 761
 762         if ( $wgCommandLineMode ) {
 763                 $msg = '';
 764         } else {
 765                 $msg = "<ul>\n";
 766         }
 767         $backtrace = wfDebugBacktrace();
 768         foreach( $backtrace as $call ) {
 769                 if( isset( $call['file'] ) ) {
 770                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 771                         $file = $f[count($f)-1];
 772                 } else {
 773                         $file = '-';
 774                 }
 775                 if( isset( $call['line'] ) ) {
 776                         $line = $call['line'];
 777                 } else {
 778                         $line = '-';
 779                 }
 780                 if ( $wgCommandLineMode ) {
 781                         $msg .= "$file line $line calls ";
 782                 } else {
 783                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 784                 }
 785                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 786                 $msg .= $call['function'] . '()';
 787
 788                 if ( $wgCommandLineMode ) {
 789                         $msg .= "\n";
 790                 } else {
 791                         $msg .= "</li>\n";
 792                 }
 793         }
 794         if ( $wgCommandLineMode ) {
 795                 $msg .= "\n";
 796         } else {
 797                 $msg .= "</ul>\n";
 798         }
 799
 800         return $msg;
 801 }
 802
 803
 804 /* Some generic result counters, pulled out of SearchEngine */
 805
 806
 807 /**
 808  * @todo document
 809  */
 810 function wfShowingResults( $offset, $limit ) {
 811         global $wgLang;
 812         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 813 }
 814
 815 /**
 816  * @todo document
 817  */
 818 function wfShowingResultsNum( $offset, $limit, $num ) {
 819         global $wgLang;
 820         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 821 }
 822
 823 /**
 824  * @todo document
 825  */
 826 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 827         global $wgLang;
 828         $fmtLimit = $wgLang->formatNum( $limit );
 829         $prev = wfMsg( 'prevn', $fmtLimit );
 830         $next = wfMsg( 'nextn', $fmtLimit );
 831
 832         if( is_object( $link ) ) {
 833                 $title =& $link;
 834         } else {
 835                 $title = Title::newFromText( $link );
 836                 if( is_null( $title ) ) {
 837                         return false;
 838                 }
 839         }
 840
 841         if ( 0 != $offset ) {
 842                 $po = $offset - $limit;
 843                 if ( $po < 0 ) { $po = 0; }
 844                 $q = "limit={$limit}&offset={$po}";
 845                 if ( '' != $query ) { $q .= '&'.$query; }
 846                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
 847         } else { $plink = $prev; }
 848
 849         $no = $offset + $limit;
 850         $q = 'limit='.$limit.'&offset='.$no;
 851         if ( '' != $query ) { $q .= '&'.$query; }
 852
 853         if ( $atend ) {
 854                 $nlink = $next;
 855         } else {
 856                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
 857         }
 858         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 859           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 860           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 861           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 862           wfNumLink( $offset, 500, $title, $query );
 863
 864         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 865 }
 866
 867 /**
 868  * @todo document
 869  */
 870 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 871         global $wgLang;
 872         if ( '' == $query ) { $q = ''; }
 873         else { $q = $query.'&'; }
 874         $q .= 'limit='.$limit.'&offset='.$offset;
 875
 876         $fmtLimit = $wgLang->formatNum( $limit );
 877         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-numlink\">{$fmtLimit}</a>";
 878         return $s;
 879 }
 880
 881 /**
 882  * @todo document
 883  * @todo FIXME: we may want to blacklist some broken browsers
 884  *
 885  * @return bool Whereas client accept gzip compression
 886  */
 887 function wfClientAcceptsGzip() {
 888         global $wgUseGzip;
 889         if( $wgUseGzip ) {
 890                 # FIXME: we may want to blacklist some broken browsers
 891                 $m = array();
 892                 if( preg_match(
 893                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 894                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 895                         $m ) ) {
 896                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 897                         wfDebug( " accepts gzip\n" );
 898                         return true;
 899                 }
 900         }
 901         return false;
 902 }
 903
 904 /**
 905  * Obtain the offset and limit values from the request string;
 906  * used in special pages
 907  *
 908  * @param $deflimit Default limit if none supplied
 909  * @param $optionname Name of a user preference to check against
 910  * @return array
 911  *
 912  */
 913 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 914         global $wgRequest;
 915         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 916 }
 917
 918 /**
 919  * Escapes the given text so that it may be output using addWikiText()
 920  * without any linking, formatting, etc. making its way through. This
 921  * is achieved by substituting certain characters with HTML entities.
 922  * As required by the callers, <nowiki> is not used. It currently does
 923  * not filter out characters which have special meaning only at the
 924  * start of a line, such as "*".
 925  *
 926  * @param string $text Text to be escaped
 927  */
 928 function wfEscapeWikiText( $text ) {
 929         $text = str_replace(
 930                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
 931                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
 932                 htmlspecialchars($text) );
 933         return $text;
 934 }
 935
 936 /**
 937  * @todo document
 938  */
 939 function wfQuotedPrintable( $string, $charset = '' ) {
 940         # Probably incomplete; see RFC 2045
 941         if( empty( $charset ) ) {
 942                 global $wgInputEncoding;
 943                 $charset = $wgInputEncoding;
 944         }
 945         $charset = strtoupper( $charset );
 946         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 947
 948         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 949         $replace = $illegal . '\t ?_';
 950         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 951         $out = "=?$charset?Q?";
 952         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 953         $out .= '?=';
 954         return $out;
 955 }
 956
 957
 958 /**
 959  * @todo document
 960  * @return float
 961  */
 962 function wfTime() {
 963         return microtime(true);
 964 }
 965
 966 /**
 967  * Sets dest to source and returns the original value of dest
 968  * If source is NULL, it just returns the value, it doesn't set the variable
 969  */
 970 function wfSetVar( &$dest, $source ) {
 971         $temp = $dest;
 972         if ( !is_null( $source ) ) {
 973                 $dest = $source;
 974         }
 975         return $temp;
 976 }
 977
 978 /**
 979  * As for wfSetVar except setting a bit
 980  */
 981 function wfSetBit( &$dest, $bit, $state = true ) {
 982         $temp = (bool)($dest & $bit );
 983         if ( !is_null( $state ) ) {
 984                 if ( $state ) {
 985                         $dest |= $bit;
 986                 } else {
 987                         $dest &= ~$bit;
 988                 }
 989         }
 990         return $temp;
 991 }
 992
 993 /**
 994  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 995  * "days=7&limit=100". Options in the first array override options in the second.
 996  * Options set to "" will not be output.
 997  */
 998 function wfArrayToCGI( $array1, $array2 = NULL )
 999 {
1000         if ( !is_null( $array2 ) ) {
1001                 $array1 = $array1 + $array2;
1002         }
1003
1004         $cgi = '';
1005         foreach ( $array1 as $key => $value ) {
1006                 if ( '' !== $value ) {
1007                         if ( '' != $cgi ) {
1008                                 $cgi .= '&';
1009                         }
1010                         if(is_array($value))
1011                         {
1012                                 $firstTime = true;
1013                                 foreach($value as $v)
1014                                 {
1015                                         $cgi .= ($firstTime ? '' : '&') .
1016                                                 urlencode( $key . '[]' ) . '=' .
1017                                                 urlencode( $v );
1018                                         $firstTime = false;
1019                                 }
1020                         }
1021                         else
1022                                 $cgi .= urlencode( $key ) . '=' .
