includes/GlobalFunctions.php

   1 <?php
   2
   3 if ( !defined( 'MEDIAWIKI' ) ) {
   4         die( "This file is part of MediaWiki, it is not a valid entry point" );
   5 }
   6
   7 /**
   8  * Global functions used everywhere
   9  */
  10
  11 require_once dirname(__FILE__) . '/LogPage.php';
  12 require_once dirname(__FILE__) . '/normal/UtfNormalUtil.php';
  13 require_once dirname(__FILE__) . '/XmlFunctions.php';
  14
  15 /**
  16  * Compatibility functions
  17  *
  18  * We more or less support PHP 5.0.x and up.
  19  * Re-implementations of newer functions or functions in non-standard
  20  * PHP extensions may be included here.
  21  */
  22 if( !function_exists('iconv') ) {
  23         # iconv support is not in the default configuration and so may not be present.
  24         # Assume will only ever use utf-8 and iso-8859-1.
  25         # This will *not* work in all circumstances.
  26         function iconv( $from, $to, $string ) {
  27                 if(strcasecmp( $from, $to ) == 0) return $string;
  28                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  29                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  30                 return $string;
  31         }
  32 }
  33
  34 # UTF-8 substr function based on a PHP manual comment
  35 if ( !function_exists( 'mb_substr' ) ) {
  36         function mb_substr( $str, $start ) {
  37                 $ar = array();
  38                 preg_match_all( '/./us', $str, $ar );
  39
  40                 if( func_num_args() >= 3 ) {
  41                         $end = func_get_arg( 2 );
  42                         return join( '', array_slice( $ar[0], $start, $end ) );
  43                 } else {
  44                         return join( '', array_slice( $ar[0], $start ) );
  45                 }
  46         }
  47 }
  48
  49 if ( !function_exists( 'mb_strlen' ) ) {
  50         /**
  51          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
  52          * @param string $str
  53          * @param string $enc optional encoding; ignored
  54          * @return int
  55          */
  56         function mb_strlen( $str, $enc="" ) {
  57                 $counts = count_chars( $str );
  58                 $total = 0;
  59
  60                 // Count ASCII bytes
  61                 for( $i = 0; $i < 0x80; $i++ ) {
  62                         $total += $counts[$i];
  63                 }
  64
  65                 // Count multibyte sequence heads
  66                 for( $i = 0xc0; $i < 0xff; $i++ ) {
  67                         $total += $counts[$i];
  68                 }
  69                 return $total;
  70         }
  71 }
  72
  73 if ( !function_exists( 'array_diff_key' ) ) {
  74         /**
  75          * Exists in PHP 5.1.0+
  76          * Not quite compatible, two-argument version only
  77          * Null values will cause problems due to this use of isset()
  78          */
  79         function array_diff_key( $left, $right ) {
  80                 $result = $left;
  81                 foreach ( $left as $key => $unused ) {
  82                         if ( isset( $right[$key] ) ) {
  83                                 unset( $result[$key] );
  84                         }
  85                 }
  86                 return $result;
  87         }
  88 }
  89
  90 /**
  91  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  92  */
  93 function wfArrayDiff2( $a, $b ) {
  94         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  95 }
  96 function wfArrayDiff2_cmp( $a, $b ) {
  97         if ( !is_array( $a ) ) {
  98                 return strcmp( $a, $b );
  99         } elseif ( count( $a ) !== count( $b ) ) {
 100                 return count( $a ) < count( $b ) ? -1 : 1;
 101         } else {
 102                 reset( $a );
 103                 reset( $b );
 104                 while( ( list( $keyA, $valueA ) = each( $a ) ) && ( list( $keyB, $valueB ) = each( $b ) ) ) {
 105                         $cmp = strcmp( $valueA, $valueB );
 106                         if ( $cmp !== 0 ) {
 107                                 return $cmp;
 108                         }
 109                 }
 110                 return 0;
 111         }
 112 }
 113
 114 /**
 115  * Wrapper for clone(), for compatibility with PHP4-friendly extensions.
 116  * PHP 5 won't let you declare a 'clone' function, even conditionally,
 117  * so it has to be a wrapper with a different name.
 118  */
 119 function wfClone( $object ) {
 120         return clone( $object );
 121 }
 122
 123 /**
 124  * Seed Mersenne Twister
 125  * No-op for compatibility; only necessary in PHP < 4.2.0
 126  */
 127 function wfSeedRandom() {
 128         /* No-op */
 129 }
 130
 131 /**
 132  * Get a random decimal value between 0 and 1, in a way
 133  * not likely to give duplicate values for any realistic
 134  * number of articles.
 135  *
 136  * @return string
 137  */
 138 function wfRandom() {
 139         # The maximum random value is "only" 2^31-1, so get two random
 140         # values to reduce the chance of dupes
 141         $max = mt_getrandmax() + 1;
 142         $rand = number_format( (mt_rand() * $max + mt_rand())
 143                 / $max / $max, 12, '.', '' );
 144         return $rand;
 145 }
 146
 147 /**
 148  * We want / and : to be included as literal characters in our title URLs.
 149  * %2F in the page titles seems to fatally break for some reason.
 150  *
 151  * @param $s String:
 152  * @return string
 153 */
 154 function wfUrlencode ( $s ) {
 155         $s = urlencode( $s );
 156         $s = preg_replace( '/%3[Aa]/', ':', $s );
 157         $s = preg_replace( '/%2[Ff]/', '/', $s );
 158
 159         return $s;
 160 }
 161
 162 /**
 163  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 164  * In normal operation this is a NOP.
 165  *
 166  * Controlling globals:
 167  * $wgDebugLogFile - points to the log file
 168  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 169  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 170  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 171  *
 172  * @param $text String
 173  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 174  */
 175 function wfDebug( $text, $logonly = false ) {
 176         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 177         static $recursion = 0;
 178
 179         static $cache = array(); // Cache of unoutputted messages
 180
 181         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 182         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 183                 return;
 184         }
 185
 186         if ( $wgDebugComments && !$logonly ) {
 187                 $cache[] = $text;
 188
 189                 if ( !isset( $wgOut ) ) {
 190                         return;
 191                 }
 192                 if ( !StubObject::isRealObject( $wgOut ) ) {
 193                         if ( $recursion ) {
 194                                 return;
 195                         }
 196                         $recursion++;
 197                         $wgOut->_unstub();
 198                         $recursion--;
 199                 }
 200
 201                 // add the message and possible cached ones to the output
 202                 array_map( array( $wgOut, 'debug' ), $cache );
 203                 $cache = array();
 204         }
 205         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 206                 # Strip unprintables; they can switch terminal modes when binary data
 207                 # gets dumped, which is pretty annoying.
 208                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 209                 wfErrorLog( $text, $wgDebugLogFile );
 210         }
 211 }
 212
 213 /**
 214  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 215  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 216  *
 217  * @param $logGroup String
 218  * @param $text String
 219  * @param $public Bool: whether to log the event in the public log if no private
 220  *                     log file is specified, (default true)
 221  */
 222 function wfDebugLog( $logGroup, $text, $public = true ) {
 223         global $wgDebugLogGroups;
 224         if( $text{strlen( $text ) - 1} != "\n" ) $text .= "\n";
 225         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 226                 $time = wfTimestamp( TS_DB );
 227                 $wiki = wfWikiID();
 228                 wfErrorLog( "$time $wiki: $text", $wgDebugLogGroups[$logGroup] );
 229         } else if ( $public === true ) {
 230                 wfDebug( $text, true );
 231         }
 232 }
 233
 234 /**
 235  * Log for database errors
 236  * @param $text String: database error message.
 237  */
 238 function wfLogDBError( $text ) {
 239         global $wgDBerrorLog, $wgDBname;
 240         if ( $wgDBerrorLog ) {
 241                 $host = trim(`hostname`);
 242                 $text = date('D M j G:i:s T Y') . "\t$host\t$wgDBname\t$text";
 243                 wfErrorLog( $text, $wgDBerrorLog );
 244         }
 245 }
 246
 247 /**
 248  * Log to a file without getting "file size exceeded" signals
 249  */
 250 function wfErrorLog( $text, $file ) {
 251         wfSuppressWarnings();
 252         $exists = file_exists( $file );
 253         $size = $exists ? filesize( $file ) : false;
 254         if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 255                 error_log( $text, 3, $file );
 256         }
 257         wfRestoreWarnings();
 258 }
 259
 260 /**
 261  * @todo document
 262  */
 263 function wfLogProfilingData() {
 264         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 265         global $wgProfiler, $wgUser;
 266         if ( !isset( $wgProfiler ) )
 267                 return;
 268
 269         $now = wfTime();
 270         $elapsed = $now - $wgRequestTime;
 271         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 272         $forward = '';
 273         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 274                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 275         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 276                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 277         if( !empty( $_SERVER['HTTP_FROM'] ) )
 278                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 279         if( $forward )
 280                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 281         // Don't unstub $wgUser at this late stage just for statistics purposes
 282         if( StubObject::isRealObject($wgUser) && $wgUser->isAnon() )
 283                 $forward .= ' anon';
 284         $log = sprintf( "%s\t%04.3f\t%s\n",
 285           gmdate( 'YmdHis' ), $elapsed,
 286           urldecode( $wgRequest->getRequestURL() . $forward ) );
 287         if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 288                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 289         }
 290 }
 291
 292 /**
 293  * Check if the wiki read-only lock file is present. This can be used to lock
 294  * off editing functions, but doesn't guarantee that the database will not be
 295  * modified.
 296  * @return bool
 297  */
 298 function wfReadOnly() {
 299         global $wgReadOnlyFile, $wgReadOnly;
 300
 301         if ( !is_null( $wgReadOnly ) ) {
 302                 return (bool)$wgReadOnly;
 303         }
 304         if ( '' == $wgReadOnlyFile ) {
 305                 return false;
 306         }
 307         // Set $wgReadOnly for faster access next time
 308         if ( is_file( $wgReadOnlyFile ) ) {
 309                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 310         } else {
 311                 $wgReadOnly = false;
 312         }
 313         return (bool)$wgReadOnly;
 314 }
 315
 316 function wfReadOnlyReason() {
 317         global $wgReadOnly;
 318         wfReadOnly();
 319         return $wgReadOnly;
 320 }
 321
 322 /**
 323  * Get a message from anywhere, for the current user language.
 324  *
 325  * Use wfMsgForContent() instead if the message should NOT
 326  * change depending on the user preferences.
 327  *
 328  * @param $key String: lookup key for the message, usually
 329  *    defined in languages/Language.php
 330  *
 331  * This function also takes extra optional parameters (not
 332  * shown in the function definition), which can by used to
 333  * insert variable text into the predefined message.
