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 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /** @codeCoverageIgnore */
  24         function iconv( $from, $to, $string ) {
  25                 return Fallback::iconv( $from, $to, $string );
  26         }
  27 }
  28
  29 if ( !function_exists( 'mb_substr' ) ) {
  30         /** @codeCoverageIgnore */
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::mb_substr( $str, $start, $count );
  33         }
  34
  35         /** @codeCoverageIgnore */
  36         function mb_substr_split_unicode( $str, $splitPos ) {
  37                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  38         }
  39 }
  40
  41 if ( !function_exists( 'mb_strlen' ) ) {
  42         /** @codeCoverageIgnore */
  43         function mb_strlen( $str, $enc = '' ) {
  44                 return Fallback::mb_strlen( $str, $enc );
  45         }
  46 }
  47
  48 if( !function_exists( 'mb_strpos' ) ) {
  49         /** @codeCoverageIgnore */
  50         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  51                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  52         }
  53
  54 }
  55
  56 if( !function_exists( 'mb_strrpos' ) ) {
  57         /** @codeCoverageIgnore */
  58         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  59                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  60         }
  61 }
  62
  63
  64 // Support for Wietse Venema's taint feature
  65 if ( !function_exists( 'istainted' ) ) {
  66         /** @codeCoverageIgnore */
  67         function istainted( $var ) {
  68                 return 0;
  69         }
  70         /** @codeCoverageIgnore */
  71         function taint( $var, $level = 0 ) {}
  72         /** @codeCoverageIgnore */
  73         function untaint( $var, $level = 0 ) {}
  74         define( 'TC_HTML', 1 );
  75         define( 'TC_SHELL', 1 );
  76         define( 'TC_MYSQL', 1 );
  77         define( 'TC_PCRE', 1 );
  78         define( 'TC_SELF', 1 );
  79 }
  80 /// @endcond
  81
  82 /**
  83  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  84  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88 function wfArrayDiff2_cmp( $a, $b ) {
  89         if ( !is_array( $a ) ) {
  90                 return strcmp( $a, $b );
  91         } elseif ( count( $a ) !== count( $b ) ) {
  92                 return count( $a ) < count( $b ) ? -1 : 1;
  93         } else {
  94                 reset( $a );
  95                 reset( $b );
  96                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
  97                         $cmp = strcmp( $valueA, $valueB );
  98                         if ( $cmp !== 0 ) {
  99                                 return $cmp;
 100                         }
 101                 }
 102                 return 0;
 103         }
 104 }
 105
 106 /**
 107  * Array lookup
 108  * Returns an array where the values in the first array are replaced by the
 109  * values in the second array with the corresponding keys
 110  *
 111  * @param $a Array
 112  * @param $b Array
 113  * @return array
 114  */
 115 function wfArrayLookup( $a, $b ) {
 116         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 117 }
 118
 119 /**
 120  * Appends to second array if $value differs from that in $default
 121  *
 122  * @param $key String|Int
 123  * @param $value Mixed
 124  * @param $default Mixed
 125  * @param $changed Array to alter
 126  */
 127 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 128         if ( is_null( $changed ) ) {
 129                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 130         }
 131         if ( $default[$key] !== $value ) {
 132                 $changed[$key] = $value;
 133         }
 134 }
 135
 136 /**
 137  * Backwards array plus for people who haven't bothered to read the PHP manual
 138  * XXX: will not darn your socks for you.
 139  *
 140  * @param $array1 Array
 141  * @param [$array2, [...]] Arrays
 142  * @return Array
 143  */
 144 function wfArrayMerge( $array1/* ... */ ) {
 145         $args = func_get_args();
 146         $args = array_reverse( $args, true );
 147         $out = array();
 148         foreach ( $args as $arg ) {
 149                 $out += $arg;
 150         }
 151         return $out;
 152 }
 153
 154 /**
 155  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 156  * e.g.
 157  *      wfMergeErrorArrays(
 158  *              array( array( 'x' ) ),
 159  *              array( array( 'x', '2' ) ),
 160  *              array( array( 'x' ) ),
 161  *              array( array( 'y') )
 162  *      );
 163  * returns:
 164  *              array(
 165  *              array( 'x', '2' ),
 166  *              array( 'x' ),
 167  *              array( 'y' )
 168  *      )
 169  * @param varargs
 170  * @return Array
 171  */
 172 function wfMergeErrorArrays( /*...*/ ) {
 173         $args = func_get_args();
 174         $out = array();
 175         foreach ( $args as $errors ) {
 176                 foreach ( $errors as $params ) {
 177                         # @todo FIXME: Sometimes get nested arrays for $params,
 178                         # which leads to E_NOTICEs
 179                         $spec = implode( "\t", $params );
 180                         $out[$spec] = $params;
 181                 }
 182         }
 183         return array_values( $out );
 184 }
 185
 186 /**
 187  * Insert array into another array after the specified *KEY*
 188  *
 189  * @param $array Array: The array.
 190  * @param $insert Array: The array to insert.
 191  * @param $after Mixed: The key to insert after
 192  * @return Array
 193  */
 194 function wfArrayInsertAfter( $array, $insert, $after ) {
 195         // Find the offset of the element to insert after.
 196         $keys = array_keys( $array );
 197         $offsetByKey = array_flip( $keys );
 198
 199         $offset = $offsetByKey[$after];
 200
 201         // Insert at the specified offset
 202         $before = array_slice( $array, 0, $offset + 1, true );
 203         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 204
 205         $output = $before + $insert + $after;
 206
 207         return $output;
 208 }
 209
 210 /**
 211  * Recursively converts the parameter (an object) to an array with the same data
 212  *
 213  * @param $objOrArray Object|Array
 214  * @param $recursive Bool
 215  * @return Array
 216  */
 217 function wfObjectToArray( $objOrArray, $recursive = true ) {
 218         $array = array();
 219         if( is_object( $objOrArray ) ) {
 220                 $objOrArray = get_object_vars( $objOrArray );
 221         }
 222         foreach ( $objOrArray as $key => $value ) {
 223                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 224                         $value = wfObjectToArray( $value );
 225                 }
 226
 227                 $array[$key] = $value;
 228         }
 229
 230         return $array;
 231 }
 232
 233 /**
 234  * Wrapper around array_map() which also taints variables
 235  *
 236  * @param  $function Callback
 237  * @param  $input Array
 238  * @return Array
 239  */
 240 function wfArrayMap( $function, $input ) {
 241         $ret = array_map( $function, $input );
 242         foreach ( $ret as $key => $value ) {
 243                 $taint = istainted( $input[$key] );
 244                 if ( $taint ) {
 245                         taint( $ret[$key], $taint );
 246                 }
 247         }
 248         return $ret;
 249 }
 250
 251 /**
 252  * Get a random decimal value between 0 and 1, in a way
 253  * not likely to give duplicate values for any realistic
 254  * number of articles.
 255  *
 256  * @return string
 257  */
 258 function wfRandom() {
 259         # The maximum random value is "only" 2^31-1, so get two random
 260         # values to reduce the chance of dupes
 261         $max = mt_getrandmax() + 1;
 262         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 263                 / $max / $max, 12, '.', '' );
 264         return $rand;
 265 }
 266
 267 /**
 268  * We want some things to be included as literal characters in our title URLs
 269  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 270  * all of the following should be safe:
 271  *
 272  * ;:@&=$-_.+!*'(),
 273  *
 274  * But + is not safe because it's used to indicate a space; &= are only safe in
 275  * paths and not in queries (and we don't distinguish here); ' seems kind of
 276  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 277  * is reserved, we don't care.  So the list we unescape is:
 278  *
 279  * ;:@$!*(),/
 280  *
 281  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 282  * so no fancy : for IIS7.
 283  *
 284  * %2F in the page titles seems to fatally break for some reason.
 285  *
 286  * @param $s String:
 287  * @return string
 288 */
 289 function wfUrlencode( $s ) {
 290         static $needle;
 291         if ( is_null( $needle ) ) {
 292                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 293                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 294                         $needle[] = '%3A';
 295                 }
 296         }
 297
 298         $s = urlencode( $s );
 299         $s = str_ireplace(
 300                 $needle,
 301                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 302                 $s
 303         );
 304
 305         return $s;
 306 }
 307
 308 /**
 309  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 310  * In normal operation this is a NOP.
 311  *
 312  * Controlling globals:
 313  * $wgDebugLogFile - points to the log file
 314  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 315  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 316  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 317  *
 318  * @param $text String
 319  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 320  */
 321 function wfDebug( $text, $logonly = false ) {
 322         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 323         global $wgDebugLogPrefix, $wgShowDebug;
 324
 325         static $cache = array(); // Cache of unoutputted messages
 326         $text = wfDebugTimer() . $text;
 327
 328         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 329         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 330                 return;
 331         }
 332
 333         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 334                 $cache[] = $text;
 335
 336                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 337                         // add the message and any cached messages to the output
 338                         array_map( array( $wgOut, 'debug' ), $cache );
 339                         $cache = array();
 340                 }
 341         }
 342         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 343                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 344                         # Strip unprintables; they can switch terminal modes when binary data
 345                         # gets dumped, which is pretty annoying.
 346                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 347                         $text = $wgDebugLogPrefix . $text;
 348                         wfErrorLog( $text, $wgDebugLogFile );
 349                 }
 350         }
 351 }
 352
 353 /**
 354  * Get microsecond timestamps for debug logs
 355  *
 356  * @return string
 357  */
 358 function wfDebugTimer() {
 359         global $wgDebugTimestamps;
 360         if ( !$wgDebugTimestamps ) {
 361                 return '';
 362         }
 363         static $start = null;
 364
 365         if ( $start === null ) {
 366                 $start = microtime( true );
 367                 $prefix = "\n$start";
 368         } else {
 369                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 370         }
 371
 372         return $prefix . '  ';
 373 }
 374
 375 /**
 376  * Send a line giving PHP memory usage.
 377  *
 378  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 379  */
 380 function wfDebugMem( $exact = false ) {
 381         $mem = memory_get_usage();
 382         if( !$exact ) {
 383                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 384         } else {
 385                 $mem .= ' bytes';
 386         }
 387         wfDebug( "Memory usage: $mem\n" );
 388 }
 389
 390 /**
 391  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 392  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 393  *
 394  * @param $logGroup String
 395  * @param $text String
 396  * @param $public Bool: whether to log the event in the public log if no private
 397  *                     log file is specified, (default true)
 398  */
 399 function wfDebugLog( $logGroup, $text, $public = true ) {
 400         global $wgDebugLogGroups, $wgShowHostnames;
 401         $text = trim( $text ) . "\n";
 402         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 403                 $time = wfTimestamp( TS_DB );
 404                 $wiki = wfWikiID();
 405                 if ( $wgShowHostnames ) {
 406                         $host = wfHostname();
 407                 } else {
 408                         $host = '';
 409                 }
 410                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 411                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 412                 }
 413         } elseif ( $public === true ) {
 414                 wfDebug( $text, true );
 415         }
 416 }
 417
 418 /**
 419  * Log for database errors
 420  *
 421  * @param $text String: database error message.
 422  */
 423 function wfLogDBError( $text ) {
 424         global $wgDBerrorLog, $wgDBname;
 425         if ( $wgDBerrorLog ) {
 426                 $host = trim(`hostname`);
 427                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 428                 wfErrorLog( $text, $wgDBerrorLog );
 429         }
 430 }
 431
 432 /**
 433  * Log to a file without getting "file size exceeded" signals.
 434  *
 435  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 436  * send lines to the specified port, prefixed by the specified prefix and a space.
 437  *
 438  * @param $text String
 439  * @param $file String filename
 440  */
 441 function wfErrorLog( $text, $file ) {
 442         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 443                 # Needs the sockets extension
 444                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 445                         // IPv6 bracketed host
 446                         $host = $m[2];
 447                         $port = intval( $m[3] );
 448                         $prefix = isset( $m[4] ) ? $m[4] : false;
 449                         $domain = AF_INET6;
 450                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 451                         $host = $m[2];
 452                         if ( !IP::isIPv4( $host ) ) {
 453                                 $host = gethostbyname( $host );
 454                         }
 455                         $port = intval( $m[3] );
 456                         $prefix = isset( $m[4] ) ? $m[4] : false;
 457                         $domain = AF_INET;
 458                 } else {
 459                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 460                 }
 461
 462                 // Clean it up for the multiplexer
 463                 if ( strval( $prefix ) !== '' ) {
 464                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 465
 466                         // Limit to 64KB
 467                         if ( strlen( $text ) > 65534 ) {
 468                                 $text = substr( $text, 0, 65534 );
 469                         }
 470
 471                         if ( substr( $text, -1 ) != "\n" ) {
 472                                 $text .= "\n";
 473                         }
 474                 } elseif ( strlen( $text ) > 65535 ) {
 475                         $text = substr( $text, 0, 65535 );
 476                 }
 477
 478                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 479                 if ( !$sock ) {
 480                         return;
 481                 }
 482                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 483                 socket_close( $sock );
 484         } else {
 485                 wfSuppressWarnings();
 486                 $exists = file_exists( $file );
 487                 $size = $exists ? filesize( $file ) : false;
 488                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 489                         file_put_contents( $file, $text, FILE_APPEND );
 490                 }
 491                 wfRestoreWarnings();
 492         }
 493 }
 494
 495 /**
 496  * @todo document
 497  */
 498 function wfLogProfilingData() {
 499         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 500         global $wgProfileLimit, $wgUser;
 501
 502         $profiler = Profiler::instance();
 503
 504         # Profiling must actually be enabled...
