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 through htmlspecialchars
 550  *  <i>escapenoentities</i>: same, but allows entity references like &nbsp; through
 551  *  <i>replaceafter</i>: parameters are substituted after parsing or escaping
 552  *  <i>parsemag</i>: transform the message using magic phrases
 553  *  <i>content</i>: fetch message for content language instead of interface
 554  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 555  */
 556 function wfMsgExt( $key, $options ) {
 557         global $wgOut, $wgParser;
 558
 559         $args = func_get_args();
 560         array_shift( $args );
 561         array_shift( $args );
 562
 563         if( !is_array($options) ) {
 564                 $options = array($options);
 565         }
 566
 567         $forContent = false;
 568         if( in_array('content', $options) ) {
 569                 $forContent = true;
 570         }
 571
 572         $string = wfMsgGetKey( $key, /*DB*/true, $forContent, /*Transform*/false );
 573
 574         if( !in_array('replaceafter', $options) ) {
 575                 $string = wfMsgReplaceArgs( $string, $args );
 576         }
 577
 578         if( in_array('parse', $options) ) {
 579                 $string = $wgOut->parse( $string, true, !$forContent );
 580         } elseif ( in_array('parseinline', $options) ) {
 581                 $string = $wgOut->parse( $string, true, !$forContent );
 582                 $m = array();
 583                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 584                         $string = $m[1];
 585                 }
 586         } elseif ( in_array('parsemag', $options) ) {
 587                 global $wgMessageCache;
 588                 if ( isset( $wgMessageCache ) ) {
 589                         $string = $wgMessageCache->transform( $string, !$forContent );
 590                 }
 591         }
 592
 593         if ( in_array('escape', $options) ) {
 594                 $string = htmlspecialchars ( $string );
 595         } elseif ( in_array( 'escapenoentities', $options ) ) {
 596                 $string = htmlspecialchars( $string );
 597                 $string = str_replace( '&amp;', '&', $string );
 598                 $string = Sanitizer::normalizeCharReferences( $string );
 599         }
 600
 601         if( in_array('replaceafter', $options) ) {
 602                 $string = wfMsgReplaceArgs( $string, $args );
 603         }
 604
 605         return $string;
 606 }
 607
 608
 609 /**
 610  * Just like exit() but makes a note of it.
 611  * Commits open transactions except if the error parameter is set
 612  *
 613  * @deprecated Please return control to the caller or throw an exception
 614  */
 615 function wfAbruptExit( $error = false ){
 616         global $wgLoadBalancer;
 617         static $called = false;
 618         if ( $called ){
 619                 exit( -1 );
 620         }
 621         $called = true;
 622
 623         $bt = wfDebugBacktrace();
 624         if( $bt ) {
 625                 for($i = 0; $i < count($bt) ; $i++){
 626                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 627                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 628                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 629                 }
 630         } else {
 631                 wfDebug('WARNING: Abrupt exit\n');
 632         }
 633
 634         wfLogProfilingData();
 635
 636         if ( !$error ) {
 637                 $wgLoadBalancer->closeAll();
 638         }
 639         exit( -1 );
 640 }
 641
 642 /**
 643  * @deprecated Please return control the caller or throw an exception
 644  */
 645 function wfErrorExit() {
 646         wfAbruptExit( true );
 647 }
 648
 649 /**
 650  * Print a simple message and die, returning nonzero to the shell if any.
 651  * Plain die() fails to return nonzero to the shell if you pass a string.
 652  * @param string $msg
 653  */
 654 function wfDie( $msg='' ) {
 655         echo $msg;
 656         die( 1 );
 657 }
 658
 659 /**
 660  * Throw a debugging exception. This function previously once exited the process,
 661  * but now throws an exception instead, with similar results.
 662  *
 663  * @param string $msg Message shown when dieing.
 664  */
 665 function wfDebugDieBacktrace( $msg = '' ) {
 666         throw new MWException( $msg );
 667 }
 668
 669 /**
 670  * Fetch server name for use in error reporting etc.
 671  * Use real server name if available, so we know which machine
 672  * in a server farm generated the current page.
 673  * @return string
 674  */
 675 function wfHostname() {
 676         if ( function_exists( 'posix_uname' ) ) {
 677                 // This function not present on Windows
 678                 $uname = @posix_uname();
 679         } else {
 680                 $uname = false;
 681         }
 682         if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 683                 return $uname['nodename'];
 684         } else {
 685                 # This may be a virtual server.
 686                 return $_SERVER['SERVER_NAME'];
 687         }
 688 }
 689
 690         /**
 691          * Returns a HTML comment with the elapsed time since request.
 692          * This method has no side effects.
 693          * @return string
 694          */
 695         function wfReportTime() {
 696                 global $wgRequestTime, $wgShowHostnames;
 697
 698                 $now = wfTime();
 699                 $elapsed = $now - $wgRequestTime;
 700
 701                 return $wgShowHostnames
 702                         ? sprintf( "<!-- Served by %s in %01.3f secs. -->", wfHostname(), $elapsed )
 703                         : sprintf( "<!-- Served in %01.3f secs. -->", $elapsed );
 704         }
 705
 706 /**
 707  * Safety wrapper for debug_backtrace().
 708  *
 709  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 710  * murky circumstances, which may be triggered in part by stub objects
 711  * or other fancy talkin'.
 712  *
 713  * Will return an empty array if Zend Optimizer is detected, otherwise
 714  * the output from debug_backtrace() (trimmed).
