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 /**
  12  * Some globals and requires needed
  13  */
  14
  15 /** Total number of articles */
  16 $wgNumberOfArticles = -1; # Unset
  17
  18 /** Total number of views */
  19 $wgTotalViews = -1;
  20
  21 /** Total number of edits */
  22 $wgTotalEdits = -1;
  23
  24
  25 global $IP;
  26 require_once dirname(__FILE__) . '/LogPage.php';
  27 require_once dirname(__FILE__) . '/normal/UtfNormalUtil.php';
  28 require_once dirname(__FILE__) . '/XmlFunctions.php';
  29
  30 /**
  31  * Compatibility functions
  32  *
  33  * We more or less support PHP 5.0.x and up.
  34  * Re-implementations of newer functions or functions in non-standard
  35  * PHP extensions may be included here.
  36  */
  37 if( !function_exists('iconv') ) {
  38         # iconv support is not in the default configuration and so may not be present.
  39         # Assume will only ever use utf-8 and iso-8859-1.
  40         # This will *not* work in all circumstances.
  41         function iconv( $from, $to, $string ) {
  42                 if(strcasecmp( $from, $to ) == 0) return $string;
  43                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  44                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  45                 return $string;
  46         }
  47 }
  48
  49 # UTF-8 substr function based on a PHP manual comment
  50 if ( !function_exists( 'mb_substr' ) ) {
  51         function mb_substr( $str, $start ) {
  52                 $ar = array();
  53                 preg_match_all( '/./us', $str, $ar );
  54
  55                 if( func_num_args() >= 3 ) {
  56                         $end = func_get_arg( 2 );
  57                         return join( '', array_slice( $ar[0], $start, $end ) );
  58                 } else {
  59                         return join( '', array_slice( $ar[0], $start ) );
  60                 }
  61         }
  62 }
  63
  64 if ( !function_exists( 'mb_strlen' ) ) {
  65         /**
  66          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
  67          * @param string $str
  68          * @param string $enc optional encoding; ignored
  69          * @return int
  70          */
  71         function new_mb_strlen( $str, $enc="" ) {
  72                 $counts = count_chars( $str );
  73                 $total = 0;
  74
  75                 // Count ASCII bytes
  76                 for( $i = 0; $i < 0x80; $i++ ) {
  77                         $total += $counts[$i];
  78                 }
  79
  80                 // Count multibyte sequence heads
  81                 for( $i = 0xc0; $i < 0xff; $i++ ) {
  82                         $total += $counts[$i];
  83                 }
  84                 return $total;
  85         }
  86 }
  87
  88 if ( !function_exists( 'array_diff_key' ) ) {
  89         /**
  90          * Exists in PHP 5.1.0+
  91          * Not quite compatible, two-argument version only
  92          * Null values will cause problems due to this use of isset()
  93          */
  94         function array_diff_key( $left, $right ) {
  95                 $result = $left;
  96                 foreach ( $left as $key => $unused ) {
  97                         if ( isset( $right[$key] ) ) {
  98                                 unset( $result[$key] );
  99                         }
 100                 }
 101                 return $result;
 102         }
 103 }
 104
 105
 106 /**
 107  * Wrapper for clone(), for compatibility with PHP4-friendly extensions.
 108  * PHP 5 won't let you declare a 'clone' function, even conditionally,
 109  * so it has to be a wrapper with a different name.
 110  */
 111 function wfClone( $object ) {
 112         return clone( $object );
 113 }
 114
 115 /**
 116  * Where as we got a random seed
 117  */
 118 $wgRandomSeeded = false;
 119
 120 /**
 121  * Seed Mersenne Twister
 122  * No-op for compatibility; only necessary in PHP < 4.2.0
 123  */
 124 function wfSeedRandom() {
 125         /* No-op */
 126 }
 127
 128 /**
 129  * Get a random decimal value between 0 and 1, in a way
 130  * not likely to give duplicate values for any realistic
 131  * number of articles.
 132  *
 133  * @return string
 134  */
 135 function wfRandom() {
 136         # The maximum random value is "only" 2^31-1, so get two random
 137         # values to reduce the chance of dupes
 138         $max = mt_getrandmax() + 1;
 139         $rand = number_format( (mt_rand() * $max + mt_rand())
 140                 / $max / $max, 12, '.', '' );
 141         return $rand;
 142 }
 143
 144 /**
 145  * We want / and : to be included as literal characters in our title URLs.
 146  * %2F in the page titles seems to fatally break for some reason.
 147  *
 148  * @param $s String:
 149  * @return string
 150 */
 151 function wfUrlencode ( $s ) {
 152         $s = urlencode( $s );
 153         $s = preg_replace( '/%3[Aa]/', ':', $s );
 154         $s = preg_replace( '/%2[Ff]/', '/', $s );
 155
 156         return $s;
 157 }
 158
 159 /**
 160  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 161  * In normal operation this is a NOP.
 162  *
 163  * Controlling globals:
 164  * $wgDebugLogFile - points to the log file
 165  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 166  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 167  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 168  *
 169  * @param $text String
 170  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 171  */
 172 function wfDebug( $text, $logonly = false ) {
 173         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 174         static $recursion = 0;
 175
 176         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 177         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 178                 return;
 179         }
 180
 181         if ( $wgDebugComments && !$logonly ) {
 182                 if ( !isset( $wgOut ) ) {
 183                         return;
 184                 }
 185                 if ( !StubObject::isRealObject( $wgOut ) ) {
 186                         if ( $recursion ) {
 187                                 return;
 188                         }
 189                         $recursion++;
 190                         $wgOut->_unstub();
 191                         $recursion--;
 192                 }
 193                 $wgOut->debug( $text );
 194         }
 195         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 196                 # Strip unprintables; they can switch terminal modes when binary data
 197                 # gets dumped, which is pretty annoying.
 198                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 199                 wfErrorLog( $text, $wgDebugLogFile );
 200         }
 201 }
 202
 203 /**
 204  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 205  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 206  *
 207  * @param $logGroup String
 208  * @param $text String
 209  * @param $public Bool: whether to log the event in the public log if no private
 210  *                     log file is specified, (default true)
 211  */
 212 function wfDebugLog( $logGroup, $text, $public = true ) {
 213         global $wgDebugLogGroups;
 214         if( $text{strlen( $text ) - 1} != "\n" ) $text .= "\n";
 215         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 216                 $time = wfTimestamp( TS_DB );
 217                 $wiki = wfWikiID();
 218                 wfErrorLog( "$time $wiki: $text", $wgDebugLogGroups[$logGroup] );
 219         } else if ( $public === true ) {
 220                 wfDebug( $text, true );
 221         }
 222 }
 223
 224 /**
 225  * Log for database errors
 226  * @param $text String: database error message.
 227  */
 228 function wfLogDBError( $text ) {
 229         global $wgDBerrorLog, $wgDBname;
 230         if ( $wgDBerrorLog ) {
 231                 $host = trim(`hostname`);
 232                 $text = date('D M j G:i:s T Y') . "\t$host\t$wgDBname\t$text";
 233                 wfErrorLog( $text, $wgDBerrorLog );
 234         }
 235 }
 236
 237 /**
 238  * Log to a file without getting "file size exceeded" signals
 239  */
 240 function wfErrorLog( $text, $file ) {
 241         wfSuppressWarnings();
 242         $exists = file_exists( $file );
 243         $size = filesize( $file );
 244         if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 245                 error_log( $text, 3, $file );
 246         }
 247         wfRestoreWarnings();
 248 }
 249
 250 /**
 251  * @todo document
 252  */
 253 function wfLogProfilingData() {
 254         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 255         global $wgProfiling, $wgUser;
 256         if ( $wgProfiling ) {
 257                 $now = wfTime();
 258                 $elapsed = $now - $wgRequestTime;
 259                 $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 260                 $forward = '';
 261                 if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 262                         $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 263                 if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 264                         $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 265                 if( !empty( $_SERVER['HTTP_FROM'] ) )
 266                         $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 267                 if( $forward )
 268                         $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 269                 // Don't unstub $wgUser at this late stage just for statistics purposes
 270                 if( StubObject::isRealObject($wgUser) && $wgUser->isAnon() )
 271                         $forward .= ' anon';
 272                 $log = sprintf( "%s\t%04.3f\t%s\n",
 273                   gmdate( 'YmdHis' ), $elapsed,
 274                   urldecode( $wgRequest->getRequestURL() . $forward ) );
 275                 if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 276                         wfErrorLog( $log . $prof, $wgDebugLogFile );
 277                 }
 278         }
 279 }
 280
 281 /**
 282  * Check if the wiki read-only lock file is present. This can be used to lock
 283  * off editing functions, but doesn't guarantee that the database will not be
 284  * modified.
