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, 'action=raw' 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         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 367         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 368                 || (
 369                         isset( $_SERVER['SCRIPT_NAME'] )
 370                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 371                 ) )
 372         {
 373                 $cache = true;
 374         } else {
 375                 $cache = false;
 376         }
 377         return $cache;
 378 }
 379
 380 /**
 381  * Get microsecond timestamps for debug logs
 382  *
 383  * @return string
 384  */
 385 function wfDebugTimer() {
 386         global $wgDebugTimestamps;
 387         if ( !$wgDebugTimestamps ) {
 388                 return '';
 389         }
 390         static $start = null;
 391
 392         if ( $start === null ) {
 393                 $start = microtime( true );
 394                 $prefix = "\n$start";
 395         } else {
 396                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 397         }
 398
 399         return $prefix . '  ';
 400 }
 401
 402 /**
 403  * Send a line giving PHP memory usage.
 404  *
 405  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 406  */
 407 function wfDebugMem( $exact = false ) {
 408         $mem = memory_get_usage();
 409         if( !$exact ) {
 410                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 411         } else {
 412                 $mem .= ' bytes';
 413         }
 414         wfDebug( "Memory usage: $mem\n" );
 415 }
 416
 417 /**
 418  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 419  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 420  *
 421  * @param $logGroup String
 422  * @param $text String
 423  * @param $public Bool: whether to log the event in the public log if no private
 424  *                     log file is specified, (default true)
 425  */
 426 function wfDebugLog( $logGroup, $text, $public = true ) {
 427         global $wgDebugLogGroups, $wgShowHostnames;
 428         $text = trim( $text ) . "\n";
 429         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 430                 $time = wfTimestamp( TS_DB );
 431                 $wiki = wfWikiID();
 432                 if ( $wgShowHostnames ) {
 433                         $host = wfHostname();
 434                 } else {
 435                         $host = '';
 436                 }
 437                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 438                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 439                 }
 440         } elseif ( $public === true ) {
 441                 wfDebug( $text, true );
 442         }
 443 }
 444
 445 /**
 446  * Log for database errors
 447  *
 448  * @param $text String: database error message.
 449  */
 450 function wfLogDBError( $text ) {
 451         global $wgDBerrorLog, $wgDBname;
 452         if ( $wgDBerrorLog ) {
 453                 $host = trim(`hostname`);
 454                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 455                 wfErrorLog( $text, $wgDBerrorLog );
 456         }
 457 }
 458
 459 /**
 460  * Log to a file without getting "file size exceeded" signals.
 461  *
 462  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 463  * send lines to the specified port, prefixed by the specified prefix and a space.
 464  *
 465  * @param $text String
 466  * @param $file String filename
 467  */
 468 function wfErrorLog( $text, $file ) {
 469         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 470                 # Needs the sockets extension
 471                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 472                         // IPv6 bracketed host
 473                         $host = $m[2];
 474                         $port = intval( $m[3] );
 475                         $prefix = isset( $m[4] ) ? $m[4] : false;
 476                         $domain = AF_INET6;
 477                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 478                         $host = $m[2];
 479                         if ( !IP::isIPv4( $host ) ) {
 480                                 $host = gethostbyname( $host );
 481                         }
 482                         $port = intval( $m[3] );
 483                         $prefix = isset( $m[4] ) ? $m[4] : false;
 484                         $domain = AF_INET;
 485                 } else {
 486                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 487                 }
 488
 489                 // Clean it up for the multiplexer
 490                 if ( strval( $prefix ) !== '' ) {
 491                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 492
 493                         // Limit to 64KB
 494                         if ( strlen( $text ) > 65534 ) {
 495                                 $text = substr( $text, 0, 65534 );
 496                         }
 497
 498                         if ( substr( $text, -1 ) != "\n" ) {
 499                                 $text .= "\n";
 500                         }
 501                 } elseif ( strlen( $text ) > 65535 ) {
 502                         $text = substr( $text, 0, 65535 );
 503                 }
 504
 505                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 506                 if ( !$sock ) {
 507                         return;
 508                 }
 509                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 510                 socket_close( $sock );
 511         } else {
 512                 wfSuppressWarnings();
 513                 $exists = file_exists( $file );
 514                 $size = $exists ? filesize( $file ) : false;
 515                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 516                         file_put_contents( $file, $text, FILE_APPEND );
 517                 }
 518                 wfRestoreWarnings();
 519         }
 520 }
 521
 522 /**
 523  * @todo document
 524  */
 525 function wfLogProfilingData() {
 526         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 527         global $wgProfileLimit, $wgUser;
 528
 529         $profiler = Profiler::instance();
 530
 531         # Profiling must actually be enabled...
 532         if ( $profiler->isStub() ) {
 533                 return;
 534         }
 535
 536         // Get total page request time and only show pages that longer than
 537         // $wgProfileLimit time (default is 0)
 538         $now = wfTime();
 539         $elapsed = $now - $wgRequestTime;
 540         if ( $elapsed <= $wgProfileLimit ) {
 541                 return;
 542         }
 543
 544         $profiler->logData();
 545
 546         // Check whether this should be logged in the debug file.
 547         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 548                 return;
 549         }
 550
 551         $forward = '';
 552         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 553                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 554         }
 555         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 556                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 557         }
 558         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 559                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 560         }
 561         if ( $forward ) {
 562                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 563         }
 564         // Don't load $wgUser at this late stage just for statistics purposes
 565         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 566         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 567                 $forward .= ' anon';
 568         }
 569         $log = sprintf( "%s\t%04.3f\t%s\n",
 570                 gmdate( 'YmdHis' ), $elapsed,
 571                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 572
 573         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 574 }
 575
 576 /**
 577  * Check if the wiki read-only lock file is present. This can be used to lock
 578  * off editing functions, but doesn't guarantee that the database will not be
 579  * modified.
 580  *
 581  * @return bool
 582  */
 583 function wfReadOnly() {
 584         global $wgReadOnlyFile, $wgReadOnly;
 585
 586         if ( !is_null( $wgReadOnly ) ) {
 587                 return (bool)$wgReadOnly;
 588         }
 589         if ( $wgReadOnlyFile == '' ) {
 590                 return false;
 591         }
 592         // Set $wgReadOnly for faster access next time
 593         if ( is_file( $wgReadOnlyFile ) ) {
 594                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 595         } else {
 596                 $wgReadOnly = false;
 597         }
 598         return (bool)$wgReadOnly;
 599 }
 600
 601 function wfReadOnlyReason() {
 602         global $wgReadOnly;
 603         wfReadOnly();
 604         return $wgReadOnly;
 605 }
 606
 607 /**
 608  * Return a Language object from $langcode
 609  *
 610  * @param $langcode Mixed: either:
 611  *                  - a Language object
 612  *                  - code of the language to get the message for, if it is
 613  *                    a valid code create a language for that language, if
 614  *                    it is a string but not a valid code then make a basic
 615  *                    language object
 616  *                  - a boolean: if it's false then use the current users
 617  *                    language (as a fallback for the old parameter
 618  *                    functionality), or if it is true then use the wikis
 619  * @return Language object
 620  */
 621 function wfGetLangObj( $langcode = false ) {
 622         # Identify which language to get or create a language object for.
 623         # Using is_object here due to Stub objects.
 624         if( is_object( $langcode ) ) {
 625                 # Great, we already have the object (hopefully)!
 626                 return $langcode;
 627         }
 628
 629         global $wgContLang, $wgLanguageCode;
 630         if( $langcode === true || $langcode === $wgLanguageCode ) {
 631                 # $langcode is the language code of the wikis content language object.
 632                 # or it is a boolean and value is true
 633                 return $wgContLang;
 634         }
 635
 636         global $wgLang;
 637         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 638                 # $langcode is the language code of user language object.
 639                 # or it was a boolean and value is false
 640                 return $wgLang;
 641         }
 642
 643         $validCodes = array_keys( Language::getLanguageNames() );
 644         if( in_array( $langcode, $validCodes ) ) {
 645                 # $langcode corresponds to a valid language.
 646                 return Language::factory( $langcode );
 647         }
 648
 649         # $langcode is a string, but not a valid language code; use content language.
 650         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 651         return $wgContLang;
 652 }
 653
 654 /**
 655  * Use this instead of $wgContLang, when working with user interface.
 656  * User interface is currently hard coded according to wiki content language
 657  * in many ways, especially regarding to text direction. There is lots stuff
 658  * to fix, hence this function to keep the old behaviour unless the global
 659  * $wgBetterDirectionality is enabled (or removed when everything works).
 660  *
 661  * @return Language
 662  */
 663 function wfUILang() {
 664         global $wgBetterDirectionality;
 665         return wfGetLangObj( !$wgBetterDirectionality );
 666 }
 667
 668 /**
 669  * This is the new function for getting translated interface messages.
 670  * See the Message class for documentation how to use them.
 671  * The intention is that this function replaces all old wfMsg* functions.
 672  * @param $key \string Message key.
 673  * Varargs: normal message parameters.
 674  * @return Message
 675  * @since 1.17
 676  */
 677 function wfMessage( $key /*...*/) {
 678         $params = func_get_args();
 679         array_shift( $params );
 680         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 681                 $params = $params[0];
 682         }
 683         return new Message( $key, $params );
 684 }
 685
 686 /**
 687  * This function accepts multiple message keys and returns a message instance
 688  * for the first message which is non-empty. If all messages are empty then an
 689  * instance of the first message key is returned.
 690  * @param varargs: message keys
 691  * @return Message
 692  * @since 1.18
 693  */
 694 function wfMessageFallback( /*...*/ ) {
 695         $args = func_get_args();
 696         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
 697 }
 698
 699 /**
 700  * Get a message from anywhere, for the current user language.
 701  *
 702  * Use wfMsgForContent() instead if the message should NOT
 703  * change depending on the user preferences.
 704  *
 705  * @param $key String: lookup key for the message, usually
 706  *    defined in languages/Language.php
 707  *
 708  * This function also takes extra optional parameters (not
 709  * shown in the function definition), which can be used to
 710  * insert variable text into the predefined message.
 711  * @return String
 712  */
 713 function wfMsg( $key ) {
 714         $args = func_get_args();
 715         array_shift( $args );
 716         return wfMsgReal( $key, $args, true );
 717 }
 718
 719 /**
 720  * Same as above except doesn't transform the message
 721  *
 722  * @param $key String
 723  * @return String
 724  */
 725 function wfMsgNoTrans( $key ) {
 726         $args = func_get_args();
 727         array_shift( $args );
 728         return wfMsgReal( $key, $args, true, false, false );
 729 }
 730
 731 /**
 732  * Get a message from anywhere, for the current global language
 733  * set with $wgLanguageCode.
 734  *
 735  * Use this if the message should NOT change dependent on the
 736  * language set in the user's preferences. This is the case for
 737  * most text written into logs, as well as link targets (such as
 738  * the name of the copyright policy page). Link titles, on the
 739  * other hand, should be shown in the UI language.
 740  *
 741  * Note that MediaWiki allows users to change the user interface
 742  * language in their preferences, but a single installation
 743  * typically only contains content in one language.
 744  *
 745  * Be wary of this distinction: If you use wfMsg() where you should
 746  * use wfMsgForContent(), a user of the software may have to
 747  * customize potentially hundreds of messages in
 748  * order to, e.g., fix a link in every possible language.