 334  */
 335 function wfMsg( $key ) {
 336         $args = func_get_args();
 337         array_shift( $args );
 338         return wfMsgReal( $key, $args, true );
 339 }
 340
 341 /**
 342  * Same as above except doesn't transform the message
 343  */
 344 function wfMsgNoTrans( $key ) {
 345         $args = func_get_args();
 346         array_shift( $args );
 347         return wfMsgReal( $key, $args, true, false, false );
 348 }
 349
 350 /**
 351  * Get a message from anywhere, for the current global language
 352  * set with $wgLanguageCode.
 353  *
 354  * Use this if the message should NOT change  dependent on the
 355  * language set in the user's preferences. This is the case for
 356  * most text written into logs, as well as link targets (such as
 357  * the name of the copyright policy page). Link titles, on the
 358  * other hand, should be shown in the UI language.
 359  *
 360  * Note that MediaWiki allows users to change the user interface
 361  * language in their preferences, but a single installation
 362  * typically only contains content in one language.
 363  *
 364  * Be wary of this distinction: If you use wfMsg() where you should
 365  * use wfMsgForContent(), a user of the software may have to
 366  * customize over 70 messages in order to, e.g., fix a link in every
 367  * possible language.
 368  *
 369  * @param $key String: lookup key for the message, usually
 370  *    defined in languages/Language.php
 371  */
 372 function wfMsgForContent( $key ) {
 373         global $wgForceUIMsgAsContentMsg;
 374         $args = func_get_args();
 375         array_shift( $args );
 376         $forcontent = true;
 377         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 378                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 379                 $forcontent = false;
 380         return wfMsgReal( $key, $args, true, $forcontent );
 381 }
 382
 383 /**
 384  * Same as above except doesn't transform the message
 385  */
 386 function wfMsgForContentNoTrans( $key ) {
 387         global $wgForceUIMsgAsContentMsg;
 388         $args = func_get_args();
 389         array_shift( $args );
 390         $forcontent = true;
 391         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 392                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 393                 $forcontent = false;
 394         return wfMsgReal( $key, $args, true, $forcontent, false );
 395 }
 396
 397 /**
 398  * Get a message from the language file, for the UI elements
 399  */
 400 function wfMsgNoDB( $key ) {
 401         $args = func_get_args();
 402         array_shift( $args );
 403         return wfMsgReal( $key, $args, false );
 404 }
 405
 406 /**
 407  * Get a message from the language file, for the content
 408  */
 409 function wfMsgNoDBForContent( $key ) {
 410         global $wgForceUIMsgAsContentMsg;
 411         $args = func_get_args();
 412         array_shift( $args );
 413         $forcontent = true;
 414         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 415                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 416                 $forcontent = false;
 417         return wfMsgReal( $key, $args, false, $forcontent );
 418 }
 419
 420
 421 /**
 422  * Really get a message
 423  * @param $key String: key to get.
 424  * @param $args
 425  * @param $useDB Boolean
 426  * @param $transform Boolean: Whether or not to transform the message.
 427  * @param $forContent Boolean
 428  * @return String: the requested message.
 429  */
 430 function wfMsgReal( $key, $args, $useDB = true, $forContent=false, $transform = true ) {
 431         wfProfileIn( __METHOD__ );
 432         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 433         $message = wfMsgReplaceArgs( $message, $args );
 434         wfProfileOut( __METHOD__ );
 435         return $message;
 436 }
 437
 438 /**
 439  * This function provides the message source for messages to be edited which are *not* stored in the database.
 440  * @param $key String:
 441  */
 442 function wfMsgWeirdKey ( $key ) {
 443         $source = wfMsgGetKey( $key, false, true, false );
 444         if ( wfEmptyMsg( $key, $source ) )
 445                 return "";
 446         else
 447                 return $source;
 448 }
 449
 450 /**
 451  * Fetch a message string value, but don't replace any keys yet.
 452  * @param string $key
 453  * @param bool $useDB
 454  * @param string $langcode Code of the language to get the message for, or
 455  *                         behaves as a content language switch if it is a
 456  *                         boolean.
 457  * @return string
 458  * @private
 459  */
 460 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 461         global $wgParser, $wgContLang, $wgMessageCache, $wgLang;
 462
 463         wfRunHooks('NormalizeMessageKey', array(&$key, &$useDB, &$langCode, &$transform));
 464
 465         # If $wgMessageCache isn't initialised yet, try to return something sensible.
 466         if( is_object( $wgMessageCache ) ) {
 467                 $message = $wgMessageCache->get( $key, $useDB, $langCode );
 468                 if ( $transform ) {
 469                         $message = $wgMessageCache->transform( $message );
 470                 }
 471         } else {
 472                 if( $langCode === true ) {
 473                         $lang = &$wgContLang;
 474                 } elseif( $langCode === false ) {
 475                         $lang = &$wgLang;
 476                 } else {
 477                         $validCodes = array_keys( Language::getLanguageNames() );
 478                         if( in_array( $langCode, $validCodes ) ) {
 479                                 # $langcode corresponds to a valid language.
 480                                 $lang = Language::factory( $langCode );
 481                         } else {
 482                                 # $langcode is a string, but not a valid language code; use content language.
 483                                 $lang =& $wgContLang;
 484                                 wfDebug( 'Invalid language code passed to wfMsgGetKey, falling back to content language.' );
 485                         }
 486                 }
 487
 488                 # MessageCache::get() does this already, Language::getMessage() doesn't
 489                 # ISSUE: Should we try to handle "message/lang" here too?
 490                 $key = str_replace( ' ' , '_' , $wgContLang->lcfirst( $key ) );
 491
 492                 if( is_object( $lang ) ) {
 493                         $message = $lang->getMessage( $key );
 494                 } else {
 495                         $message = false;
 496                 }
 497         }
 498
 499         return $message;
 500 }
 501
 502 /**
 503  * Replace message parameter keys on the given formatted output.
 504  *
 505  * @param string $message
 506  * @param array $args
 507  * @return string
 508  * @private
 509  */
 510 function wfMsgReplaceArgs( $message, $args ) {
 511         # Fix windows line-endings
 512         # Some messages are split with explode("\n", $msg)
 513         $message = str_replace( "\r", '', $message );
 514
 515         // Replace arguments
 516         if ( count( $args ) ) {
 517                 if ( is_array( $args[0] ) ) {
 518                         $args = array_values( $args[0] );
 519                 }
 520                 $replacementKeys = array();
 521                 foreach( $args as $n => $param ) {
 522                         $replacementKeys['$' . ($n + 1)] = $param;
 523                 }
 524                 $message = strtr( $message, $replacementKeys );
 525         }
 526
 527         return $message;
 528 }
 529
 530 /**
 531  * Return an HTML-escaped version of a message.
 532  * Parameter replacements, if any, are done *after* the HTML-escaping,
 533  * so parameters may contain HTML (eg links or form controls). Be sure
 534  * to pre-escape them if you really do want plaintext, or just wrap
 535  * the whole thing in htmlspecialchars().
 536  *
 537  * @param string $key
 538  * @param string ... parameters
 539  * @return string
 540  */
 541 function wfMsgHtml( $key ) {
 542         $args = func_get_args();
 543         array_shift( $args );
 544         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 545 }
 546
 547 /**
 548  * Return an HTML version of message
 549  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 550  * so parameters may contain HTML (eg links or form controls). Be sure
 551  * to pre-escape them if you really do want plaintext, or just wrap
 552  * the whole thing in htmlspecialchars().
 553  *
 554  * @param string $key
 555  * @param string ... parameters
 556  * @return string
 557  */
 558 function wfMsgWikiHtml( $key ) {
 559         global $wgOut;
 560         $args = func_get_args();
 561         array_shift( $args );
 562         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 563 }
 564
 565 /**
 566  * Returns message in the requested format
 567  * @param string $key Key of the message
 568  * @param array $options Processing rules:
 569  *  <i>parse</i>: parses wikitext to html
 570  *  <i>parseinline</i>: parses wikitext to html and removes the surrounding p's added by parser or tidy
 571  *  <i>escape</i>: filters message through htmlspecialchars
 572  *  <i>escapenoentities</i>: same, but allows entity references like &nbsp; through
 573  *  <i>replaceafter</i>: parameters are substituted after parsing or escaping
 574  *  <i>parsemag</i>: transform the message using magic phrases
 575  *  <i>content</i>: fetch message for content language instead of interface
 576  *  <i>language</i>: language code to fetch message for (overriden by <i>content</i>), its behaviour
 577  *                   with parser, parseinline and parsemag is undefined.
 578  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 579  */
 580 function wfMsgExt( $key, $options ) {
 581         global $wgOut, $wgParser;
 582
 583         $args = func_get_args();
 584         array_shift( $args );
 585         array_shift( $args );
 586
 587         if( !is_array($options) ) {
 588                 $options = array($options);
 589         }
 590
 591         if( in_array('content', $options) ) {
 592                 $forContent = true;
 593                 $langCode = true;
 594         } elseif( array_key_exists('language', $options) ) {
 595                 $forContent = false;
 596                 $langCode = $options['language'];
 597                 $validCodes = array_keys( Language::getLanguageNames() );
 598                 if( !in_array($options['language'], $validCodes) ) {
 599                         # Fallback to en, instead of whatever interface language we might have
 600                         $langCode = 'en';
 601                 }
 602         } else {
 603                 $forContent = false;
 604                 $langCode = false;
 605         }
 606
 607         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 608
 609         if( !in_array('replaceafter', $options) ) {
 610                 $string = wfMsgReplaceArgs( $string, $args );
 611         }
 612
 613         if( in_array('parse', $options) ) {
 614                 $string = $wgOut->parse( $string, true, !$forContent );
 615         } elseif ( in_array('parseinline', $options) ) {
 616                 $string = $wgOut->parse( $string, true, !$forContent );
 617                 $m = array();
 618                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 619                         $string = $m[1];
 620                 }
 621         } elseif ( in_array('parsemag', $options) ) {
 622                 global $wgMessageCache;
 623                 if ( isset( $wgMessageCache ) ) {
 624                         $string = $wgMessageCache->transform( $string, !$forContent );
 625                 }
 626         }
 627
 628         if ( in_array('escape', $options) ) {
 629                 $string = htmlspecialchars ( $string );
 630         } elseif ( in_array( 'escapenoentities', $options ) ) {
 631                 $string = htmlspecialchars( $string );
 632                 $string = str_replace( '&amp;', '&', $string );
 633                 $string = Sanitizer::normalizeCharReferences( $string );
 634         }
 635
 636         if( in_array('replaceafter', $options) ) {
 637                 $string = wfMsgReplaceArgs( $string, $args );
 638         }
 639
 640         return $string;
 641 }
 642
 643
 644 /**
 645  * Just like exit() but makes a note of it.