 505         if ( $profiler->isStub() ) {
 506                 return;
 507         }
 508
 509         // Get total page request time and only show pages that longer than
 510         // $wgProfileLimit time (default is 0)
 511         $now = wfTime();
 512         $elapsed = $now - $wgRequestTime;
 513         if ( $elapsed <= $wgProfileLimit ) {
 514                 return;
 515         }
 516
 517         $profiler->logData();
 518
 519         // Check whether this should be logged in the debug file.
 520         if ( $wgDebugLogFile == '' || ( $wgRequest->getVal( 'action' ) == 'raw' && !$wgDebugRawPage ) ) {
 521                 return;
 522         }
 523
 524         $forward = '';
 525         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 526                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 527         }
 528         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 529                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 530         }
 531         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 532                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 533         }
 534         if ( $forward ) {
 535                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 536         }
 537         // Don't load $wgUser at this late stage just for statistics purposes
 538         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 539         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 540                 $forward .= ' anon';
 541         }
 542         $log = sprintf( "%s\t%04.3f\t%s\n",
 543                 gmdate( 'YmdHis' ), $elapsed,
 544                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 545
 546         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 547 }
 548
 549 /**
 550  * Check if the wiki read-only lock file is present. This can be used to lock
 551  * off editing functions, but doesn't guarantee that the database will not be
 552  * modified.
 553  *
 554  * @return bool
 555  */
 556 function wfReadOnly() {
 557         global $wgReadOnlyFile, $wgReadOnly;
 558
 559         if ( !is_null( $wgReadOnly ) ) {
 560                 return (bool)$wgReadOnly;
 561         }
 562         if ( $wgReadOnlyFile == '' ) {
 563                 return false;
 564         }
 565         // Set $wgReadOnly for faster access next time
 566         if ( is_file( $wgReadOnlyFile ) ) {
 567                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 568         } else {
 569                 $wgReadOnly = false;
 570         }
 571         return (bool)$wgReadOnly;
 572 }
 573
 574 function wfReadOnlyReason() {
 575         global $wgReadOnly;
 576         wfReadOnly();
 577         return $wgReadOnly;
 578 }
 579
 580 /**
 581  * Return a Language object from $langcode
 582  *
 583  * @param $langcode Mixed: either:
 584  *                  - a Language object
 585  *                  - code of the language to get the message for, if it is
 586  *                    a valid code create a language for that language, if
 587  *                    it is a string but not a valid code then make a basic
 588  *                    language object
 589  *                  - a boolean: if it's false then use the current users
 590  *                    language (as a fallback for the old parameter
 591  *                    functionality), or if it is true then use the wikis
 592  * @return Language object
 593  */
 594 function wfGetLangObj( $langcode = false ) {
 595         # Identify which language to get or create a language object for.
 596         # Using is_object here due to Stub objects.
 597         if( is_object( $langcode ) ) {
 598                 # Great, we already have the object (hopefully)!
 599                 return $langcode;
 600         }
 601
 602         global $wgContLang, $wgLanguageCode;
 603         if( $langcode === true || $langcode === $wgLanguageCode ) {
 604                 # $langcode is the language code of the wikis content language object.
 605                 # or it is a boolean and value is true
 606                 return $wgContLang;
 607         }
 608
 609         global $wgLang;
 610         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 611                 # $langcode is the language code of user language object.
 612                 # or it was a boolean and value is false
 613                 return $wgLang;
 614         }
 615
 616         $validCodes = array_keys( Language::getLanguageNames() );
 617         if( in_array( $langcode, $validCodes ) ) {
 618                 # $langcode corresponds to a valid language.
 619                 return Language::factory( $langcode );
 620         }
 621
 622         # $langcode is a string, but not a valid language code; use content language.
 623         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 624         return $wgContLang;
 625 }
 626
 627 /**
 628  * Use this instead of $wgContLang, when working with user interface.
 629  * User interface is currently hard coded according to wiki content language
 630  * in many ways, especially regarding to text direction. There is lots stuff
 631  * to fix, hence this function to keep the old behaviour unless the global
 632  * $wgBetterDirectionality is enabled (or removed when everything works).
 633  *
 634  * @return Language
 635  */
 636 function wfUILang() {
 637         global $wgBetterDirectionality;
 638         return wfGetLangObj( !$wgBetterDirectionality );
 639 }
 640
 641 /**
 642  * This is the new function for getting translated interface messages.
 643  * See the Message class for documentation how to use them.
 644  * The intention is that this function replaces all old wfMsg* functions.
 645  * @param $key \string Message key.
 646  * Varargs: normal message parameters.
 647  * @return Message
 648  * @since 1.17
 649  */
 650 function wfMessage( $key /*...*/) {
 651         $params = func_get_args();
 652         array_shift( $params );
 653         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 654                 $params = $params[0];
 655         }
 656         return new Message( $key, $params );
 657 }
 658
 659 /**
 660  * This function accepts multiple message keys and returns a message instance
 661  * for the first message which is non-empty. If all messages are empty then an
 662  * instance of the first message key is returned.
 663  * @param varargs: message keys
 664  * @return Message
 665  * @since 1.18
 666  */
 667 function wfMessageFallback( /*...*/ ) {
 668         $args = func_get_args();
 669         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
 670 }
 671
 672 /**
 673  * Get a message from anywhere, for the current user language.
 674  *
 675  * Use wfMsgForContent() instead if the message should NOT
 676  * change depending on the user preferences.
 677  *
 678  * @param $key String: lookup key for the message, usually
 679  *    defined in languages/Language.php
 680  *
 681  * This function also takes extra optional parameters (not
 682  * shown in the function definition), which can be used to
 683  * insert variable text into the predefined message.
 684  * @return String
 685  */
 686 function wfMsg( $key ) {
 687         $args = func_get_args();
 688         array_shift( $args );
 689         return wfMsgReal( $key, $args, true );
 690 }
 691
 692 /**
 693  * Same as above except doesn't transform the message
 694  *
 695  * @param $key String
 696  * @return String
 697  */
 698 function wfMsgNoTrans( $key ) {
 699         $args = func_get_args();
 700         array_shift( $args );
 701         return wfMsgReal( $key, $args, true, false, false );
 702 }
 703
 704 /**
 705  * Get a message from anywhere, for the current global language
 706  * set with $wgLanguageCode.
 707  *
 708  * Use this if the message should NOT change dependent on the
 709  * language set in the user's preferences. This is the case for
 710  * most text written into logs, as well as link targets (such as
 711  * the name of the copyright policy page). Link titles, on the
 712  * other hand, should be shown in the UI language.
 713  *
 714  * Note that MediaWiki allows users to change the user interface
 715  * language in their preferences, but a single installation
 716  * typically only contains content in one language.
 717  *
 718  * Be wary of this distinction: If you use wfMsg() where you should
 719  * use wfMsgForContent(), a user of the software may have to
 720  * customize potentially hundreds of messages in
 721  * order to, e.g., fix a link in every possible language.
 722  *
 723  * @param $key String: lookup key for the message, usually
 724  *     defined in languages/Language.php
 725  * @return String
 726  */
 727 function wfMsgForContent( $key ) {
 728         global $wgForceUIMsgAsContentMsg;
 729         $args = func_get_args();
 730         array_shift( $args );
 731         $forcontent = true;
 732         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 733                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 734         {
 735                 $forcontent = false;
 736         }
 737         return wfMsgReal( $key, $args, true, $forcontent );
 738 }
 739
 740 /**
 741  * Same as above except doesn't transform the message
 742  *
 743  * @param $key String
 744  * @return String
 745  */
 746 function wfMsgForContentNoTrans( $key ) {
 747         global $wgForceUIMsgAsContentMsg;
 748         $args = func_get_args();
 749         array_shift( $args );
 750         $forcontent = true;
 751         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 752                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 753         {
 754                 $forcontent = false;
 755         }
 756         return wfMsgReal( $key, $args, true, $forcontent, false );
 757 }
 758
 759 /**
 760  * Get a message from the language file, for the UI elements
 761  *
 762  * @deprecated since 1.18; use wfMessage()
 763  */
 764 function wfMsgNoDB( $key ) {
 765         wfDeprecated( __FUNCTION__ );
 766         $args = func_get_args();
 767         array_shift( $args );
 768         return wfMsgReal( $key, $args, false );
 769 }
 770
 771 /**
 772  * Get a message from the language file, for the content
 773  *
 774  * @deprecated since 1.18; use wfMessage()
 775  */
 776 function wfMsgNoDBForContent( $key ) {
 777         wfDeprecated( __FUNCTION__ );
 778         global $wgForceUIMsgAsContentMsg;
 779         $args = func_get_args();
 780         array_shift( $args );
 781         $forcontent = true;
 782         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 783                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 784         {
 785                 $forcontent = false;
 786         }
 787         return wfMsgReal( $key, $args, false, $forcontent );
 788 }
 789
 790
 791 /**
 792  * Really get a message
 793  *
 794  * @param $key String: key to get.
 795  * @param $args
 796  * @param $useDB Boolean
 797  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 798  * @param $transform Boolean: Whether or not to transform the message.
 799  * @return String: the requested message.
 800  */
 801 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 802         wfProfileIn( __METHOD__ );
 803         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 804         $message = wfMsgReplaceArgs( $message, $args );
 805         wfProfileOut( __METHOD__ );
 806         return $message;
 807 }
 808
 809 /**
 810  * This function provides the message source for messages to be edited which are *not* stored in the database.
 811  *
 812  * @deprecated since 1.18; use wfMessage()
 813  * @param $key String
 814  */
 815 function wfMsgWeirdKey( $key ) {
 816         wfDeprecated( __FUNCTION__ );
 817         $source = wfMsgGetKey( $key, false, true, false );
 818         if ( wfEmptyMsg( $key ) ) {
 819                 return '';
 820         } else {
 821                 return $source;
 822         }
 823 }
 824
 825 /**
 826  * Fetch a message string value, but don't replace any keys yet.
 827  *
 828  * @param $key String
 829  * @param $useDB Bool
 830  * @param $langCode String: Code of the language to get the message for, or
 831  *                  behaves as a content language switch if it is a boolean.
 832  * @param $transform Boolean: whether to parse magic words, etc.
 833  * @return string
 834  */
 835 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 836         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 837
 838         $cache = MessageCache::singleton();
 839         $message = $cache->get( $key, $useDB, $langCode );
 840         if( $message === false ) {
 841                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 842         } elseif ( $transform ) {
 843                 $message = $cache->transform( $message );
 844         }
 845         return $message;
 846 }
 847
 848 /**
 849  * Replace message parameter keys on the given formatted output.
 850  *
 851  * @param $message String
 852  * @param $args Array
 853  * @return string
 854  * @private
 855  */
 856 function wfMsgReplaceArgs( $message, $args ) {
 857         # Fix windows line-endings
 858         # Some messages are split with explode("\n", $msg)
 859         $message = str_replace( "\r", '', $message );
 860
 861         // Replace arguments
 862         if ( count( $args ) ) {
 863                 if ( is_array( $args[0] ) ) {
 864                         $args = array_values( $args[0] );
 865                 }
 866                 $replacementKeys = array();
 867                 foreach( $args as $n => $param ) {
 868                         $replacementKeys['$' . ( $n + 1 )] = $param;
 869                 }
 870                 $message = strtr( $message, $replacementKeys );
 871         }
 872
 873         return $message;
 874 }
 875
 876 /**
 877  * Return an HTML-escaped version of a message.
 878  * Parameter replacements, if any, are done *after* the HTML-escaping,
 879  * so parameters may contain HTML (eg links or form controls). Be sure
 880  * to pre-escape them if you really do want plaintext, or just wrap
 881  * the whole thing in htmlspecialchars().
 882  *
 883  * @param $key String
 884  * @param string ... parameters
 885  * @return string
 886  */
 887 function wfMsgHtml( $key ) {
 888         $args = func_get_args();
 889         array_shift( $args );
 890         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 891 }
 892
 893 /**
 894  * Return an HTML version of message
 895  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 896  * so parameters may contain HTML (eg links or form controls). Be sure
 897  * to pre-escape them if you really do want plaintext, or just wrap
 898  * the whole thing in htmlspecialchars().
