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  * Parameters to the message, which can be used to insert variable text into
 709  * it, can be passed to this function in the following formats:
 710  * - One per argument, starting at the second parameter
 711  * - As an array in the second parameter
 712  * These are not shown in the function definition.
 713  *
 714  * @return String
 715  */
 716 function wfMsg( $key ) {
 717         $args = func_get_args();
 718         array_shift( $args );
 719         return wfMsgReal( $key, $args, true );
 720 }
 721
 722 /**
 723  * Same as above except doesn't transform the message
 724  *
 725  * @param $key String
 726  * @return String
 727  */
 728 function wfMsgNoTrans( $key ) {
 729         $args = func_get_args();
 730         array_shift( $args );
 731         return wfMsgReal( $key, $args, true, false, false );
 732 }
 733
 734 /**
 735  * Get a message from anywhere, for the current global language
 736  * set with $wgLanguageCode.
 737  *
 738  * Use this if the message should NOT change dependent on the
 739  * language set in the user's preferences. This is the case for
 740  * most text written into logs, as well as link targets (such as
 741  * the name of the copyright policy page). Link titles, on the
 742  * other hand, should be shown in the UI language.
 743  *
 744  * Note that MediaWiki allows users to change the user interface
 745  * language in their preferences, but a single installation
 746  * typically only contains content in one language.
 747  *
 748  * Be wary of this distinction: If you use wfMsg() where you should
 749  * use wfMsgForContent(), a user of the software may have to
 750  * customize potentially hundreds of messages in
 751  * order to, e.g., fix a link in every possible language.
 752  *
 753  * @param $key String: lookup key for the message, usually
 754  *     defined in languages/Language.php
 755  * @return String
 756  */
 757 function wfMsgForContent( $key ) {
 758         global $wgForceUIMsgAsContentMsg;
 759         $args = func_get_args();
 760         array_shift( $args );
 761         $forcontent = true;
 762         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 763                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 764         {
 765                 $forcontent = false;
 766         }
 767         return wfMsgReal( $key, $args, true, $forcontent );
 768 }
 769
 770 /**
 771  * Same as above except doesn't transform the message
 772  *
 773  * @param $key String
 774  * @return String
 775  */
 776 function wfMsgForContentNoTrans( $key ) {
 777         global $wgForceUIMsgAsContentMsg;
 778         $args = func_get_args();
 779         array_shift( $args );
 780         $forcontent = true;
 781         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 782                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 783         {
 784                 $forcontent = false;
 785         }
 786         return wfMsgReal( $key, $args, true, $forcontent, false );
 787 }
 788
 789 /**
 790  * Get a message from the language file, for the UI elements
 791  *
 792  * @deprecated since 1.18; use wfMessage()
 793  */
 794 function wfMsgNoDB( $key ) {
 795         wfDeprecated( __FUNCTION__ );
 796         $args = func_get_args();
 797         array_shift( $args );
 798         return wfMsgReal( $key, $args, false );
 799 }
 800
 801 /**
 802  * Get a message from the language file, for the content
 803  *
 804  * @deprecated since 1.18; use wfMessage()
 805  */
 806 function wfMsgNoDBForContent( $key ) {
 807         wfDeprecated( __FUNCTION__ );
 808         global $wgForceUIMsgAsContentMsg;
 809         $args = func_get_args();
 810         array_shift( $args );
 811         $forcontent = true;
 812         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 813                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 814         {
 815                 $forcontent = false;
 816         }
 817         return wfMsgReal( $key, $args, false, $forcontent );
 818 }
 819
 820
 821 /**
 822  * Really get a message
 823  *
 824  * @param $key String: key to get.
 825  * @param $args
 826  * @param $useDB Boolean
 827  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 828  * @param $transform Boolean: Whether or not to transform the message.
 829  * @return String: the requested message.
 830  */
 831 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 832         wfProfileIn( __METHOD__ );
 833         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 834         $message = wfMsgReplaceArgs( $message, $args );
 835         wfProfileOut( __METHOD__ );
 836         return $message;
 837 }
 838
 839 /**
 840  * This function provides the message source for messages to be edited which are *not* stored in the database.
 841  *
 842  * @deprecated since 1.18; use wfMessage()
 843  * @param $key String
 844  */
 845 function wfMsgWeirdKey( $key ) {
 846         wfDeprecated( __FUNCTION__ );
 847         $source = wfMsgGetKey( $key, false, true, false );
 848         if ( wfEmptyMsg( $key ) ) {
 849                 return '';
 850         } else {
 851                 return $source;
 852         }
 853 }
 854
 855 /**
 856  * Fetch a message string value, but don't replace any keys yet.
 857  *
 858  * @param $key String
 859  * @param $useDB Bool
 860  * @param $langCode String: Code of the language to get the message for, or
 861  *                  behaves as a content language switch if it is a boolean.
 862  * @param $transform Boolean: whether to parse magic words, etc.
 863  * @return string
 864  */
 865 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 866         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 867
 868         $cache = MessageCache::singleton();
 869         $message = $cache->get( $key, $useDB, $langCode );
 870         if( $message === false ) {
 871                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 872         } elseif ( $transform ) {
 873                 $message = $cache->transform( $message );
 874         }
 875         return $message;
 876 }
 877
 878 /**
 879  * Replace message parameter keys on the given formatted output.
 880  *
 881  * @param $message String
 882  * @param $args Array
 883  * @return string
 884  * @private
 885  */
 886 function wfMsgReplaceArgs( $message, $args ) {
 887         # Fix windows line-endings
 888         # Some messages are split with explode("\n", $msg)
 889         $message = str_replace( "\r", '', $message );
 890
 891         // Replace arguments
 892         if ( count( $args ) ) {
 893                 if ( is_array( $args[0] ) ) {
 894                         $args = array_values( $args[0] );
 895                 }
 896                 $replacementKeys = array();
 897                 foreach( $args as $n => $param ) {
 898                         $replacementKeys['$' . ( $n + 1 )] = $param;
 899                 }
 900                 $message = strtr( $message, $replacementKeys );
 901         }
 902
 903         return $message;
 904 }
 905
 906 /**
 907  * Return an HTML-escaped version of a message.
 908  * Parameter replacements, if any, are done *after* the HTML-escaping,
 909  * so parameters may contain HTML (eg links or form controls). Be sure
 910  * to pre-escape them if you really do want plaintext, or just wrap
 911  * the whole thing in htmlspecialchars().
 912  *
 913  * @param $key String
 914  * @param string ... parameters
 915  * @return string
 916  */
 917 function wfMsgHtml( $key ) {
 918         $args = func_get_args();
 919         array_shift( $args );
 920         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 921 }
 922
 923 /**
 924  * Return an HTML version of message
 925  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 926  * so parameters may contain HTML (eg links or form controls). Be sure
 927  * to pre-escape them if you really do want plaintext, or just wrap
 928  * the whole thing in htmlspecialchars().
 929  *
 930  * @param $key String
 931  * @param string ... parameters
 932  * @return string
 933  */
 934 function wfMsgWikiHtml( $key ) {
 935         $args = func_get_args();
 936         array_shift( $args );
 937         return wfMsgReplaceArgs(
 938                 MessageCache::singleton()->parse( wfMsgGetKey( $key, true ), null, /* can't be set to false */ true )->getText(),
 939                 $args );
 940 }
 941
 942 /**
 943  * Returns message in the requested format
 944  * @param $key String: key of the message
 945  * @param $options Array: processing rules. Can take the following options:
 946  *   <i>parse</i>: parses wikitext to HTML
 947  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 948  *       p's added by parser or tidy
 949  *   <i>escape</i>: filters message through htmlspecialchars
 950  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 951  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 952  *   <i>parsemag</i>: transform the message using magic phrases
 953  *   <i>content</i>: fetch message for content language instead of interface
 954  * Also can accept a single associative argument, of the form 'language' => 'xx':
 955  *   <i>language</i>: Language object or language code to fetch message for
 956  *       (overriden by <i>content</i>).
 957  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 958  *
 959  * @return String
 960  */
 961 function wfMsgExt( $key, $options ) {
 962         $args = func_get_args();
 963         array_shift( $args );
 964         array_shift( $args );
 965         $options = (array)$options;
 966
 967         foreach( $options as $arrayKey => $option ) {
 968                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 969                         # An unknown index, neither numeric nor "language"
 970                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 971                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 972                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 973                 'replaceafter', 'parsemag', 'content' ) ) ) {
 974                         # A numeric index with unknown value
 975                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 976                 }
 977         }
 978
 979         if( in_array( 'content', $options, true ) ) {
 980                 $forContent = true;
 981                 $langCode = true;
 982                 $langCodeObj = null;
 983         } elseif( array_key_exists( 'language', $options ) ) {
 984                 $forContent = false;
 985                 $langCode = wfGetLangObj( $options['language'] );
 986                 $langCodeObj = $langCode;
 987         } else {
 988                 $forContent = false;
 989                 $langCode = false;
 990                 $langCodeObj = null;
 991         }
 992
 993         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 994
 995         if( !in_array( 'replaceafter', $options, true ) ) {
 996                 $string = wfMsgReplaceArgs( $string, $args );
 997         }
 998
 999         $messageCache = MessageCache::singleton();
1000         if( in_array( 'parse', $options, true ) ) {
1001                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1002         } elseif ( in_array( 'parseinline', $options, true ) ) {
1003                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1004                 $m = array();
1005                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1006                         $string = $m[1];
1007                 }
1008         } elseif ( in_array( 'parsemag', $options, true ) ) {
1009                 $string = $messageCache->transform( $string,
1010                                 !$forContent, $langCodeObj );
1011         }
1012
1013         if ( in_array( 'escape', $options, true ) ) {
1014                 $string = htmlspecialchars ( $string );
1015         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1016                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1017         }
1018
1019         if( in_array( 'replaceafter', $options, true ) ) {
1020                 $string = wfMsgReplaceArgs( $string, $args );
1021         }
1022
1023         return $string;
1024 }
1025
1026 /**
1027  * Since wfMsg() and co suck, they don't return false if the message key they
1028  * looked up didn't exist but a XHTML string, this function checks for the
1029  * nonexistance of messages by checking the MessageCache::get() result directly.
1030  *
1031  * @param $key      String: the message key looked up
1032  * @return Boolean True if the message *doesn't* exist.
1033  */
1034 function wfEmptyMsg( $key ) {
1035         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1036 }
1037
1038 /**
1039  * Print an error message and die, returning nonzero to the shell if any.  Plain die()
1040  * fails to return nonzero to the shell if you pass a string.  Entry points may customise
1041  * this function to return a prettier error message, but implementations must not assume
1042  * access to any of the usual MediaWiki infrastructure (AutoLoader, localisation, database,
1043  * etc).  This should not be called directly once $wgFullyInitialised is set; instead,
1044  * throw an exception and let Exception.php handle whether or not it's possible to show
1045  * a prettier error.