 715  *
 716  * @return array of backtrace information
 717  */
 718 function wfDebugBacktrace() {
 719         if( extension_loaded( 'Zend Optimizer' ) ) {
 720                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 721                 return array();
 722         } else {
 723                 return array_slice( debug_backtrace(), 1 );
 724         }
 725 }
 726
 727 function wfBacktrace() {
 728         global $wgCommandLineMode;
 729
 730         if ( $wgCommandLineMode ) {
 731                 $msg = '';
 732         } else {
 733                 $msg = "<ul>\n";
 734         }
 735         $backtrace = wfDebugBacktrace();
 736         foreach( $backtrace as $call ) {
 737                 if( isset( $call['file'] ) ) {
 738                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 739                         $file = $f[count($f)-1];
 740                 } else {
 741                         $file = '-';
 742                 }
 743                 if( isset( $call['line'] ) ) {
 744                         $line = $call['line'];
 745                 } else {
 746                         $line = '-';
 747                 }
 748                 if ( $wgCommandLineMode ) {
 749                         $msg .= "$file line $line calls ";
 750                 } else {
 751                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 752                 }
 753                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 754                 $msg .= $call['function'] . '()';
 755
 756                 if ( $wgCommandLineMode ) {
 757                         $msg .= "\n";
 758                 } else {
 759                         $msg .= "</li>\n";
 760                 }
 761         }
 762         if ( $wgCommandLineMode ) {
 763                 $msg .= "\n";
 764         } else {
 765                 $msg .= "</ul>\n";
 766         }
 767
 768         return $msg;
 769 }
 770
 771
 772 /* Some generic result counters, pulled out of SearchEngine */
 773
 774
 775 /**
 776  * @todo document
 777  */
 778 function wfShowingResults( $offset, $limit ) {
 779         global $wgLang;
 780         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 781 }
 782
 783 /**
 784  * @todo document
 785  */
 786 function wfShowingResultsNum( $offset, $limit, $num ) {
 787         global $wgLang;
 788         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 789 }
 790
 791 /**
 792  * @todo document
 793  */
 794 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 795         global $wgLang;
 796         $fmtLimit = $wgLang->formatNum( $limit );
 797         $prev = wfMsg( 'prevn', $fmtLimit );
 798         $next = wfMsg( 'nextn', $fmtLimit );
 799
 800         if( is_object( $link ) ) {
 801                 $title =& $link;
 802         } else {
 803                 $title = Title::newFromText( $link );
 804                 if( is_null( $title ) ) {
 805                         return false;
 806                 }
 807         }
 808
 809         if ( 0 != $offset ) {
 810                 $po = $offset - $limit;
 811                 if ( $po < 0 ) { $po = 0; }
 812                 $q = "limit={$limit}&offset={$po}";
 813                 if ( '' != $query ) { $q .= '&'.$query; }
 814                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
 815         } else { $plink = $prev; }
 816
 817         $no = $offset + $limit;
 818         $q = 'limit='.$limit.'&offset='.$no;
 819         if ( '' != $query ) { $q .= '&'.$query; }
 820
 821         if ( $atend ) {
 822                 $nlink = $next;
 823         } else {
 824                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
 825         }
 826         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 827           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 828           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 829           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 830           wfNumLink( $offset, 500, $title, $query );
 831
 832         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 833 }
 834
 835 /**
 836  * @todo document
 837  */
 838 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 839         global $wgLang;
 840         if ( '' == $query ) { $q = ''; }
 841         else { $q = $query.'&'; }
 842         $q .= 'limit='.$limit.'&offset='.$offset;
 843
 844         $fmtLimit = $wgLang->formatNum( $limit );
 845         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-numlink\">{$fmtLimit}</a>";
 846         return $s;
 847 }
 848
 849 /**
 850  * @todo document
 851  * @todo FIXME: we may want to blacklist some broken browsers
 852  *
 853  * @return bool Whereas client accept gzip compression
 854  */
 855 function wfClientAcceptsGzip() {
 856         global $wgUseGzip;
 857         if( $wgUseGzip ) {
 858                 # FIXME: we may want to blacklist some broken browsers
 859                 $m = array();
 860                 if( preg_match(
 861                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 862                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 863                         $m ) ) {
 864                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 865                         wfDebug( " accepts gzip\n" );
 866                         return true;
 867                 }
 868         }
 869         return false;
 870 }
 871
 872 /**
 873  * Obtain the offset and limit values from the request string;
 874  * used in special pages
 875  *
 876  * @param $deflimit Default limit if none supplied
 877  * @param $optionname Name of a user preference to check against
 878  * @return array
 879  *
 880  */
 881 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 882         global $wgRequest;
 883         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 884 }
 885
 886 /**
 887  * Escapes the given text so that it may be output using addWikiText()
 888  * without any linking, formatting, etc. making its way through. This
 889  * is achieved by substituting certain characters with HTML entities.
 890  * As required by the callers, <nowiki> is not used. It currently does
 891  * not filter out characters which have special meaning only at the
 892  * start of a line, such as "*".
 893  *
 894  * @param string $text Text to be escaped
 895  */
 896 function wfEscapeWikiText( $text ) {
 897         $text = str_replace(
 898                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
 899                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
 900                 htmlspecialchars($text) );
 901         return $text;
 902 }
 903
 904 /**
 905  * @todo document
 906  */
 907 function wfQuotedPrintable( $string, $charset = '' ) {
 908         # Probably incomplete; see RFC 2045
 909         if( empty( $charset ) ) {
 910                 global $wgInputEncoding;
 911                 $charset = $wgInputEncoding;
 912         }
 913         $charset = strtoupper( $charset );
 914         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 915
 916         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 917         $replace = $illegal . '\t ?_';
 918         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 919         $out = "=?$charset?Q?";
 920         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 921         $out .= '?=';
 922         return $out;
 923 }
 924
 925
 926 /**
 927  * @todo document
 928  * @return float
 929  */
 930 function wfTime() {
 931         return microtime(true);
 932 }
 933
 934 /**
 935  * Sets dest to source and returns the original value of dest
 936  * If source is NULL, it just returns the value, it doesn't set the variable
 937  */
 938 function wfSetVar( &$dest, $source ) {
 939         $temp = $dest;
 940         if ( !is_null( $source ) ) {
 941                 $dest = $source;
 942         }
 943         return $temp;
 944 }
 945
 946 /**
 947  * As for wfSetVar except setting a bit
 948  */
 949 function wfSetBit( &$dest, $bit, $state = true ) {
 950         $temp = (bool)($dest & $bit );
 951         if ( !is_null( $state ) ) {
 952                 if ( $state ) {
 953                         $dest |= $bit;
 954                 } else {
 955                         $dest &= ~$bit;
 956                 }
 957         }
 958         return $temp;
 959 }
 960
 961 /**
 962  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 963  * "days=7&limit=100". Options in the first array override options in the second.
 964  * Options set to "" will not be output.
 965  */
 966 function wfArrayToCGI( $array1, $array2 = NULL )
 967 {
 968         if ( !is_null( $array2 ) ) {
 969                 $array1 = $array1 + $array2;
 970         }
 971
 972         $cgi = '';
 973         foreach ( $array1 as $key => $value ) {
 974                 if ( '' !== $value ) {
 975                         if ( '' != $cgi ) {
 976                                 $cgi .= '&';
 977                         }
 978                         $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 979                 }
 980         }
 981         return $cgi;
 982 }
 983
 984 /**
 985  * Append a query string to an existing URL, which may or may not already
 986  * have query string parameters already. If so, they will be combined.
 987  *
 988  * @param string $url
 989  * @param string $query
 990  * @return string
 991  */
 992 function wfAppendQuery( $url, $query ) {
 993         if( $query != '' ) {
 994                 if( false === strpos( $url, '?' ) ) {
 995                         $url .= '?';
 996                 } else {
 997                         $url .= '&';
 998                 }
 999                 $url .= $query;
1000         }
1001         return $url;
1002 }
1003
1004 /**
1005  * This is obsolete, use SquidUpdate::purge()
1006  * @deprecated
1007  */
1008 function wfPurgeSquidServers ($urlArr) {
1009         SquidUpdate::purge( $urlArr );
1010 }
1011
1012 /**
1013  * Windows-compatible version of escapeshellarg()
1014  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1015  * function puts single quotes in regardless of OS
1016  */
1017 function wfEscapeShellArg( ) {
1018         $args = func_get_args();
1019         $first = true;
1020         $retVal = '';
1021         foreach ( $args as $arg ) {
1022                 if ( !$first ) {
1023                         $retVal .= ' ';
1024                 } else {
1025                         $first = false;
1026                 }
1027
1028                 if ( wfIsWindows() ) {
1029                         // Escaping for an MSVC-style command line parser
1030                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1031                         // Double the backslashes before any double quotes. Escape the double quotes.
