includes/GlobalFunctions.php

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