1046  *
1047  * @param $msg String
1048  */
1049 if( !function_exists( 'wfDie' ) ){
1050         function wfDie( $msg = '' ) {
1051                 echo $msg;
1052                 die( 1 );
1053         }
1054 }
1055
1056 /**
1057  * Throw a debugging exception. This function previously once exited the process,
1058  * but now throws an exception instead, with similar results.
1059  *
1060  * @param $msg String: message shown when dieing.
1061  */
1062 function wfDebugDieBacktrace( $msg = '' ) {
1063         throw new MWException( $msg );
1064 }
1065
1066 /**
1067  * Fetch server name for use in error reporting etc.
1068  * Use real server name if available, so we know which machine
1069  * in a server farm generated the current page.
1070  *
1071  * @return string
1072  */
1073 function wfHostname() {
1074         static $host;
1075         if ( is_null( $host ) ) {
1076                 if ( function_exists( 'posix_uname' ) ) {
1077                         // This function not present on Windows
1078                         $uname = posix_uname();
1079                 } else {
1080                         $uname = false;
1081                 }
1082                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1083                         $host = $uname['nodename'];
1084                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1085                         # Windows computer name
1086                         $host = getenv( 'COMPUTERNAME' );
1087                 } else {
1088                         # This may be a virtual server.
1089                         $host = $_SERVER['SERVER_NAME'];
1090                 }
1091         }
1092         return $host;
1093 }
1094
1095 /**
1096  * Returns a HTML comment with the elapsed time since request.
1097  * This method has no side effects.
1098  *
1099  * @return string
1100  */
1101 function wfReportTime() {
1102         global $wgRequestTime, $wgShowHostnames;
1103
1104         $now = wfTime();
1105         $elapsed = $now - $wgRequestTime;
1106
1107         return $wgShowHostnames
1108                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1109                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1110 }
1111
1112 /**
1113  * Safety wrapper for debug_backtrace().
1114  *
1115  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1116  * murky circumstances, which may be triggered in part by stub objects
1117  * or other fancy talkin'.
1118  *
1119  * Will return an empty array if Zend Optimizer is detected or if
1120  * debug_backtrace is disabled, otherwise the output from
1121  * debug_backtrace() (trimmed).
1122  *
1123  * @return array of backtrace information
1124  */
1125 function wfDebugBacktrace() {
1126         static $disabled = null;
1127
1128         if( extension_loaded( 'Zend Optimizer' ) ) {
1129                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1130                 return array();
1131         }
1132
1133         if ( is_null( $disabled ) ) {
1134                 $disabled = false;
1135                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1136                 $functions = array_map( 'trim', $functions );
1137                 $functions = array_map( 'strtolower', $functions );
1138                 if ( in_array( 'debug_backtrace', $functions ) ) {
1139                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1140                         $disabled = true;
1141                 }
1142         }
1143         if ( $disabled ) {
1144                 return array();
1145         }
1146
1147         return array_slice( debug_backtrace(), 1 );
1148 }
1149
1150 /**
1151  * Get a debug backtrace as a string
1152  *
1153  * @return string
1154  */
1155 function wfBacktrace() {
1156         global $wgCommandLineMode;
1157
1158         if ( $wgCommandLineMode ) {
1159                 $msg = '';
1160         } else {
1161                 $msg = "<ul>\n";
1162         }
1163         $backtrace = wfDebugBacktrace();
1164         foreach( $backtrace as $call ) {
1165                 if( isset( $call['file'] ) ) {
1166                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1167                         $file = $f[count( $f ) - 1];
1168                 } else {
1169                         $file = '-';
1170                 }
1171                 if( isset( $call['line'] ) ) {
1172                         $line = $call['line'];
1173                 } else {
1174                         $line = '-';
1175                 }
1176                 if ( $wgCommandLineMode ) {
1177                         $msg .= "$file line $line calls ";
1178                 } else {
1179                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1180                 }
1181                 if( !empty( $call['class'] ) ) {
1182                         $msg .= $call['class'] . '::';
1183                 }
1184                 $msg .= $call['function'] . '()';
1185
1186                 if ( $wgCommandLineMode ) {
1187                         $msg .= "\n";
1188                 } else {
1189                         $msg .= "</li>\n";
1190                 }
1191         }
1192         if ( $wgCommandLineMode ) {
1193                 $msg .= "\n";
1194         } else {
1195                 $msg .= "</ul>\n";
1196         }
1197
1198         return $msg;
1199 }
1200
1201 /**
1202  * Get the name of the function which called this function
1203  *
1204  * @param $level Int
1205  * @return Bool|string
1206  */
1207 function wfGetCaller( $level = 2 ) {
1208         $backtrace = wfDebugBacktrace();
1209         if ( isset( $backtrace[$level] ) ) {
1210                 return wfFormatStackFrame( $backtrace[$level] );
1211         } else {
1212                 $caller = 'unknown';
1213         }
1214         return $caller;
1215 }
1216
1217 /**
1218  * Return a string consisting of callers in the stack. Useful sometimes
1219  * for profiling specific points.
1220  *
1221  * @param $limit The maximum depth of the stack frame to return, or false for
1222  *               the entire stack.
1223  * @return String
1224  */
1225 function wfGetAllCallers( $limit = 3 ) {
1226         $trace = array_reverse( wfDebugBacktrace() );
1227         if ( !$limit || $limit > count( $trace ) - 1 ) {
1228                 $limit = count( $trace ) - 1;
1229         }
1230         $trace = array_slice( $trace, -$limit - 1, $limit );
1231         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1232 }
1233
1234 /**
1235  * Return a string representation of frame
1236  *
1237  * @param $frame Array
1238  * @return Bool
1239  */
1240 function wfFormatStackFrame( $frame ) {
1241         return isset( $frame['class'] ) ?
1242                 $frame['class'] . '::' . $frame['function'] :
1243                 $frame['function'];
1244 }
1245
1246
1247 /* Some generic result counters, pulled out of SearchEngine */
1248
1249
1250 /**
1251  * @todo document
1252  *
1253  * @param $offset Int
1254  * @param $limit Int
1255  * @return String
1256  */
1257 function wfShowingResults( $offset, $limit ) {
1258         global $wgLang;
1259         return wfMsgExt(
1260                 'showingresults',
1261                 array( 'parseinline' ),
1262                 $wgLang->formatNum( $limit ),
1263                 $wgLang->formatNum( $offset + 1 )
1264         );
1265 }
1266
1267 /**
1268  * @todo document
1269  *
1270  * @param $offset Int
1271  * @param $limit Int
1272  * @param $num Int
1273  * @return String
1274  */
1275 function wfShowingResultsNum( $offset, $limit, $num ) {
1276         global $wgLang;
1277         return wfMsgExt(
1278                 'showingresultsnum',
1279                 array( 'parseinline' ),
1280                 $wgLang->formatNum( $limit ),
1281                 $wgLang->formatNum( $offset + 1 ),
1282                 $wgLang->formatNum( $num )
1283         );
1284 }
1285
1286 /**
1287  * Generate (prev x| next x) (20|50|100...) type links for paging
1288  *
1289  * @param $offset String
1290  * @param $limit Integer
1291  * @param $link String
1292  * @param $query String: optional URL query parameter string
1293  * @param $atend Bool: optional param for specified if this is the last page
1294  * @return String
1295  */
1296 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1297         global $wgLang;
1298         $fmtLimit = $wgLang->formatNum( $limit );
1299         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1300         # Get prev/next link display text
1301         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1302         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1303         # Get prev/next link title text
1304         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1305         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1306         # Fetch the title object
1307         if( is_object( $link ) ) {
1308                 $title =& $link;
1309         } else {
1310                 $title = Title::newFromText( $link );
1311                 if( is_null( $title ) ) {
1312                         return false;
1313                 }
1314         }
1315         # Make 'previous' link
1316         if( 0 != $offset ) {
1317                 $po = $offset - $limit;
1318                 $po = max( $po, 0 );
1319                 $q = "limit={$limit}&offset={$po}";
1320                 if( $query != '' ) {
1321                         $q .= '&' . $query;
1322                 }
1323                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1324         } else {
1325                 $plink = $prev;
1326         }
1327         # Make 'next' link
1328         $no = $offset + $limit;
1329         $q = "limit={$limit}&offset={$no}";
1330         if( $query != '' ) {
1331                 $q .= '&' . $query;
1332         }
1333         if( $atend ) {
1334                 $nlink = $next;
1335         } else {
1336                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1337         }
1338         # Make links to set number of items per page
1339         $nums = $wgLang->pipeList( array(
1340                 wfNumLink( $offset, 20, $title, $query ),
1341                 wfNumLink( $offset, 50, $title, $query ),
1342                 wfNumLink( $offset, 100, $title, $query ),
1343                 wfNumLink( $offset, 250, $title, $query ),
1344                 wfNumLink( $offset, 500, $title, $query )
1345         ) );
1346         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1347 }
1348
1349 /**
1350  * Generate links for (20|50|100...) items-per-page links
1351  *
1352  * @param $offset String
1353  * @param $limit Integer
1354  * @param $title Title
1355  * @param $query String: optional URL query parameter string
1356  */
1357 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1358         global $wgLang;
1359         if( $query == '' ) {
1360                 $q = '';
1361         } else {
1362                 $q = $query.'&';
1363         }
1364         $q .= "limit={$limit}&offset={$offset}";
1365         $fmtLimit = $wgLang->formatNum( $limit );
1366         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1367         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1368         return $s;
1369 }
1370
1371 /**
1372  * @todo document
1373  * @todo FIXME: We may want to blacklist some broken browsers
1374  *
1375  * @param $force Bool
1376  * @return bool Whereas client accept gzip compression
1377  */
1378 function wfClientAcceptsGzip( $force = false ) {
1379         static $result = null;
1380         if ( $result === null || $force ) {
1381                 $result = false;
1382                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1383                         # @todo FIXME: We may want to blacklist some broken browsers
1384                         $m = array();
1385                         if( preg_match(
1386                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1387                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1388                                 $m )
1389                         )
1390                         {
1391                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1392                                         $result = false;
1393                                         return $result;
1394                                 }
1395                                 wfDebug( " accepts gzip\n" );
1396                                 $result = true;
1397                         }
1398                 }
1399         }
1400         return $result;
1401 }
1402
1403 /**
1404  * Obtain the offset and limit values from the request string;
1405  * used in special pages
1406  *
1407  * @param $deflimit Int default limit if none supplied
1408  * @param $optionname String Name of a user preference to check against
1409  * @return array
1410  *
1411  */
1412 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1413         global $wgRequest;
1414         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1415 }
1416
1417 /**
1418  * Escapes the given text so that it may be output using addWikiText()
1419  * without any linking, formatting, etc. making its way through. This
1420  * is achieved by substituting certain characters with HTML entities.