1023                                         urlencode( $value );
1024                 }
1025         }
1026         return $cgi;
1027 }
1028
1029 /**
1030  * Append a query string to an existing URL, which may or may not already
1031  * have query string parameters already. If so, they will be combined.
1032  *
1033  * @param string $url
1034  * @param string $query
1035  * @return string
1036  */
1037 function wfAppendQuery( $url, $query ) {
1038         if( $query != '' ) {
1039                 if( false === strpos( $url, '?' ) ) {
1040                         $url .= '?';
1041                 } else {
1042                         $url .= '&';
1043                 }
1044                 $url .= $query;
1045         }
1046         return $url;
1047 }
1048
1049 /**
1050  * Expand a potentially local URL to a fully-qualified URL.
1051  * Assumes $wgServer is correct. :)
1052  * @param string $url, either fully-qualified or a local path + query
1053  * @return string Fully-qualified URL
1054  */
1055 function wfExpandUrl( $url ) {
1056         if( substr( $url, 0, 1 ) == '/' ) {
1057                 global $wgServer;
1058                 return $wgServer . $url;
1059         } else {
1060                 return $url;
1061         }
1062 }
1063
1064 /**
1065  * This is obsolete, use SquidUpdate::purge()
1066  * @deprecated
1067  */
1068 function wfPurgeSquidServers ($urlArr) {
1069         SquidUpdate::purge( $urlArr );
1070 }
1071
1072 /**
1073  * Windows-compatible version of escapeshellarg()
1074  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1075  * function puts single quotes in regardless of OS
1076  */
1077 function wfEscapeShellArg( ) {
1078         $args = func_get_args();
1079         $first = true;
1080         $retVal = '';
1081         foreach ( $args as $arg ) {
1082                 if ( !$first ) {
1083                         $retVal .= ' ';
1084                 } else {
1085                         $first = false;
1086                 }
1087
1088                 if ( wfIsWindows() ) {
1089                         // Escaping for an MSVC-style command line parser
1090                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1091                         // Double the backslashes before any double quotes. Escape the double quotes.
1092                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1093                         $arg = '';
1094                         $delim = false;
1095                         foreach ( $tokens as $token ) {
1096                                 if ( $delim ) {
1097                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1098                                 } else {
1099                                         $arg .= $token;
1100                                 }
1101                                 $delim = !$delim;
1102                         }
1103                         // Double the backslashes before the end of the string, because
1104                         // we will soon add a quote
1105                         $m = array();
1106                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1107                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1108                         }
1109
1110                         // Add surrounding quotes
1111                         $retVal .= '"' . $arg . '"';
1112                 } else {
1113                         $retVal .= escapeshellarg( $arg );
1114                 }
1115         }
1116         return $retVal;
1117 }
1118
1119 /**
1120  * wfMerge attempts to merge differences between three texts.
1121  * Returns true for a clean merge and false for failure or a conflict.
1122  */
1123 function wfMerge( $old, $mine, $yours, &$result ){
1124         global $wgDiff3;
1125
1126         # This check may also protect against code injection in
1127         # case of broken installations.
1128         if(! file_exists( $wgDiff3 ) ){
1129                 wfDebug( "diff3 not found\n" );
1130                 return false;
1131         }
1132
1133         # Make temporary files
1134         $td = wfTempDir();
1135         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1136         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1137         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1138
1139         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1140         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1141         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1142
1143         # Check for a conflict
1144         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1145           wfEscapeShellArg( $mytextName ) . ' ' .
1146           wfEscapeShellArg( $oldtextName ) . ' ' .
1147           wfEscapeShellArg( $yourtextName );
1148         $handle = popen( $cmd, 'r' );
1149
1150         if( fgets( $handle, 1024 ) ){
1151                 $conflict = true;
1152         } else {
1153                 $conflict = false;
1154         }
1155         pclose( $handle );
1156
1157         # Merge differences
1158         $cmd = $wgDiff3 . ' -a -e --merge ' .
1159           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1160         $handle = popen( $cmd, 'r' );
1161         $result = '';
1162         do {
1163                 $data = fread( $handle, 8192 );
1164                 if ( strlen( $data ) == 0 ) {
1165                         break;
1166                 }
1167                 $result .= $data;
1168         } while ( true );
1169         pclose( $handle );
1170         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1171
1172         if ( $result === '' && $old !== '' && $conflict == false ) {
1173                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1174                 $conflict = true;
1175         }
1176         return ! $conflict;
1177 }
1178
1179 /**
1180  * @todo document
1181  */
1182 function wfVarDump( $var ) {
1183         global $wgOut;
1184         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1185         if ( headers_sent() || !@is_object( $wgOut ) ) {
1186                 print $s;
1187         } else {
1188                 $wgOut->addHTML( $s );
1189         }
1190 }
1191
1192 /**
1193  * Provide a simple HTTP error.
1194  */
1195 function wfHttpError( $code, $label, $desc ) {
1196         global $wgOut;
1197         $wgOut->disable();
1198         header( "HTTP/1.0 $code $label" );
1199         header( "Status: $code $label" );
1200         $wgOut->sendCacheControl();
1201
1202         header( 'Content-type: text/html; charset=utf-8' );
1203         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1204                 "<html><head><title>" .
1205                 htmlspecialchars( $label ) .
1206                 "</title></head><body><h1>" .
1207                 htmlspecialchars( $label ) .
1208                 "</h1><p>" .
1209                 nl2br( htmlspecialchars( $desc ) ) .
1210                 "</p></body></html>\n";
1211 }
1212
1213 /**
1214  * Clear away any user-level output buffers, discarding contents.
1215  *
1216  * Suitable for 'starting afresh', for instance when streaming
1217  * relatively large amounts of data without buffering, or wanting to
1218  * output image files without ob_gzhandler's compression.
1219  *
1220  * The optional $resetGzipEncoding parameter controls suppression of
1221  * the Content-Encoding header sent by ob_gzhandler; by default it
1222  * is left. See comments for wfClearOutputBuffers() for why it would
1223  * be used.
1224  *
1225  * Note that some PHP configuration options may add output buffer
1226  * layers which cannot be removed; these are left in place.
1227  *
1228  * @param bool $resetGzipEncoding
1229  */
1230 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1231         if( $resetGzipEncoding ) {
1232                 // Suppress Content-Encoding and Content-Length
1233                 // headers from 1.10+s wfOutputHandler
1234                 global $wgDisableOutputCompression;
1235                 $wgDisableOutputCompression = true;
1236         }
1237         while( $status = ob_get_status() ) {
1238                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1239                         // Probably from zlib.output_compression or other
1240                         // PHP-internal setting which can't be removed.
1241                         //
1242                         // Give up, and hope the result doesn't break
1243                         // output behavior.
1244                         break;
1245                 }
1246                 if( !ob_end_clean() ) {
1247                         // Could not remove output buffer handler; abort now
1248                         // to avoid getting in some kind of infinite loop.
1249                         break;
1250                 }
1251                 if( $resetGzipEncoding ) {
1252                         if( $status['name'] == 'ob_gzhandler' ) {
1253                                 // Reset the 'Content-Encoding' field set by this handler
1254                                 // so we can start fresh.
