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
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y') )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $needle ) ) {
 298                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 299                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 300                         $needle[] = '%3A';
 301                 }
 302         }
 303
 304         $s = urlencode( $s );
 305         $s = str_ireplace(
 306                 $needle,
 307                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 308                 $s
 309         );
 310
 311         return $s;
 312 }
 313
 314 /**
 315  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 316  * In normal operation this is a NOP.
 317  *
 318  * Controlling globals:
 319  * $wgDebugLogFile - points to the log file
 320  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 321  * $wgDebugRawPage - if false, 'load.php' hits will not result in debug output.
 322  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 323  *
 324  * @param $text String
 325  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 326  */
 327 function wfDebug( $text, $logonly = false ) {
 328         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 329         global $wgDebugLogPrefix, $wgShowDebug;
 330
 331         static $cache = array(); // Cache of unoutputted messages
 332         $text = wfDebugTimer() . $text;
 333
 334         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 335                 return;
 336         }
 337
 338         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 339                 $cache[] = $text;
 340
 341                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 342                         // add the message and any cached messages to the output
 343                         array_map( array( $wgOut, 'debug' ), $cache );
 344                         $cache = array();
 345                 }
 346         }
 347         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 348                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 349                         # Strip unprintables; they can switch terminal modes when binary data
 350                         # gets dumped, which is pretty annoying.
 351                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 352                         $text = $wgDebugLogPrefix . $text;
 353                         wfErrorLog( $text, $wgDebugLogFile );
 354                 }
 355         }
 356 }
 357
 358 /**
 359  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 360  */
 361 function wfIsDebugRawPage() {
 362         static $cache;
 363         if ( $cache !== null ) {
 364                 return $cache;
 365         }
 366
 367         if(     isset( $_SERVER['SCRIPT_NAME'] )
 368                 && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php' )
 369         {
 370                 $cache = true;
 371         } else {
 372                 $cache = false;
 373         }
 374         return $cache;
 375 }
 376
 377 /**
 378  * Get microsecond timestamps for debug logs
 379  *
 380  * @return string
 381  */
 382 function wfDebugTimer() {
 383         global $wgDebugTimestamps;
 384         if ( !$wgDebugTimestamps ) {
 385                 return '';
 386         }
 387         static $start = null;
 388
 389         if ( $start === null ) {
 390                 $start = microtime( true );
 391                 $prefix = "\n$start";
 392         } else {
 393                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 394         }
 395
 396         return $prefix . '  ';
 397 }
 398
 399 /**
 400  * Send a line giving PHP memory usage.
 401  *
 402  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 403  */
 404 function wfDebugMem( $exact = false ) {
 405         $mem = memory_get_usage();
 406         if( !$exact ) {
 407                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 408         } else {
 409                 $mem .= ' bytes';
 410         }
 411         wfDebug( "Memory usage: $mem\n" );
 412 }
 413
 414 /**
 415  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 416  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 417  *
 418  * @param $logGroup String
 419  * @param $text String
 420  * @param $public Bool: whether to log the event in the public log if no private
 421  *                     log file is specified, (default true)
 422  */
 423 function wfDebugLog( $logGroup, $text, $public = true ) {
 424         global $wgDebugLogGroups, $wgShowHostnames;
 425         $text = trim( $text ) . "\n";
 426         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 427                 $time = wfTimestamp( TS_DB );
 428                 $wiki = wfWikiID();
 429                 if ( $wgShowHostnames ) {
 430                         $host = wfHostname();
 431                 } else {
 432                         $host = '';
 433                 }
 434                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 435                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 436                 }
 437         } elseif ( $public === true ) {
 438                 wfDebug( $text, true );
 439         }
 440 }
 441
 442 /**
 443  * Log for database errors
 444  *
 445  * @param $text String: database error message.
 446  */
 447 function wfLogDBError( $text ) {
 448         global $wgDBerrorLog, $wgDBname;
 449         if ( $wgDBerrorLog ) {
 450                 $host = trim(`hostname`);
 451                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 452                 wfErrorLog( $text, $wgDBerrorLog );
 453         }
 454 }
 455
 456 /**
 457  * Log to a file without getting "file size exceeded" signals.
 458  *
 459  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 460  * send lines to the specified port, prefixed by the specified prefix and a space.
 461  *
 462  * @param $text String
 463  * @param $file String filename
 464  */
 465 function wfErrorLog( $text, $file ) {
 466         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 467                 # Needs the sockets extension
 468                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 469                         // IPv6 bracketed host
 470                         $host = $m[2];
 471                         $port = intval( $m[3] );
 472                         $prefix = isset( $m[4] ) ? $m[4] : false;
 473                         $domain = AF_INET6;
 474                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 475                         $host = $m[2];
 476                         if ( !IP::isIPv4( $host ) ) {
 477                                 $host = gethostbyname( $host );
 478                         }
 479                         $port = intval( $m[3] );
 480                         $prefix = isset( $m[4] ) ? $m[4] : false;
 481                         $domain = AF_INET;
 482                 } else {
 483                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 484                 }
 485
 486                 // Clean it up for the multiplexer
 487                 if ( strval( $prefix ) !== '' ) {
 488                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 489
 490                         // Limit to 64KB
 491                         if ( strlen( $text ) > 65534 ) {
 492                                 $text = substr( $text, 0, 65534 );
 493                         }
 494
 495                         if ( substr( $text, -1 ) != "\n" ) {
 496                                 $text .= "\n";
 497                         }
 498                 } elseif ( strlen( $text ) > 65535 ) {
 499                         $text = substr( $text, 0, 65535 );
 500                 }
 501
 502                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 503                 if ( !$sock ) {
 504                         return;
 505                 }
 506                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 507                 socket_close( $sock );
 508         } else {
 509                 wfSuppressWarnings();
 510                 $exists = file_exists( $file );
 511                 $size = $exists ? filesize( $file ) : false;
 512                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 513                         file_put_contents( $file, $text, FILE_APPEND );
 514                 }
 515                 wfRestoreWarnings();
 516         }
 517 }
 518
 519 /**
 520  * @todo document
 521  */
 522 function wfLogProfilingData() {
 523         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 524         global $wgProfileLimit, $wgUser;
 525
 526         $profiler = Profiler::instance();
 527
 528         # Profiling must actually be enabled...
 529         if ( $profiler->isStub() ) {
 530                 return;
 531         }
 532
 533         // Get total page request time and only show pages that longer than
 534         // $wgProfileLimit time (default is 0)
 535         $now = wfTime();
 536         $elapsed = $now - $wgRequestTime;
 537         if ( $elapsed <= $wgProfileLimit ) {
 538                 return;
 539         }
 540
 541         $profiler->logData();
 542
 543         // Check whether this should be logged in the debug file.
 544         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 545                 return;
 546         }
 547
 548         $forward = '';
 549         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 550                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 551         }
 552         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 553                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 554         }
 555         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 556                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 557         }
 558         if ( $forward ) {
 559                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 560         }
 561         // Don't load $wgUser at this late stage just for statistics purposes
 562         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 563         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 564                 $forward .= ' anon';
 565         }
 566         $log = sprintf( "%s\t%04.3f\t%s\n",
 567                 gmdate( 'YmdHis' ), $elapsed,
 568                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 569
 570         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 571 }
 572
 573 /**
 574  * Check if the wiki read-only lock file is present. This can be used to lock
 575  * off editing functions, but doesn't guarantee that the database will not be
 576  * modified.
 577  *
 578  * @return bool
 579  */
 580 function wfReadOnly() {
 581         global $wgReadOnlyFile, $wgReadOnly;
 582
 583         if ( !is_null( $wgReadOnly ) ) {
 584                 return (bool)$wgReadOnly;
 585         }
 586         if ( $wgReadOnlyFile == '' ) {
 587                 return false;
 588         }
 589         // Set $wgReadOnly for faster access next time
 590         if ( is_file( $wgReadOnlyFile ) ) {
 591                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 592         } else {
 593                 $wgReadOnly = false;
 594         }
 595         return (bool)$wgReadOnly;
 596 }
 597
 598 function wfReadOnlyReason() {
 599         global $wgReadOnly;
 600         wfReadOnly();
 601         return $wgReadOnly;
 602 }
 603
 604 /**
 605  * Return a Language object from $langcode
 606  *
 607  * @param $langcode Mixed: either:
 608  *                  - a Language object
 609  *                  - code of the language to get the message for, if it is
 610  *                    a valid code create a language for that language, if
 611  *                    it is a string but not a valid code then make a basic
 612  *                    language object
 613  *                  - a boolean: if it's false then use the current users
 614  *                    language (as a fallback for the old parameter
 615  *                    functionality), or if it is true then use the wikis
 616  * @return Language object
 617  */
 618 function wfGetLangObj( $langcode = false ) {
 619         # Identify which language to get or create a language object for.
 620         # Using is_object here due to Stub objects.
 621         if( is_object( $langcode ) ) {
 622                 # Great, we already have the object (hopefully)!
 623                 return $langcode;
 624         }
 625
 626         global $wgContLang, $wgLanguageCode;
 627         if( $langcode === true || $langcode === $wgLanguageCode ) {
 628                 # $langcode is the language code of the wikis content language object.
 629                 # or it is a boolean and value is true
 630                 return $wgContLang;
 631         }
 632
 633         global $wgLang;
 634         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 635                 # $langcode is the language code of user language object.
 636                 # or it was a boolean and value is false
 637                 return $wgLang;
 638         }
 639
 640         $validCodes = array_keys( Language::getLanguageNames() );
 641         if( in_array( $langcode, $validCodes ) ) {
 642                 # $langcode corresponds to a valid language.
 643                 return Language::factory( $langcode );
 644         }
 645
 646         # $langcode is a string, but not a valid language code; use content language.
 647         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 648         return $wgContLang;
 649 }
 650
 651 /**
 652  * Use this instead of $wgContLang, when working with user interface.
 653  * User interface is currently hard coded according to wiki content language
 654  * in many ways, especially regarding to text direction. There is lots stuff
 655  * to fix, hence this function to keep the old behaviour unless the global
 656  * $wgBetterDirectionality is enabled (or removed when everything works).
 657  *
 658  * @return Language
 659  */
 660 function wfUILang() {
 661         global $wgBetterDirectionality;
 662         return wfGetLangObj( !$wgBetterDirectionality );
 663 }
 664
 665 /**
 666  * This is the new function for getting translated interface messages.
 667  * See the Message class for documentation how to use them.
 668  * The intention is that this function replaces all old wfMsg* functions.
 669  * @param $key \string Message key.
 670  * Varargs: normal message parameters.
 671  * @return Message
 672  * @since 1.17
 673  */
 674 function wfMessage( $key /*...*/) {
 675         $params = func_get_args();
 676         array_shift( $params );
 677         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 678                 $params = $params[0];
 679         }
 680         return new Message( $key, $params );
 681 }
 682
 683 /**
 684  * This function accepts multiple message keys and returns a message instance
 685  * for the first message which is non-empty. If all messages are empty then an
 686  * instance of the first message key is returned.
 687  * @param varargs: message keys
 688  * @return Message
 689  * @since 1.18
 690  */
 691 function wfMessageFallback( /*...*/ ) {
 692         $args = func_get_args();
 693         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
 694 }
 695
 696 /**
 697  * Get a message from anywhere, for the current user language.
 698  *
 699  * Use wfMsgForContent() instead if the message should NOT
 700  * change depending on the user preferences.
 701  *
 702  * @param $key String: lookup key for the message, usually
 703  *    defined in languages/Language.php
 704  *
 705  * This function also takes extra optional parameters (not
 706  * shown in the function definition), which can be used to
 707  * insert variable text into the predefined message.
 708  * @return String
 709  */
 710 function wfMsg( $key ) {
 711         $args = func_get_args();
 712         array_shift( $args );
 713         return wfMsgReal( $key, $args, true );
 714 }
 715
 716 /**
 717  * Same as above except doesn't transform the message
 718  *
 719  * @param $key String
 720  * @return String
 721  */
 722 function wfMsgNoTrans( $key ) {
 723         $args = func_get_args();
 724         array_shift( $args );
 725         return wfMsgReal( $key, $args, true, false, false );
 726 }
 727
 728 /**
 729  * Get a message from anywhere, for the current global language
 730  * set with $wgLanguageCode.