1421  * As required by the callers, <nowiki> is not used.
1422  *
1423  * @param $text String: text to be escaped
1424  * @return String
1425  */
1426 function wfEscapeWikiText( $text ) {
1427         $text = strtr( "\n$text", array(
1428                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1429                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1430                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1431                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1432                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1433                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1434         ) );
1435         return substr( $text, 1 );
1436 }
1437
1438 /**
1439  * Get the current unix timetstamp with microseconds.  Useful for profiling
1440  * @return Float
1441  */
1442 function wfTime() {
1443         return microtime( true );
1444 }
1445
1446 /**
1447  * Sets dest to source and returns the original value of dest
1448  * If source is NULL, it just returns the value, it doesn't set the variable
1449  * If force is true, it will set the value even if source is NULL
1450  *
1451  * @param $dest Mixed
1452  * @param $source Mixed
1453  * @param $force Bool
1454  * @return Mixed
1455  */
1456 function wfSetVar( &$dest, $source, $force = false ) {
1457         $temp = $dest;
1458         if ( !is_null( $source ) || $force ) {
1459                 $dest = $source;
1460         }
1461         return $temp;
1462 }
1463
1464 /**
1465  * As for wfSetVar except setting a bit
1466  *
1467  * @param $dest Int
1468  * @param $bit Int
1469  * @param $state Bool
1470  */
1471 function wfSetBit( &$dest, $bit, $state = true ) {
1472         $temp = (bool)( $dest & $bit );
1473         if ( !is_null( $state ) ) {
1474                 if ( $state ) {
1475                         $dest |= $bit;
1476                 } else {
1477                         $dest &= ~$bit;
1478                 }
1479         }
1480         return $temp;
1481 }
1482
1483 /**
1484  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1485  * "days=7&limit=100". Options in the first array override options in the second.
1486  * Options set to "" will not be output.
1487  *
1488  * @param $array1 Array( String|Array )
1489  * @param $array2 Array( String|Array )
1490  * @return String
1491  */
1492 function wfArrayToCGI( $array1, $array2 = null ) {
1493         if ( !is_null( $array2 ) ) {
1494                 $array1 = $array1 + $array2;
1495         }
1496
1497         $cgi = '';
1498         foreach ( $array1 as $key => $value ) {
1499                 if ( $value !== '' ) {
1500                         if ( $cgi != '' ) {
1501                                 $cgi .= '&';
1502                         }
1503                         if ( is_array( $value ) ) {
1504                                 $firstTime = true;
1505                                 foreach ( $value as $v ) {
1506                                         $cgi .= ( $firstTime ? '' : '&') .
1507                                                 urlencode( $key . '[]' ) . '=' .
1508                                                 urlencode( $v );
1509                                         $firstTime = false;
1510                                 }
1511                         } else {
1512                                 if ( is_object( $value ) ) {
1513                                         $value = $value->__toString();
1514                                 }
1515                                 $cgi .= urlencode( $key ) . '=' .
1516                                         urlencode( $value );
1517                         }
1518                 }
1519         }
1520         return $cgi;
1521 }
1522
1523 /**
1524  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1525  * its argument and returns the same string in array form.  This allows compa-
1526  * tibility with legacy functions that accept raw query strings instead of nice
1527  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1528  * valid query strings, or it will explode.
1529  *
1530  * @param $query String: query string
1531  * @return array Array version of input
1532  */
1533 function wfCgiToArray( $query ) {
1534         if( isset( $query[0] ) && $query[0] == '?' ) {
1535                 $query = substr( $query, 1 );
1536         }
1537         $bits = explode( '&', $query );
1538         $ret = array();
1539         foreach( $bits as $bit ) {
1540                 if( $bit === '' ) {
1541                         continue;
1542                 }
1543                 list( $key, $value ) = explode( '=', $bit );
1544                 $key = urldecode( $key );
1545                 $value = urldecode( $value );
1546                 $ret[$key] = $value;
1547         }
1548         return $ret;
1549 }
1550
1551 /**
1552  * Append a query string to an existing URL, which may or may not already
1553  * have query string parameters already. If so, they will be combined.
1554  *
1555  * @param $url String
1556  * @param $query Mixed: string or associative array
1557  * @return string
1558  */
1559 function wfAppendQuery( $url, $query ) {
1560         if ( is_array( $query ) ) {
1561                 $query = wfArrayToCGI( $query );
1562         }
1563         if( $query != '' ) {
1564                 if( false === strpos( $url, '?' ) ) {
1565                         $url .= '?';
1566                 } else {
1567                         $url .= '&';
1568                 }
1569                 $url .= $query;
1570         }
1571         return $url;
1572 }
1573
1574 /**
1575  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1576  * is correct.
1577  *
1578  * @todo this won't work with current-path-relative URLs
1579  * like "subdir/foo.html", etc.
1580  *
1581  * @param $url String: either fully-qualified or a local path + query
1582  * @return string Fully-qualified URL
1583  */
1584 function wfExpandUrl( $url ) {
1585         global $wgServer;
1586         if( substr( $url, 0, 2 ) == '//' ) {
1587                 $bits = wfParseUrl( $wgServer );
1588                 $scheme = $bits ? $bits['scheme'] : 'http';
1589                 return $scheme . ':' . $url;
1590         } elseif( substr( $url, 0, 1 ) == '/' ) {
1591                 return $wgServer . $url;
1592         } else {
1593                 return $url;
1594         }
1595 }
1596
1597 /**
1598  * Windows-compatible version of escapeshellarg()
1599  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1600  * function puts single quotes in regardless of OS.
1601  *
1602  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1603  * earlier distro releases of PHP)
1604  *
1605  * @param varargs
1606  * @return String
1607  */
1608 function wfEscapeShellArg( ) {
1609         wfInitShellLocale();
1610
1611         $args = func_get_args();
1612         $first = true;
1613         $retVal = '';
1614         foreach ( $args as $arg ) {
1615                 if ( !$first ) {
1616                         $retVal .= ' ';
1617                 } else {
1618                         $first = false;
1619                 }
1620
1621                 if ( wfIsWindows() ) {
1622                         // Escaping for an MSVC-style command line parser and CMD.EXE
1623                         // Refs:
1624                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1625                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1626                         //  * Bug #13518
1627                         //  * CR r63214
1628                         // Double the backslashes before any double quotes. Escape the double quotes.
1629                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1630                         $arg = '';
1631                         $iteration = 0;
1632                         foreach ( $tokens as $token ) {
1633                                 if ( $iteration % 2 == 1 ) {
1634                                         // Delimiter, a double quote preceded by zero or more slashes
1635                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1636                                 } elseif ( $iteration % 4 == 2 ) {
1637                                         // ^ in $token will be outside quotes, need to be escaped
1638                                         $arg .= str_replace( '^', '^^', $token );
1639                                 } else { // $iteration % 4 == 0
1640                                         // ^ in $token will appear inside double quotes, so leave as is
1641                                         $arg .= $token;
1642                                 }
1643                                 $iteration++;
1644                         }
1645                         // Double the backslashes before the end of the string, because
1646                         // we will soon add a quote
1647                         $m = array();
1648                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1649                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1650                         }
1651
1652                         // Add surrounding quotes
1653                         $retVal .= '"' . $arg . '"';
1654                 } else {
1655                         $retVal .= escapeshellarg( $arg );
1656                 }
1657         }
1658         return $retVal;
1659 }
1660
1661 /**
1662  * wfMerge attempts to merge differences between three texts.
1663  * Returns true for a clean merge and false for failure or a conflict.
1664  *
1665  * @param $old String
1666  * @param $mine String
1667  * @param $yours String
1668  * @param $result String
1669  * @return Bool
1670  */
1671 function wfMerge( $old, $mine, $yours, &$result ) {
1672         global $wgDiff3;
1673
1674         # This check may also protect against code injection in
1675         # case of broken installations.
1676         wfSuppressWarnings();
1677         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1678         wfRestoreWarnings();
1679
1680         if( !$haveDiff3 ) {
1681                 wfDebug( "diff3 not found\n" );
1682                 return false;
1683         }
1684
1685         # Make temporary files
1686         $td = wfTempDir();
1687         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1688         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1689         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1690
1691         fwrite( $oldtextFile, $old );
1692         fclose( $oldtextFile );
1693         fwrite( $mytextFile, $mine );
1694         fclose( $mytextFile );
1695         fwrite( $yourtextFile, $yours );
1696         fclose( $yourtextFile );
1697
1698         # Check for a conflict
1699         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1700                 wfEscapeShellArg( $mytextName ) . ' ' .
1701                 wfEscapeShellArg( $oldtextName ) . ' ' .
1702                 wfEscapeShellArg( $yourtextName );
1703         $handle = popen( $cmd, 'r' );
1704
1705         if( fgets( $handle, 1024 ) ) {
1706                 $conflict = true;
1707         } else {
1708                 $conflict = false;
1709         }
1710         pclose( $handle );
1711
1712         # Merge differences
1713         $cmd = $wgDiff3 . ' -a -e --merge ' .
1714                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1715         $handle = popen( $cmd, 'r' );
1716         $result = '';
1717         do {
1718                 $data = fread( $handle, 8192 );
1719                 if ( strlen( $data ) == 0 ) {
1720                         break;
1721                 }
1722                 $result .= $data;
1723         } while ( true );
1724         pclose( $handle );
1725         unlink( $mytextName );
1726         unlink( $oldtextName );
1727         unlink( $yourtextName );
1728
1729         if ( $result === '' && $old !== '' && !$conflict ) {
1730                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1731                 $conflict = true;
1732         }
1733         return !$conflict;
1734 }
1735
1736 /**
1737  * Returns unified plain-text diff of two texts.
1738  * Useful for machine processing of diffs.
1739  *
1740  * @param $before String: the text before the changes.
1741  * @param $after String: the text after the changes.
1742  * @param $params String: command-line options for the diff command.
1743  * @return String: unified diff of $before and $after
1744  */
1745 function wfDiff( $before, $after, $params = '-u' ) {
1746         if ( $before == $after ) {
1747                 return '';
1748         }
1749
1750         global $wgDiff;
1751         wfSuppressWarnings();
1752         $haveDiff = $wgDiff && file_exists( $wgDiff );
1753         wfRestoreWarnings();
1754
1755         # This check may also protect against code injection in
1756         # case of broken installations.
