includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 require_once dirname( __FILE__ ) . '/normal/UtfNormalUtil.php';
  12
  13 // Hide compatibility functions from Doxygen
  14 /// @cond
  15
  16 /**
  17  * Compatibility functions
  18  *
  19  * We support PHP 5.1.x and up.
  20  * Re-implementations of newer functions or functions in non-standard
  21  * PHP extensions may be included here.
  22  */
  23
  24 if( !function_exists( 'iconv' ) ) {
  25         function iconv( $from, $to, $string ) {
  26                 return Fallback::fallback_iconv( $from, $to, $string );
  27         }
  28 }
  29
  30 if ( !function_exists( 'mb_substr' ) ) {
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::fallback_mb_substr( $str, $start, $count );
  33         }
  34
  35         function mb_substr_split_unicode( $str, $splitPos ) {
  36                 return Fallback::fallback_mb_substr_split_unicode( $str, $splitPos );
  37         }
  38 }
  39
  40 if ( !function_exists( 'mb_strlen' ) ) {
  41         function mb_strlen( $str, $enc = '' ) {
  42                 return Fallback::fallback_mb_strlen( $str, $enc );
  43         }
  44 }
  45
  46 if( !function_exists( 'mb_strpos' ) ) {
  47
  48         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  49                 return Fallback::fallback_mb_strpos( $haystack, $needle, $offset, $encoding );
  50         }
  51
  52 }
  53
  54 if( !function_exists( 'mb_strrpos' ) ) {
  55         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  56                 return Fallback::fallback_mb_strrpos( $haystack, $needle, $offset, $encoding );
  57         }
  58 }
  59
  60
  61 // Support for Wietse Venema's taint feature
  62 if ( !function_exists( 'istainted' ) ) {
  63         function istainted( $var ) {
  64                 return 0;
  65         }
  66         function taint( $var, $level = 0 ) {}
  67         function untaint( $var, $level = 0 ) {}
  68         define( 'TC_HTML', 1 );
  69         define( 'TC_SHELL', 1 );
  70         define( 'TC_MYSQL', 1 );
  71         define( 'TC_PCRE', 1 );
  72         define( 'TC_SELF', 1 );
  73 }
  74 /// @endcond
  75
  76
  77
  78 /**
  79  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  80  */
  81 function wfArrayDiff2( $a, $b ) {
  82         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  83 }
  84 function wfArrayDiff2_cmp( $a, $b ) {
  85         if ( !is_array( $a ) ) {
  86                 return strcmp( $a, $b );
  87         } elseif ( count( $a ) !== count( $b ) ) {
  88                 return count( $a ) < count( $b ) ? -1 : 1;
  89         } else {
  90                 reset( $a );
  91                 reset( $b );
  92                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
  93                         $cmp = strcmp( $valueA, $valueB );
  94                         if ( $cmp !== 0 ) {
  95                                 return $cmp;
  96                         }
  97                 }
  98                 return 0;
  99         }
 100 }
 101
 102 /**
 103  * Get a random decimal value between 0 and 1, in a way
 104  * not likely to give duplicate values for any realistic
 105  * number of articles.
 106  *
 107  * @return string
 108  */
 109 function wfRandom() {
 110         # The maximum random value is "only" 2^31-1, so get two random
 111         # values to reduce the chance of dupes
 112         $max = mt_getrandmax() + 1;
 113         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 114                 / $max / $max, 12, '.', '' );
 115         return $rand;
 116 }
 117
 118 /**
 119  * We want some things to be included as literal characters in our title URLs
 120  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 121  * all of the following should be safe:
 122  *
 123  * ;:@&=$-_.+!*'(),
 124  *
 125  * But + is not safe because it's used to indicate a space; &= are only safe in
 126  * paths and not in queries (and we don't distinguish here); ' seems kind of
 127  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 128  * is reserved, we don't care.  So the list we unescape is:
 129  *
 130  * ;:@$!*(),/
 131  *
 132  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 133  * so no fancy : for IIS7.
 134  *
 135  * %2F in the page titles seems to fatally break for some reason.
 136  *
 137  * @param $s String:
 138  * @return string
 139 */
 140 function wfUrlencode( $s ) {
 141         static $needle;
 142         if ( is_null( $needle ) ) {
 143                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 144                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 145                         $needle[] = '%3A';
 146                 }
 147         }
 148
 149         $s = urlencode( $s );
 150         $s = str_ireplace(
 151                 $needle,
 152                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 153                 $s
 154         );
 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         global $wgDebugLogPrefix, $wgShowDebug;
 175
 176         static $cache = array(); // Cache of unoutputted messages
 177         $text = wfDebugTimer() . $text;
 178
 179         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 180         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 181                 return;
 182         }
 183
 184         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 185                 $cache[] = $text;
 186
 187                 if ( isset( $wgOut ) && StubObject::isRealObject( $wgOut ) ) {
 188                         // add the message and any cached messages to the output
 189                         array_map( array( $wgOut, 'debug' ), $cache );
 190                         $cache = array();
 191                 }
 192         }
 193         if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 194                 # Strip unprintables; they can switch terminal modes when binary data
 195                 # gets dumped, which is pretty annoying.
 196                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 197                 $text = $wgDebugLogPrefix . $text;
 198                 wfErrorLog( $text, $wgDebugLogFile );
 199         }
 200 }
 201
 202 function wfDebugTimer() {
 203         global $wgDebugTimestamps;
 204         if ( !$wgDebugTimestamps ) {
 205                 return '';
 206         }
 207         static $start = null;
 208
 209         if ( $start === null ) {
 210                 $start = microtime( true );
 211                 $prefix = "\n$start";
 212         } else {
 213                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 214         }
 215
 216         return $prefix . '  ';
 217 }
 218
 219 /**
 220  * Send a line giving PHP memory usage.
 221  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 222  */
 223 function wfDebugMem( $exact = false ) {
 224         $mem = memory_get_usage();
 225         if( !$exact ) {
 226                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 227         } else {
 228                 $mem .= ' bytes';
 229         }
 230         wfDebug( "Memory usage: $mem\n" );
 231 }
 232
 233 /**
 234  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 235  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 236  *
 237  * @param $logGroup String
 238  * @param $text String
 239  * @param $public Bool: whether to log the event in the public log if no private
 240  *                     log file is specified, (default true)
 241  */
 242 function wfDebugLog( $logGroup, $text, $public = true ) {
 243         global $wgDebugLogGroups, $wgShowHostnames;
 244         $text = trim( $text ) . "\n";
 245         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 246                 $time = wfTimestamp( TS_DB );
 247                 $wiki = wfWikiID();
 248                 if ( $wgShowHostnames ) {
 249                         $host = wfHostname();
 250                 } else {
 251                         $host = '';
 252                 }
 253                 wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 254         } elseif ( $public === true ) {
 255                 wfDebug( $text, true );
 256         }
 257 }
 258
 259 /**
 260  * Log for database errors
 261  * @param $text String: database error message.
 262  */
 263 function wfLogDBError( $text ) {
 264         global $wgDBerrorLog, $wgDBname;
 265         if ( $wgDBerrorLog ) {
 266                 $host = trim(`hostname`);
 267                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 268                 wfErrorLog( $text, $wgDBerrorLog );
 269         }
 270 }
 271
 272 /**
 273  * Log to a file without getting "file size exceeded" signals.
 274  *
 275  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 276  * send lines to the specified port, prefixed by the specified prefix and a space.
 277  */
 278 function wfErrorLog( $text, $file ) {
 279         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 280                 # Needs the sockets extension
 281                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 282                         // IPv6 bracketed host
 283                         $host = $m[2];
 284                         $port = intval( $m[3] );
 285                         $prefix = isset( $m[4] ) ? $m[4] : false;
 286                         $domain = AF_INET6;
 287                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 288                         $host = $m[2];
 289                         if ( !IP::isIPv4( $host ) ) {
 290                                 $host = gethostbyname( $host );
 291                         }
 292                         $port = intval( $m[3] );
 293                         $prefix = isset( $m[4] ) ? $m[4] : false;
 294                         $domain = AF_INET;
 295                 } else {
 296                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 297                 }
 298                 // Clean it up for the multiplexer
 299                 if ( strval( $prefix ) !== '' ) {
 300                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 301                         if ( substr( $text, -1 ) != "\n" ) {
 302                                 $text .= "\n";
 303                         }
 304                 }
 305
 306                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 307                 if ( !$sock ) {
 308                         return;
 309                 }
 310                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 311                 socket_close( $sock );
 312         } else {
 313                 wfSuppressWarnings();
 314                 $exists = file_exists( $file );
 315                 $size = $exists ? filesize( $file ) : false;
 316                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 317                         error_log( $text, 3, $file );
 318                 }
 319                 wfRestoreWarnings();
 320         }
 321 }
 322
 323 /**
 324  * @todo document
 325  */
 326 function wfLogProfilingData() {
 327         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 328         global $wgProfiler, $wgProfileLimit, $wgUser;
 329         # Profiling must actually be enabled...
 330         if( is_null( $wgProfiler ) ) {
 331                 return;
 332         }
 333         # Get total page request time
 334         $now = wfTime();
 335         $elapsed = $now - $wgRequestTime;
 336         # Only show pages that longer than $wgProfileLimit time (default is 0)
 337         if( $elapsed <= $wgProfileLimit ) {
 338                 return;
 339         }
 340         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 341         $forward = '';
 342         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 343                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 344         }
 345         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 346                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 347         }
 348         if( !empty( $_SERVER['HTTP_FROM'] ) ) {
 349                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 350         }
 351         if( $forward ) {
 352                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 353         }
 354         // Don't unstub $wgUser at this late stage just for statistics purposes
 355         // FIXME: We can detect some anons even if it is not loaded. See User::getId()
 356         if( $wgUser->mDataLoaded && $wgUser->isAnon() ) {
 357                 $forward .= ' anon';
 358         }
 359         $log = sprintf( "%s\t%04.3f\t%s\n",
 360                 gmdate( 'YmdHis' ), $elapsed,
 361                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 362         if ( $wgDebugLogFile != '' && ( $wgRequest->getVal( 'action' ) != 'raw' || $wgDebugRawPage ) ) {
 363                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 364         }
 365 }
 366
 367 /**
 368  * Check if the wiki read-only lock file is present. This can be used to lock
 369  * off editing functions, but doesn't guarantee that the database will not be
 370  * modified.
 371  * @return bool
 372  */
 373 function wfReadOnly() {
 374         global $wgReadOnlyFile, $wgReadOnly;
 375
 376         if ( !is_null( $wgReadOnly ) ) {
 377                 return (bool)$wgReadOnly;
 378         }
 379         if ( $wgReadOnlyFile == '' ) {
 380                 return false;
 381         }
 382         // Set $wgReadOnly for faster access next time
 383         if ( is_file( $wgReadOnlyFile ) ) {
 384                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 385         } else {
 386                 $wgReadOnly = false;
 387         }
 388         return (bool)$wgReadOnly;
 389 }
 390
 391 function wfReadOnlyReason() {
 392         global $wgReadOnly;
 393         wfReadOnly();
 394         return $wgReadOnly;
 395 }
 396
 397 /**
 398  * Return a Language object from $langcode
 399  * @param $langcode Mixed: either:
 400  *                  - a Language object
 401  *                  - code of the language to get the message for, if it is
 402  *                    a valid code create a language for that language, if
 403  *                    it is a string but not a valid code then make a basic
 404  *                    language object
 405  *                  - a boolean: if it's false then use the current users
 406  *                    language (as a fallback for the old parameter
 407  *                    functionality), or if it is true then use the wikis
 408  * @return Language object
 409  */
 410 function wfGetLangObj( $langcode = false ) {
 411         # Identify which language to get or create a language object for.
 412         # Using is_object here due to Stub objects.
 413         if( is_object( $langcode ) ) {
 414                 # Great, we already have the object (hopefully)!
 415                 return $langcode;
 416         }
 417
 418         global $wgContLang, $wgLanguageCode;
 419         if( $langcode === true || $langcode === $wgLanguageCode ) {
 420                 # $langcode is the language code of the wikis content language object.
 421                 # or it is a boolean and value is true
 422                 return $wgContLang;
 423         }
 424
 425         global $wgLang;
 426         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 427                 # $langcode is the language code of user language object.
 428                 # or it was a boolean and value is false
 429                 return $wgLang;
 430         }
 431
 432         $validCodes = array_keys( Language::getLanguageNames() );
 433         if( in_array( $langcode, $validCodes ) ) {
 434                 # $langcode corresponds to a valid language.
 435                 return Language::factory( $langcode );
 436         }
 437
 438         # $langcode is a string, but not a valid language code; use content language.
 439         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 440         return $wgContLang;
 441 }
 442
 443 /**
 444  * Use this instead of $wgContLang, when working with user interface.
 445  * User interface is currently hard coded according to wiki content language
 446  * in many ways, especially regarding to text direction. There is lots stuff
 447  * to fix, hence this function to keep the old behaviour unless the global
 448  * $wgBetterDirectionality is enabled (or removed when everything works).