 899  *
 900  * @param $key String
 901  * @param string ... parameters
 902  * @return string
 903  */
 904 function wfMsgWikiHtml( $key ) {
 905         $args = func_get_args();
 906         array_shift( $args );
 907         return wfMsgReplaceArgs(
 908                 MessageCache::singleton()->parse( wfMsgGetKey( $key, true ), null, /* can't be set to false */ true )->getText(),
 909                 $args );
 910 }
 911
 912 /**
 913  * Returns message in the requested format
 914  * @param $key String: key of the message
 915  * @param $options Array: processing rules. Can take the following options:
 916  *   <i>parse</i>: parses wikitext to HTML
 917  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 918  *       p's added by parser or tidy
 919  *   <i>escape</i>: filters message through htmlspecialchars
 920  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 921  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 922  *   <i>parsemag</i>: transform the message using magic phrases
 923  *   <i>content</i>: fetch message for content language instead of interface
 924  * Also can accept a single associative argument, of the form 'language' => 'xx':
 925  *   <i>language</i>: Language object or language code to fetch message for
 926  *       (overriden by <i>content</i>).
 927  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 928  *
 929  * @return String
 930  */
 931 function wfMsgExt( $key, $options ) {
 932         $args = func_get_args();
 933         array_shift( $args );
 934         array_shift( $args );
 935         $options = (array)$options;
 936
 937         foreach( $options as $arrayKey => $option ) {
 938                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 939                         # An unknown index, neither numeric nor "language"
 940                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 941                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 942                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 943                 'replaceafter', 'parsemag', 'content' ) ) ) {
 944                         # A numeric index with unknown value
 945                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 946                 }
 947         }
 948
 949         if( in_array( 'content', $options, true ) ) {
 950                 $forContent = true;
 951                 $langCode = true;
 952                 $langCodeObj = null;
 953         } elseif( array_key_exists( 'language', $options ) ) {
 954                 $forContent = false;
 955                 $langCode = wfGetLangObj( $options['language'] );
 956                 $langCodeObj = $langCode;
 957         } else {
 958                 $forContent = false;
 959                 $langCode = false;
 960                 $langCodeObj = null;
 961         }
 962
 963         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 964
 965         if( !in_array( 'replaceafter', $options, true ) ) {
 966                 $string = wfMsgReplaceArgs( $string, $args );
 967         }
 968
 969         $messageCache = MessageCache::singleton();
 970         if( in_array( 'parse', $options, true ) ) {
 971                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
 972         } elseif ( in_array( 'parseinline', $options, true ) ) {
 973                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
 974                 $m = array();
 975                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 976                         $string = $m[1];
 977                 }
 978         } elseif ( in_array( 'parsemag', $options, true ) ) {
 979                 $string = $messageCache->transform( $string,
 980                                 !$forContent, $langCodeObj );
 981         }
 982
 983         if ( in_array( 'escape', $options, true ) ) {
 984                 $string = htmlspecialchars ( $string );
 985         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 986                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 987         }
 988
 989         if( in_array( 'replaceafter', $options, true ) ) {
 990                 $string = wfMsgReplaceArgs( $string, $args );
 991         }
 992
 993         return $string;
 994 }
 995
 996 /**
 997  * Since wfMsg() and co suck, they don't return false if the message key they
 998  * looked up didn't exist but a XHTML string, this function checks for the
 999  * nonexistance of messages by checking the MessageCache::get() result directly.
1000  *
1001  * @param $key      String: the message key looked up
1002  * @return Boolean True if the message *doesn't* exist.
1003  */
1004 function wfEmptyMsg( $key ) {
1005         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1006 }
1007
1008 /**
1009  * Print an error message and die, returning nonzero to the shell if any.  Plain die()
1010  * fails to return nonzero to the shell if you pass a string.  Entry points may customise
1011  * this function to return a prettier error message, but implementations must not assume
1012  * access to any of the usual MediaWiki infrastructure (AutoLoader, localisation, database,
1013  * etc).  This should not be called directly once $wgFullyInitialised is set; instead,
1014  * throw an exception and let Exception.php handle whether or not it's possible to show
1015  * a prettier error.
1016  *
1017  * @param $msg String
1018  */
1019 if( !function_exists( 'wfDie' ) ){
1020         function wfDie( $msg = '' ) {
1021                 echo $msg;
1022                 die( 1 );
1023         }
1024 }
1025
1026 /**
1027  * Throw a debugging exception. This function previously once exited the process,
1028  * but now throws an exception instead, with similar results.
1029  *
1030  * @param $msg String: message shown when dieing.
1031  */
1032 function wfDebugDieBacktrace( $msg = '' ) {
1033         throw new MWException( $msg );
1034 }
1035
1036 /**
1037  * Fetch server name for use in error reporting etc.
1038  * Use real server name if available, so we know which machine
1039  * in a server farm generated the current page.
1040  *
1041  * @return string
1042  */
1043 function wfHostname() {
1044         static $host;
1045         if ( is_null( $host ) ) {
1046                 if ( function_exists( 'posix_uname' ) ) {
1047                         // This function not present on Windows
1048                         $uname = @posix_uname();
1049                 } else {
1050                         $uname = false;
1051                 }
1052                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1053                         $host = $uname['nodename'];
1054                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1055                         # Windows computer name
1056                         $host = getenv( 'COMPUTERNAME' );
1057                 } else {
1058                         # This may be a virtual server.
1059                         $host = $_SERVER['SERVER_NAME'];
1060                 }
1061         }
1062         return $host;
1063 }
1064
1065 /**
1066  * Returns a HTML comment with the elapsed time since request.
1067  * This method has no side effects.
1068  *
1069  * @return string
1070  */
1071 function wfReportTime() {
1072         global $wgRequestTime, $wgShowHostnames;
1073
1074         $now = wfTime();
1075         $elapsed = $now - $wgRequestTime;
1076
1077         return $wgShowHostnames
1078                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1079                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1080 }
1081
1082 /**
1083  * Safety wrapper for debug_backtrace().
1084  *
1085  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1086  * murky circumstances, which may be triggered in part by stub objects
1087  * or other fancy talkin'.
1088  *
1089  * Will return an empty array if Zend Optimizer is detected or if
1090  * debug_backtrace is disabled, otherwise the output from
1091  * debug_backtrace() (trimmed).
1092  *
1093  * @return array of backtrace information
1094  */
1095 function wfDebugBacktrace() {
1096         static $disabled = null;
1097
1098         if( extension_loaded( 'Zend Optimizer' ) ) {
1099                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1100                 return array();
1101         }
1102
1103         if ( is_null( $disabled ) ) {
1104                 $disabled = false;
1105                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1106                 $functions = array_map( 'trim', $functions );
1107                 $functions = array_map( 'strtolower', $functions );
1108                 if ( in_array( 'debug_backtrace', $functions ) ) {
1109                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1110                         $disabled = true;
1111                 }
1112         }
1113         if ( $disabled ) {
1114                 return array();
1115         }
1116
1117         return array_slice( debug_backtrace(), 1 );
1118 }
1119
1120 /**
1121  * Get a debug backtrace as a string
1122  *
1123  * @return string
1124  */
1125 function wfBacktrace() {
1126         global $wgCommandLineMode;
1127
1128         if ( $wgCommandLineMode ) {
1129                 $msg = '';
1130         } else {
1131                 $msg = "<ul>\n";
1132         }
1133         $backtrace = wfDebugBacktrace();
1134         foreach( $backtrace as $call ) {
1135                 if( isset( $call['file'] ) ) {
1136                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1137                         $file = $f[count( $f ) - 1];
1138                 } else {
1139                         $file = '-';
1140                 }
1141                 if( isset( $call['line'] ) ) {
1142                         $line = $call['line'];
1143                 } else {
1144                         $line = '-';
1145                 }
1146                 if ( $wgCommandLineMode ) {
1147                         $msg .= "$file line $line calls ";
1148                 } else {
1149                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1150                 }
1151                 if( !empty( $call['class'] ) ) {
1152                         $msg .= $call['class'] . '::';
1153                 }
1154                 $msg .= $call['function'] . '()';
1155
1156                 if ( $wgCommandLineMode ) {
1157                         $msg .= "\n";
1158                 } else {
1159                         $msg .= "</li>\n";
1160                 }
1161         }
1162         if ( $wgCommandLineMode ) {
1163                 $msg .= "\n";
1164         } else {
1165                 $msg .= "</ul>\n";
1166         }
1167
1168         return $msg;
1169 }
1170
1171 /**
1172  * Get the name of the function which called this function
1173  *
1174  * @param $level Int
1175  * @return Bool|string
1176  */
1177 function wfGetCaller( $level = 2 ) {
1178         $backtrace = wfDebugBacktrace();
1179         if ( isset( $backtrace[$level] ) ) {
1180                 return wfFormatStackFrame( $backtrace[$level] );
1181         } else {
1182                 $caller = 'unknown';
1183         }
1184         return $caller;
1185 }
1186
1187 /**
1188  * Return a string consisting of callers in the stack. Useful sometimes
1189  * for profiling specific points.
1190  *
1191  * @param $limit The maximum depth of the stack frame to return, or false for
1192  *               the entire stack.
1193  * @return String
1194  */
1195 function wfGetAllCallers( $limit = 3 ) {
1196         $trace = array_reverse( wfDebugBacktrace() );
1197         if ( !$limit || $limit > count( $trace ) - 1 ) {
1198                 $limit = count( $trace ) - 1;
1199         }
1200         $trace = array_slice( $trace, -$limit - 1, $limit );
1201         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1202 }
1203
1204 /**
1205  * Return a string representation of frame
1206  *
1207  * @param $frame Array
1208  * @return Bool
1209  */
1210 function wfFormatStackFrame( $frame ) {
1211         return isset( $frame['class'] ) ?
1212                 $frame['class'] . '::' . $frame['function'] :
1213                 $frame['function'];
1214 }
1215
1216
1217 /* Some generic result counters, pulled out of SearchEngine */
1218
1219
1220 /**
1221  * @todo document
1222  *
1223  * @param $offset Int
1224  * @param $limit Int
1225  * @return String
1226  */
1227 function wfShowingResults( $offset, $limit ) {
1228         global $wgLang;
1229         return wfMsgExt(
1230                 'showingresults',
1231                 array( 'parseinline' ),
1232                 $wgLang->formatNum( $limit ),
1233                 $wgLang->formatNum( $offset + 1 )
1234         );
1235 }
1236
1237 /**
1238  * @todo document
1239  *
1240  * @param $offset Int
1241  * @param $limit Int
1242  * @param $num Int
1243  * @return String
1244  */
1245 function wfShowingResultsNum( $offset, $limit, $num ) {
1246         global $wgLang;
1247         return wfMsgExt(
1248                 'showingresultsnum',
1249                 array( 'parseinline' ),
1250                 $wgLang->formatNum( $limit ),
1251                 $wgLang->formatNum( $offset + 1 ),
1252                 $wgLang->formatNum( $num )
1253         );
1254 }
1255
1256 /**
1257  * Generate (prev x| next x) (20|50|100...) type links for paging
1258  *
1259  * @param $offset String
1260  * @param $limit Integer
1261  * @param $link String
1262  * @param $query String: optional URL query parameter string
1263  * @param $atend Bool: optional param for specified if this is the last page
1264  * @return String
1265  */
1266 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1267         global $wgLang;
1268         $fmtLimit = $wgLang->formatNum( $limit );
1269         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1270         # Get prev/next link display text
1271         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1272         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1273         # Get prev/next link title text
1274         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1275         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1276         # Fetch the title object
1277         if( is_object( $link ) ) {
1278                 $title =& $link;
1279         } else {
1280                 $title = Title::newFromText( $link );
1281                 if( is_null( $title ) ) {
1282                         return false;
1283                 }
1284         }
1285         # Make 'previous' link
1286         if( 0 != $offset ) {
1287                 $po = $offset - $limit;
1288                 $po = max( $po, 0 );
1289                 $q = "limit={$limit}&offset={$po}";
1290                 if( $query != '' ) {
1291                         $q .= '&' . $query;
1292                 }
1293                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1294         } else {
1295                 $plink = $prev;
1296         }
1297         # Make 'next' link
1298         $no = $offset + $limit;
1299         $q = "limit={$limit}&offset={$no}";
1300         if( $query != '' ) {
1301                 $q .= '&' . $query;
1302         }
1303         if( $atend ) {
1304                 $nlink = $next;
1305         } else {
1306                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1307         }
1308         # Make links to set number of items per page
1309         $nums = $wgLang->pipeList( array(
1310                 wfNumLink( $offset, 20, $title, $query ),
1311                 wfNumLink( $offset, 50, $title, $query ),
1312                 wfNumLink( $offset, 100, $title, $query ),
1313                 wfNumLink( $offset, 250, $title, $query ),
1314                 wfNumLink( $offset, 500, $title, $query )
1315         ) );
1316         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1317 }
1318
1319 /**
1320  * Generate links for (20|50|100...) items-per-page links
1321  *
1322  * @param $offset String
1323  * @param $limit Integer
1324  * @param $title Title
1325  * @param $query String: optional URL query parameter string
1326  */
1327 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1328         global $wgLang;
1329         if( $query == '' ) {
1330                 $q = '';
1331         } else {
1332                 $q = $query.'&';
1333         }
1334         $q .= "limit={$limit}&offset={$offset}";
1335         $fmtLimit = $wgLang->formatNum( $limit );
1336         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1337         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1338         return $s;
1339 }
1340
1341 /**
1342  * @todo document
1343  * @todo FIXME: We may want to blacklist some broken browsers
1344  *
1345  * @param $force Bool
1346  * @return bool Whereas client accept gzip compression
1347  */
1348 function wfClientAcceptsGzip( $force = false ) {
1349         static $result = null;
1350         if ( $result === null || $force ) {
1351                 $result = false;
1352                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1353                         # @todo FIXME: We may want to blacklist some broken browsers
1354                         $m = array();
1355                         if( preg_match(
1356                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1357                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1358                                 $m )
1359                         )
1360                         {
1361                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1362                                         $result = false;
1363                                         return $result;
1364                                 }
1365                                 wfDebug( " accepts gzip\n" );
1366                                 $result = true;
1367                         }
1368                 }
1369         }
1370         return $result;
1371 }
1372
1373 /**
1374  * Obtain the offset and limit values from the request string;
1375  * used in special pages
1376  *
1377  * @param $deflimit Int default limit if none supplied
1378  * @param $optionname String Name of a user preference to check against
1379  * @return array
1380  *
1381  */
1382 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1383         global $wgRequest;
1384         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1385 }
1386
1387 /**
1388  * Escapes the given text so that it may be output using addWikiText()
1389  * without any linking, formatting, etc. making its way through. This
1390  * is achieved by substituting certain characters with HTML entities.