1757         if( !$haveDiff ) {
1758                 wfDebug( "diff executable not found\n" );
1759                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1760                 $format = new UnifiedDiffFormatter();
1761                 return $format->format( $diffs );
1762         }
1763
1764         # Make temporary files
1765         $td = wfTempDir();
1766         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1767         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1768
1769         fwrite( $oldtextFile, $before );
1770         fclose( $oldtextFile );
1771         fwrite( $newtextFile, $after );
1772         fclose( $newtextFile );
1773
1774         // Get the diff of the two files
1775         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1776
1777         $h = popen( $cmd, 'r' );
1778
1779         $diff = '';
1780
1781         do {
1782                 $data = fread( $h, 8192 );
1783                 if ( strlen( $data ) == 0 ) {
1784                         break;
1785                 }
1786                 $diff .= $data;
1787         } while ( true );
1788
1789         // Clean up
1790         pclose( $h );
1791         unlink( $oldtextName );
1792         unlink( $newtextName );
1793
1794         // Kill the --- and +++ lines. They're not useful.
1795         $diff_lines = explode( "\n", $diff );
1796         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1797                 unset( $diff_lines[0] );
1798         }
1799         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1800                 unset( $diff_lines[1] );
1801         }
1802
1803         $diff = implode( "\n", $diff_lines );
1804
1805         return $diff;
1806 }
1807
1808 /**
1809  * A wrapper around the PHP function var_export().
1810  * Either print it or add it to the regular output ($wgOut).
1811  *
1812  * @param $var A PHP variable to dump.
1813  */
1814 function wfVarDump( $var ) {
1815         global $wgOut;
1816         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1817         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1818                 print $s;
1819         } else {
1820                 $wgOut->addHTML( $s );
1821         }
1822 }
1823
1824 /**
1825  * Provide a simple HTTP error.
1826  *
1827  * @param $code Int|String
1828  * @param $label String
1829  * @param $desc String
1830  */
1831 function wfHttpError( $code, $label, $desc ) {
1832         global $wgOut;
1833         $wgOut->disable();
1834         header( "HTTP/1.0 $code $label" );
1835         header( "Status: $code $label" );
1836         $wgOut->sendCacheControl();
1837
1838         header( 'Content-type: text/html; charset=utf-8' );
1839         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1840                 '<html><head><title>' .
1841                 htmlspecialchars( $label ) .
1842                 '</title></head><body><h1>' .
1843                 htmlspecialchars( $label ) .
1844                 '</h1><p>' .
1845                 nl2br( htmlspecialchars( $desc ) ) .
1846                 "</p></body></html>\n";
1847 }
1848
1849 /**
1850  * Clear away any user-level output buffers, discarding contents.
1851  *
1852  * Suitable for 'starting afresh', for instance when streaming
1853  * relatively large amounts of data without buffering, or wanting to
1854  * output image files without ob_gzhandler's compression.
1855  *
1856  * The optional $resetGzipEncoding parameter controls suppression of
1857  * the Content-Encoding header sent by ob_gzhandler; by default it
1858  * is left. See comments for wfClearOutputBuffers() for why it would
1859  * be used.
1860  *
1861  * Note that some PHP configuration options may add output buffer
1862  * layers which cannot be removed; these are left in place.
1863  *
1864  * @param $resetGzipEncoding Bool
1865  */
1866 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1867         if( $resetGzipEncoding ) {
1868                 // Suppress Content-Encoding and Content-Length
1869                 // headers from 1.10+s wfOutputHandler
1870                 global $wgDisableOutputCompression;
1871                 $wgDisableOutputCompression = true;
1872         }
1873         while( $status = ob_get_status() ) {
1874                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1875                         // Probably from zlib.output_compression or other
1876                         // PHP-internal setting which can't be removed.
1877                         //
1878                         // Give up, and hope the result doesn't break
1879                         // output behavior.
1880                         break;
1881                 }
1882                 if( !ob_end_clean() ) {
1883                         // Could not remove output buffer handler; abort now
1884                         // to avoid getting in some kind of infinite loop.
1885                         break;
1886                 }
1887                 if( $resetGzipEncoding ) {
1888                         if( $status['name'] == 'ob_gzhandler' ) {
1889                                 // Reset the 'Content-Encoding' field set by this handler
1890                                 // so we can start fresh.
1891                                 if ( function_exists( 'header_remove' ) ) {
1892                                         // Available since PHP 5.3.0
1893                                         header_remove( 'Content-Encoding' );
1894                                 } else {
1895                                         // We need to provide a valid content-coding. See bug 28069
1896                                         header( 'Content-Encoding: identity' );
1897                                 }
1898                                 break;
1899                         }
1900                 }
1901         }
1902 }
1903
1904 /**
1905  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1906  *
1907  * Clear away output buffers, but keep the Content-Encoding header
1908  * produced by ob_gzhandler, if any.
1909  *
1910  * This should be used for HTTP 304 responses, where you need to
1911  * preserve the Content-Encoding header of the real result, but
1912  * also need to suppress the output of ob_gzhandler to keep to spec
1913  * and avoid breaking Firefox in rare cases where the headers and
1914  * body are broken over two packets.
1915  */
1916 function wfClearOutputBuffers() {
1917         wfResetOutputBuffers( false );
1918 }
1919
1920 /**
1921  * Converts an Accept-* header into an array mapping string values to quality
1922  * factors
1923  *
1924  * @param $accept String
1925  * @param $def String default
1926  * @return Array
1927  */
1928 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1929         # No arg means accept anything (per HTTP spec)
1930         if( !$accept ) {
1931                 return array( $def => 1.0 );
1932         }
1933
1934         $prefs = array();
1935
1936         $parts = explode( ',', $accept );
1937
1938         foreach( $parts as $part ) {
1939                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1940                 $values = explode( ';', trim( $part ) );
1941                 $match = array();
1942                 if ( count( $values ) == 1 ) {
1943                         $prefs[$values[0]] = 1.0;
1944                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1945                         $prefs[$values[0]] = floatval( $match[1] );
1946                 }
1947         }
1948
1949         return $prefs;
1950 }
1951
1952 /**
1953  * Checks if a given MIME type matches any of the keys in the given
1954  * array. Basic wildcards are accepted in the array keys.
1955  *
1956  * Returns the matching MIME type (or wildcard) if a match, otherwise
1957  * NULL if no match.
1958  *
1959  * @param $type String
1960  * @param $avail Array
1961  * @return string
1962  * @private
1963  */
1964 function mimeTypeMatch( $type, $avail ) {
1965         if( array_key_exists( $type, $avail ) ) {
1966                 return $type;
1967         } else {
1968                 $parts = explode( '/', $type );
1969                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1970                         return $parts[0] . '/*';
1971                 } elseif( array_key_exists( '*/*', $avail ) ) {
1972                         return '*/*';
1973                 } else {
1974                         return null;
1975                 }
1976         }
1977 }
1978
1979 /**
1980  * Returns the 'best' match between a client's requested internet media types
1981  * and the server's list of available types. Each list should be an associative
1982  * array of type to preference (preference is a float between 0.0 and 1.0).
1983  * Wildcards in the types are acceptable.
1984  *
1985  * @param $cprefs Array: client's acceptable type list
1986  * @param $sprefs Array: server's offered types
1987  * @return string
1988  *
1989  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1990  * XXX: generalize to negotiate other stuff
1991  */
1992 function wfNegotiateType( $cprefs, $sprefs ) {
1993         $combine = array();
1994
1995         foreach( array_keys($sprefs) as $type ) {
1996                 $parts = explode( '/', $type );
1997                 if( $parts[1] != '*' ) {
1998                         $ckey = mimeTypeMatch( $type, $cprefs );
1999                         if( $ckey ) {
2000                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2001                         }
2002                 }
2003         }
2004
2005         foreach( array_keys( $cprefs ) as $type ) {
2006                 $parts = explode( '/', $type );
2007                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2008                         $skey = mimeTypeMatch( $type, $sprefs );
2009                         if( $skey ) {
2010                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2011                         }
2012                 }
2013         }
2014
2015         $bestq = 0;
2016         $besttype = null;
2017
2018         foreach( array_keys( $combine ) as $type ) {
2019                 if( $combine[$type] > $bestq ) {
2020                         $besttype = $type;
2021                         $bestq = $combine[$type];
2022                 }
2023         }
2024
2025         return $besttype;
2026 }
2027
2028 /**
2029  * Reference-counted warning suppression
2030  *
2031  * @param $end Bool
2032  */
2033 function wfSuppressWarnings( $end = false ) {
2034         static $suppressCount = 0;
2035         static $originalLevel = false;
2036
2037         if ( $end ) {
2038                 if ( $suppressCount ) {
2039                         --$suppressCount;
2040                         if ( !$suppressCount ) {
2041                                 error_reporting( $originalLevel );
2042                         }
2043                 }
2044         } else {
2045                 if ( !$suppressCount ) {
2046                         // E_DEPRECATED is undefined in PHP 5.2
2047                         if( !defined( 'E_DEPRECATED' ) ){
2048                                 define( 'E_DEPRECATED', 8192 );
2049                         }
2050                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2051                 }
2052                 ++$suppressCount;
2053         }
2054 }
2055
2056 /**
2057  * Restore error level to previous value
2058  */
2059 function wfRestoreWarnings() {
2060         wfSuppressWarnings( true );
2061 }
2062
2063 # Autodetect, convert and provide timestamps of various types
2064
2065 /**
2066  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2067  */
2068 define( 'TS_UNIX', 0 );
2069
2070 /**
2071  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2072  */
2073 define( 'TS_MW', 1 );
2074
2075 /**
2076  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2077  */
2078 define( 'TS_DB', 2 );
2079
2080 /**
2081  * RFC 2822 format, for E-mail and HTTP headers
2082  */
2083 define( 'TS_RFC2822', 3 );
2084
2085 /**
2086  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2087  *
2088  * This is used by Special:Export
2089  */
2090 define( 'TS_ISO_8601', 4 );
2091
2092 /**
2093  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2094  *
2095  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2096  *       DateTime tag and page 36 for the DateTimeOriginal and
2097  *       DateTimeDigitized tags.
2098  */
2099 define( 'TS_EXIF', 5 );
2100
2101 /**
2102  * Oracle format time.
2103  */
2104 define( 'TS_ORACLE', 6 );
2105
2106 /**
2107  * Postgres format time.