 449  */
 450 function wfUILang() {
 451         global $wgBetterDirectionality;
 452         return wfGetLangObj( !$wgBetterDirectionality );
 453 }
 454
 455 /**
 456  * This is the new function for getting translated interface messages.
 457  * See the Message class for documentation how to use them.
 458  * The intention is that this function replaces all old wfMsg* functions.
 459  * @param $key \string Message key.
 460  * Varargs: normal message parameters.
 461  * @return \type{Message}
 462  * @since 1.17
 463  */
 464 function wfMessage( $key /*...*/) {
 465         $params = func_get_args();
 466         array_shift( $params );
 467         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 468                 $params = $params[0];
 469         }
 470         return new Message( $key, $params );
 471 }
 472
 473 /**
 474  * This function accepts multiple message keys and returns a message instance
 475  * for the first message which is non-empty. If all messages are empty then an
 476  * instance of the first message key is returned.
 477  * Varargs: message keys
 478  * @return \type{Message}
 479  * @since 1.18
 480  */
 481 function wfMessageFallback( /*...*/ ) {
 482         $keys = func_get_args();
 483         $first = $keys[0];
 484         foreach ( $keys as $key ) {
 485                 if ( wfEmptyMsg( $key ) ) {
 486                         continue;
 487                 }
 488                 return wfMessage( $key );
 489         }
 490         return wfMessage( $first );
 491 }
 492
 493 /**
 494  * Get a message from anywhere, for the current user language.
 495  *
 496  * Use wfMsgForContent() instead if the message should NOT
 497  * change depending on the user preferences.
 498  *
 499  * @param $key String: lookup key for the message, usually
 500  *    defined in languages/Language.php
 501  *
 502  * This function also takes extra optional parameters (not
 503  * shown in the function definition), which can be used to
 504  * insert variable text into the predefined message.
 505  */
 506 function wfMsg( $key ) {
 507         $args = func_get_args();
 508         array_shift( $args );
 509         return wfMsgReal( $key, $args, true );
 510 }
 511
 512 /**
 513  * Same as above except doesn't transform the message
 514  */
 515 function wfMsgNoTrans( $key ) {
 516         $args = func_get_args();
 517         array_shift( $args );
 518         return wfMsgReal( $key, $args, true, false, false );
 519 }
 520
 521 /**
 522  * Get a message from anywhere, for the current global language
 523  * set with $wgLanguageCode.
 524  *
 525  * Use this if the message should NOT change dependent on the
 526  * language set in the user's preferences. This is the case for
 527  * most text written into logs, as well as link targets (such as
 528  * the name of the copyright policy page). Link titles, on the
 529  * other hand, should be shown in the UI language.
 530  *
 531  * Note that MediaWiki allows users to change the user interface
 532  * language in their preferences, but a single installation
 533  * typically only contains content in one language.
 534  *
 535  * Be wary of this distinction: If you use wfMsg() where you should
 536  * use wfMsgForContent(), a user of the software may have to
 537  * customize potentially hundreds of messages in
 538  * order to, e.g., fix a link in every possible language.
 539  *
 540  * @param $key String: lookup key for the message, usually
 541  *    defined in languages/Language.php
 542  */
 543 function wfMsgForContent( $key ) {
 544         global $wgForceUIMsgAsContentMsg;
 545         $args = func_get_args();
 546         array_shift( $args );
 547         $forcontent = true;
 548         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 549                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 550         {
 551                 $forcontent = false;
 552         }
 553         return wfMsgReal( $key, $args, true, $forcontent );
 554 }
 555
 556 /**
 557  * Same as above except doesn't transform the message
 558  */
 559 function wfMsgForContentNoTrans( $key ) {
 560         global $wgForceUIMsgAsContentMsg;
 561         $args = func_get_args();
 562         array_shift( $args );
 563         $forcontent = true;
 564         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 565                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 566         {
 567                 $forcontent = false;
 568         }
 569         return wfMsgReal( $key, $args, true, $forcontent, false );
 570 }
 571
 572 /**
 573  * Get a message from the language file, for the UI elements
 574  */
 575 function wfMsgNoDB( $key ) {
 576         $args = func_get_args();
 577         array_shift( $args );
 578         return wfMsgReal( $key, $args, false );
 579 }
 580
 581 /**
 582  * Get a message from the language file, for the content
 583  */
 584 function wfMsgNoDBForContent( $key ) {
 585         global $wgForceUIMsgAsContentMsg;
 586         $args = func_get_args();
 587         array_shift( $args );
 588         $forcontent = true;
 589         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 590                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 591         {
 592                 $forcontent = false;
 593         }
 594         return wfMsgReal( $key, $args, false, $forcontent );
 595 }
 596
 597
 598 /**
 599  * Really get a message
 600  * @param $key String: key to get.
 601  * @param $args
 602  * @param $useDB Boolean
 603  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 604  * @param $transform Boolean: Whether or not to transform the message.
 605  * @return String: the requested message.
 606  */
 607 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 608         wfProfileIn( __METHOD__ );
 609         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 610         $message = wfMsgReplaceArgs( $message, $args );
 611         wfProfileOut( __METHOD__ );
 612         return $message;
 613 }
 614
 615 /**
 616  * This function provides the message source for messages to be edited which are *not* stored in the database.
 617  * @param $key String:
 618  */
 619 function wfMsgWeirdKey( $key ) {
 620         $source = wfMsgGetKey( $key, false, true, false );
 621         if ( wfEmptyMsg( $key, $source ) ) {
 622                 return '';
 623         } else {
 624                 return $source;
 625         }
 626 }
 627
 628 /**
 629  * Fetch a message string value, but don't replace any keys yet.
 630  * @param $key String
 631  * @param $useDB Bool
 632  * @param $langCode String: Code of the language to get the message for, or
 633  *                  behaves as a content language switch if it is a boolean.
 634  * @param $transform Boolean: whether to parse magic words, etc.
 635  * @return string
 636  */
 637 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 638         global $wgMessageCache;
 639
 640         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 641
 642         if ( !is_object( $wgMessageCache ) ) {
 643                 throw new MWException( 'Trying to get message before message cache is initialised' );
 644         }
 645
 646         $message = $wgMessageCache->get( $key, $useDB, $langCode );
 647         if( $message === false ) {
 648                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 649         } elseif ( $transform ) {
 650                 $message = $wgMessageCache->transform( $message );
 651         }
 652         return $message;
 653 }
 654
 655 /**
 656  * Replace message parameter keys on the given formatted output.
 657  *
 658  * @param $message String
 659  * @param $args Array
 660  * @return string
 661  * @private
 662  */
 663 function wfMsgReplaceArgs( $message, $args ) {
 664         # Fix windows line-endings
 665         # Some messages are split with explode("\n", $msg)
 666         $message = str_replace( "\r", '', $message );
 667
 668         // Replace arguments
 669         if ( count( $args ) ) {
 670                 if ( is_array( $args[0] ) ) {
 671                         $args = array_values( $args[0] );
 672                 }
 673                 $replacementKeys = array();
 674                 foreach( $args as $n => $param ) {
 675                         $replacementKeys['$' . ( $n + 1 )] = $param;
 676                 }
 677                 $message = strtr( $message, $replacementKeys );
 678         }
 679
 680         return $message;
 681 }
 682
 683 /**
 684  * Return an HTML-escaped version of a message.
 685  * Parameter replacements, if any, are done *after* the HTML-escaping,
 686  * so parameters may contain HTML (eg links or form controls). Be sure
 687  * to pre-escape them if you really do want plaintext, or just wrap
 688  * the whole thing in htmlspecialchars().
 689  *
 690  * @param $key String
 691  * @param string ... parameters
 692  * @return string
 693  */
 694 function wfMsgHtml( $key ) {
 695         $args = func_get_args();
 696         array_shift( $args );
 697         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 698 }
 699
 700 /**
 701  * Return an HTML version of message
 702  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 703  * so parameters may contain HTML (eg links or form controls). Be sure
 704  * to pre-escape them if you really do want plaintext, or just wrap
 705  * the whole thing in htmlspecialchars().
 706  *
 707  * @param $key String
 708  * @param string ... parameters
 709  * @return string
 710  */
 711 function wfMsgWikiHtml( $key ) {
 712         global $wgOut;
 713         $args = func_get_args();
 714         array_shift( $args );
 715         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 716 }
 717
 718 /**
 719  * Returns message in the requested format
 720  * @param $key String: key of the message
 721  * @param $options Array: processing rules. Can take the following options:
 722  *   <i>parse</i>: parses wikitext to HTML
 723  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 724  *       p's added by parser or tidy
 725  *   <i>escape</i>: filters message through htmlspecialchars
 726  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 727  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 728  *   <i>parsemag</i>: transform the message using magic phrases
 729  *   <i>content</i>: fetch message for content language instead of interface
 730  * Also can accept a single associative argument, of the form 'language' => 'xx':
 731  *   <i>language</i>: Language object or language code to fetch message for
 732  *       (overriden by <i>content</i>), its behaviour with parse, parseinline
 733  *       and parsemag is undefined.
 734  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 735  */
 736 function wfMsgExt( $key, $options ) {
 737         global $wgOut;
 738
 739         $args = func_get_args();
 740         array_shift( $args );
 741         array_shift( $args );
 742         $options = (array)$options;
 743
 744         foreach( $options as $arrayKey => $option ) {
 745                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 746                         # An unknown index, neither numeric nor "language"
 747                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 748                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 749                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 750                 'replaceafter', 'parsemag', 'content' ) ) ) {
 751                         # A numeric index with unknown value
 752                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 753                 }
 754         }
 755
 756         if( in_array( 'content', $options, true ) ) {
 757                 $forContent = true;
 758                 $langCode = true;
 759         } elseif( array_key_exists( 'language', $options ) ) {
 760                 $forContent = false;
 761                 $langCode = wfGetLangObj( $options['language'] );
 762         } else {
 763                 $forContent = false;
 764                 $langCode = false;
 765         }
 766
 767         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 768
 769         if( !in_array( 'replaceafter', $options, true ) ) {
 770                 $string = wfMsgReplaceArgs( $string, $args );
 771         }
 772
 773         if( in_array( 'parse', $options, true ) ) {
 774                 $string = $wgOut->parse( $string, true, !$forContent );
 775         } elseif ( in_array( 'parseinline', $options, true ) ) {
 776                 $string = $wgOut->parse( $string, true, !$forContent );
 777                 $m = array();
 778                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 779                         $string = $m[1];
 780                 }
 781         } elseif ( in_array( 'parsemag', $options, true ) ) {
 782                 global $wgMessageCache;
 783                 if ( isset( $wgMessageCache ) ) {
 784                         $string = $wgMessageCache->transform( $string,
 785                                 !$forContent,
 786                                 is_object( $langCode ) ? $langCode : null );
 787                 }
 788         }
 789
 790         if ( in_array( 'escape', $options, true ) ) {
 791                 $string = htmlspecialchars ( $string );
 792         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 793                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 794         }
 795
 796         if( in_array( 'replaceafter', $options, true ) ) {
 797                 $string = wfMsgReplaceArgs( $string, $args );
 798         }
 799
 800         return $string;
 801 }
 802
 803
 804 /**
 805  * Just like exit() but makes a note of it.
 806  * Commits open transactions except if the error parameter is set
 807  *
 808  * @deprecated Please return control to the caller or throw an exception. Will
 809  *             be removed in 1.19.
 810  */
 811 function wfAbruptExit( $error = false ) {
 812         static $called = false;
 813         if ( $called ) {
 814                 exit( -1 );
 815         }
 816         $called = true;
 817
 818         wfDeprecated( __FUNCTION__ );
 819         $bt = wfDebugBacktrace();
 820         if( $bt ) {
 821                 for( $i = 0; $i < count( $bt ); $i++ ) {
 822                         $file = isset( $bt[$i]['file'] ) ? $bt[$i]['file'] : 'unknown';
 823                         $line = isset( $bt[$i]['line'] ) ? $bt[$i]['line'] : 'unknown';
 824                         wfDebug( "WARNING: Abrupt exit in $file at line $line\n");
 825                 }
 826         } else {
 827                 wfDebug( "WARNING: Abrupt exit\n" );
 828         }
 829
 830         wfLogProfilingData();
 831
 832         if ( !$error ) {
 833                 wfGetLB()->closeAll();
 834         }
 835         exit( -1 );
 836 }
 837
 838 /**
 839  * @deprecated Please return control the caller or throw an exception. Will
 840  *             be removed in 1.19.
 841  */
 842 function wfErrorExit() {
 843         wfDeprecated( __FUNCTION__ );
 844         wfAbruptExit( true );
 845 }
 846
 847 /**
 848  * Print a simple message and die, returning nonzero to the shell if any.
 849  * Plain die() fails to return nonzero to the shell if you pass a string.
 850  * @param $msg String
 851  */
 852 function wfDie( $msg = '' ) {
 853         echo $msg;
 854         die( 1 );
 855 }
 856
 857 /**
 858  * Throw a debugging exception. This function previously once exited the process,
 859  * but now throws an exception instead, with similar results.