 749  *
 750  * @param $key String: lookup key for the message, usually
 751  *     defined in languages/Language.php
 752  * @return String
 753  */
 754 function wfMsgForContent( $key ) {
 755         global $wgForceUIMsgAsContentMsg;
 756         $args = func_get_args();
 757         array_shift( $args );
 758         $forcontent = true;
 759         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 760                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 761         {
 762                 $forcontent = false;
 763         }
 764         return wfMsgReal( $key, $args, true, $forcontent );
 765 }
 766
 767 /**
 768  * Same as above except doesn't transform the message
 769  *
 770  * @param $key String
 771  * @return String
 772  */
 773 function wfMsgForContentNoTrans( $key ) {
 774         global $wgForceUIMsgAsContentMsg;
 775         $args = func_get_args();
 776         array_shift( $args );
 777         $forcontent = true;
 778         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 779                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 780         {
 781                 $forcontent = false;
 782         }
 783         return wfMsgReal( $key, $args, true, $forcontent, false );
 784 }
 785
 786 /**
 787  * Get a message from the language file, for the UI elements
 788  *
 789  * @deprecated since 1.18; use wfMessage()
 790  */
 791 function wfMsgNoDB( $key ) {
 792         wfDeprecated( __FUNCTION__ );
 793         $args = func_get_args();
 794         array_shift( $args );
 795         return wfMsgReal( $key, $args, false );
 796 }
 797
 798 /**
 799  * Get a message from the language file, for the content
 800  *
 801  * @deprecated since 1.18; use wfMessage()
 802  */
 803 function wfMsgNoDBForContent( $key ) {
 804         wfDeprecated( __FUNCTION__ );
 805         global $wgForceUIMsgAsContentMsg;
 806         $args = func_get_args();
 807         array_shift( $args );
 808         $forcontent = true;
 809         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 810                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 811         {
 812                 $forcontent = false;
 813         }
 814         return wfMsgReal( $key, $args, false, $forcontent );
 815 }
 816
 817
 818 /**
 819  * Really get a message
 820  *
 821  * @param $key String: key to get.
 822  * @param $args
 823  * @param $useDB Boolean
 824  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 825  * @param $transform Boolean: Whether or not to transform the message.
 826  * @return String: the requested message.
 827  */
 828 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 829         wfProfileIn( __METHOD__ );
 830         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 831         $message = wfMsgReplaceArgs( $message, $args );
 832         wfProfileOut( __METHOD__ );
 833         return $message;
 834 }
 835
 836 /**
 837  * This function provides the message source for messages to be edited which are *not* stored in the database.
 838  *
 839  * @deprecated since 1.18; use wfMessage()
 840  * @param $key String
 841  */
 842 function wfMsgWeirdKey( $key ) {
 843         wfDeprecated( __FUNCTION__ );
 844         $source = wfMsgGetKey( $key, false, true, false );
 845         if ( wfEmptyMsg( $key ) ) {
 846                 return '';
 847         } else {
 848                 return $source;
 849         }
 850 }
 851
 852 /**
 853  * Fetch a message string value, but don't replace any keys yet.
 854  *
 855  * @param $key String
 856  * @param $useDB Bool
 857  * @param $langCode String: Code of the language to get the message for, or
 858  *                  behaves as a content language switch if it is a boolean.
 859  * @param $transform Boolean: whether to parse magic words, etc.
 860  * @return string
 861  */
 862 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 863         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 864
 865         $cache = MessageCache::singleton();
 866         $message = $cache->get( $key, $useDB, $langCode );
 867         if( $message === false ) {
 868                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 869         } elseif ( $transform ) {
 870                 $message = $cache->transform( $message );
 871         }
 872         return $message;
 873 }
 874
 875 /**
 876  * Replace message parameter keys on the given formatted output.
 877  *
 878  * @param $message String
 879  * @param $args Array
 880  * @return string
 881  * @private
 882  */
 883 function wfMsgReplaceArgs( $message, $args ) {
 884         # Fix windows line-endings
 885         # Some messages are split with explode("\n", $msg)
 886         $message = str_replace( "\r", '', $message );
 887
 888         // Replace arguments
 889         if ( count( $args ) ) {
 890                 if ( is_array( $args[0] ) ) {
 891                         $args = array_values( $args[0] );
 892                 }
 893                 $replacementKeys = array();
 894                 foreach( $args as $n => $param ) {
 895                         $replacementKeys['$' . ( $n + 1 )] = $param;
 896                 }
 897                 $message = strtr( $message, $replacementKeys );
 898         }
 899
 900         return $message;
 901 }
 902
 903 /**
 904  * Return an HTML-escaped version of a message.
 905  * Parameter replacements, if any, are done *after* the HTML-escaping,
 906  * so parameters may contain HTML (eg links or form controls). Be sure
 907  * to pre-escape them if you really do want plaintext, or just wrap
 908  * the whole thing in htmlspecialchars().
 909  *
 910  * @param $key String
 911  * @param string ... parameters
 912  * @return string
 913  */
 914 function wfMsgHtml( $key ) {
 915         $args = func_get_args();
 916         array_shift( $args );
 917         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 918 }
 919
 920 /**
 921  * Return an HTML version of message
 922  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 923  * so parameters may contain HTML (eg links or form controls). Be sure
 924  * to pre-escape them if you really do want plaintext, or just wrap
 925  * the whole thing in htmlspecialchars().
 926  *
 927  * @param $key String
 928  * @param string ... parameters
 929  * @return string
 930  */
 931 function wfMsgWikiHtml( $key ) {
 932         $args = func_get_args();
 933         array_shift( $args );
 934         return wfMsgReplaceArgs(
 935                 MessageCache::singleton()->parse( wfMsgGetKey( $key, true ), null, /* can't be set to false */ true )->getText(),
 936                 $args );
 937 }
 938
 939 /**
 940  * Returns message in the requested format
 941  * @param $key String: key of the message
 942  * @param $options Array: processing rules. Can take the following options:
 943  *   <i>parse</i>: parses wikitext to HTML
 944  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 945  *       p's added by parser or tidy
 946  *   <i>escape</i>: filters message through htmlspecialchars
 947  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 948  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 949  *   <i>parsemag</i>: transform the message using magic phrases
 950  *   <i>content</i>: fetch message for content language instead of interface
 951  * Also can accept a single associative argument, of the form 'language' => 'xx':
 952  *   <i>language</i>: Language object or language code to fetch message for
 953  *       (overriden by <i>content</i>).
 954  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 955  *
 956  * @return String
 957  */
 958 function wfMsgExt( $key, $options ) {
 959         $args = func_get_args();
 960         array_shift( $args );
 961         array_shift( $args );
 962         $options = (array)$options;
 963
 964         foreach( $options as $arrayKey => $option ) {
 965                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 966                         # An unknown index, neither numeric nor "language"
 967                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 968                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 969                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 970                 'replaceafter', 'parsemag', 'content' ) ) ) {
 971                         # A numeric index with unknown value
 972                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 973                 }
 974         }
 975
 976         if( in_array( 'content', $options, true ) ) {
 977                 $forContent = true;
 978                 $langCode = true;
 979                 $langCodeObj = null;
 980         } elseif( array_key_exists( 'language', $options ) ) {
 981                 $forContent = false;
 982                 $langCode = wfGetLangObj( $options['language'] );
 983                 $langCodeObj = $langCode;
 984         } else {
 985                 $forContent = false;
 986                 $langCode = false;
 987                 $langCodeObj = null;
 988         }
 989
 990         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 991
 992         if( !in_array( 'replaceafter', $options, true ) ) {
 993                 $string = wfMsgReplaceArgs( $string, $args );
 994         }
 995
 996         $messageCache = MessageCache::singleton();
 997         if( in_array( 'parse', $options, true ) ) {
 998                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
 999         } elseif ( in_array( 'parseinline', $options, true ) ) {
1000                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1001                 $m = array();
1002                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1003                         $string = $m[1];
1004                 }
1005         } elseif ( in_array( 'parsemag', $options, true ) ) {
1006                 $string = $messageCache->transform( $string,
1007                                 !$forContent, $langCodeObj );
1008         }
1009
1010         if ( in_array( 'escape', $options, true ) ) {
1011                 $string = htmlspecialchars ( $string );
1012         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1013                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1014         }
1015
1016         if( in_array( 'replaceafter', $options, true ) ) {
1017                 $string = wfMsgReplaceArgs( $string, $args );
1018         }
1019
1020         return $string;
1021 }
1022
1023 /**
1024  * Since wfMsg() and co suck, they don't return false if the message key they
1025  * looked up didn't exist but a XHTML string, this function checks for the
1026  * nonexistance of messages by checking the MessageCache::get() result directly.
1027  *
1028  * @param $key      String: the message key looked up
1029  * @return Boolean True if the message *doesn't* exist.
1030  */
1031 function wfEmptyMsg( $key ) {
1032         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1033 }
1034
1035 /**
1036  * Print an error message and die, returning nonzero to the shell if any.  Plain die()
1037  * fails to return nonzero to the shell if you pass a string.  Entry points may customise
1038  * this function to return a prettier error message, but implementations must not assume
1039  * access to any of the usual MediaWiki infrastructure (AutoLoader, localisation, database,
1040  * etc).  This should not be called directly once $wgFullyInitialised is set; instead,
1041  * throw an exception and let Exception.php handle whether or not it's possible to show
1042  * a prettier error.
1043  *
1044  * @param $msg String
1045  */
1046 if( !function_exists( 'wfDie' ) ){
1047         function wfDie( $msg = '' ) {
1048                 echo $msg;
1049                 die( 1 );
1050         }
1051 }
1052
1053 /**
1054  * Throw a debugging exception. This function previously once exited the process,
1055  * but now throws an exception instead, with similar results.
1056  *
1057  * @param $msg String: message shown when dieing.
1058  */
1059 function wfDebugDieBacktrace( $msg = '' ) {
1060         throw new MWException( $msg );
1061 }
1062
1063 /**
1064  * Fetch server name for use in error reporting etc.
1065  * Use real server name if available, so we know which machine
1066  * in a server farm generated the current page.
1067  *
1068  * @return string
1069  */
1070 function wfHostname() {
1071         static $host;
1072         if ( is_null( $host ) ) {
1073                 if ( function_exists( 'posix_uname' ) ) {
1074                         // This function not present on Windows
1075                         $uname = @posix_uname();
1076                 } else {
1077                         $uname = false;
1078                 }
1079                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1080                         $host = $uname['nodename'];
1081                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1082                         # Windows computer name
1083                         $host = getenv( 'COMPUTERNAME' );
1084                 } else {
1085                         # This may be a virtual server.
1086                         $host = $_SERVER['SERVER_NAME'];
1087                 }
1088         }
1089         return $host;
1090 }
1091
1092 /**
1093  * Returns a HTML comment with the elapsed time since request.
1094  * This method has no side effects.
1095  *
1096  * @return string
1097  */
1098 function wfReportTime() {
1099         global $wgRequestTime, $wgShowHostnames;
1100
1101         $now = wfTime();
1102         $elapsed = $now - $wgRequestTime;
1103
1104         return $wgShowHostnames
1105                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1106                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1107 }
1108
1109 /**
1110  * Safety wrapper for debug_backtrace().
1111  *
1112  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1113  * murky circumstances, which may be triggered in part by stub objects
1114  * or other fancy talkin'.
1115  *
1116  * Will return an empty array if Zend Optimizer is detected or if
1117  * debug_backtrace is disabled, otherwise the output from
1118  * debug_backtrace() (trimmed).