1391  * As required by the callers, <nowiki> is not used.
1392  *
1393  * @param $text String: text to be escaped
1394  * @return String
1395  */
1396 function wfEscapeWikiText( $text ) {
1397         $text = strtr( "\n$text", array(
1398                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1399                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1400                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1401                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1402                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1403                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1404         ) );
1405         return substr( $text, 1 );
1406 }
1407
1408 /**
1409  * Get the current unix timetstamp with microseconds.  Useful for profiling
1410  * @return Float
1411  */
1412 function wfTime() {
1413         return microtime( true );
1414 }
1415
1416 /**
1417  * Sets dest to source and returns the original value of dest
1418  * If source is NULL, it just returns the value, it doesn't set the variable
1419  * If force is true, it will set the value even if source is NULL
1420  *
1421  * @param $dest Mixed
1422  * @param $source Mixed
1423  * @param $force Bool
1424  * @return Mixed
1425  */
1426 function wfSetVar( &$dest, $source, $force = false ) {
1427         $temp = $dest;
1428         if ( !is_null( $source ) || $force ) {
1429                 $dest = $source;
1430         }
1431         return $temp;
1432 }
1433
1434 /**
1435  * As for wfSetVar except setting a bit
1436  *
1437  * @param $dest Int
1438  * @param $bit Int
1439  * @param $state Bool
1440  */
1441 function wfSetBit( &$dest, $bit, $state = true ) {
1442         $temp = (bool)( $dest & $bit );
1443         if ( !is_null( $state ) ) {
1444                 if ( $state ) {
1445                         $dest |= $bit;
1446                 } else {
1447                         $dest &= ~$bit;
1448                 }
1449         }
1450         return $temp;
1451 }
1452
1453 /**
1454  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1455  * "days=7&limit=100". Options in the first array override options in the second.
1456  * Options set to "" will not be output.
1457  *
1458  * @param $array1 Array( String|Array )
1459  * @param $array2 Array( String|Array )
1460  * @return String
1461  */
1462 function wfArrayToCGI( $array1, $array2 = null ) {
1463         if ( !is_null( $array2 ) ) {
1464                 $array1 = $array1 + $array2;
1465         }
1466
1467         $cgi = '';
1468         foreach ( $array1 as $key => $value ) {
1469                 if ( $value !== '' ) {
1470                         if ( $cgi != '' ) {
1471                                 $cgi .= '&';
1472                         }
1473                         if ( is_array( $value ) ) {
1474                                 $firstTime = true;
1475                                 foreach ( $value as $v ) {
1476                                         $cgi .= ( $firstTime ? '' : '&') .
1477                                                 urlencode( $key . '[]' ) . '=' .
1478                                                 urlencode( $v );
1479                                         $firstTime = false;
1480                                 }
1481                         } else {
1482                                 if ( is_object( $value ) ) {
1483                                         $value = $value->__toString();
1484                                 }
1485                                 $cgi .= urlencode( $key ) . '=' .
1486                                         urlencode( $value );
1487                         }
1488                 }
1489         }
1490         return $cgi;
1491 }
1492
1493 /**
1494  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1495  * its argument and returns the same string in array form.  This allows compa-
1496  * tibility with legacy functions that accept raw query strings instead of nice
1497  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1498  * valid query strings, or it will explode.
1499  *
1500  * @param $query String: query string
1501  * @return array Array version of input
1502  */
1503 function wfCgiToArray( $query ) {
1504         if( isset( $query[0] ) && $query[0] == '?' ) {
1505                 $query = substr( $query, 1 );
1506         }
1507         $bits = explode( '&', $query );
1508         $ret = array();
1509         foreach( $bits as $bit ) {
1510                 if( $bit === '' ) {
1511                         continue;
1512                 }
1513                 list( $key, $value ) = explode( '=', $bit );
1514                 $key = urldecode( $key );
1515                 $value = urldecode( $value );
1516                 $ret[$key] = $value;
1517         }
1518         return $ret;
1519 }
1520
1521 /**
1522  * Append a query string to an existing URL, which may or may not already
1523  * have query string parameters already. If so, they will be combined.
1524  *
1525  * @param $url String
1526  * @param $query Mixed: string or associative array
1527  * @return string
1528  */
1529 function wfAppendQuery( $url, $query ) {
1530         if ( is_array( $query ) ) {
1531                 $query = wfArrayToCGI( $query );
1532         }
1533         if( $query != '' ) {
1534                 if( false === strpos( $url, '?' ) ) {
1535                         $url .= '?';
1536                 } else {
1537                         $url .= '&';
1538                 }
1539                 $url .= $query;
1540         }
1541         return $url;
1542 }
1543
1544 /**
1545  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1546  * and $wgProto are correct.
1547  *
1548  * @todo this won't work with current-path-relative URLs
1549  * like "subdir/foo.html", etc.
1550  *
1551  * @param $url String: either fully-qualified or a local path + query
1552  * @return string Fully-qualified URL
1553  */
1554 function wfExpandUrl( $url ) {
1555         if( substr( $url, 0, 2 ) == '//' ) {
1556                 global $wgProto;
1557                 return $wgProto . ':' . $url;
1558         } elseif( substr( $url, 0, 1 ) == '/' ) {
1559                 global $wgServer;
1560                 return $wgServer . $url;
1561         } else {
1562                 return $url;
1563         }
1564 }
1565
1566 /**
1567  * Windows-compatible version of escapeshellarg()
1568  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1569  * function puts single quotes in regardless of OS.
1570  *
1571  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1572  * earlier distro releases of PHP)
1573  *
1574  * @param varargs
1575  * @return String
1576  */
1577 function wfEscapeShellArg( ) {
1578         wfInitShellLocale();
1579
1580         $args = func_get_args();
1581         $first = true;
1582         $retVal = '';
1583         foreach ( $args as $arg ) {
1584                 if ( !$first ) {
1585                         $retVal .= ' ';
1586                 } else {
1587                         $first = false;
1588                 }
1589
1590                 if ( wfIsWindows() ) {
1591                         // Escaping for an MSVC-style command line parser and CMD.EXE
1592                         // Refs:
1593                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1594                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1595                         //  * Bug #13518
1596                         //  * CR r63214
1597                         // Double the backslashes before any double quotes. Escape the double quotes.
1598                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1599                         $arg = '';
1600                         $iteration = 0;
1601                         foreach ( $tokens as $token ) {
1602                                 if ( $iteration % 2 == 1 ) {
1603                                         // Delimiter, a double quote preceded by zero or more slashes
1604                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1605                                 } elseif ( $iteration % 4 == 2 ) {
1606                                         // ^ in $token will be outside quotes, need to be escaped
1607                                         $arg .= str_replace( '^', '^^', $token );
1608                                 } else { // $iteration % 4 == 0
1609                                         // ^ in $token will appear inside double quotes, so leave as is
1610                                         $arg .= $token;
1611                                 }
1612                                 $iteration++;
1613                         }
1614                         // Double the backslashes before the end of the string, because
1615                         // we will soon add a quote
1616                         $m = array();
1617                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1618                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1619                         }
1620
1621                         // Add surrounding quotes
1622                         $retVal .= '"' . $arg . '"';
1623                 } else {
1624                         $retVal .= escapeshellarg( $arg );
1625                 }
1626         }
1627         return $retVal;
1628 }
1629
1630 /**
1631  * wfMerge attempts to merge differences between three texts.
1632  * Returns true for a clean merge and false for failure or a conflict.
1633  *
1634  * @param $old String
1635  * @param $mine String
1636  * @param $yours String
1637  * @param $result String
1638  * @return Bool
1639  */
1640 function wfMerge( $old, $mine, $yours, &$result ) {
1641         global $wgDiff3;
1642
1643         # This check may also protect against code injection in
1644         # case of broken installations.
1645         wfSuppressWarnings();
1646         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1647         wfRestoreWarnings();
1648
1649         if( !$haveDiff3 ) {
1650                 wfDebug( "diff3 not found\n" );
1651                 return false;
1652         }
1653
1654         # Make temporary files
1655         $td = wfTempDir();
1656         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1657         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1658         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1659
1660         fwrite( $oldtextFile, $old );
1661         fclose( $oldtextFile );
1662         fwrite( $mytextFile, $mine );
1663         fclose( $mytextFile );
1664         fwrite( $yourtextFile, $yours );
1665         fclose( $yourtextFile );
1666
1667         # Check for a conflict
1668         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1669                 wfEscapeShellArg( $mytextName ) . ' ' .
1670                 wfEscapeShellArg( $oldtextName ) . ' ' .
1671                 wfEscapeShellArg( $yourtextName );
1672         $handle = popen( $cmd, 'r' );
1673
1674         if( fgets( $handle, 1024 ) ) {
1675                 $conflict = true;
1676         } else {
1677                 $conflict = false;
1678         }
1679         pclose( $handle );
1680
1681         # Merge differences
1682         $cmd = $wgDiff3 . ' -a -e --merge ' .
1683                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1684         $handle = popen( $cmd, 'r' );
1685         $result = '';
1686         do {
1687                 $data = fread( $handle, 8192 );
1688                 if ( strlen( $data ) == 0 ) {
1689                         break;
1690                 }
1691                 $result .= $data;
1692         } while ( true );
1693         pclose( $handle );
1694         unlink( $mytextName );
1695         unlink( $oldtextName );
1696         unlink( $yourtextName );
1697
1698         if ( $result === '' && $old !== '' && !$conflict ) {
1699                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1700                 $conflict = true;
1701         }
1702         return !$conflict;
1703 }
1704
1705 /**
1706  * Returns unified plain-text diff of two texts.
1707  * Useful for machine processing of diffs.
1708  *
1709  * @param $before String: the text before the changes.
1710  * @param $after String: the text after the changes.
1711  * @param $params String: command-line options for the diff command.
1712  * @return String: unified diff of $before and $after
1713  */
1714 function wfDiff( $before, $after, $params = '-u' ) {
1715         if ( $before == $after ) {
1716                 return '';
1717         }
1718
1719         global $wgDiff;
1720         wfSuppressWarnings();
1721         $haveDiff = $wgDiff && file_exists( $wgDiff );
1722         wfRestoreWarnings();
1723
1724         # This check may also protect against code injection in
1725         # case of broken installations.
1726         if( !$haveDiff ) {
1727                 wfDebug( "diff executable not found\n" );
1728                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1729                 $format = new UnifiedDiffFormatter();
1730                 return $format->format( $diffs );
1731         }
1732
1733         # Make temporary files
1734         $td = wfTempDir();
1735         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1736         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1737
1738         fwrite( $oldtextFile, $before );
1739         fclose( $oldtextFile );
1740         fwrite( $newtextFile, $after );
1741         fclose( $newtextFile );
1742
1743         // Get the diff of the two files
1744         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1745
1746         $h = popen( $cmd, 'r' );
1747
1748         $diff = '';
1749
1750         do {
1751                 $data = fread( $h, 8192 );
1752                 if ( strlen( $data ) == 0 ) {
1753                         break;
1754                 }
1755                 $diff .= $data;
1756         } while ( true );
1757
1758         // Clean up
1759         pclose( $h );
1760         unlink( $oldtextName );
1761         unlink( $newtextName );
1762
1763         // Kill the --- and +++ lines. They're not useful.