 860  *
 861  * @param $msg String: message shown when dieing.
 862  */
 863 function wfDebugDieBacktrace( $msg = '' ) {
 864         throw new MWException( $msg );
 865 }
 866
 867 /**
 868  * Fetch server name for use in error reporting etc.
 869  * Use real server name if available, so we know which machine
 870  * in a server farm generated the current page.
 871  * @return string
 872  */
 873 function wfHostname() {
 874         static $host;
 875         if ( is_null( $host ) ) {
 876                 if ( function_exists( 'posix_uname' ) ) {
 877                         // This function not present on Windows
 878                         $uname = @posix_uname();
 879                 } else {
 880                         $uname = false;
 881                 }
 882                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 883                         $host = $uname['nodename'];
 884                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
 885                         # Windows computer name
 886                         $host = getenv( 'COMPUTERNAME' );
 887                 } else {
 888                         # This may be a virtual server.
 889                         $host = $_SERVER['SERVER_NAME'];
 890                 }
 891         }
 892         return $host;
 893 }
 894
 895 /**
 896  * Returns a HTML comment with the elapsed time since request.
 897  * This method has no side effects.
 898  * @return string
 899  */
 900 function wfReportTime() {
 901         global $wgRequestTime, $wgShowHostnames;
 902
 903         $now = wfTime();
 904         $elapsed = $now - $wgRequestTime;
 905
 906         return $wgShowHostnames
 907                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
 908                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
 909 }
 910
 911 /**
 912  * Safety wrapper for debug_backtrace().
 913  *
 914  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 915  * murky circumstances, which may be triggered in part by stub objects
 916  * or other fancy talkin'.
 917  *
 918  * Will return an empty array if Zend Optimizer is detected or if
 919  * debug_backtrace is disabled, otherwise the output from
 920  * debug_backtrace() (trimmed).
 921  *
 922  * @return array of backtrace information
 923  */
 924 function wfDebugBacktrace() {
 925         static $disabled = null;
 926
 927         if( extension_loaded( 'Zend Optimizer' ) ) {
 928                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 929                 return array();
 930         }
 931
 932         if ( is_null( $disabled ) ) {
 933                 $disabled = false;
 934                 $functions = explode( ',', ini_get( 'disable_functions' ) );
 935                 $functions = array_map( 'trim', $functions );
 936                 $functions = array_map( 'strtolower', $functions );
 937                 if ( in_array( 'debug_backtrace', $functions ) ) {
 938                         wfDebug( "debug_backtrace is in disabled_functions\n" );
 939                         $disabled = true;
 940                 }
 941         }
 942         if ( $disabled ) {
 943                 return array();
 944         }
 945
 946         return array_slice( debug_backtrace(), 1 );
 947 }
 948
 949 function wfBacktrace() {
 950         global $wgCommandLineMode;
 951
 952         if ( $wgCommandLineMode ) {
 953                 $msg = '';
 954         } else {
 955                 $msg = "<ul>\n";
 956         }
 957         $backtrace = wfDebugBacktrace();
 958         foreach( $backtrace as $call ) {
 959                 if( isset( $call['file'] ) ) {
 960                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 961                         $file = $f[count( $f ) - 1];
 962                 } else {
 963                         $file = '-';
 964                 }
 965                 if( isset( $call['line'] ) ) {
 966                         $line = $call['line'];
 967                 } else {
 968                         $line = '-';
 969                 }
 970                 if ( $wgCommandLineMode ) {
 971                         $msg .= "$file line $line calls ";
 972                 } else {
 973                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 974                 }
 975                 if( !empty( $call['class'] ) ) {
 976                         $msg .= $call['class'] . '::';
 977                 }
 978                 $msg .= $call['function'] . '()';
 979
 980                 if ( $wgCommandLineMode ) {
 981                         $msg .= "\n";
 982                 } else {
 983                         $msg .= "</li>\n";
 984                 }
 985         }
 986         if ( $wgCommandLineMode ) {
 987                 $msg .= "\n";
 988         } else {
 989                 $msg .= "</ul>\n";
 990         }
 991
 992         return $msg;
 993 }
 994
 995
 996 /* Some generic result counters, pulled out of SearchEngine */
 997
 998
 999 /**
1000  * @todo document
1001  */
1002 function wfShowingResults( $offset, $limit ) {
1003         global $wgLang;
1004         return wfMsgExt(
1005                 'showingresults',
1006                 array( 'parseinline' ),
1007                 $wgLang->formatNum( $limit ),
1008                 $wgLang->formatNum( $offset + 1 )
1009         );
1010 }
1011
1012 /**
1013  * @todo document
1014  */
1015 function wfShowingResultsNum( $offset, $limit, $num ) {
1016         global $wgLang;
1017         return wfMsgExt(
1018                 'showingresultsnum',
1019                 array( 'parseinline' ),
1020                 $wgLang->formatNum( $limit ),
1021                 $wgLang->formatNum( $offset + 1 ),
1022                 $wgLang->formatNum( $num )
1023         );
1024 }
1025
1026 /**
1027  * Generate (prev x| next x) (20|50|100...) type links for paging
1028  * @param $offset String
1029  * @param $limit Integer
1030  * @param $link String
1031  * @param $query String: optional URL query parameter string
1032  * @param $atend Bool: optional param for specified if this is the last page
1033  */
1034 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1035         global $wgLang;
1036         $fmtLimit = $wgLang->formatNum( $limit );
1037         // FIXME: Why on earth this needs one message for the text and another one for tooltip??
1038         # Get prev/next link display text
1039         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1040         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1041         # Get prev/next link title text
1042         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1043         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1044         # Fetch the title object
1045         if( is_object( $link ) ) {
1046                 $title =& $link;
1047         } else {
1048                 $title = Title::newFromText( $link );
1049                 if( is_null( $title ) ) {
1050                         return false;
1051                 }
1052         }
1053         # Make 'previous' link
1054         if( 0 != $offset ) {
1055                 $po = $offset - $limit;
1056                 $po = max( $po, 0 );
1057                 $q = "limit={$limit}&offset={$po}";
1058                 if( $query != '' ) {
1059                         $q .= '&' . $query;
1060                 }
1061                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1062         } else {
1063                 $plink = $prev;
1064         }
1065         # Make 'next' link
1066         $no = $offset + $limit;
1067         $q = "limit={$limit}&offset={$no}";
1068         if( $query != '' ) {
1069                 $q .= '&' . $query;
1070         }
1071         if( $atend ) {
1072                 $nlink = $next;
1073         } else {
1074                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1075         }
1076         # Make links to set number of items per page
1077         $nums = $wgLang->pipeList( array(
1078                 wfNumLink( $offset, 20, $title, $query ),
1079                 wfNumLink( $offset, 50, $title, $query ),
1080                 wfNumLink( $offset, 100, $title, $query ),
1081                 wfNumLink( $offset, 250, $title, $query ),
1082                 wfNumLink( $offset, 500, $title, $query )
1083         ) );
1084         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1085 }
1086
1087 /**
1088  * Generate links for (20|50|100...) items-per-page links
1089  * @param $offset String
1090  * @param $limit Integer
1091  * @param $title Title
1092  * @param $query String: optional URL query parameter string
1093  */
1094 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1095         global $wgLang;
1096         if( $query == '' ) {
1097                 $q = '';
1098         } else {
1099                 $q = $query.'&';
1100         }
1101         $q .= "limit={$limit}&offset={$offset}";
1102         $fmtLimit = $wgLang->formatNum( $limit );
1103         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1104         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1105         return $s;
1106 }
1107
1108 /**
1109  * @todo document
1110  * @todo FIXME: we may want to blacklist some broken browsers
1111  *
1112  * @return bool Whereas client accept gzip compression
1113  */
1114 function wfClientAcceptsGzip( $force = false ) {
1115         static $result = null;
1116         if ( $result === null || $force ) {
1117                 $result = false;
1118                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1119                         # FIXME: we may want to blacklist some broken browsers
1120                         $m = array();
1121                         if( preg_match(
1122                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1123                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1124                                 $m )
1125                         )
1126                         {
1127                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1128                                         $result = false;
1129                                         return $result;
1130                                 }
1131                                 wfDebug( " accepts gzip\n" );
1132                                 $result = true;
1133                         }
1134                 }
1135         }
1136         return $result;
1137 }
1138
1139 /**
1140  * Obtain the offset and limit values from the request string;
1141  * used in special pages
1142  *
1143  * @param $deflimit Default limit if none supplied
1144  * @param $optionname Name of a user preference to check against
1145  * @return array
1146  *
1147  */
1148 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1149         global $wgRequest;
1150         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1151 }
1152
1153 /**
1154  * Escapes the given text so that it may be output using addWikiText()
1155  * without any linking, formatting, etc. making its way through. This
1156  * is achieved by substituting certain characters with HTML entities.
1157  * As required by the callers, <nowiki> is not used. It currently does
1158  * not filter out characters which have special meaning only at the
1159  * start of a line, such as "*".
1160  *
1161  * @param $text String: text to be escaped
1162  */
1163 function wfEscapeWikiText( $text ) {
1164         $text = str_replace(
1165                 array( '[',     '|',      ']',     '\'',    'ISBN ',
1166                         'RFC ',     '://',     "\n=",     '{{',           '}}' ),
1167                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;',
1168                         'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;', '&#125;&#125;' ),
1169                 htmlspecialchars( $text )
1170         );
1171         return $text;
1172 }
1173
1174 /**
1175  * @todo document
1176  * @return float
1177  */
1178 function wfTime() {
1179         return microtime( true );
1180 }
1181
1182 /**
1183  * Sets dest to source and returns the original value of dest
1184  * If source is NULL, it just returns the value, it doesn't set the variable
1185  * If force is true, it will set the value even if source is NULL
1186  */
1187 function wfSetVar( &$dest, $source, $force = false ) {
1188         $temp = $dest;
1189         if ( !is_null( $source ) || $force ) {
1190                 $dest = $source;
1191         }
1192         return $temp;
1193 }
1194
1195 /**
1196  * As for wfSetVar except setting a bit
1197  */
1198 function wfSetBit( &$dest, $bit, $state = true ) {
1199         $temp = (bool)( $dest & $bit );
1200         if ( !is_null( $state ) ) {
1201                 if ( $state ) {
1202                         $dest |= $bit;
1203                 } else {
1204                         $dest &= ~$bit;
1205                 }
1206         }
1207         return $temp;
1208 }
1209
1210 /**
1211  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1212  * "days=7&limit=100". Options in the first array override options in the second.
1213  * Options set to "" will not be output.
1214  */
1215 function wfArrayToCGI( $array1, $array2 = null ) {
1216         if ( !is_null( $array2 ) ) {
1217                 $array1 = $array1 + $array2;
1218         }
1219
1220         $cgi = '';
1221         foreach ( $array1 as $key => $value ) {
1222                 if ( $value !== '' ) {
1223                         if ( $cgi != '' ) {
1224                                 $cgi .= '&';
1225                         }
1226                         if ( is_array( $value ) ) {
1227                                 $firstTime = true;
1228                                 foreach ( $value as $v ) {
1229                                         $cgi .= ( $firstTime ? '' : '&') .
1230                                                 urlencode( $key . '[]' ) . '=' .
1231                                                 urlencode( $v );
1232                                         $firstTime = false;
1233                                 }
1234                         } else {
1235                                 if ( is_object( $value ) ) {
1236                                         $value = $value->__toString();
1237                                 }
1238                                 $cgi .= urlencode( $key ) . '=' .
1239                                         urlencode( $value );
1240                         }
1241                 }
1242         }
1243         return $cgi;
1244 }
1245
1246 /**
1247  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1248  * its argument and returns the same string in array form.  This allows compa-
1249  * tibility with legacy functions that accept raw query strings instead of nice
1250  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1251  * valid query strings, or it will explode.
1252  *
1253  * @param $query String: query string
1254  * @return array Array version of input
1255  */
1256 function wfCgiToArray( $query ) {
1257         if( isset( $query[0] ) && $query[0] == '?' ) {
1258                 $query = substr( $query, 1 );
1259         }
1260         $bits = explode( '&', $query );
1261         $ret = array();
1262         foreach( $bits as $bit ) {
1263                 if( $bit === '' ) {
1264                         continue;
1265                 }
1266                 list( $key, $value ) = explode( '=', $bit );
1267                 $key = urldecode( $key );
1268                 $value = urldecode( $value );
1269                 $ret[$key] = $value;
1270         }
1271         return $ret;
1272 }
1273
1274 /**
1275  * Append a query string to an existing URL, which may or may not already
1276  * have query string parameters already. If so, they will be combined.
1277  *
1278  * @param $url String
1279  * @param $query Mixed: string or associative array
1280  * @return string
1281  */
1282 function wfAppendQuery( $url, $query ) {
1283         if ( is_array( $query ) ) {
1284                 $query = wfArrayToCGI( $query );
1285         }
1286         if( $query != '' ) {
1287                 if( false === strpos( $url, '?' ) ) {
1288                         $url .= '?';
1289                 } else {
1290                         $url .= '&';
1291                 }
1292                 $url .= $query;
1293         }
1294         return $url;
1295 }
1296
1297 /**
1298  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1299  * and $wgProto are correct.