 731  *
 732  * Use this if the message should NOT change dependent on the
 733  * language set in the user's preferences. This is the case for
 734  * most text written into logs, as well as link targets (such as
 735  * the name of the copyright policy page). Link titles, on the
 736  * other hand, should be shown in the UI language.
 737  *
 738  * Note that MediaWiki allows users to change the user interface
 739  * language in their preferences, but a single installation
 740  * typically only contains content in one language.
 741  *
 742  * Be wary of this distinction: If you use wfMsg() where you should
 743  * use wfMsgForContent(), a user of the software may have to
 744  * customize potentially hundreds of messages in
 745  * order to, e.g., fix a link in every possible language.
 746  *
 747  * @param $key String: lookup key for the message, usually
 748  *     defined in languages/Language.php
 749  * @return String
 750  */
 751 function wfMsgForContent( $key ) {
 752         global $wgForceUIMsgAsContentMsg;
 753         $args = func_get_args();
 754         array_shift( $args );
 755         $forcontent = true;
 756         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 757                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 758         {
 759                 $forcontent = false;
 760         }
 761         return wfMsgReal( $key, $args, true, $forcontent );
 762 }
 763
 764 /**
 765  * Same as above except doesn't transform the message
 766  *
 767  * @param $key String
 768  * @return String
 769  */
 770 function wfMsgForContentNoTrans( $key ) {
 771         global $wgForceUIMsgAsContentMsg;
 772         $args = func_get_args();
 773         array_shift( $args );
 774         $forcontent = true;
 775         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 776                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 777         {
 778                 $forcontent = false;
 779         }
 780         return wfMsgReal( $key, $args, true, $forcontent, false );
 781 }
 782
 783 /**
 784  * Get a message from the language file, for the UI elements
 785  *
 786  * @deprecated since 1.18; use wfMessage()
 787  */
 788 function wfMsgNoDB( $key ) {
 789         wfDeprecated( __FUNCTION__ );
 790         $args = func_get_args();
 791         array_shift( $args );
 792         return wfMsgReal( $key, $args, false );
 793 }
 794
 795 /**
 796  * Get a message from the language file, for the content
 797  *
 798  * @deprecated since 1.18; use wfMessage()
 799  */
 800 function wfMsgNoDBForContent( $key ) {
 801         wfDeprecated( __FUNCTION__ );
 802         global $wgForceUIMsgAsContentMsg;
 803         $args = func_get_args();
 804         array_shift( $args );
 805         $forcontent = true;
 806         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 807                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 808         {
 809                 $forcontent = false;
 810         }
 811         return wfMsgReal( $key, $args, false, $forcontent );
 812 }
 813
 814
 815 /**
 816  * Really get a message
 817  *
 818  * @param $key String: key to get.
 819  * @param $args
 820  * @param $useDB Boolean
 821  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 822  * @param $transform Boolean: Whether or not to transform the message.
 823  * @return String: the requested message.
 824  */
 825 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 826         wfProfileIn( __METHOD__ );
 827         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 828         $message = wfMsgReplaceArgs( $message, $args );
 829         wfProfileOut( __METHOD__ );
 830         return $message;
 831 }
 832
 833 /**
 834  * This function provides the message source for messages to be edited which are *not* stored in the database.
 835  *
 836  * @deprecated since 1.18; use wfMessage()
 837  * @param $key String
 838  */
 839 function wfMsgWeirdKey( $key ) {
 840         wfDeprecated( __FUNCTION__ );
 841         $source = wfMsgGetKey( $key, false, true, false );
 842         if ( wfEmptyMsg( $key ) ) {
 843                 return '';
 844         } else {
 845                 return $source;
 846         }
 847 }
 848
 849 /**
 850  * Fetch a message string value, but don't replace any keys yet.
 851  *
 852  * @param $key String
 853  * @param $useDB Bool
 854  * @param $langCode String: Code of the language to get the message for, or
 855  *                  behaves as a content language switch if it is a boolean.
 856  * @param $transform Boolean: whether to parse magic words, etc.
 857  * @return string
 858  */
 859 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 860         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 861
 862         $cache = MessageCache::singleton();
 863         $message = $cache->get( $key, $useDB, $langCode );
 864         if( $message === false ) {
 865                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 866         } elseif ( $transform ) {
 867                 $message = $cache->transform( $message );
 868         }
 869         return $message;
 870 }
 871
 872 /**
 873  * Replace message parameter keys on the given formatted output.
 874  *
 875  * @param $message String
 876  * @param $args Array
 877  * @return string
 878  * @private
 879  */
 880 function wfMsgReplaceArgs( $message, $args ) {
 881         # Fix windows line-endings
 882         # Some messages are split with explode("\n", $msg)
 883         $message = str_replace( "\r", '', $message );
 884
 885         // Replace arguments
 886         if ( count( $args ) ) {
 887                 if ( is_array( $args[0] ) ) {
 888                         $args = array_values( $args[0] );
 889                 }
 890                 $replacementKeys = array();
 891                 foreach( $args as $n => $param ) {
 892                         $replacementKeys['$' . ( $n + 1 )] = $param;
 893                 }
 894                 $message = strtr( $message, $replacementKeys );
 895         }
 896
 897         return $message;
 898 }
 899
 900 /**
 901  * Return an HTML-escaped version of a message.
 902  * Parameter replacements, if any, are done *after* the HTML-escaping,
 903  * so parameters may contain HTML (eg links or form controls). Be sure
 904  * to pre-escape them if you really do want plaintext, or just wrap
 905  * the whole thing in htmlspecialchars().
 906  *
 907  * @param $key String
 908  * @param string ... parameters
 909  * @return string
 910  */
 911 function wfMsgHtml( $key ) {
 912         $args = func_get_args();
 913         array_shift( $args );
 914         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 915 }
 916
 917 /**
 918  * Return an HTML version of message
 919  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 920  * so parameters may contain HTML (eg links or form controls). Be sure
 921  * to pre-escape them if you really do want plaintext, or just wrap
 922  * the whole thing in htmlspecialchars().
 923  *
 924  * @param $key String
 925  * @param string ... parameters
 926  * @return string
 927  */
 928 function wfMsgWikiHtml( $key ) {
 929         $args = func_get_args();
 930         array_shift( $args );
 931         return wfMsgReplaceArgs(
 932                 MessageCache::singleton()->parse( wfMsgGetKey( $key, true ), null, /* can't be set to false */ true )->getText(),
 933                 $args );
 934 }
 935
 936 /**
 937  * Returns message in the requested format
 938  * @param $key String: key of the message
 939  * @param $options Array: processing rules. Can take the following options:
 940  *   <i>parse</i>: parses wikitext to HTML
 941  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 942  *       p's added by parser or tidy
 943  *   <i>escape</i>: filters message through htmlspecialchars
 944  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 945  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 946  *   <i>parsemag</i>: transform the message using magic phrases
 947  *   <i>content</i>: fetch message for content language instead of interface
 948  * Also can accept a single associative argument, of the form 'language' => 'xx':
 949  *   <i>language</i>: Language object or language code to fetch message for
 950  *       (overriden by <i>content</i>).
 951  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 952  *
 953  * @return String
 954  */
 955 function wfMsgExt( $key, $options ) {
 956         $args = func_get_args();
 957         array_shift( $args );
 958         array_shift( $args );
 959         $options = (array)$options;
 960
 961         foreach( $options as $arrayKey => $option ) {
 962                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 963                         # An unknown index, neither numeric nor "language"
 964                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 965                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 966                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 967                 'replaceafter', 'parsemag', 'content' ) ) ) {
 968                         # A numeric index with unknown value
 969                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 970                 }
 971         }
 972
 973         if( in_array( 'content', $options, true ) ) {
 974                 $forContent = true;
 975                 $langCode = true;
 976                 $langCodeObj = null;
 977         } elseif( array_key_exists( 'language', $options ) ) {
 978                 $forContent = false;
 979                 $langCode = wfGetLangObj( $options['language'] );
 980                 $langCodeObj = $langCode;
 981         } else {
 982                 $forContent = false;
 983                 $langCode = false;
 984                 $langCodeObj = null;
 985         }
 986
 987         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 988
 989         if( !in_array( 'replaceafter', $options, true ) ) {
 990                 $string = wfMsgReplaceArgs( $string, $args );
 991         }
 992
 993         $messageCache = MessageCache::singleton();
 994         if( in_array( 'parse', $options, true ) ) {
 995                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
 996         } elseif ( in_array( 'parseinline', $options, true ) ) {
 997                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
 998                 $m = array();
 999                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1000                         $string = $m[1];
1001                 }
1002         } elseif ( in_array( 'parsemag', $options, true ) ) {
1003                 $string = $messageCache->transform( $string,
1004                                 !$forContent, $langCodeObj );
1005         }
1006
1007         if ( in_array( 'escape', $options, true ) ) {
1008                 $string = htmlspecialchars ( $string );
1009         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1010                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1011         }
1012
1013         if( in_array( 'replaceafter', $options, true ) ) {
1014                 $string = wfMsgReplaceArgs( $string, $args );
1015         }
1016
1017         return $string;
1018 }
1019
1020 /**
1021  * Since wfMsg() and co suck, they don't return false if the message key they
1022  * looked up didn't exist but a XHTML string, this function checks for the
1023  * nonexistance of messages by checking the MessageCache::get() result directly.
1024  *
1025  * @param $key      String: the message key looked up
1026  * @return Boolean True if the message *doesn't* exist.
1027  */
1028 function wfEmptyMsg( $key ) {
1029         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1030 }
1031
1032 /**
1033  * Print an error message and die, returning nonzero to the shell if any.  Plain die()
1034  * fails to return nonzero to the shell if you pass a string.  Entry points may customise
1035  * this function to return a prettier error message, but implementations must not assume
1036  * access to any of the usual MediaWiki infrastructure (AutoLoader, localisation, database,
1037  * etc).  This should not be called directly once $wgFullyInitialised is set; instead,
1038  * throw an exception and let Exception.php handle whether or not it's possible to show
1039  * a prettier error.
1040  *
1041  * @param $msg String
1042  */
1043 if( !function_exists( 'wfDie' ) ){
1044         function wfDie( $msg = '' ) {
1045                 echo $msg;
1046                 die( 1 );
1047         }
1048 }
1049
1050 /**
1051  * Throw a debugging exception. This function previously once exited the process,
1052  * but now throws an exception instead, with similar results.
1053  *
1054  * @param $msg String: message shown when dieing.
1055  */
1056 function wfDebugDieBacktrace( $msg = '' ) {
1057         throw new MWException( $msg );
1058 }
1059
1060 /**
1061  * Fetch server name for use in error reporting etc.
1062  * Use real server name if available, so we know which machine
1063  * in a server farm generated the current page.
1064  *
1065  * @return string
1066  */
1067 function wfHostname() {
1068         static $host;
1069         if ( is_null( $host ) ) {
1070                 if ( function_exists( 'posix_uname' ) ) {
1071                         // This function not present on Windows
1072                         $uname = @posix_uname();
1073                 } else {
1074                         $uname = false;
1075                 }
1076                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1077                         $host = $uname['nodename'];
1078                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1079                         # Windows computer name
1080                         $host = getenv( 'COMPUTERNAME' );
1081                 } else {
1082                         # This may be a virtual server.
1083                         $host = $_SERVER['SERVER_NAME'];
1084                 }
1085         }
1086         return $host;
1087 }
1088
1089 /**
1090  * Returns a HTML comment with the elapsed time since request.
1091  * This method has no side effects.
1092  *
1093  * @return string
1094  */
1095 function wfReportTime() {
1096         global $wgRequestTime, $wgShowHostnames;
1097
1098         $now = wfTime();
1099         $elapsed = $now - $wgRequestTime;
1100
1101         return $wgShowHostnames
1102                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1103                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1104 }
1105
1106 /**
1107  * Safety wrapper for debug_backtrace().
