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  * and $wgProto are 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         if( substr( $url, 0, 2 ) == '//' ) {
1586                 global $wgProto;
1587                 return $wgProto . ':' . $url;
1588         } elseif( substr( $url, 0, 1 ) == '/' ) {
1589                 global $wgServer;
1590                 return $wgServer . $url;
1591         } else {
1592                 return $url;
1593         }
1594 }
1595
1596 /**
1597  * Windows-compatible version of escapeshellarg()
1598  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1599  * function puts single quotes in regardless of OS.
1600  *
1601  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1602  * earlier distro releases of PHP)
1603  *
1604  * @param varargs
1605  * @return String
1606  */
1607 function wfEscapeShellArg( ) {
1608         wfInitShellLocale();
1609
1610         $args = func_get_args();
1611         $first = true;
1612         $retVal = '';
1613         foreach ( $args as $arg ) {
1614                 if ( !$first ) {
1615                         $retVal .= ' ';
1616                 } else {
1617                         $first = false;
1618                 }
1619
1620                 if ( wfIsWindows() ) {
1621                         // Escaping for an MSVC-style command line parser and CMD.EXE
1622                         // Refs:
1623                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1624                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1625                         //  * Bug #13518
1626                         //  * CR r63214
1627                         // Double the backslashes before any double quotes. Escape the double quotes.
1628                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1629                         $arg = '';
1630                         $iteration = 0;
1631                         foreach ( $tokens as $token ) {
1632                                 if ( $iteration % 2 == 1 ) {
1633                                         // Delimiter, a double quote preceded by zero or more slashes
1634                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1635                                 } elseif ( $iteration % 4 == 2 ) {
1636                                         // ^ in $token will be outside quotes, need to be escaped
1637                                         $arg .= str_replace( '^', '^^', $token );
1638                                 } else { // $iteration % 4 == 0
1639                                         // ^ in $token will appear inside double quotes, so leave as is
1640                                         $arg .= $token;
1641                                 }
1642                                 $iteration++;
1643                         }
1644                         // Double the backslashes before the end of the string, because
1645                         // we will soon add a quote
1646                         $m = array();
1647                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1648                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1649                         }
1650
1651                         // Add surrounding quotes
1652                         $retVal .= '"' . $arg . '"';
1653                 } else {
1654                         $retVal .= escapeshellarg( $arg );
1655                 }
1656         }
1657         return $retVal;
1658 }
1659
1660 /**
1661  * wfMerge attempts to merge differences between three texts.
1662  * Returns true for a clean merge and false for failure or a conflict.
1663  *
1664  * @param $old String
1665  * @param $mine String
1666  * @param $yours String
1667  * @param $result String
1668  * @return Bool
1669  */
1670 function wfMerge( $old, $mine, $yours, &$result ) {
1671         global $wgDiff3;
1672
1673         # This check may also protect against code injection in
1674         # case of broken installations.
1675         wfSuppressWarnings();
1676         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1677         wfRestoreWarnings();
1678
1679         if( !$haveDiff3 ) {
1680                 wfDebug( "diff3 not found\n" );
1681                 return false;
1682         }
1683
1684         # Make temporary files
1685         $td = wfTempDir();
1686         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1687         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1688         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1689
1690         fwrite( $oldtextFile, $old );
1691         fclose( $oldtextFile );
1692         fwrite( $mytextFile, $mine );
1693         fclose( $mytextFile );
1694         fwrite( $yourtextFile, $yours );
1695         fclose( $yourtextFile );
1696
1697         # Check for a conflict
1698         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1699                 wfEscapeShellArg( $mytextName ) . ' ' .
1700                 wfEscapeShellArg( $oldtextName ) . ' ' .
1701                 wfEscapeShellArg( $yourtextName );
1702         $handle = popen( $cmd, 'r' );
1703
1704         if( fgets( $handle, 1024 ) ) {
1705                 $conflict = true;
1706         } else {
1707                 $conflict = false;
1708         }
1709         pclose( $handle );
1710
1711         # Merge differences
1712         $cmd = $wgDiff3 . ' -a -e --merge ' .
1713                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1714         $handle = popen( $cmd, 'r' );
1715         $result = '';
1716         do {
1717                 $data = fread( $handle, 8192 );
1718                 if ( strlen( $data ) == 0 ) {
1719                         break;
1720                 }
1721                 $result .= $data;
1722         } while ( true );
1723         pclose( $handle );
1724         unlink( $mytextName );
1725         unlink( $oldtextName );
1726         unlink( $yourtextName );
1727
1728         if ( $result === '' && $old !== '' && !$conflict ) {
1729                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1730                 $conflict = true;
1731         }
1732         return !$conflict;
1733 }
1734
1735 /**
1736  * Returns unified plain-text diff of two texts.
1737  * Useful for machine processing of diffs.
1738  *
1739  * @param $before String: the text before the changes.
1740  * @param $after String: the text after the changes.