1300  *
1301  * @todo this won't work with current-path-relative URLs
1302  * like "subdir/foo.html", etc.
1303  *
1304  * @param $url String: either fully-qualified or a local path + query
1305  * @return string Fully-qualified URL
1306  */
1307 function wfExpandUrl( $url ) {
1308         if( substr( $url, 0, 2 ) == '//' ) {
1309                 global $wgProto;
1310                 return $wgProto . ':' . $url;
1311         } elseif( substr( $url, 0, 1 ) == '/' ) {
1312                 global $wgServer;
1313                 return $wgServer . $url;
1314         } else {
1315                 return $url;
1316         }
1317 }
1318
1319 /**
1320  * Windows-compatible version of escapeshellarg()
1321  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1322  * function puts single quotes in regardless of OS.
1323  *
1324  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1325  * earlier distro releases of PHP)
1326  */
1327 function wfEscapeShellArg( ) {
1328         wfInitShellLocale();
1329
1330         $args = func_get_args();
1331         $first = true;
1332         $retVal = '';
1333         foreach ( $args as $arg ) {
1334                 if ( !$first ) {
1335                         $retVal .= ' ';
1336                 } else {
1337                         $first = false;
1338                 }
1339
1340                 if ( wfIsWindows() ) {
1341                         // Escaping for an MSVC-style command line parser and CMD.EXE
1342                         // Refs:
1343                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1344                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1345                         //  * Bug #13518
1346                         //  * CR r63214
1347                         // Double the backslashes before any double quotes. Escape the double quotes.
1348                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1349                         $arg = '';
1350                         $iteration = 0;
1351                         foreach ( $tokens as $token ) {
1352                                 if ( $iteration % 2 == 1 ) {
1353                                         // Delimiter, a double quote preceded by zero or more slashes
1354                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1355                                 } elseif ( $iteration % 4 == 2 ) {
1356                                         // ^ in $token will be outside quotes, need to be escaped
1357                                         $arg .= str_replace( '^', '^^', $token );
1358                                 } else { // $iteration % 4 == 0
1359                                         // ^ in $token will appear inside double quotes, so leave as is
1360                                         $arg .= $token;
1361                                 }
1362                                 $iteration++;
1363                         }
1364                         // Double the backslashes before the end of the string, because
1365                         // we will soon add a quote
1366                         $m = array();
1367                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1368                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1369                         }
1370
1371                         // Add surrounding quotes
1372                         $retVal .= '"' . $arg . '"';
1373                 } else {
1374                         $retVal .= escapeshellarg( $arg );
1375                 }
1376         }
1377         return $retVal;
1378 }
1379
1380 /**
1381  * wfMerge attempts to merge differences between three texts.
1382  * Returns true for a clean merge and false for failure or a conflict.
1383  */
1384 function wfMerge( $old, $mine, $yours, &$result ) {
1385         global $wgDiff3;
1386
1387         # This check may also protect against code injection in
1388         # case of broken installations.
1389         wfSuppressWarnings();
1390         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1391         wfRestoreWarnings();
1392
1393         if( !$haveDiff3 ) {
1394                 wfDebug( "diff3 not found\n" );
1395                 return false;
1396         }
1397
1398         # Make temporary files
1399         $td = wfTempDir();
1400         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1401         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1402         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1403
1404         fwrite( $oldtextFile, $old );
1405         fclose( $oldtextFile );
1406         fwrite( $mytextFile, $mine );
1407         fclose( $mytextFile );
1408         fwrite( $yourtextFile, $yours );
1409         fclose( $yourtextFile );
1410
1411         # Check for a conflict
1412         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1413                 wfEscapeShellArg( $mytextName ) . ' ' .
1414                 wfEscapeShellArg( $oldtextName ) . ' ' .
1415                 wfEscapeShellArg( $yourtextName );
1416         $handle = popen( $cmd, 'r' );
1417
1418         if( fgets( $handle, 1024 ) ) {
1419                 $conflict = true;
1420         } else {
1421                 $conflict = false;
1422         }
1423         pclose( $handle );
1424
1425         # Merge differences
1426         $cmd = $wgDiff3 . ' -a -e --merge ' .
1427                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1428         $handle = popen( $cmd, 'r' );
1429         $result = '';
1430         do {
1431                 $data = fread( $handle, 8192 );
1432                 if ( strlen( $data ) == 0 ) {
1433                         break;
1434                 }
1435                 $result .= $data;
1436         } while ( true );
1437         pclose( $handle );
1438         unlink( $mytextName );
1439         unlink( $oldtextName );
1440         unlink( $yourtextName );
1441
1442         if ( $result === '' && $old !== '' && !$conflict ) {
1443                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1444                 $conflict = true;
1445         }
1446         return !$conflict;
1447 }
1448
1449 /**
1450  * Returns unified plain-text diff of two texts.
1451  * Useful for machine processing of diffs.
1452  * @param $before String: the text before the changes.
1453  * @param $after String: the text after the changes.
1454  * @param $params String: command-line options for the diff command.
1455  * @return String: unified diff of $before and $after
1456  */
1457 function wfDiff( $before, $after, $params = '-u' ) {
1458         if ( $before == $after ) {
1459                 return '';
1460         }
1461
1462         global $wgDiff;
1463         wfSuppressWarnings();
1464         $haveDiff = $wgDiff && file_exists( $wgDiff );
1465         wfRestoreWarnings();
1466
1467         # This check may also protect against code injection in
1468         # case of broken installations.
1469         if( !$haveDiff ) {
1470                 wfDebug( "diff executable not found\n" );
1471                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1472                 $format = new UnifiedDiffFormatter();
1473                 return $format->format( $diffs );
1474         }
1475
1476         # Make temporary files
1477         $td = wfTempDir();
1478         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1479         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1480
1481         fwrite( $oldtextFile, $before );
1482         fclose( $oldtextFile );
1483         fwrite( $newtextFile, $after );
1484         fclose( $newtextFile );
1485
1486         // Get the diff of the two files
1487         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1488
1489         $h = popen( $cmd, 'r' );
1490
1491         $diff = '';
1492
1493         do {
1494                 $data = fread( $h, 8192 );
1495                 if ( strlen( $data ) == 0 ) {
1496                         break;
1497                 }
1498                 $diff .= $data;
1499         } while ( true );
1500
1501         // Clean up
1502         pclose( $h );
1503         unlink( $oldtextName );
1504         unlink( $newtextName );
1505
1506         // Kill the --- and +++ lines. They're not useful.
1507         $diff_lines = explode( "\n", $diff );
1508         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1509                 unset( $diff_lines[0] );
1510         }
1511         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1512                 unset( $diff_lines[1] );
1513         }
1514
1515         $diff = implode( "\n", $diff_lines );
1516
1517         return $diff;
1518 }
1519
1520 /**
1521  * A wrapper around the PHP function var_export().
1522  * Either print it or add it to the regular output ($wgOut).
1523  *
1524  * @param $var A PHP variable to dump.
1525  */
1526 function wfVarDump( $var ) {
1527         global $wgOut;
1528         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1529         if ( headers_sent() || !@is_object( $wgOut ) ) {
1530                 print $s;
1531         } else {
1532                 $wgOut->addHTML( $s );
1533         }
1534 }
1535
1536 /**
1537  * Provide a simple HTTP error.
1538  */
1539 function wfHttpError( $code, $label, $desc ) {
1540         global $wgOut;
1541         $wgOut->disable();
1542         header( "HTTP/1.0 $code $label" );
1543         header( "Status: $code $label" );
1544         $wgOut->sendCacheControl();
1545
1546         header( 'Content-type: text/html; charset=utf-8' );
1547         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1548                 '<html><head><title>' .
1549                 htmlspecialchars( $label ) .
1550                 '</title></head><body><h1>' .
1551                 htmlspecialchars( $label ) .
1552                 '</h1><p>' .
1553                 nl2br( htmlspecialchars( $desc ) ) .
1554                 "</p></body></html>\n";
1555 }
1556
1557 /**
1558  * Clear away any user-level output buffers, discarding contents.
1559  *
1560  * Suitable for 'starting afresh', for instance when streaming
1561  * relatively large amounts of data without buffering, or wanting to
1562  * output image files without ob_gzhandler's compression.
1563  *
1564  * The optional $resetGzipEncoding parameter controls suppression of
1565  * the Content-Encoding header sent by ob_gzhandler; by default it
1566  * is left. See comments for wfClearOutputBuffers() for why it would
1567  * be used.
1568  *
1569  * Note that some PHP configuration options may add output buffer
1570  * layers which cannot be removed; these are left in place.
1571  *
1572  * @param $resetGzipEncoding Bool
1573  */
1574 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1575         if( $resetGzipEncoding ) {
1576                 // Suppress Content-Encoding and Content-Length
1577                 // headers from 1.10+s wfOutputHandler
1578                 global $wgDisableOutputCompression;
1579                 $wgDisableOutputCompression = true;
1580         }
1581         while( $status = ob_get_status() ) {
1582                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1583                         // Probably from zlib.output_compression or other
1584                         // PHP-internal setting which can't be removed.
1585                         //
1586                         // Give up, and hope the result doesn't break
1587                         // output behavior.
1588                         break;
1589                 }
1590                 if( !ob_end_clean() ) {
1591                         // Could not remove output buffer handler; abort now
1592                         // to avoid getting in some kind of infinite loop.
1593                         break;
1594                 }
1595                 if( $resetGzipEncoding ) {
1596                         if( $status['name'] == 'ob_gzhandler' ) {
1597                                 // Reset the 'Content-Encoding' field set by this handler
1598                                 // so we can start fresh.
1599                                 header( 'Content-Encoding:' );
1600                                 break;
1601                         }
1602                 }
1603         }
1604 }
1605
1606 /**
1607  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1608  *
1609  * Clear away output buffers, but keep the Content-Encoding header
1610  * produced by ob_gzhandler, if any.
1611  *
1612  * This should be used for HTTP 304 responses, where you need to
1613  * preserve the Content-Encoding header of the real result, but
1614  * also need to suppress the output of ob_gzhandler to keep to spec
1615  * and avoid breaking Firefox in rare cases where the headers and
1616  * body are broken over two packets.
1617  */
1618 function wfClearOutputBuffers() {
1619         wfResetOutputBuffers( false );
1620 }
1621
1622 /**
1623  * Converts an Accept-* header into an array mapping string values to quality
1624  * factors
1625  */
1626 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1627         # No arg means accept anything (per HTTP spec)
1628         if( !$accept ) {
1629                 return array( $def => 1.0 );
1630         }
1631
1632         $prefs = array();
1633
1634         $parts = explode( ',', $accept );
1635
1636         foreach( $parts as $part ) {
1637                 # FIXME: doesn't deal with params like 'text/html; level=1'
1638                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1639                 $match = array();
1640                 if( !isset( $qpart ) ) {
1641                         $prefs[$value] = 1.0;
1642                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1643                         $prefs[$value] = floatval( $match[1] );
1644                 }
1645         }
1646
1647         return $prefs;
1648 }
1649
1650 /**
1651  * Checks if a given MIME type matches any of the keys in the given
1652  * array. Basic wildcards are accepted in the array keys.
1653  *
1654  * Returns the matching MIME type (or wildcard) if a match, otherwise
1655  * NULL if no match.
1656  *
1657  * @param $type String
1658  * @param $avail Array
1659  * @return string
1660  * @private
1661  */
1662 function mimeTypeMatch( $type, $avail ) {
1663         if( array_key_exists( $type, $avail ) ) {
1664                 return $type;
1665         } else {
1666                 $parts = explode( '/', $type );
1667                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1668                         return $parts[0] . '/*';
1669                 } elseif( array_key_exists( '*/*', $avail ) ) {
1670                         return '*/*';
1671                 } else {
1672                         return null;
1673                 }
1674         }
1675 }
1676
1677 /**
1678  * Returns the 'best' match between a client's requested internet media types
1679  * and the server's list of available types. Each list should be an associative
1680  * array of type to preference (preference is a float between 0.0 and 1.0).
1681  * Wildcards in the types are acceptable.
1682  *
1683  * @param $cprefs Array: client's acceptable type list
1684  * @param $sprefs Array: server's offered types
1685  * @return string
1686  *
1687  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1688  * XXX: generalize to negotiate other stuff
1689  */
1690 function wfNegotiateType( $cprefs, $sprefs ) {
1691         $combine = array();
1692
1693         foreach( array_keys($sprefs) as $type ) {
1694                 $parts = explode( '/', $type );
1695                 if( $parts[1] != '*' ) {
1696                         $ckey = mimeTypeMatch( $type, $cprefs );
1697                         if( $ckey ) {
1698                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1699                         }
1700                 }
1701         }
1702
1703         foreach( array_keys( $cprefs ) as $type ) {
1704                 $parts = explode( '/', $type );
1705                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1706                         $skey = mimeTypeMatch( $type, $sprefs );
1707                         if( $skey ) {
1708                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1709                         }
1710                 }
1711         }
1712
1713         $bestq = 0;
1714         $besttype = null;
1715
1716         foreach( array_keys( $combine ) as $type ) {
1717                 if( $combine[$type] > $bestq ) {
1718                         $besttype = $type;
1719                         $bestq = $combine[$type];
1720                 }
1721         }
1722
1723         return $besttype;
1724 }
1725
1726 /**
1727  * Array lookup
1728  * Returns an array where the values in the first array are replaced by the
1729  * values in the second array with the corresponding keys
1730  *
1731  * @return array
1732  */
1733 function wfArrayLookup( $a, $b ) {
1734         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1735 }
1736
1737 /**
1738  * Convenience function; returns MediaWiki timestamp for the present time.