2108  */
2109 define( 'TS_POSTGRES', 7 );
2110
2111 /**
2112  * DB2 format time
2113  */
2114 define( 'TS_DB2', 8 );
2115
2116 /**
2117  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2118  */
2119 define( 'TS_ISO_8601_BASIC', 9 );
2120
2121 /**
2122  * Get a timestamp string in one of various formats
2123  *
2124  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2125  *                    function will autodetect which format is supplied and act
2126  *                    accordingly.
2127  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2128  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2129  */
2130 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2131         $uts = 0;
2132         $da = array();
2133         $strtime = '';
2134
2135         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2136                 $uts = time();
2137                 $strtime = "@$uts";
2138         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2139                 # TS_DB
2140         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2141                 # TS_EXIF
2142         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2143                 # TS_MW
2144         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2145                 # TS_UNIX
2146                 $uts = $ts;
2147                 $strtime = "@$ts"; // Undocumented?
2148         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2149                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2150                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2151                                 str_replace( '+00:00', 'UTC', $ts ) );
2152         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2153                 # TS_ISO_8601
2154         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2155                 #TS_ISO_8601_BASIC
2156         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2157                 # TS_POSTGRES
2158         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2159                 # TS_POSTGRES
2160         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2161                 # TS_DB2
2162         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2163                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2164                                                         '[ \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
2165                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2166                 # The regex is a superset of rfc2822 for readability
2167                 $strtime = strtok( $ts, ';' );
2168         } 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 ) ) {
2169                 # TS_RFC850
2170                 $strtime = $ts;
2171         } 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 ) ) {
2172                 # asctime
2173                 $strtime = $ts;
2174         } else {
2175                 # Bogus value...
2176                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2177
2178                 return false;
2179         }
2180
2181         static $formats = array(
2182                 TS_UNIX => 'U',
2183                 TS_MW => 'YmdHis',
2184                 TS_DB => 'Y-m-d H:i:s',
2185                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2186                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2187                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2188                 TS_RFC2822 => 'D, d M Y H:i:s',
2189                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2190                 TS_POSTGRES => 'Y-m-d H:i:s',
2191                 TS_DB2 => 'Y-m-d H:i:s',
2192         );
2193
2194         if ( !isset( $formats[$outputtype] ) ) {
2195                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2196         }
2197
2198         if ( function_exists( "date_create" ) ) {
2199                 if ( count( $da ) ) {
2200                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2201                                 (int)$da[1], (int)$da[2], (int)$da[3],
2202                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2203
2204                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2205                 } elseif ( $strtime ) {
2206                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2207                 } else {
2208                         return false;
2209                 }
2210
2211                 if ( !$d ) {
2212                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2213                         return false;
2214                 }
2215
2216                 $output = $d->format( $formats[$outputtype] );
2217         } else {
2218                 if ( count( $da ) ) {
2219                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2220                         // We may want to handle that explicitly at some point
2221                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2222                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2223                 } elseif ( $strtime ) {
2224                         $uts = strtotime( $strtime );
2225                 }
2226
2227                 if ( $uts === false ) {
2228                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2229                         return false;
2230                 }
2231
2232                 if ( TS_UNIX == $outputtype ) {
2233                         return $uts;
2234                 }
2235                 $output = gmdate( $formats[$outputtype], $uts );
2236         }
2237
2238         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2239                 $output .= ' GMT';
2240         }
2241
2242         return $output;
2243 }
2244
2245 /**
2246  * Return a formatted timestamp, or null if input is null.
2247  * For dealing with nullable timestamp columns in the database.
2248  *
2249  * @param $outputtype Integer
2250  * @param $ts String
2251  * @return String
2252  */
2253 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2254         if( is_null( $ts ) ) {
2255                 return null;
2256         } else {
2257                 return wfTimestamp( $outputtype, $ts );
2258         }
2259 }
2260
2261 /**
2262  * Convenience function; returns MediaWiki timestamp for the present time.
2263  *
2264  * @return string
2265  */
2266 function wfTimestampNow() {
2267         # return NOW
2268         return wfTimestamp( TS_MW, time() );
2269 }
2270
2271 /**
2272  * Check if the operating system is Windows
2273  *
2274  * @return Bool: true if it's Windows, False otherwise.
2275  */
2276 function wfIsWindows() {
2277         static $isWindows = null;
2278         if ( $isWindows === null ) {
2279                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2280         }
2281         return $isWindows;
2282 }
2283
2284 /**
2285  * Check if we are running under HipHop
2286  *
2287  * @return Bool
2288  */
2289 function wfIsHipHop() {
2290         return function_exists( 'hphp_thread_set_warmup_enabled' );
2291 }
2292
2293 /**
2294  * Swap two variables
2295  *
2296  * @param $x Mixed
2297  * @param $y Mixed
2298  */
2299 function swap( &$x, &$y ) {
2300         $z = $x;
2301         $x = $y;
2302         $y = $z;
2303 }
2304
2305 /**
2306  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2307  * TEMP environment variables are then checked in sequence, and if none are set
2308  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2309  * or C:\Windows\Temp for Windows and hope for the best.
2310  * It is common to call it with tempnam().
2311  *
2312  * NOTE: When possible, use instead the tmpfile() function to create
2313  * temporary files to avoid race conditions on file creation, etc.
2314  *
2315  * @return String
2316  */
2317 function wfTempDir() {
2318         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2319                 $tmp = getenv( $var );
2320                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2321                         return $tmp;
2322                 }
2323         }
2324         if( function_exists( 'sys_get_temp_dir' ) ) {
2325                 return sys_get_temp_dir();
2326         }
2327         # Usual defaults
2328         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2329 }
2330
2331 /**
2332  * Make directory, and make all parent directories if they don't exist
2333  *
2334  * @param $dir String: full path to directory to create
2335  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2336  * @param $caller String: optional caller param for debugging.
2337  * @return bool
2338  */
2339 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2340         global $wgDirectoryMode;
2341
2342         if ( !is_null( $caller ) ) {
2343                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2344         }
2345
2346         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2347                 return true;
2348         }
2349
2350         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2351
2352         if ( is_null( $mode ) ) {
2353                 $mode = $wgDirectoryMode;
2354         }
2355
2356         // Turn off the normal warning, we're doing our own below
2357         wfSuppressWarnings();
2358         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2359         wfRestoreWarnings();
2360
2361         if( !$ok ) {
2362                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2363                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2364         }
2365         return $ok;
2366 }
2367
2368 /**
2369  * Increment a statistics counter
2370  *
2371  * @param $key String
2372  * @param $count Int
2373  */
2374 function wfIncrStats( $key, $count = 1 ) {
2375         global $wgStatsMethod;
2376
2377         $count = intval( $count );
2378
2379         if( $wgStatsMethod == 'udp' ) {
2380                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2381                 static $socket;
2382
2383                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2384
2385                 if ( !$socket ) {
2386                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2387                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2388                         socket_sendto(
2389                                 $socket,
2390                                 $statline,
2391                                 strlen( $statline ),
2392                                 0,
2393                                 $wgUDPProfilerHost,
2394                                 $wgUDPProfilerPort
2395                         );
2396                 }
2397                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2398                 wfSuppressWarnings();
2399                 socket_sendto(
2400                         $socket,
2401                         $statline,
2402                         strlen( $statline ),
2403                         0,
2404                         $wgUDPProfilerHost,
2405                         $wgUDPProfilerPort
2406                 );
2407                 wfRestoreWarnings();
2408         } elseif( $wgStatsMethod == 'cache' ) {
2409                 global $wgMemc;
2410                 $key = wfMemcKey( 'stats', $key );
2411                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2412                         $wgMemc->add( $key, $count );
2413                 }
2414         } else {
2415                 // Disabled
2416         }
2417 }
2418
2419 /**
2420  * @param $nr Mixed: the number to format
2421  * @param $acc Integer: the number of digits after the decimal point, default 2
2422  * @param $round Boolean: whether or not to round the value, default true
2423  * @return float
2424  */
2425 function wfPercent( $nr, $acc = 2, $round = true ) {
2426         $ret = sprintf( "%.${acc}f", $nr );
2427         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2428 }
2429
2430 /**
2431  * Find out whether or not a mixed variable exists in a string
2432  *
2433  * @param $needle String
2434  * @param $str String
2435  * @param $insensitive Boolean
2436  * @return Boolean
2437  */
2438 function in_string( $needle, $str, $insensitive = false ) {
2439         $func = 'strpos';
2440         if( $insensitive ) $func = 'stripos';
2441
2442         return $func( $str, $needle ) !== false;
2443 }
2444
2445 function wfSpecialList( $page, $details ) {
2446         global $wgContLang;
2447         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2448         return $page . $details;
2449 }
2450
2451 /**
2452  * Returns a regular expression of url protocols
2453  *
2454  * @return String
2455  */
2456 function wfUrlProtocols() {
2457         global $wgUrlProtocols;
2458
2459         static $retval = null;
2460         if ( !is_null( $retval ) ) {
2461                 return $retval;
2462         }
2463
2464         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2465         // with LocalSettings files from 1.5
2466         if ( is_array( $wgUrlProtocols ) ) {
2467                 $protocols = array();
2468                 foreach ( $wgUrlProtocols as $protocol ) {
2469                         $protocols[] = preg_quote( $protocol, '/' );
2470                 }
2471
2472                 $retval = implode( '|', $protocols );
2473         } else {
2474                 $retval = $wgUrlProtocols;
2475         }
2476         return $retval;
2477 }
2478
2479 /**
2480  * Safety wrapper around ini_get() for boolean settings.
2481  * The values returned from ini_get() are pre-normalized for settings
2482  * set via php.ini or php_flag/php_admin_flag... but *not*
2483  * for those set via php_value/php_admin_value.
2484  *
2485  * It's fairly common for people to use php_value instead of php_flag,
2486  * which can leave you with an 'off' setting giving a false positive
2487  * for code that just takes the ini_get() return value as a boolean.
2488  *
2489  * To make things extra interesting, setting via php_value accepts
2490  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2491  * Unrecognized values go false... again opposite PHP's own coercion
2492  * from string to bool.
2493  *
2494  * Luckily, 'properly' set settings will always come back as '0' or '1',
2495  * so we only have to worry about them and the 'improper' settings.
2496  *
2497  * I frickin' hate PHP... :P
2498  *
2499  * @param $setting String
2500  * @return Bool
2501  */
2502 function wfIniGetBool( $setting ) {
2503         $val = ini_get( $setting );
2504         // 'on' and 'true' can't have whitespace around them, but '1' can.
