includes/GlobalFunctions.php

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