1739  * @return string
1740  */
1741 function wfTimestampNow() {
1742         # return NOW
1743         return wfTimestamp( TS_MW, time() );
1744 }
1745
1746 /**
1747  * Reference-counted warning suppression
1748  */
1749 function wfSuppressWarnings( $end = false ) {
1750         static $suppressCount = 0;
1751         static $originalLevel = false;
1752
1753         if ( $end ) {
1754                 if ( $suppressCount ) {
1755                         --$suppressCount;
1756                         if ( !$suppressCount ) {
1757                                 error_reporting( $originalLevel );
1758                         }
1759                 }
1760         } else {
1761                 if ( !$suppressCount ) {
1762                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE ) );
1763                 }
1764                 ++$suppressCount;
1765         }
1766 }
1767
1768 /**
1769  * Restore error level to previous value
1770  */
1771 function wfRestoreWarnings() {
1772         wfSuppressWarnings( true );
1773 }
1774
1775 # Autodetect, convert and provide timestamps of various types
1776
1777 /**
1778  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1779  */
1780 define( 'TS_UNIX', 0 );
1781
1782 /**
1783  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1784  */
1785 define( 'TS_MW', 1 );
1786
1787 /**
1788  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1789  */
1790 define( 'TS_DB', 2 );
1791
1792 /**
1793  * RFC 2822 format, for E-mail and HTTP headers
1794  */
1795 define( 'TS_RFC2822', 3 );
1796
1797 /**
1798  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1799  *
1800  * This is used by Special:Export
1801  */
1802 define( 'TS_ISO_8601', 4 );
1803
1804 /**
1805  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1806  *
1807  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1808  *       DateTime tag and page 36 for the DateTimeOriginal and
1809  *       DateTimeDigitized tags.
1810  */
1811 define( 'TS_EXIF', 5 );
1812
1813 /**
1814  * Oracle format time.
1815  */
1816 define( 'TS_ORACLE', 6 );
1817
1818 /**
1819  * Postgres format time.
1820  */
1821 define( 'TS_POSTGRES', 7 );
1822
1823 /**
1824  * DB2 format time
1825  */
1826 define( 'TS_DB2', 8 );
1827
1828 /**
1829  * ISO 8601 basic format with no timezone: 19860209T200000Z
1830  *
1831  * This is used by ResourceLoader
1832  */
1833 define( 'TS_ISO_8601_BASIC', 9 );
1834
1835 /**
1836  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
1837  *                    function will autodetect which format is supplied and act
1838  *                    accordingly.
1839  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
1840  * @return Mixed: String / false The same date in the format specified in $outputtype or false
1841  */
1842 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1843         $uts = 0;
1844         $da = array();
1845         $strtime = '';
1846
1847         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
1848                 $uts = time();
1849                 $strtime = "@$uts";
1850         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1851                 # TS_DB
1852         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1853                 # TS_EXIF
1854         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
1855                 # TS_MW
1856         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
1857                 # TS_UNIX
1858                 $uts = $ts;
1859                 $strtime = "@$ts"; // Undocumented?
1860         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
1861                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
1862                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1863                                 str_replace( '+00:00', 'UTC', $ts ) );
1864         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1865                 # TS_ISO_8601
1866         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1867                 #TS_ISO_8601_BASIC
1868         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
1869                 # TS_POSTGRES
1870         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
1871                 # TS_POSTGRES
1872         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
1873                 # TS_DB2
1874         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
1875                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
1876                                                         '[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d/S', $ts ) ) { # hh:mm:ss
1877                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
1878                 # The regex is a superset of rfc2822 for readability
1879                 $strtime = strtok( $ts, ';' );
1880         } elseif ( preg_match( '/^[A-Z][a-z]{5,8}, \d\d-[A-Z][a-z]{2}-\d{2} \d\d:\d\d:\d\d/', $ts ) ) {
1881                 # TS_RFC850
1882                 $strtime = $ts;
1883         } elseif ( preg_match( '/^[A-Z][a-z]{2} [A-Z][a-z]{2} +\d{1,2} \d\d:\d\d:\d\d \d{4}/', $ts ) ) {
1884                 # asctime
1885                 $strtime = $ts;
1886         } else {
1887                 # Bogus value...
1888                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
1889
1890                 return false;
1891         }
1892
1893
1894
1895         static $formats = array(
1896                 TS_UNIX => 'U',
1897                 TS_MW => 'YmdHis',
1898                 TS_DB => 'Y-m-d H:i:s',
1899                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
1900                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
1901                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
1902                 TS_RFC2822 => 'D, d M Y H:i:s',
1903                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
1904                 TS_POSTGRES => 'Y-m-d H:i:s',
1905                 TS_DB2 => 'Y-m-d H:i:s',
1906         );
1907
1908         if ( !isset( $formats[$outputtype] ) ) {
1909                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
1910         }
1911
1912         if ( function_exists( "date_create" ) ) {
1913                 if ( count( $da ) ) {
1914                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
1915                                 (int)$da[1], (int)$da[2], (int)$da[3],
1916                                 (int)$da[4], (int)$da[5], (int)$da[6]);
1917
1918                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
1919                 } elseif ( $strtime ) {
1920                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
1921                 } else {
1922                         return false;
1923                 }
1924
1925                 if ( !$d ) {
1926                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1927                         return false;
1928                 }
1929
1930                 $output = $d->format( $formats[$outputtype] );
1931         } else {
1932                 if ( count( $da ) ) {
1933                         // Warning! gmmktime() acts oddly if the month or day is set to 0
1934                         // We may want to handle that explicitly at some point
1935                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
1936                                 (int)$da[2], (int)$da[3], (int)$da[1] );
1937                 } elseif ( $strtime ) {
1938                         $uts = strtotime( $strtime );
1939                 }
1940
1941                 if ( $uts === false ) {
1942                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
1943                         return false;
1944                 }
1945
1946                 if ( TS_UNIX == $outputtype ) {
1947                         return $uts;
1948                 }
1949                 $output = gmdate( $formats[$outputtype], $uts );
1950         }
1951
1952         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
1953                 $output .= ' GMT';
1954         }
1955
1956         return $output;
1957 }
1958
1959 /**
1960  * Return a formatted timestamp, or null if input is null.
1961  * For dealing with nullable timestamp columns in the database.
1962  * @param $outputtype Integer
1963  * @param $ts String
1964  * @return String
1965  */
1966 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1967         if( is_null( $ts ) ) {
1968                 return null;
1969         } else {
1970                 return wfTimestamp( $outputtype, $ts );
1971         }
1972 }
1973
1974 /**
1975  * Check if the operating system is Windows
1976  *
1977  * @return Bool: true if it's Windows, False otherwise.
1978  */
1979 function wfIsWindows() {
1980         static $isWindows = null;
1981         if ( $isWindows === null ) {
1982                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
1983         }
1984         return $isWindows;
1985 }
1986
1987 /**
1988  * Swap two variables
1989  */
1990 function swap( &$x, &$y ) {
1991         $z = $x;
1992         $x = $y;
1993         $y = $z;
1994 }
1995
1996 function wfGetCachedNotice( $name ) {
1997         global $wgOut, $wgRenderHashAppend, $parserMemc;
1998         $fname = 'wfGetCachedNotice';
1999         wfProfileIn( $fname );
2000
2001         $needParse = false;
2002
2003         if( $name === 'default' ) {
2004                 // special case
2005                 global $wgSiteNotice;
2006                 $notice = $wgSiteNotice;
2007                 if( empty( $notice ) ) {
2008                         wfProfileOut( $fname );
2009                         return false;
2010                 }
2011         } else {
2012                 $notice = wfMsgForContentNoTrans( $name );
2013                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
2014                         wfProfileOut( $fname );
2015                         return( false );
2016                 }
2017         }
2018
2019         // Use the extra hash appender to let eg SSL variants separately cache.
2020         $key = wfMemcKey( $name . $wgRenderHashAppend );
2021         $cachedNotice = $parserMemc->get( $key );
2022         if( is_array( $cachedNotice ) ) {
2023                 if( md5( $notice ) == $cachedNotice['hash'] ) {
2024                         $notice = $cachedNotice['html'];
2025                 } else {
2026                         $needParse = true;
2027                 }
2028         } else {
2029                 $needParse = true;
2030         }
2031
2032         if( $needParse ) {
2033                 if( is_object( $wgOut ) ) {
2034                         $parsed = $wgOut->parse( $notice );
2035                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
2036                         $notice = $parsed;
2037                 } else {
2038                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' . "\n" );
2039                         $notice = '';
2040                 }
2041         }
2042         $notice = '<div id="localNotice">' .$notice . '</div>';
2043         wfProfileOut( $fname );
2044         return $notice;
2045 }
2046
2047 function wfGetNamespaceNotice() {
2048         global $wgTitle;
2049
2050         # Paranoia
2051         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) ) {
2052                 return '';
2053         }
2054
2055         $fname = 'wfGetNamespaceNotice';
2056         wfProfileIn( $fname );
2057
2058         $key = 'namespacenotice-' . $wgTitle->getNsText();
2059         $namespaceNotice = wfGetCachedNotice( $key );
2060         if ( $namespaceNotice && substr( $namespaceNotice, 0, 7 ) != '<p>&lt;' ) {
2061                 $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . '</div>';
2062         } else {
2063                 $namespaceNotice = '';
2064         }
2065
2066         wfProfileOut( $fname );
2067         return $namespaceNotice;
2068 }
2069
2070 function wfGetSiteNotice() {
2071         global $wgUser;
2072         $fname = 'wfGetSiteNotice';
2073         wfProfileIn( $fname );
2074         $siteNotice = '';
2075
2076         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
2077                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
2078                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
2079                 } else {
2080                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
2081                         if( !$anonNotice ) {
2082                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
2083                         } else {
2084                                 $siteNotice = $anonNotice;
2085                         }
2086                 }
2087                 if( !$siteNotice ) {
2088                         $siteNotice = wfGetCachedNotice( 'default' );
2089                 }
2090         }
2091
2092         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
2093         wfProfileOut( $fname );
2094         return $siteNotice;
2095 }
2096
2097 /**
2098  * BC wrapper for MimeMagic::singleton()
2099  * @deprecated No longer needed as of 1.17 (r68836). Remove in 1.19.
2100  */
2101 function &wfGetMimeMagic() {
2102         wfDeprecated( __FUNCTION__ );
2103         return MimeMagic::singleton();
2104 }
2105
2106 /**
2107  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2108  * TEMP environment variables are then checked in sequence, and if none are set
2109  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2110  * or C:\Windows\Temp for Windows and hope for the best.
2111  * It is common to call it with tempnam().
2112  *
2113  * NOTE: When possible, use instead the tmpfile() function to create
2114  * temporary files to avoid race conditions on file creation, etc.
2115  *
2116  * @return String
2117  */
2118 function wfTempDir() {
2119         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2120                 $tmp = getenv( $var );
2121                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2122                         return $tmp;
2123                 }
2124         }
2125         if( function_exists( 'sys_get_temp_dir' ) ) {
2126                 return sys_get_temp_dir();
2127         }
2128         # Usual defaults
2129         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2130 }
2131
2132 /**
2133  * Make directory, and make all parent directories if they don't exist
2134  *
2135  * @param $dir String: full path to directory to create
2136  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2137  * @param $caller String: optional caller param for debugging.