2505         return strtolower( $val ) == 'on'
2506                 || strtolower( $val ) == 'true'
2507                 || strtolower( $val ) == 'yes'
2508                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2509 }
2510
2511 /**
2512  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2513  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2514  *
2515  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2516  *                          should be omitted
2517  * @param $fileName String Name of the library, if not $extension.suffix
2518  * @return Bool - Whether or not the extension is loaded
2519  */
2520 function wfDl( $extension, $fileName = null ) {
2521         if( extension_loaded( $extension ) ) {
2522                 return true;
2523         }
2524
2525         $canDl = false;
2526         $sapi = php_sapi_name();
2527         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2528                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2529         {
2530                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2531                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2532         }
2533
2534         if( $canDl ) {
2535                 $fileName = $fileName ? $fileName : $extension;
2536                 if( wfIsWindows() ) {
2537                         $fileName = 'php_' . $fileName;
2538                 }
2539                 wfSuppressWarnings();
2540                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2541                 wfRestoreWarnings();
2542         }
2543         return extension_loaded( $extension );
2544 }
2545
2546 /**
2547  * Execute a shell command, with time and memory limits mirrored from the PHP
2548  * configuration if supported.
2549  * @param $cmd String Command line, properly escaped for shell.
2550  * @param &$retval optional, will receive the program's exit code.
2551  *                 (non-zero is usually failure)
2552  * @param $environ Array optional environment variables which should be
2553  *                 added to the executed command environment.
2554  * @return collected stdout as a string (trailing newlines stripped)
2555  */
2556 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2557         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2558
2559         static $disabled;
2560         if ( is_null( $disabled ) ) {
2561                 $disabled = false;
2562                 if( wfIniGetBool( 'safe_mode' ) ) {
2563                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2564                         $disabled = 'safemode';
2565                 } else {
2566                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2567                         $functions = array_map( 'trim', $functions );
2568                         $functions = array_map( 'strtolower', $functions );
2569                         if ( in_array( 'passthru', $functions ) ) {
2570                                 wfDebug( "passthru is in disabled_functions\n" );
2571                                 $disabled = 'passthru';
2572                         }
2573                 }
2574         }
2575         if ( $disabled ) {
2576                 $retval = 1;
2577                 return $disabled == 'safemode' ?
2578                         'Unable to run external programs in safe mode.' :
2579                         'Unable to run external programs, passthru() is disabled.';
2580         }
2581
2582         wfInitShellLocale();
2583
2584         $envcmd = '';
2585         foreach( $environ as $k => $v ) {
2586                 if ( wfIsWindows() ) {
2587                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2588                          * appear in the environment variable, so we must use carat escaping as documented in
2589                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2590                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2591                          * are listed there but doesn't appear to need it.
2592                          */
2593                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2594                 } else {
2595                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2596                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2597                          */
2598                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2599                 }
2600         }
2601         $cmd = $envcmd . $cmd;
2602
2603         if ( wfIsWindows() ) {
2604                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2605                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2606                 {
2607                         # Hack to work around PHP's flawed invocation of cmd.exe
2608                         # http://news.php.net/php.internals/21796
2609                         # Windows 9x doesn't accept any kind of quotes
2610                         $cmd = '"' . $cmd . '"';
2611                 }
2612         } elseif ( php_uname( 's' ) == 'Linux' ) {
2613                 $time = intval( $wgMaxShellTime );
2614                 $mem = intval( $wgMaxShellMemory );
2615                 $filesize = intval( $wgMaxShellFileSize );
2616
2617                 if ( $time > 0 && $mem > 0 ) {
2618                         $script = "$IP/bin/ulimit4.sh";
2619                         if ( is_executable( $script ) ) {
2620                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2621                         }
2622                 }
2623         }
2624         wfDebug( "wfShellExec: $cmd\n" );
2625
2626         $retval = 1; // error by default?
2627         ob_start();
2628         passthru( $cmd, $retval );
2629         $output = ob_get_contents();
2630         ob_end_clean();
2631
2632         if ( $retval == 127 ) {
2633                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2634         }
2635         return $output;
2636 }
2637
2638 /**
2639  * Workaround for http://bugs.php.net/bug.php?id=45132
2640  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2641  */
2642 function wfInitShellLocale() {
2643         static $done = false;
2644         if ( $done ) {
2645                 return;
2646         }
2647         $done = true;
2648         global $wgShellLocale;
2649         if ( !wfIniGetBool( 'safe_mode' ) ) {
2650                 putenv( "LC_CTYPE=$wgShellLocale" );
2651                 setlocale( LC_CTYPE, $wgShellLocale );
2652         }
2653 }
2654
2655 /**
2656  * This function works like "use VERSION" in Perl, the program will die with a
2657  * backtrace if the current version of PHP is less than the version provided
2658  *
2659  * This is useful for extensions which due to their nature are not kept in sync
2660  * with releases, and might depend on other versions of PHP than the main code
2661  *
2662  * Note: PHP might die due to parsing errors in some cases before it ever
2663  *       manages to call this function, such is life
2664  *
2665  * @see perldoc -f use
2666  *
2667  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2668  *                 a float
2669  */
2670 function wfUsePHP( $req_ver ) {
2671         $php_ver = PHP_VERSION;
2672
2673         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2674                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2675         }
2676 }
2677
2678 /**
2679  * This function works like "use VERSION" in Perl except it checks the version
2680  * of MediaWiki, the program will die with a backtrace if the current version
2681  * of MediaWiki is less than the version provided.
2682  *
2683  * This is useful for extensions which due to their nature are not kept in sync
2684  * with releases
2685  *
2686  * @see perldoc -f use
2687  *
2688  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2689  *                 a float
2690  */
2691 function wfUseMW( $req_ver ) {
2692         global $wgVersion;
2693
2694         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2695                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2696         }
2697 }
2698
2699 /**
2700  * Return the final portion of a pathname.
2701  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2702  * http://bugs.php.net/bug.php?id=33898
2703  *
2704  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2705  * We'll consider it so always, as we don't want \s in our Unix paths either.
2706  *
2707  * @param $path String
2708  * @param $suffix String: to remove if present
2709  * @return String
2710  */
2711 function wfBaseName( $path, $suffix = '' ) {
2712         $encSuffix = ( $suffix == '' )
2713                 ? ''
2714                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2715         $matches = array();
2716         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2717                 return $matches[1];
2718         } else {
2719                 return '';
2720         }
2721 }
2722
2723 /**
2724  * Generate a relative path name to the given file.
2725  * May explode on non-matching case-insensitive paths,
2726  * funky symlinks, etc.
2727  *
2728  * @param $path String: absolute destination path including target filename
2729  * @param $from String: Absolute source path, directory only
2730  * @return String
2731  */
2732 function wfRelativePath( $path, $from ) {
2733         // Normalize mixed input on Windows...
2734         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2735         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2736
2737         // Trim trailing slashes -- fix for drive root
2738         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2739         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2740
2741         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2742         $against = explode( DIRECTORY_SEPARATOR, $from );
2743
2744         if( $pieces[0] !== $against[0] ) {
2745                 // Non-matching Windows drive letters?
2746                 // Return a full path.
2747                 return $path;
2748         }
2749
2750         // Trim off common prefix
2751         while( count( $pieces ) && count( $against )
2752                 && $pieces[0] == $against[0] ) {
2753                 array_shift( $pieces );
2754                 array_shift( $against );
2755         }
2756
2757         // relative dots to bump us to the parent
2758         while( count( $against ) ) {
2759                 array_unshift( $pieces, '..' );
2760                 array_shift( $against );
2761         }
2762
2763         array_push( $pieces, wfBaseName( $path ) );
2764
2765         return implode( DIRECTORY_SEPARATOR, $pieces );
2766 }
2767
2768 /**
2769  * parse_url() work-alike, but non-broken.  Differences:
2770  *
2771  * 1) Does not raise warnings on bad URLs (just returns false)
2772  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2773  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2774  *
2775  * @param $url String: a URL to parse
2776  * @return Array: bits of the URL in an associative array, per PHP docs
2777  */
2778 function wfParseUrl( $url ) {
2779         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2780         wfSuppressWarnings();
2781         $bits = parse_url( $url );
2782         wfRestoreWarnings();
2783         if ( !$bits ) {
2784                 return false;
2785         }
2786
2787         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2788         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2789                 $bits['delimiter'] = '://';
2790         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2791                 $bits['delimiter'] = ':';
2792                 // parse_url detects for news: and mailto: the host part of an url as path
2793                 // We have to correct this wrong detection
2794                 if ( isset( $bits['path'] ) ) {
2795                         $bits['host'] = $bits['path'];
2796                         $bits['path'] = '';
2797                 }
2798         } else {
2799                 return false;
2800         }
2801
2802         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
2803         if ( !isset( $bits['host'] ) ) {
2804                 $bits['host'] = '';
2805
2806                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
2807                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
2808                         $bits['path'] = '/' . $bits['path'];
2809                 }
2810         }
2811         return $bits;
2812 }
2813
2814 /**
2815  * Make a URL index, appropriate for the el_index field of externallinks.
2816  *
2817  * @param $url String
2818  * @return String
2819  */
2820 function wfMakeUrlIndex( $url ) {
2821         $bits = wfParseUrl( $url );
2822
2823         // Reverse the labels in the hostname, convert to lower case
2824         // For emails reverse domainpart only
2825         if ( $bits['scheme'] == 'mailto' ) {
2826                 $mailparts = explode( '@', $bits['host'], 2 );
2827                 if ( count( $mailparts ) === 2 ) {
2828                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2829                 } else {
2830                         // No domain specified, don't mangle it
2831                         $domainpart = '';
2832                 }
2833                 $reversedHost = $domainpart . '@' . $mailparts[0];
2834         } else {
2835                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2836         }
2837         // Add an extra dot to the end
2838         // Why? Is it in wrong place in mailto links?