 285  * @return bool
 286  */
 287 function wfReadOnly() {
 288         global $wgReadOnlyFile, $wgReadOnly;
 289
 290         if ( !is_null( $wgReadOnly ) ) {
 291                 return (bool)$wgReadOnly;
 292         }
 293         if ( '' == $wgReadOnlyFile ) {
 294                 return false;
 295         }
 296         // Set $wgReadOnly for faster access next time
 297         if ( is_file( $wgReadOnlyFile ) ) {
 298                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 299         } else {
 300                 $wgReadOnly = false;
 301         }
 302         return (bool)$wgReadOnly;
 303 }
 304
 305
 306 /**
 307  * Get a message from anywhere, for the current user language.
 308  *
 309  * Use wfMsgForContent() instead if the message should NOT
 310  * change depending on the user preferences.
 311  *
 312  * Note that the message may contain HTML, and is therefore
 313  * not safe for insertion anywhere. Some functions such as
 314  * addWikiText will do the escaping for you. Use wfMsgHtml()
 315  * if you need an escaped message.
 316  *
 317  * @param $key String: lookup key for the message, usually
 318  *    defined in languages/Language.php
 319  *
 320  * This function also takes extra optional parameters (not
 321  * shown in the function definition), which can by used to
 322  * insert variable text into the predefined message.
 323  */
 324 function wfMsg( $key ) {
 325         $args = func_get_args();
 326         array_shift( $args );
 327         return wfMsgReal( $key, $args, true );
 328 }
 329
 330 /**
 331  * Same as above except doesn't transform the message
 332  */
 333 function wfMsgNoTrans( $key ) {
 334         $args = func_get_args();
 335         array_shift( $args );
 336         return wfMsgReal( $key, $args, true, false, false );
 337 }
 338
 339 /**
 340  * Get a message from anywhere, for the current global language
 341  * set with $wgLanguageCode.
 342  *
 343  * Use this if the message should NOT change  dependent on the
 344  * language set in the user's preferences. This is the case for
 345  * most text written into logs, as well as link targets (such as
 346  * the name of the copyright policy page). Link titles, on the
 347  * other hand, should be shown in the UI language.
 348  *
 349  * Note that MediaWiki allows users to change the user interface
 350  * language in their preferences, but a single installation
 351  * typically only contains content in one language.
 352  *
 353  * Be wary of this distinction: If you use wfMsg() where you should
 354  * use wfMsgForContent(), a user of the software may have to
 355  * customize over 70 messages in order to, e.g., fix a link in every
 356  * possible language.
 357  *
 358  * @param $key String: lookup key for the message, usually
 359  *    defined in languages/Language.php
 360  */
 361 function wfMsgForContent( $key ) {
 362         global $wgForceUIMsgAsContentMsg;
 363         $args = func_get_args();
 364         array_shift( $args );
 365         $forcontent = true;
 366         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 367                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 368                 $forcontent = false;
 369         return wfMsgReal( $key, $args, true, $forcontent );
 370 }
 371
 372 /**
 373  * Same as above except doesn't transform the message
 374  */
 375 function wfMsgForContentNoTrans( $key ) {
 376         global $wgForceUIMsgAsContentMsg;
 377         $args = func_get_args();
 378         array_shift( $args );
 379         $forcontent = true;
 380         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 381                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 382                 $forcontent = false;
 383         return wfMsgReal( $key, $args, true, $forcontent, false );
 384 }
 385
 386 /**
 387  * Get a message from the language file, for the UI elements
 388  */
 389 function wfMsgNoDB( $key ) {
 390         $args = func_get_args();
 391         array_shift( $args );
 392         return wfMsgReal( $key, $args, false );
 393 }
 394
 395 /**
 396  * Get a message from the language file, for the content
 397  */
 398 function wfMsgNoDBForContent( $key ) {
 399         global $wgForceUIMsgAsContentMsg;
 400         $args = func_get_args();
 401         array_shift( $args );
 402         $forcontent = true;
 403         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 404                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 405                 $forcontent = false;
 406         return wfMsgReal( $key, $args, false, $forcontent );
 407 }
 408
 409
 410 /**
 411  * Really get a message
 412  * @param $key String: key to get.
 413  * @param $args
 414  * @param $useDB Boolean
 415  * @param $transform Boolean: Whether or not to transform the message.
 416  * @param $forContent Boolean
 417  * @return String: the requested message.
 418  */
 419 function wfMsgReal( $key, $args, $useDB = true, $forContent=false, $transform = true ) {
 420         $fname = 'wfMsgReal';
 421         wfProfileIn( $fname );
 422         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 423         $message = wfMsgReplaceArgs( $message, $args );
 424         wfProfileOut( $fname );
 425         return $message;
 426 }
 427
 428 /**
 429  * This function provides the message source for messages to be edited which are *not* stored in the database.
 430  * @param $key String:
 431  */
 432 function wfMsgWeirdKey ( $key ) {
 433         $subsource = str_replace ( ' ' , '_' , $key ) ;
 434         $source = wfMsgForContentNoTrans( $subsource ) ;
 435         if ( wfEmptyMsg( $subsource, $source) ) {
 436                 # Try again with first char lower case
 437                 $subsource = strtolower ( substr ( $subsource , 0 , 1 ) ) . substr ( $subsource , 1 ) ;
 438                 $source = wfMsgForContentNoTrans( $subsource ) ;
 439         }
 440         if ( wfEmptyMsg( $subsource, $source ) ) {
 441                 # Didn't work either, return blank text
 442                 $source = "" ;
 443         }
 444         return $source ;
 445 }
 446
 447 /**
 448  * Fetch a message string value, but don't replace any keys yet.
 449  * @param string $key
 450  * @param bool $useDB
 451  * @param bool $forContent
 452  * @return string
 453  * @private
 454  */
 455 function wfMsgGetKey( $key, $useDB, $forContent = false, $transform = true ) {
 456         global $wgParser, $wgContLang, $wgMessageCache, $wgLang;
 457
 458         if ( is_object( $wgMessageCache ) )
 459                 $transstat = $wgMessageCache->getTransform();
 460
 461         if( is_object( $wgMessageCache ) ) {
 462                 if ( ! $transform )
 463                         $wgMessageCache->disableTransform();
 464                 $message = $wgMessageCache->get( $key, $useDB, $forContent );
 465         } else {
 466                 if( $forContent ) {
 467                         $lang = &$wgContLang;
 468                 } else {
 469                         $lang = &$wgLang;
 470                 }
 471
 472                 wfSuppressWarnings();
 473
 474                 if( is_object( $lang ) ) {
 475                         $message = $lang->getMessage( $key );
 476                 } else {
 477                         $message = false;
 478                 }
 479                 wfRestoreWarnings();
 480                 if($message === false)
 481                         $message = Language::getMessage($key);
 482                 if ( $transform && strstr( $message, '{{' ) !== false ) {
 483                         $message = $wgParser->transformMsg($message, $wgMessageCache->getParserOptions() );
 484                 }
 485         }
 486
 487         if ( is_object( $wgMessageCache ) && ! $transform )
 488                 $wgMessageCache->setTransform( $transstat );
 489
 490         return $message;
 491 }
 492
 493 /**
 494  * Replace message parameter keys on the given formatted output.
 495  *
 496  * @param string $message
 497  * @param array $args
 498  * @return string
 499  * @private
 500  */
 501 function wfMsgReplaceArgs( $message, $args ) {
 502         # Fix windows line-endings
 503         # Some messages are split with explode("\n", $msg)
 504         $message = str_replace( "\r", '', $message );
 505
 506         // Replace arguments
 507         if ( count( $args ) ) {
 508                 if ( is_array( $args[0] ) ) {
 509                         foreach ( $args[0] as $key => $val ) {
 510                                 $message = str_replace( '$' . $key, $val, $message );
 511                         }
 512                 } else {
 513                         foreach( $args as $n => $param ) {
 514                                 $replacementKeys['$' . ($n + 1)] = $param;
 515                         }
 516                         $message = strtr( $message, $replacementKeys );
 517                 }
 518         }
 519
 520         return $message;
 521 }
 522
 523 /**
 524  * Return an HTML-escaped version of a message.
 525  * Parameter replacements, if any, are done *after* the HTML-escaping,
 526  * so parameters may contain HTML (eg links or form controls). Be sure
 527  * to pre-escape them if you really do want plaintext, or just wrap
 528  * the whole thing in htmlspecialchars().