1108  *
1109  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1110  * murky circumstances, which may be triggered in part by stub objects
1111  * or other fancy talkin'.
1112  *
1113  * Will return an empty array if Zend Optimizer is detected or if
1114  * debug_backtrace is disabled, otherwise the output from
1115  * debug_backtrace() (trimmed).
1116  *
1117  * @return array of backtrace information
1118  */
1119 function wfDebugBacktrace() {
1120         static $disabled = null;
1121
1122         if( extension_loaded( 'Zend Optimizer' ) ) {
1123                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1124                 return array();
1125         }
1126
1127         if ( is_null( $disabled ) ) {
1128                 $disabled = false;
1129                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1130                 $functions = array_map( 'trim', $functions );
1131                 $functions = array_map( 'strtolower', $functions );
1132                 if ( in_array( 'debug_backtrace', $functions ) ) {
1133                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1134                         $disabled = true;
1135                 }
1136         }
1137         if ( $disabled ) {
1138                 return array();
1139         }
1140
1141         return array_slice( debug_backtrace(), 1 );
1142 }
1143
1144 /**
1145  * Get a debug backtrace as a string
1146  *
1147  * @return string
1148  */
1149 function wfBacktrace() {
1150         global $wgCommandLineMode;
1151
1152         if ( $wgCommandLineMode ) {
1153                 $msg = '';
1154         } else {
1155                 $msg = "<ul>\n";
1156         }
1157         $backtrace = wfDebugBacktrace();
1158         foreach( $backtrace as $call ) {
1159                 if( isset( $call['file'] ) ) {
1160                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1161                         $file = $f[count( $f ) - 1];
1162                 } else {
1163                         $file = '-';
1164                 }
1165                 if( isset( $call['line'] ) ) {
1166                         $line = $call['line'];
1167                 } else {
1168                         $line = '-';
1169                 }
1170                 if ( $wgCommandLineMode ) {
1171                         $msg .= "$file line $line calls ";
1172                 } else {
1173                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1174                 }
1175                 if( !empty( $call['class'] ) ) {
1176                         $msg .= $call['class'] . '::';
1177                 }
1178                 $msg .= $call['function'] . '()';
1179
1180                 if ( $wgCommandLineMode ) {
1181                         $msg .= "\n";
1182                 } else {
1183                         $msg .= "</li>\n";
1184                 }
1185         }
1186         if ( $wgCommandLineMode ) {
1187                 $msg .= "\n";
1188         } else {
1189                 $msg .= "</ul>\n";
1190         }
1191
1192         return $msg;
1193 }
1194
1195 /**
1196  * Get the name of the function which called this function
1197  *
1198  * @param $level Int
1199  * @return Bool|string
1200  */
1201 function wfGetCaller( $level = 2 ) {
1202         $backtrace = wfDebugBacktrace();
1203         if ( isset( $backtrace[$level] ) ) {
1204                 return wfFormatStackFrame( $backtrace[$level] );
1205         } else {
1206                 $caller = 'unknown';
1207         }
1208         return $caller;
1209 }
1210
1211 /**
1212  * Return a string consisting of callers in the stack. Useful sometimes
1213  * for profiling specific points.
1214  *
1215  * @param $limit The maximum depth of the stack frame to return, or false for
1216  *               the entire stack.
1217  * @return String
1218  */
1219 function wfGetAllCallers( $limit = 3 ) {
1220         $trace = array_reverse( wfDebugBacktrace() );
1221         if ( !$limit || $limit > count( $trace ) - 1 ) {
1222                 $limit = count( $trace ) - 1;
1223         }
1224         $trace = array_slice( $trace, -$limit - 1, $limit );
1225         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1226 }
1227
1228 /**
1229  * Return a string representation of frame
1230  *
1231  * @param $frame Array
1232  * @return Bool
1233  */
1234 function wfFormatStackFrame( $frame ) {
1235         return isset( $frame['class'] ) ?
1236                 $frame['class'] . '::' . $frame['function'] :
1237                 $frame['function'];
1238 }
1239
1240
1241 /* Some generic result counters, pulled out of SearchEngine */
1242
1243
1244 /**
1245  * @todo document
1246  *
1247  * @param $offset Int
1248  * @param $limit Int
1249  * @return String
1250  */
1251 function wfShowingResults( $offset, $limit ) {
1252         global $wgLang;
1253         return wfMsgExt(
1254                 'showingresults',
1255                 array( 'parseinline' ),
1256                 $wgLang->formatNum( $limit ),
1257                 $wgLang->formatNum( $offset + 1 )
1258         );
1259 }
1260
1261 /**
1262  * @todo document
1263  *
1264  * @param $offset Int
1265  * @param $limit Int
1266  * @param $num Int
1267  * @return String
1268  */
1269 function wfShowingResultsNum( $offset, $limit, $num ) {
1270         global $wgLang;
1271         return wfMsgExt(
1272                 'showingresultsnum',
1273                 array( 'parseinline' ),
1274                 $wgLang->formatNum( $limit ),
1275                 $wgLang->formatNum( $offset + 1 ),
1276                 $wgLang->formatNum( $num )
1277         );
1278 }
1279
1280 /**
1281  * Generate (prev x| next x) (20|50|100...) type links for paging
1282  *
1283  * @param $offset String
1284  * @param $limit Integer
1285  * @param $link String
1286  * @param $query String: optional URL query parameter string
1287  * @param $atend Bool: optional param for specified if this is the last page
1288  * @return String
1289  */
1290 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1291         global $wgLang;
1292         $fmtLimit = $wgLang->formatNum( $limit );
1293         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1294         # Get prev/next link display text
1295         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1296         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1297         # Get prev/next link title text
1298         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1299         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1300         # Fetch the title object
1301         if( is_object( $link ) ) {
1302                 $title =& $link;
1303         } else {
1304                 $title = Title::newFromText( $link );
1305                 if( is_null( $title ) ) {
1306                         return false;
1307                 }
1308         }
1309         # Make 'previous' link
1310         if( 0 != $offset ) {
1311                 $po = $offset - $limit;
1312                 $po = max( $po, 0 );
1313                 $q = "limit={$limit}&offset={$po}";
1314                 if( $query != '' ) {
1315                         $q .= '&' . $query;
1316                 }
1317                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1318         } else {
1319                 $plink = $prev;
1320         }
1321         # Make 'next' link
1322         $no = $offset + $limit;
1323         $q = "limit={$limit}&offset={$no}";
1324         if( $query != '' ) {
1325                 $q .= '&' . $query;
1326         }
1327         if( $atend ) {
1328                 $nlink = $next;
1329         } else {
1330                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1331         }
1332         # Make links to set number of items per page
1333         $nums = $wgLang->pipeList( array(
1334                 wfNumLink( $offset, 20, $title, $query ),
1335                 wfNumLink( $offset, 50, $title, $query ),
1336                 wfNumLink( $offset, 100, $title, $query ),
1337                 wfNumLink( $offset, 250, $title, $query ),
1338                 wfNumLink( $offset, 500, $title, $query )
1339         ) );
1340         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1341 }
1342
1343 /**
1344  * Generate links for (20|50|100...) items-per-page links
1345  *
1346  * @param $offset String
1347  * @param $limit Integer
1348  * @param $title Title
1349  * @param $query String: optional URL query parameter string
1350  */
1351 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1352         global $wgLang;
1353         if( $query == '' ) {
1354                 $q = '';
1355         } else {
1356                 $q = $query.'&';
1357         }
1358         $q .= "limit={$limit}&offset={$offset}";
1359         $fmtLimit = $wgLang->formatNum( $limit );
1360         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1361         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1362         return $s;
1363 }
1364
1365 /**
1366  * @todo document
1367  * @todo FIXME: We may want to blacklist some broken browsers
1368  *
1369  * @param $force Bool
1370  * @return bool Whereas client accept gzip compression
1371  */
1372 function wfClientAcceptsGzip( $force = false ) {
1373         static $result = null;
1374         if ( $result === null || $force ) {
1375                 $result = false;
1376                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1377                         # @todo FIXME: We may want to blacklist some broken browsers
1378                         $m = array();
1379                         if( preg_match(
1380                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1381                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1382                                 $m )
1383                         )
1384                         {
1385                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1386                                         $result = false;
1387                                         return $result;
1388                                 }
1389                                 wfDebug( " accepts gzip\n" );
1390                                 $result = true;
1391                         }
1392                 }
1393         }
1394         return $result;
1395 }
1396
1397 /**
1398  * Obtain the offset and limit values from the request string;
1399  * used in special pages
1400  *
1401  * @param $deflimit Int default limit if none supplied
1402  * @param $optionname String Name of a user preference to check against
1403  * @return array
1404  *
1405  */
1406 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1407         global $wgRequest;
1408         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1409 }
1410
1411 /**
1412  * Escapes the given text so that it may be output using addWikiText()
1413  * without any linking, formatting, etc. making its way through. This
1414  * is achieved by substituting certain characters with HTML entities.
1415  * As required by the callers, <nowiki> is not used.
1416  *
1417  * @param $text String: text to be escaped
1418  * @return String
1419  */
1420 function wfEscapeWikiText( $text ) {
1421         $text = strtr( "\n$text", array(
1422                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1423                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1424                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1425                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1426                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1427                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1428         ) );
1429         return substr( $text, 1 );
1430 }
1431
1432 /**
1433  * Get the current unix timetstamp with microseconds.  Useful for profiling
1434  * @return Float
1435  */
1436 function wfTime() {
1437         return microtime( true );
1438 }
1439
1440 /**
1441  * Sets dest to source and returns the original value of dest
1442  * If source is NULL, it just returns the value, it doesn't set the variable
1443  * If force is true, it will set the value even if source is NULL
1444  *
1445  * @param $dest Mixed
1446  * @param $source Mixed
1447  * @param $force Bool
1448  * @return Mixed
1449  */
1450 function wfSetVar( &$dest, $source, $force = false ) {
1451         $temp = $dest;
1452         if ( !is_null( $source ) || $force ) {
1453                 $dest = $source;
1454         }
1455         return $temp;
1456 }
1457
1458 /**
1459  * As for wfSetVar except setting a bit
1460  *
1461  * @param $dest Int
1462  * @param $bit Int
1463  * @param $state Bool
1464  */
1465 function wfSetBit( &$dest, $bit, $state = true ) {
1466         $temp = (bool)( $dest & $bit );
1467         if ( !is_null( $state ) ) {
1468                 if ( $state ) {
1469                         $dest |= $bit;
1470                 } else {
1471                         $dest &= ~$bit;
1472                 }
1473         }
1474         return $temp;
1475 }
1476
1477 /**
1478  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1479  * "days=7&limit=100". Options in the first array override options in the second.
1480  * Options set to "" will not be output.
1481  *
1482  * @param $array1 Array( String|Array )
1483  * @param $array2 Array( String|Array )
1484  * @return String
1485  */
1486 function wfArrayToCGI( $array1, $array2 = null ) {
1487         if ( !is_null( $array2 ) ) {
1488                 $array1 = $array1 + $array2;
1489         }
1490
1491         $cgi = '';
1492         foreach ( $array1 as $key => $value ) {
1493                 if ( $value !== '' ) {
1494                         if ( $cgi != '' ) {
1495                                 $cgi .= '&';
1496                         }
1497                         if ( is_array( $value ) ) {
1498                                 $firstTime = true;
1499                                 foreach ( $value as $v ) {
1500                                         $cgi .= ( $firstTime ? '' : '&') .
1501                                                 urlencode( $key . '[]' ) . '=' .
1502                                                 urlencode( $v );
1503                                         $firstTime = false;
1504                                 }
1505                         } else {
1506                                 if ( is_object( $value ) ) {
1507                                         $value = $value->__toString();
1508                                 }
1509                                 $cgi .= urlencode( $key ) . '=' .
1510                                         urlencode( $value );
1511                         }
1512                 }
1513         }
1514         return $cgi;
1515 }
1516
1517 /**
1518  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1519  * its argument and returns the same string in array form.  This allows compa-
1520  * tibility with legacy functions that accept raw query strings instead of nice
1521  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1522  * valid query strings, or it will explode.