2839         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2840                 $reversedHost .= '.';
2841         }
2842         // Reconstruct the pseudo-URL
2843         $prot = $bits['scheme'];
2844         $index = $prot . $bits['delimiter'] . $reversedHost;
2845         // Leave out user and password. Add the port, path, query and fragment
2846         if ( isset( $bits['port'] ) ) {
2847                 $index .= ':' . $bits['port'];
2848         }
2849         if ( isset( $bits['path'] ) ) {
2850                 $index .= $bits['path'];
2851         } else {
2852                 $index .= '/';
2853         }
2854         if ( isset( $bits['query'] ) ) {
2855                 $index .= '?' . $bits['query'];
2856         }
2857         if ( isset( $bits['fragment'] ) ) {
2858                 $index .= '#' . $bits['fragment'];
2859         }
2860         return $index;
2861 }
2862
2863 /**
2864  * Do any deferred updates and clear the list
2865  *
2866  * @param $commit String: set to 'commit' to commit after every update to
2867  *                prevent lock contention
2868  */
2869 function wfDoUpdates( $commit = '' ) {
2870         global $wgDeferredUpdateList;
2871
2872         wfProfileIn( __METHOD__ );
2873
2874         // No need to get master connections in case of empty updates array
2875         if ( !count( $wgDeferredUpdateList ) ) {
2876                 wfProfileOut( __METHOD__ );
2877                 return;
2878         }
2879
2880         $doCommit = $commit == 'commit';
2881         if ( $doCommit ) {
2882                 $dbw = wfGetDB( DB_MASTER );
2883         }
2884
2885         foreach ( $wgDeferredUpdateList as $update ) {
2886                 $update->doUpdate();
2887
2888                 if ( $doCommit && $dbw->trxLevel() ) {
2889                         $dbw->commit();
2890                 }
2891         }
2892
2893         $wgDeferredUpdateList = array();
2894         wfProfileOut( __METHOD__ );
2895 }
2896
2897 /**
2898  * Convert an arbitrarily-long digit string from one numeric base
2899  * to another, optionally zero-padding to a minimum column width.
2900  *
2901  * Supports base 2 through 36; digit values 10-36 are represented
2902  * as lowercase letters a-z. Input is case-insensitive.
2903  *
2904  * @param $input String: of digits
2905  * @param $sourceBase Integer: 2-36
2906  * @param $destBase Integer: 2-36
2907  * @param $pad Integer: 1 or greater
2908  * @param $lowercase Boolean
2909  * @return String or false on invalid input
2910  */
2911 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2912         $input = strval( $input );
2913         if( $sourceBase < 2 ||
2914                 $sourceBase > 36 ||
2915                 $destBase < 2 ||
2916                 $destBase > 36 ||
2917                 $pad < 1 ||
2918                 $sourceBase != intval( $sourceBase ) ||
2919                 $destBase != intval( $destBase ) ||
2920                 $pad != intval( $pad ) ||
2921                 !is_string( $input ) ||
2922                 $input == '' ) {
2923                 return false;
2924         }
2925         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2926         $inDigits = array();
2927         $outChars = '';
2928
2929         // Decode and validate input string
2930         $input = strtolower( $input );
2931         for( $i = 0; $i < strlen( $input ); $i++ ) {
2932                 $n = strpos( $digitChars, $input[$i] );
2933                 if( $n === false || $n > $sourceBase ) {
2934                         return false;
2935                 }
2936                 $inDigits[] = $n;
2937         }
2938
2939         // Iterate over the input, modulo-ing out an output digit
2940         // at a time until input is gone.
2941         while( count( $inDigits ) ) {
2942                 $work = 0;
2943                 $workDigits = array();
2944
2945                 // Long division...
2946                 foreach( $inDigits as $digit ) {
2947                         $work *= $sourceBase;
2948                         $work += $digit;
2949
2950                         if( $work < $destBase ) {
2951                                 // Gonna need to pull another digit.
2952                                 if( count( $workDigits ) ) {
2953                                         // Avoid zero-padding; this lets us find
2954                                         // the end of the input very easily when
2955                                         // length drops to zero.
2956                                         $workDigits[] = 0;
2957                                 }
2958                         } else {
2959                                 // Finally! Actual division!
2960                                 $workDigits[] = intval( $work / $destBase );
2961
2962                                 // Isn't it annoying that most programming languages
2963                                 // don't have a single divide-and-remainder operator,
2964                                 // even though the CPU implements it that way?
2965                                 $work = $work % $destBase;
2966                         }
2967                 }
2968
2969                 // All that division leaves us with a remainder,
2970                 // which is conveniently our next output digit.
2971                 $outChars .= $digitChars[$work];
2972
2973                 // And we continue!
2974                 $inDigits = $workDigits;
2975         }
2976
2977         while( strlen( $outChars ) < $pad ) {
2978                 $outChars .= '0';
2979         }
2980
2981         return strrev( $outChars );
2982 }
2983
2984 /**
2985  * Create an object with a given name and an array of construct parameters
2986  *
2987  * @param $name String
2988  * @param $p Array: parameters
2989  * @deprecated since 1.18, warnings in 1.19, removal in 1.20
2990  */
2991 function wfCreateObject( $name, $p ) {
2992         wfDeprecated( __FUNCTION__ );
2993         return MWFunction::newObj( $name, $p );
2994 }
2995
2996 function wfHttpOnlySafe() {
2997         global $wgHttpOnlyBlacklist;
2998
2999         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3000                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3001                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3002                                 return false;
3003                         }
3004                 }
3005         }
3006
3007         return true;
3008 }
3009
3010 /**
3011  * Initialise php session
3012  *
3013  * @param $sessionId Bool
3014  */
3015 function wfSetupSession( $sessionId = false ) {
3016         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3017                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3018         if( $wgSessionsInMemcached ) {
3019                 if ( !defined( 'MW_COMPILED' ) ) {
3020                         global $IP;
3021                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3022                 }
3023                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3024                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3025
3026                 // It's necessary to register a shutdown function to call session_write_close(),
3027                 // because by the time the request shutdown function for the session module is
3028                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3029                 // this way are called before object destruction.
3030                 register_shutdown_function( 'memsess_write_close' );
3031         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3032                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3033                 # hasn't already been set to the desired value (that causes errors)
3034                 ini_set( 'session.save_handler', $wgSessionHandler );
3035         }
3036         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3037         wfDebugLog( 'cookie',
3038                 'session_set_cookie_params: "' . implode( '", "',
3039                         array(
3040                                 0,
3041                                 $wgCookiePath,
3042                                 $wgCookieDomain,
3043                                 $wgCookieSecure,
3044                                 $httpOnlySafe ) ) . '"' );
3045         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3046         session_cache_limiter( 'private, must-revalidate' );
3047         if ( $sessionId ) {
3048                 session_id( $sessionId );
3049         }
3050         wfSuppressWarnings();
3051         session_start();
3052         wfRestoreWarnings();
3053 }
3054
3055 /**
3056  * Get an object from the precompiled serialized directory
3057  *
3058  * @param $name String
3059  * @return Mixed: the variable on success, false on failure
3060  */
3061 function wfGetPrecompiledData( $name ) {
3062         global $IP;
3063
3064         $file = "$IP/serialized/$name";
3065         if ( file_exists( $file ) ) {
3066                 $blob = file_get_contents( $file );
3067                 if ( $blob ) {
3068                         return unserialize( $blob );
3069                 }
3070         }
3071         return false;
3072 }
3073
3074 /**
3075  * Get a cache key
3076  *
3077  * @param varargs
3078  * @return String
3079  */
3080 function wfMemcKey( /*... */ ) {
3081         $args = func_get_args();
3082         $key = wfWikiID() . ':' . implode( ':', $args );
3083         $key = str_replace( ' ', '_', $key );
3084         return $key;
3085 }
3086
3087 /**
3088  * Get a cache key for a foreign DB
3089  *
3090  * @param $db String
3091  * @param $prefix String
3092  * @param varargs String
3093  * @return String
3094  */
3095 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3096         $args = array_slice( func_get_args(), 2 );
3097         if ( $prefix ) {
3098                 $key = "$db-$prefix:" . implode( ':', $args );
3099         } else {
3100                 $key = $db . ':' . implode( ':', $args );
3101         }
3102         return $key;
3103 }
3104
3105 /**
3106  * Get an ASCII string identifying this wiki
3107  * This is used as a prefix in memcached keys
3108  *
3109  * @return String
3110  */
3111 function wfWikiID() {
3112         global $wgDBprefix, $wgDBname;
3113         if ( $wgDBprefix ) {
3114                 return "$wgDBname-$wgDBprefix";
3115         } else {
3116                 return $wgDBname;
3117         }
3118 }
3119
3120 /**
3121  * Split a wiki ID into DB name and table prefix
3122  *
3123  * @param $wiki String
3124  * @param $bits String
3125  */
3126 function wfSplitWikiID( $wiki ) {
3127         $bits = explode( '-', $wiki, 2 );
3128         if ( count( $bits ) < 2 ) {
3129                 $bits[] = '';
3130         }
3131         return $bits;
3132 }
3133
3134 /**
3135  * Get a Database object.
3136  *
3137  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3138  *            master (for write queries), DB_SLAVE for potentially lagged read
3139  *            queries, or an integer >= 0 for a particular server.
3140  *
3141  * @param $groups Mixed: query groups. An array of group names that this query
3142  *                belongs to. May contain a single string if the query is only
3143  *                in one group.
3144  *
3145  * @param $wiki String: the wiki ID, or false for the current wiki
3146  *
3147  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3148  * will always return the same object, unless the underlying connection or load
3149  * balancer is manually destroyed.
3150  *
3151  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3152  * updater to ensure that a proper database is being updated.
3153  *
3154  * @return DatabaseBase
3155  */
3156 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3157         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3158 }
3159
3160 /**
3161  * Get a load balancer object.
3162  *
3163  * @param $wiki String: wiki ID, or false for the current wiki
3164  * @return LoadBalancer
3165  */
3166 function wfGetLB( $wiki = false ) {
3167         return wfGetLBFactory()->getMainLB( $wiki );
3168 }
3169
3170 /**
3171  * Get the load balancer factory object
3172  *
3173  * @return LBFactory
3174  */
3175 function &wfGetLBFactory() {
3176         return LBFactory::singleton();
3177 }
3178
3179 /**
3180  * Find a file.
3181  * Shortcut for RepoGroup::singleton()->findFile()
3182  *
3183  * @param $title String or Title object
3184  * @param $options Associative array of options:
3185  *     time:           requested time for an archived image, or false for the
3186  *                     current version. An image object will be returned which was
3187  *                     created at the specified time.
3188  *
3189  *     ignoreRedirect: If true, do not follow file redirects
3190  *
3191  *     private:        If true, return restricted (deleted) files if the current
3192  *                     user is allowed to view them. Otherwise, such files will not
3193  *                     be found.
3194  *
3195  *     bypassCache:    If true, do not use the process-local cache of File objects
3196  *
3197  * @return File, or false if the file does not exist
3198  */
3199 function wfFindFile( $title, $options = array() ) {
3200         return RepoGroup::singleton()->findFile( $title, $options );
3201 }
3202
3203 /**
3204  * Get an object referring to a locally registered file.
3205  * Returns a valid placeholder object if the file does not exist.
3206  *
3207  * @param $title Title or String
3208  * @return File, or null if passed an invalid Title
3209  */
3210 function wfLocalFile( $title ) {
3211         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3212 }
3213
3214 /**
3215  * Should low-performance queries be disabled?