 646  * Commits open transactions except if the error parameter is set
 647  *
 648  * @deprecated Please return control to the caller or throw an exception
 649  */
 650 function wfAbruptExit( $error = false ){
 651         static $called = false;
 652         if ( $called ){
 653                 exit( -1 );
 654         }
 655         $called = true;
 656
 657         $bt = wfDebugBacktrace();
 658         if( $bt ) {
 659                 for($i = 0; $i < count($bt) ; $i++){
 660                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 661                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 662                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 663                 }
 664         } else {
 665                 wfDebug('WARNING: Abrupt exit\n');
 666         }
 667
 668         wfLogProfilingData();
 669
 670         if ( !$error ) {
 671                 wfGetLB()->closeAll();
 672         }
 673         exit( -1 );
 674 }
 675
 676 /**
 677  * @deprecated Please return control the caller or throw an exception
 678  */
 679 function wfErrorExit() {
 680         wfAbruptExit( true );
 681 }
 682
 683 /**
 684  * Print a simple message and die, returning nonzero to the shell if any.
 685  * Plain die() fails to return nonzero to the shell if you pass a string.
 686  * @param string $msg
 687  */
 688 function wfDie( $msg='' ) {
 689         echo $msg;
 690         die( 1 );
 691 }
 692
 693 /**
 694  * Throw a debugging exception. This function previously once exited the process,
 695  * but now throws an exception instead, with similar results.
 696  *
 697  * @param string $msg Message shown when dieing.
 698  */
 699 function wfDebugDieBacktrace( $msg = '' ) {
 700         throw new MWException( $msg );
 701 }
 702
 703 /**
 704  * Fetch server name for use in error reporting etc.
 705  * Use real server name if available, so we know which machine
 706  * in a server farm generated the current page.
 707  * @return string
 708  */
 709 function wfHostname() {
 710         if ( function_exists( 'posix_uname' ) ) {
 711                 // This function not present on Windows
 712                 $uname = @posix_uname();
 713         } else {
 714                 $uname = false;
 715         }
 716         if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 717                 return $uname['nodename'];
 718         } else {
 719                 # This may be a virtual server.
 720                 return $_SERVER['SERVER_NAME'];
 721         }
 722 }
 723
 724         /**
 725          * Returns a HTML comment with the elapsed time since request.
 726          * This method has no side effects.
 727          * @return string
 728          */
 729         function wfReportTime() {
 730                 global $wgRequestTime, $wgShowHostnames;
 731
 732                 $now = wfTime();
 733                 $elapsed = $now - $wgRequestTime;
 734
 735                 return $wgShowHostnames
 736                         ? sprintf( "<!-- Served by %s in %01.3f secs. -->", wfHostname(), $elapsed )
 737                         : sprintf( "<!-- Served in %01.3f secs. -->", $elapsed );
 738         }
 739
 740 /**
 741  * Safety wrapper for debug_backtrace().
 742  *
 743  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 744  * murky circumstances, which may be triggered in part by stub objects
 745  * or other fancy talkin'.
 746  *
 747  * Will return an empty array if Zend Optimizer is detected, otherwise
 748  * the output from debug_backtrace() (trimmed).
 749  *
 750  * @return array of backtrace information
 751  */
 752 function wfDebugBacktrace() {
 753         if( extension_loaded( 'Zend Optimizer' ) ) {
 754                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 755                 return array();
 756         } else {
 757                 return array_slice( debug_backtrace(), 1 );
 758         }
 759 }
 760
 761 function wfBacktrace() {
 762         global $wgCommandLineMode;
 763
 764         if ( $wgCommandLineMode ) {
 765                 $msg = '';
 766         } else {
 767                 $msg = "<ul>\n";
 768         }
 769         $backtrace = wfDebugBacktrace();
 770         foreach( $backtrace as $call ) {
 771                 if( isset( $call['file'] ) ) {
 772                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 773                         $file = $f[count($f)-1];
 774                 } else {
 775                         $file = '-';
 776                 }
 777                 if( isset( $call['line'] ) ) {
 778                         $line = $call['line'];
 779                 } else {
 780                         $line = '-';
 781                 }
 782                 if ( $wgCommandLineMode ) {
 783                         $msg .= "$file line $line calls ";
 784                 } else {
 785                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 786                 }
 787                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 788                 $msg .= $call['function'] . '()';
 789
 790                 if ( $wgCommandLineMode ) {
 791                         $msg .= "\n";
 792                 } else {
 793                         $msg .= "</li>\n";
 794                 }
 795         }
 796         if ( $wgCommandLineMode ) {
 797                 $msg .= "\n";
 798         } else {
 799                 $msg .= "</ul>\n";
 800         }
 801
 802         return $msg;
 803 }
 804
 805
 806 /* Some generic result counters, pulled out of SearchEngine */
 807
 808
 809 /**
 810  * @todo document
 811  */
 812 function wfShowingResults( $offset, $limit ) {
 813         global $wgLang;
 814         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 815 }
 816
 817 /**
 818  * @todo document
 819  */
 820 function wfShowingResultsNum( $offset, $limit, $num ) {
 821         global $wgLang;
 822         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 823 }
 824
 825 /**
 826  * @todo document
 827  */
 828 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 829         global $wgLang;
 830         $fmtLimit = $wgLang->formatNum( $limit );
 831         $prev = wfMsg( 'prevn', $fmtLimit );
 832         $next = wfMsg( 'nextn', $fmtLimit );
 833
 834         if( is_object( $link ) ) {
 835                 $title =& $link;
 836         } else {
 837                 $title = Title::newFromText( $link );
 838                 if( is_null( $title ) ) {
 839                         return false;
 840                 }
 841         }
 842
 843         if ( 0 != $offset ) {
 844                 $po = $offset - $limit;
 845                 if ( $po < 0 ) { $po = 0; }
 846                 $q = "limit={$limit}&offset={$po}";
 847                 if ( '' != $query ) { $q .= '&'.$query; }
 848                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
 849         } else { $plink = $prev; }
 850
 851         $no = $offset + $limit;
 852         $q = 'limit='.$limit.'&offset='.$no;
 853         if ( '' != $query ) { $q .= '&'.$query; }
 854
 855         if ( $atend ) {
 856                 $nlink = $next;
 857         } else {
 858                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
 859         }
 860         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 861           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 862           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 863           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 864           wfNumLink( $offset, 500, $title, $query );
 865
 866         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 867 }
 868
 869 /**
 870  * @todo document
 871  */
 872 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 873         global $wgLang;
 874         if ( '' == $query ) { $q = ''; }
 875         else { $q = $query.'&'; }
 876         $q .= 'limit='.$limit.'&offset='.$offset;
 877
 878         $fmtLimit = $wgLang->formatNum( $limit );
 879         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-numlink\">{$fmtLimit}</a>";
 880         return $s;
 881 }
 882
 883 /**
 884  * @todo document
 885  * @todo FIXME: we may want to blacklist some broken browsers
 886  *
 887  * @return bool Whereas client accept gzip compression
 888  */
 889 function wfClientAcceptsGzip() {
 890         global $wgUseGzip;
 891         if( $wgUseGzip ) {
 892                 # FIXME: we may want to blacklist some broken browsers
 893                 $m = array();
 894                 if( preg_match(
 895                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 896                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 897                         $m ) ) {
 898                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 899                         wfDebug( " accepts gzip\n" );
 900                         return true;
 901                 }
 902         }
 903         return false;
 904 }
 905
 906 /**
 907  * Obtain the offset and limit values from the request string;
 908  * used in special pages
 909  *
 910  * @param $deflimit Default limit if none supplied
 911  * @param $optionname Name of a user preference to check against
 912  * @return array
 913  *
 914  */
 915 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 916         global $wgRequest;
 917         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 918 }
 919
 920 /**
 921  * Escapes the given text so that it may be output using addWikiText()
 922  * without any linking, formatting, etc. making its way through. This
 923  * is achieved by substituting certain characters with HTML entities.
 924  * As required by the callers, <nowiki> is not used. It currently does
 925  * not filter out characters which have special meaning only at the
 926  * start of a line, such as "*".
 927  *
 928  * @param string $text Text to be escaped
 929  */
 930 function wfEscapeWikiText( $text ) {
 931         $text = str_replace(
 932                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
 933                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
 934                 htmlspecialchars($text) );
 935         return $text;
 936 }
 937
 938 /**
 939  * @todo document
 940  */
 941 function wfQuotedPrintable( $string, $charset = '' ) {
 942         # Probably incomplete; see RFC 2045
 943         if( empty( $charset ) ) {
 944                 global $wgInputEncoding;
 945                 $charset = $wgInputEncoding;
 946         }
 947         $charset = strtoupper( $charset );
 948         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 949
 950         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 951         $replace = $illegal . '\t ?_';
 952         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 953         $out = "=?$charset?Q?";
 954         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 955         $out .= '?=';
 956         return $out;
 957 }
 958
 959
 960 /**
 961  * @todo document
 962  * @return float
 963  */
 964 function wfTime() {
 965         return microtime(true);
 966 }
 967
 968 /**
 969  * Sets dest to source and returns the original value of dest
 970  * If source is NULL, it just returns the value, it doesn't set the variable
 971  */
 972 function wfSetVar( &$dest, $source ) {
 973         $temp = $dest;
 974         if ( !is_null( $source ) ) {
 975                 $dest = $source;
 976         }
 977         return $temp;
 978 }
 979
 980 /**
 981  * As for wfSetVar except setting a bit
 982  */
 983 function wfSetBit( &$dest, $bit, $state = true ) {
 984         $temp = (bool)($dest & $bit );
 985         if ( !is_null( $state ) ) {
 986                 if ( $state ) {
 987                         $dest |= $bit;
 988                 } else {
 989                         $dest &= ~$bit;
 990                 }
 991         }
 992         return $temp;
 993 }
 994
 995 /**
 996  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 997  * "days=7&limit=100". Options in the first array override options in the second.
 998  * Options set to "" will not be output.
 999  */
1000 function wfArrayToCGI( $array1, $array2 = NULL )
1001 {
1002         if ( !is_null( $array2 ) ) {
1003                 $array1 = $array1 + $array2;
1004         }
1005
1006         $cgi = '';
1007         foreach ( $array1 as $key => $value ) {
1008                 if ( '' !== $value ) {
1009                         if ( '' != $cgi ) {
1010                                 $cgi .= '&';
1011                         }
1012                         if(is_array($value))
1013                         {
1014                                 $firstTime = true;
1015                                 foreach($value as $v)
1016                                 {
1017                                         $cgi .= ($firstTime ? '' : '&') .
1018                                                 urlencode( $key . '[]' ) . '=' .
1019                                                 urlencode( $v );
1020                                         $firstTime = false;
1021                                 }
1022                         }
1023                         else
1024                                 $cgi .= urlencode( $key ) . '=' .
1025                                         urlencode( $value );
1026                 }
1027         }
1028         return $cgi;
1029 }
1030
1031 /**
1032  * Append a query string to an existing URL, which may or may not already
1033  * have query string parameters already. If so, they will be combined.
