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