1119  *
1120  * @return array of backtrace information
1121  */
1122 function wfDebugBacktrace() {
1123         static $disabled = null;
1124
1125         if( extension_loaded( 'Zend Optimizer' ) ) {
1126                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1127                 return array();
1128         }
1129
1130         if ( is_null( $disabled ) ) {
1131                 $disabled = false;
1132                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1133                 $functions = array_map( 'trim', $functions );
1134                 $functions = array_map( 'strtolower', $functions );
1135                 if ( in_array( 'debug_backtrace', $functions ) ) {
1136                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1137                         $disabled = true;
1138                 }
1139         }
1140         if ( $disabled ) {
1141                 return array();
1142         }
1143
1144         return array_slice( debug_backtrace(), 1 );
1145 }
1146
1147 /**
1148  * Get a debug backtrace as a string
1149  *
1150  * @return string
1151  */
1152 function wfBacktrace() {
1153         global $wgCommandLineMode;
1154
1155         if ( $wgCommandLineMode ) {
1156                 $msg = '';
1157         } else {
1158                 $msg = "<ul>\n";
1159         }
1160         $backtrace = wfDebugBacktrace();
1161         foreach( $backtrace as $call ) {
1162                 if( isset( $call['file'] ) ) {
1163                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1164                         $file = $f[count( $f ) - 1];
1165                 } else {
1166                         $file = '-';
1167                 }
1168                 if( isset( $call['line'] ) ) {
1169                         $line = $call['line'];
1170                 } else {
1171                         $line = '-';
1172                 }
1173                 if ( $wgCommandLineMode ) {
1174                         $msg .= "$file line $line calls ";
1175                 } else {
1176                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1177                 }
1178                 if( !empty( $call['class'] ) ) {
1179                         $msg .= $call['class'] . '::';
1180                 }
1181                 $msg .= $call['function'] . '()';
1182
1183                 if ( $wgCommandLineMode ) {
1184                         $msg .= "\n";
1185                 } else {
1186                         $msg .= "</li>\n";
1187                 }
1188         }
1189         if ( $wgCommandLineMode ) {
1190                 $msg .= "\n";
1191         } else {
1192                 $msg .= "</ul>\n";
1193         }
1194
1195         return $msg;
1196 }
1197
1198 /**
1199  * Get the name of the function which called this function
1200  *
1201  * @param $level Int
1202  * @return Bool|string
1203  */
1204 function wfGetCaller( $level = 2 ) {
1205         $backtrace = wfDebugBacktrace();
1206         if ( isset( $backtrace[$level] ) ) {
1207                 return wfFormatStackFrame( $backtrace[$level] );
1208         } else {
1209                 $caller = 'unknown';
1210         }
1211         return $caller;
1212 }
1213
1214 /**
1215  * Return a string consisting of callers in the stack. Useful sometimes
1216  * for profiling specific points.
1217  *
1218  * @param $limit The maximum depth of the stack frame to return, or false for
1219  *               the entire stack.
1220  * @return String
1221  */
1222 function wfGetAllCallers( $limit = 3 ) {
1223         $trace = array_reverse( wfDebugBacktrace() );
1224         if ( !$limit || $limit > count( $trace ) - 1 ) {
1225                 $limit = count( $trace ) - 1;
1226         }
1227         $trace = array_slice( $trace, -$limit - 1, $limit );
1228         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1229 }
1230
1231 /**
1232  * Return a string representation of frame
1233  *
1234  * @param $frame Array
1235  * @return Bool
1236  */
1237 function wfFormatStackFrame( $frame ) {
1238         return isset( $frame['class'] ) ?
1239                 $frame['class'] . '::' . $frame['function'] :
1240                 $frame['function'];
1241 }
1242
1243
1244 /* Some generic result counters, pulled out of SearchEngine */
1245
1246
1247 /**
1248  * @todo document
1249  *
1250  * @param $offset Int
1251  * @param $limit Int
1252  * @return String
1253  */
1254 function wfShowingResults( $offset, $limit ) {
1255         global $wgLang;
1256         return wfMsgExt(
1257                 'showingresults',
1258                 array( 'parseinline' ),
1259                 $wgLang->formatNum( $limit ),
1260                 $wgLang->formatNum( $offset + 1 )
1261         );
1262 }
1263
1264 /**
1265  * @todo document
1266  *
1267  * @param $offset Int
1268  * @param $limit Int
1269  * @param $num Int
1270  * @return String
1271  */
1272 function wfShowingResultsNum( $offset, $limit, $num ) {
1273         global $wgLang;
1274         return wfMsgExt(
1275                 'showingresultsnum',
1276                 array( 'parseinline' ),
1277                 $wgLang->formatNum( $limit ),
1278                 $wgLang->formatNum( $offset + 1 ),
1279                 $wgLang->formatNum( $num )
1280         );
1281 }
1282
1283 /**
1284  * Generate (prev x| next x) (20|50|100...) type links for paging
1285  *
1286  * @param $offset String
1287  * @param $limit Integer
1288  * @param $link String
1289  * @param $query String: optional URL query parameter string
1290  * @param $atend Bool: optional param for specified if this is the last page
1291  * @return String
1292  */
1293 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1294         global $wgLang;
1295         $fmtLimit = $wgLang->formatNum( $limit );
1296         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1297         # Get prev/next link display text
1298         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1299         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1300         # Get prev/next link title text
1301         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1302         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1303         # Fetch the title object
1304         if( is_object( $link ) ) {
1305                 $title =& $link;
1306         } else {
1307                 $title = Title::newFromText( $link );
1308                 if( is_null( $title ) ) {
1309                         return false;
1310                 }
1311         }
1312         # Make 'previous' link
1313         if( 0 != $offset ) {
1314                 $po = $offset - $limit;
1315                 $po = max( $po, 0 );
1316                 $q = "limit={$limit}&offset={$po}";
1317                 if( $query != '' ) {
1318                         $q .= '&' . $query;
1319                 }
1320                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1321         } else {
1322                 $plink = $prev;
1323         }
1324         # Make 'next' link
1325         $no = $offset + $limit;
1326         $q = "limit={$limit}&offset={$no}";
1327         if( $query != '' ) {
1328                 $q .= '&' . $query;
1329         }
1330         if( $atend ) {
1331                 $nlink = $next;
1332         } else {
1333                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1334         }
1335         # Make links to set number of items per page
1336         $nums = $wgLang->pipeList( array(
1337                 wfNumLink( $offset, 20, $title, $query ),
1338                 wfNumLink( $offset, 50, $title, $query ),
1339                 wfNumLink( $offset, 100, $title, $query ),
1340                 wfNumLink( $offset, 250, $title, $query ),
1341                 wfNumLink( $offset, 500, $title, $query )
1342         ) );
1343         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1344 }
1345
1346 /**
1347  * Generate links for (20|50|100...) items-per-page links
1348  *
1349  * @param $offset String
1350  * @param $limit Integer
1351  * @param $title Title
1352  * @param $query String: optional URL query parameter string
1353  */
1354 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1355         global $wgLang;
1356         if( $query == '' ) {
1357                 $q = '';
1358         } else {
1359                 $q = $query.'&';
1360         }
1361         $q .= "limit={$limit}&offset={$offset}";
1362         $fmtLimit = $wgLang->formatNum( $limit );
1363         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1364         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1365         return $s;
1366 }
1367
1368 /**
1369  * @todo document
1370  * @todo FIXME: We may want to blacklist some broken browsers
1371  *
1372  * @param $force Bool
1373  * @return bool Whereas client accept gzip compression
1374  */
1375 function wfClientAcceptsGzip( $force = false ) {
1376         static $result = null;
1377         if ( $result === null || $force ) {
1378                 $result = false;
1379                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1380                         # @todo FIXME: We may want to blacklist some broken browsers
1381                         $m = array();
1382                         if( preg_match(
1383                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1384                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1385                                 $m )
1386                         )
1387                         {
1388                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1389                                         $result = false;
1390                                         return $result;
1391                                 }
1392                                 wfDebug( " accepts gzip\n" );
1393                                 $result = true;
1394                         }
1395                 }
1396         }
1397         return $result;
1398 }
1399
1400 /**
1401  * Obtain the offset and limit values from the request string;
1402  * used in special pages
1403  *
1404  * @param $deflimit Int default limit if none supplied
1405  * @param $optionname String Name of a user preference to check against
1406  * @return array
1407  *
1408  */
1409 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1410         global $wgRequest;
1411         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1412 }
1413
1414 /**
1415  * Escapes the given text so that it may be output using addWikiText()
1416  * without any linking, formatting, etc. making its way through. This
1417  * is achieved by substituting certain characters with HTML entities.
1418  * As required by the callers, <nowiki> is not used.
1419  *
1420  * @param $text String: text to be escaped
1421  * @return String
1422  */
1423 function wfEscapeWikiText( $text ) {
1424         $text = strtr( "\n$text", array(
1425                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1426                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1427                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1428                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1429                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1430                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1431         ) );
1432         return substr( $text, 1 );
1433 }
1434
1435 /**
1436  * Get the current unix timetstamp with microseconds.  Useful for profiling
1437  * @return Float
1438  */
1439 function wfTime() {
1440         return microtime( true );
1441 }
1442
1443 /**
1444  * Sets dest to source and returns the original value of dest
1445  * If source is NULL, it just returns the value, it doesn't set the variable
1446  * If force is true, it will set the value even if source is NULL
1447  *
1448  * @param $dest Mixed
1449  * @param $source Mixed
1450  * @param $force Bool
1451  * @return Mixed
1452  */
1453 function wfSetVar( &$dest, $source, $force = false ) {
1454         $temp = $dest;
1455         if ( !is_null( $source ) || $force ) {
1456                 $dest = $source;
1457         }
1458         return $temp;
1459 }
1460
1461 /**
1462  * As for wfSetVar except setting a bit
1463  *
1464  * @param $dest Int
1465  * @param $bit Int
1466  * @param $state Bool
1467  */
1468 function wfSetBit( &$dest, $bit, $state = true ) {
1469         $temp = (bool)( $dest & $bit );
1470         if ( !is_null( $state ) ) {
1471                 if ( $state ) {
1472                         $dest |= $bit;
1473                 } else {
1474                         $dest &= ~$bit;
1475                 }
1476         }
1477         return $temp;
1478 }
1479
1480 /**
1481  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1482  * "days=7&limit=100". Options in the first array override options in the second.
1483  * Options set to "" will not be output.
1484  *
1485  * @param $array1 Array( String|Array )
1486  * @param $array2 Array( String|Array )
1487  * @return String
1488  */
1489 function wfArrayToCGI( $array1, $array2 = null ) {
1490         if ( !is_null( $array2 ) ) {
1491                 $array1 = $array1 + $array2;
1492         }
1493
1494         $cgi = '';
1495         foreach ( $array1 as $key => $value ) {
1496                 if ( $value !== '' ) {
1497                         if ( $cgi != '' ) {
1498                                 $cgi .= '&';
1499                         }
1500                         if ( is_array( $value ) ) {
1501                                 $firstTime = true;
1502                                 foreach ( $value as $v ) {
1503                                         $cgi .= ( $firstTime ? '' : '&') .
1504                                                 urlencode( $key . '[]' ) . '=' .
1505                                                 urlencode( $v );
1506                                         $firstTime = false;
1507                                 }
1508                         } else {
1509                                 if ( is_object( $value ) ) {
1510                                         $value = $value->__toString();
1511                                 }
1512                                 $cgi .= urlencode( $key ) . '=' .
1513                                         urlencode( $value );
1514                         }
1515                 }
1516         }
1517         return $cgi;
1518 }
1519
1520 /**
1521  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1522  * its argument and returns the same string in array form.  This allows compa-
1523  * tibility with legacy functions that accept raw query strings instead of nice
1524  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1525  * valid query strings, or it will explode.
1526  *
1527  * @param $query String: query string
1528  * @return array Array version of input
1529  */
1530 function wfCgiToArray( $query ) {
1531         if( isset( $query[0] ) && $query[0] == '?' ) {
1532                 $query = substr( $query, 1 );
1533         }
1534         $bits = explode( '&', $query );
1535         $ret = array();
1536         foreach( $bits as $bit ) {
1537                 if( $bit === '' ) {
1538                         continue;
1539                 }
1540                 list( $key, $value ) = explode( '=', $bit );
1541                 $key = urldecode( $key );
1542                 $value = urldecode( $value );
1543                 $ret[$key] = $value;
1544         }
1545         return $ret;
1546 }
1547
1548 /**
1549  * Append a query string to an existing URL, which may or may not already
1550  * have query string parameters already. If so, they will be combined.