1255                                 header( 'Content-Encoding:' );
1256                         }
1257                 }
1258         }
1259 }
1260
1261 /**
1262  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1263  *
1264  * Clear away output buffers, but keep the Content-Encoding header
1265  * produced by ob_gzhandler, if any.
1266  *
1267  * This should be used for HTTP 304 responses, where you need to
1268  * preserve the Content-Encoding header of the real result, but
1269  * also need to suppress the output of ob_gzhandler to keep to spec
1270  * and avoid breaking Firefox in rare cases where the headers and
1271  * body are broken over two packets.
1272  */
1273 function wfClearOutputBuffers() {
1274         wfResetOutputBuffers( false );
1275 }
1276
1277 /**
1278  * Converts an Accept-* header into an array mapping string values to quality
1279  * factors
1280  */
1281 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1282         # No arg means accept anything (per HTTP spec)
1283         if( !$accept ) {
1284                 return array( $def => 1.0 );
1285         }
1286
1287         $prefs = array();
1288
1289         $parts = explode( ',', $accept );
1290
1291         foreach( $parts as $part ) {
1292                 # FIXME: doesn't deal with params like 'text/html; level=1'
1293                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1294                 $match = array();
1295                 if( !isset( $qpart ) ) {
1296                         $prefs[$value] = 1.0;
1297                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1298                         $prefs[$value] = floatval($match[1]);
1299                 }
1300         }
1301
1302         return $prefs;
1303 }
1304
1305 /**
1306  * Checks if a given MIME type matches any of the keys in the given
1307  * array. Basic wildcards are accepted in the array keys.
1308  *
1309  * Returns the matching MIME type (or wildcard) if a match, otherwise
1310  * NULL if no match.
1311  *
1312  * @param string $type
1313  * @param array $avail
1314  * @return string
1315  * @private
1316  */
1317 function mimeTypeMatch( $type, $avail ) {
1318         if( array_key_exists($type, $avail) ) {
1319                 return $type;
1320         } else {
1321                 $parts = explode( '/', $type );
1322                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1323                         return $parts[0] . '/*';
1324                 } elseif( array_key_exists( '*/*', $avail ) ) {
1325                         return '*/*';
1326                 } else {
1327                         return NULL;
1328                 }
1329         }
1330 }
1331
1332 /**
1333  * Returns the 'best' match between a client's requested internet media types
1334  * and the server's list of available types. Each list should be an associative
1335  * array of type to preference (preference is a float between 0.0 and 1.0).
1336  * Wildcards in the types are acceptable.
1337  *
1338  * @param array $cprefs Client's acceptable type list
1339  * @param array $sprefs Server's offered types
1340  * @return string
1341  *
1342  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1343  * XXX: generalize to negotiate other stuff
1344  */
1345 function wfNegotiateType( $cprefs, $sprefs ) {
1346         $combine = array();
1347
1348         foreach( array_keys($sprefs) as $type ) {
1349                 $parts = explode( '/', $type );
1350                 if( $parts[1] != '*' ) {
1351                         $ckey = mimeTypeMatch( $type, $cprefs );
1352                         if( $ckey ) {
1353                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1354                         }
1355                 }
1356         }
1357
1358         foreach( array_keys( $cprefs ) as $type ) {
1359                 $parts = explode( '/', $type );
1360                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1361                         $skey = mimeTypeMatch( $type, $sprefs );
1362                         if( $skey ) {
1363                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1364                         }
1365                 }
1366         }
1367
1368         $bestq = 0;
1369         $besttype = NULL;
1370
1371         foreach( array_keys( $combine ) as $type ) {
1372                 if( $combine[$type] > $bestq ) {
1373                         $besttype = $type;
1374                         $bestq = $combine[$type];
1375                 }
1376         }
1377
1378         return $besttype;
1379 }
1380
1381 /**
1382  * Array lookup
1383  * Returns an array where the values in the first array are replaced by the
1384  * values in the second array with the corresponding keys
1385  *
1386  * @return array
1387  */
1388 function wfArrayLookup( $a, $b ) {
1389         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1390 }
1391
1392 /**
1393  * Convenience function; returns MediaWiki timestamp for the present time.
1394  * @return string
1395  */
1396 function wfTimestampNow() {
1397         # return NOW
1398         return wfTimestamp( TS_MW, time() );
1399 }
1400
1401 /**
1402  * Reference-counted warning suppression
1403  */
1404 function wfSuppressWarnings( $end = false ) {
1405         static $suppressCount = 0;
1406         static $originalLevel = false;
1407
1408         if ( $end ) {
1409                 if ( $suppressCount ) {
1410                         --$suppressCount;
1411                         if ( !$suppressCount ) {
1412                                 error_reporting( $originalLevel );
1413                         }
1414                 }
1415         } else {
1416                 if ( !$suppressCount ) {
1417                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1418                 }
1419                 ++$suppressCount;
1420         }
1421 }
1422
1423 /**
1424  * Restore error level to previous value
1425  */
1426 function wfRestoreWarnings() {
1427         wfSuppressWarnings( true );
1428 }
1429
1430 # Autodetect, convert and provide timestamps of various types
1431
1432 /**
1433  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1434  */
1435 define('TS_UNIX', 0);
1436
1437 /**
1438  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1439  */
1440 define('TS_MW', 1);
1441
1442 /**
1443  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1444  */
1445 define('TS_DB', 2);
1446
1447 /**
1448  * RFC 2822 format, for E-mail and HTTP headers
1449  */
1450 define('TS_RFC2822', 3);
1451
1452 /**
1453  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1454  *
1455  * This is used by Special:Export
1456  */
1457 define('TS_ISO_8601', 4);
1458
1459 /**
1460  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1461  *
1462  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1463  *       DateTime tag and page 36 for the DateTimeOriginal and
1464  *       DateTimeDigitized tags.
1465  */
1466 define('TS_EXIF', 5);
1467
1468 /**
1469  * Oracle format time.
1470  */
1471 define('TS_ORACLE', 6);
1472
1473 /**
1474  * Postgres format time.
1475  */
1476 define('TS_POSTGRES', 7);
1477
1478 /**
1479  * @param mixed $outputtype A timestamp in one of the supported formats, the
1480  *                          function will autodetect which format is supplied
1481  *                          and act accordingly.
1482  * @return string Time in the format specified in $outputtype
1483  */
1484 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1485         $uts = 0;
1486         $da = array();
1487         if ($ts==0) {
1488                 $uts=time();
1489         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1490                 # TS_DB
1491         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1492                 # TS_EXIF
1493         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1494                 # TS_MW
1495         } elseif (preg_match('/^\d{1,13}$/D',$ts)) {
1496                 # TS_UNIX
1497                 $uts = $ts;
1498         } elseif (preg_match('/^\d{1,2}-...-\d\d(?:\d\d)? \d\d\.\d\d\.\d\d/', $ts)) {
1499                 # TS_ORACLE
1500                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1501                                 str_replace("+00:00", "UTC", $ts)));
1502         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1503                 # TS_ISO_8601
1504         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1505                 # TS_POSTGRES
1506         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1507                 # TS_POSTGRES
1508         } else {
1509                 # Bogus value; fall back to the epoch...