1034  *
1035  * @param string $url
1036  * @param string $query
1037  * @return string
1038  */
1039 function wfAppendQuery( $url, $query ) {
1040         if( $query != '' ) {
1041                 if( false === strpos( $url, '?' ) ) {
1042                         $url .= '?';
1043                 } else {
1044                         $url .= '&';
1045                 }
1046                 $url .= $query;
1047         }
1048         return $url;
1049 }
1050
1051 /**
1052  * Expand a potentially local URL to a fully-qualified URL.
1053  * Assumes $wgServer is correct. :)
1054  * @param string $url, either fully-qualified or a local path + query
1055  * @return string Fully-qualified URL
1056  */
1057 function wfExpandUrl( $url ) {
1058         if( substr( $url, 0, 1 ) == '/' ) {
1059                 global $wgServer;
1060                 return $wgServer . $url;
1061         } else {
1062                 return $url;
1063         }
1064 }
1065
1066 /**
1067  * This is obsolete, use SquidUpdate::purge()
1068  * @deprecated
1069  */
1070 function wfPurgeSquidServers ($urlArr) {
1071         SquidUpdate::purge( $urlArr );
1072 }
1073
1074 /**
1075  * Windows-compatible version of escapeshellarg()
1076  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1077  * function puts single quotes in regardless of OS
1078  */
1079 function wfEscapeShellArg( ) {
1080         $args = func_get_args();
1081         $first = true;
1082         $retVal = '';
1083         foreach ( $args as $arg ) {
1084                 if ( !$first ) {
1085                         $retVal .= ' ';
1086                 } else {
1087                         $first = false;
1088                 }
1089
1090                 if ( wfIsWindows() ) {
1091                         // Escaping for an MSVC-style command line parser
1092                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1093                         // Double the backslashes before any double quotes. Escape the double quotes.
1094                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1095                         $arg = '';
1096                         $delim = false;
1097                         foreach ( $tokens as $token ) {
1098                                 if ( $delim ) {
1099                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1100                                 } else {
1101                                         $arg .= $token;
1102                                 }
1103                                 $delim = !$delim;
1104                         }
1105                         // Double the backslashes before the end of the string, because
1106                         // we will soon add a quote
1107                         $m = array();
1108                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1109                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1110                         }
1111
1112                         // Add surrounding quotes
1113                         $retVal .= '"' . $arg . '"';
1114                 } else {
1115                         $retVal .= escapeshellarg( $arg );
1116                 }
1117         }
1118         return $retVal;
1119 }
1120
1121 /**
1122  * wfMerge attempts to merge differences between three texts.
1123  * Returns true for a clean merge and false for failure or a conflict.
1124  */
1125 function wfMerge( $old, $mine, $yours, &$result ){
1126         global $wgDiff3;
1127
1128         # This check may also protect against code injection in
1129         # case of broken installations.
1130         if(! file_exists( $wgDiff3 ) ){
1131                 wfDebug( "diff3 not found\n" );
1132                 return false;
1133         }
1134
1135         # Make temporary files
1136         $td = wfTempDir();
1137         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1138         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1139         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1140
1141         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1142         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1143         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1144
1145         # Check for a conflict
1146         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1147           wfEscapeShellArg( $mytextName ) . ' ' .
1148           wfEscapeShellArg( $oldtextName ) . ' ' .
1149           wfEscapeShellArg( $yourtextName );
1150         $handle = popen( $cmd, 'r' );
1151
1152         if( fgets( $handle, 1024 ) ){
1153                 $conflict = true;
1154         } else {
1155                 $conflict = false;
1156         }
1157         pclose( $handle );
1158
1159         # Merge differences
1160         $cmd = $wgDiff3 . ' -a -e --merge ' .
1161           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1162         $handle = popen( $cmd, 'r' );
1163         $result = '';
1164         do {
1165                 $data = fread( $handle, 8192 );
1166                 if ( strlen( $data ) == 0 ) {
1167                         break;
1168                 }
1169                 $result .= $data;
1170         } while ( true );
1171         pclose( $handle );
1172         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1173
1174         if ( $result === '' && $old !== '' && $conflict == false ) {
1175                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1176                 $conflict = true;
1177         }
1178         return ! $conflict;
1179 }
1180
1181 /**
1182  * Returns unified plain-text diff of two texts.
1183  * Useful for machine processing of diffs.
1184  * @param $before string The text before the changes.
1185  * @param $after string The text after the changes.
1186  * @param $params string Command-line options for the diff command.
1187  * @return string Unified diff of $before and $after
1188  */
1189 function wfDiff( $before, $after, $params = '-u' ) {
1190         global $wgDiff;
1191
1192         # This check may also protect against code injection in
1193         # case of broken installations.
1194         if( !file_exists( $wgDiff ) ){
1195                 wfDebug( "diff executable not found\n" );
1196                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1197                 $format = new UnifiedDiffFormatter();
1198                 return $format->format( $diffs );
1199         }
1200
1201         # Make temporary files
1202         $td = wfTempDir();
1203         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1204         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1205
1206         fwrite( $oldtextFile, $before ); fclose( $oldtextFile );
1207         fwrite( $newtextFile, $after ); fclose( $newtextFile );
1208
1209         // Get the diff of the two files
1210         $cmd = "$wgDiff " . $params . ' ' .wfEscapeShellArg( $oldtextName, $newtextName );
1211
1212         $h = popen( $cmd, 'r' );
1213
1214         $diff = '';
1215
1216         do {
1217                 $data = fread( $h, 8192 );
1218                 if ( strlen( $data ) == 0 ) {
1219                         break;
1220                 }
1221                 $diff .= $data;
1222         } while ( true );
1223
1224         // Clean up
1225         pclose( $h );
1226         unlink( $oldtextName );
1227         unlink( $newtextName );
1228
1229         // Kill the --- and +++ lines. They're not useful.
1230         $diff_lines = explode( "\n", $diff );
1231         if (strpos( $diff_lines[0], '---' ) === 0) {
1232                 unset($diff_lines[0]);
1233         }
1234         if (strpos( $diff_lines[1], '+++' ) === 0) {
1235                 unset($diff_lines[1]);
1236         }
1237
1238         $diff = implode( "\n", $diff_lines );
1239
1240         return $diff;
1241 }
1242
1243 /**
1244  * @todo document
1245  */
1246 function wfVarDump( $var ) {
1247         global $wgOut;
1248         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1249         if ( headers_sent() || !@is_object( $wgOut ) ) {
1250                 print $s;
1251         } else {
1252                 $wgOut->addHTML( $s );
1253         }
1254 }
1255
1256 /**
1257  * Provide a simple HTTP error.
1258  */
1259 function wfHttpError( $code, $label, $desc ) {
1260         global $wgOut;
1261         $wgOut->disable();
1262         header( "HTTP/1.0 $code $label" );
1263         header( "Status: $code $label" );
1264         $wgOut->sendCacheControl();
1265
1266         header( 'Content-type: text/html; charset=utf-8' );
1267         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1268                 "<html><head><title>" .
1269                 htmlspecialchars( $label ) .
1270                 "</title></head><body><h1>" .
1271                 htmlspecialchars( $label ) .
1272                 "</h1><p>" .
1273                 nl2br( htmlspecialchars( $desc ) ) .
1274                 "</p></body></html>\n";
1275 }
1276
1277 /**
1278  * Clear away any user-level output buffers, discarding contents.
1279  *
1280  * Suitable for 'starting afresh', for instance when streaming
1281  * relatively large amounts of data without buffering, or wanting to
1282  * output image files without ob_gzhandler's compression.
1283  *
1284  * The optional $resetGzipEncoding parameter controls suppression of
1285  * the Content-Encoding header sent by ob_gzhandler; by default it
1286  * is left. See comments for wfClearOutputBuffers() for why it would
1287  * be used.
1288  *
1289  * Note that some PHP configuration options may add output buffer
1290  * layers which cannot be removed; these are left in place.
1291  *
1292  * @param bool $resetGzipEncoding
1293  */
1294 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1295         if( $resetGzipEncoding ) {
1296                 // Suppress Content-Encoding and Content-Length
1297                 // headers from 1.10+s wfOutputHandler
1298                 global $wgDisableOutputCompression;
1299                 $wgDisableOutputCompression = true;
1300         }
1301         while( $status = ob_get_status() ) {
1302                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1303                         // Probably from zlib.output_compression or other
1304                         // PHP-internal setting which can't be removed.
1305                         //
1306                         // Give up, and hope the result doesn't break
1307                         // output behavior.
1308                         break;
1309                 }
1310                 if( !ob_end_clean() ) {
1311                         // Could not remove output buffer handler; abort now
1312                         // to avoid getting in some kind of infinite loop.
1313                         break;
1314                 }
1315                 if( $resetGzipEncoding ) {
1316                         if( $status['name'] == 'ob_gzhandler' ) {
1317                                 // Reset the 'Content-Encoding' field set by this handler
1318                                 // so we can start fresh.
1319                                 header( 'Content-Encoding:' );
1320                         }
1321                 }
1322         }
1323 }
1324
1325 /**
1326  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1327  *
1328  * Clear away output buffers, but keep the Content-Encoding header
1329  * produced by ob_gzhandler, if any.
1330  *
1331  * This should be used for HTTP 304 responses, where you need to
1332  * preserve the Content-Encoding header of the real result, but
1333  * also need to suppress the output of ob_gzhandler to keep to spec
1334  * and avoid breaking Firefox in rare cases where the headers and
1335  * body are broken over two packets.
1336  */
1337 function wfClearOutputBuffers() {
1338         wfResetOutputBuffers( false );
1339 }
1340
1341 /**
1342  * Converts an Accept-* header into an array mapping string values to quality
1343  * factors
1344  */
1345 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1346         # No arg means accept anything (per HTTP spec)
1347         if( !$accept ) {
1348                 return array( $def => 1.0 );
1349         }
1350
1351         $prefs = array();
1352
1353         $parts = explode( ',', $accept );
1354
1355         foreach( $parts as $part ) {
1356                 # FIXME: doesn't deal with params like 'text/html; level=1'
1357                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1358                 $match = array();
1359                 if( !isset( $qpart ) ) {
1360                         $prefs[$value] = 1.0;
1361                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1362                         $prefs[$value] = floatval($match[1]);
1363                 }
1364         }
1365
1366         return $prefs;
1367 }
1368
1369 /**
1370  * Checks if a given MIME type matches any of the keys in the given
1371  * array. Basic wildcards are accepted in the array keys.
1372  *
1373  * Returns the matching MIME type (or wildcard) if a match, otherwise
1374  * NULL if no match.