1551  *
1552  * @param $url String
1553  * @param $query Mixed: string or associative array
1554  * @return string
1555  */
1556 function wfAppendQuery( $url, $query ) {
1557         if ( is_array( $query ) ) {
1558                 $query = wfArrayToCGI( $query );
1559         }
1560         if( $query != '' ) {
1561                 if( false === strpos( $url, '?' ) ) {
1562                         $url .= '?';
1563                 } else {
1564                         $url .= '&';
1565                 }
1566                 $url .= $query;
1567         }
1568         return $url;
1569 }
1570
1571 /**
1572  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1573  * and $wgProto are correct.
1574  *
1575  * @todo this won't work with current-path-relative URLs
1576  * like "subdir/foo.html", etc.
1577  *
1578  * @param $url String: either fully-qualified or a local path + query
1579  * @return string Fully-qualified URL
1580  */
1581 function wfExpandUrl( $url ) {
1582         if( substr( $url, 0, 2 ) == '//' ) {
1583                 global $wgProto;
1584                 return $wgProto . ':' . $url;
1585         } elseif( substr( $url, 0, 1 ) == '/' ) {
1586                 global $wgServer;
1587                 return $wgServer . $url;
1588         } else {
1589                 return $url;
1590         }
1591 }
1592
1593 /**
1594  * Windows-compatible version of escapeshellarg()
1595  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1596  * function puts single quotes in regardless of OS.
1597  *
1598  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1599  * earlier distro releases of PHP)
1600  *
1601  * @param varargs
1602  * @return String
1603  */
1604 function wfEscapeShellArg( ) {
1605         wfInitShellLocale();
1606
1607         $args = func_get_args();
1608         $first = true;
1609         $retVal = '';
1610         foreach ( $args as $arg ) {
1611                 if ( !$first ) {
1612                         $retVal .= ' ';
1613                 } else {
1614                         $first = false;
1615                 }
1616
1617                 if ( wfIsWindows() ) {
1618                         // Escaping for an MSVC-style command line parser and CMD.EXE
1619                         // Refs:
1620                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1621                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1622                         //  * Bug #13518
1623                         //  * CR r63214
1624                         // Double the backslashes before any double quotes. Escape the double quotes.
1625                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1626                         $arg = '';
1627                         $iteration = 0;
1628                         foreach ( $tokens as $token ) {
1629                                 if ( $iteration % 2 == 1 ) {
1630                                         // Delimiter, a double quote preceded by zero or more slashes
1631                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1632                                 } elseif ( $iteration % 4 == 2 ) {
1633                                         // ^ in $token will be outside quotes, need to be escaped
1634                                         $arg .= str_replace( '^', '^^', $token );
1635                                 } else { // $iteration % 4 == 0
1636                                         // ^ in $token will appear inside double quotes, so leave as is
1637                                         $arg .= $token;
1638                                 }
1639                                 $iteration++;
1640                         }
1641                         // Double the backslashes before the end of the string, because
1642                         // we will soon add a quote
1643                         $m = array();
1644                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1645                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1646                         }
1647
1648                         // Add surrounding quotes
1649                         $retVal .= '"' . $arg . '"';
1650                 } else {
1651                         $retVal .= escapeshellarg( $arg );
1652                 }
1653         }
1654         return $retVal;
1655 }
1656
1657 /**
1658  * wfMerge attempts to merge differences between three texts.
1659  * Returns true for a clean merge and false for failure or a conflict.
1660  *
1661  * @param $old String
1662  * @param $mine String
1663  * @param $yours String
1664  * @param $result String
1665  * @return Bool
1666  */
1667 function wfMerge( $old, $mine, $yours, &$result ) {
1668         global $wgDiff3;
1669
1670         # This check may also protect against code injection in
1671         # case of broken installations.
1672         wfSuppressWarnings();
1673         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1674         wfRestoreWarnings();
1675
1676         if( !$haveDiff3 ) {
1677                 wfDebug( "diff3 not found\n" );
1678                 return false;
1679         }
1680
1681         # Make temporary files
1682         $td = wfTempDir();
1683         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1684         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1685         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1686
1687         fwrite( $oldtextFile, $old );
1688         fclose( $oldtextFile );
1689         fwrite( $mytextFile, $mine );
1690         fclose( $mytextFile );
1691         fwrite( $yourtextFile, $yours );
1692         fclose( $yourtextFile );
1693
1694         # Check for a conflict
1695         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1696                 wfEscapeShellArg( $mytextName ) . ' ' .
1697                 wfEscapeShellArg( $oldtextName ) . ' ' .
1698                 wfEscapeShellArg( $yourtextName );
1699         $handle = popen( $cmd, 'r' );
1700
1701         if( fgets( $handle, 1024 ) ) {
1702                 $conflict = true;
1703         } else {
1704                 $conflict = false;
1705         }
1706         pclose( $handle );
1707
1708         # Merge differences
1709         $cmd = $wgDiff3 . ' -a -e --merge ' .
1710                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1711         $handle = popen( $cmd, 'r' );
1712         $result = '';
1713         do {
1714                 $data = fread( $handle, 8192 );
1715                 if ( strlen( $data ) == 0 ) {
1716                         break;
1717                 }
1718                 $result .= $data;
1719         } while ( true );
1720         pclose( $handle );
1721         unlink( $mytextName );
1722         unlink( $oldtextName );
1723         unlink( $yourtextName );
1724
1725         if ( $result === '' && $old !== '' && !$conflict ) {
1726                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1727                 $conflict = true;
1728         }
1729         return !$conflict;
1730 }
1731
1732 /**
1733  * Returns unified plain-text diff of two texts.
1734  * Useful for machine processing of diffs.
1735  *
1736  * @param $before String: the text before the changes.
1737  * @param $after String: the text after the changes.
1738  * @param $params String: command-line options for the diff command.
1739  * @return String: unified diff of $before and $after
1740  */
1741 function wfDiff( $before, $after, $params = '-u' ) {
1742         if ( $before == $after ) {
1743                 return '';
1744         }
1745
1746         global $wgDiff;
1747         wfSuppressWarnings();
1748         $haveDiff = $wgDiff && file_exists( $wgDiff );
1749         wfRestoreWarnings();
1750
1751         # This check may also protect against code injection in
1752         # case of broken installations.
1753         if( !$haveDiff ) {
1754                 wfDebug( "diff executable not found\n" );
1755                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1756                 $format = new UnifiedDiffFormatter();
1757                 return $format->format( $diffs );
1758         }
1759
1760         # Make temporary files
1761         $td = wfTempDir();
1762         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1763         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1764
1765         fwrite( $oldtextFile, $before );
1766         fclose( $oldtextFile );
1767         fwrite( $newtextFile, $after );
1768         fclose( $newtextFile );
1769
1770         // Get the diff of the two files
1771         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1772
1773         $h = popen( $cmd, 'r' );
1774
1775         $diff = '';
1776
1777         do {
1778                 $data = fread( $h, 8192 );
1779                 if ( strlen( $data ) == 0 ) {
1780                         break;
1781                 }
1782                 $diff .= $data;
1783         } while ( true );
1784
1785         // Clean up
1786         pclose( $h );
1787         unlink( $oldtextName );
1788         unlink( $newtextName );
1789
1790         // Kill the --- and +++ lines. They're not useful.
1791         $diff_lines = explode( "\n", $diff );
1792         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1793                 unset( $diff_lines[0] );
1794         }
1795         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1796                 unset( $diff_lines[1] );
1797         }
1798
1799         $diff = implode( "\n", $diff_lines );
1800
1801         return $diff;
1802 }
1803
1804 /**
1805  * A wrapper around the PHP function var_export().
1806  * Either print it or add it to the regular output ($wgOut).
1807  *
1808  * @param $var A PHP variable to dump.
1809  */
1810 function wfVarDump( $var ) {
1811         global $wgOut;
1812         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1813         if ( headers_sent() || !@is_object( $wgOut ) ) {
1814                 print $s;
1815         } else {
1816                 $wgOut->addHTML( $s );
1817         }
1818 }
1819
1820 /**
1821  * Provide a simple HTTP error.
1822  *
1823  * @param $code Int|String
1824  * @param $label String
1825  * @param $desc String
1826  */
1827 function wfHttpError( $code, $label, $desc ) {
1828         global $wgOut;
1829         $wgOut->disable();
1830         header( "HTTP/1.0 $code $label" );
1831         header( "Status: $code $label" );
1832         $wgOut->sendCacheControl();
1833
1834         header( 'Content-type: text/html; charset=utf-8' );
1835         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1836                 '<html><head><title>' .
1837                 htmlspecialchars( $label ) .
1838                 '</title></head><body><h1>' .
1839                 htmlspecialchars( $label ) .
1840                 '</h1><p>' .
1841                 nl2br( htmlspecialchars( $desc ) ) .
1842                 "</p></body></html>\n";
1843 }
1844
1845 /**
1846  * Clear away any user-level output buffers, discarding contents.
1847  *
1848  * Suitable for 'starting afresh', for instance when streaming
1849  * relatively large amounts of data without buffering, or wanting to
1850  * output image files without ob_gzhandler's compression.
1851  *
1852  * The optional $resetGzipEncoding parameter controls suppression of
1853  * the Content-Encoding header sent by ob_gzhandler; by default it
1854  * is left. See comments for wfClearOutputBuffers() for why it would
1855  * be used.
1856  *
1857  * Note that some PHP configuration options may add output buffer
1858  * layers which cannot be removed; these are left in place.
1859  *
1860  * @param $resetGzipEncoding Bool
1861  */
1862 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1863         if( $resetGzipEncoding ) {
1864                 // Suppress Content-Encoding and Content-Length
1865                 // headers from 1.10+s wfOutputHandler
1866                 global $wgDisableOutputCompression;
1867                 $wgDisableOutputCompression = true;
1868         }
1869         while( $status = ob_get_status() ) {
1870                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1871                         // Probably from zlib.output_compression or other
1872                         // PHP-internal setting which can't be removed.
1873                         //
1874                         // Give up, and hope the result doesn't break
1875                         // output behavior.
1876                         break;
1877                 }
1878                 if( !ob_end_clean() ) {
1879                         // Could not remove output buffer handler; abort now
1880                         // to avoid getting in some kind of infinite loop.
1881                         break;
1882                 }
1883                 if( $resetGzipEncoding ) {
1884                         if( $status['name'] == 'ob_gzhandler' ) {
1885                                 // Reset the 'Content-Encoding' field set by this handler
1886                                 // so we can start fresh.
1887                                 if ( function_exists( 'header_remove' ) ) {
1888                                         // Available since PHP 5.3.0
1889                                         header_remove( 'Content-Encoding' );
1890                                 } else {
1891                                         // We need to provide a valid content-coding. See bug 28069
1892                                         header( 'Content-Encoding: identity' );
1893                                 }
1894                                 break;
1895                         }
1896                 }
1897         }
1898 }
1899
1900 /**
1901  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1902  *
1903  * Clear away output buffers, but keep the Content-Encoding header
1904  * produced by ob_gzhandler, if any.
1905  *
1906  * This should be used for HTTP 304 responses, where you need to
1907  * preserve the Content-Encoding header of the real result, but
1908  * also need to suppress the output of ob_gzhandler to keep to spec
1909  * and avoid breaking Firefox in rare cases where the headers and
1910  * body are broken over two packets.