1764         $diff_lines = explode( "\n", $diff );
1765         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1766                 unset( $diff_lines[0] );
1767         }
1768         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1769                 unset( $diff_lines[1] );
1770         }
1771
1772         $diff = implode( "\n", $diff_lines );
1773
1774         return $diff;
1775 }
1776
1777 /**
1778  * A wrapper around the PHP function var_export().
1779  * Either print it or add it to the regular output ($wgOut).
1780  *
1781  * @param $var A PHP variable to dump.
1782  */
1783 function wfVarDump( $var ) {
1784         global $wgOut;
1785         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1786         if ( headers_sent() || !@is_object( $wgOut ) ) {
1787                 print $s;
1788         } else {
1789                 $wgOut->addHTML( $s );
1790         }
1791 }
1792
1793 /**
1794  * Provide a simple HTTP error.
1795  *
1796  * @param $code Int|String
1797  * @param $label String
1798  * @param $desc String
1799  */
1800 function wfHttpError( $code, $label, $desc ) {
1801         global $wgOut;
1802         $wgOut->disable();
1803         header( "HTTP/1.0 $code $label" );
1804         header( "Status: $code $label" );
1805         $wgOut->sendCacheControl();
1806
1807         header( 'Content-type: text/html; charset=utf-8' );
1808         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1809                 '<html><head><title>' .
1810                 htmlspecialchars( $label ) .
1811                 '</title></head><body><h1>' .
1812                 htmlspecialchars( $label ) .
1813                 '</h1><p>' .
1814                 nl2br( htmlspecialchars( $desc ) ) .
1815                 "</p></body></html>\n";
1816 }
1817
1818 /**
1819  * Clear away any user-level output buffers, discarding contents.
1820  *
1821  * Suitable for 'starting afresh', for instance when streaming
1822  * relatively large amounts of data without buffering, or wanting to
1823  * output image files without ob_gzhandler's compression.
1824  *
1825  * The optional $resetGzipEncoding parameter controls suppression of
1826  * the Content-Encoding header sent by ob_gzhandler; by default it
1827  * is left. See comments for wfClearOutputBuffers() for why it would
1828  * be used.
1829  *
1830  * Note that some PHP configuration options may add output buffer
1831  * layers which cannot be removed; these are left in place.
1832  *
1833  * @param $resetGzipEncoding Bool
1834  */
1835 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1836         if( $resetGzipEncoding ) {
1837                 // Suppress Content-Encoding and Content-Length
1838                 // headers from 1.10+s wfOutputHandler
1839                 global $wgDisableOutputCompression;
1840                 $wgDisableOutputCompression = true;
1841         }
1842         while( $status = ob_get_status() ) {
1843                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1844                         // Probably from zlib.output_compression or other
1845                         // PHP-internal setting which can't be removed.
1846                         //
1847                         // Give up, and hope the result doesn't break
1848                         // output behavior.
1849                         break;
1850                 }
1851                 if( !ob_end_clean() ) {
1852                         // Could not remove output buffer handler; abort now
1853                         // to avoid getting in some kind of infinite loop.
1854                         break;
1855                 }
1856                 if( $resetGzipEncoding ) {
1857                         if( $status['name'] == 'ob_gzhandler' ) {
1858                                 // Reset the 'Content-Encoding' field set by this handler
1859                                 // so we can start fresh.
1860                                 if ( function_exists( 'header_remove' ) ) {
1861                                         // Available since PHP 5.3.0
1862                                         header_remove( 'Content-Encoding' );
1863                                 } else {
1864                                         // We need to provide a valid content-coding. See bug 28069
1865                                         header( 'Content-Encoding: identity' );
1866                                 }
1867                                 break;
1868                         }
1869                 }
1870         }
1871 }
1872
1873 /**
1874  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1875  *
1876  * Clear away output buffers, but keep the Content-Encoding header
1877  * produced by ob_gzhandler, if any.
1878  *
1879  * This should be used for HTTP 304 responses, where you need to
1880  * preserve the Content-Encoding header of the real result, but
1881  * also need to suppress the output of ob_gzhandler to keep to spec
1882  * and avoid breaking Firefox in rare cases where the headers and
1883  * body are broken over two packets.
1884  */
1885 function wfClearOutputBuffers() {
1886         wfResetOutputBuffers( false );
1887 }
1888
1889 /**
1890  * Converts an Accept-* header into an array mapping string values to quality
1891  * factors
1892  *
1893  * @param $accept String
1894  * @param $def String default
1895  * @return Array
1896  */
1897 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1898         # No arg means accept anything (per HTTP spec)
1899         if( !$accept ) {
1900                 return array( $def => 1.0 );
1901         }
1902
1903         $prefs = array();
1904
1905         $parts = explode( ',', $accept );
1906
1907         foreach( $parts as $part ) {
1908                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1909                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1910                 $match = array();
1911                 if( !isset( $qpart ) ) {
1912                         $prefs[$value] = 1.0;
1913                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1914                         $prefs[$value] = floatval( $match[1] );
1915                 }
1916         }
1917
1918         return $prefs;
1919 }
1920
1921 /**
1922  * Checks if a given MIME type matches any of the keys in the given
1923  * array. Basic wildcards are accepted in the array keys.
1924  *
1925  * Returns the matching MIME type (or wildcard) if a match, otherwise
1926  * NULL if no match.
1927  *
1928  * @param $type String
1929  * @param $avail Array
1930  * @return string
1931  * @private
1932  */
1933 function mimeTypeMatch( $type, $avail ) {
1934         if( array_key_exists( $type, $avail ) ) {
1935                 return $type;
1936         } else {
1937                 $parts = explode( '/', $type );
1938                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1939                         return $parts[0] . '/*';
1940                 } elseif( array_key_exists( '*/*', $avail ) ) {
1941                         return '*/*';
1942                 } else {
1943                         return null;
1944                 }
1945         }
1946 }
1947
1948 /**
1949  * Returns the 'best' match between a client's requested internet media types
1950  * and the server's list of available types. Each list should be an associative
1951  * array of type to preference (preference is a float between 0.0 and 1.0).
1952  * Wildcards in the types are acceptable.
1953  *
1954  * @param $cprefs Array: client's acceptable type list
1955  * @param $sprefs Array: server's offered types
1956  * @return string
1957  *
1958  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1959  * XXX: generalize to negotiate other stuff
1960  */
1961 function wfNegotiateType( $cprefs, $sprefs ) {
1962         $combine = array();
1963
1964         foreach( array_keys($sprefs) as $type ) {
1965                 $parts = explode( '/', $type );
1966                 if( $parts[1] != '*' ) {
1967                         $ckey = mimeTypeMatch( $type, $cprefs );
1968                         if( $ckey ) {
1969                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1970                         }
1971                 }
1972         }
1973
1974         foreach( array_keys( $cprefs ) as $type ) {
1975                 $parts = explode( '/', $type );
1976                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1977                         $skey = mimeTypeMatch( $type, $sprefs );
1978                         if( $skey ) {
1979                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1980                         }
1981                 }
1982         }
1983
1984         $bestq = 0;
1985         $besttype = null;
1986
1987         foreach( array_keys( $combine ) as $type ) {
1988                 if( $combine[$type] > $bestq ) {
1989                         $besttype = $type;
1990                         $bestq = $combine[$type];
1991                 }
1992         }
1993
1994         return $besttype;
1995 }
1996
1997 /**
1998  * Reference-counted warning suppression
1999  *
2000  * @param $end Bool
2001  */
2002 function wfSuppressWarnings( $end = false ) {
2003         static $suppressCount = 0;
2004         static $originalLevel = false;
2005
2006         if ( $end ) {
2007                 if ( $suppressCount ) {
2008                         --$suppressCount;
2009                         if ( !$suppressCount ) {
2010                                 error_reporting( $originalLevel );
2011                         }
2012                 }
2013         } else {
2014                 if ( !$suppressCount ) {
2015                         // E_DEPRECATED is undefined in PHP 5.2
2016                         if( !defined( 'E_DEPRECATED' ) ){
2017                                 define( 'E_DEPRECATED', 8192 );
2018                         }
2019                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2020                 }
2021                 ++$suppressCount;
2022         }
2023 }
2024
2025 /**
2026  * Restore error level to previous value
2027  */
2028 function wfRestoreWarnings() {
2029         wfSuppressWarnings( true );
2030 }
2031
2032 # Autodetect, convert and provide timestamps of various types
2033
2034 /**
2035  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2036  */
2037 define( 'TS_UNIX', 0 );
2038
2039 /**
2040  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2041  */
2042 define( 'TS_MW', 1 );
2043
2044 /**
2045  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2046  */
2047 define( 'TS_DB', 2 );
2048
2049 /**
2050  * RFC 2822 format, for E-mail and HTTP headers
2051  */
2052 define( 'TS_RFC2822', 3 );
2053
2054 /**
2055  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2056  *
2057  * This is used by Special:Export
2058  */
2059 define( 'TS_ISO_8601', 4 );
2060
2061 /**
2062  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2063  *
2064  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2065  *       DateTime tag and page 36 for the DateTimeOriginal and
2066  *       DateTimeDigitized tags.
2067  */
2068 define( 'TS_EXIF', 5 );
2069
2070 /**
2071  * Oracle format time.
2072  */
2073 define( 'TS_ORACLE', 6 );
2074
2075 /**
2076  * Postgres format time.
2077  */
2078 define( 'TS_POSTGRES', 7 );
2079
2080 /**
2081  * DB2 format time
2082  */
2083 define( 'TS_DB2', 8 );
2084
2085 /**
2086  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2087  */
2088 define( 'TS_ISO_8601_BASIC', 9 );
2089
2090 /**
2091  * Get a timestamp string in one of various formats
2092  *
2093  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2094  *                    function will autodetect which format is supplied and act
2095  *                    accordingly.
2096  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2097  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2098  */
2099 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2100         $uts = 0;
2101         $da = array();
2102         $strtime = '';
2103
2104         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2105                 $uts = time();
2106                 $strtime = "@$uts";
2107         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2108                 # TS_DB
2109         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2110                 # TS_EXIF
2111         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2112                 # TS_MW
2113         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2114                 # TS_UNIX
2115                 $uts = $ts;
2116                 $strtime = "@$ts"; // Undocumented?
2117         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2118                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2119                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2120                                 str_replace( '+00:00', 'UTC', $ts ) );
2121         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2122                 # TS_ISO_8601
2123         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2124                 #TS_ISO_8601_BASIC
2125         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2126                 # TS_POSTGRES
2127         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2128                 # TS_POSTGRES
2129         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2130                 # TS_DB2
2131         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2132                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2133                                                         '[ \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
2134                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2135                 # The regex is a superset of rfc2822 for readability
2136                 $strtime = strtok( $ts, ';' );
2137         } 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 ) ) {
2138                 # TS_RFC850
2139                 $strtime = $ts;
2140         } 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 ) ) {
2141                 # asctime
2142                 $strtime = $ts;
2143         } else {
2144                 # Bogus value...
2145                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2146
2147                 return false;
2148         }
2149
2150
2151
2152         static $formats = array(
2153                 TS_UNIX => 'U',
2154                 TS_MW => 'YmdHis',
2155                 TS_DB => 'Y-m-d H:i:s',
2156                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2157                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2158                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2159                 TS_RFC2822 => 'D, d M Y H:i:s',
2160                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2161                 TS_POSTGRES => 'Y-m-d H:i:s',
2162                 TS_DB2 => 'Y-m-d H:i:s',
2163         );
2164
2165         if ( !isset( $formats[$outputtype] ) ) {
2166                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2167         }
2168
2169         if ( function_exists( "date_create" ) ) {
2170                 if ( count( $da ) ) {
2171                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2172                                 (int)$da[1], (int)$da[2], (int)$da[3],
2173                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2174
2175                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2176                 } elseif ( $strtime ) {
2177                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2178                 } else {
2179                         return false;
2180                 }
2181
2182                 if ( !$d ) {
2183                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2184                         return false;
2185                 }
2186
2187                 $output = $d->format( $formats[$outputtype] );
2188         } else {
2189                 if ( count( $da ) ) {
2190                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2191                         // We may want to handle that explicitly at some point
2192                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2193                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2194                 } elseif ( $strtime ) {
2195                         $uts = strtotime( $strtime );
2196                 }
2197
2198                 if ( $uts === false ) {
2199                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2200                         return false;
2201                 }
2202
2203                 if ( TS_UNIX == $outputtype ) {
2204                         return $uts;
2205                 }
2206                 $output = gmdate( $formats[$outputtype], $uts );
2207         }
2208
2209         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2210                 $output .= ' GMT';
2211         }
2212
2213         return $output;
2214 }
2215
2216 /**
2217  * Return a formatted timestamp, or null if input is null.
2218  * For dealing with nullable timestamp columns in the database.
2219  *
2220  * @param $outputtype Integer
2221  * @param $ts String
2222  * @return String
2223  */
2224 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2225         if( is_null( $ts ) ) {
2226                 return null;
2227         } else {
2228                 return wfTimestamp( $outputtype, $ts );
2229         }
2230 }
2231
2232 /**
2233  * Convenience function; returns MediaWiki timestamp for the present time.