2138  * @return bool
2139  */
2140 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2141         global $wgDirectoryMode;
2142
2143         if ( !is_null( $caller ) ) {
2144                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2145         }
2146
2147         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2148                 return true;
2149         }
2150
2151         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2152
2153         if ( is_null( $mode ) ) {
2154                 $mode = $wgDirectoryMode;
2155         }
2156
2157         // Turn off the normal warning, we're doing our own below
2158         wfSuppressWarnings();
2159         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2160         wfRestoreWarnings();
2161
2162         if( !$ok ) {
2163                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2164                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2165         }
2166         return $ok;
2167 }
2168
2169 /**
2170  * Increment a statistics counter
2171  */
2172 function wfIncrStats( $key ) {
2173         global $wgStatsMethod;
2174
2175         if( $wgStatsMethod == 'udp' ) {
2176                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
2177                 static $socket;
2178                 if ( !$socket ) {
2179                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2180                         $statline = "stats/{$wgDBname} - 1 1 1 1 1 -total\n";
2181                         socket_sendto(
2182                                 $socket,
2183                                 $statline,
2184                                 strlen( $statline ),
2185                                 0,
2186                                 $wgUDPProfilerHost,
2187                                 $wgUDPProfilerPort
2188                         );
2189                 }
2190                 $statline = "stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
2191                 wfSuppressWarnings();
2192                 socket_sendto(
2193                         $socket,
2194                         $statline,
2195                         strlen( $statline ),
2196                         0,
2197                         $wgUDPProfilerHost,
2198                         $wgUDPProfilerPort
2199                 );
2200                 wfRestoreWarnings();
2201         } elseif( $wgStatsMethod == 'cache' ) {
2202                 global $wgMemc;
2203                 $key = wfMemcKey( 'stats', $key );
2204                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2205                         $wgMemc->add( $key, 1 );
2206                 }
2207         } else {
2208                 // Disabled
2209         }
2210 }
2211
2212 /**
2213  * @param $nr Mixed: the number to format
2214  * @param $acc Integer: the number of digits after the decimal point, default 2
2215  * @param $round Boolean: whether or not to round the value, default true
2216  * @return float
2217  */
2218 function wfPercent( $nr, $acc = 2, $round = true ) {
2219         $ret = sprintf( "%.${acc}f", $nr );
2220         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2221 }
2222
2223 /**
2224  * Encrypt a username/password.
2225  *
2226  * @param $userid Integer: ID of the user
2227  * @param $password String: password of the user
2228  * @return String: hashed password
2229  * @deprecated Use User::crypt() or User::oldCrypt() instead
2230  */
2231 function wfEncryptPassword( $userid, $password ) {
2232         wfDeprecated(__FUNCTION__);
2233         # Just wrap around User::oldCrypt()
2234         return User::oldCrypt( $password, $userid );
2235 }
2236
2237 /**
2238  * Appends to second array if $value differs from that in $default
2239  */
2240 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2241         if ( is_null( $changed ) ) {
2242                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
2243         }
2244         if ( $default[$key] !== $value ) {
2245                 $changed[$key] = $value;
2246         }
2247 }
2248
2249 /**
2250  * Since wfMsg() and co suck, they don't return false if the message key they
2251  * looked up didn't exist but a XHTML string, this function checks for the
2252  * nonexistance of messages by looking at wfMsg() output
2253  *
2254  * @param $key      String: the message key looked up
2255  * @return Boolean True if the message *doesn't* exist.
2256  */
2257 function wfEmptyMsg( $key ) {
2258         global $wgMessageCache;
2259         return $wgMessageCache->get( $key, /*useDB*/true, /*content*/false ) === false;
2260 }
2261
2262 /**
2263  * Find out whether or not a mixed variable exists in a string
2264  *
2265  * @param $needle String
2266  * @param $str String
2267  * @param $insensitive Boolean
2268  * @return Boolean
2269  */
2270 function in_string( $needle, $str, $insensitive = false ) {
2271         $func = 'strpos';
2272         if( $insensitive ) $func = 'stripos';
2273
2274         return $func( $str, $needle ) !== false;
2275 }
2276
2277 function wfSpecialList( $page, $details ) {
2278         global $wgContLang;
2279         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2280         return $page . $details;
2281 }
2282
2283 /**
2284  * Returns a regular expression of url protocols
2285  *
2286  * @return String
2287  */
2288 function wfUrlProtocols() {
2289         global $wgUrlProtocols;
2290
2291         static $retval = null;
2292         if ( !is_null( $retval ) ) {
2293                 return $retval;
2294         }
2295
2296         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2297         // with LocalSettings files from 1.5
2298         if ( is_array( $wgUrlProtocols ) ) {
2299                 $protocols = array();
2300                 foreach ( $wgUrlProtocols as $protocol ) {
2301                         $protocols[] = preg_quote( $protocol, '/' );
2302                 }
2303
2304                 $retval = implode( '|', $protocols );
2305         } else {
2306                 $retval = $wgUrlProtocols;
2307         }
2308         return $retval;
2309 }
2310
2311 /**
2312  * Safety wrapper around ini_get() for boolean settings.
2313  * The values returned from ini_get() are pre-normalized for settings
2314  * set via php.ini or php_flag/php_admin_flag... but *not*
2315  * for those set via php_value/php_admin_value.
2316  *
2317  * It's fairly common for people to use php_value instead of php_flag,
2318  * which can leave you with an 'off' setting giving a false positive
2319  * for code that just takes the ini_get() return value as a boolean.
2320  *
2321  * To make things extra interesting, setting via php_value accepts
2322  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2323  * Unrecognized values go false... again opposite PHP's own coercion
2324  * from string to bool.
2325  *
2326  * Luckily, 'properly' set settings will always come back as '0' or '1',
2327  * so we only have to worry about them and the 'improper' settings.
2328  *
2329  * I frickin' hate PHP... :P
2330  *
2331  * @param $setting String
2332  * @return Bool
2333  */
2334 function wfIniGetBool( $setting ) {
2335         $val = ini_get( $setting );
2336         // 'on' and 'true' can't have whitespace around them, but '1' can.
2337         return strtolower( $val ) == 'on'
2338                 || strtolower( $val ) == 'true'
2339                 || strtolower( $val ) == 'yes'
2340                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2341 }
2342
2343 /**
2344  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2345  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2346  *
2347  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2348  *                          should be omitted
2349  * @return Bool - Whether or not the extension is loaded
2350  */
2351 function wfDl( $extension ) {
2352         if( extension_loaded( $extension ) ) {
2353                 return true;
2354         }
2355
2356         $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2357                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2358
2359         if( $canDl ) {
2360                 wfSuppressWarnings();
2361                 dl( $extension . '.' . PHP_SHLIB_SUFFIX );
2362                 wfRestoreWarnings();
2363         }
2364         return extension_loaded( $extension );
2365 }
2366
2367 /**
2368  * Execute a shell command, with time and memory limits mirrored from the PHP
2369  * configuration if supported.
2370  * @param $cmd String Command line, properly escaped for shell.
2371  * @param &$retval optional, will receive the program's exit code.
2372  *                 (non-zero is usually failure)
2373  * @param $environ Array optional environment variables which should be
2374  *                 added to the executed command environment.
2375  * @return collected stdout as a string (trailing newlines stripped)
2376  */
2377 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2378         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2379
2380         static $disabled;
2381         if ( is_null( $disabled ) ) {
2382                 $disabled = false;
2383                 if( wfIniGetBool( 'safe_mode' ) ) {
2384                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2385                         $disabled = 'safemode';
2386                 } else {
2387                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2388                         $functions = array_map( 'trim', $functions );
2389                         $functions = array_map( 'strtolower', $functions );
2390                         if ( in_array( 'passthru', $functions ) ) {
2391                                 wfDebug( "passthru is in disabled_functions\n" );
2392                                 $disabled = 'passthru';
2393                         }
2394                 }
2395         }
2396         if ( $disabled ) {
2397                 $retval = 1;
2398                 return $disabled == 'safemode' ?
2399                         'Unable to run external programs in safe mode.' :
2400                         'Unable to run external programs, passthru() is disabled.';
2401         }
2402
2403         wfInitShellLocale();
2404
2405         $envcmd = '';
2406         foreach( $environ as $k => $v ) {
2407                 if ( wfIsWindows() ) {
2408                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2409                          * appear in the environment variable, so we must use carat escaping as documented in
2410                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2411                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2412                          * are listed there but doesn't appear to need it.
2413                          */
2414                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2415                 } else {
2416                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2417                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2418                          */
2419                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2420                 }
2421         }
2422         $cmd = $envcmd . $cmd;
2423
2424         if ( wfIsWindows() ) {
2425                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2426                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2427                 {
2428                         # Hack to work around PHP's flawed invocation of cmd.exe
2429                         # http://news.php.net/php.internals/21796
2430                         # Windows 9x doesn't accept any kind of quotes
2431                         $cmd = '"' . $cmd . '"';
2432                 }
2433         } elseif ( php_uname( 's' ) == 'Linux' ) {
2434                 $time = intval( $wgMaxShellTime );
2435                 $mem = intval( $wgMaxShellMemory );
2436                 $filesize = intval( $wgMaxShellFileSize );
2437
2438                 if ( $time > 0 && $mem > 0 ) {
2439                         $script = "$IP/bin/ulimit4.sh";
2440                         if ( is_executable( $script ) ) {
2441                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2442                         }
2443                 }
2444         }
2445         wfDebug( "wfShellExec: $cmd\n" );
2446
2447         $retval = 1; // error by default?
2448         ob_start();
2449         passthru( $cmd, $retval );
2450         $output = ob_get_contents();
2451         ob_end_clean();
2452
2453         if ( $retval == 127 ) {
2454                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2455         }
2456         return $output;
2457 }
2458
2459 /**
2460  * Workaround for http://bugs.php.net/bug.php?id=45132
2461  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2462  */
2463 function wfInitShellLocale() {
2464         static $done = false;
2465         if ( $done ) {
2466                 return;
2467         }
2468         $done = true;
2469         global $wgShellLocale;
2470         if ( !wfIniGetBool( 'safe_mode' ) ) {
2471                 putenv( "LC_CTYPE=$wgShellLocale" );
2472                 setlocale( LC_CTYPE, $wgShellLocale );
2473         }
2474 }
2475
2476 /**
2477  * This function works like "use VERSION" in Perl, the program will die with a
2478  * backtrace if the current version of PHP is less than the version provided
2479  *
2480  * This is useful for extensions which due to their nature are not kept in sync
2481  * with releases, and might depend on other versions of PHP than the main code
2482  *
2483  * Note: PHP might die due to parsing errors in some cases before it ever
2484  *       manages to call this function, such is life
2485  *
2486  * @see perldoc -f use
2487  *
2488  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2489  *                 a float
2490  */
2491 function wfUsePHP( $req_ver ) {
2492         $php_ver = PHP_VERSION;
2493
2494         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2495                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2496         }
2497 }
2498
2499 /**
2500  * This function works like "use VERSION" in Perl except it checks the version
2501  * of MediaWiki, the program will die with a backtrace if the current version
2502  * of MediaWiki is less than the version provided.
2503  *
2504  * This is useful for extensions which due to their nature are not kept in sync
2505  * with releases
2506  *
2507  * @see perldoc -f use
2508  *
2509  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2510  *                 a float
2511  */
2512 function wfUseMW( $req_ver ) {
2513         global $wgVersion;
2514
2515         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2516                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2517         }
2518 }
2519
2520 /**
2521  * Return the final portion of a pathname.
2522  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2523  * http://bugs.php.net/bug.php?id=33898
2524  *
2525  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2526  * We'll consider it so always, as we don't want \s in our Unix paths either.
2527  *
2528  * @param $path String
2529  * @param $suffix String: to remove if present
2530  * @return String
2531  */
2532 function wfBaseName( $path, $suffix = '' ) {
2533         $encSuffix = ( $suffix == '' )
2534                 ? ''
2535                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2536         $matches = array();
2537         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2538                 return $matches[1];
2539         } else {
2540                 return '';
2541         }
2542 }
2543
2544 /**
2545  * Generate a relative path name to the given file.
2546  * May explode on non-matching case-insensitive paths,
2547  * funky symlinks, etc.
2548  *
2549  * @param $path String: absolute destination path including target filename
2550  * @param $from String: Absolute source path, directory only
2551  * @return String
2552  */
2553 function wfRelativePath( $path, $from ) {
2554         // Normalize mixed input on Windows...
2555         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2556         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2557
2558         // Trim trailing slashes -- fix for drive root
2559         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2560         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2561
2562         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2563         $against = explode( DIRECTORY_SEPARATOR, $from );
2564
2565         if( $pieces[0] !== $against[0] ) {
2566                 // Non-matching Windows drive letters?
2567                 // Return a full path.
2568                 return $path;
2569         }
2570
2571         // Trim off common prefix
2572         while( count( $pieces ) && count( $against )
2573                 && $pieces[0] == $against[0] ) {
2574                 array_shift( $pieces );
2575                 array_shift( $against );
2576         }
2577
2578         // relative dots to bump us to the parent
2579         while( count( $against ) ) {
2580                 array_unshift( $pieces, '..' );
2581                 array_shift( $against );
2582         }
2583
2584         array_push( $pieces, wfBaseName( $path ) );
2585
2586         return implode( DIRECTORY_SEPARATOR, $pieces );
2587 }
2588
2589 /**
2590  * Backwards array plus for people who haven't bothered to read the PHP manual
2591  * XXX: will not darn your socks for you.
2592  *
2593  * @param $array1 Array
2594  * @param [$array2, [...]] Arrays
2595  * @return Array
2596  */
2597 function wfArrayMerge( $array1/* ... */ ) {
2598         $args = func_get_args();
2599         $args = array_reverse( $args, true );
2600         $out = array();
2601         foreach ( $args as $arg ) {
2602                 $out += $arg;
2603         }
2604         return $out;
2605 }
2606
2607 /**
2608  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
2609  * e.g.