1911  */
1912 function wfClearOutputBuffers() {
1913         wfResetOutputBuffers( false );
1914 }
1915
1916 /**
1917  * Converts an Accept-* header into an array mapping string values to quality
1918  * factors
1919  *
1920  * @param $accept String
1921  * @param $def String default
1922  * @return Array
1923  */
1924 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1925         # No arg means accept anything (per HTTP spec)
1926         if( !$accept ) {
1927                 return array( $def => 1.0 );
1928         }
1929
1930         $prefs = array();
1931
1932         $parts = explode( ',', $accept );
1933
1934         foreach( $parts as $part ) {
1935                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1936                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1937                 $match = array();
1938                 if( !isset( $qpart ) ) {
1939                         $prefs[$value] = 1.0;
1940                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1941                         $prefs[$value] = floatval( $match[1] );
1942                 }
1943         }
1944
1945         return $prefs;
1946 }
1947
1948 /**
1949  * Checks if a given MIME type matches any of the keys in the given
1950  * array. Basic wildcards are accepted in the array keys.
1951  *
1952  * Returns the matching MIME type (or wildcard) if a match, otherwise
1953  * NULL if no match.
1954  *
1955  * @param $type String
1956  * @param $avail Array
1957  * @return string
1958  * @private
1959  */
1960 function mimeTypeMatch( $type, $avail ) {
1961         if( array_key_exists( $type, $avail ) ) {
1962                 return $type;
1963         } else {
1964                 $parts = explode( '/', $type );
1965                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1966                         return $parts[0] . '/*';
1967                 } elseif( array_key_exists( '*/*', $avail ) ) {
1968                         return '*/*';
1969                 } else {
1970                         return null;
1971                 }
1972         }
1973 }
1974
1975 /**
1976  * Returns the 'best' match between a client's requested internet media types
1977  * and the server's list of available types. Each list should be an associative
1978  * array of type to preference (preference is a float between 0.0 and 1.0).
1979  * Wildcards in the types are acceptable.
1980  *
1981  * @param $cprefs Array: client's acceptable type list
1982  * @param $sprefs Array: server's offered types
1983  * @return string
1984  *
1985  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1986  * XXX: generalize to negotiate other stuff
1987  */
1988 function wfNegotiateType( $cprefs, $sprefs ) {
1989         $combine = array();
1990
1991         foreach( array_keys($sprefs) as $type ) {
1992                 $parts = explode( '/', $type );
1993                 if( $parts[1] != '*' ) {
1994                         $ckey = mimeTypeMatch( $type, $cprefs );
1995                         if( $ckey ) {
1996                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1997                         }
1998                 }
1999         }
2000
2001         foreach( array_keys( $cprefs ) as $type ) {
2002                 $parts = explode( '/', $type );
2003                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2004                         $skey = mimeTypeMatch( $type, $sprefs );
2005                         if( $skey ) {
2006                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2007                         }
2008                 }
2009         }
2010
2011         $bestq = 0;
2012         $besttype = null;
2013
2014         foreach( array_keys( $combine ) as $type ) {
2015                 if( $combine[$type] > $bestq ) {
2016                         $besttype = $type;
2017                         $bestq = $combine[$type];
2018                 }
2019         }
2020
2021         return $besttype;
2022 }
2023
2024 /**
2025  * Reference-counted warning suppression
2026  *
2027  * @param $end Bool
2028  */
2029 function wfSuppressWarnings( $end = false ) {
2030         static $suppressCount = 0;
2031         static $originalLevel = false;
2032
2033         if ( $end ) {
2034                 if ( $suppressCount ) {
2035                         --$suppressCount;
2036                         if ( !$suppressCount ) {
2037                                 error_reporting( $originalLevel );
2038                         }
2039                 }
2040         } else {
2041                 if ( !$suppressCount ) {
2042                         // E_DEPRECATED is undefined in PHP 5.2
2043                         if( !defined( 'E_DEPRECATED' ) ){
2044                                 define( 'E_DEPRECATED', 8192 );
2045                         }
2046                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2047                 }
2048                 ++$suppressCount;
2049         }
2050 }
2051
2052 /**
2053  * Restore error level to previous value
2054  */
2055 function wfRestoreWarnings() {
2056         wfSuppressWarnings( true );
2057 }
2058
2059 # Autodetect, convert and provide timestamps of various types
2060
2061 /**
2062  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2063  */
2064 define( 'TS_UNIX', 0 );
2065
2066 /**
2067  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2068  */
2069 define( 'TS_MW', 1 );
2070
2071 /**
2072  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2073  */
2074 define( 'TS_DB', 2 );
2075
2076 /**
2077  * RFC 2822 format, for E-mail and HTTP headers
2078  */
2079 define( 'TS_RFC2822', 3 );
2080
2081 /**
2082  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2083  *
2084  * This is used by Special:Export
2085  */
2086 define( 'TS_ISO_8601', 4 );
2087
2088 /**
2089  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2090  *
2091  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2092  *       DateTime tag and page 36 for the DateTimeOriginal and
2093  *       DateTimeDigitized tags.
2094  */
2095 define( 'TS_EXIF', 5 );
2096
2097 /**
2098  * Oracle format time.
2099  */
2100 define( 'TS_ORACLE', 6 );
2101
2102 /**
2103  * Postgres format time.
2104  */
2105 define( 'TS_POSTGRES', 7 );
2106
2107 /**
2108  * DB2 format time
2109  */
2110 define( 'TS_DB2', 8 );
2111
2112 /**
2113  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2114  */
2115 define( 'TS_ISO_8601_BASIC', 9 );
2116
2117 /**
2118  * Get a timestamp string in one of various formats
2119  *
2120  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2121  *                    function will autodetect which format is supplied and act
2122  *                    accordingly.
2123  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2124  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2125  */
2126 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2127         $uts = 0;
2128         $da = array();
2129         $strtime = '';
2130
2131         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2132                 $uts = time();
2133                 $strtime = "@$uts";
2134         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2135                 # TS_DB
2136         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2137                 # TS_EXIF
2138         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2139                 # TS_MW
2140         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2141                 # TS_UNIX
2142                 $uts = $ts;
2143                 $strtime = "@$ts"; // Undocumented?
2144         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2145                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2146                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2147                                 str_replace( '+00:00', 'UTC', $ts ) );
2148         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2149                 # TS_ISO_8601
2150         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2151                 #TS_ISO_8601_BASIC
2152         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2153                 # TS_POSTGRES
2154         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2155                 # TS_POSTGRES
2156         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2157                 # TS_DB2
2158         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2159                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2160                                                         '[ \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
2161                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2162                 # The regex is a superset of rfc2822 for readability
2163                 $strtime = strtok( $ts, ';' );
2164         } 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 ) ) {
2165                 # TS_RFC850
2166                 $strtime = $ts;
2167         } 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 ) ) {
2168                 # asctime
2169                 $strtime = $ts;
2170         } else {
2171                 # Bogus value...
2172                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2173
2174                 return false;
2175         }
2176
2177         static $formats = array(
2178                 TS_UNIX => 'U',
2179                 TS_MW => 'YmdHis',
2180                 TS_DB => 'Y-m-d H:i:s',
2181                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2182                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2183                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2184                 TS_RFC2822 => 'D, d M Y H:i:s',
2185                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2186                 TS_POSTGRES => 'Y-m-d H:i:s',
2187                 TS_DB2 => 'Y-m-d H:i:s',
2188         );
2189
2190         if ( !isset( $formats[$outputtype] ) ) {
2191                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2192         }
2193
2194         if ( function_exists( "date_create" ) ) {
2195                 if ( count( $da ) ) {
2196                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2197                                 (int)$da[1], (int)$da[2], (int)$da[3],
2198                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2199
2200                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2201                 } elseif ( $strtime ) {
2202                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2203                 } else {
2204                         return false;
2205                 }
2206
2207                 if ( !$d ) {
2208                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2209                         return false;
2210                 }
2211
2212                 $output = $d->format( $formats[$outputtype] );
2213         } else {
2214                 if ( count( $da ) ) {
2215                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2216                         // We may want to handle that explicitly at some point
2217                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2218                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2219                 } elseif ( $strtime ) {
2220                         $uts = strtotime( $strtime );
2221                 }
2222
2223                 if ( $uts === false ) {
2224                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2225                         return false;
2226                 }
2227
2228                 if ( TS_UNIX == $outputtype ) {
2229                         return $uts;
2230                 }
2231                 $output = gmdate( $formats[$outputtype], $uts );
2232         }
2233
2234         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2235                 $output .= ' GMT';
2236         }
2237
2238         return $output;
2239 }
2240
2241 /**
2242  * Return a formatted timestamp, or null if input is null.
2243  * For dealing with nullable timestamp columns in the database.
2244  *
2245  * @param $outputtype Integer
2246  * @param $ts String
2247  * @return String
2248  */
2249 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2250         if( is_null( $ts ) ) {
2251                 return null;
2252         } else {
2253                 return wfTimestamp( $outputtype, $ts );
2254         }
2255 }
2256
2257 /**
2258  * Convenience function; returns MediaWiki timestamp for the present time.
2259  *
2260  * @return string
2261  */
2262 function wfTimestampNow() {
2263         # return NOW
2264         return wfTimestamp( TS_MW, time() );
2265 }
2266
2267 /**
2268  * Check if the operating system is Windows
2269  *
2270  * @return Bool: true if it's Windows, False otherwise.
2271  */
2272 function wfIsWindows() {
2273         static $isWindows = null;
2274         if ( $isWindows === null ) {
2275                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2276         }
2277         return $isWindows;
2278 }
2279
2280 /**
2281  * Check if we are running under HipHop
2282  *
2283  * @return Bool
2284  */
2285 function wfIsHipHop() {
2286         return function_exists( 'hphp_thread_set_warmup_enabled' );
2287 }
2288
2289 /**
2290  * Swap two variables
2291  *
2292  * @param $x Mixed
2293  * @param $y Mixed
2294  */
2295 function swap( &$x, &$y ) {
2296         $z = $x;
2297         $x = $y;
2298         $y = $z;
2299 }
2300
2301 /**
2302  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2303  * TEMP environment variables are then checked in sequence, and if none are set
2304  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2305  * or C:\Windows\Temp for Windows and hope for the best.
2306  * It is common to call it with tempnam().
2307  *
2308  * NOTE: When possible, use instead the tmpfile() function to create
2309  * temporary files to avoid race conditions on file creation, etc.
2310  *
2311  * @return String
2312  */
2313 function wfTempDir() {
2314         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2315                 $tmp = getenv( $var );
2316                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2317                         return $tmp;
2318                 }
2319         }
2320         if( function_exists( 'sys_get_temp_dir' ) ) {
2321                 return sys_get_temp_dir();
2322         }
2323         # Usual defaults
2324         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2325 }
2326
2327 /**
2328  * Make directory, and make all parent directories if they don't exist
2329  *
2330  * @param $dir String: full path to directory to create
2331  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2332  * @param $caller String: optional caller param for debugging.