1523  *
1524  * @param $query String: query string
1525  * @return array Array version of input
1526  */
1527 function wfCgiToArray( $query ) {
1528         if( isset( $query[0] ) && $query[0] == '?' ) {
1529                 $query = substr( $query, 1 );
1530         }
1531         $bits = explode( '&', $query );
1532         $ret = array();
1533         foreach( $bits as $bit ) {
1534                 if( $bit === '' ) {
1535                         continue;
1536                 }
1537                 list( $key, $value ) = explode( '=', $bit );
1538                 $key = urldecode( $key );
1539                 $value = urldecode( $value );
1540                 $ret[$key] = $value;
1541         }
1542         return $ret;
1543 }
1544
1545 /**
1546  * Append a query string to an existing URL, which may or may not already
1547  * have query string parameters already. If so, they will be combined.
1548  *
1549  * @param $url String
1550  * @param $query Mixed: string or associative array
1551  * @return string
1552  */
1553 function wfAppendQuery( $url, $query ) {
1554         if ( is_array( $query ) ) {
1555                 $query = wfArrayToCGI( $query );
1556         }
1557         if( $query != '' ) {
1558                 if( false === strpos( $url, '?' ) ) {
1559                         $url .= '?';
1560                 } else {
1561                         $url .= '&';
1562                 }
1563                 $url .= $query;
1564         }
1565         return $url;
1566 }
1567
1568 /**
1569  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1570  * and $wgProto are correct.
1571  *
1572  * @todo this won't work with current-path-relative URLs
1573  * like "subdir/foo.html", etc.
1574  *
1575  * @param $url String: either fully-qualified or a local path + query
1576  * @return string Fully-qualified URL
1577  */
1578 function wfExpandUrl( $url ) {
1579         if( substr( $url, 0, 2 ) == '//' ) {
1580                 global $wgProto;
1581                 return $wgProto . ':' . $url;
1582         } elseif( substr( $url, 0, 1 ) == '/' ) {
1583                 global $wgServer;
1584                 return $wgServer . $url;
1585         } else {
1586                 return $url;
1587         }
1588 }
1589
1590 /**
1591  * Windows-compatible version of escapeshellarg()
1592  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1593  * function puts single quotes in regardless of OS.
1594  *
1595  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1596  * earlier distro releases of PHP)
1597  *
1598  * @param varargs
1599  * @return String
1600  */
1601 function wfEscapeShellArg( ) {
1602         wfInitShellLocale();
1603
1604         $args = func_get_args();
1605         $first = true;
1606         $retVal = '';
1607         foreach ( $args as $arg ) {
1608                 if ( !$first ) {
1609                         $retVal .= ' ';
1610                 } else {
1611                         $first = false;
1612                 }
1613
1614                 if ( wfIsWindows() ) {
1615                         // Escaping for an MSVC-style command line parser and CMD.EXE
1616                         // Refs:
1617                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1618                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1619                         //  * Bug #13518
1620                         //  * CR r63214
1621                         // Double the backslashes before any double quotes. Escape the double quotes.
1622                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1623                         $arg = '';
1624                         $iteration = 0;
1625                         foreach ( $tokens as $token ) {
1626                                 if ( $iteration % 2 == 1 ) {
1627                                         // Delimiter, a double quote preceded by zero or more slashes
1628                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1629                                 } elseif ( $iteration % 4 == 2 ) {
1630                                         // ^ in $token will be outside quotes, need to be escaped
1631                                         $arg .= str_replace( '^', '^^', $token );
1632                                 } else { // $iteration % 4 == 0
1633                                         // ^ in $token will appear inside double quotes, so leave as is
1634                                         $arg .= $token;
1635                                 }
1636                                 $iteration++;
1637                         }
1638                         // Double the backslashes before the end of the string, because
1639                         // we will soon add a quote
1640                         $m = array();
1641                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1642                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1643                         }
1644
1645                         // Add surrounding quotes
1646                         $retVal .= '"' . $arg . '"';
1647                 } else {
1648                         $retVal .= escapeshellarg( $arg );
1649                 }
1650         }
1651         return $retVal;
1652 }
1653
1654 /**
1655  * wfMerge attempts to merge differences between three texts.
1656  * Returns true for a clean merge and false for failure or a conflict.
1657  *
1658  * @param $old String
1659  * @param $mine String
1660  * @param $yours String
1661  * @param $result String
1662  * @return Bool
1663  */
1664 function wfMerge( $old, $mine, $yours, &$result ) {
1665         global $wgDiff3;
1666
1667         # This check may also protect against code injection in
1668         # case of broken installations.
1669         wfSuppressWarnings();
1670         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1671         wfRestoreWarnings();
1672
1673         if( !$haveDiff3 ) {
1674                 wfDebug( "diff3 not found\n" );
1675                 return false;
1676         }
1677
1678         # Make temporary files
1679         $td = wfTempDir();
1680         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1681         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1682         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1683
1684         fwrite( $oldtextFile, $old );
1685         fclose( $oldtextFile );
1686         fwrite( $mytextFile, $mine );
1687         fclose( $mytextFile );
1688         fwrite( $yourtextFile, $yours );
1689         fclose( $yourtextFile );
1690
1691         # Check for a conflict
1692         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1693                 wfEscapeShellArg( $mytextName ) . ' ' .
1694                 wfEscapeShellArg( $oldtextName ) . ' ' .
1695                 wfEscapeShellArg( $yourtextName );
1696         $handle = popen( $cmd, 'r' );
1697
1698         if( fgets( $handle, 1024 ) ) {
1699                 $conflict = true;
1700         } else {
1701                 $conflict = false;
1702         }
1703         pclose( $handle );
1704
1705         # Merge differences
1706         $cmd = $wgDiff3 . ' -a -e --merge ' .
1707                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1708         $handle = popen( $cmd, 'r' );
1709         $result = '';
1710         do {
1711                 $data = fread( $handle, 8192 );
1712                 if ( strlen( $data ) == 0 ) {
1713                         break;
1714                 }
1715                 $result .= $data;
1716         } while ( true );
1717         pclose( $handle );
1718         unlink( $mytextName );
1719         unlink( $oldtextName );
1720         unlink( $yourtextName );
1721
1722         if ( $result === '' && $old !== '' && !$conflict ) {
1723                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1724                 $conflict = true;
1725         }
1726         return !$conflict;
1727 }
1728
1729 /**
1730  * Returns unified plain-text diff of two texts.
1731  * Useful for machine processing of diffs.
1732  *
1733  * @param $before String: the text before the changes.
1734  * @param $after String: the text after the changes.
1735  * @param $params String: command-line options for the diff command.
1736  * @return String: unified diff of $before and $after
1737  */
1738 function wfDiff( $before, $after, $params = '-u' ) {
1739         if ( $before == $after ) {
1740                 return '';
1741         }
1742
1743         global $wgDiff;
1744         wfSuppressWarnings();
1745         $haveDiff = $wgDiff && file_exists( $wgDiff );
1746         wfRestoreWarnings();
1747
1748         # This check may also protect against code injection in
1749         # case of broken installations.
1750         if( !$haveDiff ) {
1751                 wfDebug( "diff executable not found\n" );
1752                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1753                 $format = new UnifiedDiffFormatter();
1754                 return $format->format( $diffs );
1755         }
1756
1757         # Make temporary files
1758         $td = wfTempDir();
1759         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1760         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1761
1762         fwrite( $oldtextFile, $before );
1763         fclose( $oldtextFile );
1764         fwrite( $newtextFile, $after );
1765         fclose( $newtextFile );
1766
1767         // Get the diff of the two files
1768         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1769
1770         $h = popen( $cmd, 'r' );
1771
1772         $diff = '';
1773
1774         do {
1775                 $data = fread( $h, 8192 );
1776                 if ( strlen( $data ) == 0 ) {
1777                         break;
1778                 }
1779                 $diff .= $data;
1780         } while ( true );
1781
1782         // Clean up
1783         pclose( $h );
1784         unlink( $oldtextName );
1785         unlink( $newtextName );
1786
1787         // Kill the --- and +++ lines. They're not useful.
1788         $diff_lines = explode( "\n", $diff );
1789         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1790                 unset( $diff_lines[0] );
1791         }
1792         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1793                 unset( $diff_lines[1] );
1794         }
1795
1796         $diff = implode( "\n", $diff_lines );
1797
1798         return $diff;
1799 }
1800
1801 /**
1802  * A wrapper around the PHP function var_export().
1803  * Either print it or add it to the regular output ($wgOut).
1804  *
1805  * @param $var A PHP variable to dump.
1806  */
1807 function wfVarDump( $var ) {
1808         global $wgOut;
1809         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1810         if ( headers_sent() || !@is_object( $wgOut ) ) {
1811                 print $s;
1812         } else {
1813                 $wgOut->addHTML( $s );
1814         }
1815 }
1816
1817 /**
1818  * Provide a simple HTTP error.
1819  *
1820  * @param $code Int|String
1821  * @param $label String
1822  * @param $desc String
1823  */
1824 function wfHttpError( $code, $label, $desc ) {
1825         global $wgOut;
1826         $wgOut->disable();
1827         header( "HTTP/1.0 $code $label" );
1828         header( "Status: $code $label" );
1829         $wgOut->sendCacheControl();
1830
1831         header( 'Content-type: text/html; charset=utf-8' );
1832         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1833                 '<html><head><title>' .
1834                 htmlspecialchars( $label ) .
1835                 '</title></head><body><h1>' .
1836                 htmlspecialchars( $label ) .
1837                 '</h1><p>' .
1838                 nl2br( htmlspecialchars( $desc ) ) .
1839                 "</p></body></html>\n";
1840 }
1841
1842 /**
1843  * Clear away any user-level output buffers, discarding contents.
1844  *
1845  * Suitable for 'starting afresh', for instance when streaming
1846  * relatively large amounts of data without buffering, or wanting to
1847  * output image files without ob_gzhandler's compression.
1848  *
1849  * The optional $resetGzipEncoding parameter controls suppression of
1850  * the Content-Encoding header sent by ob_gzhandler; by default it
1851  * is left. See comments for wfClearOutputBuffers() for why it would
1852  * be used.
1853  *
1854  * Note that some PHP configuration options may add output buffer
1855  * layers which cannot be removed; these are left in place.
1856  *
1857  * @param $resetGzipEncoding Bool
1858  */
1859 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1860         if( $resetGzipEncoding ) {
1861                 // Suppress Content-Encoding and Content-Length
1862                 // headers from 1.10+s wfOutputHandler
1863                 global $wgDisableOutputCompression;
1864                 $wgDisableOutputCompression = true;
1865         }
1866         while( $status = ob_get_status() ) {
1867                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1868                         // Probably from zlib.output_compression or other
1869                         // PHP-internal setting which can't be removed.
1870                         //
1871                         // Give up, and hope the result doesn't break
1872                         // output behavior.
1873                         break;
1874                 }
1875                 if( !ob_end_clean() ) {
1876                         // Could not remove output buffer handler; abort now
1877                         // to avoid getting in some kind of infinite loop.
1878                         break;
1879                 }
1880                 if( $resetGzipEncoding ) {
1881                         if( $status['name'] == 'ob_gzhandler' ) {
1882                                 // Reset the 'Content-Encoding' field set by this handler
1883                                 // so we can start fresh.
1884                                 if ( function_exists( 'header_remove' ) ) {
1885                                         // Available since PHP 5.3.0
1886                                         header_remove( 'Content-Encoding' );
1887                                 } else {
1888                                         // We need to provide a valid content-coding. See bug 28069
1889                                         header( 'Content-Encoding: identity' );
1890                                 }
1891                                 break;
1892                         }
1893                 }
1894         }
1895 }
1896
1897 /**
1898  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1899  *
1900  * Clear away output buffers, but keep the Content-Encoding header
1901  * produced by ob_gzhandler, if any.