1510                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1511                 $uts = 0;
1512         }
1513
1514         if (count( $da ) ) {
1515                 // Warning! gmmktime() acts oddly if the month or day is set to 0
1516                 // We may want to handle that explicitly at some point
1517                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1518                         (int)$da[2],(int)$da[3],(int)$da[1]);
1519         }
1520
1521         switch($outputtype) {
1522                 case TS_UNIX:
1523                         return $uts;
1524                 case TS_MW:
1525                         return gmdate( 'YmdHis', $uts );
1526                 case TS_DB:
1527                         return gmdate( 'Y-m-d H:i:s', $uts );
1528                 case TS_ISO_8601:
1529                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1530                 // This shouldn't ever be used, but is included for completeness
1531                 case TS_EXIF:
1532                         return gmdate(  'Y:m:d H:i:s', $uts );
1533                 case TS_RFC2822:
1534                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1535                 case TS_ORACLE:
1536                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1537                 case TS_POSTGRES:
1538                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1539                 default:
1540                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1541         }
1542 }
1543
1544 /**
1545  * Return a formatted timestamp, or null if input is null.
1546  * For dealing with nullable timestamp columns in the database.
1547  * @param int $outputtype
1548  * @param string $ts
1549  * @return string
1550  */
1551 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1552         if( is_null( $ts ) ) {
1553                 return null;
1554         } else {
1555                 return wfTimestamp( $outputtype, $ts );
1556         }
1557 }
1558
1559 /**
1560  * Check if the operating system is Windows
1561  *
1562  * @return bool True if it's Windows, False otherwise.
1563  */
1564 function wfIsWindows() {
1565         if (substr(php_uname(), 0, 7) == 'Windows') {
1566                 return true;
1567         } else {
1568                 return false;
1569         }
1570 }
1571
1572 /**
1573  * Swap two variables
1574  */
1575 function swap( &$x, &$y ) {
1576         $z = $x;
1577         $x = $y;
1578         $y = $z;
1579 }
1580
1581 function wfGetCachedNotice( $name ) {
1582         global $wgOut, $parserMemc;
1583         $fname = 'wfGetCachedNotice';
1584         wfProfileIn( $fname );
1585
1586         $needParse = false;
1587
1588         if( $name === 'default' ) {
1589                 // special case
1590                 global $wgSiteNotice;
1591                 $notice = $wgSiteNotice;
1592                 if( empty( $notice ) ) {
1593                         wfProfileOut( $fname );
1594                         return false;
1595                 }
1596         } else {
1597                 $notice = wfMsgForContentNoTrans( $name );
1598                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1599                         wfProfileOut( $fname );
1600                         return( false );
1601                 }
1602         }
1603
1604         $cachedNotice = $parserMemc->get( wfMemcKey( $name ) );
1605         if( is_array( $cachedNotice ) ) {
1606                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1607                         $notice = $cachedNotice['html'];
1608                 } else {
1609                         $needParse = true;
1610                 }
1611         } else {
1612                 $needParse = true;
1613         }
1614
1615         if( $needParse ) {
1616                 if( is_object( $wgOut ) ) {
1617                         $parsed = $wgOut->parse( $notice );
1618                         $parserMemc->set( wfMemcKey( $name ), array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1619                         $notice = $parsed;
1620                 } else {
1621                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1622                         $notice = '';
1623                 }
1624         }
1625
1626         wfProfileOut( $fname );
1627         return $notice;
1628 }
1629
1630 function wfGetNamespaceNotice() {
1631         global $wgTitle;
1632
1633         # Paranoia
1634         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1635                 return "";
1636
1637         $fname = 'wfGetNamespaceNotice';
1638         wfProfileIn( $fname );
1639
1640         $key = "namespacenotice-" . $wgTitle->getNsText();
1641         $namespaceNotice = wfGetCachedNotice( $key );
1642         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1643                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1644         } else {
1645                 $namespaceNotice = "";
1646         }
1647
1648         wfProfileOut( $fname );
1649         return $namespaceNotice;
1650 }
1651
1652 function wfGetSiteNotice() {
1653         global $wgUser, $wgSiteNotice;
1654         $fname = 'wfGetSiteNotice';
1655         wfProfileIn( $fname );
1656         $siteNotice = '';
1657
1658         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1659                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1660                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1661                 } else {
1662                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1663                         if( !$anonNotice ) {
1664                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1665                         } else {
1666                                 $siteNotice = $anonNotice;
1667                         }
1668                 }
1669                 if( !$siteNotice ) {
1670                         $siteNotice = wfGetCachedNotice( 'default' );
1671                 }
1672         }
1673
1674         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1675         wfProfileOut( $fname );
1676         return $siteNotice;
1677 }
1678
1679 /**
1680  * BC wrapper for MimeMagic::singleton()
1681  * @deprecated
1682  */
1683 function &wfGetMimeMagic() {
1684         return MimeMagic::singleton();
1685 }
1686
1687 /**
1688  * Tries to get the system directory for temporary files.
1689  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1690  * and if none are set /tmp is returned as the generic Unix default.
1691  *
1692  * NOTE: When possible, use the tempfile() function to create temporary
1693  * files to avoid race conditions on file creation, etc.
1694  *
1695  * @return string
1696  */
1697 function wfTempDir() {
1698         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1699                 $tmp = getenv( $var );
1700                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1701                         return $tmp;
1702                 }
1703         }
1704         # Hope this is Unix of some kind!
1705         return '/tmp';
1706 }
1707
1708 /**
1709  * Make directory, and make all parent directories if they don't exist
1710  */
1711 function wfMkdirParents( $fullDir, $mode = 0777 ) {
1712         if( strval( $fullDir ) === '' )
1713                 return true;
1714         if( file_exists( $fullDir ) )
1715                 return true;
1716
1717         # Go back through the paths to find the first directory that exists
1718         $currentDir = $fullDir;
1719         $createList = array();
1720         while ( strval( $currentDir ) !== '' && !file_exists( $currentDir ) ) {
1721                 # Strip trailing slashes
1722                 $currentDir = rtrim( $currentDir, '/\\' );
1723
1724                 # Add to create list
1725                 $createList[] = $currentDir;
1726
1727                 # Find next delimiter searching from the end
1728                 $p = max( strrpos( $currentDir, '/' ), strrpos( $currentDir, '\\' ) );
1729                 if ( $p === false ) {
1730                         $currentDir = false;
1731                 } else {
1732                         $currentDir = substr( $currentDir, 0, $p );
1733                 }
1734         }
1735
1736         if ( count( $createList ) == 0 ) {
1737                 # Directory specified already exists
1738                 return true;
1739         } elseif ( $currentDir === false ) {
1740                 # Went all the way back to root and it apparently doesn't exist
1741                 wfDebugLog( 'mkdir', "Root doesn't exist?\n" );
1742                 return false;
1743         }
1744         # Now go forward creating directories
1745         $createList = array_reverse( $createList );
1746
1747         # Is the parent directory writable?