1032                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1033                         $arg = '';
1034                         $delim = false;
1035                         foreach ( $tokens as $token ) {
1036                                 if ( $delim ) {
1037                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1038                                 } else {
1039                                         $arg .= $token;
1040                                 }
1041                                 $delim = !$delim;
1042                         }
1043                         // Double the backslashes before the end of the string, because
1044                         // we will soon add a quote
1045                         $m = array();
1046                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1047                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1048                         }
1049
1050                         // Add surrounding quotes
1051                         $retVal .= '"' . $arg . '"';
1052                 } else {
1053                         $retVal .= escapeshellarg( $arg );
1054                 }
1055         }
1056         return $retVal;
1057 }
1058
1059 /**
1060  * wfMerge attempts to merge differences between three texts.
1061  * Returns true for a clean merge and false for failure or a conflict.
1062  */
1063 function wfMerge( $old, $mine, $yours, &$result ){
1064         global $wgDiff3;
1065
1066         # This check may also protect against code injection in
1067         # case of broken installations.
1068         if(! file_exists( $wgDiff3 ) ){
1069                 wfDebug( "diff3 not found\n" );
1070                 return false;
1071         }
1072
1073         # Make temporary files
1074         $td = wfTempDir();
1075         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1076         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1077         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1078
1079         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1080         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1081         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1082
1083         # Check for a conflict
1084         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1085           wfEscapeShellArg( $mytextName ) . ' ' .
1086           wfEscapeShellArg( $oldtextName ) . ' ' .
1087           wfEscapeShellArg( $yourtextName );
1088         $handle = popen( $cmd, 'r' );
1089
1090         if( fgets( $handle, 1024 ) ){
1091                 $conflict = true;
1092         } else {
1093                 $conflict = false;
1094         }
1095         pclose( $handle );
1096
1097         # Merge differences
1098         $cmd = $wgDiff3 . ' -a -e --merge ' .
1099           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1100         $handle = popen( $cmd, 'r' );
1101         $result = '';
1102         do {
1103                 $data = fread( $handle, 8192 );
1104                 if ( strlen( $data ) == 0 ) {
1105                         break;
1106                 }
1107                 $result .= $data;
1108         } while ( true );
1109         pclose( $handle );
1110         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1111
1112         if ( $result === '' && $old !== '' && $conflict == false ) {
1113                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1114                 $conflict = true;
1115         }
1116         return ! $conflict;
1117 }
1118
1119 /**
1120  * @todo document
1121  */
1122 function wfVarDump( $var ) {
1123         global $wgOut;
1124         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1125         if ( headers_sent() || !@is_object( $wgOut ) ) {
1126                 print $s;
1127         } else {
1128                 $wgOut->addHTML( $s );
1129         }
1130 }
1131
1132 /**
1133  * Provide a simple HTTP error.
1134  */
1135 function wfHttpError( $code, $label, $desc ) {
1136         global $wgOut;
1137         $wgOut->disable();
1138         header( "HTTP/1.0 $code $label" );
1139         header( "Status: $code $label" );
1140         $wgOut->sendCacheControl();
1141
1142         header( 'Content-type: text/html; charset=utf-8' );
1143         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1144                 "<html><head><title>" .
1145                 htmlspecialchars( $label ) .
1146                 "</title></head><body><h1>" .
1147                 htmlspecialchars( $label ) .
1148                 "</h1><p>" .
1149                 nl2br( htmlspecialchars( $desc ) ) .
1150                 "</p></body></html>\n";
1151 }
1152
1153 /**
1154  * Clear away any user-level output buffers, discarding contents.
1155  *
1156  * Suitable for 'starting afresh', for instance when streaming
1157  * relatively large amounts of data without buffering, or wanting to
1158  * output image files without ob_gzhandler's compression.
1159  *
1160  * The optional $resetGzipEncoding parameter controls suppression of
1161  * the Content-Encoding header sent by ob_gzhandler; by default it
1162  * is left. See comments for wfClearOutputBuffers() for why it would
1163  * be used.
1164  *
1165  * Note that some PHP configuration options may add output buffer
1166  * layers which cannot be removed; these are left in place.
1167  *
1168  * @param bool $resetGzipEncoding
1169  */
1170 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1171         if( $resetGzipEncoding ) {
1172                 // Suppress Content-Encoding and Content-Length
1173                 // headers from 1.10+s wfOutputHandler
1174                 global $wgDisableOutputCompression;
1175                 $wgDisableOutputCompression = true;
1176         }
1177         while( $status = ob_get_status() ) {
1178                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1179                         // Probably from zlib.output_compression or other
1180                         // PHP-internal setting which can't be removed.
1181                         //
1182                         // Give up, and hope the result doesn't break
1183                         // output behavior.
1184                         break;
1185                 }
1186                 if( !ob_end_clean() ) {
1187                         // Could not remove output buffer handler; abort now
1188                         // to avoid getting in some kind of infinite loop.
1189                         break;
1190                 }
1191                 if( $resetGzipEncoding ) {
1192                         if( $status['name'] == 'ob_gzhandler' ) {
1193                                 // Reset the 'Content-Encoding' field set by this handler
1194                                 // so we can start fresh.
1195                                 header( 'Content-Encoding:' );
1196                         }
1197                 }
1198         }
1199 }
1200
1201 /**
1202  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1203  *
1204  * Clear away output buffers, but keep the Content-Encoding header
1205  * produced by ob_gzhandler, if any.
1206  *
1207  * This should be used for HTTP 304 responses, where you need to
1208  * preserve the Content-Encoding header of the real result, but
1209  * also need to suppress the output of ob_gzhandler to keep to spec
1210  * and avoid breaking Firefox in rare cases where the headers and
1211  * body are broken over two packets.
1212  */
1213 function wfClearOutputBuffers() {
1214         wfResetOutputBuffers( false );
1215 }
1216
1217 /**
1218  * Converts an Accept-* header into an array mapping string values to quality
1219  * factors
1220  */
1221 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1222         # No arg means accept anything (per HTTP spec)
1223         if( !$accept ) {
1224                 return array( $def => 1 );
1225         }
1226
1227         $prefs = array();
1228
1229         $parts = explode( ',', $accept );
1230
1231         foreach( $parts as $part ) {
1232                 # FIXME: doesn't deal with params like 'text/html; level=1'
1233                 @list( $value, $qpart ) = explode( ';', $part );
1234                 $match = array();
1235                 if( !isset( $qpart ) ) {
1236                         $prefs[$value] = 1;
1237                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1238                         $prefs[$value] = $match[1];
1239                 }
1240         }
1241
1242         return $prefs;
1243 }
1244
1245 /**
1246  * Checks if a given MIME type matches any of the keys in the given
1247  * array. Basic wildcards are accepted in the array keys.