1375  *
1376  * @param string $type
1377  * @param array $avail
1378  * @return string
1379  * @private
1380  */
1381 function mimeTypeMatch( $type, $avail ) {
1382         if( array_key_exists($type, $avail) ) {
1383                 return $type;
1384         } else {
1385                 $parts = explode( '/', $type );
1386                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1387                         return $parts[0] . '/*';
1388                 } elseif( array_key_exists( '*/*', $avail ) ) {
1389                         return '*/*';
1390                 } else {
1391                         return NULL;
1392                 }
1393         }
1394 }
1395
1396 /**
1397  * Returns the 'best' match between a client's requested internet media types
1398  * and the server's list of available types. Each list should be an associative
1399  * array of type to preference (preference is a float between 0.0 and 1.0).
1400  * Wildcards in the types are acceptable.
1401  *
1402  * @param array $cprefs Client's acceptable type list
1403  * @param array $sprefs Server's offered types
1404  * @return string
1405  *
1406  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1407  * XXX: generalize to negotiate other stuff
1408  */
1409 function wfNegotiateType( $cprefs, $sprefs ) {
1410         $combine = array();
1411
1412         foreach( array_keys($sprefs) as $type ) {
1413                 $parts = explode( '/', $type );
1414                 if( $parts[1] != '*' ) {
1415                         $ckey = mimeTypeMatch( $type, $cprefs );
1416                         if( $ckey ) {
1417                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1418                         }
1419                 }
1420         }
1421
1422         foreach( array_keys( $cprefs ) as $type ) {
1423                 $parts = explode( '/', $type );
1424                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1425                         $skey = mimeTypeMatch( $type, $sprefs );
1426                         if( $skey ) {
1427                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1428                         }
1429                 }
1430         }
1431
1432         $bestq = 0;
1433         $besttype = NULL;
1434
1435         foreach( array_keys( $combine ) as $type ) {
1436                 if( $combine[$type] > $bestq ) {
1437                         $besttype = $type;
1438                         $bestq = $combine[$type];
1439                 }
1440         }
1441
1442         return $besttype;
1443 }
1444
1445 /**
1446  * Array lookup
1447  * Returns an array where the values in the first array are replaced by the
1448  * values in the second array with the corresponding keys
1449  *
1450  * @return array
1451  */
1452 function wfArrayLookup( $a, $b ) {
1453         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1454 }
1455
1456 /**
1457  * Convenience function; returns MediaWiki timestamp for the present time.
1458  * @return string
1459  */
1460 function wfTimestampNow() {
1461         # return NOW
1462         return wfTimestamp( TS_MW, time() );
1463 }
1464
1465 /**
1466  * Reference-counted warning suppression
1467  */
1468 function wfSuppressWarnings( $end = false ) {
1469         static $suppressCount = 0;
1470         static $originalLevel = false;
1471
1472         if ( $end ) {
1473                 if ( $suppressCount ) {
1474                         --$suppressCount;
1475                         if ( !$suppressCount ) {
1476                                 error_reporting( $originalLevel );
1477                         }
1478                 }
1479         } else {
1480                 if ( !$suppressCount ) {
1481                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1482                 }
1483                 ++$suppressCount;
1484         }
1485 }
1486
1487 /**
1488  * Restore error level to previous value
1489  */
1490 function wfRestoreWarnings() {
1491         wfSuppressWarnings( true );
1492 }
1493
1494 # Autodetect, convert and provide timestamps of various types
1495
1496 /**
1497  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1498  */
1499 define('TS_UNIX', 0);
1500
1501 /**
1502  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1503  */
1504 define('TS_MW', 1);
1505
1506 /**
1507  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1508  */
1509 define('TS_DB', 2);
1510
1511 /**
1512  * RFC 2822 format, for E-mail and HTTP headers
1513  */
1514 define('TS_RFC2822', 3);
1515
1516 /**
1517  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1518  *
1519  * This is used by Special:Export
1520  */
1521 define('TS_ISO_8601', 4);
1522
1523 /**
1524  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1525  *
1526  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1527  *       DateTime tag and page 36 for the DateTimeOriginal and
1528  *       DateTimeDigitized tags.
1529  */
1530 define('TS_EXIF', 5);
1531
1532 /**
1533  * Oracle format time.
1534  */
1535 define('TS_ORACLE', 6);
1536
1537 /**
1538  * Postgres format time.
1539  */
1540 define('TS_POSTGRES', 7);
1541
1542 /**
1543  * @param mixed $outputtype A timestamp in one of the supported formats, the
1544  *                          function will autodetect which format is supplied
1545  *                          and act accordingly.
1546  * @return string Time in the format specified in $outputtype
1547  */
1548 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1549         $uts = 0;
1550         $da = array();
1551         if ($ts==0) {
1552                 $uts=time();
1553         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1554                 # TS_DB
1555         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1556                 # TS_EXIF
1557         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1558                 # TS_MW
1559         } elseif (preg_match('/^\d{1,13}$/D',$ts)) {
1560                 # TS_UNIX
1561                 $uts = $ts;
1562         } elseif (preg_match('/^\d{1,2}-...-\d\d(?:\d\d)? \d\d\.\d\d\.\d\d/', $ts)) {
1563                 # TS_ORACLE
1564                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1565                                 str_replace("+00:00", "UTC", $ts)));
1566         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1567                 # TS_ISO_8601
1568         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1569                 # TS_POSTGRES
1570         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1571                 # TS_POSTGRES
1572         } else {
1573                 # Bogus value; fall back to the epoch...
1574                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1575                 $uts = 0;
1576         }
1577
1578         if (count( $da ) ) {
1579                 // Warning! gmmktime() acts oddly if the month or day is set to 0
1580                 // We may want to handle that explicitly at some point
1581                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1582                         (int)$da[2],(int)$da[3],(int)$da[1]);
1583         }
1584
1585         switch($outputtype) {
1586                 case TS_UNIX:
1587                         return $uts;
1588                 case TS_MW:
1589                         return gmdate( 'YmdHis', $uts );
1590                 case TS_DB:
1591                         return gmdate( 'Y-m-d H:i:s', $uts );
1592                 case TS_ISO_8601:
1593                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1594                 // This shouldn't ever be used, but is included for completeness
1595                 case TS_EXIF:
1596                         return gmdate(  'Y:m:d H:i:s', $uts );
1597                 case TS_RFC2822:
1598                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1599                 case TS_ORACLE:
1600                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1601                 case TS_POSTGRES:
1602                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1603                 default:
1604                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1605         }
1606 }
1607
1608 /**
1609  * Return a formatted timestamp, or null if input is null.
1610  * For dealing with nullable timestamp columns in the database.
1611  * @param int $outputtype
1612  * @param string $ts
1613  * @return string
1614  */
1615 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1616         if( is_null( $ts ) ) {
1617                 return null;
1618         } else {
1619                 return wfTimestamp( $outputtype, $ts );
1620         }
1621 }
1622
1623 /**
1624  * Check if the operating system is Windows
1625  *
1626  * @return bool True if it's Windows, False otherwise.
1627  */
1628 function wfIsWindows() {
1629         if (substr(php_uname(), 0, 7) == 'Windows') {
1630                 return true;
1631         } else {
1632                 return false;
1633         }
1634 }
1635
1636 /**
1637  * Swap two variables
1638  */
1639 function swap( &$x, &$y ) {
1640         $z = $x;
1641         $x = $y;
1642         $y = $z;
1643 }
1644
1645 function wfGetCachedNotice( $name ) {
1646         global $wgOut, $parserMemc;
1647         $fname = 'wfGetCachedNotice';
1648         wfProfileIn( $fname );
1649
1650         $needParse = false;
1651
1652         if( $name === 'default' ) {
1653                 // special case
1654                 global $wgSiteNotice;
1655                 $notice = $wgSiteNotice;
1656                 if( empty( $notice ) ) {
1657                         wfProfileOut( $fname );
1658                         return false;
1659                 }
1660         } else {
1661                 $notice = wfMsgForContentNoTrans( $name );
1662                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1663                         wfProfileOut( $fname );
1664                         return( false );
1665                 }
1666         }
1667
1668         $cachedNotice = $parserMemc->get( wfMemcKey( $name ) );
1669         if( is_array( $cachedNotice ) ) {
1670                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1671                         $notice = $cachedNotice['html'];
1672                 } else {
1673                         $needParse = true;
1674                 }
1675         } else {
1676                 $needParse = true;
1677         }
1678
1679         if( $needParse ) {
1680                 if( is_object( $wgOut ) ) {
1681                         $parsed = $wgOut->parse( $notice );
1682                         $parserMemc->set( wfMemcKey( $name ), array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1683                         $notice = $parsed;
1684                 } else {
1685                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1686                         $notice = '';
1687                 }
1688         }
1689
1690         wfProfileOut( $fname );
1691         return $notice;
1692 }
1693
1694 function wfGetNamespaceNotice() {
1695         global $wgTitle;
1696
1697         # Paranoia
1698         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1699                 return "";
1700
1701         $fname = 'wfGetNamespaceNotice';
1702         wfProfileIn( $fname );
1703
1704         $key = "namespacenotice-" . $wgTitle->getNsText();
1705         $namespaceNotice = wfGetCachedNotice( $key );
1706         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1707                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1708         } else {
1709                 $namespaceNotice = "";
1710         }
1711
1712         wfProfileOut( $fname );
1713         return $namespaceNotice;
1714 }
1715
1716 function wfGetSiteNotice() {
1717         global $wgUser, $wgSiteNotice;
1718         $fname = 'wfGetSiteNotice';
1719         wfProfileIn( $fname );
1720         $siteNotice = '';
1721
1722         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1723                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1724                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1725                 } else {
1726                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1727                         if( !$anonNotice ) {
1728                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1729                         } else {
1730                                 $siteNotice = $anonNotice;
1731                         }
1732                 }
1733                 if( !$siteNotice ) {
1734                         $siteNotice = wfGetCachedNotice( 'default' );
1735                 }
1736         }
1737
1738         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1739         wfProfileOut( $fname );
1740         return $siteNotice;
1741 }
1742
1743 /**
1744  * BC wrapper for MimeMagic::singleton()
1745  * @deprecated
1746  */
1747 function &wfGetMimeMagic() {
1748         return MimeMagic::singleton();
1749 }
1750
1751 /**
1752  * Tries to get the system directory for temporary files.
1753  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1754  * and if none are set /tmp is returned as the generic Unix default.
1755  *
1756  * NOTE: When possible, use the tempfile() function to create temporary
1757  * files to avoid race conditions on file creation, etc.
1758  *
1759  * @return string
1760  */
1761 function wfTempDir() {
1762         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1763                 $tmp = getenv( $var );
1764                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1765                         return $tmp;
1766                 }
1767         }
1768         # Hope this is Unix of some kind!
