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