 529  *
 530  * @param string $key
 531  * @param string ... parameters
 532  * @return string
 533  */
 534 function wfMsgHtml( $key ) {
 535         $args = func_get_args();
 536         array_shift( $args );
 537         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 538 }
 539
 540 /**
 541  * Return an HTML version of message
 542  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 543  * so parameters may contain HTML (eg links or form controls). Be sure
 544  * to pre-escape them if you really do want plaintext, or just wrap
 545  * the whole thing in htmlspecialchars().
 546  *
 547  * @param string $key
 548  * @param string ... parameters
 549  * @return string
 550  */
 551 function wfMsgWikiHtml( $key ) {
 552         global $wgOut;
 553         $args = func_get_args();
 554         array_shift( $args );
 555         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 556 }
 557
 558 /**
 559  * Returns message in the requested format
 560  * @param string $key Key of the message
 561  * @param array $options Processing rules:
 562  *  <i>parse<i>: parses wikitext to html
 563  *  <i>parseinline<i>: parses wikitext to html and removes the surrounding p's added by parser or tidy
 564  *  <i>escape<i>: filters message trough htmlspecialchars
 565  *  <i>replaceafter<i>: parameters are substituted after parsing or escaping
 566  *  <i>parsemag<i>: transform the message using magic phrases
 567  */
 568 function wfMsgExt( $key, $options ) {
 569         global $wgOut, $wgParser;
 570
 571         $args = func_get_args();
 572         array_shift( $args );
 573         array_shift( $args );
 574
 575         if( !is_array($options) ) {
 576                 $options = array($options);
 577         }
 578
 579         $string = wfMsgGetKey( $key, true, false, false );
 580
 581         if( !in_array('replaceafter', $options) ) {
 582                 $string = wfMsgReplaceArgs( $string, $args );
 583         }
 584
 585         if( in_array('parse', $options) ) {
 586                 $string = $wgOut->parse( $string, true, true );
 587         } elseif ( in_array('parseinline', $options) ) {
 588                 $string = $wgOut->parse( $string, true, true );
 589                 $m = array();
 590                 if( preg_match( "~^<p>(.*)\n?</p>$~", $string, $m ) ) {
 591                         $string = $m[1];
 592                 }
 593         } elseif ( in_array('parsemag', $options) ) {
 594                 global $wgMessageCache;
 595                 if ( isset( $wgMessageCache ) ) {
 596                         $string = $wgMessageCache->transform( $string );
 597                 }
 598         }
 599
 600         if ( in_array('escape', $options) ) {
 601                 $string = htmlspecialchars ( $string );
 602         }
 603
 604         if( in_array('replaceafter', $options) ) {
 605                 $string = wfMsgReplaceArgs( $string, $args );
 606         }
 607
 608         return $string;
 609 }
 610
 611
 612 /**
 613  * Just like exit() but makes a note of it.
 614  * Commits open transactions except if the error parameter is set
 615  *
 616  * @obsolete Please return control to the caller or throw an exception
 617  */
 618 function wfAbruptExit( $error = false ){
 619         global $wgLoadBalancer;
 620         static $called = false;
 621         if ( $called ){
 622                 exit( -1 );
 623         }
 624         $called = true;
 625
 626         $bt = wfDebugBacktrace();
 627         if( $bt ) {
 628                 for($i = 0; $i < count($bt) ; $i++){
 629                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 630                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 631                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 632                 }
 633         } else {
 634                 wfDebug('WARNING: Abrupt exit\n');
 635         }
 636
 637         wfLogProfilingData();
 638
 639         if ( !$error ) {
 640                 $wgLoadBalancer->closeAll();
 641         }
 642         exit( -1 );
 643 }
 644
 645 /**
 646  * @obsolete Please return control the caller or throw an exception
 647  */
 648 function wfErrorExit() {
 649         wfAbruptExit( true );
 650 }
 651
 652 /**
 653  * Print a simple message and die, returning nonzero to the shell if any.
 654  * Plain die() fails to return nonzero to the shell if you pass a string.
 655  * @param string $msg
 656  */
 657 function wfDie( $msg='' ) {
 658         echo $msg;
 659         die( 1 );
 660 }
 661
 662 /**
 663  * Throw a debugging exception. This function previously once exited the process,
 664  * but now throws an exception instead, with similar results.
 665  *
 666  * @param string $msg Message shown when dieing.
 667  */
 668 function wfDebugDieBacktrace( $msg = '' ) {
 669         throw new MWException( $msg );
 670 }
 671
 672 /**
 673  * Fetch server name for use in error reporting etc.
 674  * Use real server name if available, so we know which machine
 675  * in a server farm generated the current page.
 676  * @return string
 677  */
 678 function wfHostname() {
 679         if ( function_exists( 'posix_uname' ) ) {
 680                 // This function not present on Windows
 681                 $uname = @posix_uname();
 682         } else {
 683                 $uname = false;
 684         }
 685         if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 686                 return $uname['nodename'];
 687         } else {
 688                 # This may be a virtual server.
 689                 return $_SERVER['SERVER_NAME'];
 690         }
 691 }
 692
 693         /**
 694          * Returns a HTML comment with the elapsed time since request.
 695          * This method has no side effects.
 696          * @return string
 697          */
 698         function wfReportTime() {
 699                 global $wgRequestTime;
 700
 701                 $now = wfTime();
 702                 $elapsed = $now - $wgRequestTime;
 703
 704                 $com = sprintf( "<!-- Served by %s in %01.3f secs. -->",
 705                   wfHostname(), $elapsed );
 706                 return $com;
 707         }
 708
 709 /**
 710  * Safety wrapper for debug_backtrace().
 711  *
 712  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 713  * murky circumstances, which may be triggered in part by stub objects
 714  * or other fancy talkin'.
 715  *
 716  * Will return an empty array if Zend Optimizer is detected, otherwise
 717  * the output from debug_backtrace() (trimmed).
 718  *
 719  * @return array of backtrace information
 720  */
 721 function wfDebugBacktrace() {
 722         if( extension_loaded( 'Zend Optimizer' ) ) {
 723                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 724                 return array();
 725         } else {
 726                 return array_slice( debug_backtrace(), 1 );
 727         }
 728 }
 729
 730 function wfBacktrace() {
 731         global $wgCommandLineMode;
 732
 733         if ( $wgCommandLineMode ) {
 734                 $msg = '';
 735         } else {
 736                 $msg = "<ul>\n";
 737         }
 738         $backtrace = wfDebugBacktrace();
 739         foreach( $backtrace as $call ) {
 740                 if( isset( $call['file'] ) ) {
 741                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 742                         $file = $f[count($f)-1];
 743                 } else {
 744                         $file = '-';
 745                 }
 746                 if( isset( $call['line'] ) ) {
 747                         $line = $call['line'];
 748                 } else {
 749                         $line = '-';
 750                 }
 751                 if ( $wgCommandLineMode ) {
 752                         $msg .= "$file line $line calls ";
 753                 } else {
 754                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 755                 }
 756                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 757                 $msg .= $call['function'] . '()';
 758
 759                 if ( $wgCommandLineMode ) {
 760                         $msg .= "\n";
 761                 } else {
 762                         $msg .= "</li>\n";
 763                 }
 764         }
 765         if ( $wgCommandLineMode ) {
 766                 $msg .= "\n";
 767         } else {
 768                 $msg .= "</ul>\n";
 769         }
 770
 771         return $msg;
 772 }
 773
 774
 775 /* Some generic result counters, pulled out of SearchEngine */
 776
 777
 778 /**
 779  * @todo document
 780  */
 781 function wfShowingResults( $offset, $limit ) {
 782         global $wgLang;
 783         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 784 }
 785
 786 /**
 787  * @todo document
 788  */
 789 function wfShowingResultsNum( $offset, $limit, $num ) {
 790         global $wgLang;
 791         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 792 }
 793
 794 /**
 795  * @todo document
 796  */
 797 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 798         global $wgLang;
 799         $fmtLimit = $wgLang->formatNum( $limit );
 800         $prev = wfMsg( 'prevn', $fmtLimit );
 801         $next = wfMsg( 'nextn', $fmtLimit );
 802
 803         if( is_object( $link ) ) {
 804                 $title =& $link;
 805         } else {
 806                 $title = Title::newFromText( $link );
 807                 if( is_null( $title ) ) {
 808                         return false;
 809                 }
 810         }
 811
 812         if ( 0 != $offset ) {
 813                 $po = $offset - $limit;
 814                 if ( $po < 0 ) { $po = 0; }
 815                 $q = "limit={$limit}&offset={$po}";
 816                 if ( '' != $query ) { $q .= '&'.$query; }
 817                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$prev}</a>";
 818         } else { $plink = $prev; }
 819
 820         $no = $offset + $limit;
 821         $q = 'limit='.$limit.'&offset='.$no;
 822         if ( '' != $query ) { $q .= '&'.$query; }
 823
 824         if ( $atend ) {
 825                 $nlink = $next;
 826         } else {
 827                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$next}</a>";
 828         }
 829         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 830           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 831           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 832           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 833           wfNumLink( $offset, 500, $title, $query );
 834
 835         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 836 }
 837
 838 /**
 839  * @todo document
 840  */
 841 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 842         global $wgLang;
 843         if ( '' == $query ) { $q = ''; }
 844         else { $q = $query.'&'; }
 845         $q .= 'limit='.$limit.'&offset='.$offset;
 846
 847         $fmtLimit = $wgLang->formatNum( $limit );
 848         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\">{$fmtLimit}</a>";
 849         return $s;
 850 }
 851
 852 /**
 853  * @todo document
 854  * @todo FIXME: we may want to blacklist some broken browsers
 855  *
 856  * @return bool Whereas client accept gzip compression
 857  */
 858 function wfClientAcceptsGzip() {
 859         global $wgUseGzip;
 860         if( $wgUseGzip ) {
 861                 # FIXME: we may want to blacklist some broken browsers
 862                 $m = array();
 863                 if( preg_match(
 864                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 865                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 866                         $m ) ) {
 867                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 868                         wfDebug( " accepts gzip\n" );
 869                         return true;
 870                 }
 871         }
 872         return false;
 873 }
 874
 875 /**
 876  * Obtain the offset and limit values from the request string;
 877  * used in special pages
 878  *
 879  * @param $deflimit Default limit if none supplied
 880  * @param $optionname Name of a user preference to check against
 881  * @return array
 882  *
 883  */
 884 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 885         global $wgRequest;
 886         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 887 }
 888
 889 /**
 890  * Escapes the given text so that it may be output using addWikiText()
 891  * without any linking, formatting, etc. making its way through. This
 892  * is achieved by substituting certain characters with HTML entities.