1769         return '/tmp';
1770 }
1771
1772 /**
1773  * Make directory, and make all parent directories if they don't exist
1774  *
1775  * @param string $fullDir Full path to directory to create
1776  * @param int $mode Chmod value to use, default is $wgDirectoryMode
1777  * @return bool
1778  */
1779 function wfMkdirParents( $fullDir, $mode = null ) {
1780         global $wgDirectoryMode;
1781         if( strval( $fullDir ) === '' )
1782                 return true;
1783         if( file_exists( $fullDir ) )
1784                 return true;
1785         // If not defined or isn't an int, set to default
1786         if ( is_null( $mode ) ) {
1787                 $mode = $wgDirectoryMode;
1788         }
1789
1790
1791         # Go back through the paths to find the first directory that exists
1792         $currentDir = $fullDir;
1793         $createList = array();
1794         while ( strval( $currentDir ) !== '' && !file_exists( $currentDir ) ) {
1795                 # Strip trailing slashes
1796                 $currentDir = rtrim( $currentDir, '/\\' );
1797
1798                 # Add to create list
1799                 $createList[] = $currentDir;
1800
1801                 # Find next delimiter searching from the end
1802                 $p = max( strrpos( $currentDir, '/' ), strrpos( $currentDir, '\\' ) );
1803                 if ( $p === false ) {
1804                         $currentDir = false;
1805                 } else {
1806                         $currentDir = substr( $currentDir, 0, $p );
1807                 }
1808         }
1809
1810         if ( count( $createList ) == 0 ) {
1811                 # Directory specified already exists
1812                 return true;
1813         } elseif ( $currentDir === false ) {
1814                 # Went all the way back to root and it apparently doesn't exist
1815                 wfDebugLog( 'mkdir', "Root doesn't exist?\n" );
1816                 return false;
1817         }
1818         # Now go forward creating directories
1819         $createList = array_reverse( $createList );
1820
1821         # Is the parent directory writable?
1822         if ( $currentDir === '' ) {
1823                 $currentDir = '/';
1824         }
1825         if ( !is_writable( $currentDir ) ) {
1826                 wfDebugLog( 'mkdir', "Not writable: $currentDir\n" );
1827                 return false;
1828         }
1829
1830         foreach ( $createList as $dir ) {
1831                 # use chmod to override the umask, as suggested by the PHP manual
1832                 if ( !mkdir( $dir, $mode ) || !chmod( $dir, $mode ) ) {
1833                         wfDebugLog( 'mkdir', "Unable to create directory $dir\n" );
1834                         return false;
1835                 }
1836         }
1837         return true;
1838 }
1839
1840 /**
1841  * Increment a statistics counter
1842  */
1843 function wfIncrStats( $key ) {
1844         global $wgStatsMethod;
1845
1846         if( $wgStatsMethod == 'udp' ) {
1847                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
1848                 static $socket;
1849                 if (!$socket) {
1850                         $socket=socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
1851                         $statline="stats/{$wgDBname} - 1 1 1 1 1 -total\n";
1852                         socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1853                 }
1854                 $statline="stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
1855                 @socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1856         } elseif( $wgStatsMethod == 'cache' ) {
1857                 global $wgMemc;
1858                 $key = wfMemcKey( 'stats', $key );
1859                 if ( is_null( $wgMemc->incr( $key ) ) ) {
1860                         $wgMemc->add( $key, 1 );
1861                 }
1862         } else {
1863                 // Disabled
1864         }
1865 }
1866
1867 /**
1868  * @param mixed $nr The number to format
1869  * @param int $acc The number of digits after the decimal point, default 2
1870  * @param bool $round Whether or not to round the value, default true
1871  * @return float
1872  */
1873 function wfPercent( $nr, $acc = 2, $round = true ) {
1874         $ret = sprintf( "%.${acc}f", $nr );
1875         return $round ? round( $ret, $acc ) . '%' : "$ret%";
1876 }
1877
1878 /**
1879  * Encrypt a username/password.
1880  *
1881  * @param string $userid ID of the user
1882  * @param string $password Password of the user
1883  * @return string Hashed password
1884  * @deprecated Use User::crypt() or User::oldCrypt() instead
1885  */
1886 function wfEncryptPassword( $userid, $password ) {
1887         wfDeprecated(__FUNCTION__);
1888         # Just wrap around User::oldCrypt()
1889         return User::oldCrypt($password, $userid);
1890 }
1891
1892 /**
1893  * Appends to second array if $value differs from that in $default
1894  */
1895 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
1896         if ( is_null( $changed ) ) {
1897                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
1898         }
1899         if ( $default[$key] !== $value ) {
1900                 $changed[$key] = $value;
1901         }
1902 }
1903
1904 /**
1905  * Since wfMsg() and co suck, they don't return false if the message key they
1906  * looked up didn't exist but a XHTML string, this function checks for the
1907  * nonexistance of messages by looking at wfMsg() output
1908  *
1909  * @param $msg      The message key looked up
1910  * @param $wfMsgOut The output of wfMsg*()
1911  * @return bool
1912  */
1913 function wfEmptyMsg( $msg, $wfMsgOut ) {
1914         return $wfMsgOut === htmlspecialchars( "<$msg>" );
1915 }
1916
1917 /**
1918  * Find out whether or not a mixed variable exists in a string
1919  *
1920  * @param mixed  needle
1921  * @param string haystack
1922  * @return bool
1923  */
1924 function in_string( $needle, $str ) {
1925         return strpos( $str, $needle ) !== false;
1926 }
1927
1928 function wfSpecialList( $page, $details ) {
1929         global $wgContLang;
1930         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
1931         return $page . $details;
1932 }
1933
1934 /**
1935  * Returns a regular expression of url protocols
1936  *
1937  * @return string
1938  */
1939 function wfUrlProtocols() {
1940         global $wgUrlProtocols;
1941
1942         // Support old-style $wgUrlProtocols strings, for backwards compatibility
1943         // with LocalSettings files from 1.5
1944         if ( is_array( $wgUrlProtocols ) ) {
1945                 $protocols = array();
1946                 foreach ($wgUrlProtocols as $protocol)
1947                         $protocols[] = preg_quote( $protocol, '/' );
1948
1949                 return implode( '|', $protocols );
1950         } else {
1951                 return $wgUrlProtocols;
1952         }
1953 }
1954
1955 /**
1956  * Safety wrapper around ini_get() for boolean settings.
1957  * The values returned from ini_get() are pre-normalized for settings
1958  * set via php.ini or php_flag/php_admin_flag... but *not*
1959  * for those set via php_value/php_admin_value.
1960  *
1961  * It's fairly common for people to use php_value instead of php_flag,
1962  * which can leave you with an 'off' setting giving a false positive
1963  * for code that just takes the ini_get() return value as a boolean.
1964  *
1965  * To make things extra interesting, setting via php_value accepts
1966  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
1967  * Unrecognized values go false... again opposite PHP's own coercion
1968  * from string to bool.
1969  *
1970  * Luckily, 'properly' set settings will always come back as '0' or '1',
1971  * so we only have to worry about them and the 'improper' settings.
1972  *
1973  * I frickin' hate PHP... :P
1974  *
1975  * @param string $setting
1976  * @return bool
1977  */
1978 function wfIniGetBool( $setting ) {
1979         $val = ini_get( $setting );
1980         // 'on' and 'true' can't have whitespace around them, but '1' can.
1981         return strtolower( $val ) == 'on'
1982                 || strtolower( $val ) == 'true'
1983                 || strtolower( $val ) == 'yes'
1984                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
1985 }
1986
1987 /**
1988  * Execute a shell command, with time and memory limits mirrored from the PHP
1989  * configuration if supported.
1990  * @param $cmd Command line, properly escaped for shell.
1991  * @param &$retval optional, will receive the program's exit code.
1992  *                 (non-zero is usually failure)
1993  * @return collected stdout as a string (trailing newlines stripped)
1994  */
1995 function wfShellExec( $cmd, &$retval=null ) {
1996         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
1997
1998         if( wfIniGetBool( 'safe_mode' ) ) {
1999                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2000                 $retval = 1;
2001                 return "Unable to run external programs in safe mode.";
2002         }
2003
2004         if ( php_uname( 's' ) == 'Linux' ) {
2005                 $time = intval( ini_get( 'max_execution_time' ) );
2006                 $mem = intval( $wgMaxShellMemory );
2007                 $filesize = intval( $wgMaxShellFileSize );
2008
2009                 if ( $time > 0 && $mem > 0 ) {
2010                         $script = "$IP/bin/ulimit4.sh";
2011                         if ( is_executable( $script ) ) {
2012                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2013                         }
2014                 }
2015         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
2016                 # This is a hack to work around PHP's flawed invocation of cmd.exe
2017                 # http://news.php.net/php.internals/21796
2018                 $cmd = '"' . $cmd . '"';
2019         }
2020         wfDebug( "wfShellExec: $cmd\n" );
2021
2022         $retval = 1; // error by default?
2023         ob_start();
2024         passthru( $cmd, $retval );
2025         $output = ob_get_contents();
2026         ob_end_clean();
2027         return $output;
2028
2029 }
2030
2031 /**
2032  * This function works like "use VERSION" in Perl, the program will die with a
2033  * backtrace if the current version of PHP is less than the version provided
2034  *
2035  * This is useful for extensions which due to their nature are not kept in sync
2036  * with releases, and might depend on other versions of PHP than the main code
2037  *
2038  * Note: PHP might die due to parsing errors in some cases before it ever
2039  *       manages to call this function, such is life
2040  *
2041  * @see perldoc -f use
2042  *
2043  * @param mixed $version The version to check, can be a string, an integer, or
2044  *                       a float
2045  */
2046 function wfUsePHP( $req_ver ) {
2047         $php_ver = PHP_VERSION;
2048
2049         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
2050                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2051 }
2052
2053 /**
2054  * This function works like "use VERSION" in Perl except it checks the version
2055  * of MediaWiki, the program will die with a backtrace if the current version
2056  * of MediaWiki is less than the version provided.
2057  *
2058  * This is useful for extensions which due to their nature are not kept in sync
2059  * with releases
2060  *
2061  * @see perldoc -f use
2062  *
2063  * @param mixed $version The version to check, can be a string, an integer, or
2064  *                       a float
2065  */
2066 function wfUseMW( $req_ver ) {
2067         global $wgVersion;
2068
2069         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
2070                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2071 }
2072
2073 /**
2074  * @deprecated use StringUtils::escapeRegexReplacement
2075  */
2076 function wfRegexReplacement( $string ) {
2077         return StringUtils::escapeRegexReplacement( $string );
2078 }
2079
2080 /**
2081  * Return the final portion of a pathname.
2082  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2083  * http://bugs.php.net/bug.php?id=33898
2084  *
2085  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2086  * We'll consider it so always, as we don't want \s in our Unix paths either.
2087  *
2088  * @param string $path
2089  * @param string $suffix to remove if present
2090  * @return string
2091  */
2092 function wfBaseName( $path, $suffix='' ) {
2093         $encSuffix = ($suffix == '')
2094                 ? ''
2095                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2096         $matches = array();
2097         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2098                 return $matches[1];
2099         } else {
2100                 return '';
2101         }
2102 }
2103
2104 /**
2105  * Generate a relative path name to the given file.