3216  *
3217  * @return Boolean
3218  * @codeCoverageIgnore
3219  */
3220 function wfQueriesMustScale() {
3221         global $wgMiserMode;
3222         return $wgMiserMode
3223                 || ( SiteStats::pages() > 100000
3224                 && SiteStats::edits() > 1000000
3225                 && SiteStats::users() > 10000 );
3226 }
3227
3228 /**
3229  * Get the path to a specified script file, respecting file
3230  * extensions; this is a wrapper around $wgScriptExtension etc.
3231  *
3232  * @param $script String: script filename, sans extension
3233  * @return String
3234  */
3235 function wfScript( $script = 'index' ) {
3236         global $wgScriptPath, $wgScriptExtension;
3237         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3238 }
3239
3240 /**
3241  * Get the script URL.
3242  *
3243  * @return script URL
3244  */
3245 function wfGetScriptUrl() {
3246         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3247                 #
3248                 # as it was called, minus the query string.
3249                 #
3250                 # Some sites use Apache rewrite rules to handle subdomains,
3251                 # and have PHP set up in a weird way that causes PHP_SELF
3252                 # to contain the rewritten URL instead of the one that the
3253                 # outside world sees.
3254                 #
3255                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3256                 # provides containing the "before" URL.
3257                 return $_SERVER['SCRIPT_NAME'];
3258         } else {
3259                 return $_SERVER['URL'];
3260         }
3261 }
3262
3263 /**
3264  * Convenience function converts boolean values into "true"
3265  * or "false" (string) values
3266  *
3267  * @param $value Boolean
3268  * @return String
3269  */
3270 function wfBoolToStr( $value ) {
3271         return $value ? 'true' : 'false';
3272 }
3273
3274 /**
3275  * Load an extension messages file
3276  *
3277  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3278  * @codeCoverageIgnore
3279  */
3280 function wfLoadExtensionMessages() {
3281         wfDeprecated( __FUNCTION__ );
3282 }
3283
3284 /**
3285  * Get a platform-independent path to the null file, e.g. /dev/null
3286  *
3287  * @return string
3288  */
3289 function wfGetNull() {
3290         return wfIsWindows()
3291                 ? 'NUL'
3292                 : '/dev/null';
3293 }
3294
3295 /**
3296  * Throws a warning that $function is deprecated
3297  *
3298  * @param $function String
3299  * @return null
3300  */
3301 function wfDeprecated( $function ) {
3302         static $functionsWarned = array();
3303         if ( !isset( $functionsWarned[$function] ) ) {
3304                 $functionsWarned[$function] = true;
3305                 wfWarn( "Use of $function is deprecated.", 2 );
3306         }
3307 }
3308
3309 /**
3310  * Send a warning either to the debug log or in a PHP error depending on
3311  * $wgDevelopmentWarnings
3312  *
3313  * @param $msg String: message to send
3314  * @param $callerOffset Integer: number of items to go back in the backtrace to
3315  *        find the correct caller (1 = function calling wfWarn, ...)
3316  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3317  *        is true
3318  */
3319 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3320         global $wgDevelopmentWarnings;
3321
3322         $callers = wfDebugBacktrace();
3323         if ( isset( $callers[$callerOffset + 1] ) ) {
3324                 $callerfunc = $callers[$callerOffset + 1];
3325                 $callerfile = $callers[$callerOffset];
3326                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3327                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3328                 } else {
3329                         $file = '(internal function)';
3330                 }
3331                 $func = '';
3332                 if ( isset( $callerfunc['class'] ) ) {
3333                         $func .= $callerfunc['class'] . '::';
3334                 }
3335                 if ( isset( $callerfunc['function'] ) ) {
3336                         $func .= $callerfunc['function'];
3337                 }
3338                 $msg .= " [Called from $func in $file]";
3339         }
3340
3341         if ( $wgDevelopmentWarnings ) {
3342                 trigger_error( $msg, $level );
3343         } else {
3344                 wfDebug( "$msg\n" );
3345         }
3346 }
3347
3348 /**
3349  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3350  * and waiting for it to go down, this waits for the slaves to catch up to the
3351  * master position. Use this when updating very large numbers of rows, as
3352  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3353  * a no-op if there are no slaves.
3354  *
3355  * @param $maxLag Integer (deprecated)
3356  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3357  * @return null
3358  */
3359 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3360         $lb = wfGetLB( $wiki );
3361         // bug 27975 - Don't try to wait for slaves if there are none
3362         // Prevents permission error when getting master position
3363         if ( $lb->getServerCount() > 1 ) {
3364                 $dbw = $lb->getConnection( DB_MASTER );
3365                 $pos = $dbw->getMasterPos();
3366                 $lb->waitForAll( $pos );
3367         }
3368 }
3369
3370 /**
3371  * Used to be used for outputting text in the installer/updater
3372  * @deprecated since 1.18, warnings in 1.19, remove in 1.20
3373  */
3374 function wfOut( $s ) {
3375         wfDeprecated( __METHOD__ );
3376         global $wgCommandLineMode;
3377         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3378                 echo $s;
3379         } else {
3380                 echo htmlspecialchars( $s );
3381         }
3382         flush();
3383 }
3384
3385 /**
3386  * Count down from $n to zero on the terminal, with a one-second pause
3387  * between showing each number. For use in command-line scripts.
3388  * @codeCoverageIgnore
3389  */
3390 function wfCountDown( $n ) {
3391         for ( $i = $n; $i >= 0; $i-- ) {
3392                 if ( $i != $n ) {
3393                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3394                 }
3395                 echo $i;
3396                 flush();
3397                 if ( $i ) {
3398                         sleep( 1 );
3399                 }
3400         }
3401         echo "\n";
3402 }
3403
3404 /**
3405  * Generate a random 32-character hexadecimal token.
3406  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3407  *              characters before hashing.
3408  * @return string
3409  * @codeCoverageIgnore
3410  */
3411 function wfGenerateToken( $salt = '' ) {
3412         $salt = serialize( $salt );
3413         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3414 }
3415
3416 /**
3417  * Replace all invalid characters with -
3418  *
3419  * @param $name Mixed: filename to process
3420  * @return String
3421  */
3422 function wfStripIllegalFilenameChars( $name ) {
3423         global $wgIllegalFileChars;
3424         $name = wfBaseName( $name );
3425         $name = preg_replace(
3426                 "/[^" . Title::legalChars() . "]" .
3427                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3428                         "/",
3429                 '-',
3430                 $name
3431         );
3432         return $name;
3433 }
3434
3435 /**
3436  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3437  *
3438  * @return Integer value memory was set to.
3439  */
3440 function wfMemoryLimit() {
3441         global $wgMemoryLimit;
3442         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3443         if( $memlimit != -1 ) {
3444                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3445                 if( $conflimit == -1 ) {
3446                         wfDebug( "Removing PHP's memory limit\n" );
3447                         wfSuppressWarnings();
3448                         ini_set( 'memory_limit', $conflimit );
3449                         wfRestoreWarnings();
3450                         return $conflimit;
3451                 } elseif ( $conflimit > $memlimit ) {
3452                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3453                         wfSuppressWarnings();
3454                         ini_set( 'memory_limit', $conflimit );
3455                         wfRestoreWarnings();
3456                         return $conflimit;
3457                 }
3458         }
3459         return $memlimit;
3460 }
3461
3462 /**
3463  * Converts shorthand byte notation to integer form
3464  *
3465  * @param $string String
3466  * @return Integer
3467  */
3468 function wfShorthandToInteger( $string = '' ) {
3469         $string = trim( $string );
3470         if( $string === '' ) {
3471                 return -1;
3472         }
3473         $last = $string[strlen( $string ) - 1];
3474         $val = intval( $string );
3475         switch( $last ) {
3476                 case 'g':
3477                 case 'G':
3478                         $val *= 1024;
3479                         // break intentionally missing
3480                 case 'm':
3481                 case 'M':
3482                         $val *= 1024;
3483                         // break intentionally missing
3484                 case 'k':
3485                 case 'K':
3486                         $val *= 1024;
3487         }
3488
3489         return $val;
3490 }
3491
3492 /**
3493  * Get the normalised IETF language tag
3494  * See unit test for examples.
3495  *
3496  * @param $code String: The language code.
3497  * @return $langCode String: The language code which complying with BCP 47 standards.
3498  */
3499 function wfBCP47( $code ) {
3500         $codeSegment = explode( '-', $code );
3501         $codeBCP = array();
3502         foreach ( $codeSegment as $segNo => $seg ) {
3503                 if ( count( $codeSegment ) > 0 ) {
3504                         // when previous segment is x, it is a private segment and should be lc
3505                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3506                                 $codeBCP[$segNo] = strtolower( $seg );
3507                         // ISO 3166 country code
3508                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3509                                 $codeBCP[$segNo] = strtoupper( $seg );
3510                         // ISO 15924 script code
3511                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3512                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3513                         // Use lowercase for other cases
3514                         } else {
3515                                 $codeBCP[$segNo] = strtolower( $seg );
3516                         }
3517                 } else {
3518                 // Use lowercase for single segment
3519                         $codeBCP[$segNo] = strtolower( $seg );
3520                 }
3521         }
3522         $langCode = implode( '-', $codeBCP );
3523         return $langCode;
3524 }
3525
3526 /**
3527  * Get a cache object.
3528  *
3529  * @param integer $inputType Cache type, one the the CACHE_* constants.
3530  * @return BagOStuff
3531  */
3532 function wfGetCache( $inputType ) {
3533         return ObjectCache::getInstance( $inputType );
3534 }
3535
3536 /**
3537  * Get the main cache object
3538  *
3539  * @return BagOStuff
3540  */
3541 function wfGetMainCache() {
3542         global $wgMainCacheType;
3543         return ObjectCache::getInstance( $wgMainCacheType );
3544 }
3545
3546 /**
3547  * Get the cache object used by the message cache
3548  *
3549  * @return BagOStuff
3550  */
3551 function wfGetMessageCacheStorage() {
3552         global $wgMessageCacheType;
3553         return ObjectCache::getInstance( $wgMessageCacheType );
3554 }
3555
3556 /**
3557  * Get the cache object used by the parser cache
3558  *
3559  * @return BagOStuff
3560  */
3561 function wfGetParserCacheStorage() {
3562         global $wgParserCacheType;
3563         return ObjectCache::getInstance( $wgParserCacheType );
3564 }
3565
3566 /**
3567  * Call hook functions defined in $wgHooks
3568  *
3569  * @param $event String: event name
3570  * @param $args Array: parameters passed to hook functions
3571  * @return Boolean
3572  */
3573 function wfRunHooks( $event, $args = array() ) {
3574         return Hooks::run( $event, $args );
3575 }