 893  * As required by the callers, <nowiki> is not used. It currently does
 894  * not filter out characters which have special meaning only at the
 895  * start of a line, such as "*".
 896  *
 897  * @param string $text Text to be escaped
 898  */
 899 function wfEscapeWikiText( $text ) {
 900         $text = str_replace(
 901                 array( '[',     '|',      '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
 902                 array( '&#91;', '&#124;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
 903                 htmlspecialchars($text) );
 904         return $text;
 905 }
 906
 907 /**
 908  * @todo document
 909  */
 910 function wfQuotedPrintable( $string, $charset = '' ) {
 911         # Probably incomplete; see RFC 2045
 912         if( empty( $charset ) ) {
 913                 global $wgInputEncoding;
 914                 $charset = $wgInputEncoding;
 915         }
 916         $charset = strtoupper( $charset );
 917         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 918
 919         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 920         $replace = $illegal . '\t ?_';
 921         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 922         $out = "=?$charset?Q?";
 923         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 924         $out .= '?=';
 925         return $out;
 926 }
 927
 928
 929 /**
 930  * @todo document
 931  * @return float
 932  */
 933 function wfTime() {
 934         return microtime(true);
 935 }
 936
 937 /**
 938  * Sets dest to source and returns the original value of dest
 939  * If source is NULL, it just returns the value, it doesn't set the variable
 940  */
 941 function wfSetVar( &$dest, $source ) {
 942         $temp = $dest;
 943         if ( !is_null( $source ) ) {
 944                 $dest = $source;
 945         }
 946         return $temp;
 947 }
 948
 949 /**
 950  * As for wfSetVar except setting a bit
 951  */
 952 function wfSetBit( &$dest, $bit, $state = true ) {
 953         $temp = (bool)($dest & $bit );
 954         if ( !is_null( $state ) ) {
 955                 if ( $state ) {
 956                         $dest |= $bit;
 957                 } else {
 958                         $dest &= ~$bit;
 959                 }
 960         }
 961         return $temp;
 962 }
 963
 964 /**
 965  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 966  * "days=7&limit=100". Options in the first array override options in the second.
 967  * Options set to "" will not be output.
 968  */
 969 function wfArrayToCGI( $array1, $array2 = NULL )
 970 {
 971         if ( !is_null( $array2 ) ) {
 972                 $array1 = $array1 + $array2;
 973         }
 974
 975         $cgi = '';
 976         foreach ( $array1 as $key => $value ) {
 977                 if ( '' !== $value ) {
 978                         if ( '' != $cgi ) {
 979                                 $cgi .= '&';
 980                         }
 981                         $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 982                 }
 983         }
 984         return $cgi;
 985 }
 986
 987 /**
 988  * This is obsolete, use SquidUpdate::purge()
 989  * @deprecated
 990  */
 991 function wfPurgeSquidServers ($urlArr) {
 992         SquidUpdate::purge( $urlArr );
 993 }
 994
 995 /**
 996  * Windows-compatible version of escapeshellarg()
 997  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
 998  * function puts single quotes in regardless of OS
 999  */
1000 function wfEscapeShellArg( ) {
1001         $args = func_get_args();
1002         $first = true;
1003         $retVal = '';
1004         foreach ( $args as $arg ) {
1005                 if ( !$first ) {
1006                         $retVal .= ' ';
1007                 } else {
1008                         $first = false;
1009                 }
1010
1011                 if ( wfIsWindows() ) {
1012                         // Escaping for an MSVC-style command line parser
1013                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1014                         // Double the backslashes before any double quotes. Escape the double quotes.
1015                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1016                         $arg = '';
1017                         $delim = false;
1018                         foreach ( $tokens as $token ) {
1019                                 if ( $delim ) {
1020                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1021                                 } else {
1022                                         $arg .= $token;
1023                                 }
1024                                 $delim = !$delim;
1025                         }
1026                         // Double the backslashes before the end of the string, because
1027                         // we will soon add a quote
1028                         $m = array();
1029                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1030                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1031                         }
1032
1033                         // Add surrounding quotes
1034                         $retVal .= '"' . $arg . '"';
1035                 } else {
1036                         $retVal .= escapeshellarg( $arg );
1037                 }
1038         }
1039         return $retVal;
1040 }
1041
1042 /**
1043  * wfMerge attempts to merge differences between three texts.
1044  * Returns true for a clean merge and false for failure or a conflict.
1045  */
1046 function wfMerge( $old, $mine, $yours, &$result ){
1047         global $wgDiff3;
1048
1049         # This check may also protect against code injection in
1050         # case of broken installations.
1051         if(! file_exists( $wgDiff3 ) ){
1052                 wfDebug( "diff3 not found\n" );
1053                 return false;
1054         }
1055
1056         # Make temporary files
1057         $td = wfTempDir();
1058         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1059         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1060         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1061
1062         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1063         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1064         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1065
1066         # Check for a conflict
1067         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1068           wfEscapeShellArg( $mytextName ) . ' ' .
1069           wfEscapeShellArg( $oldtextName ) . ' ' .
1070           wfEscapeShellArg( $yourtextName );
1071         $handle = popen( $cmd, 'r' );
1072
1073         if( fgets( $handle, 1024 ) ){
1074                 $conflict = true;
1075         } else {
1076                 $conflict = false;
1077         }
1078         pclose( $handle );
1079
1080         # Merge differences
1081         $cmd = $wgDiff3 . ' -a -e --merge ' .
1082           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1083         $handle = popen( $cmd, 'r' );
1084         $result = '';
1085         do {
1086                 $data = fread( $handle, 8192 );
1087                 if ( strlen( $data ) == 0 ) {
1088                         break;
1089                 }
1090                 $result .= $data;
1091         } while ( true );
1092         pclose( $handle );
1093         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1094
1095         if ( $result === '' && $old !== '' && $conflict == false ) {
1096                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1097                 $conflict = true;
1098         }
1099         return ! $conflict;
1100 }
1101
1102 /**
1103  * @todo document
1104  */
1105 function wfVarDump( $var ) {
1106         global $wgOut;
1107         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1108         if ( headers_sent() || !@is_object( $wgOut ) ) {
1109                 print $s;
1110         } else {
1111                 $wgOut->addHTML( $s );
1112         }
1113 }
1114
1115 /**
1116  * Provide a simple HTTP error.