2106  * May explode on non-matching case-insensitive paths,
2107  * funky symlinks, etc.
2108  *
2109  * @param string $path Absolute destination path including target filename
2110  * @param string $from Absolute source path, directory only
2111  * @return string
2112  */
2113 function wfRelativePath( $path, $from ) {
2114         // Normalize mixed input on Windows...
2115         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2116         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2117
2118         // Trim trailing slashes -- fix for drive root
2119         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2120         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2121
2122         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2123         $against = explode( DIRECTORY_SEPARATOR, $from );
2124
2125         if( $pieces[0] !== $against[0] ) {
2126                 // Non-matching Windows drive letters?
2127                 // Return a full path.
2128                 return $path;
2129         }
2130
2131         // Trim off common prefix
2132         while( count( $pieces ) && count( $against )
2133                 && $pieces[0] == $against[0] ) {
2134                 array_shift( $pieces );
2135                 array_shift( $against );
2136         }
2137
2138         // relative dots to bump us to the parent
2139         while( count( $against ) ) {
2140                 array_unshift( $pieces, '..' );
2141                 array_shift( $against );
2142         }
2143
2144         array_push( $pieces, wfBaseName( $path ) );
2145
2146         return implode( DIRECTORY_SEPARATOR, $pieces );
2147 }
2148
2149 /**
2150  * array_merge() does awful things with "numeric" indexes, including
2151  * string indexes when happen to look like integers. When we want
2152  * to merge arrays with arbitrary string indexes, we don't want our
2153  * arrays to be randomly corrupted just because some of them consist
2154  * of numbers.
2155  *
2156  * Fuck you, PHP. Fuck you in the ear!
2157  *
2158  * @param array $array1, [$array2, [...]]
2159  * @return array
2160  */
2161 function wfArrayMerge( $array1/* ... */ ) {
2162         $out = $array1;
2163         for( $i = 1; $i < func_num_args(); $i++ ) {
2164                 foreach( func_get_arg( $i ) as $key => $value ) {
2165                         $out[$key] = $value;
2166                 }
2167         }
2168         return $out;
2169 }
2170
2171 /**
2172  * Make a URL index, appropriate for the el_index field of externallinks.
2173  */
2174 function wfMakeUrlIndex( $url ) {
2175         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2176         wfSuppressWarnings();
2177         $bits = parse_url( $url );
2178         wfRestoreWarnings();
2179         if ( !$bits ) {
2180                 return false;
2181         }
2182         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2183         $delimiter = '';
2184         if ( in_array( $bits['scheme'] . '://' , $wgUrlProtocols ) ) {
2185                 $delimiter = '://';
2186         } elseif ( in_array( $bits['scheme'] .':' , $wgUrlProtocols ) ) {
2187                 $delimiter = ':';
2188                 // parse_url detects for news: and mailto: the host part of an url as path
2189                 // We have to correct this wrong detection
2190                 if ( isset ( $bits['path'] ) ) {
2191                         $bits['host'] = $bits['path'];
2192                         $bits['path'] = '';
2193                 }
2194         } else {
2195                 return false;
2196         }
2197
2198         // Reverse the labels in the hostname, convert to lower case
2199         // For emails reverse domainpart only
2200         if ( $bits['scheme'] == 'mailto' ) {
2201                 $mailparts = explode( '@', $bits['host'], 2 );
2202                 if ( count($mailparts) === 2 ) {
2203                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2204                 } else {
2205                         // No domain specified, don't mangle it
2206                         $domainpart = '';
2207                 }
2208                 $reversedHost = $domainpart . '@' . $mailparts[0];
2209         } else {
2210                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2211         }
2212         // Add an extra dot to the end
2213         // Why? Is it in wrong place in mailto links?
2214         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2215                 $reversedHost .= '.';
2216         }
2217         // Reconstruct the pseudo-URL
2218         $prot = $bits['scheme'];
2219         $index = "$prot$delimiter$reversedHost";
2220         // Leave out user and password. Add the port, path, query and fragment
2221         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
2222         if ( isset( $bits['path'] ) ) {
2223                 $index .= $bits['path'];
2224         } else {
2225                 $index .= '/';
2226         }
2227         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
2228         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
2229         return $index;
2230 }
2231
2232 /**
2233  * Do any deferred updates and clear the list
2234  * TODO: This could be in Wiki.php if that class made any sense at all
2235  */
2236 function wfDoUpdates()
2237 {
2238         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2239         foreach ( $wgDeferredUpdateList as $update ) {
2240                 $update->doUpdate();
2241         }
2242         foreach ( $wgPostCommitUpdateList as $update ) {
2243                 $update->doUpdate();
2244         }
2245         $wgDeferredUpdateList = array();
2246         $wgPostCommitUpdateList = array();
2247 }
2248
2249 /**
2250  * @deprecated use StringUtils::explodeMarkup
2251  */
2252 function wfExplodeMarkup( $separator, $text ) {
2253         return StringUtils::explodeMarkup( $separator, $text );
2254 }
2255
2256 /**
2257  * Convert an arbitrarily-long digit string from one numeric base
2258  * to another, optionally zero-padding to a minimum column width.
2259  *
2260  * Supports base 2 through 36; digit values 10-36 are represented
2261  * as lowercase letters a-z. Input is case-insensitive.
2262  *
2263  * @param $input string of digits
2264  * @param $sourceBase int 2-36
2265  * @param $destBase int 2-36
2266  * @param $pad int 1 or greater
2267  * @param $lowercase bool
2268  * @return string or false on invalid input
2269  */
2270 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2271         $input = strval( $input );
2272         if( $sourceBase < 2 ||
2273                 $sourceBase > 36 ||
2274                 $destBase < 2 ||
2275                 $destBase > 36 ||
2276                 $pad < 1 ||
2277                 $sourceBase != intval( $sourceBase ) ||
2278                 $destBase != intval( $destBase ) ||
2279                 $pad != intval( $pad ) ||
2280                 !is_string( $input ) ||
2281                 $input == '' ) {
2282                 return false;
2283         }
2284         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2285         $inDigits = array();
2286         $outChars = '';
2287
2288         // Decode and validate input string
2289         $input = strtolower( $input );
2290         for( $i = 0; $i < strlen( $input ); $i++ ) {
2291                 $n = strpos( $digitChars, $input{$i} );
2292                 if( $n === false || $n > $sourceBase ) {
2293                         return false;
2294                 }
2295                 $inDigits[] = $n;
2296         }
2297
2298         // Iterate over the input, modulo-ing out an output digit
2299         // at a time until input is gone.
2300         while( count( $inDigits ) ) {
2301                 $work = 0;
2302                 $workDigits = array();
2303
2304                 // Long division...
2305                 foreach( $inDigits as $digit ) {
2306                         $work *= $sourceBase;
2307                         $work += $digit;
2308
2309                         if( $work < $destBase ) {
2310                                 // Gonna need to pull another digit.
2311                                 if( count( $workDigits ) ) {
2312                                         // Avoid zero-padding; this lets us find
2313                                         // the end of the input very easily when
2314                                         // length drops to zero.
2315                                         $workDigits[] = 0;
2316                                 }
2317                         } else {
2318                                 // Finally! Actual division!
2319                                 $workDigits[] = intval( $work / $destBase );
2320
2321                                 // Isn't it annoying that most programming languages
2322                                 // don't have a single divide-and-remainder operator,
2323                                 // even though the CPU implements it that way?
2324                                 $work = $work % $destBase;
2325                         }
2326                 }
2327
2328                 // All that division leaves us with a remainder,
2329                 // which is conveniently our next output digit.
2330                 $outChars .= $digitChars[$work];
2331
2332                 // And we continue!
2333                 $inDigits = $workDigits;
2334         }
2335
2336         while( strlen( $outChars ) < $pad ) {
2337                 $outChars .= '0';
2338         }
2339
2340         return strrev( $outChars );
2341 }
2342
2343 /**
2344  * Create an object with a given name and an array of construct parameters
2345  * @param string $name
2346  * @param array $p parameters
2347  */
2348 function wfCreateObject( $name, $p ){
2349         $p = array_values( $p );
2350         switch ( count( $p ) ) {
2351                 case 0:
2352                         return new $name;
2353                 case 1:
2354                         return new $name( $p[0] );
2355                 case 2:
2356                         return new $name( $p[0], $p[1] );
2357                 case 3:
2358                         return new $name( $p[0], $p[1], $p[2] );
2359                 case 4:
2360                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2361                 case 5:
2362                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2363                 case 6:
2364                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2365                 default:
2366                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2367         }
2368 }
2369
2370 /**
2371  * Alias for modularized function
2372  * @deprecated Use Http::get() instead
2373  */
2374 function wfGetHTTP( $url, $timeout = 'default' ) {
2375         wfDeprecated(__FUNCTION__);
2376         return Http::get( $url, $timeout );
2377 }
2378
2379 /**
2380  * Alias for modularized function
2381  * @deprecated Use Http::isLocalURL() instead
2382  */
2383 function wfIsLocalURL( $url ) {
2384         wfDeprecated(__FUNCTION__);
2385         return Http::isLocalURL( $url );
2386 }
2387
2388 function wfHttpOnlySafe() {
2389         global $wgHttpOnlyBlacklist;
2390         if( !version_compare("5.2", PHP_VERSION, "<") )
2391                 return false;
2392
2393         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2394                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2395                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2396                                 return false;
2397                         }
2398                 }
2399         }
2400
2401         return true;
2402 }
2403
2404 /**
2405  * Initialise php session
2406  */
2407 function wfSetupSession() {
2408         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
2409         if( $wgSessionsInMemcached ) {
2410                 require_once( 'MemcachedSessions.php' );
2411         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2412                 # If it's left on 'user' or another setting from another
2413                 # application, it will end up failing. Try to recover.
2414                 ini_set ( 'session.save_handler', 'files' );
2415         }
2416         $httpOnlySafe = wfHttpOnlySafe();
2417         wfDebugLog( 'cookie',
2418                 'session_set_cookie_params: "' . implode( '", "',
2419                         array(
2420                                 0,
2421                                 $wgCookiePath,
2422                                 $wgCookieDomain,
2423                                 $wgCookieSecure,
2424                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2425         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2426                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2427         } else {
2428                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2429                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2430         }
2431         session_cache_limiter( 'private, must-revalidate' );
2432         wfSuppressWarnings();
2433         session_start();
2434         wfRestoreWarnings();
2435 }
2436
2437 /**
2438  * Get an object from the precompiled serialized directory
2439  *
2440  * @return mixed The variable on success, false on failure
2441  */
2442 function wfGetPrecompiledData( $name ) {
2443         global $IP;
2444
2445         $file = "$IP/serialized/$name";
2446         if ( file_exists( $file ) ) {
2447                 $blob = file_get_contents( $file );
2448                 if ( $blob ) {
2449                         return unserialize( $blob );
2450                 }
2451         }
2452         return false;
2453 }
2454
2455 function wfGetCaller( $level = 2 ) {
2456         $backtrace = wfDebugBacktrace();
2457         if ( isset( $backtrace[$level] ) ) {
2458                 return wfFormatStackFrame($backtrace[$level]);
2459         } else {
2460                 $caller = 'unknown';
2461         }
2462         return $caller;
2463 }
2464
2465 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2466 function wfGetAllCallers() {
2467         return implode('/', array_map('wfFormatStackFrame',array_reverse(wfDebugBacktrace())));
2468 }
2469
2470 /** Return a string representation of frame */
2471 function wfFormatStackFrame($frame) {
2472         return isset( $frame["class"] )?