1748         if ( $currentDir === '' ) {
1749                 $currentDir = '/';
1750         }
1751         if ( !is_writable( $currentDir ) ) {
1752                 wfDebugLog( 'mkdir', "Not writable: $currentDir\n" );
1753                 return false;
1754         }
1755
1756         foreach ( $createList as $dir ) {
1757                 # use chmod to override the umask, as suggested by the PHP manual
1758                 if ( !mkdir( $dir, $mode ) || !chmod( $dir, $mode ) ) {
1759                         wfDebugLog( 'mkdir', "Unable to create directory $dir\n" );
1760                         return false;
1761                 }
1762         }
1763         return true;
1764 }
1765
1766 /**
1767  * Increment a statistics counter
1768  */
1769 function wfIncrStats( $key ) {
1770         global $wgStatsMethod;
1771
1772         if( $wgStatsMethod == 'udp' ) {
1773                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
1774                 static $socket;
1775                 if (!$socket) {
1776                         $socket=socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
1777                         $statline="stats/{$wgDBname} - 1 1 1 1 1 -total\n";
1778                         socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1779                 }
1780                 $statline="stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
1781                 @socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1782         } elseif( $wgStatsMethod == 'cache' ) {
1783                 global $wgMemc;
1784                 $key = wfMemcKey( 'stats', $key );
1785                 if ( is_null( $wgMemc->incr( $key ) ) ) {
1786                         $wgMemc->add( $key, 1 );
1787                 }
1788         } else {
1789                 // Disabled
1790         }
1791 }
1792
1793 /**
1794  * @param mixed $nr The number to format
1795  * @param int $acc The number of digits after the decimal point, default 2
1796  * @param bool $round Whether or not to round the value, default true
1797  * @return float
1798  */
1799 function wfPercent( $nr, $acc = 2, $round = true ) {
1800         $ret = sprintf( "%.${acc}f", $nr );
1801         return $round ? round( $ret, $acc ) . '%' : "$ret%";
1802 }
1803
1804 /**
1805  * Appends to second array if $value differs from that in $default
1806  */
1807 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
1808         if ( is_null( $changed ) ) {
1809                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
1810         }
1811         if ( $default[$key] !== $value ) {
1812                 $changed[$key] = $value;
1813         }
1814 }
1815
1816 /**
1817  * Since wfMsg() and co suck, they don't return false if the message key they
1818  * looked up didn't exist but a XHTML string, this function checks for the
1819  * nonexistance of messages by looking at wfMsg() output
1820  *
1821  * @param $msg      The message key looked up
1822  * @param $wfMsgOut The output of wfMsg*()
1823  * @return bool
1824  */
1825 function wfEmptyMsg( $msg, $wfMsgOut ) {
1826         return $wfMsgOut === htmlspecialchars( "<$msg>" );
1827 }
1828
1829 /**
1830  * Find out whether or not a mixed variable exists in a string
1831  *
1832  * @param mixed  needle
1833  * @param string haystack
1834  * @return bool
1835  */
1836 function in_string( $needle, $str ) {
1837         return strpos( $str, $needle ) !== false;
1838 }
1839
1840 function wfSpecialList( $page, $details ) {
1841         global $wgContLang;
1842         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
1843         return $page . $details;
1844 }
1845
1846 /**
1847  * Returns a regular expression of url protocols
1848  *
1849  * @return string
1850  */
1851 function wfUrlProtocols() {
1852         global $wgUrlProtocols;
1853
1854         // Support old-style $wgUrlProtocols strings, for backwards compatibility
1855         // with LocalSettings files from 1.5
1856         if ( is_array( $wgUrlProtocols ) ) {
1857                 $protocols = array();
1858                 foreach ($wgUrlProtocols as $protocol)
1859                         $protocols[] = preg_quote( $protocol, '/' );
1860
1861                 return implode( '|', $protocols );
1862         } else {
1863                 return $wgUrlProtocols;
1864         }
1865 }
1866
1867 /**
1868  * Safety wrapper around ini_get() for boolean settings.
1869  * The values returned from ini_get() are pre-normalized for settings
1870  * set via php.ini or php_flag/php_admin_flag... but *not*
1871  * for those set via php_value/php_admin_value.
1872  *
1873  * It's fairly common for people to use php_value instead of php_flag,
1874  * which can leave you with an 'off' setting giving a false positive
1875  * for code that just takes the ini_get() return value as a boolean.
1876  *
1877  * To make things extra interesting, setting via php_value accepts
1878  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
1879  * Unrecognized values go false... again opposite PHP's own coercion
1880  * from string to bool.
1881  *
1882  * Luckily, 'properly' set settings will always come back as '0' or '1',
1883  * so we only have to worry about them and the 'improper' settings.
1884  *
1885  * I frickin' hate PHP... :P
1886  *
1887  * @param string $setting
1888  * @return bool
1889  */
1890 function wfIniGetBool( $setting ) {
1891         $val = ini_get( $setting );
1892         // 'on' and 'true' can't have whitespace around them, but '1' can.
1893         return strtolower( $val ) == 'on'
1894                 || strtolower( $val ) == 'true'
1895                 || strtolower( $val ) == 'yes'
1896                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
1897 }
1898
1899 /**
1900  * Execute a shell command, with time and memory limits mirrored from the PHP
1901  * configuration if supported.
1902  * @param $cmd Command line, properly escaped for shell.
1903  * @param &$retval optional, will receive the program's exit code.
1904  *                 (non-zero is usually failure)
1905  * @return collected stdout as a string (trailing newlines stripped)
1906  */
1907 function wfShellExec( $cmd, &$retval=null ) {
1908         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
1909
1910         if( wfIniGetBool( 'safe_mode' ) ) {
1911                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
1912                 $retval = 1;
1913                 return "Unable to run external programs in safe mode.";
1914         }
1915
1916         if ( php_uname( 's' ) == 'Linux' ) {
1917                 $time = intval( ini_get( 'max_execution_time' ) );
1918                 $mem = intval( $wgMaxShellMemory );
1919                 $filesize = intval( $wgMaxShellFileSize );
1920
1921                 if ( $time > 0 && $mem > 0 ) {
1922                         $script = "$IP/bin/ulimit4.sh";
1923                         if ( is_executable( $script ) ) {
1924                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
1925                         }
1926                 }
1927         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
1928                 # This is a hack to work around PHP's flawed invocation of cmd.exe
1929                 # http://news.php.net/php.internals/21796
1930                 $cmd = '"' . $cmd . '"';
1931         }
1932         wfDebug( "wfShellExec: $cmd\n" );
1933
1934         $retval = 1; // error by default?
1935         ob_start();
1936         passthru( $cmd, $retval );
1937         $output = ob_get_contents();
1938         ob_end_clean();
1939         return $output;
1940
1941 }
1942
1943 /**
1944  * This function works like "use VERSION" in Perl, the program will die with a
1945  * backtrace if the current version of PHP is less than the version provided
1946  *
1947  * This is useful for extensions which due to their nature are not kept in sync
1948  * with releases, and might depend on other versions of PHP than the main code
1949  *
1950  * Note: PHP might die due to parsing errors in some cases before it ever
1951  *       manages to call this function, such is life
1952  *
1953  * @see perldoc -f use
1954  *
1955  * @param mixed $version The version to check, can be a string, an integer, or
1956  *                       a float
1957  */
1958 function wfUsePHP( $req_ver ) {
1959         $php_ver = PHP_VERSION;
1960
1961         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
1962                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
1963 }
1964
1965 /**
1966  * This function works like "use VERSION" in Perl except it checks the version
1967  * of MediaWiki, the program will die with a backtrace if the current version
1968  * of MediaWiki is less than the version provided.