2234  *
2235  * @return string
2236  */
2237 function wfTimestampNow() {
2238         # return NOW
2239         return wfTimestamp( TS_MW, time() );
2240 }
2241
2242 /**
2243  * Check if the operating system is Windows
2244  *
2245  * @return Bool: true if it's Windows, False otherwise.
2246  */
2247 function wfIsWindows() {
2248         static $isWindows = null;
2249         if ( $isWindows === null ) {
2250                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2251         }
2252         return $isWindows;
2253 }
2254
2255 /**
2256  * Check if we are running under HipHop
2257  *
2258  * @return Bool
2259  */
2260 function wfIsHipHop() {
2261         return function_exists( 'hphp_thread_set_warmup_enabled' );
2262 }
2263
2264 /**
2265  * Swap two variables
2266  *
2267  * @param $x Mixed
2268  * @param $y Mixed
2269  */
2270 function swap( &$x, &$y ) {
2271         $z = $x;
2272         $x = $y;
2273         $y = $z;
2274 }
2275
2276 /**
2277  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2278  * TEMP environment variables are then checked in sequence, and if none are set
2279  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2280  * or C:\Windows\Temp for Windows and hope for the best.
2281  * It is common to call it with tempnam().
2282  *
2283  * NOTE: When possible, use instead the tmpfile() function to create
2284  * temporary files to avoid race conditions on file creation, etc.
2285  *
2286  * @return String
2287  */
2288 function wfTempDir() {
2289         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2290                 $tmp = getenv( $var );
2291                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2292                         return $tmp;
2293                 }
2294         }
2295         if( function_exists( 'sys_get_temp_dir' ) ) {
2296                 return sys_get_temp_dir();
2297         }
2298         # Usual defaults
2299         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2300 }
2301
2302 /**
2303  * Make directory, and make all parent directories if they don't exist
2304  *
2305  * @param $dir String: full path to directory to create
2306  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2307  * @param $caller String: optional caller param for debugging.
2308  * @return bool
2309  */
2310 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2311         global $wgDirectoryMode;
2312
2313         if ( !is_null( $caller ) ) {
2314                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2315         }
2316
2317         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2318                 return true;
2319         }
2320
2321         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2322
2323         if ( is_null( $mode ) ) {
2324                 $mode = $wgDirectoryMode;
2325         }
2326
2327         // Turn off the normal warning, we're doing our own below
2328         wfSuppressWarnings();
2329         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2330         wfRestoreWarnings();
2331
2332         if( !$ok ) {
2333                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2334                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2335         }
2336         return $ok;
2337 }
2338
2339 /**
2340  * Increment a statistics counter
2341  *
2342  * @param $key String
2343  * @param $count Int
2344  */
2345 function wfIncrStats( $key, $count = 1 ) {
2346         global $wgStatsMethod;
2347
2348         $count = intval( $count );
2349
2350         if( $wgStatsMethod == 'udp' ) {
2351                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2352                 static $socket;
2353
2354                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2355
2356                 if ( !$socket ) {
2357                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2358                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2359                         socket_sendto(
2360                                 $socket,
2361                                 $statline,
2362                                 strlen( $statline ),
2363                                 0,
2364                                 $wgUDPProfilerHost,
2365                                 $wgUDPProfilerPort
2366                         );
2367                 }
2368                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2369                 wfSuppressWarnings();
2370                 socket_sendto(
2371                         $socket,
2372                         $statline,
2373                         strlen( $statline ),
2374                         0,
2375                         $wgUDPProfilerHost,
2376                         $wgUDPProfilerPort
2377                 );
2378                 wfRestoreWarnings();
2379         } elseif( $wgStatsMethod == 'cache' ) {
2380                 global $wgMemc;
2381                 $key = wfMemcKey( 'stats', $key );
2382                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2383                         $wgMemc->add( $key, $count );
2384                 }
2385         } else {
2386                 // Disabled
2387         }
2388 }
2389
2390 /**
2391  * @param $nr Mixed: the number to format
2392  * @param $acc Integer: the number of digits after the decimal point, default 2
2393  * @param $round Boolean: whether or not to round the value, default true
2394  * @return float
2395  */
2396 function wfPercent( $nr, $acc = 2, $round = true ) {
2397         $ret = sprintf( "%.${acc}f", $nr );
2398         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2399 }
2400
2401 /**
2402  * Find out whether or not a mixed variable exists in a string
2403  *
2404  * @param $needle String
2405  * @param $str String
2406  * @param $insensitive Boolean
2407  * @return Boolean
2408  */
2409 function in_string( $needle, $str, $insensitive = false ) {
2410         $func = 'strpos';
2411         if( $insensitive ) $func = 'stripos';
2412
2413         return $func( $str, $needle ) !== false;
2414 }
2415
2416 function wfSpecialList( $page, $details ) {
2417         global $wgContLang;
2418         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2419         return $page . $details;
2420 }
2421
2422 /**
2423  * Returns a regular expression of url protocols
2424  *
2425  * @return String
2426  */
2427 function wfUrlProtocols() {
2428         global $wgUrlProtocols;
2429
2430         static $retval = null;
2431         if ( !is_null( $retval ) ) {
2432                 return $retval;
2433         }
2434
2435         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2436         // with LocalSettings files from 1.5
2437         if ( is_array( $wgUrlProtocols ) ) {
2438                 $protocols = array();
2439                 foreach ( $wgUrlProtocols as $protocol ) {
2440                         $protocols[] = preg_quote( $protocol, '/' );
2441                 }
2442
2443                 $retval = implode( '|', $protocols );
2444         } else {
2445                 $retval = $wgUrlProtocols;
2446         }
2447         return $retval;
2448 }
2449
2450 /**
2451  * Safety wrapper around ini_get() for boolean settings.
2452  * The values returned from ini_get() are pre-normalized for settings
2453  * set via php.ini or php_flag/php_admin_flag... but *not*
2454  * for those set via php_value/php_admin_value.
2455  *
2456  * It's fairly common for people to use php_value instead of php_flag,
2457  * which can leave you with an 'off' setting giving a false positive
2458  * for code that just takes the ini_get() return value as a boolean.
2459  *
2460  * To make things extra interesting, setting via php_value accepts
2461  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2462  * Unrecognized values go false... again opposite PHP's own coercion
2463  * from string to bool.
2464  *
2465  * Luckily, 'properly' set settings will always come back as '0' or '1',
2466  * so we only have to worry about them and the 'improper' settings.
2467  *
2468  * I frickin' hate PHP... :P
2469  *
2470  * @param $setting String
2471  * @return Bool
2472  */
2473 function wfIniGetBool( $setting ) {
2474         $val = ini_get( $setting );
2475         // 'on' and 'true' can't have whitespace around them, but '1' can.
2476         return strtolower( $val ) == 'on'
2477                 || strtolower( $val ) == 'true'
2478                 || strtolower( $val ) == 'yes'
2479                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2480 }
2481
2482 /**
2483  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2484  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2485  *
2486  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2487  *                          should be omitted
2488  * @param $fileName String Name of the library, if not $extension.suffix
2489  * @return Bool - Whether or not the extension is loaded
2490  */
2491 function wfDl( $extension, $fileName = null ) {
2492         if( extension_loaded( $extension ) ) {
2493                 return true;
2494         }
2495
2496         $canDl = false;
2497         $sapi = php_sapi_name();
2498         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2499                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2500         {
2501                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2502                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2503         }
2504
2505         if( $canDl ) {
2506                 $fileName = $fileName ? $fileName : $extension;
2507                 if( wfIsWindows() ) {
2508                         $fileName = 'php_' . $fileName;
2509                 }
2510                 wfSuppressWarnings();
2511                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2512                 wfRestoreWarnings();
2513         }
2514         return extension_loaded( $extension );
2515 }
2516
2517 /**
2518  * Execute a shell command, with time and memory limits mirrored from the PHP
2519  * configuration if supported.
2520  * @param $cmd String Command line, properly escaped for shell.
2521  * @param &$retval optional, will receive the program's exit code.
2522  *                 (non-zero is usually failure)
2523  * @param $environ Array optional environment variables which should be
2524  *                 added to the executed command environment.
2525  * @return collected stdout as a string (trailing newlines stripped)
2526  */
2527 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2528         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2529
2530         static $disabled;
2531         if ( is_null( $disabled ) ) {
2532                 $disabled = false;
2533                 if( wfIniGetBool( 'safe_mode' ) ) {
2534                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2535                         $disabled = 'safemode';
2536                 } else {
2537                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2538                         $functions = array_map( 'trim', $functions );
2539                         $functions = array_map( 'strtolower', $functions );
2540                         if ( in_array( 'passthru', $functions ) ) {
2541                                 wfDebug( "passthru is in disabled_functions\n" );
2542                                 $disabled = 'passthru';
2543                         }
2544                 }
2545         }
2546         if ( $disabled ) {
2547                 $retval = 1;
2548                 return $disabled == 'safemode' ?
2549                         'Unable to run external programs in safe mode.' :
2550                         'Unable to run external programs, passthru() is disabled.';
2551         }
2552
2553         wfInitShellLocale();
2554
2555         $envcmd = '';
2556         foreach( $environ as $k => $v ) {
2557                 if ( wfIsWindows() ) {
2558                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2559                          * appear in the environment variable, so we must use carat escaping as documented in
2560                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2561                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2562                          * are listed there but doesn't appear to need it.
2563                          */
2564                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2565                 } else {
2566                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2567                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2568                          */
2569                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2570                 }
2571         }
2572         $cmd = $envcmd . $cmd;
2573
2574         if ( wfIsWindows() ) {
2575                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2576                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2577                 {
2578                         # Hack to work around PHP's flawed invocation of cmd.exe
2579                         # http://news.php.net/php.internals/21796
2580                         # Windows 9x doesn't accept any kind of quotes
2581                         $cmd = '"' . $cmd . '"';
2582                 }
2583         } elseif ( php_uname( 's' ) == 'Linux' ) {
2584                 $time = intval( $wgMaxShellTime );
2585                 $mem = intval( $wgMaxShellMemory );
2586                 $filesize = intval( $wgMaxShellFileSize );
2587
2588                 if ( $time > 0 && $mem > 0 ) {
2589                         $script = "$IP/bin/ulimit4.sh";
2590                         if ( is_executable( $script ) ) {
2591                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2592                         }
2593                 }
2594         }
2595         wfDebug( "wfShellExec: $cmd\n" );
2596
2597         $retval = 1; // error by default?
2598         ob_start();
2599         passthru( $cmd, $retval );
2600         $output = ob_get_contents();
2601         ob_end_clean();
2602
2603         if ( $retval == 127 ) {
2604                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2605         }
2606         return $output;
2607 }
2608
2609 /**
2610  * Workaround for http://bugs.php.net/bug.php?id=45132
2611  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2612  */
2613 function wfInitShellLocale() {
2614         static $done = false;
2615         if ( $done ) {
2616                 return;
2617         }
2618         $done = true;
2619         global $wgShellLocale;
2620         if ( !wfIniGetBool( 'safe_mode' ) ) {
2621                 putenv( "LC_CTYPE=$wgShellLocale" );
2622                 setlocale( LC_CTYPE, $wgShellLocale );
2623         }
2624 }
2625
2626 /**
2627  * This function works like "use VERSION" in Perl, the program will die with a
2628  * backtrace if the current version of PHP is less than the version provided
2629  *
2630  * This is useful for extensions which due to their nature are not kept in sync
2631  * with releases, and might depend on other versions of PHP than the main code
2632  *
2633  * Note: PHP might die due to parsing errors in some cases before it ever
2634  *       manages to call this function, such is life
2635  *
2636  * @see perldoc -f use
2637  *
2638  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2639  *                 a float
2640  */
2641 function wfUsePHP( $req_ver ) {
2642         $php_ver = PHP_VERSION;
2643
2644         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2645                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2646         }
2647 }
2648
2649 /**
2650  * This function works like "use VERSION" in Perl except it checks the version
2651  * of MediaWiki, the program will die with a backtrace if the current version
2652  * of MediaWiki is less than the version provided.
2653  *
2654  * This is useful for extensions which due to their nature are not kept in sync
2655  * with releases
2656  *
2657  * @see perldoc -f use
2658  *
2659  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2660  *                 a float
2661  */
2662 function wfUseMW( $req_ver ) {
2663         global $wgVersion;
2664
2665         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2666                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2667         }
2668 }
2669
2670 /**
2671  * Return the final portion of a pathname.
2672  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2673  * http://bugs.php.net/bug.php?id=33898
2674  *
2675  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2676  * We'll consider it so always, as we don't want \s in our Unix paths either.