1741  * @param $params String: command-line options for the diff command.
1742  * @return String: unified diff of $before and $after
1743  */
1744 function wfDiff( $before, $after, $params = '-u' ) {
1745         if ( $before == $after ) {
1746                 return '';
1747         }
1748
1749         global $wgDiff;
1750         wfSuppressWarnings();
1751         $haveDiff = $wgDiff && file_exists( $wgDiff );
1752         wfRestoreWarnings();
1753
1754         # This check may also protect against code injection in
1755         # case of broken installations.
1756         if( !$haveDiff ) {
1757                 wfDebug( "diff executable not found\n" );
1758                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1759                 $format = new UnifiedDiffFormatter();
1760                 return $format->format( $diffs );
1761         }
1762
1763         # Make temporary files
1764         $td = wfTempDir();
1765         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1766         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1767
1768         fwrite( $oldtextFile, $before );
1769         fclose( $oldtextFile );
1770         fwrite( $newtextFile, $after );
1771         fclose( $newtextFile );
1772
1773         // Get the diff of the two files
1774         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1775
1776         $h = popen( $cmd, 'r' );
1777
1778         $diff = '';
1779
1780         do {
1781                 $data = fread( $h, 8192 );
1782                 if ( strlen( $data ) == 0 ) {
1783                         break;
1784                 }
1785                 $diff .= $data;
1786         } while ( true );
1787
1788         // Clean up
1789         pclose( $h );
1790         unlink( $oldtextName );
1791         unlink( $newtextName );
1792
1793         // Kill the --- and +++ lines. They're not useful.
1794         $diff_lines = explode( "\n", $diff );
1795         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1796                 unset( $diff_lines[0] );
1797         }
1798         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1799                 unset( $diff_lines[1] );
1800         }
1801
1802         $diff = implode( "\n", $diff_lines );
1803
1804         return $diff;
1805 }
1806
1807 /**
1808  * A wrapper around the PHP function var_export().
1809  * Either print it or add it to the regular output ($wgOut).
1810  *
1811  * @param $var A PHP variable to dump.
1812  */
1813 function wfVarDump( $var ) {
1814         global $wgOut;
1815         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1816         if ( headers_sent() || !@is_object( $wgOut ) ) {
1817                 print $s;
1818         } else {
1819                 $wgOut->addHTML( $s );
1820         }
1821 }
1822
1823 /**
1824  * Provide a simple HTTP error.
1825  *
1826  * @param $code Int|String
1827  * @param $label String
1828  * @param $desc String
1829  */
1830 function wfHttpError( $code, $label, $desc ) {
1831         global $wgOut;
1832         $wgOut->disable();
1833         header( "HTTP/1.0 $code $label" );
1834         header( "Status: $code $label" );
1835         $wgOut->sendCacheControl();
1836
1837         header( 'Content-type: text/html; charset=utf-8' );
1838         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1839                 '<html><head><title>' .
1840                 htmlspecialchars( $label ) .
1841                 '</title></head><body><h1>' .
1842                 htmlspecialchars( $label ) .
1843                 '</h1><p>' .
1844                 nl2br( htmlspecialchars( $desc ) ) .
1845                 "</p></body></html>\n";
1846 }
1847
1848 /**
1849  * Clear away any user-level output buffers, discarding contents.
1850  *
1851  * Suitable for 'starting afresh', for instance when streaming
1852  * relatively large amounts of data without buffering, or wanting to
1853  * output image files without ob_gzhandler's compression.
1854  *
1855  * The optional $resetGzipEncoding parameter controls suppression of
1856  * the Content-Encoding header sent by ob_gzhandler; by default it
1857  * is left. See comments for wfClearOutputBuffers() for why it would
1858  * be used.
1859  *
1860  * Note that some PHP configuration options may add output buffer
1861  * layers which cannot be removed; these are left in place.
1862  *
1863  * @param $resetGzipEncoding Bool
1864  */
1865 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1866         if( $resetGzipEncoding ) {
1867                 // Suppress Content-Encoding and Content-Length
1868                 // headers from 1.10+s wfOutputHandler
1869                 global $wgDisableOutputCompression;
1870                 $wgDisableOutputCompression = true;
1871         }
1872         while( $status = ob_get_status() ) {
1873                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1874                         // Probably from zlib.output_compression or other
1875                         // PHP-internal setting which can't be removed.
1876                         //
1877                         // Give up, and hope the result doesn't break
1878                         // output behavior.
1879                         break;
1880                 }
1881                 if( !ob_end_clean() ) {
1882                         // Could not remove output buffer handler; abort now
1883                         // to avoid getting in some kind of infinite loop.
1884                         break;
1885                 }
1886                 if( $resetGzipEncoding ) {
1887                         if( $status['name'] == 'ob_gzhandler' ) {
1888                                 // Reset the 'Content-Encoding' field set by this handler
1889                                 // so we can start fresh.