2333  * @return bool
2334  */
2335 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2336         global $wgDirectoryMode;
2337
2338         if ( !is_null( $caller ) ) {
2339                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2340         }
2341
2342         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2343                 return true;
2344         }
2345
2346         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2347
2348         if ( is_null( $mode ) ) {
2349                 $mode = $wgDirectoryMode;
2350         }
2351
2352         // Turn off the normal warning, we're doing our own below
2353         wfSuppressWarnings();
2354         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2355         wfRestoreWarnings();
2356
2357         if( !$ok ) {
2358                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2359                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2360         }
2361         return $ok;
2362 }
2363
2364 /**
2365  * Increment a statistics counter
2366  *
2367  * @param $key String
2368  * @param $count Int
2369  */
2370 function wfIncrStats( $key, $count = 1 ) {
2371         global $wgStatsMethod;
2372
2373         $count = intval( $count );
2374
2375         if( $wgStatsMethod == 'udp' ) {
2376                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2377                 static $socket;
2378
2379                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2380
2381                 if ( !$socket ) {
2382                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2383                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2384                         socket_sendto(
2385                                 $socket,
2386                                 $statline,
2387                                 strlen( $statline ),
2388                                 0,
2389                                 $wgUDPProfilerHost,
2390                                 $wgUDPProfilerPort
2391                         );
2392                 }
2393                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2394                 wfSuppressWarnings();
2395                 socket_sendto(
2396                         $socket,
2397                         $statline,
2398                         strlen( $statline ),
2399                         0,
2400                         $wgUDPProfilerHost,
2401                         $wgUDPProfilerPort
2402                 );
2403                 wfRestoreWarnings();
2404         } elseif( $wgStatsMethod == 'cache' ) {
2405                 global $wgMemc;
2406                 $key = wfMemcKey( 'stats', $key );
2407                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2408                         $wgMemc->add( $key, $count );
2409                 }
2410         } else {
2411                 // Disabled
2412         }
2413 }
2414
2415 /**
2416  * @param $nr Mixed: the number to format
2417  * @param $acc Integer: the number of digits after the decimal point, default 2
2418  * @param $round Boolean: whether or not to round the value, default true
2419  * @return float
2420  */
2421 function wfPercent( $nr, $acc = 2, $round = true ) {
2422         $ret = sprintf( "%.${acc}f", $nr );
2423         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2424 }
2425
2426 /**
2427  * Find out whether or not a mixed variable exists in a string
2428  *
2429  * @param $needle String
2430  * @param $str String
2431  * @param $insensitive Boolean
2432  * @return Boolean
2433  */
2434 function in_string( $needle, $str, $insensitive = false ) {
2435         $func = 'strpos';
2436         if( $insensitive ) $func = 'stripos';
2437
2438         return $func( $str, $needle ) !== false;
2439 }
2440
2441 function wfSpecialList( $page, $details ) {
2442         global $wgContLang;
2443         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2444         return $page . $details;
2445 }
2446
2447 /**
2448  * Returns a regular expression of url protocols
2449  *
2450  * @return String
2451  */
2452 function wfUrlProtocols() {
2453         global $wgUrlProtocols;
2454
2455         static $retval = null;
2456         if ( !is_null( $retval ) ) {
2457                 return $retval;
2458         }
2459
2460         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2461         // with LocalSettings files from 1.5
2462         if ( is_array( $wgUrlProtocols ) ) {
2463                 $protocols = array();
2464                 foreach ( $wgUrlProtocols as $protocol ) {
2465                         $protocols[] = preg_quote( $protocol, '/' );
2466                 }
2467
2468                 $retval = implode( '|', $protocols );
2469         } else {
2470                 $retval = $wgUrlProtocols;
2471         }
2472         return $retval;
2473 }
2474
2475 /**
2476  * Safety wrapper around ini_get() for boolean settings.
2477  * The values returned from ini_get() are pre-normalized for settings
2478  * set via php.ini or php_flag/php_admin_flag... but *not*
2479  * for those set via php_value/php_admin_value.
2480  *
2481  * It's fairly common for people to use php_value instead of php_flag,
2482  * which can leave you with an 'off' setting giving a false positive
2483  * for code that just takes the ini_get() return value as a boolean.
2484  *
2485  * To make things extra interesting, setting via php_value accepts
2486  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2487  * Unrecognized values go false... again opposite PHP's own coercion
2488  * from string to bool.
2489  *
2490  * Luckily, 'properly' set settings will always come back as '0' or '1',
2491  * so we only have to worry about them and the 'improper' settings.
2492  *
2493  * I frickin' hate PHP... :P
2494  *
2495  * @param $setting String
2496  * @return Bool
2497  */
2498 function wfIniGetBool( $setting ) {
2499         $val = ini_get( $setting );
2500         // 'on' and 'true' can't have whitespace around them, but '1' can.
2501         return strtolower( $val ) == 'on'
2502                 || strtolower( $val ) == 'true'
2503                 || strtolower( $val ) == 'yes'
2504                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2505 }
2506
2507 /**
2508  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2509  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2510  *
2511  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2512  *                          should be omitted
2513  * @param $fileName String Name of the library, if not $extension.suffix
2514  * @return Bool - Whether or not the extension is loaded
2515  */
2516 function wfDl( $extension, $fileName = null ) {
2517         if( extension_loaded( $extension ) ) {
2518                 return true;
2519         }
2520
2521         $canDl = false;
2522         $sapi = php_sapi_name();
2523         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2524                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2525         {
2526                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2527                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2528         }
2529
2530         if( $canDl ) {
2531                 $fileName = $fileName ? $fileName : $extension;
2532                 if( wfIsWindows() ) {
2533                         $fileName = 'php_' . $fileName;
2534                 }
2535                 wfSuppressWarnings();
2536                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2537                 wfRestoreWarnings();
2538         }
2539         return extension_loaded( $extension );
2540 }
2541
2542 /**
2543  * Execute a shell command, with time and memory limits mirrored from the PHP
2544  * configuration if supported.
2545  * @param $cmd String Command line, properly escaped for shell.
2546  * @param &$retval optional, will receive the program's exit code.
2547  *                 (non-zero is usually failure)
2548  * @param $environ Array optional environment variables which should be
2549  *                 added to the executed command environment.
2550  * @return collected stdout as a string (trailing newlines stripped)
2551  */
2552 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2553         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2554
2555         static $disabled;
2556         if ( is_null( $disabled ) ) {
2557                 $disabled = false;
2558                 if( wfIniGetBool( 'safe_mode' ) ) {
2559                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2560                         $disabled = 'safemode';
2561                 } else {
2562                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2563                         $functions = array_map( 'trim', $functions );
2564                         $functions = array_map( 'strtolower', $functions );
2565                         if ( in_array( 'passthru', $functions ) ) {
2566                                 wfDebug( "passthru is in disabled_functions\n" );
2567                                 $disabled = 'passthru';
2568                         }
2569                 }
2570         }
2571         if ( $disabled ) {
2572                 $retval = 1;
2573                 return $disabled == 'safemode' ?
2574                         'Unable to run external programs in safe mode.' :
2575                         'Unable to run external programs, passthru() is disabled.';
2576         }
2577
2578         wfInitShellLocale();
2579
2580         $envcmd = '';
2581         foreach( $environ as $k => $v ) {
2582                 if ( wfIsWindows() ) {
2583                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2584                          * appear in the environment variable, so we must use carat escaping as documented in
2585                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2586                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2587                          * are listed there but doesn't appear to need it.
2588                          */
2589                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2590                 } else {
2591                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2592                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2593                          */
2594                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2595                 }
2596         }
2597         $cmd = $envcmd . $cmd;
2598
2599         if ( wfIsWindows() ) {
2600                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2601                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2602                 {
2603                         # Hack to work around PHP's flawed invocation of cmd.exe
2604                         # http://news.php.net/php.internals/21796
2605                         # Windows 9x doesn't accept any kind of quotes
2606                         $cmd = '"' . $cmd . '"';
2607                 }
2608         } elseif ( php_uname( 's' ) == 'Linux' ) {
2609                 $time = intval( $wgMaxShellTime );
2610                 $mem = intval( $wgMaxShellMemory );
2611                 $filesize = intval( $wgMaxShellFileSize );
2612
2613                 if ( $time > 0 && $mem > 0 ) {
2614                         $script = "$IP/bin/ulimit4.sh";
2615                         if ( is_executable( $script ) ) {
2616                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2617                         }
2618                 }
2619         }
2620         wfDebug( "wfShellExec: $cmd\n" );
2621
2622         $retval = 1; // error by default?
2623         ob_start();
2624         passthru( $cmd, $retval );
2625         $output = ob_get_contents();
2626         ob_end_clean();
2627
2628         if ( $retval == 127 ) {
2629                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2630         }
2631         return $output;
2632 }
2633
2634 /**
2635  * Workaround for http://bugs.php.net/bug.php?id=45132
2636  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2637  */
2638 function wfInitShellLocale() {
2639         static $done = false;
2640         if ( $done ) {
2641                 return;
2642         }
2643         $done = true;
2644         global $wgShellLocale;
2645         if ( !wfIniGetBool( 'safe_mode' ) ) {
2646                 putenv( "LC_CTYPE=$wgShellLocale" );
2647                 setlocale( LC_CTYPE, $wgShellLocale );
2648         }
2649 }
2650
2651 /**
2652  * This function works like "use VERSION" in Perl, the program will die with a
2653  * backtrace if the current version of PHP is less than the version provided
2654  *
2655  * This is useful for extensions which due to their nature are not kept in sync
2656  * with releases, and might depend on other versions of PHP than the main code
2657  *
2658  * Note: PHP might die due to parsing errors in some cases before it ever
2659  *       manages to call this function, such is life
2660  *
2661  * @see perldoc -f use
2662  *
2663  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2664  *                 a float
2665  */
2666 function wfUsePHP( $req_ver ) {
2667         $php_ver = PHP_VERSION;
2668
2669         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2670                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2671         }
2672 }
2673
2674 /**
2675  * This function works like "use VERSION" in Perl except it checks the version
2676  * of MediaWiki, the program will die with a backtrace if the current version
2677  * of MediaWiki is less than the version provided.
2678  *
2679  * This is useful for extensions which due to their nature are not kept in sync
2680  * with releases
2681  *
2682  * @see perldoc -f use
2683  *
2684  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2685  *                 a float
2686  */
2687 function wfUseMW( $req_ver ) {
2688         global $wgVersion;
2689
2690         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2691                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2692         }
2693 }
2694
2695 /**
2696  * Return the final portion of a pathname.
2697  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2698  * http://bugs.php.net/bug.php?id=33898
2699  *
2700  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2701  * We'll consider it so always, as we don't want \s in our Unix paths either.
2702  *
2703  * @param $path String
2704  * @param $suffix String: to remove if present
2705  * @return String
2706  */
2707 function wfBaseName( $path, $suffix = '' ) {
2708         $encSuffix = ( $suffix == '' )
2709                 ? ''
2710                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2711         $matches = array();
2712         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2713                 return $matches[1];
2714         } else {
2715                 return '';
2716         }
2717 }
2718
2719 /**
2720  * Generate a relative path name to the given file.
2721  * May explode on non-matching case-insensitive paths,
2722  * funky symlinks, etc.
2723  *
2724  * @param $path String: absolute destination path including target filename
2725  * @param $from String: Absolute source path, directory only
2726  * @return String
2727  */
2728 function wfRelativePath( $path, $from ) {
2729         // Normalize mixed input on Windows...
2730         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2731         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2732
2733         // Trim trailing slashes -- fix for drive root
2734         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2735         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2736
2737         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2738         $against = explode( DIRECTORY_SEPARATOR, $from );
2739
2740         if( $pieces[0] !== $against[0] ) {
2741                 // Non-matching Windows drive letters?
2742                 // Return a full path.
2743                 return $path;
2744         }
2745
2746         // Trim off common prefix
2747         while( count( $pieces ) && count( $against )
2748                 && $pieces[0] == $against[0] ) {
2749                 array_shift( $pieces );
2750                 array_shift( $against );
2751         }
2752
2753         // relative dots to bump us to the parent
2754         while( count( $against ) ) {
2755                 array_unshift( $pieces, '..' );
2756                 array_shift( $against );
2757         }
2758
2759         array_push( $pieces, wfBaseName( $path ) );
2760
2761         return implode( DIRECTORY_SEPARATOR, $pieces );
2762 }
2763
2764 /**
2765  * parse_url() work-alike, but non-broken.  Differences:
2766  *
2767  * 1) Does not raise warnings on bad URLs (just returns false)
2768  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2769  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2770  *
2771  * @param $url String: a URL to parse
2772  * @return Array: bits of the URL in an associative array, per PHP docs
2773  */
2774 function wfParseUrl( $url ) {
2775         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2776         wfSuppressWarnings();
2777         $bits = parse_url( $url );
2778         wfRestoreWarnings();
2779         if ( !$bits ) {
2780                 return false;
2781         }
2782
2783         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2784         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2785                 $bits['delimiter'] = '://';
2786         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2787                 $bits['delimiter'] = ':';
2788                 // parse_url detects for news: and mailto: the host part of an url as path
2789                 // We have to correct this wrong detection
2790                 if ( isset( $bits['path'] ) ) {
2791                         $bits['host'] = $bits['path'];
2792                         $bits['path'] = '';
2793                 }
2794         } else {
2795                 return false;
2796         }
2797
2798         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
2799         if ( !isset( $bits['host'] ) ) {
2800                 $bits['host'] = '';
2801
2802                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
2803                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
2804                         $bits['path'] = '/' . $bits['path'];
2805                 }
2806         }
2807         return $bits;
2808 }
2809
2810 /**
2811  * Make a URL index, appropriate for the el_index field of externallinks.