1117  */
1118 function wfHttpError( $code, $label, $desc ) {
1119         global $wgOut;
1120         $wgOut->disable();
1121         header( "HTTP/1.0 $code $label" );
1122         header( "Status: $code $label" );
1123         $wgOut->sendCacheControl();
1124
1125         header( 'Content-type: text/html; charset=utf-8' );
1126         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1127                 "<html><head><title>" .
1128                 htmlspecialchars( $label ) .
1129                 "</title></head><body><h1>" .
1130                 htmlspecialchars( $label ) .
1131                 "</h1><p>" .
1132                 nl2br( htmlspecialchars( $desc ) ) .
1133                 "</p></body></html>\n";
1134 }
1135
1136 /**
1137  * Clear away any user-level output buffers, discarding contents.
1138  *
1139  * Suitable for 'starting afresh', for instance when streaming
1140  * relatively large amounts of data without buffering, or wanting to
1141  * output image files without ob_gzhandler's compression.
1142  *
1143  * The optional $resetGzipEncoding parameter controls suppression of
1144  * the Content-Encoding header sent by ob_gzhandler; by default it
1145  * is left. See comments for wfClearOutputBuffers() for why it would
1146  * be used.
1147  *
1148  * Note that some PHP configuration options may add output buffer
1149  * layers which cannot be removed; these are left in place.
1150  *
1151  * @parameter bool $resetGzipEncoding
1152  */
1153 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1154         if( $resetGzipEncoding ) {
1155                 // Suppress Content-Encoding and Content-Length
1156                 // headers from 1.10+s wfOutputHandler
1157                 global $wgDisableOutputCompression;
1158                 $wgDisableOutputCompression = true;
1159         }
1160         while( $status = ob_get_status() ) {
1161                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1162                         // Probably from zlib.output_compression or other
1163                         // PHP-internal setting which can't be removed.
1164                         //
1165                         // Give up, and hope the result doesn't break
1166                         // output behavior.
1167                         break;
1168                 }
1169                 if( !ob_end_clean() ) {
1170                         // Could not remove output buffer handler; abort now
1171                         // to avoid getting in some kind of infinite loop.
1172                         break;
1173                 }
1174                 if( $resetGzipEncoding ) {
1175                         if( $status['name'] == 'ob_gzhandler' ) {
1176                                 // Reset the 'Content-Encoding' field set by this handler
1177                                 // so we can start fresh.
1178                                 header( 'Content-Encoding:' );
1179                         }
1180                 }
1181         }
1182 }
1183
1184 /**
1185  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1186  *
1187  * Clear away output buffers, but keep the Content-Encoding header
1188  * produced by ob_gzhandler, if any.
1189  *
1190  * This should be used for HTTP 304 responses, where you need to
1191  * preserve the Content-Encoding header of the real result, but
1192  * also need to suppress the output of ob_gzhandler to keep to spec
1193  * and avoid breaking Firefox in rare cases where the headers and
1194  * body are broken over two packets.
1195  */
1196 function wfClearOutputBuffers() {
1197         wfResetOutputBuffers( false );
1198 }
1199
1200 /**
1201  * Converts an Accept-* header into an array mapping string values to quality
1202  * factors
1203  */
1204 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1205         # No arg means accept anything (per HTTP spec)
1206         if( !$accept ) {
1207                 return array( $def => 1 );
1208         }
1209
1210         $prefs = array();
1211
1212         $parts = explode( ',', $accept );
1213
1214         foreach( $parts as $part ) {
1215                 # FIXME: doesn't deal with params like 'text/html; level=1'
1216                 @list( $value, $qpart ) = explode( ';', $part );
1217                 $match = array();
1218                 if( !isset( $qpart ) ) {
1219                         $prefs[$value] = 1;
1220                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1221                         $prefs[$value] = $match[1];
1222                 }
1223         }
1224
1225         return $prefs;
1226 }
1227
1228 /**
1229  * Checks if a given MIME type matches any of the keys in the given
1230  * array. Basic wildcards are accepted in the array keys.
1231  *
1232  * Returns the matching MIME type (or wildcard) if a match, otherwise
1233  * NULL if no match.
1234  *
1235  * @param string $type
1236  * @param array $avail
1237  * @return string
1238  * @private
1239  */
1240 function mimeTypeMatch( $type, $avail ) {
1241         if( array_key_exists($type, $avail) ) {
1242                 return $type;
1243         } else {
1244                 $parts = explode( '/', $type );
1245                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1246                         return $parts[0] . '/*';
1247                 } elseif( array_key_exists( '*/*', $avail ) ) {
1248                         return '*/*';
1249                 } else {
1250                         return NULL;
1251                 }
1252         }
1253 }
1254
1255 /**
1256  * Returns the 'best' match between a client's requested internet media types
1257  * and the server's list of available types. Each list should be an associative
1258  * array of type to preference (preference is a float between 0.0 and 1.0).
1259  * Wildcards in the types are acceptable.
1260  *
1261  * @param array $cprefs Client's acceptable type list
1262  * @param array $sprefs Server's offered types
1263  * @return string
1264  *
1265  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1266  * XXX: generalize to negotiate other stuff
1267  */
1268 function wfNegotiateType( $cprefs, $sprefs ) {
1269         $combine = array();
1270
1271         foreach( array_keys($sprefs) as $type ) {
1272                 $parts = explode( '/', $type );
1273                 if( $parts[1] != '*' ) {
1274                         $ckey = mimeTypeMatch( $type, $cprefs );
1275                         if( $ckey ) {
1276                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1277                         }
1278                 }
1279         }
1280
1281         foreach( array_keys( $cprefs ) as $type ) {
1282                 $parts = explode( '/', $type );
1283                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1284                         $skey = mimeTypeMatch( $type, $sprefs );
1285                         if( $skey ) {
1286                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1287                         }
1288                 }
1289         }
1290
1291         $bestq = 0;
1292         $besttype = NULL;
1293
1294         foreach( array_keys( $combine ) as $type ) {
1295                 if( $combine[$type] > $bestq ) {
1296                         $besttype = $type;
1297                         $bestq = $combine[$type];
1298                 }
1299         }
1300
1301         return $besttype;
1302 }
1303
1304 /**
1305  * Array lookup
1306  * Returns an array where the values in the first array are replaced by the
1307  * values in the second array with the corresponding keys
1308  *
1309  * @return array
1310  */
1311 function wfArrayLookup( $a, $b ) {
1312         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1313 }
1314
1315 /**
1316  * Convenience function; returns MediaWiki timestamp for the present time.
1317  * @return string
1318  */
1319 function wfTimestampNow() {
1320         # return NOW
1321         return wfTimestamp( TS_MW, time() );
1322 }
1323
1324 /**
1325  * Reference-counted warning suppression
1326  */
1327 function wfSuppressWarnings( $end = false ) {
1328         static $suppressCount = 0;
1329         static $originalLevel = false;
1330
1331         if ( $end ) {
1332                 if ( $suppressCount ) {
1333                         --$suppressCount;
1334                         if ( !$suppressCount ) {
1335                                 error_reporting( $originalLevel );
1336                         }
1337                 }
1338         } else {
1339                 if ( !$suppressCount ) {
1340                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1341                 }
1342                 ++$suppressCount;
1343         }
1344 }
1345
1346 /**
1347  * Restore error level to previous value
1348  */
1349 function wfRestoreWarnings() {
1350         wfSuppressWarnings( true );
1351 }
1352
1353 # Autodetect, convert and provide timestamps of various types
1354
1355 /**
1356  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1357  */
1358 define('TS_UNIX', 0);
1359
1360 /**
1361  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1362  */
1363 define('TS_MW', 1);
1364
1365 /**
1366  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1367  */
1368 define('TS_DB', 2);
1369
1370 /**
1371  * RFC 2822 format, for E-mail and HTTP headers
1372  */
1373 define('TS_RFC2822', 3);
1374
1375 /**
1376  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1377  *
1378  * This is used by Special:Export
1379  */
1380 define('TS_ISO_8601', 4);
1381
1382 /**
1383  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1384  *
1385  * @url http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1386  *       DateTime tag and page 36 for the DateTimeOriginal and
1387  *       DateTimeDigitized tags.
1388  */
1389 define('TS_EXIF', 5);
1390
1391 /**
1392  * Oracle format time.
1393  */
1394 define('TS_ORACLE', 6);
1395
1396 /**
1397  * Postgres format time.
1398  */
1399 define('TS_POSTGRES', 7);
1400
1401 /**
1402  * @param mixed $outputtype A timestamp in one of the supported formats, the
1403  *                          function will autodetect which format is supplied
1404  *                          and act accordingly.