2610  *      wfMergeErrorArrays(
2611  *              array( array( 'x' ) ),
2612  *              array( array( 'x', '2' ) ),
2613  *              array( array( 'x' ) ),
2614  *              array( array( 'y') )
2615  *      );
2616  * returns:
2617  *              array(
2618  *              array( 'x', '2' ),
2619  *              array( 'x' ),
2620  *              array( 'y' )
2621  *      )
2622  */
2623 function wfMergeErrorArrays( /*...*/ ) {
2624         $args = func_get_args();
2625         $out = array();
2626         foreach ( $args as $errors ) {
2627                 foreach ( $errors as $params ) {
2628                         # FIXME: sometimes get nested arrays for $params,
2629                         # which leads to E_NOTICEs
2630                         $spec = implode( "\t", $params );
2631                         $out[$spec] = $params;
2632                 }
2633         }
2634         return array_values( $out );
2635 }
2636
2637 /**
2638  * parse_url() work-alike, but non-broken.  Differences:
2639  *
2640  * 1) Does not raise warnings on bad URLs (just returns false)
2641  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2642  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2643  *
2644  * @param $url String: a URL to parse
2645  * @return Array: bits of the URL in an associative array, per PHP docs
2646  */
2647 function wfParseUrl( $url ) {
2648         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2649         wfSuppressWarnings();
2650         $bits = parse_url( $url );
2651         wfRestoreWarnings();
2652         if ( !$bits ) {
2653                 return false;
2654         }
2655
2656         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2657         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2658                 $bits['delimiter'] = '://';
2659         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2660                 $bits['delimiter'] = ':';
2661                 // parse_url detects for news: and mailto: the host part of an url as path
2662                 // We have to correct this wrong detection
2663                 if ( isset( $bits['path'] ) ) {
2664                         $bits['host'] = $bits['path'];
2665                         $bits['path'] = '';
2666                 }
2667         } else {
2668                 return false;
2669         }
2670
2671         return $bits;
2672 }
2673
2674 /**
2675  * Make a URL index, appropriate for the el_index field of externallinks.
2676  */
2677 function wfMakeUrlIndex( $url ) {
2678         $bits = wfParseUrl( $url );
2679
2680         // Reverse the labels in the hostname, convert to lower case
2681         // For emails reverse domainpart only
2682         if ( $bits['scheme'] == 'mailto' ) {
2683                 $mailparts = explode( '@', $bits['host'], 2 );
2684                 if ( count( $mailparts ) === 2 ) {
2685                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2686                 } else {
2687                         // No domain specified, don't mangle it
2688                         $domainpart = '';
2689                 }
2690                 $reversedHost = $domainpart . '@' . $mailparts[0];
2691         } else {
2692                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2693         }
2694         // Add an extra dot to the end
2695         // Why? Is it in wrong place in mailto links?
2696         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2697                 $reversedHost .= '.';
2698         }
2699         // Reconstruct the pseudo-URL
2700         $prot = $bits['scheme'];
2701         $index = $prot . $bits['delimiter'] . $reversedHost;
2702         // Leave out user and password. Add the port, path, query and fragment
2703         if ( isset( $bits['port'] ) ) {
2704                 $index .= ':' . $bits['port'];
2705         }
2706         if ( isset( $bits['path'] ) ) {
2707                 $index .= $bits['path'];
2708         } else {
2709                 $index .= '/';
2710         }
2711         if ( isset( $bits['query'] ) ) {
2712                 $index .= '?' . $bits['query'];
2713         }
2714         if ( isset( $bits['fragment'] ) ) {
2715                 $index .= '#' . $bits['fragment'];
2716         }
2717         return $index;
2718 }
2719
2720 /**
2721  * Do any deferred updates and clear the list
2722  *
2723  * @param $commit String: set to 'commit' to commit after every update to
2724  *                prevent lock contention
2725  */
2726 function wfDoUpdates( $commit = '' ) {
2727         global $wgDeferredUpdateList;
2728
2729         wfProfileIn( __METHOD__ );
2730
2731         // No need to get master connections in case of empty updates array
2732         if ( !count( $wgDeferredUpdateList ) ) {
2733                 wfProfileOut( __METHOD__ );
2734                 return;
2735         }
2736
2737         $doCommit = $commit == 'commit';
2738         if ( $doCommit ) {
2739                 $dbw = wfGetDB( DB_MASTER );
2740         }
2741
2742         foreach ( $wgDeferredUpdateList as $update ) {
2743                 $update->doUpdate();
2744
2745                 if ( $doCommit && $dbw->trxLevel() ) {
2746                         $dbw->commit();
2747                 }
2748         }
2749
2750         $wgDeferredUpdateList = array();
2751         wfProfileOut( __METHOD__ );
2752 }
2753
2754 /**
2755  * Convert an arbitrarily-long digit string from one numeric base
2756  * to another, optionally zero-padding to a minimum column width.
2757  *
2758  * Supports base 2 through 36; digit values 10-36 are represented
2759  * as lowercase letters a-z. Input is case-insensitive.
2760  *
2761  * @param $input String: of digits
2762  * @param $sourceBase Integer: 2-36
2763  * @param $destBase Integer: 2-36
2764  * @param $pad Integer: 1 or greater
2765  * @param $lowercase Boolean
2766  * @return String or false on invalid input
2767  */
2768 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2769         $input = strval( $input );
2770         if( $sourceBase < 2 ||
2771                 $sourceBase > 36 ||
2772                 $destBase < 2 ||
2773                 $destBase > 36 ||
2774                 $pad < 1 ||
2775                 $sourceBase != intval( $sourceBase ) ||
2776                 $destBase != intval( $destBase ) ||
2777                 $pad != intval( $pad ) ||
2778                 !is_string( $input ) ||
2779                 $input == '' ) {
2780                 return false;
2781         }
2782         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2783         $inDigits = array();
2784         $outChars = '';
2785
2786         // Decode and validate input string
2787         $input = strtolower( $input );
2788         for( $i = 0; $i < strlen( $input ); $i++ ) {
2789                 $n = strpos( $digitChars, $input{$i} );
2790                 if( $n === false || $n > $sourceBase ) {
2791                         return false;
2792                 }
2793                 $inDigits[] = $n;
2794         }
2795
2796         // Iterate over the input, modulo-ing out an output digit
2797         // at a time until input is gone.
2798         while( count( $inDigits ) ) {
2799                 $work = 0;
2800                 $workDigits = array();
2801
2802                 // Long division...
2803                 foreach( $inDigits as $digit ) {
2804                         $work *= $sourceBase;
2805                         $work += $digit;
2806
2807                         if( $work < $destBase ) {
2808                                 // Gonna need to pull another digit.
2809                                 if( count( $workDigits ) ) {
2810                                         // Avoid zero-padding; this lets us find
2811                                         // the end of the input very easily when
2812                                         // length drops to zero.
2813                                         $workDigits[] = 0;
2814                                 }
2815                         } else {
2816                                 // Finally! Actual division!
2817                                 $workDigits[] = intval( $work / $destBase );
2818
2819                                 // Isn't it annoying that most programming languages
2820                                 // don't have a single divide-and-remainder operator,
2821                                 // even though the CPU implements it that way?
2822                                 $work = $work % $destBase;
2823                         }
2824                 }
2825
2826                 // All that division leaves us with a remainder,
2827                 // which is conveniently our next output digit.
2828                 $outChars .= $digitChars[$work];
2829
2830                 // And we continue!
2831                 $inDigits = $workDigits;
2832         }
2833
2834         while( strlen( $outChars ) < $pad ) {
2835                 $outChars .= '0';
2836         }
2837
2838         return strrev( $outChars );
2839 }
2840
2841 /**
2842  * Create an object with a given name and an array of construct parameters
2843  * @param $name String
2844  * @param $p Array: parameters
2845  * @deprecated
2846  */
2847 function wfCreateObject( $name, $p ) {
2848         return MWFunction::newObj( $name, $p );
2849 }
2850
2851 function wfHttpOnlySafe() {
2852         global $wgHttpOnlyBlacklist;
2853         if( !version_compare( '5.2', PHP_VERSION, '<' ) ) {
2854                 return false;
2855         }
2856
2857         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2858                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2859                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2860                                 return false;
2861                         }
2862                 }
2863         }
2864
2865         return true;
2866 }
2867
2868 /**
2869  * Initialise php session
2870  */
2871 function wfSetupSession( $sessionId = false ) {
2872         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
2873                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
2874         if( $wgSessionsInMemcached ) {
2875                 require_once( 'MemcachedSessions.php' );
2876         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
2877                 # Only set this if $wgSessionHandler isn't null and session.save_handler
2878                 # hasn't already been set to the desired value (that causes errors)
2879                 ini_set( 'session.save_handler', $wgSessionHandler );
2880         }
2881         $httpOnlySafe = wfHttpOnlySafe();
2882         wfDebugLog( 'cookie',
2883                 'session_set_cookie_params: "' . implode( '", "',
2884                         array(
2885                                 0,
2886                                 $wgCookiePath,
2887                                 $wgCookieDomain,
2888                                 $wgCookieSecure,
2889                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2890         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2891                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2892         } else {
2893                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2894                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2895         }
2896         session_cache_limiter( 'private, must-revalidate' );
2897         if ( $sessionId ) {
2898                 session_id( $sessionId );
2899         }
2900         wfSuppressWarnings();
2901         session_start();
2902         wfRestoreWarnings();
2903 }
2904
2905 /**
2906  * Get an object from the precompiled serialized directory
2907  *
2908  * @return Mixed: the variable on success, false on failure
2909  */
2910 function wfGetPrecompiledData( $name ) {
2911         global $IP;
2912
2913         $file = "$IP/serialized/$name";
2914         if ( file_exists( $file ) ) {
2915                 $blob = file_get_contents( $file );
2916                 if ( $blob ) {
2917                         return unserialize( $blob );
2918                 }
2919         }
2920         return false;
2921 }
2922
2923 function wfGetCaller( $level = 2 ) {
2924         $backtrace = wfDebugBacktrace();
2925         if ( isset( $backtrace[$level] ) ) {
2926                 return wfFormatStackFrame( $backtrace[$level] );
2927         } else {
2928                 $caller = 'unknown';
2929         }
2930         return $caller;
2931 }
2932
2933 /**
2934  * Return a string consisting of callers in the stack. Useful sometimes
2935  * for profiling specific points.
2936  *
2937  * @param $limit The maximum depth of the stack frame to return, or false for
2938  *               the entire stack.
2939  */
2940 function wfGetAllCallers( $limit = 3 ) {
2941         $trace = array_reverse( wfDebugBacktrace() );
2942         if ( !$limit || $limit > count( $trace ) - 1 ) {
2943                 $limit = count( $trace ) - 1;
2944         }
2945         $trace = array_slice( $trace, -$limit - 1, $limit );
2946         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
2947 }
2948
2949 /**
2950  * Return a string representation of frame
2951  */
2952 function wfFormatStackFrame( $frame ) {
2953         return isset( $frame['class'] ) ?
2954                 $frame['class'] . '::' . $frame['function'] :
2955                 $frame['function'];
2956 }
2957
2958 /**
2959  * Get a cache key
2960  */
2961 function wfMemcKey( /*... */ ) {
2962         $args = func_get_args();
2963         $key = wfWikiID() . ':' . implode( ':', $args );
2964         $key = str_replace( ' ', '_', $key );
2965         return $key;
2966 }
2967
2968 /**
2969  * Get a cache key for a foreign DB
2970  */
2971 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2972         $args = array_slice( func_get_args(), 2 );
2973         if ( $prefix ) {
2974                 $key = "$db-$prefix:" . implode( ':', $args );
2975         } else {
2976                 $key = $db . ':' . implode( ':', $args );
2977         }
2978         return $key;
2979 }
2980
2981 /**
2982  * Get an ASCII string identifying this wiki
2983  * This is used as a prefix in memcached keys
2984  */
2985 function wfWikiID() {
2986         global $wgDBprefix, $wgDBname;
2987         if ( $wgDBprefix ) {
2988                 return "$wgDBname-$wgDBprefix";
2989         } else {
2990                 return $wgDBname;
2991         }
2992 }
2993
2994 /**
2995  * Split a wiki ID into DB name and table prefix
2996  */
2997 function wfSplitWikiID( $wiki ) {
2998         $bits = explode( '-', $wiki, 2 );
2999         if ( count( $bits ) < 2 ) {
3000                 $bits[] = '';
3001         }
3002         return $bits;
3003 }
3004
3005 /**
3006  * Get a Database object.
3007  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3008  *            master (for write queries), DB_SLAVE for potentially lagged read
3009  *            queries, or an integer >= 0 for a particular server.
3010  *
3011  * @param $groups Mixed: query groups. An array of group names that this query
3012  *                belongs to. May contain a single string if the query is only
3013  *                in one group.
3014  *
3015  * @param $wiki String: the wiki ID, or false for the current wiki
3016  *
3017  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3018  * will always return the same object, unless the underlying connection or load
3019  * balancer is manually destroyed.
3020  *
3021  * @return DatabaseBase
3022  */
3023 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3024         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3025 }
3026
3027 /**
3028  * Get a load balancer object.