1248  *
1249  * Returns the matching MIME type (or wildcard) if a match, otherwise
1250  * NULL if no match.
1251  *
1252  * @param string $type
1253  * @param array $avail
1254  * @return string
1255  * @private
1256  */
1257 function mimeTypeMatch( $type, $avail ) {
1258         if( array_key_exists($type, $avail) ) {
1259                 return $type;
1260         } else {
1261                 $parts = explode( '/', $type );
1262                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1263                         return $parts[0] . '/*';
1264                 } elseif( array_key_exists( '*/*', $avail ) ) {
1265                         return '*/*';
1266                 } else {
1267                         return NULL;
1268                 }
1269         }
1270 }
1271
1272 /**
1273  * Returns the 'best' match between a client's requested internet media types
1274  * and the server's list of available types. Each list should be an associative
1275  * array of type to preference (preference is a float between 0.0 and 1.0).
1276  * Wildcards in the types are acceptable.
1277  *
1278  * @param array $cprefs Client's acceptable type list
1279  * @param array $sprefs Server's offered types
1280  * @return string
1281  *
1282  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1283  * XXX: generalize to negotiate other stuff
1284  */
1285 function wfNegotiateType( $cprefs, $sprefs ) {
1286         $combine = array();
1287
1288         foreach( array_keys($sprefs) as $type ) {
1289                 $parts = explode( '/', $type );
1290                 if( $parts[1] != '*' ) {
1291                         $ckey = mimeTypeMatch( $type, $cprefs );
1292                         if( $ckey ) {
1293                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1294                         }
1295                 }
1296         }
1297
1298         foreach( array_keys( $cprefs ) as $type ) {
1299                 $parts = explode( '/', $type );
1300                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1301                         $skey = mimeTypeMatch( $type, $sprefs );
1302                         if( $skey ) {
1303                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1304                         }
1305                 }
1306         }
1307
1308         $bestq = 0;
1309         $besttype = NULL;
1310
1311         foreach( array_keys( $combine ) as $type ) {
1312                 if( $combine[$type] > $bestq ) {
1313                         $besttype = $type;
1314                         $bestq = $combine[$type];
1315                 }
1316         }
1317
1318         return $besttype;
1319 }
1320
1321 /**
1322  * Array lookup
1323  * Returns an array where the values in the first array are replaced by the
1324  * values in the second array with the corresponding keys
1325  *
1326  * @return array
1327  */
1328 function wfArrayLookup( $a, $b ) {
1329         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1330 }
1331
1332 /**
1333  * Convenience function; returns MediaWiki timestamp for the present time.
1334  * @return string
1335  */
1336 function wfTimestampNow() {
1337         # return NOW
1338         return wfTimestamp( TS_MW, time() );
1339 }
1340
1341 /**
1342  * Reference-counted warning suppression
1343  */
1344 function wfSuppressWarnings( $end = false ) {
1345         static $suppressCount = 0;
1346         static $originalLevel = false;
1347
1348         if ( $end ) {
1349                 if ( $suppressCount ) {
1350                         --$suppressCount;
1351                         if ( !$suppressCount ) {
1352                                 error_reporting( $originalLevel );
1353                         }
1354                 }
1355         } else {
1356                 if ( !$suppressCount ) {
1357                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1358                 }
1359                 ++$suppressCount;
1360         }
1361 }
1362
1363 /**
1364  * Restore error level to previous value
1365  */
1366 function wfRestoreWarnings() {
1367         wfSuppressWarnings( true );
1368 }
1369
1370 # Autodetect, convert and provide timestamps of various types
1371
1372 /**
1373  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1374  */
1375 define('TS_UNIX', 0);
1376
1377 /**
1378  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1379  */
1380 define('TS_MW', 1);
1381
1382 /**
1383  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1384  */
1385 define('TS_DB', 2);
1386
1387 /**
1388  * RFC 2822 format, for E-mail and HTTP headers
1389  */
1390 define('TS_RFC2822', 3);
1391
1392 /**
1393  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1394  *
1395  * This is used by Special:Export
1396  */
1397 define('TS_ISO_8601', 4);
1398
1399 /**
1400  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1401  *
1402  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1403  *       DateTime tag and page 36 for the DateTimeOriginal and
1404  *       DateTimeDigitized tags.
1405  */
1406 define('TS_EXIF', 5);
1407
1408 /**
1409  * Oracle format time.
1410  */
1411 define('TS_ORACLE', 6);
1412
1413 /**
1414  * Postgres format time.
1415  */
1416 define('TS_POSTGRES', 7);
1417
1418 /**
1419  * @param mixed $outputtype A timestamp in one of the supported formats, the
1420  *                          function will autodetect which format is supplied
1421  *                          and act accordingly.
1422  * @return string Time in the format specified in $outputtype
1423  */
1424 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1425         $uts = 0;
1426         $da = array();
1427         if ($ts==0) {
1428                 $uts=time();
1429         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1430                 # TS_DB
1431                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1432                             (int)$da[2],(int)$da[3],(int)$da[1]);
1433         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1434                 # TS_EXIF
1435                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1436                         (int)$da[2],(int)$da[3],(int)$da[1]);
1437         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1438                 # TS_MW
1439                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1440                             (int)$da[2],(int)$da[3],(int)$da[1]);
1441         } elseif (preg_match('/^(\d{1,13})$/D',$ts,$da)) {
1442                 # TS_UNIX
1443                 $uts = $ts;
1444         } elseif (preg_match('/^(\d{1,2})-(...)-(\d\d(\d\d)?) (\d\d)\.(\d\d)\.(\d\d)/', $ts, $da)) {
1445                 # TS_ORACLE
1446                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1447                                 str_replace("+00:00", "UTC", $ts)));
1448         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1449                 # TS_ISO_8601
1450                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1451                         (int)$da[2],(int)$da[3],(int)$da[1]);
1452         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1453                 # TS_POSTGRES
1454                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1455                 (int)$da[2],(int)$da[3],(int)$da[1]);
1456         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1457                 # TS_POSTGRES
1458                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1459                 (int)$da[2],(int)$da[3],(int)$da[1]);
1460         } else {
1461                 # Bogus value; fall back to the epoch...
1462                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1463                 $uts = 0;
1464         }
1465
1466
1467         switch($outputtype) {
1468                 case TS_UNIX:
1469                         return $uts;
1470                 case TS_MW:
1471                         return gmdate( 'YmdHis', $uts );
1472                 case TS_DB:
1473                         return gmdate( 'Y-m-d H:i:s', $uts );
1474                 case TS_ISO_8601:
1475                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1476                 // This shouldn't ever be used, but is included for completeness
1477                 case TS_EXIF:
1478                         return gmdate(  'Y:m:d H:i:s', $uts );
1479                 case TS_RFC2822:
1480                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1481                 case TS_ORACLE:
1482                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1483                 case TS_POSTGRES:
1484                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1485                 default:
1486                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1487         }
1488 }
1489
1490 /**
1491  * Return a formatted timestamp, or null if input is null.