1405  * @return string Time in the format specified in $outputtype
1406  */
1407 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1408         $uts = 0;
1409         $da = array();
1410         if ($ts==0) {
1411                 $uts=time();
1412         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1413                 # TS_DB
1414                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1415                             (int)$da[2],(int)$da[3],(int)$da[1]);
1416         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1417                 # TS_EXIF
1418                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1419                         (int)$da[2],(int)$da[3],(int)$da[1]);
1420         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1421                 # TS_MW
1422                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1423                             (int)$da[2],(int)$da[3],(int)$da[1]);
1424         } elseif (preg_match('/^(\d{1,13})$/D',$ts,$da)) {
1425                 # TS_UNIX
1426                 $uts = $ts;
1427         } elseif (preg_match('/^(\d{1,2})-(...)-(\d\d(\d\d)?) (\d\d)\.(\d\d)\.(\d\d)/', $ts, $da)) {
1428                 # TS_ORACLE
1429                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1430                                 str_replace("+00:00", "UTC", $ts)));
1431         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1432                 # TS_ISO_8601
1433                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1434                         (int)$da[2],(int)$da[3],(int)$da[1]);
1435         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1436                 # TS_POSTGRES
1437                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1438                 (int)$da[2],(int)$da[3],(int)$da[1]);
1439         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1440                 # TS_POSTGRES
1441                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1442                 (int)$da[2],(int)$da[3],(int)$da[1]);
1443         } else {
1444                 # Bogus value; fall back to the epoch...
1445                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1446                 $uts = 0;
1447         }
1448
1449
1450         switch($outputtype) {
1451                 case TS_UNIX:
1452                         return $uts;
1453                 case TS_MW:
1454                         return gmdate( 'YmdHis', $uts );
1455                 case TS_DB:
1456                         return gmdate( 'Y-m-d H:i:s', $uts );
1457                 case TS_ISO_8601:
1458                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1459                 // This shouldn't ever be used, but is included for completeness
1460                 case TS_EXIF:
1461                         return gmdate(  'Y:m:d H:i:s', $uts );
1462                 case TS_RFC2822:
1463                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1464                 case TS_ORACLE:
1465                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1466                 case TS_POSTGRES:
1467                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1468                 default:
1469                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1470         }
1471 }
1472
1473 /**
1474  * Return a formatted timestamp, or null if input is null.
1475  * For dealing with nullable timestamp columns in the database.
1476  * @param int $outputtype
1477  * @param string $ts
1478  * @return string
1479  */
1480 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1481         if( is_null( $ts ) ) {
1482                 return null;
1483         } else {
1484                 return wfTimestamp( $outputtype, $ts );
1485         }
1486 }
1487
1488 /**
1489  * Check if the operating system is Windows
1490  *
1491  * @return bool True if it's Windows, False otherwise.
1492  */
1493 function wfIsWindows() {
1494         if (substr(php_uname(), 0, 7) == 'Windows') {
1495                 return true;
1496         } else {
1497                 return false;
1498         }
1499 }
1500
1501 /**
1502  * Swap two variables
1503  */
1504 function swap( &$x, &$y ) {
1505         $z = $x;
1506         $x = $y;
1507         $y = $z;
1508 }
1509
1510 function wfGetCachedNotice( $name ) {
1511         global $wgOut, $parserMemc;
1512         $fname = 'wfGetCachedNotice';
1513         wfProfileIn( $fname );
1514
1515         $needParse = false;
1516
1517         if( $name === 'default' ) {
1518                 // special case
1519                 global $wgSiteNotice;
1520                 $notice = $wgSiteNotice;
1521                 if( empty( $notice ) ) {
1522                         wfProfileOut( $fname );
1523                         return false;
1524                 }
1525         } else {
1526                 $notice = wfMsgForContentNoTrans( $name );
1527                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1528                         wfProfileOut( $fname );
1529                         return( false );
1530                 }
1531         }
1532
1533         $cachedNotice = $parserMemc->get( wfMemcKey( $name ) );
1534         if( is_array( $cachedNotice ) ) {
1535                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1536                         $notice = $cachedNotice['html'];
1537                 } else {
1538                         $needParse = true;
1539                 }
1540         } else {
1541                 $needParse = true;
1542         }
1543
1544         if( $needParse ) {
1545                 if( is_object( $wgOut ) ) {
1546                         $parsed = $wgOut->parse( $notice );
1547                         $parserMemc->set( wfMemcKey( $name ), array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1548                         $notice = $parsed;
1549                 } else {
1550                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1551                         $notice = '';
1552                 }
1553         }
1554
1555         wfProfileOut( $fname );
1556         return $notice;
1557 }
1558
1559 function wfGetNamespaceNotice() {
1560         global $wgTitle;
1561
1562         # Paranoia
1563         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1564                 return "";
1565
1566         $fname = 'wfGetNamespaceNotice';
1567         wfProfileIn( $fname );
1568
1569         $key = "namespacenotice-" . $wgTitle->getNsText();
1570         $namespaceNotice = wfGetCachedNotice( $key );
1571         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1572                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1573         } else {
1574                 $namespaceNotice = "";
1575         }
1576
1577         wfProfileOut( $fname );
1578         return $namespaceNotice;
1579 }
1580
1581 function wfGetSiteNotice() {
1582         global $wgUser, $wgSiteNotice;
1583         $fname = 'wfGetSiteNotice';
1584         wfProfileIn( $fname );
1585         $siteNotice = '';
1586
1587         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1588                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1589                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1590                 } else {
1591                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1592                         if( !$anonNotice ) {
1593                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1594                         } else {
1595                                 $siteNotice = $anonNotice;
1596                         }
1597                 }
1598                 if( !$siteNotice ) {
1599                         $siteNotice = wfGetCachedNotice( 'default' );
1600                 }
1601         }
1602
1603         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1604         wfProfileOut( $fname );
1605         return $siteNotice;
1606 }
1607
1608 /**
1609  * BC wrapper for MimeMagic::singleton()
1610  * @deprecated
1611  */
1612 function &wfGetMimeMagic() {
1613         return MimeMagic::singleton();
1614 }
1615
1616 /**
1617  * Tries to get the system directory for temporary files.
1618  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1619  * and if none are set /tmp is returned as the generic Unix default.
1620  *
1621  * NOTE: When possible, use the tempfile() function to create temporary
1622  * files to avoid race conditions on file creation, etc.
1623  *
1624  * @return string
1625  */
1626 function wfTempDir() {
1627         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1628                 $tmp = getenv( $var );
1629                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1630                         return $tmp;
1631                 }
1632         }
1633         # Hope this is Unix of some kind!
1634         return '/tmp';
1635 }
1636
1637 /**
1638  * Make directory, and make all parent directories if they don't exist
1639  */
1640 function wfMkdirParents( $fullDir, $mode = 0777 ) {
1641         if ( strval( $fullDir ) === '' ) {
1642                 return true;
1643         }
1644
1645         # Go back through the paths to find the first directory that exists
1646         $currentDir = $fullDir;
1647         $createList = array();
1648         while ( strval( $currentDir ) !== '' && !file_exists( $currentDir ) ) {
1649                 # Strip trailing slashes
1650                 $currentDir = rtrim( $currentDir, '/\\' );
1651
1652                 # Add to create list
1653                 $createList[] = $currentDir;
1654
1655                 # Find next delimiter searching from the end
1656                 $p = max( strrpos( $currentDir, '/' ), strrpos( $currentDir, '\\' ) );
1657                 if ( $p === false ) {
1658                         $currentDir = false;
1659                 } else {
1660                         $currentDir = substr( $currentDir, 0, $p );
1661                 }
1662         }
1663
1664         if ( count( $createList ) == 0 ) {
1665                 # Directory specified already exists
1666                 return true;
1667         } elseif ( $currentDir === false ) {
1668                 # Went all the way back to root and it apparently doesn't exist
1669                 return false;
1670         }
1671
1672         # Now go forward creating directories
1673         $createList = array_reverse( $createList );
1674         foreach ( $createList as $dir ) {
1675                 # use chmod to override the umask, as suggested by the PHP manual
1676                 if ( !mkdir( $dir, $mode ) || !chmod( $dir, $mode ) ) {
1677                         wfDebugLog( 'mkdir', "Unable to create directory $dir\n" );
1678                         return false;
1679                 }
1680         }
1681         return true;
1682 }
1683
1684 /**
1685  * Increment a statistics counter
1686  */
1687  function wfIncrStats( $key ) {
1688          global $wgMemc;
1689          $key = wfMemcKey( 'stats', $key );
1690          if ( is_null( $wgMemc->incr( $key ) ) ) {
1691                  $wgMemc->add( $key, 1 );
1692          }
1693  }
1694
1695 /**
1696  * @param mixed $nr The number to format
1697  * @param int $acc The number of digits after the decimal point, default 2
1698  * @param bool $round Whether or not to round the value, default true
1699  * @return float
1700  */
1701 function wfPercent( $nr, $acc = 2, $round = true ) {
1702         $ret = sprintf( "%.${acc}f", $nr );
1703         return $round ? round( $ret, $acc ) . '%' : "$ret%";
1704 }
1705
1706 /**
1707  * Encrypt a username/password.
