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