1492  * For dealing with nullable timestamp columns in the database.
1493  * @param int $outputtype
1494  * @param string $ts
1495  * @return string
1496  */
1497 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1498         if( is_null( $ts ) ) {
1499                 return null;
1500         } else {
1501                 return wfTimestamp( $outputtype, $ts );
1502         }
1503 }
1504
1505 /**
1506  * Check if the operating system is Windows
1507  *
1508  * @return bool True if it's Windows, False otherwise.
1509  */
1510 function wfIsWindows() {
1511         if (substr(php_uname(), 0, 7) == 'Windows') {
1512                 return true;
1513         } else {
1514                 return false;
1515         }
1516 }
1517
1518 /**
1519  * Swap two variables
1520  */
1521 function swap( &$x, &$y ) {
1522         $z = $x;
1523         $x = $y;
1524         $y = $z;
1525 }
1526
1527 function wfGetCachedNotice( $name ) {
1528         global $wgOut, $parserMemc;
1529         $fname = 'wfGetCachedNotice';
1530         wfProfileIn( $fname );
1531
1532         $needParse = false;
1533
1534         if( $name === 'default' ) {
1535                 // special case
1536                 global $wgSiteNotice;
1537                 $notice = $wgSiteNotice;
1538                 if( empty( $notice ) ) {
1539                         wfProfileOut( $fname );
1540                         return false;
1541                 }
1542         } else {
1543                 $notice = wfMsgForContentNoTrans( $name );
1544                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1545                         wfProfileOut( $fname );
1546                         return( false );
1547                 }
1548         }
1549
1550         $cachedNotice = $parserMemc->get( wfMemcKey( $name ) );
1551         if( is_array( $cachedNotice ) ) {
1552                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1553                         $notice = $cachedNotice['html'];
1554                 } else {
1555                         $needParse = true;
1556                 }
1557         } else {
1558                 $needParse = true;
1559         }
1560
1561         if( $needParse ) {
1562                 if( is_object( $wgOut ) ) {
1563                         $parsed = $wgOut->parse( $notice );
1564                         $parserMemc->set( wfMemcKey( $name ), array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1565                         $notice = $parsed;
1566                 } else {
1567                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1568                         $notice = '';
1569                 }
1570         }
1571
1572         wfProfileOut( $fname );
1573         return $notice;
1574 }
1575
1576 function wfGetNamespaceNotice() {
1577         global $wgTitle;
1578
1579         # Paranoia
1580         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1581                 return "";
1582
1583         $fname = 'wfGetNamespaceNotice';
1584         wfProfileIn( $fname );
1585
1586         $key = "namespacenotice-" . $wgTitle->getNsText();
1587         $namespaceNotice = wfGetCachedNotice( $key );
1588         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1589                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1590         } else {
1591                 $namespaceNotice = "";
1592         }
1593
1594         wfProfileOut( $fname );
1595         return $namespaceNotice;
1596 }
1597
1598 function wfGetSiteNotice() {
1599         global $wgUser, $wgSiteNotice;
1600         $fname = 'wfGetSiteNotice';
1601         wfProfileIn( $fname );
1602         $siteNotice = '';
1603
1604         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1605                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1606                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1607                 } else {
1608                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1609                         if( !$anonNotice ) {
1610                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1611                         } else {
1612                                 $siteNotice = $anonNotice;
1613                         }
1614                 }
1615                 if( !$siteNotice ) {
1616                         $siteNotice = wfGetCachedNotice( 'default' );
1617                 }
1618         }
1619
1620         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1621         wfProfileOut( $fname );
1622         return $siteNotice;
1623 }
1624
1625 /**
1626  * BC wrapper for MimeMagic::singleton()
1627  * @deprecated
1628  */
1629 function &wfGetMimeMagic() {
1630         return MimeMagic::singleton();
1631 }
1632
1633 /**
1634  * Tries to get the system directory for temporary files.
1635  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1636  * and if none are set /tmp is returned as the generic Unix default.
1637  *
1638  * NOTE: When possible, use the tempfile() function to create temporary
1639  * files to avoid race conditions on file creation, etc.
1640  *
1641  * @return string
1642  */
1643 function wfTempDir() {
1644         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1645                 $tmp = getenv( $var );
1646                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1647                         return $tmp;
1648                 }
1649         }
1650         # Hope this is Unix of some kind!
1651         return '/tmp';
1652 }
1653
1654 /**
1655  * Make directory, and make all parent directories if they don't exist
1656  */
1657 function wfMkdirParents( $fullDir, $mode = 0777 ) {
1658         if( strval( $fullDir ) === '' )
1659                 return true;
1660         if( file_exists( $fullDir ) )
1661                 return true;
1662         return mkdir( str_replace( '/', DIRECTORY_SEPARATOR, $fullDir ), $mode, true );
1663 }
1664
1665 /**
1666  * Increment a statistics counter
1667  */
1668  function wfIncrStats( $key ) {
1669          global $wgMemc;
1670          $key = wfMemcKey( 'stats', $key );
1671          if ( is_null( $wgMemc->incr( $key ) ) ) {
1672                  $wgMemc->add( $key, 1 );
1673          }
1674  }
1675
1676 /**
1677  * @param mixed $nr The number to format
1678  * @param int $acc The number of digits after the decimal point, default 2
1679  * @param bool $round Whether or not to round the value, default true
1680  * @return float
1681  */
1682 function wfPercent( $nr, $acc = 2, $round = true ) {
1683         $ret = sprintf( "%.${acc}f", $nr );
1684         return $round ? round( $ret, $acc ) . '%' : "$ret%";
1685 }
1686
1687 /**
1688  * Encrypt a username/password.