2677  *
2678  * @param $path String
2679  * @param $suffix String: to remove if present
2680  * @return String
2681  */
2682 function wfBaseName( $path, $suffix = '' ) {
2683         $encSuffix = ( $suffix == '' )
2684                 ? ''
2685                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2686         $matches = array();
2687         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2688                 return $matches[1];
2689         } else {
2690                 return '';
2691         }
2692 }
2693
2694 /**
2695  * Generate a relative path name to the given file.
2696  * May explode on non-matching case-insensitive paths,
2697  * funky symlinks, etc.
2698  *
2699  * @param $path String: absolute destination path including target filename
2700  * @param $from String: Absolute source path, directory only
2701  * @return String
2702  */
2703 function wfRelativePath( $path, $from ) {
2704         // Normalize mixed input on Windows...
2705         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2706         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2707
2708         // Trim trailing slashes -- fix for drive root
2709         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2710         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2711
2712         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2713         $against = explode( DIRECTORY_SEPARATOR, $from );
2714
2715         if( $pieces[0] !== $against[0] ) {
2716                 // Non-matching Windows drive letters?
2717                 // Return a full path.
2718                 return $path;
2719         }
2720
2721         // Trim off common prefix
2722         while( count( $pieces ) && count( $against )
2723                 && $pieces[0] == $against[0] ) {
2724                 array_shift( $pieces );
2725                 array_shift( $against );
2726         }
2727
2728         // relative dots to bump us to the parent
2729         while( count( $against ) ) {
2730                 array_unshift( $pieces, '..' );
2731                 array_shift( $against );
2732         }
2733
2734         array_push( $pieces, wfBaseName( $path ) );
2735
2736         return implode( DIRECTORY_SEPARATOR, $pieces );
2737 }
2738
2739 /**
2740  * parse_url() work-alike, but non-broken.  Differences:
2741  *
2742  * 1) Does not raise warnings on bad URLs (just returns false)
2743  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2744  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2745  *
2746  * @param $url String: a URL to parse
2747  * @return Array: bits of the URL in an associative array, per PHP docs
2748  */
2749 function wfParseUrl( $url ) {
2750         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2751         wfSuppressWarnings();
2752         $bits = parse_url( $url );
2753         wfRestoreWarnings();
2754         if ( !$bits ) {
2755                 return false;
2756         }
2757
2758         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2759         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2760                 $bits['delimiter'] = '://';
2761         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2762                 $bits['delimiter'] = ':';
2763                 // parse_url detects for news: and mailto: the host part of an url as path
2764                 // We have to correct this wrong detection
2765                 if ( isset( $bits['path'] ) ) {
2766                         $bits['host'] = $bits['path'];
2767                         $bits['path'] = '';
2768                 }
2769         } else {
2770                 return false;
2771         }
2772
2773         return $bits;
2774 }
2775
2776 /**
2777  * Make a URL index, appropriate for the el_index field of externallinks.
2778  *
2779  * @param $url String
2780  * @return String
2781  */
2782 function wfMakeUrlIndex( $url ) {
2783         $bits = wfParseUrl( $url );
2784
2785         // Reverse the labels in the hostname, convert to lower case
2786         // For emails reverse domainpart only
2787         if ( $bits['scheme'] == 'mailto' ) {
2788                 $mailparts = explode( '@', $bits['host'], 2 );
2789                 if ( count( $mailparts ) === 2 ) {
2790                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2791                 } else {
2792                         // No domain specified, don't mangle it
2793                         $domainpart = '';
2794                 }
2795                 $reversedHost = $domainpart . '@' . $mailparts[0];
2796         } else if ( isset( $bits['host'] ) ) {
2797                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2798         } else {
2799                 // In file: URIs for instance it's common to have an empty host,
2800                 // which turns up as not getting a 'host' member from parse_url.
2801                 $reversedHost = '.';
2802         }
2803         // Add an extra dot to the end
2804         // Why? Is it in wrong place in mailto links?
2805         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2806                 $reversedHost .= '.';
2807         }
2808         // Reconstruct the pseudo-URL
2809         $prot = $bits['scheme'];
2810         $index = $prot . $bits['delimiter'] . $reversedHost;
2811         // Leave out user and password. Add the port, path, query and fragment
2812         if ( isset( $bits['port'] ) ) {
2813                 $index .= ':' . $bits['port'];
2814         }
2815         if ( isset( $bits['path'] ) ) {
2816                 // parse_url() removes the initial '/' from the path
2817                 // for file: URLs with Windows-style paths, such as
2818                 // file:///c:/windows/stuff. We need to add it back
2819                 // to keep our division between host and path properly.
2820                 if ( strlen( $bits['path'] ) > 0 && substr( $bits['path'], 0, 1 ) !== '/' ) {
2821                         $index .= '/';
2822                 }
2823                 $index .= $bits['path'];
2824         } else {
2825                 $index .= '/';
2826         }
2827         if ( isset( $bits['query'] ) ) {
2828                 $index .= '?' . $bits['query'];
2829         }
2830         if ( isset( $bits['fragment'] ) ) {
2831                 $index .= '#' . $bits['fragment'];
2832         }
2833         return $index;
2834 }
2835
2836 /**
2837  * Do any deferred updates and clear the list
2838  *
2839  * @param $commit String: set to 'commit' to commit after every update to
2840  *                prevent lock contention
2841  */
2842 function wfDoUpdates( $commit = '' ) {
2843         global $wgDeferredUpdateList;
2844
2845         wfProfileIn( __METHOD__ );
2846
2847         // No need to get master connections in case of empty updates array
2848         if ( !count( $wgDeferredUpdateList ) ) {
2849                 wfProfileOut( __METHOD__ );
2850                 return;
2851         }
2852
2853         $doCommit = $commit == 'commit';
2854         if ( $doCommit ) {
2855                 $dbw = wfGetDB( DB_MASTER );
2856         }
2857
2858         foreach ( $wgDeferredUpdateList as $update ) {
2859                 $update->doUpdate();
2860
2861                 if ( $doCommit && $dbw->trxLevel() ) {
2862                         $dbw->commit();
2863                 }
2864         }
2865
2866         $wgDeferredUpdateList = array();
2867         wfProfileOut( __METHOD__ );
2868 }
2869
2870 /**
2871  * Convert an arbitrarily-long digit string from one numeric base
2872  * to another, optionally zero-padding to a minimum column width.
2873  *
2874  * Supports base 2 through 36; digit values 10-36 are represented
2875  * as lowercase letters a-z. Input is case-insensitive.
2876  *
2877  * @param $input String: of digits
2878  * @param $sourceBase Integer: 2-36
2879  * @param $destBase Integer: 2-36
2880  * @param $pad Integer: 1 or greater
2881  * @param $lowercase Boolean
2882  * @return String or false on invalid input
2883  */
2884 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2885         $input = strval( $input );
2886         if( $sourceBase < 2 ||
2887                 $sourceBase > 36 ||
2888                 $destBase < 2 ||
2889                 $destBase > 36 ||
2890                 $pad < 1 ||
2891                 $sourceBase != intval( $sourceBase ) ||
2892                 $destBase != intval( $destBase ) ||
2893                 $pad != intval( $pad ) ||
2894                 !is_string( $input ) ||
2895                 $input == '' ) {
2896                 return false;
2897         }
2898         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2899         $inDigits = array();
2900         $outChars = '';
2901
2902         // Decode and validate input string
2903         $input = strtolower( $input );
2904         for( $i = 0; $i < strlen( $input ); $i++ ) {
2905                 $n = strpos( $digitChars, $input[$i] );
2906                 if( $n === false || $n > $sourceBase ) {
2907                         return false;
2908                 }
2909                 $inDigits[] = $n;
2910         }
2911
2912         // Iterate over the input, modulo-ing out an output digit
2913         // at a time until input is gone.
2914         while( count( $inDigits ) ) {
2915                 $work = 0;
2916                 $workDigits = array();
2917
2918                 // Long division...
2919                 foreach( $inDigits as $digit ) {
2920                         $work *= $sourceBase;
2921                         $work += $digit;
2922
2923                         if( $work < $destBase ) {
2924                                 // Gonna need to pull another digit.
2925                                 if( count( $workDigits ) ) {
2926                                         // Avoid zero-padding; this lets us find
2927                                         // the end of the input very easily when
2928                                         // length drops to zero.
2929                                         $workDigits[] = 0;
2930                                 }
2931                         } else {
2932                                 // Finally! Actual division!
2933                                 $workDigits[] = intval( $work / $destBase );
2934
2935                                 // Isn't it annoying that most programming languages
2936                                 // don't have a single divide-and-remainder operator,
2937                                 // even though the CPU implements it that way?
2938                                 $work = $work % $destBase;
2939                         }
2940                 }
2941
2942                 // All that division leaves us with a remainder,
2943                 // which is conveniently our next output digit.
2944                 $outChars .= $digitChars[$work];
2945
2946                 // And we continue!
2947                 $inDigits = $workDigits;
2948         }
2949
2950         while( strlen( $outChars ) < $pad ) {
2951                 $outChars .= '0';
2952         }
2953
2954         return strrev( $outChars );
2955 }
2956
2957 /**
2958  * Create an object with a given name and an array of construct parameters
2959  *
2960  * @param $name String
2961  * @param $p Array: parameters
2962  * @deprecated since 1.18, warnings in 1.19, removal in 1.20
2963  */
2964 function wfCreateObject( $name, $p ) {
2965         wfDeprecated( __FUNCTION__ );
2966         return MWFunction::newObj( $name, $p );
2967 }
2968
2969 function wfHttpOnlySafe() {
2970         global $wgHttpOnlyBlacklist;
2971
2972         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2973                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2974                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2975                                 return false;
2976                         }
2977                 }
2978         }
2979
2980         return true;
2981 }
2982
2983 /**
2984  * Initialise php session
2985  *
2986  * @param $sessionId Bool
2987  */
2988 function wfSetupSession( $sessionId = false ) {
2989         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
2990                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
2991         if( $wgSessionsInMemcached ) {
2992                 if ( !defined( 'MW_COMPILED' ) ) {
2993                         global $IP;
2994                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
2995                 }
2996                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
2997                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
2998
2999                 // It's necessary to register a shutdown function to call session_write_close(),
3000                 // because by the time the request shutdown function for the session module is
3001                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3002                 // this way are called before object destruction.
3003                 register_shutdown_function( 'memsess_write_close' );
3004         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3005                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3006                 # hasn't already been set to the desired value (that causes errors)
3007                 ini_set( 'session.save_handler', $wgSessionHandler );
3008         }
3009         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3010         wfDebugLog( 'cookie',
3011                 'session_set_cookie_params: "' . implode( '", "',
3012                         array(
3013                                 0,
3014                                 $wgCookiePath,
3015                                 $wgCookieDomain,
3016                                 $wgCookieSecure,
3017                                 $httpOnlySafe ) ) . '"' );
3018         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3019         session_cache_limiter( 'private, must-revalidate' );
3020         if ( $sessionId ) {
3021                 session_id( $sessionId );
3022         }
3023         wfSuppressWarnings();
3024         session_start();
3025         wfRestoreWarnings();
3026 }
3027
3028 /**
3029  * Get an object from the precompiled serialized directory
3030  *
3031  * @param $name String
3032  * @return Mixed: the variable on success, false on failure
3033  */
3034 function wfGetPrecompiledData( $name ) {
3035         global $IP;
3036
3037         $file = "$IP/serialized/$name";
3038         if ( file_exists( $file ) ) {
3039                 $blob = file_get_contents( $file );
3040                 if ( $blob ) {
3041                         return unserialize( $blob );
3042                 }
3043         }
3044         return false;
3045 }
3046
3047 /**
3048  * Get a cache key
3049  *
3050  * @param varargs
3051  * @return String
3052  */
3053 function wfMemcKey( /*... */ ) {
3054         $args = func_get_args();
3055         $key = wfWikiID() . ':' . implode( ':', $args );
3056         $key = str_replace( ' ', '_', $key );
3057         return $key;
3058 }
3059
3060 /**
3061  * Get a cache key for a foreign DB
3062  *
3063  * @param $db String
3064  * @param $prefix String
3065  * @param varargs String
3066  * @return String
3067  */
3068 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3069         $args = array_slice( func_get_args(), 2 );
3070         if ( $prefix ) {
3071                 $key = "$db-$prefix:" . implode( ':', $args );
3072         } else {
3073                 $key = $db . ':' . implode( ':', $args );
3074         }
3075         return $key;
3076 }
3077
3078 /**
3079  * Get an ASCII string identifying this wiki
3080  * This is used as a prefix in memcached keys
3081  *
3082  * @return String
3083  */
3084 function wfWikiID() {
3085         global $wgDBprefix, $wgDBname;
3086         if ( $wgDBprefix ) {
3087                 return "$wgDBname-$wgDBprefix";
3088         } else {
3089                 return $wgDBname;
3090         }
3091 }
3092
3093 /**
3094  * Split a wiki ID into DB name and table prefix
3095  *
3096  * @param $wiki String
3097  * @param $bits String
3098  */
3099 function wfSplitWikiID( $wiki ) {
3100         $bits = explode( '-', $wiki, 2 );
3101         if ( count( $bits ) < 2 ) {
3102                 $bits[] = '';
3103         }
3104         return $bits;
3105 }
3106
3107 /**
3108  * Get a Database object.