2473                 $frame["class"]."::".$frame["function"]:
2474                 $frame["function"];
2475 }
2476
2477 /**
2478  * Get a cache key
2479  */
2480 function wfMemcKey( /*... */ ) {
2481         $args = func_get_args();
2482         $key = wfWikiID() . ':' . implode( ':', $args );
2483         return $key;
2484 }
2485
2486 /**
2487  * Get a cache key for a foreign DB
2488  */
2489 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2490         $args = array_slice( func_get_args(), 2 );
2491         if ( $prefix ) {
2492                 $key = "$db-$prefix:" . implode( ':', $args );
2493         } else {
2494                 $key = $db . ':' . implode( ':', $args );
2495         }
2496         return $key;
2497 }
2498
2499 /**
2500  * Get an ASCII string identifying this wiki
2501  * This is used as a prefix in memcached keys
2502  */
2503 function wfWikiID( $db = null ) {
2504         if( $db instanceof Database ) {
2505                 return $db->getWikiID();
2506         } else {
2507         global $wgDBprefix, $wgDBname;
2508                 if ( $wgDBprefix ) {
2509                         return "$wgDBname-$wgDBprefix";
2510                 } else {
2511                         return $wgDBname;
2512                 }
2513         }
2514 }
2515
2516 /**
2517  * Split a wiki ID into DB name and table prefix
2518  */
2519 function wfSplitWikiID( $wiki ) {
2520         $bits = explode( '-', $wiki, 2 );
2521         if ( count( $bits ) < 2 ) {
2522                 $bits[] = '';
2523         }
2524         return $bits;
2525 }
2526
2527 /*
2528  * Get a Database object.
2529  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2530  *                master (for write queries), DB_SLAVE for potentially lagged
2531  *                read queries, or an integer >= 0 for a particular server.
2532  *
2533  * @param mixed $groups Query groups. An array of group names that this query
2534  *              belongs to. May contain a single string if the query is only
2535  *              in one group.
2536  *
2537  * @param string $wiki The wiki ID, or false for the current wiki
2538  *
2539  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
2540  * will always return the same object, unless the underlying connection or load
2541  * balancer is manually destroyed.
2542  */
2543 function &wfGetDB( $db = DB_LAST, $groups = array(), $wiki = false ) {
2544         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2545 }
2546
2547 /**
2548  * Get a load balancer object.
2549  *
2550  * @param array $groups List of query groups
2551  * @param string $wiki Wiki ID, or false for the current wiki
2552  * @return LoadBalancer
2553  */
2554 function wfGetLB( $wiki = false ) {
2555         return wfGetLBFactory()->getMainLB( $wiki );
2556 }
2557
2558 /**
2559  * Get the load balancer factory object
2560  */
2561 function &wfGetLBFactory() {
2562         return LBFactory::singleton();
2563 }
2564
2565 /**
2566  * Find a file.
2567  * Shortcut for RepoGroup::singleton()->findFile()
2568  * @param mixed $title Title object or string. May be interwiki.
2569  * @param mixed $time Requested time for an archived image, or false for the
2570  *                    current version. An image object will be returned which
2571  *                    was created at the specified time.
2572  * @param mixed $flags FileRepo::FIND_ flags
2573  * @return File, or false if the file does not exist
2574  */
2575 function wfFindFile( $title, $time = false, $flags = 0 ) {
2576         return RepoGroup::singleton()->findFile( $title, $time, $flags );
2577 }
2578
2579 /**
2580  * Get an object referring to a locally registered file.
2581  * Returns a valid placeholder object if the file does not exist.
2582  */
2583 function wfLocalFile( $title ) {
2584         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2585 }
2586
2587 /**
2588  * Should low-performance queries be disabled?
2589  *
2590  * @return bool
2591  */
2592 function wfQueriesMustScale() {
2593         global $wgMiserMode;
2594         return $wgMiserMode
2595                 || ( SiteStats::pages() > 100000
2596                 && SiteStats::edits() > 1000000
2597                 && SiteStats::users() > 10000 );
2598 }
2599
2600 /**
2601  * Get the path to a specified script file, respecting file
2602  * extensions; this is a wrapper around $wgScriptExtension etc.
2603  *
2604  * @param string $script Script filename, sans extension
2605  * @return string
2606  */
2607 function wfScript( $script = 'index' ) {
2608         global $wgScriptPath, $wgScriptExtension;
2609         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
2610 }
2611
2612 /**
2613  * Convenience function converts boolean values into "true"
2614  * or "false" (string) values
2615  *
2616  * @param bool $value
2617  * @return string
2618  */
2619 function wfBoolToStr( $value ) {
2620         return $value ? 'true' : 'false';
2621 }
2622
2623 /**
2624  * Load an extension messages file
2625  *
2626  * @param string $extensionName Name of extension to load messages from\for.
2627  * @param string $langcode Language to load messages for, or false for default
2628  *                         behvaiour (en, content language and user language).
2629  * @since r24808 (v1.11) Using this method of loading extension messages will not work
2630  * on MediaWiki prior to that
2631  */
2632 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
2633         global $wgExtensionMessagesFiles, $wgMessageCache, $wgLang, $wgContLang;
2634
2635         #For recording whether extension message files have been loaded in a given language.
2636         static $loaded = array();
2637
2638         if( !array_key_exists( $extensionName, $loaded ) ) {
2639                 $loaded[$extensionName] = array();
2640         }
2641
2642         if ( !isset($wgExtensionMessagesFiles[$extensionName]) ) {
2643                 throw new MWException( "Messages file for extensions $extensionName is not defined" );
2644         }
2645
2646         if( !$langcode && !array_key_exists( '*', $loaded[$extensionName] ) ) {
2647                 # Just do en, content language and user language.
2648                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], false );
2649                 # Mark that they have been loaded.
2650                 $loaded[$extensionName]['en'] = true;
2651                 $loaded[$extensionName][$wgLang->getCode()] = true;
2652                 $loaded[$extensionName][$wgContLang->getCode()] = true;
2653                 # Mark that this part has been done to avoid weird if statements.
2654                 $loaded[$extensionName]['*'] = true;
2655         } elseif( is_string( $langcode ) && !array_key_exists( $langcode, $loaded[$extensionName] ) ) {
2656                 # Load messages for specified language.
2657                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], $langcode );
2658                 # Mark that they have been loaded.
2659                 $loaded[$extensionName][$langcode] = true;
2660         }
2661 }
2662
2663 /**
2664  * Get a platform-independent path to the null file, e.g.
2665  * /dev/null
2666  *
2667  * @return string
2668  */
2669 function wfGetNull() {
2670         return wfIsWindows()
2671                 ? 'NUL'
2672                 : '/dev/null';
2673 }
2674
2675 /**
2676  * Displays a maxlag error
2677  *
2678  * @param string $host Server that lags the most
2679  * @param int $lag Maxlag (actual)
2680  * @param int $maxLag Maxlag (requested)
2681  */
2682 function wfMaxlagError( $host, $lag, $maxLag ) {
2683         global $wgShowHostnames;
2684         header( 'HTTP/1.1 503 Service Unavailable' );
2685         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
2686         header( 'X-Database-Lag: ' . intval( $lag ) );
2687         header( 'Content-Type: text/plain' );
2688         if( $wgShowHostnames ) {
2689                 echo "Waiting for $host: $lag seconds lagged\n";
2690         } else {
2691                 echo "Waiting for a database server: $lag seconds lagged\n";
2692         }
2693 }
2694
2695 /**
2696  * Throws an E_USER_NOTICE saying that $function is deprecated
2697  * @param string $function
2698  * @return null
2699  */
2700 function wfDeprecated( $function ) {
2701         global $wgDebugLogFile;
2702         if ( !$wgDebugLogFile ) {
2703                 return;
2704         }
2705         $callers = wfDebugBacktrace();
2706         if( isset( $callers[2] ) ){
2707                 $callerfunc = $callers[2];
2708                 $callerfile = $callers[1];
2709                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ){
2710                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
2711                 } else {
2712                         $file = '(internal function)';
2713                 }
2714                 $func = '';
2715                 if( isset( $callerfunc['class'] ) )
2716                         $func .= $callerfunc['class'] . '::';
2717                 $func .= @$callerfunc['function'];
2718                 $msg = "Use of $function is deprecated. Called from $func in $file";
2719         } else {
2720                 $msg = "Use of $function is deprecated.";
2721         }
2722         wfDebug( "$msg\n" );
2723 }
2724
2725 /**
2726  * Sleep until the worst slave's replication lag is less than or equal to
2727  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
2728  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
2729  * a no-op if there are no slaves.
2730  *
2731  * Every time the function has to wait for a slave, it will print a message to
2732  * that effect (and then sleep for a little while), so it's probably not best
2733  * to use this outside maintenance scripts in its present form.
2734  *
2735  * @param int $maxLag
2736  * @return null
2737  */
2738 function wfWaitForSlaves( $maxLag ) {
2739         if( $maxLag ) {
2740                 $lb = wfGetLB();
2741                 list( $host, $lag ) = $lb->getMaxLag();
2742                 while( $lag > $maxLag ) {
2743                         $name = @gethostbyaddr( $host );
2744                         if( $name !== false ) {
2745                                 $host = $name;
2746                         }
2747                         print "Waiting for $host (lagged $lag seconds)...\n";
2748                         sleep($maxLag);
2749                         list( $host, $lag ) = $lb->getMaxLag();
2750                 }
2751         }
2752 }
2753
2754 /** Generate a random 32-character hexadecimal token.
2755  * @param mixed $salt Some sort of salt, if necessary, to add to random characters before hashing.
2756  */
2757 function wfGenerateToken( $salt = '' ) {
2758         $salt = serialize($salt);
2759
2760         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
2761 }
2762
2763 /**
2764  * Replace all invalid characters with -
2765  * @param mixed $title Filename to process
2766  */
2767 function wfStripIllegalFilenameChars( $name ) {
2768         $name = wfBaseName( $name );
2769         $name = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $name );
2770         return $name;
2771 }