1969  *
1970  * This is useful for extensions which due to their nature are not kept in sync
1971  * with releases
1972  *
1973  * @see perldoc -f use
1974  *
1975  * @param mixed $version The version to check, can be a string, an integer, or
1976  *                       a float
1977  */
1978 function wfUseMW( $req_ver ) {
1979         global $wgVersion;
1980
1981         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
1982                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
1983 }
1984
1985 /**
1986  * @deprecated use StringUtils::escapeRegexReplacement
1987  */
1988 function wfRegexReplacement( $string ) {
1989         return StringUtils::escapeRegexReplacement( $string );
1990 }
1991
1992 /**
1993  * Return the final portion of a pathname.
1994  * Reimplemented because PHP5's basename() is buggy with multibyte text.
1995  * http://bugs.php.net/bug.php?id=33898
1996  *
1997  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
1998  * We'll consider it so always, as we don't want \s in our Unix paths either.
1999  *
2000  * @param string $path
2001  * @param string $suffix to remove if present
2002  * @return string
2003  */
2004 function wfBaseName( $path, $suffix='' ) {
2005         $encSuffix = ($suffix == '')
2006                 ? ''
2007                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2008         $matches = array();
2009         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2010                 return $matches[1];
2011         } else {
2012                 return '';
2013         }
2014 }
2015
2016 /**
2017  * Generate a relative path name to the given file.
2018  * May explode on non-matching case-insensitive paths,
2019  * funky symlinks, etc.
2020  *
2021  * @param string $path Absolute destination path including target filename
2022  * @param string $from Absolute source path, directory only
2023  * @return string
2024  */
2025 function wfRelativePath( $path, $from ) {
2026         // Normalize mixed input on Windows...
2027         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2028         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2029
2030         // Trim trailing slashes -- fix for drive root
2031         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2032         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2033
2034         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2035         $against = explode( DIRECTORY_SEPARATOR, $from );
2036
2037         if( $pieces[0] !== $against[0] ) {
2038                 // Non-matching Windows drive letters?
2039                 // Return a full path.
2040                 return $path;
2041         }
2042
2043         // Trim off common prefix
2044         while( count( $pieces ) && count( $against )
2045                 && $pieces[0] == $against[0] ) {
2046                 array_shift( $pieces );
2047                 array_shift( $against );
2048         }
2049
2050         // relative dots to bump us to the parent
2051         while( count( $against ) ) {
2052                 array_unshift( $pieces, '..' );
2053                 array_shift( $against );
2054         }
2055
2056         array_push( $pieces, wfBaseName( $path ) );
2057
2058         return implode( DIRECTORY_SEPARATOR, $pieces );
2059 }
2060
2061 /**
2062  * array_merge() does awful things with "numeric" indexes, including
2063  * string indexes when happen to look like integers. When we want
2064  * to merge arrays with arbitrary string indexes, we don't want our
2065  * arrays to be randomly corrupted just because some of them consist
2066  * of numbers.
2067  *
2068  * Fuck you, PHP. Fuck you in the ear!
2069  *
2070  * @param array $array1, [$array2, [...]]
2071  * @return array
2072  */
2073 function wfArrayMerge( $array1/* ... */ ) {
2074         $out = $array1;
2075         for( $i = 1; $i < func_num_args(); $i++ ) {
2076                 foreach( func_get_arg( $i ) as $key => $value ) {
2077                         $out[$key] = $value;
2078                 }
2079         }
2080         return $out;
2081 }
2082
2083 /**
2084  * Make a URL index, appropriate for the el_index field of externallinks.
2085  */
2086 function wfMakeUrlIndex( $url ) {
2087         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2088         wfSuppressWarnings();
2089         $bits = parse_url( $url );
2090         wfRestoreWarnings();
2091         if ( !$bits ) {
2092                 return false;
2093         }
2094         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2095         $delimiter = '';
2096         if ( in_array( $bits['scheme'] . '://' , $wgUrlProtocols ) ) {
2097                 $delimiter = '://';
2098         } elseif ( in_array( $bits['scheme'] .':' , $wgUrlProtocols ) ) {
2099                 $delimiter = ':';
2100                 // parse_url detects for news: and mailto: the host part of an url as path
2101                 // We have to correct this wrong detection
2102                 if ( isset ( $bits['path'] ) ) {
2103                         $bits['host'] = $bits['path'];
2104                         $bits['path'] = '';
2105                 }
2106         } else {
2107                 return false;
2108         }
2109
2110         // Reverse the labels in the hostname, convert to lower case
2111         // For emails reverse domainpart only
2112         if ( $bits['scheme'] == 'mailto' ) {
2113                 $mailparts = explode( '@', $bits['host'], 2 );
2114                 if ( count($mailparts) === 2 ) {
2115                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2116                 } else {
2117                         // No domain specified, don't mangle it
2118                         $domainpart = '';
2119                 }
2120                 $reversedHost = $domainpart . '@' . $mailparts[0];
2121         } else {
2122                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2123         }
2124         // Add an extra dot to the end
2125         // Why? Is it in wrong place in mailto links?
2126         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2127                 $reversedHost .= '.';
2128         }
2129         // Reconstruct the pseudo-URL
2130         $prot = $bits['scheme'];
2131         $index = "$prot$delimiter$reversedHost";
2132         // Leave out user and password. Add the port, path, query and fragment
2133         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
2134         if ( isset( $bits['path'] ) ) {
2135                 $index .= $bits['path'];
2136         } else {
2137                 $index .= '/';
2138         }
2139         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
2140         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
2141         return $index;
2142 }
2143
2144 /**
2145  * Do any deferred updates and clear the list
2146  * TODO: This could be in Wiki.php if that class made any sense at all
2147  */
2148 function wfDoUpdates()
2149 {
2150         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2151         foreach ( $wgDeferredUpdateList as $update ) {
2152                 $update->doUpdate();
2153         }
2154         foreach ( $wgPostCommitUpdateList as $update ) {
2155                 $update->doUpdate();
2156         }
2157         $wgDeferredUpdateList = array();
2158         $wgPostCommitUpdateList = array();
2159 }
2160
2161 /**
2162  * @deprecated use StringUtils::explodeMarkup
2163  */
2164 function wfExplodeMarkup( $separator, $text ) {
2165         return StringUtils::explodeMarkup( $separator, $text );
2166 }
2167
2168 /**
2169  * Convert an arbitrarily-long digit string from one numeric base
2170  * to another, optionally zero-padding to a minimum column width.
2171  *
2172  * Supports base 2 through 36; digit values 10-36 are represented
2173  * as lowercase letters a-z. Input is case-insensitive.
2174  *
2175  * @param $input string of digits
2176  * @param $sourceBase int 2-36
2177  * @param $destBase int 2-36
2178  * @param $pad int 1 or greater
2179  * @param $lowercase bool
2180  * @return string or false on invalid input
2181  */
2182 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2183         $input = strval( $input );
2184         if( $sourceBase < 2 ||
2185                 $sourceBase > 36 ||
2186                 $destBase < 2 ||
2187                 $destBase > 36 ||
2188                 $pad < 1 ||
2189                 $sourceBase != intval( $sourceBase ) ||
2190                 $destBase != intval( $destBase ) ||
2191                 $pad != intval( $pad ) ||
2192                 !is_string( $input ) ||
2193                 $input == '' ) {
2194                 return false;
2195         }
2196         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2197         $inDigits = array();
2198         $outChars = '';
2199
2200         // Decode and validate input string
2201         $input = strtolower( $input );
2202         for( $i = 0; $i < strlen( $input ); $i++ ) {
2203                 $n = strpos( $digitChars, $input{$i} );
2204                 if( $n === false || $n > $sourceBase ) {
2205                         return false;
2206                 }
2207                 $inDigits[] = $n;
2208         }
2209
2210         // Iterate over the input, modulo-ing out an output digit
2211         // at a time until input is gone.