3109  *
3110  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3111  *            master (for write queries), DB_SLAVE for potentially lagged read
3112  *            queries, or an integer >= 0 for a particular server.
3113  *
3114  * @param $groups Mixed: query groups. An array of group names that this query
3115  *                belongs to. May contain a single string if the query is only
3116  *                in one group.
3117  *
3118  * @param $wiki String: the wiki ID, or false for the current wiki
3119  *
3120  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3121  * will always return the same object, unless the underlying connection or load
3122  * balancer is manually destroyed.
3123  *
3124  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3125  * updater to ensure that a proper database is being updated.
3126  *
3127  * @return DatabaseBase
3128  */
3129 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3130         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3131 }
3132
3133 /**
3134  * Get a load balancer object.
3135  *
3136  * @param $wiki String: wiki ID, or false for the current wiki
3137  * @return LoadBalancer
3138  */
3139 function wfGetLB( $wiki = false ) {
3140         return wfGetLBFactory()->getMainLB( $wiki );
3141 }
3142
3143 /**
3144  * Get the load balancer factory object
3145  *
3146  * @return LBFactory
3147  */
3148 function &wfGetLBFactory() {
3149         return LBFactory::singleton();
3150 }
3151
3152 /**
3153  * Find a file.
3154  * Shortcut for RepoGroup::singleton()->findFile()
3155  *
3156  * @param $title String or Title object
3157  * @param $options Associative array of options:
3158  *     time:           requested time for an archived image, or false for the
3159  *                     current version. An image object will be returned which was
3160  *                     created at the specified time.
3161  *
3162  *     ignoreRedirect: If true, do not follow file redirects
3163  *
3164  *     private:        If true, return restricted (deleted) files if the current
3165  *                     user is allowed to view them. Otherwise, such files will not
3166  *                     be found.
3167  *
3168  *     bypassCache:    If true, do not use the process-local cache of File objects
3169  *
3170  * @return File, or false if the file does not exist
3171  */
3172 function wfFindFile( $title, $options = array() ) {
3173         return RepoGroup::singleton()->findFile( $title, $options );
3174 }
3175
3176 /**
3177  * Get an object referring to a locally registered file.
3178  * Returns a valid placeholder object if the file does not exist.
3179  *
3180  * @param $title Title or String
3181  * @return File, or null if passed an invalid Title
3182  */
3183 function wfLocalFile( $title ) {
3184         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3185 }
3186
3187 /**
3188  * Should low-performance queries be disabled?
3189  *
3190  * @return Boolean
3191  * @codeCoverageIgnore
3192  */
3193 function wfQueriesMustScale() {
3194         global $wgMiserMode;
3195         return $wgMiserMode
3196                 || ( SiteStats::pages() > 100000
3197                 && SiteStats::edits() > 1000000
3198                 && SiteStats::users() > 10000 );
3199 }
3200
3201 /**
3202  * Get the path to a specified script file, respecting file
3203  * extensions; this is a wrapper around $wgScriptExtension etc.
3204  *
3205  * @param $script String: script filename, sans extension
3206  * @return String
3207  */
3208 function wfScript( $script = 'index' ) {
3209         global $wgScriptPath, $wgScriptExtension;
3210         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3211 }
3212
3213 /**
3214  * Get the script URL.
3215  *
3216  * @return script URL
3217  */
3218 function wfGetScriptUrl() {
3219         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3220                 #
3221                 # as it was called, minus the query string.
3222                 #
3223                 # Some sites use Apache rewrite rules to handle subdomains,
3224                 # and have PHP set up in a weird way that causes PHP_SELF
3225                 # to contain the rewritten URL instead of the one that the
3226                 # outside world sees.
3227                 #
3228                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3229                 # provides containing the "before" URL.
3230                 return $_SERVER['SCRIPT_NAME'];
3231         } else {
3232                 return $_SERVER['URL'];
3233         }
3234 }
3235
3236 /**
3237  * Convenience function converts boolean values into "true"
3238  * or "false" (string) values
3239  *
3240  * @param $value Boolean
3241  * @return String
3242  */
3243 function wfBoolToStr( $value ) {
3244         return $value ? 'true' : 'false';
3245 }
3246
3247 /**
3248  * Load an extension messages file
3249  *
3250  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3251  * @codeCoverageIgnore
3252  */
3253 function wfLoadExtensionMessages() {
3254         wfDeprecated( __FUNCTION__ );
3255 }
3256
3257 /**
3258  * Get a platform-independent path to the null file, e.g. /dev/null
3259  *
3260  * @return string
3261  */
3262 function wfGetNull() {
3263         return wfIsWindows()
3264                 ? 'NUL'
3265                 : '/dev/null';
3266 }
3267
3268 /**
3269  * Throws a warning that $function is deprecated
3270  *
3271  * @param $function String
3272  * @return null
3273  */
3274 function wfDeprecated( $function ) {
3275         static $functionsWarned = array();
3276         if ( !isset( $functionsWarned[$function] ) ) {
3277                 $functionsWarned[$function] = true;
3278                 wfWarn( "Use of $function is deprecated.", 2 );
3279         }
3280 }
3281
3282 /**
3283  * Send a warning either to the debug log or in a PHP error depending on
3284  * $wgDevelopmentWarnings
3285  *
3286  * @param $msg String: message to send
3287  * @param $callerOffset Integer: number of items to go back in the backtrace to
3288  *        find the correct caller (1 = function calling wfWarn, ...)
3289  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3290  *        is true
3291  */
3292 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3293         global $wgDevelopmentWarnings;
3294
3295         $callers = wfDebugBacktrace();
3296         if ( isset( $callers[$callerOffset + 1] ) ) {
3297                 $callerfunc = $callers[$callerOffset + 1];
3298                 $callerfile = $callers[$callerOffset];
3299                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3300                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3301                 } else {
3302                         $file = '(internal function)';
3303                 }
3304                 $func = '';
3305                 if ( isset( $callerfunc['class'] ) ) {
3306                         $func .= $callerfunc['class'] . '::';
3307                 }
3308                 if ( isset( $callerfunc['function'] ) ) {
3309                         $func .= $callerfunc['function'];
3310                 }
3311                 $msg .= " [Called from $func in $file]";
3312         }
3313
3314         if ( $wgDevelopmentWarnings ) {
3315                 trigger_error( $msg, $level );
3316         } else {
3317                 wfDebug( "$msg\n" );
3318         }
3319 }
3320
3321 /**
3322  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3323  * and waiting for it to go down, this waits for the slaves to catch up to the
3324  * master position. Use this when updating very large numbers of rows, as
3325  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3326  * a no-op if there are no slaves.
3327  *
3328  * @param $maxLag Integer (deprecated)
3329  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3330  * @return null
3331  */
3332 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3333         $lb = wfGetLB( $wiki );
3334         // bug 27975 - Don't try to wait for slaves if there are none
3335         // Prevents permission error when getting master position
3336         if ( $lb->getServerCount() > 1 ) {
3337                 $dbw = $lb->getConnection( DB_MASTER );
3338                 $pos = $dbw->getMasterPos();
3339                 $lb->waitForAll( $pos );
3340         }
3341 }
3342
3343 /**
3344  * Used to be used for outputting text in the installer/updater
3345  * @deprecated since 1.18, warnings in 1.19, remove in 1.20
3346  */
3347 function wfOut( $s ) {
3348         wfDeprecated( __METHOD__ );
3349         global $wgCommandLineMode;
3350         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3351                 echo $s;
3352         } else {
3353                 echo htmlspecialchars( $s );
3354         }
3355         flush();
3356 }
3357
3358 /**
3359  * Count down from $n to zero on the terminal, with a one-second pause
3360  * between showing each number. For use in command-line scripts.
3361  * @codeCoverageIgnore
3362  */
3363 function wfCountDown( $n ) {
3364         for ( $i = $n; $i >= 0; $i-- ) {
3365                 if ( $i != $n ) {
3366                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3367                 }
3368                 echo $i;
3369                 flush();
3370                 if ( $i ) {
3371                         sleep( 1 );
3372                 }
3373         }
3374         echo "\n";
3375 }
3376
3377 /**
3378  * Generate a random 32-character hexadecimal token.
3379  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3380  *              characters before hashing.
3381  * @return string
3382  * @codeCoverageIgnore
3383  */
3384 function wfGenerateToken( $salt = '' ) {
3385         $salt = serialize( $salt );
3386         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3387 }
3388
3389 /**
3390  * Replace all invalid characters with -
3391  *
3392  * @param $name Mixed: filename to process
3393  * @return String
3394  */
3395 function wfStripIllegalFilenameChars( $name ) {
3396         global $wgIllegalFileChars;
3397         $name = wfBaseName( $name );
3398         $name = preg_replace(
3399                 "/[^" . Title::legalChars() . "]" .
3400                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3401                         "/",
3402                 '-',
3403                 $name
3404         );
3405         return $name;
3406 }
3407
3408 /**
3409  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3410  *
3411  * @return Integer value memory was set to.
3412  */
3413 function wfMemoryLimit() {
3414         global $wgMemoryLimit;
3415         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3416         if( $memlimit != -1 ) {
3417                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3418                 if( $conflimit == -1 ) {
3419                         wfDebug( "Removing PHP's memory limit\n" );
3420                         wfSuppressWarnings();
3421                         ini_set( 'memory_limit', $conflimit );
3422                         wfRestoreWarnings();
3423                         return $conflimit;
3424                 } elseif ( $conflimit > $memlimit ) {
3425                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3426                         wfSuppressWarnings();
3427                         ini_set( 'memory_limit', $conflimit );
3428                         wfRestoreWarnings();
3429                         return $conflimit;
3430                 }
3431         }
3432         return $memlimit;
3433 }
3434
3435 /**
3436  * Converts shorthand byte notation to integer form
3437  *
3438  * @param $string String
3439  * @return Integer
3440  */
3441 function wfShorthandToInteger( $string = '' ) {
3442         $string = trim( $string );
3443         if( $string === '' ) {
3444                 return -1;
3445         }
3446         $last = $string[strlen( $string ) - 1];
3447         $val = intval( $string );
3448         switch( $last ) {
3449                 case 'g':
3450                 case 'G':
3451                         $val *= 1024;
3452                         // break intentionally missing
3453                 case 'm':
3454                 case 'M':
3455                         $val *= 1024;
3456                         // break intentionally missing
3457                 case 'k':
3458                 case 'K':
3459                         $val *= 1024;
3460         }
3461
3462         return $val;
3463 }
3464
3465 /**
3466  * Get the normalised IETF language tag
3467  * See unit test for examples.
3468  *
3469  * @param $code String: The language code.
3470  * @return $langCode String: The language code which complying with BCP 47 standards.
3471  */
3472 function wfBCP47( $code ) {
3473         $codeSegment = explode( '-', $code );
3474         $codeBCP = array();
3475         foreach ( $codeSegment as $segNo => $seg ) {
3476                 if ( count( $codeSegment ) > 0 ) {
3477                         // when previous segment is x, it is a private segment and should be lc
3478                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3479                                 $codeBCP[$segNo] = strtolower( $seg );
3480                         // ISO 3166 country code
3481                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3482                                 $codeBCP[$segNo] = strtoupper( $seg );
3483                         // ISO 15924 script code
3484                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3485                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3486                         // Use lowercase for other cases
3487                         } else {
3488                                 $codeBCP[$segNo] = strtolower( $seg );
3489                         }
3490                 } else {
3491                 // Use lowercase for single segment
3492                         $codeBCP[$segNo] = strtolower( $seg );
3493                 }
3494         }
3495         $langCode = implode( '-', $codeBCP );
3496         return $langCode;
3497 }
3498
3499 /**
3500  * Get a cache object.
3501  *
3502  * @param integer $inputType Cache type, one the the CACHE_* constants.
3503  * @return BagOStuff
3504  */
3505 function wfGetCache( $inputType ) {
3506         return ObjectCache::getInstance( $inputType );
3507 }
3508
3509 /**
3510  * Get the main cache object
3511  *
3512  * @return BagOStuff
3513  */
3514 function wfGetMainCache() {
3515         global $wgMainCacheType;
3516         return ObjectCache::getInstance( $wgMainCacheType );
3517 }
3518
3519 /**
3520  * Get the cache object used by the message cache
3521  *
3522  * @return BagOStuff
3523  */
3524 function wfGetMessageCacheStorage() {
3525         global $wgMessageCacheType;
3526         return ObjectCache::getInstance( $wgMessageCacheType );
3527 }
3528
3529 /**
3530  * Get the cache object used by the parser cache
3531  *
3532  * @return BagOStuff
3533  */
3534 function wfGetParserCacheStorage() {
3535         global $wgParserCacheType;
3536         return ObjectCache::getInstance( $wgParserCacheType );
3537 }
3538