1689  *
1690  * @param string $userid ID of the user
1691  * @param string $password Password of the user
1692  * @return string Hashed password
1693  */
1694 function wfEncryptPassword( $userid, $password ) {
1695         global $wgPasswordSalt;
1696         $p = md5( $password);
1697
1698         if($wgPasswordSalt)
1699                 return md5( "{$userid}-{$p}" );
1700         else
1701                 return $p;
1702 }
1703
1704 /**
1705  * Appends to second array if $value differs from that in $default
1706  */
1707 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
1708         if ( is_null( $changed ) ) {
1709                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
1710         }
1711         if ( $default[$key] !== $value ) {
1712                 $changed[$key] = $value;
1713         }
1714 }
1715
1716 /**
1717  * Since wfMsg() and co suck, they don't return false if the message key they
1718  * looked up didn't exist but a XHTML string, this function checks for the
1719  * nonexistance of messages by looking at wfMsg() output
1720  *
1721  * @param $msg      The message key looked up
1722  * @param $wfMsgOut The output of wfMsg*()
1723  * @return bool
1724  */
1725 function wfEmptyMsg( $msg, $wfMsgOut ) {
1726         return $wfMsgOut === htmlspecialchars( "<$msg>" );
1727 }
1728
1729 /**
1730  * Find out whether or not a mixed variable exists in a string
1731  *
1732  * @param mixed  needle
1733  * @param string haystack
1734  * @return bool
1735  */
1736 function in_string( $needle, $str ) {
1737         return strpos( $str, $needle ) !== false;
1738 }
1739
1740 function wfSpecialList( $page, $details ) {
1741         global $wgContLang;
1742         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
1743         return $page . $details;
1744 }
1745
1746 /**
1747  * Returns a regular expression of url protocols
1748  *
1749  * @return string
1750  */
1751 function wfUrlProtocols() {
1752         global $wgUrlProtocols;
1753
1754         // Support old-style $wgUrlProtocols strings, for backwards compatibility
1755         // with LocalSettings files from 1.5
1756         if ( is_array( $wgUrlProtocols ) ) {
1757                 $protocols = array();
1758                 foreach ($wgUrlProtocols as $protocol)
1759                         $protocols[] = preg_quote( $protocol, '/' );
1760
1761                 return implode( '|', $protocols );
1762         } else {
1763                 return $wgUrlProtocols;
1764         }
1765 }
1766
1767 /**
1768  * Safety wrapper around ini_get() for boolean settings.
1769  * The values returned from ini_get() are pre-normalized for settings
1770  * set via php.ini or php_flag/php_admin_flag... but *not*
1771  * for those set via php_value/php_admin_value.
1772  *
1773  * It's fairly common for people to use php_value instead of php_flag,
1774  * which can leave you with an 'off' setting giving a false positive
1775  * for code that just takes the ini_get() return value as a boolean.
1776  *
1777  * To make things extra interesting, setting via php_value accepts
1778  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
1779  * Unrecognized values go false... again opposite PHP's own coercion
1780  * from string to bool.
1781  *
1782  * Luckily, 'properly' set settings will always come back as '0' or '1',
1783  * so we only have to worry about them and the 'improper' settings.
1784  *
1785  * I frickin' hate PHP... :P
1786  *
1787  * @param string $setting
1788  * @return bool
1789  */
1790 function wfIniGetBool( $setting ) {
1791         $val = ini_get( $setting );
1792         // 'on' and 'true' can't have whitespace around them, but '1' can.
1793         return strtolower( $val ) == 'on'
1794                 || strtolower( $val ) == 'true'
1795                 || strtolower( $val ) == 'yes'
1796                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
1797 }
1798
1799 /**
1800  * Execute a shell command, with time and memory limits mirrored from the PHP
1801  * configuration if supported.
1802  * @param $cmd Command line, properly escaped for shell.
1803  * @param &$retval optional, will receive the program's exit code.
1804  *                 (non-zero is usually failure)
1805  * @return collected stdout as a string (trailing newlines stripped)
1806  */
1807 function wfShellExec( $cmd, &$retval=null ) {
1808         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
1809
1810         if( wfIniGetBool( 'safe_mode' ) ) {
1811                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
1812                 $retval = 1;
1813                 return "Unable to run external programs in safe mode.";
1814         }
1815
1816         if ( php_uname( 's' ) == 'Linux' ) {
1817                 $time = intval( ini_get( 'max_execution_time' ) );
1818                 $mem = intval( $wgMaxShellMemory );
1819                 $filesize = intval( $wgMaxShellFileSize );
1820
1821                 if ( $time > 0 && $mem > 0 ) {
1822                         $script = "$IP/bin/ulimit4.sh";
1823                         if ( is_executable( $script ) ) {
1824                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
1825                         }
1826                 }
1827         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
1828                 # This is a hack to work around PHP's flawed invocation of cmd.exe
1829                 # http://news.php.net/php.internals/21796
1830                 $cmd = '"' . $cmd . '"';
1831         }
1832         wfDebug( "wfShellExec: $cmd\n" );
1833
1834         $output = array();
1835         $retval = 1; // error by default?
1836         exec( $cmd, $output, $retval ); // returns the last line of output.
1837         return implode( "\n", $output );
1838
1839 }
1840
1841 /**
1842  * This function works like "use VERSION" in Perl, the program will die with a
1843  * backtrace if the current version of PHP is less than the version provided
1844  *
1845  * This is useful for extensions which due to their nature are not kept in sync
1846  * with releases, and might depend on other versions of PHP than the main code
1847  *
1848  * Note: PHP might die due to parsing errors in some cases before it ever
1849  *       manages to call this function, such is life
1850  *
1851  * @see perldoc -f use
1852  *
1853  * @param mixed $version The version to check, can be a string, an integer, or
1854  *                       a float
1855  */
1856 function wfUsePHP( $req_ver ) {
1857         $php_ver = PHP_VERSION;
1858
1859         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
1860                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
1861 }
1862
1863 /**
1864  * This function works like "use VERSION" in Perl except it checks the version
1865  * of MediaWiki, the program will die with a backtrace if the current version
1866  * of MediaWiki is less than the version provided.
1867  *
1868  * This is useful for extensions which due to their nature are not kept in sync
1869  * with releases
1870  *
1871  * @see perldoc -f use
1872  *
1873  * @param mixed $version The version to check, can be a string, an integer, or
1874  *                       a float
1875  */
1876 function wfUseMW( $req_ver ) {
1877         global $wgVersion;
1878
1879         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
1880                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
1881 }
1882
1883 /**
1884  * @deprecated use StringUtils::escapeRegexReplacement
1885  */
1886 function wfRegexReplacement( $string ) {
1887         return StringUtils::escapeRegexReplacement( $string );
1888 }
1889
1890 /**
1891  * Return the final portion of a pathname.
1892  * Reimplemented because PHP5's basename() is buggy with multibyte text.
1893  * http://bugs.php.net/bug.php?id=33898
1894  *
1895  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
1896  * We'll consider it so always, as we don't want \s in our Unix paths either.
1897  *
1898  * @param string $path
1899  * @param string $suffix to remove if present
1900  * @return string
1901  */
1902 function wfBaseName( $path, $suffix='' ) {
1903         $encSuffix = ($suffix == '')
1904                 ? ''
1905                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
1906         $matches = array();
1907         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
1908                 return $matches[1];
1909         } else {
1910                 return '';
1911         }
1912 }
1913
1914 /**
1915  * Generate a relative path name to the given file.
1916  * May explode on non-matching case-insensitive paths,
1917  * funky symlinks, etc.
1918  *
1919  * @param string $path Absolute destination path including target filename
1920  * @param string $from Absolute source path, directory only
1921  * @return string
1922  */
1923 function wfRelativePath( $path, $from ) {
1924         // Normalize mixed input on Windows...