1902  *
1903  * This should be used for HTTP 304 responses, where you need to
1904  * preserve the Content-Encoding header of the real result, but
1905  * also need to suppress the output of ob_gzhandler to keep to spec
1906  * and avoid breaking Firefox in rare cases where the headers and
1907  * body are broken over two packets.
1908  */
1909 function wfClearOutputBuffers() {
1910         wfResetOutputBuffers( false );
1911 }
1912
1913 /**
1914  * Converts an Accept-* header into an array mapping string values to quality
1915  * factors
1916  *
1917  * @param $accept String
1918  * @param $def String default
1919  * @return Array
1920  */
1921 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1922         # No arg means accept anything (per HTTP spec)
1923         if( !$accept ) {
1924                 return array( $def => 1.0 );
1925         }
1926
1927         $prefs = array();
1928
1929         $parts = explode( ',', $accept );
1930
1931         foreach( $parts as $part ) {
1932                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1933                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1934                 $match = array();
1935                 if( !isset( $qpart ) ) {
1936                         $prefs[$value] = 1.0;
1937                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1938                         $prefs[$value] = floatval( $match[1] );
1939                 }
1940         }
1941
1942         return $prefs;
1943 }
1944
1945 /**
1946  * Checks if a given MIME type matches any of the keys in the given
1947  * array. Basic wildcards are accepted in the array keys.
1948  *
1949  * Returns the matching MIME type (or wildcard) if a match, otherwise
1950  * NULL if no match.
1951  *
1952  * @param $type String
1953  * @param $avail Array
1954  * @return string
1955  * @private
1956  */
1957 function mimeTypeMatch( $type, $avail ) {
1958         if( array_key_exists( $type, $avail ) ) {
1959                 return $type;
1960         } else {
1961                 $parts = explode( '/', $type );
1962                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1963                         return $parts[0] . '/*';
1964                 } elseif( array_key_exists( '*/*', $avail ) ) {
1965                         return '*/*';
1966                 } else {
1967                         return null;
1968                 }
1969         }
1970 }
1971
1972 /**
1973  * Returns the 'best' match between a client's requested internet media types
1974  * and the server's list of available types. Each list should be an associative
1975  * array of type to preference (preference is a float between 0.0 and 1.0).
1976  * Wildcards in the types are acceptable.
1977  *
1978  * @param $cprefs Array: client's acceptable type list
1979  * @param $sprefs Array: server's offered types
1980  * @return string
1981  *
1982  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1983  * XXX: generalize to negotiate other stuff
1984  */
1985 function wfNegotiateType( $cprefs, $sprefs ) {
1986         $combine = array();
1987
1988         foreach( array_keys($sprefs) as $type ) {
1989                 $parts = explode( '/', $type );
1990                 if( $parts[1] != '*' ) {
1991                         $ckey = mimeTypeMatch( $type, $cprefs );
1992                         if( $ckey ) {
1993                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1994                         }
1995                 }
1996         }
1997
1998         foreach( array_keys( $cprefs ) as $type ) {
1999                 $parts = explode( '/', $type );
2000                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2001                         $skey = mimeTypeMatch( $type, $sprefs );
2002                         if( $skey ) {
2003                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2004                         }
2005                 }
2006         }
2007
2008         $bestq = 0;
2009         $besttype = null;
2010
2011         foreach( array_keys( $combine ) as $type ) {
2012                 if( $combine[$type] > $bestq ) {
2013                         $besttype = $type;
2014                         $bestq = $combine[$type];
2015                 }
2016         }
2017
2018         return $besttype;
2019 }
2020
2021 /**
2022  * Reference-counted warning suppression
2023  *
2024  * @param $end Bool
2025  */
2026 function wfSuppressWarnings( $end = false ) {
2027         static $suppressCount = 0;
2028         static $originalLevel = false;
2029
2030         if ( $end ) {
2031                 if ( $suppressCount ) {
2032                         --$suppressCount;
2033                         if ( !$suppressCount ) {
2034                                 error_reporting( $originalLevel );
2035                         }
2036                 }
2037         } else {
2038                 if ( !$suppressCount ) {
2039                         // E_DEPRECATED is undefined in PHP 5.2
2040                         if( !defined( 'E_DEPRECATED' ) ){
2041                                 define( 'E_DEPRECATED', 8192 );
2042                         }
2043                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2044                 }
2045                 ++$suppressCount;
2046         }
2047 }
2048
2049 /**
2050  * Restore error level to previous value
2051  */
2052 function wfRestoreWarnings() {
2053         wfSuppressWarnings( true );
2054 }
2055
2056 # Autodetect, convert and provide timestamps of various types
2057
2058 /**
2059  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2060  */
2061 define( 'TS_UNIX', 0 );
2062
2063 /**
2064  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2065  */
2066 define( 'TS_MW', 1 );
2067
2068 /**
2069  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2070  */
2071 define( 'TS_DB', 2 );
2072
2073 /**
2074  * RFC 2822 format, for E-mail and HTTP headers
2075  */
2076 define( 'TS_RFC2822', 3 );
2077
2078 /**
2079  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2080  *
2081  * This is used by Special:Export
2082  */
2083 define( 'TS_ISO_8601', 4 );
2084
2085 /**
2086  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2087  *
2088  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2089  *       DateTime tag and page 36 for the DateTimeOriginal and
2090  *       DateTimeDigitized tags.
2091  */
2092 define( 'TS_EXIF', 5 );
2093
2094 /**
2095  * Oracle format time.
2096  */
2097 define( 'TS_ORACLE', 6 );
2098
2099 /**
2100  * Postgres format time.
2101  */
2102 define( 'TS_POSTGRES', 7 );
2103
2104 /**
2105  * DB2 format time
2106  */
2107 define( 'TS_DB2', 8 );
2108
2109 /**
2110  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2111  */
2112 define( 'TS_ISO_8601_BASIC', 9 );
2113
2114 /**
2115  * Get a timestamp string in one of various formats
2116  *
2117  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2118  *                    function will autodetect which format is supplied and act
2119  *                    accordingly.
2120  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2121  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2122  */
2123 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2124         $uts = 0;
2125         $da = array();
2126         $strtime = '';
2127
2128         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2129                 $uts = time();
2130                 $strtime = "@$uts";
2131         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2132                 # TS_DB
2133         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2134                 # TS_EXIF
2135         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2136                 # TS_MW
2137         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2138                 # TS_UNIX
2139                 $uts = $ts;
2140                 $strtime = "@$ts"; // Undocumented?
2141         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2142                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2143                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2144                                 str_replace( '+00:00', 'UTC', $ts ) );
2145         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2146                 # TS_ISO_8601
2147         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2148                 #TS_ISO_8601_BASIC
2149         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2150                 # TS_POSTGRES
2151         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2152                 # TS_POSTGRES
2153         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2154                 # TS_DB2
2155         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2156                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2157                                                         '[ \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
2158                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2159                 # The regex is a superset of rfc2822 for readability
2160                 $strtime = strtok( $ts, ';' );
2161         } 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 ) ) {
2162                 # TS_RFC850
2163                 $strtime = $ts;
2164         } 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 ) ) {
2165                 # asctime
2166                 $strtime = $ts;
2167         } else {
2168                 # Bogus value...
2169                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2170
2171                 return false;
2172         }
2173
2174
2175
2176         static $formats = array(
2177                 TS_UNIX => 'U',
2178                 TS_MW => 'YmdHis',
2179                 TS_DB => 'Y-m-d H:i:s',
2180                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2181                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2182                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2183                 TS_RFC2822 => 'D, d M Y H:i:s',
2184                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2185                 TS_POSTGRES => 'Y-m-d H:i:s',
2186                 TS_DB2 => 'Y-m-d H:i:s',
2187         );
2188
2189         if ( !isset( $formats[$outputtype] ) ) {
2190                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2191         }
2192
2193         if ( function_exists( "date_create" ) ) {
2194                 if ( count( $da ) ) {
2195                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2196                                 (int)$da[1], (int)$da[2], (int)$da[3],
2197                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2198
2199                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2200                 } elseif ( $strtime ) {
2201                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2202                 } else {
2203                         return false;
2204                 }
2205
2206                 if ( !$d ) {
2207                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2208                         return false;
2209                 }
2210
2211                 $output = $d->format( $formats[$outputtype] );
2212         } else {
2213                 if ( count( $da ) ) {
2214                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2215                         // We may want to handle that explicitly at some point
2216                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2217                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2218                 } elseif ( $strtime ) {
2219                         $uts = strtotime( $strtime );
2220                 }
2221
2222                 if ( $uts === false ) {
2223                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2224                         return false;
2225                 }
2226
2227                 if ( TS_UNIX == $outputtype ) {
2228                         return $uts;
2229                 }
2230                 $output = gmdate( $formats[$outputtype], $uts );
2231         }
2232
2233         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2234                 $output .= ' GMT';
2235         }
2236
2237         return $output;
2238 }
2239
2240 /**
2241  * Return a formatted timestamp, or null if input is null.
2242  * For dealing with nullable timestamp columns in the database.
2243  *
2244  * @param $outputtype Integer
2245  * @param $ts String
2246  * @return String
2247  */
2248 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2249         if( is_null( $ts ) ) {
2250                 return null;
2251         } else {
2252                 return wfTimestamp( $outputtype, $ts );
2253         }
2254 }
2255
2256 /**
2257  * Convenience function; returns MediaWiki timestamp for the present time.
2258  *
2259  * @return string
2260  */
2261 function wfTimestampNow() {
2262         # return NOW
2263         return wfTimestamp( TS_MW, time() );
2264 }
2265
2266 /**
2267  * Check if the operating system is Windows
2268  *
2269  * @return Bool: true if it's Windows, False otherwise.
2270  */
2271 function wfIsWindows() {
2272         static $isWindows = null;
2273         if ( $isWindows === null ) {
2274                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2275         }
2276         return $isWindows;
2277 }
2278
2279 /**
2280  * Check if we are running under HipHop
2281  *
2282  * @return Bool
2283  */
2284 function wfIsHipHop() {
2285         return function_exists( 'hphp_thread_set_warmup_enabled' );
2286 }
2287
2288 /**
2289  * Swap two variables
2290  *
2291  * @param $x Mixed
2292  * @param $y Mixed
2293  */
2294 function swap( &$x, &$y ) {
2295         $z = $x;
2296         $x = $y;
2297         $y = $z;
2298 }
2299
2300 /**
2301  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2302  * TEMP environment variables are then checked in sequence, and if none are set
2303  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2304  * or C:\Windows\Temp for Windows and hope for the best.
2305  * It is common to call it with tempnam().
2306  *
2307  * NOTE: When possible, use instead the tmpfile() function to create
2308  * temporary files to avoid race conditions on file creation, etc.
2309  *
2310  * @return String
2311  */
2312 function wfTempDir() {
2313         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2314                 $tmp = getenv( $var );
2315                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2316                         return $tmp;
2317                 }
2318         }
2319         if( function_exists( 'sys_get_temp_dir' ) ) {
2320                 return sys_get_temp_dir();
2321         }
2322         # Usual defaults
2323         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2324 }
2325
2326 /**
2327  * Make directory, and make all parent directories if they don't exist
2328  *
2329  * @param $dir String: full path to directory to create
2330  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2331  * @param $caller String: optional caller param for debugging.
