includes/GlobalFunctions.php

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