1925         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
1926         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
1927
1928         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
1929         $against = explode( DIRECTORY_SEPARATOR, $from );
1930
1931         // Trim off common prefix
1932         while( count( $pieces ) && count( $against )
1933                 && $pieces[0] == $against[0] ) {
1934                 array_shift( $pieces );
1935                 array_shift( $against );
1936         }
1937
1938         // relative dots to bump us to the parent
1939         while( count( $against ) ) {
1940                 array_unshift( $pieces, '..' );
1941                 array_shift( $against );
1942         }
1943
1944         array_push( $pieces, wfBaseName( $path ) );
1945
1946         return implode( DIRECTORY_SEPARATOR, $pieces );
1947 }
1948
1949 /**
1950  * Make a URL index, appropriate for the el_index field of externallinks.
1951  */
1952 function wfMakeUrlIndex( $url ) {
1953         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
1954         $bits = parse_url( $url );
1955         wfSuppressWarnings();
1956         wfRestoreWarnings();
1957         if ( !$bits ) {
1958                 return false;
1959         }
1960         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
1961         $delimiter = '';
1962         if ( in_array( $bits['scheme'] . '://' , $wgUrlProtocols ) ) {
1963                 $delimiter = '://';
1964         } elseif ( in_array( $bits['scheme'] .':' , $wgUrlProtocols ) ) {
1965                 $delimiter = ':';
1966                 // parse_url detects for news: and mailto: the host part of an url as path
1967                 // We have to correct this wrong detection
1968                 if ( isset ( $bits['path'] ) ) {
1969                         $bits['host'] = $bits['path'];
1970                         $bits['path'] = '';
1971                 }
1972         } else {
1973                 return false;
1974         }
1975
1976         // Reverse the labels in the hostname, convert to lower case
1977         // For emails reverse domainpart only
1978         if ( $bits['scheme'] == 'mailto' ) {
1979                 $mailparts = explode( '@', $bits['host'] );
1980                 $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
1981                 $reversedHost = $domainpart . '@' . $mailparts[0];
1982         } else {
1983                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
1984         }
1985         // Add an extra dot to the end
1986         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
1987                 $reversedHost .= '.';
1988         }
1989         // Reconstruct the pseudo-URL
1990         $prot = $bits['scheme'];
1991         $index = "$prot$delimiter$reversedHost";
1992         // Leave out user and password. Add the port, path, query and fragment
1993         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
1994         if ( isset( $bits['path'] ) ) {
1995                 $index .= $bits['path'];
1996         } else {
1997                 $index .= '/';
1998         }
1999         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
2000         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
2001         return $index;
2002 }
2003
2004 /**
2005  * Do any deferred updates and clear the list
2006  * TODO: This could be in Wiki.php if that class made any sense at all
2007  */
2008 function wfDoUpdates()
2009 {
2010         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2011         foreach ( $wgDeferredUpdateList as $update ) {
2012                 $update->doUpdate();
2013         }
2014         foreach ( $wgPostCommitUpdateList as $update ) {
2015                 $update->doUpdate();
2016         }
2017         $wgDeferredUpdateList = array();
2018         $wgPostCommitUpdateList = array();
2019 }
2020
2021 /**
2022  * @deprecated use StringUtils::explodeMarkup
2023  */
2024 function wfExplodeMarkup( $separator, $text ) {
2025         return StringUtils::explodeMarkup( $separator, $text );
2026 }
2027
2028 /**
2029  * Convert an arbitrarily-long digit string from one numeric base
2030  * to another, optionally zero-padding to a minimum column width.
2031  *
2032  * Supports base 2 through 36; digit values 10-36 are represented
2033  * as lowercase letters a-z. Input is case-insensitive.
2034  *
2035  * @param $input string of digits
2036  * @param $sourceBase int 2-36
2037  * @param $destBase int 2-36
2038  * @param $pad int 1 or greater
2039  * @param $lowercase bool
2040  * @return string or false on invalid input
2041  */
2042 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2043         $input = strval( $input );
2044         if( $sourceBase < 2 ||
2045                 $sourceBase > 36 ||
2046                 $destBase < 2 ||
2047                 $destBase > 36 ||
2048                 $pad < 1 ||
2049                 $sourceBase != intval( $sourceBase ) ||
2050                 $destBase != intval( $destBase ) ||
2051                 $pad != intval( $pad ) ||
2052                 !is_string( $input ) ||
2053                 $input == '' ) {
2054                 return false;
2055         }
2056         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2057         $inDigits = array();
2058         $outChars = '';
2059
2060         // Decode and validate input string
2061         $input = strtolower( $input );
2062         for( $i = 0; $i < strlen( $input ); $i++ ) {
2063                 $n = strpos( $digitChars, $input{$i} );
2064                 if( $n === false || $n > $sourceBase ) {
2065                         return false;
2066                 }
2067                 $inDigits[] = $n;
2068         }
2069
2070         // Iterate over the input, modulo-ing out an output digit
2071         // at a time until input is gone.
2072         while( count( $inDigits ) ) {
2073                 $work = 0;
2074                 $workDigits = array();
2075
2076                 // Long division...
2077                 foreach( $inDigits as $digit ) {
2078                         $work *= $sourceBase;
2079                         $work += $digit;
2080
2081                         if( $work < $destBase ) {
2082                                 // Gonna need to pull another digit.
2083                                 if( count( $workDigits ) ) {
2084                                         // Avoid zero-padding; this lets us find
2085                                         // the end of the input very easily when
2086                                         // length drops to zero.
2087                                         $workDigits[] = 0;
2088                                 }
2089                         } else {
2090                                 // Finally! Actual division!
2091                                 $workDigits[] = intval( $work / $destBase );
2092
2093                                 // Isn't it annoying that most programming languages
2094                                 // don't have a single divide-and-remainder operator,
2095                                 // even though the CPU implements it that way?
2096                                 $work = $work % $destBase;
2097                         }
2098                 }
2099
2100                 // All that division leaves us with a remainder,
2101                 // which is conveniently our next output digit.
2102                 $outChars .= $digitChars[$work];
2103
2104                 // And we continue!
2105                 $inDigits = $workDigits;
2106         }
2107
2108         while( strlen( $outChars ) < $pad ) {
2109                 $outChars .= '0';
2110         }
2111
2112         return strrev( $outChars );
2113 }
2114
2115 /**
2116  * Create an object with a given name and an array of construct parameters
2117  * @param string $name
2118  * @param array $p parameters
2119  */
2120 function wfCreateObject( $name, $p ){
2121         $p = array_values( $p );
2122         switch ( count( $p ) ) {
2123                 case 0:
2124                         return new $name;
2125                 case 1:
2126                         return new $name( $p[0] );
2127                 case 2:
2128                         return new $name( $p[0], $p[1] );
2129                 case 3:
2130                         return new $name( $p[0], $p[1], $p[2] );
2131                 case 4:
2132                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2133                 case 5:
2134                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2135                 case 6:
2136                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2137                 default:
2138                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2139         }
2140 }
2141
2142 /**
2143  * Aliases for modularized functions
2144  */
2145 function wfGetHTTP( $url, $timeout = 'default' ) {
2146         return Http::get( $url, $timeout );
2147 }
2148 function wfIsLocalURL( $url ) {
2149         return Http::isLocalURL( $url );
2150 }
2151
2152 /**
2153  * Initialise php session
2154  */
2155 function wfSetupSession() {
2156         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure;
2157         if( $wgSessionsInMemcached ) {
2158                 require_once( 'MemcachedSessions.php' );
2159         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2160                 # If it's left on 'user' or another setting from another
2161                 # application, it will end up failing. Try to recover.