2332  * @return bool
2333  */
2334 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2335         global $wgDirectoryMode;
2336
2337         if ( !is_null( $caller ) ) {
2338                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2339         }
2340
2341         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2342                 return true;
2343         }
2344
2345         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2346
2347         if ( is_null( $mode ) ) {
2348                 $mode = $wgDirectoryMode;
2349         }
2350
2351         // Turn off the normal warning, we're doing our own below
2352         wfSuppressWarnings();
2353         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2354         wfRestoreWarnings();
2355
2356         if( !$ok ) {
2357                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2358                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2359         }
2360         return $ok;
2361 }
2362
2363 /**
2364  * Increment a statistics counter
2365  *
2366  * @param $key String
2367  * @param $count Int
2368  */
2369 function wfIncrStats( $key, $count = 1 ) {
2370         global $wgStatsMethod;
2371
2372         $count = intval( $count );
2373
2374         if( $wgStatsMethod == 'udp' ) {
2375                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2376                 static $socket;
2377
2378                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2379
2380                 if ( !$socket ) {
2381                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2382                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2383                         socket_sendto(
2384                                 $socket,
2385                                 $statline,
2386                                 strlen( $statline ),
2387                                 0,
2388                                 $wgUDPProfilerHost,
2389                                 $wgUDPProfilerPort
2390                         );
2391                 }
2392                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2393                 wfSuppressWarnings();
2394                 socket_sendto(
2395                         $socket,
2396                         $statline,
2397                         strlen( $statline ),
2398                         0,
2399                         $wgUDPProfilerHost,
2400                         $wgUDPProfilerPort
2401                 );
2402                 wfRestoreWarnings();
2403         } elseif( $wgStatsMethod == 'cache' ) {
2404                 global $wgMemc;
2405                 $key = wfMemcKey( 'stats', $key );
2406                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2407                         $wgMemc->add( $key, $count );
2408                 }
2409         } else {
2410                 // Disabled
2411         }
2412 }
2413
2414 /**
2415  * @param $nr Mixed: the number to format
2416  * @param $acc Integer: the number of digits after the decimal point, default 2
2417  * @param $round Boolean: whether or not to round the value, default true
2418  * @return float
2419  */
2420 function wfPercent( $nr, $acc = 2, $round = true ) {
2421         $ret = sprintf( "%.${acc}f", $nr );
2422         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2423 }
2424
2425 /**
2426  * Find out whether or not a mixed variable exists in a string
2427  *
2428  * @param $needle String
2429  * @param $str String
2430  * @param $insensitive Boolean
2431  * @return Boolean
2432  */
2433 function in_string( $needle, $str, $insensitive = false ) {
2434         $func = 'strpos';
2435         if( $insensitive ) $func = 'stripos';
2436
2437         return $func( $str, $needle ) !== false;
2438 }
2439
2440 function wfSpecialList( $page, $details ) {
2441         global $wgContLang;
2442         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2443         return $page . $details;
2444 }
2445
2446 /**
2447  * Returns a regular expression of url protocols
2448  *
2449  * @return String
2450  */
2451 function wfUrlProtocols() {
2452         global $wgUrlProtocols;
2453
2454         static $retval = null;
2455         if ( !is_null( $retval ) ) {
2456                 return $retval;
2457         }
2458
2459         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2460         // with LocalSettings files from 1.5
2461         if ( is_array( $wgUrlProtocols ) ) {
2462                 $protocols = array();
2463                 foreach ( $wgUrlProtocols as $protocol ) {
2464                         $protocols[] = preg_quote( $protocol, '/' );
2465                 }
2466
2467                 $retval = implode( '|', $protocols );
2468         } else {
2469                 $retval = $wgUrlProtocols;
2470         }
2471         return $retval;
2472 }
2473
2474 /**
2475  * Safety wrapper around ini_get() for boolean settings.
2476  * The values returned from ini_get() are pre-normalized for settings
2477  * set via php.ini or php_flag/php_admin_flag... but *not*
2478  * for those set via php_value/php_admin_value.
2479  *
2480  * It's fairly common for people to use php_value instead of php_flag,
2481  * which can leave you with an 'off' setting giving a false positive
2482  * for code that just takes the ini_get() return value as a boolean.
2483  *
2484  * To make things extra interesting, setting via php_value accepts
2485  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2486  * Unrecognized values go false... again opposite PHP's own coercion
2487  * from string to bool.
2488  *
2489  * Luckily, 'properly' set settings will always come back as '0' or '1',
2490  * so we only have to worry about them and the 'improper' settings.
2491  *
2492  * I frickin' hate PHP... :P
2493  *
2494  * @param $setting String
2495  * @return Bool
2496  */
2497 function wfIniGetBool( $setting ) {
2498         $val = ini_get( $setting );
2499         // 'on' and 'true' can't have whitespace around them, but '1' can.
2500         return strtolower( $val ) == 'on'
2501                 || strtolower( $val ) == 'true'
2502                 || strtolower( $val ) == 'yes'
2503                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2504 }
2505
2506 /**
2507  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2508  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2509  *
2510  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2511  *                          should be omitted
2512  * @param $fileName String Name of the library, if not $extension.suffix
2513  * @return Bool - Whether or not the extension is loaded
2514  */
2515 function wfDl( $extension, $fileName = null ) {
2516         if( extension_loaded( $extension ) ) {
2517                 return true;
2518         }
2519
2520         $canDl = false;
2521         $sapi = php_sapi_name();
2522         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2523                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2524         {
2525                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2526                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2527         }
2528
2529         if( $canDl ) {
2530                 $fileName = $fileName ? $fileName : $extension;
2531                 if( wfIsWindows() ) {
2532                         $fileName = 'php_' . $fileName;
2533                 }
2534                 wfSuppressWarnings();
2535                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2536                 wfRestoreWarnings();
2537         }
2538         return extension_loaded( $extension );
2539 }
2540
2541 /**
2542  * Execute a shell command, with time and memory limits mirrored from the PHP
2543  * configuration if supported.
2544  * @param $cmd String Command line, properly escaped for shell.
2545  * @param &$retval optional, will receive the program's exit code.
2546  *                 (non-zero is usually failure)
2547  * @param $environ Array optional environment variables which should be
2548  *                 added to the executed command environment.
2549  * @return collected stdout as a string (trailing newlines stripped)
2550  */
2551 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2552         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2553
2554         static $disabled;
2555         if ( is_null( $disabled ) ) {
2556                 $disabled = false;
2557                 if( wfIniGetBool( 'safe_mode' ) ) {
2558                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2559                         $disabled = 'safemode';
2560                 } else {
2561                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2562                         $functions = array_map( 'trim', $functions );
2563                         $functions = array_map( 'strtolower', $functions );
2564                         if ( in_array( 'passthru', $functions ) ) {
2565                                 wfDebug( "passthru is in disabled_functions\n" );
2566                                 $disabled = 'passthru';
2567                         }
2568                 }
2569         }
2570         if ( $disabled ) {
2571                 $retval = 1;
2572                 return $disabled == 'safemode' ?
2573                         'Unable to run external programs in safe mode.' :
2574                         'Unable to run external programs, passthru() is disabled.';
2575         }
2576
2577         wfInitShellLocale();
2578
2579         $envcmd = '';
2580         foreach( $environ as $k => $v ) {
2581                 if ( wfIsWindows() ) {
2582                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2583                          * appear in the environment variable, so we must use carat escaping as documented in
2584                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2585                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2586                          * are listed there but doesn't appear to need it.
2587                          */
2588                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2589                 } else {
2590                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2591                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2592                          */
2593                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2594                 }
2595         }
2596         $cmd = $envcmd . $cmd;
2597
2598         if ( wfIsWindows() ) {
2599                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2600                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2601                 {
2602                         # Hack to work around PHP's flawed invocation of cmd.exe
2603                         # http://news.php.net/php.internals/21796
2604                         # Windows 9x doesn't accept any kind of quotes
2605                         $cmd = '"' . $cmd . '"';
2606                 }
2607         } elseif ( php_uname( 's' ) == 'Linux' ) {
2608                 $time = intval( $wgMaxShellTime );
2609                 $mem = intval( $wgMaxShellMemory );
2610                 $filesize = intval( $wgMaxShellFileSize );
2611
2612                 if ( $time > 0 && $mem > 0 ) {
2613                         $script = "$IP/bin/ulimit4.sh";
2614                         if ( is_executable( $script ) ) {
2615                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2616                         }
2617                 }
2618         }
2619         wfDebug( "wfShellExec: $cmd\n" );
2620
2621         $retval = 1; // error by default?
2622         ob_start();
2623         passthru( $cmd, $retval );
2624         $output = ob_get_contents();
2625         ob_end_clean();
2626
2627         if ( $retval == 127 ) {
2628                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2629         }
2630         return $output;
2631 }
2632
2633 /**
2634  * Workaround for http://bugs.php.net/bug.php?id=45132
2635  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2636  */
2637 function wfInitShellLocale() {
2638         static $done = false;
2639         if ( $done ) {
2640                 return;
2641         }
2642         $done = true;
2643         global $wgShellLocale;
2644         if ( !wfIniGetBool( 'safe_mode' ) ) {
2645                 putenv( "LC_CTYPE=$wgShellLocale" );
2646                 setlocale( LC_CTYPE, $wgShellLocale );
2647         }
2648 }
2649
2650 /**
2651  * This function works like "use VERSION" in Perl, the program will die with a
2652  * backtrace if the current version of PHP 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, and might depend on other versions of PHP than the main code
2656  *
2657  * Note: PHP might die due to parsing errors in some cases before it ever
2658  *       manages to call this function, such is life
2659  *
2660  * @see perldoc -f use
2661  *
2662  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2663  *                 a float
2664  */
2665 function wfUsePHP( $req_ver ) {
2666         $php_ver = PHP_VERSION;
2667
2668         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2669                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2670         }
2671 }
2672
2673 /**
2674  * This function works like "use VERSION" in Perl except it checks the version
2675  * of MediaWiki, the program will die with a backtrace if the current version
2676  * of MediaWiki is less than the version provided.
2677  *
2678  * This is useful for extensions which due to their nature are not kept in sync
2679  * with releases
2680  *
2681  * @see perldoc -f use
2682  *
2683  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2684  *                 a float
2685  */
2686 function wfUseMW( $req_ver ) {
2687         global $wgVersion;
2688
2689         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2690                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2691         }
2692 }
2693
2694 /**
2695  * Return the final portion of a pathname.
2696  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2697  * http://bugs.php.net/bug.php?id=33898
2698  *
2699  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2700  * We'll consider it so always, as we don't want \s in our Unix paths either.
2701  *
2702  * @param $path String
2703  * @param $suffix String: to remove if present
2704  * @return String
2705  */
2706 function wfBaseName( $path, $suffix = '' ) {
2707         $encSuffix = ( $suffix == '' )
2708                 ? ''
2709                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2710         $matches = array();
2711         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2712                 return $matches[1];
2713         } else {
2714                 return '';
2715         }
2716 }
2717
2718 /**
2719  * Generate a relative path name to the given file.
2720  * May explode on non-matching case-insensitive paths,
2721  * funky symlinks, etc.
2722  *
2723  * @param $path String: absolute destination path including target filename
2724  * @param $from String: Absolute source path, directory only
2725  * @return String
2726  */
2727 function wfRelativePath( $path, $from ) {
2728         // Normalize mixed input on Windows...
2729         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2730         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2731
2732         // Trim trailing slashes -- fix for drive root
2733         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2734         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2735
2736         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2737         $against = explode( DIRECTORY_SEPARATOR, $from );
2738
2739         if( $pieces[0] !== $against[0] ) {
2740                 // Non-matching Windows drive letters?
2741                 // Return a full path.
2742                 return $path;
2743         }
2744
2745         // Trim off common prefix
2746         while( count( $pieces ) && count( $against )
2747                 && $pieces[0] == $against[0] ) {
2748                 array_shift( $pieces );
2749                 array_shift( $against );
2750         }
2751
2752         // relative dots to bump us to the parent
2753         while( count( $against ) ) {
2754                 array_unshift( $pieces, '..' );
2755                 array_shift( $against );
2756         }
2757
2758         array_push( $pieces, wfBaseName( $path ) );
2759
2760         return implode( DIRECTORY_SEPARATOR, $pieces );
2761 }
2762
2763 /**
2764  * parse_url() work-alike, but non-broken.  Differences:
2765  *
2766  * 1) Does not raise warnings on bad URLs (just returns false)
2767  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2768  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2769  *
2770  * @param $url String: a URL to parse
2771  * @return Array: bits of the URL in an associative array, per PHP docs
2772  */
2773 function wfParseUrl( $url ) {
2774         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2775         wfSuppressWarnings();
2776         $bits = parse_url( $url );
2777         wfRestoreWarnings();
2778         if ( !$bits ) {
2779                 return false;
2780         }
2781
2782         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2783         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2784                 $bits['delimiter'] = '://';
2785         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2786                 $bits['delimiter'] = ':';
2787                 // parse_url detects for news: and mailto: the host part of an url as path
2788                 // We have to correct this wrong detection
2789                 if ( isset( $bits['path'] ) ) {
2790                         $bits['host'] = $bits['path'];
2791                         $bits['path'] = '';
2792                 }
2793         } else {
2794                 return false;
2795         }
2796
2797         return $bits;
2798 }
2799
2800 /**
2801  * Make a URL index, appropriate for the el_index field of externallinks.