1708  *
1709  * @param string $userid ID of the user
1710  * @param string $password Password of the user
1711  * @return string Hashed password
1712  */
1713 function wfEncryptPassword( $userid, $password ) {
1714         global $wgPasswordSalt;
1715         $p = md5( $password);
1716
1717         if($wgPasswordSalt)
1718                 return md5( "{$userid}-{$p}" );
1719         else
1720                 return $p;
1721 }
1722
1723 /**
1724  * Appends to second array if $value differs from that in $default
1725  */
1726 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
1727         if ( is_null( $changed ) ) {
1728                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
1729         }
1730         if ( $default[$key] !== $value ) {
1731                 $changed[$key] = $value;
1732         }
1733 }
1734
1735 /**
1736  * Since wfMsg() and co suck, they don't return false if the message key they
1737  * looked up didn't exist but a XHTML string, this function checks for the
1738  * nonexistance of messages by looking at wfMsg() output
1739  *
1740  * @param $msg      The message key looked up
1741  * @param $wfMsgOut The output of wfMsg*()
1742  * @return bool
1743  */
1744 function wfEmptyMsg( $msg, $wfMsgOut ) {
1745         return $wfMsgOut === "&lt;$msg&gt;";
1746 }
1747
1748 /**
1749  * Find out whether or not a mixed variable exists in a string
1750  *
1751  * @param mixed  needle
1752  * @param string haystack
1753  * @return bool
1754  */
1755 function in_string( $needle, $str ) {
1756         return strpos( $str, $needle ) !== false;
1757 }
1758
1759 function wfSpecialList( $page, $details ) {
1760         global $wgContLang;
1761         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
1762         return $page . $details;
1763 }
1764
1765 /**
1766  * Returns a regular expression of url protocols
1767  *
1768  * @return string
1769  */
1770 function wfUrlProtocols() {
1771         global $wgUrlProtocols;
1772
1773         // Support old-style $wgUrlProtocols strings, for backwards compatibility
1774         // with LocalSettings files from 1.5
1775         if ( is_array( $wgUrlProtocols ) ) {
1776                 $protocols = array();
1777                 foreach ($wgUrlProtocols as $protocol)
1778                         $protocols[] = preg_quote( $protocol, '/' );
1779
1780                 return implode( '|', $protocols );
1781         } else {
1782                 return $wgUrlProtocols;
1783         }
1784 }
1785
1786 /**
1787  * Execute a shell command, with time and memory limits mirrored from the PHP
1788  * configuration if supported.
1789  * @param $cmd Command line, properly escaped for shell.
1790  * @param &$retval optional, will receive the program's exit code.
1791  *                 (non-zero is usually failure)
1792  * @return collected stdout as a string (trailing newlines stripped)
1793  */
1794 function wfShellExec( $cmd, &$retval=null ) {
1795         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
1796
1797         if( ini_get( 'safe_mode' ) ) {
1798                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
1799                 $retval = 1;
1800                 return "Unable to run external programs in safe mode.";
1801         }
1802
1803         if ( php_uname( 's' ) == 'Linux' ) {
1804                 $time = ini_get( 'max_execution_time' );
1805                 $mem = intval( $wgMaxShellMemory );
1806                 $filesize = intval( $wgMaxShellFileSize );
1807
1808                 if ( $time > 0 && $mem > 0 ) {
1809                         $script = "$IP/bin/ulimit-tvf.sh";
1810                         if ( is_executable( $script ) ) {
1811                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize $cmd";
1812                         }
1813                 }
1814         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
1815                 # This is a hack to work around PHP's flawed invocation of cmd.exe
1816                 # http://news.php.net/php.internals/21796
1817                 $cmd = '"' . $cmd . '"';
1818         }
1819         wfDebug( "wfShellExec: $cmd\n" );
1820
1821         $output = array();
1822         $retval = 1; // error by default?
1823         exec( $cmd, $output, $retval ); // returns the last line of output.
1824         return implode( "\n", $output );
1825
1826 }
1827
1828 /**
1829  * This function works like "use VERSION" in Perl, the program will die with a
1830  * backtrace if the current version of PHP is less than the version provided
1831  *
1832  * This is useful for extensions which due to their nature are not kept in sync
1833  * with releases, and might depend on other versions of PHP than the main code
1834  *
1835  * Note: PHP might die due to parsing errors in some cases before it ever
1836  *       manages to call this function, such is life
1837  *
1838  * @see perldoc -f use
1839  *
1840  * @param mixed $version The version to check, can be a string, an integer, or
1841  *                       a float
1842  */
1843 function wfUsePHP( $req_ver ) {
1844         $php_ver = PHP_VERSION;
1845
1846         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
1847                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
1848 }
1849
1850 /**
1851  * This function works like "use VERSION" in Perl except it checks the version
1852  * of MediaWiki, the program will die with a backtrace if the current version
1853  * of MediaWiki is less than the version provided.
1854  *
1855  * This is useful for extensions which due to their nature are not kept in sync
1856  * with releases
1857  *
1858  * @see perldoc -f use
1859  *
1860  * @param mixed $version The version to check, can be a string, an integer, or
1861  *                       a float
1862  */
1863 function wfUseMW( $req_ver ) {
1864         global $wgVersion;
1865
1866         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
1867                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
1868 }
1869
1870 /**
1871  * @deprecated use StringUtils::escapeRegexReplacement
1872  */
1873 function wfRegexReplacement( $string ) {
1874         return StringUtils::escapeRegexReplacement( $string );
1875 }
1876
1877 /**
1878  * Return the final portion of a pathname.
1879  * Reimplemented because PHP5's basename() is buggy with multibyte text.
1880  * http://bugs.php.net/bug.php?id=33898
1881  *
1882  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
1883  * We'll consider it so always, as we don't want \s in our Unix paths either.
1884  *
1885  * @param string $path
1886  * @return string
1887  */
1888 function wfBaseName( $path ) {
1889         $matches = array();
1890         if( preg_match( '#([^/\\\\]*)[/\\\\]*$#', $path, $matches ) ) {
1891                 return $matches[1];
1892         } else {
1893                 return '';
1894         }
1895 }
1896
1897 /**
1898  * Generate a relative path name to the given file.
1899  * May explode on non-matching case-insensitive paths,
1900  * funky symlinks, etc.
1901  *
1902  * @param string $path Absolute destination path including target filename
1903  * @param string $from Absolute source path, directory only
1904  * @return string
1905  */
1906 function wfRelativePath( $path, $from ) {
1907         // Normalize mixed input on Windows...
1908         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
1909         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
1910
1911         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
1912         $against = explode( DIRECTORY_SEPARATOR, $from );
1913
1914         // Trim off common prefix
1915         while( count( $pieces ) && count( $against )
1916                 && $pieces[0] == $against[0] ) {
1917                 array_shift( $pieces );
1918                 array_shift( $against );
1919         }
1920
1921         // relative dots to bump us to the parent
1922         while( count( $against ) ) {
1923                 array_unshift( $pieces, '..' );
1924                 array_shift( $against );
1925         }
1926
1927         array_push( $pieces, wfBaseName( $path ) );
1928
1929         return implode( DIRECTORY_SEPARATOR, $pieces );
1930 }
1931
1932 /**
1933  * Make a URL index, appropriate for the el_index field of externallinks.