3029  *
3030  * @param $wiki String: wiki ID, or false for the current wiki
3031  * @return LoadBalancer
3032  */
3033 function wfGetLB( $wiki = false ) {
3034         return wfGetLBFactory()->getMainLB( $wiki );
3035 }
3036
3037 /**
3038  * Get the load balancer factory object
3039  * @return LBFactory
3040  */
3041 function &wfGetLBFactory() {
3042         return LBFactory::singleton();
3043 }
3044
3045 /**
3046  * Find a file.
3047  * Shortcut for RepoGroup::singleton()->findFile()
3048  * @param $title String or Title object
3049  * @param $options Associative array of options:
3050  *     time:           requested time for an archived image, or false for the
3051  *                     current version. An image object will be returned which was
3052  *                     created at the specified time.
3053  *
3054  *     ignoreRedirect: If true, do not follow file redirects
3055  *
3056  *     private:        If true, return restricted (deleted) files if the current
3057  *                     user is allowed to view them. Otherwise, such files will not
3058  *                     be found.
3059  *
3060  *     bypassCache:    If true, do not use the process-local cache of File objects
3061  *
3062  * @return File, or false if the file does not exist
3063  */
3064 function wfFindFile( $title, $options = array() ) {
3065         return RepoGroup::singleton()->findFile( $title, $options );
3066 }
3067
3068 /**
3069  * Get an object referring to a locally registered file.
3070  * Returns a valid placeholder object if the file does not exist.
3071  * @param $title Title or String
3072  * @return File, or null if passed an invalid Title
3073  */
3074 function wfLocalFile( $title ) {
3075         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3076 }
3077
3078 /**
3079  * Should low-performance queries be disabled?
3080  *
3081  * @return Boolean
3082  */
3083 function wfQueriesMustScale() {
3084         global $wgMiserMode;
3085         return $wgMiserMode
3086                 || ( SiteStats::pages() > 100000
3087                 && SiteStats::edits() > 1000000
3088                 && SiteStats::users() > 10000 );
3089 }
3090
3091 /**
3092  * Get the path to a specified script file, respecting file
3093  * extensions; this is a wrapper around $wgScriptExtension etc.
3094  *
3095  * @param $script String: script filename, sans extension
3096  * @return String
3097  */
3098 function wfScript( $script = 'index' ) {
3099         global $wgScriptPath, $wgScriptExtension;
3100         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3101 }
3102
3103 /**
3104  * Get the script URL.
3105  *
3106  * @return script URL
3107  */
3108 function wfGetScriptUrl() {
3109         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3110                 #
3111                 # as it was called, minus the query string.
3112                 #
3113                 # Some sites use Apache rewrite rules to handle subdomains,
3114                 # and have PHP set up in a weird way that causes PHP_SELF
3115                 # to contain the rewritten URL instead of the one that the
3116                 # outside world sees.
3117                 #
3118                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3119                 # provides containing the "before" URL.
3120                 return $_SERVER['SCRIPT_NAME'];
3121         } else {
3122                 return $_SERVER['URL'];
3123         }
3124 }
3125
3126 /**
3127  * Convenience function converts boolean values into "true"
3128  * or "false" (string) values
3129  *
3130  * @param $value Boolean
3131  * @return String
3132  */
3133 function wfBoolToStr( $value ) {
3134         return $value ? 'true' : 'false';
3135 }
3136
3137 /**
3138  * Load an extension messages file
3139  * @deprecated in 1.16, warnings in 1.18, remove in 1.20
3140  */
3141 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
3142         wfDeprecated( __FUNCTION__ );
3143 }
3144
3145 /**
3146  * Get a platform-independent path to the null file, e.g.
3147  * /dev/null
3148  *
3149  * @return string
3150  */
3151 function wfGetNull() {
3152         return wfIsWindows()
3153                 ? 'NUL'
3154                 : '/dev/null';
3155 }
3156
3157 /**
3158  * Displays a maxlag error
3159  *
3160  * @param $host String: server that lags the most
3161  * @param $lag Integer: maxlag (actual)
3162  * @param $maxLag Integer: maxlag (requested)
3163  */
3164 function wfMaxlagError( $host, $lag, $maxLag ) {
3165         global $wgShowHostnames;
3166         header( 'HTTP/1.1 503 Service Unavailable' );
3167         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
3168         header( 'X-Database-Lag: ' . intval( $lag ) );
3169         header( 'Content-Type: text/plain' );
3170         if( $wgShowHostnames ) {
3171                 echo "Waiting for $host: $lag seconds lagged\n";
3172         } else {
3173                 echo "Waiting for a database server: $lag seconds lagged\n";
3174         }
3175 }
3176
3177 /**
3178  * Throws a warning that $function is deprecated
3179  * @param $function String
3180  * @return null
3181  */
3182 function wfDeprecated( $function ) {
3183         static $functionsWarned = array();
3184         if ( !isset( $functionsWarned[$function] ) ) {
3185                 $functionsWarned[$function] = true;
3186                 wfWarn( "Use of $function is deprecated.", 2 );
3187         }
3188 }
3189
3190 /**
3191  * Send a warning either to the debug log or in a PHP error depending on
3192  * $wgDevelopmentWarnings
3193  *
3194  * @param $msg String: message to send
3195  * @param $callerOffset Integer: number of itmes to go back in the backtrace to
3196  *        find the correct caller (1 = function calling wfWarn, ...)
3197  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3198  *        is true
3199  */
3200 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3201         $callers = wfDebugBacktrace();
3202         if( isset( $callers[$callerOffset + 1] ) ){
3203                 $callerfunc = $callers[$callerOffset + 1];
3204                 $callerfile = $callers[$callerOffset];
3205                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3206                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3207                 } else {
3208                         $file = '(internal function)';
3209                 }
3210                 $func = '';
3211                 if( isset( $callerfunc['class'] ) ) {
3212                         $func .= $callerfunc['class'] . '::';
3213                 }
3214                 if( isset( $callerfunc['function'] ) ) {
3215                         $func .= $callerfunc['function'];
3216                 }
3217                 $msg .= " [Called from $func in $file]";
3218         }
3219
3220         global $wgDevelopmentWarnings;
3221         if ( $wgDevelopmentWarnings ) {
3222                 trigger_error( $msg, $level );
3223         } else {
3224                 wfDebug( "$msg\n" );
3225         }
3226 }
3227
3228 /**
3229  * Sleep until the worst slave's replication lag is less than or equal to
3230  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
3231  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3232  * a no-op if there are no slaves.
3233  *
3234  * Every time the function has to wait for a slave, it will print a message to
3235  * that effect (and then sleep for a little while), so it's probably not best
3236  * to use this outside maintenance scripts in its present form.
3237  *
3238  * @param $maxLag Integer
3239  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3240  * @return null
3241  */
3242 function wfWaitForSlaves( $maxLag, $wiki = false ) {
3243         if( $maxLag ) {
3244                 $lb = wfGetLB( $wiki );
3245                 list( $host, $lag ) = $lb->getMaxLag( $wiki );
3246                 while( $lag > $maxLag ) {
3247                         wfSuppressWarnings();
3248                         $name = gethostbyaddr( $host );
3249                         wfRestoreWarnings();
3250                         if( $name !== false ) {
3251                                 $host = $name;
3252                         }
3253                         print "Waiting for $host (lagged $lag seconds)...\n";
3254                         sleep( $maxLag );
3255                         list( $host, $lag ) = $lb->getMaxLag();
3256                 }
3257         }
3258 }
3259
3260 /**
3261  * Used to be used for outputting text in the installer/updater
3262  * @deprecated Warnings in 1.19, removal in 1.20
3263  */
3264 function wfOut( $s ) {
3265         global $wgCommandLineMode;
3266         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3267                 echo $s;
3268         } else {
3269                 echo htmlspecialchars( $s );
3270         }
3271         flush();
3272 }
3273
3274 /**
3275  * Count down from $n to zero on the terminal, with a one-second pause
3276  * between showing each number. For use in command-line scripts.
3277  */
3278 function wfCountDown( $n ) {
3279         for ( $i = $n; $i >= 0; $i-- ) {
3280                 if ( $i != $n ) {
3281                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3282                 }
3283                 echo $i;
3284                 flush();
3285                 if ( $i ) {
3286                         sleep( 1 );
3287                 }
3288         }
3289         echo "\n";
3290 }
3291
3292 /**
3293  * Generate a random 32-character hexadecimal token.
3294  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3295  *              characters before hashing.
3296  */
3297 function wfGenerateToken( $salt = '' ) {
3298         $salt = serialize( $salt );
3299         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3300 }
3301
3302 /**
3303  * Replace all invalid characters with -
3304  * @param $name Mixed: filename to process
3305  */
3306 function wfStripIllegalFilenameChars( $name ) {
3307         global $wgIllegalFileChars;
3308         $name = wfBaseName( $name );
3309         $name = preg_replace(
3310                 "/[^" . Title::legalChars() . "]" .
3311                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3312                         "/",
3313                 '-',
3314                 $name
3315         );
3316         return $name;
3317 }
3318
3319 /**
3320  * Insert array into another array after the specified *KEY*
3321  * @param $array Array: The array.
3322  * @param $insert Array: The array to insert.
3323  * @param $after Mixed: The key to insert after
3324  */
3325 function wfArrayInsertAfter( $array, $insert, $after ) {
3326         // Find the offset of the element to insert after.
3327         $keys = array_keys( $array );
3328         $offsetByKey = array_flip( $keys );
3329
3330         $offset = $offsetByKey[$after];
3331
3332         // Insert at the specified offset
3333         $before = array_slice( $array, 0, $offset + 1, true );
3334         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
3335
3336         $output = $before + $insert + $after;
3337
3338         return $output;
3339 }
3340
3341 /* Recursively converts the parameter (an object) to an array with the same data */
3342 function wfObjectToArray( $object, $recursive = true ) {
3343         $array = array();
3344         foreach ( get_object_vars( $object ) as $key => $value ) {
3345                 if ( is_object( $value ) && $recursive ) {
3346                         $value = wfObjectToArray( $value );
3347                 }
3348
3349                 $array[$key] = $value;
3350         }
3351
3352         return $array;
3353 }
3354
3355 /**
3356  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3357  * @return Integer value memory was set to.
3358  */
3359 function wfMemoryLimit() {
3360         global $wgMemoryLimit;
3361         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3362         if( $memlimit != -1 ) {
3363                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3364                 if( $conflimit == -1 ) {
3365                         wfDebug( "Removing PHP's memory limit\n" );
3366                         wfSuppressWarnings();
3367                         ini_set( 'memory_limit', $conflimit );
3368                         wfRestoreWarnings();
3369                         return $conflimit;
3370                 } elseif ( $conflimit > $memlimit ) {
3371                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3372                         wfSuppressWarnings();
3373                         ini_set( 'memory_limit', $conflimit );
3374                         wfRestoreWarnings();
3375                         return $conflimit;
3376                 }
3377         }
3378         return $memlimit;
3379 }
3380
3381 /**
3382  * Converts shorthand byte notation to integer form
3383  * @param $string String
3384  * @return Integer
3385  */
3386 function wfShorthandToInteger( $string = '' ) {
3387         $string = trim( $string );
3388         if( $string === '' ) {
3389                 return -1;
3390         }
3391         $last = $string[strlen( $string ) - 1];
3392         $val = intval( $string );
3393         switch( $last ) {
3394                 case 'g':
3395                 case 'G':
3396                         $val *= 1024;
3397                         // break intentionally missing
3398                 case 'm':
3399                 case 'M':
3400                         $val *= 1024;
3401                         // break intentionally missing
3402                 case 'k':
3403                 case 'K':
3404                         $val *= 1024;
3405         }
3406
3407         return $val;
3408 }
3409
3410 /**
3411  * Get the normalised IETF language tag
3412  * @param $code String: The language code.
3413  * @return $langCode String: The language code which complying with BCP 47 standards.
3414  */
3415 function wfBCP47( $code ) {
3416         $codeSegment = explode( '-', $code );
3417         foreach ( $codeSegment as $segNo => $seg ) {
3418                 if ( count( $codeSegment ) > 0 ) {
3419                         // ISO 3166 country code
3420                         if ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3421                                 $codeBCP[$segNo] = strtoupper( $seg );
3422                         // ISO 15924 script code
3423                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3424                                 $codeBCP[$segNo] = ucfirst( $seg );
3425                         // Use lowercase for other cases
3426                         } else {
3427                                 $codeBCP[$segNo] = strtolower( $seg );
3428                         }
3429                 } else {
3430                 // Use lowercase for single segment
3431                         $codeBCP[$segNo] = strtolower( $seg );
3432                 }
3433         }
3434         $langCode = implode( '-', $codeBCP );
3435         return $langCode;
3436 }
3437
3438 function wfArrayMap( $function, $input ) {
3439         $ret = array_map( $function, $input );
3440         foreach ( $ret as $key => $value ) {
3441                 $taint = istainted( $input[$key] );
3442                 if ( $taint ) {
3443                         taint( $ret[$key], $taint );
3444                 }
3445         }
3446         return $ret;
3447 }