2802  *
2803  * @param $url String
2804  * @return String
2805  */
2806 function wfMakeUrlIndex( $url ) {
2807         $bits = wfParseUrl( $url );
2808
2809         // Reverse the labels in the hostname, convert to lower case
2810         // For emails reverse domainpart only
2811         if ( $bits['scheme'] == 'mailto' ) {
2812                 $mailparts = explode( '@', $bits['host'], 2 );
2813                 if ( count( $mailparts ) === 2 ) {
2814                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2815                 } else {
2816                         // No domain specified, don't mangle it
2817                         $domainpart = '';
2818                 }
2819                 $reversedHost = $domainpart . '@' . $mailparts[0];
2820         } else if ( isset( $bits['host'] ) ) {
2821                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2822         } else {
2823                 // In file: URIs for instance it's common to have an empty host,
2824                 // which turns up as not getting a 'host' member from parse_url.
2825                 $reversedHost = '.';
2826         }
2827         // Add an extra dot to the end
2828         // Why? Is it in wrong place in mailto links?
2829         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2830                 $reversedHost .= '.';
2831         }
2832         // Reconstruct the pseudo-URL
2833         $prot = $bits['scheme'];
2834         $index = $prot . $bits['delimiter'] . $reversedHost;
2835         // Leave out user and password. Add the port, path, query and fragment
2836         if ( isset( $bits['port'] ) ) {
2837                 $index .= ':' . $bits['port'];
2838         }
2839         if ( isset( $bits['path'] ) ) {
2840                 // parse_url() removes the initial '/' from the path
2841                 // for file: URLs with Windows-style paths, such as
2842                 // file:///c:/windows/stuff. We need to add it back
2843                 // to keep our division between host and path properly.
2844                 if ( strlen( $bits['path'] ) > 0 && substr( $bits['path'], 0, 1 ) !== '/' ) {
2845                         $index .= '/';
2846                 }
2847                 $index .= $bits['path'];
2848         } else {
2849                 $index .= '/';
2850         }
2851         if ( isset( $bits['query'] ) ) {
2852                 $index .= '?' . $bits['query'];
2853         }
2854         if ( isset( $bits['fragment'] ) ) {
2855                 $index .= '#' . $bits['fragment'];
2856         }
2857         return $index;
2858 }
2859
2860 /**
2861  * Do any deferred updates and clear the list
2862  *
2863  * @param $commit String: set to 'commit' to commit after every update to
2864  *                prevent lock contention
2865  */
2866 function wfDoUpdates( $commit = '' ) {
2867         global $wgDeferredUpdateList;
2868
2869         wfProfileIn( __METHOD__ );
2870
2871         // No need to get master connections in case of empty updates array
2872         if ( !count( $wgDeferredUpdateList ) ) {
2873                 wfProfileOut( __METHOD__ );
2874                 return;
2875         }
2876
2877         $doCommit = $commit == 'commit';
2878         if ( $doCommit ) {
2879                 $dbw = wfGetDB( DB_MASTER );
2880         }
2881
2882         foreach ( $wgDeferredUpdateList as $update ) {
2883                 $update->doUpdate();
2884
2885                 if ( $doCommit && $dbw->trxLevel() ) {
2886                         $dbw->commit();
2887                 }
2888         }
2889
2890         $wgDeferredUpdateList = array();
2891         wfProfileOut( __METHOD__ );
2892 }
2893
2894 /**
2895  * Convert an arbitrarily-long digit string from one numeric base
2896  * to another, optionally zero-padding to a minimum column width.
2897  *
2898  * Supports base 2 through 36; digit values 10-36 are represented
2899  * as lowercase letters a-z. Input is case-insensitive.
2900  *
2901  * @param $input String: of digits
2902  * @param $sourceBase Integer: 2-36
2903  * @param $destBase Integer: 2-36
2904  * @param $pad Integer: 1 or greater
2905  * @param $lowercase Boolean
2906  * @return String or false on invalid input
2907  */
2908 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2909         $input = strval( $input );
2910         if( $sourceBase < 2 ||
2911                 $sourceBase > 36 ||
2912                 $destBase < 2 ||
2913                 $destBase > 36 ||
2914                 $pad < 1 ||
2915                 $sourceBase != intval( $sourceBase ) ||
2916                 $destBase != intval( $destBase ) ||
2917                 $pad != intval( $pad ) ||
2918                 !is_string( $input ) ||
2919                 $input == '' ) {
2920                 return false;
2921         }
2922         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2923         $inDigits = array();
2924         $outChars = '';
2925
2926         // Decode and validate input string
2927         $input = strtolower( $input );
2928         for( $i = 0; $i < strlen( $input ); $i++ ) {
2929                 $n = strpos( $digitChars, $input[$i] );
2930                 if( $n === false || $n > $sourceBase ) {
2931                         return false;
2932                 }
2933                 $inDigits[] = $n;
2934         }
2935
2936         // Iterate over the input, modulo-ing out an output digit
2937         // at a time until input is gone.
2938         while( count( $inDigits ) ) {
2939                 $work = 0;
2940                 $workDigits = array();
2941
2942                 // Long division...
2943                 foreach( $inDigits as $digit ) {
2944                         $work *= $sourceBase;
2945                         $work += $digit;
2946
2947                         if( $work < $destBase ) {
2948                                 // Gonna need to pull another digit.
2949                                 if( count( $workDigits ) ) {
2950                                         // Avoid zero-padding; this lets us find
2951                                         // the end of the input very easily when
2952                                         // length drops to zero.
2953                                         $workDigits[] = 0;
2954                                 }
2955                         } else {
2956                                 // Finally! Actual division!
2957                                 $workDigits[] = intval( $work / $destBase );
2958
2959                                 // Isn't it annoying that most programming languages
2960                                 // don't have a single divide-and-remainder operator,
2961                                 // even though the CPU implements it that way?
2962                                 $work = $work % $destBase;
2963                         }
2964                 }
2965
2966                 // All that division leaves us with a remainder,
2967                 // which is conveniently our next output digit.
2968                 $outChars .= $digitChars[$work];
2969
2970                 // And we continue!
2971                 $inDigits = $workDigits;
2972         }
2973
2974         while( strlen( $outChars ) < $pad ) {
2975                 $outChars .= '0';
2976         }
2977
2978         return strrev( $outChars );
2979 }
2980
2981 /**
2982  * Create an object with a given name and an array of construct parameters
2983  *
2984  * @param $name String
2985  * @param $p Array: parameters
2986  * @deprecated since 1.18, warnings in 1.19, removal in 1.20
2987  */
2988 function wfCreateObject( $name, $p ) {
2989         wfDeprecated( __FUNCTION__ );
2990         return MWFunction::newObj( $name, $p );
2991 }
2992
2993 function wfHttpOnlySafe() {
2994         global $wgHttpOnlyBlacklist;
2995
2996         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2997                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2998                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2999                                 return false;
3000                         }
3001                 }
3002         }
3003
3004         return true;
3005 }
3006
3007 /**
3008  * Initialise php session
3009  *
3010  * @param $sessionId Bool
3011  */
3012 function wfSetupSession( $sessionId = false ) {
3013         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3014                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3015         if( $wgSessionsInMemcached ) {
3016                 if ( !defined( 'MW_COMPILED' ) ) {
3017                         global $IP;
3018                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3019                 }
3020                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3021                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3022
3023                 // It's necessary to register a shutdown function to call session_write_close(),
3024                 // because by the time the request shutdown function for the session module is
3025                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3026                 // this way are called before object destruction.
3027                 register_shutdown_function( 'memsess_write_close' );
3028         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3029                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3030                 # hasn't already been set to the desired value (that causes errors)
3031                 ini_set( 'session.save_handler', $wgSessionHandler );
3032         }
3033         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3034         wfDebugLog( 'cookie',
3035                 'session_set_cookie_params: "' . implode( '", "',
3036                         array(
3037                                 0,
3038                                 $wgCookiePath,
3039                                 $wgCookieDomain,
3040                                 $wgCookieSecure,
3041                                 $httpOnlySafe ) ) . '"' );
3042         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3043         session_cache_limiter( 'private, must-revalidate' );
3044         if ( $sessionId ) {
3045                 session_id( $sessionId );
3046         }
3047         wfSuppressWarnings();
3048         session_start();
3049         wfRestoreWarnings();
3050 }
3051
3052 /**
3053  * Get an object from the precompiled serialized directory
3054  *
3055  * @param $name String
3056  * @return Mixed: the variable on success, false on failure
3057  */
3058 function wfGetPrecompiledData( $name ) {
3059         global $IP;
3060
3061         $file = "$IP/serialized/$name";
3062         if ( file_exists( $file ) ) {
3063                 $blob = file_get_contents( $file );
3064                 if ( $blob ) {
3065                         return unserialize( $blob );
3066                 }
3067         }
3068         return false;
3069 }
3070
3071 /**
3072  * Get a cache key
3073  *
3074  * @param varargs
3075  * @return String
3076  */
3077 function wfMemcKey( /*... */ ) {
3078         $args = func_get_args();
3079         $key = wfWikiID() . ':' . implode( ':', $args );
3080         $key = str_replace( ' ', '_', $key );
3081         return $key;
3082 }
3083
3084 /**
3085  * Get a cache key for a foreign DB
3086  *
3087  * @param $db String
3088  * @param $prefix String
3089  * @param varargs String
3090  * @return String
3091  */
3092 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3093         $args = array_slice( func_get_args(), 2 );
3094         if ( $prefix ) {
3095                 $key = "$db-$prefix:" . implode( ':', $args );
3096         } else {
3097                 $key = $db . ':' . implode( ':', $args );
3098         }
3099         return $key;
3100 }
3101
3102 /**
3103  * Get an ASCII string identifying this wiki
3104  * This is used as a prefix in memcached keys
3105  *
3106  * @return String
3107  */
3108 function wfWikiID() {
3109         global $wgDBprefix, $wgDBname;
3110         if ( $wgDBprefix ) {
3111                 return "$wgDBname-$wgDBprefix";
3112         } else {
3113                 return $wgDBname;
3114         }
3115 }
3116
3117 /**
3118  * Split a wiki ID into DB name and table prefix
3119  *
3120  * @param $wiki String
3121  * @param $bits String
3122  */
3123 function wfSplitWikiID( $wiki ) {
3124         $bits = explode( '-', $wiki, 2 );
3125         if ( count( $bits ) < 2 ) {
3126                 $bits[] = '';
3127         }
3128         return $bits;
3129 }
3130
3131 /**
3132  * Get a Database object.
3133  *
3134  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3135  *            master (for write queries), DB_SLAVE for potentially lagged read
3136  *            queries, or an integer >= 0 for a particular server.
3137  *
3138  * @param $groups Mixed: query groups. An array of group names that this query
3139  *                belongs to. May contain a single string if the query is only
3140  *                in one group.
3141  *
3142  * @param $wiki String: the wiki ID, or false for the current wiki
3143  *
3144  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3145  * will always return the same object, unless the underlying connection or load
3146  * balancer is manually destroyed.
3147  *
3148  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3149  * updater to ensure that a proper database is being updated.
3150  *
3151  * @return DatabaseBase
3152  */
3153 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3154         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3155 }
3156
3157 /**
3158  * Get a load balancer object.
3159  *
3160  * @param $wiki String: wiki ID, or false for the current wiki
3161  * @return LoadBalancer
3162  */
3163 function wfGetLB( $wiki = false ) {
3164         return wfGetLBFactory()->getMainLB( $wiki );
3165 }
3166
3167 /**
3168  * Get the load balancer factory object
3169  *
3170  * @return LBFactory
3171  */
3172 function &wfGetLBFactory() {
3173         return LBFactory::singleton();
3174 }
3175
3176 /**
3177  * Find a file.