2162                 ini_set ( 'session.save_handler', 'files' );
2163         }
2164         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure);
2165         session_cache_limiter( 'private, must-revalidate' );
2166         @session_start();
2167 }
2168
2169 /**
2170  * Get an object from the precompiled serialized directory
2171  *
2172  * @return mixed The variable on success, false on failure
2173  */
2174 function wfGetPrecompiledData( $name ) {
2175         global $IP;
2176
2177         $file = "$IP/serialized/$name";
2178         if ( file_exists( $file ) ) {
2179                 $blob = file_get_contents( $file );
2180                 if ( $blob ) {
2181                         return unserialize( $blob );
2182                 }
2183         }
2184         return false;
2185 }
2186
2187 function wfGetCaller( $level = 2 ) {
2188         $backtrace = wfDebugBacktrace();
2189         if ( isset( $backtrace[$level] ) ) {
2190                 return wfFormatStackFrame($backtrace[$level]);
2191         } else {
2192                 $caller = 'unknown';
2193         }
2194         return $caller;
2195 }
2196
2197 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2198 function wfGetAllCallers() {
2199         return implode('/', array_map('wfFormatStackFrame',array_reverse(wfDebugBacktrace())));
2200 }
2201
2202 /** Return a string representation of frame */
2203 function wfFormatStackFrame($frame) {
2204         return isset( $frame["class"] )?
2205                 $frame["class"]."::".$frame["function"]:
2206                 $frame["function"];
2207 }
2208
2209 /**
2210  * Get a cache key
2211  */
2212 function wfMemcKey( /*... */ ) {
2213         global $wgDBprefix, $wgDBname;
2214         $args = func_get_args();
2215         if ( $wgDBprefix ) {
2216                 $key = "$wgDBname-$wgDBprefix:" . implode( ':', $args );
2217         } else {
2218                 $key = $wgDBname . ':' . implode( ':', $args );
2219         }
2220         return $key;
2221 }
2222
2223 /**
2224  * Get a cache key for a foreign DB
2225  */
2226 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2227         $args = array_slice( func_get_args(), 2 );
2228         if ( $prefix ) {
2229                 $key = "$db-$prefix:" . implode( ':', $args );
2230         } else {
2231                 $key = $db . ':' . implode( ':', $args );
2232         }
2233         return $key;
2234 }
2235
2236 /**
2237  * Get an ASCII string identifying this wiki
2238  * This is used as a prefix in memcached keys
2239  */
2240 function wfWikiID() {
2241         global $wgDBprefix, $wgDBname;
2242         if ( $wgDBprefix ) {
2243                 return "$wgDBname-$wgDBprefix";
2244         } else {
2245                 return $wgDBname;
2246         }
2247 }
2248
2249 /*
2250  * Get a Database object
2251  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2252  *                master (for write queries), DB_SLAVE for potentially lagged
2253  *                read queries, or an integer >= 0 for a particular server.
2254  *
2255  * @param mixed $groups Query groups. An array of group names that this query
2256  *              belongs to. May contain a single string if the query is only
2257  *              in one group.
2258  */
2259 function &wfGetDB( $db = DB_LAST, $groups = array() ) {
2260         global $wgLoadBalancer;
2261         $ret = $wgLoadBalancer->getConnection( $db, true, $groups );
2262         return $ret;
2263 }
2264
2265 /**
2266  * Find a file.
2267  * Shortcut for RepoGroup::singleton()->findFile()
2268  * @param mixed $title Title object or string. May be interwiki.
2269  * @param mixed $time Requested time for an archived image, or false for the
2270  *                    current version. An image object will be returned which
2271  *                    existed at or before the specified time.
2272  * @return File, or false if the file does not exist
2273  */
2274 function wfFindFile( $title, $time = false ) {
2275         return RepoGroup::singleton()->findFile( $title, $time );
2276 }
2277
2278 /**
2279  * Get an object referring to a locally registered file.
2280  * Returns a valid placeholder object if the file does not exist.
2281  */
2282 function wfLocalFile( $title ) {
2283         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2284 }
2285
2286 /**
2287  * Should low-performance queries be disabled?
2288  *
2289  * @return bool
2290  */
2291 function wfQueriesMustScale() {
2292         global $wgMiserMode;
2293         return $wgMiserMode
2294                 || ( SiteStats::pages() > 100000
2295                 && SiteStats::edits() > 1000000
2296                 && SiteStats::users() > 10000 );
2297 }
2298
2299 /**
2300  * Get the path to a specified script file, respecting file
2301  * extensions; this is a wrapper around $wgScriptExtension etc.
2302  *
2303  * @param string $script Script filename, sans extension
2304  * @return string
2305  */
2306 function wfScript( $script = 'index' ) {
2307         global $wgScriptPath, $wgScriptExtension;
2308         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
2309 }
2310
2311 /**
2312  * Convenience function converts boolean values into "true"
2313  * or "false" (string) values
2314  *
2315  * @param bool $value
2316  * @return string
2317  */
2318 function wfBoolToStr( $value ) {
2319         return $value ? 'true' : 'false';
2320 }
2321
2322 /**
2323  * Load an extension messages file
2324  */
2325 function wfLoadExtensionMessages( $extensionName ) {
2326         global $wgExtensionMessagesFiles, $wgMessageCache;
2327         if ( !empty( $wgExtensionMessagesFiles[$extensionName] ) ) {
2328                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName] );
2329                 // Prevent double-loading
2330                 $wgExtensionMessagesFiles[$extensionName] = false;
2331         }
2332 }
2333
2334 /**
2335  * Get a platform-independent path to the null file, e.g.
2336  * /dev/null
2337  *
2338  * @return string
2339  */
2340 function wfGetNull() {
2341         return wfIsWindows()
2342                 ? 'NUL'
2343                 : '/dev/null';
2344 }
2345
2346 /**
2347  * Displays a maxlag error
2348  *
2349  * @param string $host Server that lags the most
2350  * @param int $lag Maxlag (actual)
2351  * @param int $maxLag Maxlag (requested)
2352  */
2353 function wfMaxlagError( $host, $lag, $maxLag ) {
2354         global $wgShowHostnames;
2355         header( 'HTTP/1.1 503 Service Unavailable' );
2356         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
2357         header( 'X-Database-Lag: ' . intval( $lag ) );
2358         header( 'Content-Type: text/plain' );
2359         if( $wgShowHostnames ) {
2360                 echo "Waiting for $host: $lag seconds lagged\n";
2361         } else {
2362                 echo "Waiting for a database server: $lag seconds lagged\n";
2363         }
2364 }