1934  */
1935 function wfMakeUrlIndex( $url ) {
1936         wfSuppressWarnings();
1937         $bits = parse_url( $url );
1938         $prots = array( 'http', 'https', 'ftp', 'irc', 'news' );
1939         wfRestoreWarnings();
1940         if ( !$bits || !in_array( $bits['scheme'], $prots ) ) {
1941                 return false;
1942         }
1943         // Reverse the labels in the hostname, convert to lower case
1944         $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
1945         // Add an extra dot to the end
1946         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
1947                 $reversedHost .= '.';
1948         }
1949         // Reconstruct the pseudo-URL
1950         $prot = $bits['scheme'];
1951         $index = "$prot://$reversedHost";
1952         // Leave out user and password. Add the port, path, query and fragment
1953         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
1954         if ( isset( $bits['path'] ) ) {
1955                 $index .= $bits['path'];
1956         } else {
1957                 $index .= '/';
1958         }
1959         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
1960         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
1961         return $index;
1962 }
1963
1964 /**
1965  * Do any deferred updates and clear the list
1966  * TODO: This could be in Wiki.php if that class made any sense at all
1967  */
1968 function wfDoUpdates()
1969 {
1970         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
1971         foreach ( $wgDeferredUpdateList as $update ) {
1972                 $update->doUpdate();
1973         }
1974         foreach ( $wgPostCommitUpdateList as $update ) {
1975                 $update->doUpdate();
1976         }
1977         $wgDeferredUpdateList = array();
1978         $wgPostCommitUpdateList = array();
1979 }
1980
1981 /**
1982  * @deprecated use StringUtils::explodeMarkup
1983  */
1984 function wfExplodeMarkup( $separator, $text ) {
1985         return StringUtils::explodeMarkup( $separator, $text );
1986 }
1987
1988 /**
1989  * Convert an arbitrarily-long digit string from one numeric base
1990  * to another, optionally zero-padding to a minimum column width.
1991  *
1992  * Supports base 2 through 36; digit values 10-36 are represented
1993  * as lowercase letters a-z. Input is case-insensitive.
1994  *
1995  * @param $input string of digits
1996  * @param $sourceBase int 2-36
1997  * @param $destBase int 2-36
1998  * @param $pad int 1 or greater
1999  * @return string or false on invalid input
2000  */
2001 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2002         $input = strval( $input );
2003         if( $sourceBase < 2 ||
2004                 $sourceBase > 36 ||
2005                 $destBase < 2 ||
2006                 $destBase > 36 ||
2007                 $pad < 1 ||
2008                 $sourceBase != intval( $sourceBase ) ||
2009                 $destBase != intval( $destBase ) ||
2010                 $pad != intval( $pad ) ||
2011                 !is_string( $input ) ||
2012                 $input == '' ) {
2013                 return false;
2014         }
2015         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2016         $inDigits = array();
2017         $outChars = '';
2018
2019         // Decode and validate input string
2020         $input = strtolower( $input );
2021         for( $i = 0; $i < strlen( $input ); $i++ ) {
2022                 $n = strpos( $digitChars, $input{$i} );
2023                 if( $n === false || $n > $sourceBase ) {
2024                         return false;
2025                 }
2026                 $inDigits[] = $n;
2027         }
2028
2029         // Iterate over the input, modulo-ing out an output digit
2030         // at a time until input is gone.
2031         while( count( $inDigits ) ) {
2032                 $work = 0;
2033                 $workDigits = array();
2034
2035                 // Long division...
2036                 foreach( $inDigits as $digit ) {
2037                         $work *= $sourceBase;
2038                         $work += $digit;
2039
2040                         if( $work < $destBase ) {
2041                                 // Gonna need to pull another digit.
2042                                 if( count( $workDigits ) ) {
2043                                         // Avoid zero-padding; this lets us find
2044                                         // the end of the input very easily when
2045                                         // length drops to zero.
2046                                         $workDigits[] = 0;
2047                                 }
2048                         } else {
2049                                 // Finally! Actual division!
2050                                 $workDigits[] = intval( $work / $destBase );
2051
2052                                 // Isn't it annoying that most programming languages
2053                                 // don't have a single divide-and-remainder operator,
2054                                 // even though the CPU implements it that way?
2055                                 $work = $work % $destBase;
2056                         }
2057                 }
2058
2059                 // All that division leaves us with a remainder,
2060                 // which is conveniently our next output digit.
2061                 $outChars .= $digitChars[$work];
2062
2063                 // And we continue!
2064                 $inDigits = $workDigits;
2065         }
2066
2067         while( strlen( $outChars ) < $pad ) {
2068                 $outChars .= '0';
2069         }
2070
2071         return strrev( $outChars );
2072 }
2073
2074 /**
2075  * Create an object with a given name and an array of construct parameters
2076  * @param string $name
2077  * @param array $p parameters
2078  */
2079 function wfCreateObject( $name, $p ){
2080         $p = array_values( $p );
2081         switch ( count( $p ) ) {
2082                 case 0:
2083                         return new $name;
2084                 case 1:
2085                         return new $name( $p[0] );
2086                 case 2:
2087                         return new $name( $p[0], $p[1] );
2088                 case 3:
2089                         return new $name( $p[0], $p[1], $p[2] );
2090                 case 4:
2091                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2092                 case 5:
2093                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2094                 case 6:
2095                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2096                 default:
2097                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2098         }
2099 }
2100
2101 /**
2102  * Aliases for modularized functions
2103  */
2104 function wfGetHTTP( $url, $timeout = 'default' ) {
2105         return Http::get( $url, $timeout );
2106 }
2107 function wfIsLocalURL( $url ) {
2108         return Http::isLocalURL( $url );
2109 }
2110
2111 /**
2112  * Initialise php session
2113  */
2114 function wfSetupSession() {
2115         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure;
2116         if( $wgSessionsInMemcached ) {
2117                 require_once( 'MemcachedSessions.php' );
2118         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2119                 # If it's left on 'user' or another setting from another
2120                 # application, it will end up failing. Try to recover.
2121                 ini_set ( 'session.save_handler', 'files' );
2122         }
2123         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure);
2124         session_cache_limiter( 'private, must-revalidate' );
2125         @session_start();
2126 }
2127
2128 /**
2129  * Get an object from the precompiled serialized directory
2130  *
2131  * @return mixed The variable on success, false on failure
2132  */
2133 function wfGetPrecompiledData( $name ) {
2134         global $IP;
2135
2136         $file = "$IP/serialized/$name";
2137         if ( file_exists( $file ) ) {
2138                 $blob = file_get_contents( $file );
2139                 if ( $blob ) {
2140                         return unserialize( $blob );
2141                 }
2142         }
2143         return false;
2144 }
2145
2146 function wfGetCaller( $level = 2 ) {
2147         $backtrace = wfDebugBacktrace();
2148         if ( isset( $backtrace[$level] ) ) {
2149                 if ( isset( $backtrace[$level]['class'] ) ) {
2150                         $caller = $backtrace[$level]['class'] . '::' . $backtrace[$level]['function'];
2151                 } else {
2152                         $caller = $backtrace[$level]['function'];
2153                 }
2154         } else {
2155                 $caller = 'unknown';
2156         }
2157         return $caller;
2158 }
2159
2160 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2161 function wfGetAllCallers() {
2162         return implode('/', array_map(
2163                 create_function('$frame','
2164                         return isset( $frame["class"] )?
2165                                 $frame["class"]."::".$frame["function"]:
2166                                 $frame["function"];
2167                         '),
2168                 array_reverse(wfDebugBacktrace())));
2169 }
2170
2171 /**
2172  * Get a cache key
2173  */
2174 function wfMemcKey( /*... */ ) {
2175         global $wgDBprefix, $wgDBname;
2176         $args = func_get_args();
2177         if ( $wgDBprefix ) {
2178                 $key = "$wgDBname-$wgDBprefix:" . implode( ':', $args );
2179         } else {
2180                 $key = $wgDBname . ':' . implode( ':', $args );
2181         }
2182         return $key;
2183 }
2184
2185 /**
2186  * Get a cache key for a foreign DB
2187  */
2188 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2189         $args = array_slice( func_get_args(), 2 );
2190         if ( $prefix ) {
2191                 $key = "$db-$prefix:" . implode( ':', $args );
2192         } else {
2193                 $key = $db . ':' . implode( ':', $args );
2194         }
2195         return $key;
2196 }
2197
2198 /**
2199  * Get an ASCII string identifying this wiki
2200  * This is used as a prefix in memcached keys
2201  */
2202 function wfWikiID() {
2203         global $wgDBprefix, $wgDBname;
2204         if ( $wgDBprefix ) {
2205                 return "$wgDBname-$wgDBprefix";
2206         } else {
2207                 return $wgDBname;
2208         }
2209 }
2210
2211 /*
2212  * Get a Database object
2213  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2214  *                master (for write queries), DB_SLAVE for potentially lagged
2215  *                read queries, or an integer >= 0 for a particular server.
2216  *
2217  * @param mixed $groups Query groups. An array of group names that this query
2218  *              belongs to. May contain a single string if the query is only
2219  *              in one group.
2220  */
2221 function &wfGetDB( $db = DB_LAST, $groups = array() ) {
2222         global $wgLoadBalancer;
2223         $ret = $wgLoadBalancer->getConnection( $db, true, $groups );
2224         return $ret;
2225 }
2226 ?>