2812  *
2813  * @param $url String
2814  * @return String
2815  */
2816 function wfMakeUrlIndex( $url ) {
2817         $bits = wfParseUrl( $url );
2818
2819         // Reverse the labels in the hostname, convert to lower case
2820         // For emails reverse domainpart only
2821         if ( $bits['scheme'] == 'mailto' ) {
2822                 $mailparts = explode( '@', $bits['host'], 2 );
2823                 if ( count( $mailparts ) === 2 ) {
2824                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2825                 } else {
2826                         // No domain specified, don't mangle it
2827                         $domainpart = '';
2828                 }
2829                 $reversedHost = $domainpart . '@' . $mailparts[0];
2830         } else {
2831                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2832         }
2833         // Add an extra dot to the end
2834         // Why? Is it in wrong place in mailto links?
2835         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2836                 $reversedHost .= '.';
2837         }
2838         // Reconstruct the pseudo-URL
2839         $prot = $bits['scheme'];
2840         $index = $prot . $bits['delimiter'] . $reversedHost;
2841         // Leave out user and password. Add the port, path, query and fragment
2842         if ( isset( $bits['port'] ) ) {
2843                 $index .= ':' . $bits['port'];
2844         }
2845         if ( isset( $bits['path'] ) ) {
2846                 $index .= $bits['path'];
2847         } else {
2848                 $index .= '/';
2849         }
2850         if ( isset( $bits['query'] ) ) {
2851                 $index .= '?' . $bits['query'];
2852         }
2853         if ( isset( $bits['fragment'] ) ) {
2854                 $index .= '#' . $bits['fragment'];
2855         }
2856         return $index;
2857 }
2858
2859 /**
2860  * Do any deferred updates and clear the list
2861  *
2862  * @param $commit String: set to 'commit' to commit after every update to
2863  *                prevent lock contention
2864  */
2865 function wfDoUpdates( $commit = '' ) {
2866         global $wgDeferredUpdateList;
2867
2868         wfProfileIn( __METHOD__ );
2869
2870         // No need to get master connections in case of empty updates array
2871         if ( !count( $wgDeferredUpdateList ) ) {
2872                 wfProfileOut( __METHOD__ );
2873                 return;
2874         }
2875
2876         $doCommit = $commit == 'commit';
2877         if ( $doCommit ) {
2878                 $dbw = wfGetDB( DB_MASTER );
2879         }
2880
2881         foreach ( $wgDeferredUpdateList as $update ) {
2882                 $update->doUpdate();
2883
2884                 if ( $doCommit && $dbw->trxLevel() ) {
2885                         $dbw->commit();
2886                 }
2887         }
2888
2889         $wgDeferredUpdateList = array();
2890         wfProfileOut( __METHOD__ );
2891 }
2892
2893 /**
2894  * Convert an arbitrarily-long digit string from one numeric base
2895  * to another, optionally zero-padding to a minimum column width.
2896  *
2897  * Supports base 2 through 36; digit values 10-36 are represented
2898  * as lowercase letters a-z. Input is case-insensitive.
2899  *
2900  * @param $input String: of digits
2901  * @param $sourceBase Integer: 2-36
2902  * @param $destBase Integer: 2-36
2903  * @param $pad Integer: 1 or greater
2904  * @param $lowercase Boolean
2905  * @return String or false on invalid input
2906  */
2907 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2908         $input = strval( $input );
2909         if( $sourceBase < 2 ||
2910                 $sourceBase > 36 ||
2911                 $destBase < 2 ||
2912                 $destBase > 36 ||
2913                 $pad < 1 ||
2914                 $sourceBase != intval( $sourceBase ) ||
2915                 $destBase != intval( $destBase ) ||
2916                 $pad != intval( $pad ) ||
2917                 !is_string( $input ) ||
2918                 $input == '' ) {
2919                 return false;
2920         }
2921         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2922         $inDigits = array();
2923         $outChars = '';
2924
2925         // Decode and validate input string
2926         $input = strtolower( $input );
2927         for( $i = 0; $i < strlen( $input ); $i++ ) {
2928                 $n = strpos( $digitChars, $input[$i] );
2929                 if( $n === false || $n > $sourceBase ) {
2930                         return false;
2931                 }
2932                 $inDigits[] = $n;
2933         }
2934
2935         // Iterate over the input, modulo-ing out an output digit
2936         // at a time until input is gone.
2937         while( count( $inDigits ) ) {
2938                 $work = 0;
2939                 $workDigits = array();
2940
2941                 // Long division...
2942                 foreach( $inDigits as $digit ) {
2943                         $work *= $sourceBase;
2944                         $work += $digit;
2945
2946                         if( $work < $destBase ) {
2947                                 // Gonna need to pull another digit.
2948                                 if( count( $workDigits ) ) {
2949                                         // Avoid zero-padding; this lets us find
2950                                         // the end of the input very easily when
2951                                         // length drops to zero.
2952                                         $workDigits[] = 0;
2953                                 }
2954                         } else {
2955                                 // Finally! Actual division!
2956                                 $workDigits[] = intval( $work / $destBase );
2957
2958                                 // Isn't it annoying that most programming languages
2959                                 // don't have a single divide-and-remainder operator,
2960                                 // even though the CPU implements it that way?
2961                                 $work = $work % $destBase;
2962                         }
2963                 }
2964
2965                 // All that division leaves us with a remainder,
2966                 // which is conveniently our next output digit.
2967                 $outChars .= $digitChars[$work];
2968
2969                 // And we continue!
2970                 $inDigits = $workDigits;
2971         }
2972
2973         while( strlen( $outChars ) < $pad ) {
2974                 $outChars .= '0';
2975         }
2976
2977         return strrev( $outChars );
2978 }
2979
2980 /**
2981  * Create an object with a given name and an array of construct parameters
2982  *
2983  * @param $name String
2984  * @param $p Array: parameters
2985  * @deprecated since 1.18, warnings in 1.19, removal in 1.20
2986  */
2987 function wfCreateObject( $name, $p ) {
2988         wfDeprecated( __FUNCTION__ );
2989         return MWFunction::newObj( $name, $p );
2990 }
2991
2992 function wfHttpOnlySafe() {
2993         global $wgHttpOnlyBlacklist;
2994
2995         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2996                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2997                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2998                                 return false;
2999                         }
3000                 }
3001         }
3002
3003         return true;
3004 }
3005
3006 /**
3007  * Initialise php session
3008  *
3009  * @param $sessionId Bool
3010  */
3011 function wfSetupSession( $sessionId = false ) {
3012         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3013                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3014         if( $wgSessionsInMemcached ) {
3015                 if ( !defined( 'MW_COMPILED' ) ) {
3016                         global $IP;
3017                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3018                 }
3019                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3020                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3021
3022                 // It's necessary to register a shutdown function to call session_write_close(),
3023                 // because by the time the request shutdown function for the session module is
3024                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3025                 // this way are called before object destruction.
3026                 register_shutdown_function( 'memsess_write_close' );
3027         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3028                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3029                 # hasn't already been set to the desired value (that causes errors)
3030                 ini_set( 'session.save_handler', $wgSessionHandler );
3031         }
3032         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3033         wfDebugLog( 'cookie',
3034                 'session_set_cookie_params: "' . implode( '", "',
3035                         array(
3036                                 0,
3037                                 $wgCookiePath,
3038                                 $wgCookieDomain,
3039                                 $wgCookieSecure,
3040                                 $httpOnlySafe ) ) . '"' );
3041         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3042         session_cache_limiter( 'private, must-revalidate' );
3043         if ( $sessionId ) {
3044                 session_id( $sessionId );
3045         }
3046         wfSuppressWarnings();
3047         session_start();
3048         wfRestoreWarnings();
3049 }
3050
3051 /**
3052  * Get an object from the precompiled serialized directory
3053  *
3054  * @param $name String
3055  * @return Mixed: the variable on success, false on failure
3056  */
3057 function wfGetPrecompiledData( $name ) {
3058         global $IP;
3059
3060         $file = "$IP/serialized/$name";
3061         if ( file_exists( $file ) ) {
3062                 $blob = file_get_contents( $file );
3063                 if ( $blob ) {
3064                         return unserialize( $blob );
3065                 }
3066         }
3067         return false;
3068 }
3069
3070 /**
3071  * Get a cache key
3072  *
3073  * @param varargs
3074  * @return String
3075  */
3076 function wfMemcKey( /*... */ ) {
3077         $args = func_get_args();
3078         $key = wfWikiID() . ':' . implode( ':', $args );
3079         $key = str_replace( ' ', '_', $key );
3080         return $key;
3081 }
3082
3083 /**
3084  * Get a cache key for a foreign DB
3085  *
3086  * @param $db String
3087  * @param $prefix String
3088  * @param varargs String
3089  * @return String
3090  */
3091 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3092         $args = array_slice( func_get_args(), 2 );
3093         if ( $prefix ) {
3094                 $key = "$db-$prefix:" . implode( ':', $args );
3095         } else {
3096                 $key = $db . ':' . implode( ':', $args );
3097         }
3098         return $key;
3099 }
3100
3101 /**
3102  * Get an ASCII string identifying this wiki
3103  * This is used as a prefix in memcached keys
3104  *
3105  * @return String
3106  */
3107 function wfWikiID() {
3108         global $wgDBprefix, $wgDBname;
3109         if ( $wgDBprefix ) {
3110                 return "$wgDBname-$wgDBprefix";
3111         } else {
3112                 return $wgDBname;
3113         }
3114 }
3115
3116 /**
3117  * Split a wiki ID into DB name and table prefix
3118  *
3119  * @param $wiki String
3120  * @param $bits String
3121  */
3122 function wfSplitWikiID( $wiki ) {
3123         $bits = explode( '-', $wiki, 2 );
3124         if ( count( $bits ) < 2 ) {
3125                 $bits[] = '';
3126         }
3127         return $bits;
3128 }
3129
3130 /**
3131  * Get a Database object.
3132  *
3133  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3134  *            master (for write queries), DB_SLAVE for potentially lagged read
3135  *            queries, or an integer >= 0 for a particular server.
3136  *
3137  * @param $groups Mixed: query groups. An array of group names that this query
3138  *                belongs to. May contain a single string if the query is only
3139  *                in one group.
3140  *
3141  * @param $wiki String: the wiki ID, or false for the current wiki
3142  *
3143  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3144  * will always return the same object, unless the underlying connection or load
3145  * balancer is manually destroyed.
3146  *
3147  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3148  * updater to ensure that a proper database is being updated.
3149  *
3150  * @return DatabaseBase
3151  */
3152 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3153         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3154 }
3155
3156 /**
3157  * Get a load balancer object.
3158  *
3159  * @param $wiki String: wiki ID, or false for the current wiki
3160  * @return LoadBalancer
3161  */
3162 function wfGetLB( $wiki = false ) {
3163         return wfGetLBFactory()->getMainLB( $wiki );
3164 }
3165
3166 /**
3167  * Get the load balancer factory object
3168  *
3169  * @return LBFactory
3170  */
3171 function &wfGetLBFactory() {
3172         return LBFactory::singleton();
3173 }
3174
3175 /**
3176  * Find a file.