2212         while( count( $inDigits ) ) {
2213                 $work = 0;
2214                 $workDigits = array();
2215
2216                 // Long division...
2217                 foreach( $inDigits as $digit ) {
2218                         $work *= $sourceBase;
2219                         $work += $digit;
2220
2221                         if( $work < $destBase ) {
2222                                 // Gonna need to pull another digit.
2223                                 if( count( $workDigits ) ) {
2224                                         // Avoid zero-padding; this lets us find
2225                                         // the end of the input very easily when
2226                                         // length drops to zero.
2227                                         $workDigits[] = 0;
2228                                 }
2229                         } else {
2230                                 // Finally! Actual division!
2231                                 $workDigits[] = intval( $work / $destBase );
2232
2233                                 // Isn't it annoying that most programming languages
2234                                 // don't have a single divide-and-remainder operator,
2235                                 // even though the CPU implements it that way?
2236                                 $work = $work % $destBase;
2237                         }
2238                 }
2239
2240                 // All that division leaves us with a remainder,
2241                 // which is conveniently our next output digit.
2242                 $outChars .= $digitChars[$work];
2243
2244                 // And we continue!
2245                 $inDigits = $workDigits;
2246         }
2247
2248         while( strlen( $outChars ) < $pad ) {
2249                 $outChars .= '0';
2250         }
2251
2252         return strrev( $outChars );
2253 }
2254
2255 /**
2256  * Create an object with a given name and an array of construct parameters
2257  * @param string $name
2258  * @param array $p parameters
2259  */
2260 function wfCreateObject( $name, $p ){
2261         $p = array_values( $p );
2262         switch ( count( $p ) ) {
2263                 case 0:
2264                         return new $name;
2265                 case 1:
2266                         return new $name( $p[0] );
2267                 case 2:
2268                         return new $name( $p[0], $p[1] );
2269                 case 3:
2270                         return new $name( $p[0], $p[1], $p[2] );
2271                 case 4:
2272                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2273                 case 5:
2274                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2275                 case 6:
2276                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2277                 default:
2278                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2279         }
2280 }
2281
2282 /**
2283  * Aliases for modularized functions
2284  */
2285 function wfGetHTTP( $url, $timeout = 'default' ) {
2286         return Http::get( $url, $timeout );
2287 }
2288 function wfIsLocalURL( $url ) {
2289         return Http::isLocalURL( $url );
2290 }
2291
2292 function wfHttpOnlySafe() {
2293         global $wgHttpOnlyBlacklist;
2294         if( !version_compare("5.2", PHP_VERSION, "<") )
2295                 return false;
2296
2297         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2298                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2299                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2300                                 return false;
2301                         }
2302                 }
2303         }
2304
2305         return true;
2306 }
2307
2308 /**
2309  * Initialise php session
2310  */
2311 function wfSetupSession() {
2312         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
2313         if( $wgSessionsInMemcached ) {
2314                 require_once( 'MemcachedSessions.php' );
2315         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2316                 # If it's left on 'user' or another setting from another
2317                 # application, it will end up failing. Try to recover.
2318                 ini_set ( 'session.save_handler', 'files' );
2319         }
2320         $httpOnlySafe = wfHttpOnlySafe();
2321         wfDebugLog( 'cookie',
2322                 'session_set_cookie_params: "' . implode( '", "',
2323                         array(
2324                                 0,
2325                                 $wgCookiePath,
2326                                 $wgCookieDomain,
2327                                 $wgCookieSecure,
2328                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2329         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2330                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2331         } else {
2332                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2333                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2334         }
2335         session_cache_limiter( 'private, must-revalidate' );
2336         wfSuppressWarnings();
2337         session_start();
2338         wfRestoreWarnings();
2339 }
2340
2341 /**
2342  * Get an object from the precompiled serialized directory
2343  *
2344  * @return mixed The variable on success, false on failure
2345  */
2346 function wfGetPrecompiledData( $name ) {
2347         global $IP;
2348
2349         $file = "$IP/serialized/$name";
2350         if ( file_exists( $file ) ) {
2351                 $blob = file_get_contents( $file );
2352                 if ( $blob ) {
2353                         return unserialize( $blob );
2354                 }
2355         }
2356         return false;
2357 }
2358
2359 function wfGetCaller( $level = 2 ) {
2360         $backtrace = wfDebugBacktrace();
2361         if ( isset( $backtrace[$level] ) ) {
2362                 return wfFormatStackFrame($backtrace[$level]);
2363         } else {
2364                 $caller = 'unknown';
2365         }
2366         return $caller;
2367 }
2368
2369 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2370 function wfGetAllCallers() {
2371         return implode('/', array_map('wfFormatStackFrame',array_reverse(wfDebugBacktrace())));
2372 }
2373
2374 /** Return a string representation of frame */
2375 function wfFormatStackFrame($frame) {
2376         return isset( $frame["class"] )?
2377                 $frame["class"]."::".$frame["function"]:
2378                 $frame["function"];
2379 }
2380
2381 /**
2382  * Get a cache key
2383  */
2384 function wfMemcKey( /*... */ ) {
2385         $args = func_get_args();
2386         $key = wfWikiID() . ':' . implode( ':', $args );
2387         return $key;
2388 }
2389
2390 /**
2391  * Get a cache key for a foreign DB
2392  */
2393 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2394         $args = array_slice( func_get_args(), 2 );
2395         if ( $prefix ) {
2396                 $key = "$db-$prefix:" . implode( ':', $args );
2397         } else {
2398                 $key = $db . ':' . implode( ':', $args );
2399         }
2400         return $key;
2401 }
2402
2403 /**
2404  * Get an ASCII string identifying this wiki
2405  * This is used as a prefix in memcached keys
2406  */
2407 function wfWikiID( $db = null ) {
2408         if( $db instanceof Database ) {
2409                 return $db->getWikiID();
2410         } else {
2411         global $wgDBprefix, $wgDBname;
2412                 if ( $wgDBprefix ) {
2413                         return "$wgDBname-$wgDBprefix";
2414                 } else {
2415                         return $wgDBname;
2416                 }
2417         }
2418 }
2419
2420 /**
2421  * Split a wiki ID into DB name and table prefix
2422  */
2423 function wfSplitWikiID( $wiki ) {
2424         $bits = explode( '-', $wiki, 2 );
2425         if ( count( $bits ) < 2 ) {
2426                 $bits[] = '';
2427         }
2428         return $bits;
2429 }
2430
2431 /*
2432  * Get a Database object.
2433  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2434  *                master (for write queries), DB_SLAVE for potentially lagged
2435  *                read queries, or an integer >= 0 for a particular server.
2436  *
2437  * @param mixed $groups Query groups. An array of group names that this query
2438  *              belongs to. May contain a single string if the query is only
2439  *              in one group.
2440  *
2441  * @param string $wiki The wiki ID, or false for the current wiki
2442  *
2443  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
2444  * will always return the same object, unless the underlying connection or load
2445  * balancer is manually destroyed.