3178  * Shortcut for RepoGroup::singleton()->findFile()
3179  *
3180  * @param $title String or Title object
3181  * @param $options Associative array of options:
3182  *     time:           requested time for an archived image, or false for the
3183  *                     current version. An image object will be returned which was
3184  *                     created at the specified time.
3185  *
3186  *     ignoreRedirect: If true, do not follow file redirects
3187  *
3188  *     private:        If true, return restricted (deleted) files if the current
3189  *                     user is allowed to view them. Otherwise, such files will not
3190  *                     be found.
3191  *
3192  *     bypassCache:    If true, do not use the process-local cache of File objects
3193  *
3194  * @return File, or false if the file does not exist
3195  */
3196 function wfFindFile( $title, $options = array() ) {
3197         return RepoGroup::singleton()->findFile( $title, $options );
3198 }
3199
3200 /**
3201  * Get an object referring to a locally registered file.
3202  * Returns a valid placeholder object if the file does not exist.
3203  *
3204  * @param $title Title or String
3205  * @return File, or null if passed an invalid Title
3206  */
3207 function wfLocalFile( $title ) {
3208         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3209 }
3210
3211 /**
3212  * Should low-performance queries be disabled?
3213  *
3214  * @return Boolean
3215  * @codeCoverageIgnore
3216  */
3217 function wfQueriesMustScale() {
3218         global $wgMiserMode;
3219         return $wgMiserMode
3220                 || ( SiteStats::pages() > 100000
3221                 && SiteStats::edits() > 1000000
3222                 && SiteStats::users() > 10000 );
3223 }
3224
3225 /**
3226  * Get the path to a specified script file, respecting file
3227  * extensions; this is a wrapper around $wgScriptExtension etc.
3228  *
3229  * @param $script String: script filename, sans extension
3230  * @return String
3231  */
3232 function wfScript( $script = 'index' ) {
3233         global $wgScriptPath, $wgScriptExtension;
3234         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3235 }
3236
3237 /**
3238  * Get the script URL.
3239  *
3240  * @return script URL
3241  */
3242 function wfGetScriptUrl() {
3243         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3244                 #
3245                 # as it was called, minus the query string.
3246                 #
3247                 # Some sites use Apache rewrite rules to handle subdomains,
3248                 # and have PHP set up in a weird way that causes PHP_SELF
3249                 # to contain the rewritten URL instead of the one that the
3250                 # outside world sees.
3251                 #
3252                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3253                 # provides containing the "before" URL.
3254                 return $_SERVER['SCRIPT_NAME'];
3255         } else {
3256                 return $_SERVER['URL'];
3257         }
3258 }
3259
3260 /**
3261  * Convenience function converts boolean values into "true"
3262  * or "false" (string) values
3263  *
3264  * @param $value Boolean
3265  * @return String
3266  */
3267 function wfBoolToStr( $value ) {
3268         return $value ? 'true' : 'false';
3269 }
3270
3271 /**
3272  * Load an extension messages file
3273  *
3274  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3275  * @codeCoverageIgnore
3276  */
3277 function wfLoadExtensionMessages() {
3278         wfDeprecated( __FUNCTION__ );
3279 }
3280
3281 /**
3282  * Get a platform-independent path to the null file, e.g. /dev/null
3283  *
3284  * @return string
3285  */
3286 function wfGetNull() {
3287         return wfIsWindows()
3288                 ? 'NUL'
3289                 : '/dev/null';
3290 }
3291
3292 /**
3293  * Throws a warning that $function is deprecated
3294  *
3295  * @param $function String
3296  * @return null
3297  */
3298 function wfDeprecated( $function ) {
3299         static $functionsWarned = array();
3300         if ( !isset( $functionsWarned[$function] ) ) {
3301                 $functionsWarned[$function] = true;
3302                 wfWarn( "Use of $function is deprecated.", 2 );
3303         }
3304 }
3305
3306 /**
3307  * Send a warning either to the debug log or in a PHP error depending on
3308  * $wgDevelopmentWarnings
3309  *
3310  * @param $msg String: message to send
3311  * @param $callerOffset Integer: number of items to go back in the backtrace to
3312  *        find the correct caller (1 = function calling wfWarn, ...)
3313  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3314  *        is true
3315  */
3316 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3317         global $wgDevelopmentWarnings;
3318
3319         $callers = wfDebugBacktrace();
3320         if ( isset( $callers[$callerOffset + 1] ) ) {
3321                 $callerfunc = $callers[$callerOffset + 1];
3322                 $callerfile = $callers[$callerOffset];
3323                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3324                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3325                 } else {
3326                         $file = '(internal function)';
3327                 }
3328                 $func = '';
3329                 if ( isset( $callerfunc['class'] ) ) {
3330                         $func .= $callerfunc['class'] . '::';
3331                 }
3332                 if ( isset( $callerfunc['function'] ) ) {
3333                         $func .= $callerfunc['function'];
3334                 }
3335                 $msg .= " [Called from $func in $file]";
3336         }
3337
3338         if ( $wgDevelopmentWarnings ) {
3339                 trigger_error( $msg, $level );
3340         } else {
3341                 wfDebug( "$msg\n" );
3342         }
3343 }
3344
3345 /**
3346  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3347  * and waiting for it to go down, this waits for the slaves to catch up to the
3348  * master position. Use this when updating very large numbers of rows, as
3349  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3350  * a no-op if there are no slaves.
3351  *
3352  * @param $maxLag Integer (deprecated)
3353  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3354  * @return null
3355  */
3356 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3357         $lb = wfGetLB( $wiki );
3358         // bug 27975 - Don't try to wait for slaves if there are none
3359         // Prevents permission error when getting master position
3360         if ( $lb->getServerCount() > 1 ) {
3361                 $dbw = $lb->getConnection( DB_MASTER );
3362                 $pos = $dbw->getMasterPos();
3363                 $lb->waitForAll( $pos );
3364         }
3365 }
3366
3367 /**
3368  * Used to be used for outputting text in the installer/updater
3369  * @deprecated since 1.18, warnings in 1.19, remove in 1.20
3370  */
3371 function wfOut( $s ) {
3372         wfDeprecated( __METHOD__ );
3373         global $wgCommandLineMode;
3374         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3375                 echo $s;
3376         } else {
3377                 echo htmlspecialchars( $s );
3378         }
3379         flush();
3380 }
3381
3382 /**
3383  * Count down from $n to zero on the terminal, with a one-second pause
3384  * between showing each number. For use in command-line scripts.
3385  * @codeCoverageIgnore
3386  */
3387 function wfCountDown( $n ) {
3388         for ( $i = $n; $i >= 0; $i-- ) {
3389                 if ( $i != $n ) {
3390                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3391                 }
3392                 echo $i;
3393                 flush();
3394                 if ( $i ) {
3395                         sleep( 1 );
3396                 }
3397         }
3398         echo "\n";
3399 }
3400
3401 /**
3402  * Generate a random 32-character hexadecimal token.
3403  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3404  *              characters before hashing.
3405  * @return string
3406  * @codeCoverageIgnore
3407  */
3408 function wfGenerateToken( $salt = '' ) {
3409         $salt = serialize( $salt );
3410         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3411 }
3412
3413 /**
3414  * Replace all invalid characters with -
3415  *
3416  * @param $name Mixed: filename to process
3417  * @return String
3418  */
3419 function wfStripIllegalFilenameChars( $name ) {
3420         global $wgIllegalFileChars;
3421         $name = wfBaseName( $name );
3422         $name = preg_replace(
3423                 "/[^" . Title::legalChars() . "]" .
3424                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3425                         "/",
3426                 '-',
3427                 $name
3428         );
3429         return $name;
3430 }
3431
3432 /**
3433  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3434  *
3435  * @return Integer value memory was set to.
3436  */
3437 function wfMemoryLimit() {
3438         global $wgMemoryLimit;
3439         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3440         if( $memlimit != -1 ) {
3441                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3442                 if( $conflimit == -1 ) {
3443                         wfDebug( "Removing PHP's memory limit\n" );
3444                         wfSuppressWarnings();
3445                         ini_set( 'memory_limit', $conflimit );
3446                         wfRestoreWarnings();
3447                         return $conflimit;
3448                 } elseif ( $conflimit > $memlimit ) {
3449                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3450                         wfSuppressWarnings();
3451                         ini_set( 'memory_limit', $conflimit );
3452                         wfRestoreWarnings();
3453                         return $conflimit;
3454                 }
3455         }
3456         return $memlimit;
3457 }
3458
3459 /**
3460  * Converts shorthand byte notation to integer form
3461  *
3462  * @param $string String
3463  * @return Integer
3464  */
3465 function wfShorthandToInteger( $string = '' ) {
3466         $string = trim( $string );
3467         if( $string === '' ) {
3468                 return -1;
3469         }
3470         $last = $string[strlen( $string ) - 1];
3471         $val = intval( $string );
3472         switch( $last ) {
3473                 case 'g':
3474                 case 'G':
3475                         $val *= 1024;
3476                         // break intentionally missing
3477                 case 'm':
3478                 case 'M':
3479                         $val *= 1024;
3480                         // break intentionally missing
3481                 case 'k':
3482                 case 'K':
3483                         $val *= 1024;
3484         }
3485
3486         return $val;
3487 }
3488
3489 /**
3490  * Get the normalised IETF language tag
3491  * See unit test for examples.
3492  *
3493  * @param $code String: The language code.
3494  * @return $langCode String: The language code which complying with BCP 47 standards.
3495  */
3496 function wfBCP47( $code ) {
3497         $codeSegment = explode( '-', $code );
3498         $codeBCP = array();
3499         foreach ( $codeSegment as $segNo => $seg ) {
3500                 if ( count( $codeSegment ) > 0 ) {
3501                         // when previous segment is x, it is a private segment and should be lc
3502                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3503                                 $codeBCP[$segNo] = strtolower( $seg );
3504                         // ISO 3166 country code
3505                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3506                                 $codeBCP[$segNo] = strtoupper( $seg );
3507                         // ISO 15924 script code
3508                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3509                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3510                         // Use lowercase for other cases
3511                         } else {
3512                                 $codeBCP[$segNo] = strtolower( $seg );
3513                         }
3514                 } else {
3515                 // Use lowercase for single segment
3516                         $codeBCP[$segNo] = strtolower( $seg );
3517                 }
3518         }
3519         $langCode = implode( '-', $codeBCP );
3520         return $langCode;
3521 }
3522
3523 /**
3524  * Get a cache object.
3525  *
3526  * @param integer $inputType Cache type, one the the CACHE_* constants.
3527  * @return BagOStuff
3528  */
3529 function wfGetCache( $inputType ) {
3530         return ObjectCache::getInstance( $inputType );
3531 }
3532
3533 /**
3534  * Get the main cache object
3535  *
3536  * @return BagOStuff
3537  */
3538 function wfGetMainCache() {
3539         global $wgMainCacheType;
3540         return ObjectCache::getInstance( $wgMainCacheType );
3541 }
3542
3543 /**
3544  * Get the cache object used by the message cache
3545  *
3546  * @return BagOStuff
3547  */
3548 function wfGetMessageCacheStorage() {
3549         global $wgMessageCacheType;
3550         return ObjectCache::getInstance( $wgMessageCacheType );
3551 }
3552
3553 /**
3554  * Get the cache object used by the parser cache
3555  *
3556  * @return BagOStuff
3557  */
3558 function wfGetParserCacheStorage() {
3559         global $wgParserCacheType;
3560         return ObjectCache::getInstance( $wgParserCacheType );
3561 }
3562
3563 /**
3564  * Call hook functions defined in $wgHooks
3565  *
3566  * @param $event String: event name
3567  * @param $args Array: parameters passed to hook functions
3568  * @return Boolean
3569  */
3570 function wfRunHooks( $event, $args = array() ) {
3571         return Hooks::run( $event, $args );
3572 }