3177  * Shortcut for RepoGroup::singleton()->findFile()
3178  *
3179  * @param $title String or Title object
3180  * @param $options Associative array of options:
3181  *     time:           requested time for an archived image, or false for the
3182  *                     current version. An image object will be returned which was
3183  *                     created at the specified time.
3184  *
3185  *     ignoreRedirect: If true, do not follow file redirects
3186  *
3187  *     private:        If true, return restricted (deleted) files if the current
3188  *                     user is allowed to view them. Otherwise, such files will not
3189  *                     be found.
3190  *
3191  *     bypassCache:    If true, do not use the process-local cache of File objects
3192  *
3193  * @return File, or false if the file does not exist
3194  */
3195 function wfFindFile( $title, $options = array() ) {
3196         return RepoGroup::singleton()->findFile( $title, $options );
3197 }
3198
3199 /**
3200  * Get an object referring to a locally registered file.
3201  * Returns a valid placeholder object if the file does not exist.
3202  *
3203  * @param $title Title or String
3204  * @return File, or null if passed an invalid Title
3205  */
3206 function wfLocalFile( $title ) {
3207         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3208 }
3209
3210 /**
3211  * Should low-performance queries be disabled?
3212  *
3213  * @return Boolean
3214  * @codeCoverageIgnore
3215  */
3216 function wfQueriesMustScale() {
3217         global $wgMiserMode;
3218         return $wgMiserMode
3219                 || ( SiteStats::pages() > 100000
3220                 && SiteStats::edits() > 1000000
3221                 && SiteStats::users() > 10000 );
3222 }
3223
3224 /**
3225  * Get the path to a specified script file, respecting file
3226  * extensions; this is a wrapper around $wgScriptExtension etc.
3227  *
3228  * @param $script String: script filename, sans extension
3229  * @return String
3230  */
3231 function wfScript( $script = 'index' ) {
3232         global $wgScriptPath, $wgScriptExtension;
3233         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3234 }
3235
3236 /**
3237  * Get the script URL.
3238  *
3239  * @return script URL
3240  */
3241 function wfGetScriptUrl() {
3242         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3243                 #
3244                 # as it was called, minus the query string.
3245                 #
3246                 # Some sites use Apache rewrite rules to handle subdomains,
3247                 # and have PHP set up in a weird way that causes PHP_SELF
3248                 # to contain the rewritten URL instead of the one that the
3249                 # outside world sees.
3250                 #
3251                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3252                 # provides containing the "before" URL.
3253                 return $_SERVER['SCRIPT_NAME'];
3254         } else {
3255                 return $_SERVER['URL'];
3256         }
3257 }
3258
3259 /**
3260  * Convenience function converts boolean values into "true"
3261  * or "false" (string) values
3262  *
3263  * @param $value Boolean
3264  * @return String
3265  */
3266 function wfBoolToStr( $value ) {
3267         return $value ? 'true' : 'false';
3268 }
3269
3270 /**
3271  * Load an extension messages file
3272  *
3273  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3274  * @codeCoverageIgnore
3275  */
3276 function wfLoadExtensionMessages() {
3277         wfDeprecated( __FUNCTION__ );
3278 }
3279
3280 /**
3281  * Get a platform-independent path to the null file, e.g. /dev/null
3282  *
3283  * @return string
3284  */
3285 function wfGetNull() {
3286         return wfIsWindows()
3287                 ? 'NUL'
3288                 : '/dev/null';
3289 }
3290
3291 /**
3292  * Throws a warning that $function is deprecated
3293  *
3294  * @param $function String
3295  * @return null
3296  */
3297 function wfDeprecated( $function ) {
3298         static $functionsWarned = array();
3299         if ( !isset( $functionsWarned[$function] ) ) {
3300                 $functionsWarned[$function] = true;
3301                 wfWarn( "Use of $function is deprecated.", 2 );
3302         }
3303 }
3304
3305 /**
3306  * Send a warning either to the debug log or in a PHP error depending on
3307  * $wgDevelopmentWarnings
3308  *
3309  * @param $msg String: message to send
3310  * @param $callerOffset Integer: number of items to go back in the backtrace to
3311  *        find the correct caller (1 = function calling wfWarn, ...)
3312  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3313  *        is true
3314  */
3315 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3316         global $wgDevelopmentWarnings;
3317
3318         $callers = wfDebugBacktrace();
3319         if ( isset( $callers[$callerOffset + 1] ) ) {
3320                 $callerfunc = $callers[$callerOffset + 1];
3321                 $callerfile = $callers[$callerOffset];
3322                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3323                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3324                 } else {
3325                         $file = '(internal function)';
3326                 }
3327                 $func = '';
3328                 if ( isset( $callerfunc['class'] ) ) {
3329                         $func .= $callerfunc['class'] . '::';
3330                 }
3331                 if ( isset( $callerfunc['function'] ) ) {
3332                         $func .= $callerfunc['function'];
3333                 }
3334                 $msg .= " [Called from $func in $file]";
3335         }
3336
3337         if ( $wgDevelopmentWarnings ) {
3338                 trigger_error( $msg, $level );
3339         } else {
3340                 wfDebug( "$msg\n" );
3341         }
3342 }
3343
3344 /**
3345  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3346  * and waiting for it to go down, this waits for the slaves to catch up to the
3347  * master position. Use this when updating very large numbers of rows, as
3348  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3349  * a no-op if there are no slaves.
3350  *
3351  * @param $maxLag Integer (deprecated)
3352  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3353  * @return null
3354  */
3355 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3356         $lb = wfGetLB( $wiki );
3357         // bug 27975 - Don't try to wait for slaves if there are none
3358         // Prevents permission error when getting master position
3359         if ( $lb->getServerCount() > 1 ) {
3360                 $dbw = $lb->getConnection( DB_MASTER );
3361                 $pos = $dbw->getMasterPos();
3362                 $lb->waitForAll( $pos );
3363         }
3364 }
3365
3366 /**
3367  * Used to be used for outputting text in the installer/updater
3368  * @deprecated since 1.18, warnings in 1.19, remove in 1.20
3369  */
3370 function wfOut( $s ) {
3371         wfDeprecated( __METHOD__ );
3372         global $wgCommandLineMode;
3373         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3374                 echo $s;
3375         } else {
3376                 echo htmlspecialchars( $s );
3377         }
3378         flush();
3379 }
3380
3381 /**
3382  * Count down from $n to zero on the terminal, with a one-second pause
3383  * between showing each number. For use in command-line scripts.
3384  * @codeCoverageIgnore
3385  */
3386 function wfCountDown( $n ) {
3387         for ( $i = $n; $i >= 0; $i-- ) {
3388                 if ( $i != $n ) {
3389                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3390                 }
3391                 echo $i;
3392                 flush();
3393                 if ( $i ) {
3394                         sleep( 1 );
3395                 }
3396         }
3397         echo "\n";
3398 }
3399
3400 /**
3401  * Generate a random 32-character hexadecimal token.
3402  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3403  *              characters before hashing.
3404  * @return string
3405  * @codeCoverageIgnore
3406  */
3407 function wfGenerateToken( $salt = '' ) {
3408         $salt = serialize( $salt );
3409         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3410 }
3411
3412 /**
3413  * Replace all invalid characters with -
3414  *
3415  * @param $name Mixed: filename to process
3416  * @return String
3417  */
3418 function wfStripIllegalFilenameChars( $name ) {
3419         global $wgIllegalFileChars;
3420         $name = wfBaseName( $name );
3421         $name = preg_replace(
3422                 "/[^" . Title::legalChars() . "]" .
3423                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3424                         "/",
3425                 '-',
3426                 $name
3427         );
3428         return $name;
3429 }
3430
3431 /**
3432  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3433  *
3434  * @return Integer value memory was set to.
3435  */
3436 function wfMemoryLimit() {
3437         global $wgMemoryLimit;
3438         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3439         if( $memlimit != -1 ) {
3440                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3441                 if( $conflimit == -1 ) {
3442                         wfDebug( "Removing PHP's memory limit\n" );
3443                         wfSuppressWarnings();
3444                         ini_set( 'memory_limit', $conflimit );
3445                         wfRestoreWarnings();
3446                         return $conflimit;
3447                 } elseif ( $conflimit > $memlimit ) {
3448                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3449                         wfSuppressWarnings();
3450                         ini_set( 'memory_limit', $conflimit );
3451                         wfRestoreWarnings();
3452                         return $conflimit;
3453                 }
3454         }
3455         return $memlimit;
3456 }
3457
3458 /**
3459  * Converts shorthand byte notation to integer form
3460  *
3461  * @param $string String
3462  * @return Integer
3463  */
3464 function wfShorthandToInteger( $string = '' ) {
3465         $string = trim( $string );
3466         if( $string === '' ) {
3467                 return -1;
3468         }
3469         $last = $string[strlen( $string ) - 1];
3470         $val = intval( $string );
3471         switch( $last ) {
3472                 case 'g':
3473                 case 'G':
3474                         $val *= 1024;
3475                         // break intentionally missing
3476                 case 'm':
3477                 case 'M':
3478                         $val *= 1024;
3479                         // break intentionally missing
3480                 case 'k':
3481                 case 'K':
3482                         $val *= 1024;
3483         }
3484
3485         return $val;
3486 }
3487
3488 /**
3489  * Get the normalised IETF language tag
3490  * See unit test for examples.
3491  *
3492  * @param $code String: The language code.
3493  * @return $langCode String: The language code which complying with BCP 47 standards.
3494  */
3495 function wfBCP47( $code ) {
3496         $codeSegment = explode( '-', $code );
3497         $codeBCP = array();
3498         foreach ( $codeSegment as $segNo => $seg ) {
3499                 if ( count( $codeSegment ) > 0 ) {
3500                         // when previous segment is x, it is a private segment and should be lc
3501                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3502                                 $codeBCP[$segNo] = strtolower( $seg );
3503                         // ISO 3166 country code
3504                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3505                                 $codeBCP[$segNo] = strtoupper( $seg );
3506                         // ISO 15924 script code
3507                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3508                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3509                         // Use lowercase for other cases
3510                         } else {
3511                                 $codeBCP[$segNo] = strtolower( $seg );
3512                         }
3513                 } else {
3514                 // Use lowercase for single segment
3515                         $codeBCP[$segNo] = strtolower( $seg );
3516                 }
3517         }
3518         $langCode = implode( '-', $codeBCP );
3519         return $langCode;
3520 }
3521
3522 /**
3523  * Get a cache object.
3524  *
3525  * @param integer $inputType Cache type, one the the CACHE_* constants.
3526  * @return BagOStuff
3527  */
3528 function wfGetCache( $inputType ) {
3529         return ObjectCache::getInstance( $inputType );
3530 }
3531
3532 /**
3533  * Get the main cache object
3534  *
3535  * @return BagOStuff
3536  */
3537 function wfGetMainCache() {
3538         global $wgMainCacheType;
3539         return ObjectCache::getInstance( $wgMainCacheType );
3540 }
3541
3542 /**
3543  * Get the cache object used by the message cache
3544  *
3545  * @return BagOStuff
3546  */
3547 function wfGetMessageCacheStorage() {
3548         global $wgMessageCacheType;
3549         return ObjectCache::getInstance( $wgMessageCacheType );
3550 }
3551
3552 /**
3553  * Get the cache object used by the parser cache
3554  *
3555  * @return BagOStuff
3556  */
3557 function wfGetParserCacheStorage() {
3558         global $wgParserCacheType;
3559         return ObjectCache::getInstance( $wgParserCacheType );
3560 }
3561
3562 /**
3563  * Call hook functions defined in $wgHooks
3564  *
3565  * @param $event String: event name
3566  * @param $args Array: parameters passed to hook functions
3567  * @return Boolean
3568  */
3569 function wfRunHooks( $event, $args = array() ) {
3570         return Hooks::run( $event, $args );
3571 }