2446  */
2447 function &wfGetDB( $db = DB_LAST, $groups = array(), $wiki = false ) {
2448         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2449 }
2450
2451 /**
2452  * Get a load balancer object.
2453  *
2454  * @param array $groups List of query groups
2455  * @param string $wiki Wiki ID, or false for the current wiki
2456  * @return LoadBalancer
2457  */
2458 function wfGetLB( $wiki = false ) {
2459         return wfGetLBFactory()->getMainLB( $wiki );
2460 }
2461
2462 /**
2463  * Get the load balancer factory object
2464  */
2465 function &wfGetLBFactory() {
2466         return LBFactory::singleton();
2467 }
2468
2469 /**
2470  * Find a file.
2471  * Shortcut for RepoGroup::singleton()->findFile()
2472  * @param mixed $title Title object or string. May be interwiki.
2473  * @param mixed $time Requested time for an archived image, or false for the
2474  *                    current version. An image object will be returned which
2475  *                    was created at the specified time.
2476  * @param mixed $flags FileRepo::FIND_ flags
2477  * @return File, or false if the file does not exist
2478  */
2479 function wfFindFile( $title, $time = false, $flags = 0 ) {
2480         return RepoGroup::singleton()->findFile( $title, $time, $flags );
2481 }
2482
2483 /**
2484  * Get an object referring to a locally registered file.
2485  * Returns a valid placeholder object if the file does not exist.
2486  */
2487 function wfLocalFile( $title ) {
2488         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2489 }
2490
2491 /**
2492  * Should low-performance queries be disabled?
2493  *
2494  * @return bool
2495  */
2496 function wfQueriesMustScale() {
2497         global $wgMiserMode;
2498         return $wgMiserMode
2499                 || ( SiteStats::pages() > 100000
2500                 && SiteStats::edits() > 1000000
2501                 && SiteStats::users() > 10000 );
2502 }
2503
2504 /**
2505  * Get the path to a specified script file, respecting file
2506  * extensions; this is a wrapper around $wgScriptExtension etc.
2507  *
2508  * @param string $script Script filename, sans extension
2509  * @return string
2510  */
2511 function wfScript( $script = 'index' ) {
2512         global $wgScriptPath, $wgScriptExtension;
2513         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
2514 }
2515
2516 /**
2517  * Convenience function converts boolean values into "true"
2518  * or "false" (string) values
2519  *
2520  * @param bool $value
2521  * @return string
2522  */
2523 function wfBoolToStr( $value ) {
2524         return $value ? 'true' : 'false';
2525 }
2526
2527 /**
2528  * Load an extension messages file
2529  *
2530  * @param string $extensionName Name of extension to load messages from\for.
2531  * @param string $langcode Language to load messages for, or false for default
2532  *                         behvaiour (en, content language and user language).
2533  */
2534 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
2535         global $wgExtensionMessagesFiles, $wgMessageCache, $wgLang, $wgContLang;
2536
2537         #For recording whether extension message files have been loaded in a given language.
2538         static $loaded = array();
2539
2540         if( !array_key_exists( $extensionName, $loaded ) ) {
2541                 $loaded[$extensionName] = array();
2542         }
2543
2544         if( !$langcode && !array_key_exists( '*', $loaded[$extensionName] ) ) {
2545                 # Just do en, content language and user language.
2546                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], false );
2547                 # Mark that they have been loaded.
2548                 $loaded[$extensionName]['en'] = true;
2549                 $loaded[$extensionName][$wgLang->getCode()] = true;
2550                 $loaded[$extensionName][$wgContLang->getCode()] = true;
2551                 # Mark that this part has been done to avoid weird if statements.
2552                 $loaded[$extensionName]['*'] = true;
2553         } elseif( is_string( $langcode ) && !array_key_exists( $langcode, $loaded[$extensionName] ) ) {
2554                 # Load messages for specified language.
2555                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], $langcode );
2556                 # Mark that they have been loaded.
2557                 $loaded[$extensionName][$langcode] = true;
2558         }
2559 }
2560
2561 /**
2562  * Get a platform-independent path to the null file, e.g.
2563  * /dev/null
2564  *
2565  * @return string
2566  */
2567 function wfGetNull() {
2568         return wfIsWindows()
2569                 ? 'NUL'
2570                 : '/dev/null';
2571 }
2572
2573 /**
2574  * Displays a maxlag error
2575  *
2576  * @param string $host Server that lags the most
2577  * @param int $lag Maxlag (actual)
2578  * @param int $maxLag Maxlag (requested)
2579  */
2580 function wfMaxlagError( $host, $lag, $maxLag ) {
2581         global $wgShowHostnames;
2582         header( 'HTTP/1.1 503 Service Unavailable' );
2583         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
2584         header( 'X-Database-Lag: ' . intval( $lag ) );
2585         header( 'Content-Type: text/plain' );
2586         if( $wgShowHostnames ) {
2587                 echo "Waiting for $host: $lag seconds lagged\n";
2588         } else {
2589                 echo "Waiting for a database server: $lag seconds lagged\n";
2590         }
2591 }
2592
2593 /**
2594  * Throws an E_USER_NOTICE saying that $function is deprecated
2595  * @param string $function
2596  * @return null
2597  */
2598 function wfDeprecated( $function ) {
2599         global $wgDebugLogFile;
2600         if ( !$wgDebugLogFile ) {
2601                 return;
2602         }
2603         $callers = wfDebugBacktrace();
2604         if( isset( $callers[2] ) ){
2605                 $callerfunc = $callers[2];
2606                 $callerfile = $callers[1];
2607                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ){
2608                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
2609                 } else {
2610                         $file = '(internal function)';
2611                 }
2612                 $func = '';
2613                 if( isset( $callerfunc['class'] ) )
2614                         $func .= $callerfunc['class'] . '::';
2615                 $func .= @$callerfunc['function'];
2616                 $msg = "Use of $function is deprecated. Called from $func in $file";
2617         } else {
2618                 $msg = "Use of $function is deprecated.";
2619         }
2620         wfDebug( "$msg\n" );
2621 }
2622
2623 /**
2624  * Sleep until the worst slave's replication lag is less than or equal to
2625  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
2626  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
2627  * a no-op if there are no slaves.
2628  *
2629  * Every time the function has to wait for a slave, it will print a message to
2630  * that effect (and then sleep for a little while), so it's probably not best
2631  * to use this outside maintenance scripts in its present form.
2632  *
2633  * @param int $maxLag
2634  * @return null
2635  */
2636 function wfWaitForSlaves( $maxLag ) {
2637         if( $maxLag ) {
2638                 $lb = wfGetLB();
2639                 list( $host, $lag ) = $lb->getMaxLag();
2640                 while( $lag > $maxLag ) {
2641                         $name = @gethostbyaddr( $host );
2642                         if( $name !== false ) {
2643                                 $host = $name;
2644                         }
2645                         print "Waiting for $host (lagged $lag seconds)...\n";
2646                         sleep($maxLag);
2647                         list( $host, $lag ) = $lb->getMaxLag();
2648                 }
2649         }
2650 }
2651
2652 /** Generate a random 32-character hexadecimal token.
2653  * @param mixed $salt Some sort of salt, if necessary, to add to random characters before hashing.
2654  */
2655 function wfGenerateToken( $salt = '' ) {
2656         $salt = serialize($salt);
2657
2658         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
2659 }