1890                                 if ( function_exists( 'header_remove' ) ) {
1891                                         // Available since PHP 5.3.0
1892                                         header_remove( 'Content-Encoding' );
1893                                 } else {
1894                                         // We need to provide a valid content-coding. See bug 28069
1895                                         header( 'Content-Encoding: identity' );
1896                                 }
1897                                 break;
1898                         }
1899                 }
1900         }
1901 }
1902
1903 /**
1904  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1905  *
1906  * Clear away output buffers, but keep the Content-Encoding header
1907  * produced by ob_gzhandler, if any.
1908  *
1909  * This should be used for HTTP 304 responses, where you need to
1910  * preserve the Content-Encoding header of the real result, but
1911  * also need to suppress the output of ob_gzhandler to keep to spec
1912  * and avoid breaking Firefox in rare cases where the headers and
1913  * body are broken over two packets.
1914  */
1915 function wfClearOutputBuffers() {
1916         wfResetOutputBuffers( false );
1917 }
1918
1919 /**
1920  * Converts an Accept-* header into an array mapping string values to quality
1921  * factors
1922  *
1923  * @param $accept String
1924  * @param $def String default
1925  * @return Array
1926  */
1927 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1928         # No arg means accept anything (per HTTP spec)
1929         if( !$accept ) {
1930                 return array( $def => 1.0 );
1931         }
1932
1933         $prefs = array();
1934
1935         $parts = explode( ',', $accept );
1936
1937         foreach( $parts as $part ) {
1938                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1939                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1940                 $match = array();
1941                 if( !isset( $qpart ) ) {
1942                         $prefs[$value] = 1.0;
1943                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1944                         $prefs[$value] = floatval( $match[1] );
1945                 }
1946         }
1947
1948         return $prefs;
1949 }
1950
1951 /**
1952  * Checks if a given MIME type matches any of the keys in the given
1953  * array. Basic wildcards are accepted in the array keys.
1954  *
1955  * Returns the matching MIME type (or wildcard) if a match, otherwise
1956  * NULL if no match.
1957  *
1958  * @param $type String
1959  * @param $avail Array
1960  * @return string
1961  * @private
1962  */
1963 function mimeTypeMatch( $type, $avail ) {
1964         if( array_key_exists( $type, $avail ) ) {
1965                 return $type;
1966         } else {
1967                 $parts = explode( '/', $type );
1968                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1969                         return $parts[0] . '/*';
1970                 } elseif( array_key_exists( '*/*', $avail ) ) {
1971                         return '*/*';
1972                 } else {
1973                         return null;
1974                 }
1975         }
1976 }
1977
1978 /**
1979  * Returns the 'best' match between a client's requested internet media types
1980  * and the server's list of available types. Each list should be an associative
1981  * array of type to preference (preference is a float between 0.0 and 1.0).
1982  * Wildcards in the types are acceptable.
1983  *
1984  * @param $cprefs Array: client's acceptable type list
1985  * @param $sprefs Array: server's offered types
1986  * @return string
1987  *
1988  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1989  * XXX: generalize to negotiate other stuff
1990  */
1991 function wfNegotiateType( $cprefs, $sprefs ) {
1992         $combine = array();
1993
1994         foreach( array_keys($sprefs) as $type ) {
1995                 $parts = explode( '/', $type );
1996                 if( $parts[1] != '*' ) {
1997                         $ckey = mimeTypeMatch( $type, $cprefs );
1998                         if( $ckey ) {
1999                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2000                         }
2001                 }
2002         }
2003
2004         foreach( array_keys( $cprefs ) as $type ) {
2005                 $parts = explode( '/', $type );
2006                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2007                         $skey = mimeTypeMatch( $type, $sprefs );
2008                         if( $skey ) {
2009                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2010                         }
2011                 }
2012         }
2013
2014         $bestq = 0;
2015         $besttype = null;
2016
2017         foreach( array_keys( $combine ) as $type ) {
2018                 if( $combine[$type] > $bestq ) {
2019                         $besttype = $type;
2020                         $bestq = $combine[$type];
2021                 }
2022         }
2023
2024         return $besttype;
2025 }
2026
2027 /**
2028  * Reference-counted warning suppression
2029  *
2030  * @param $end Bool
2031  */
2032 function wfSuppressWarnings( $end = false ) {
2033         static $suppressCount = 0;
2034         static $originalLevel = false;
2035
2036         if ( $end ) {
2037                 if ( $suppressCount ) {
2038                         --$suppressCount;
2039                         if ( !$suppressCount ) {
2040                                 error_reporting( $originalLevel );
2041                         }
2042                 }
2043         } else {
2044                 if ( !$suppressCount ) {
2045                         // E_DEPRECATED is undefined in PHP 5.2
2046                         if( !defined( 'E_DEPRECATED' ) ){
2047                                 define( 'E_DEPRECATED', 8192 );
2048                         }
2049                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2050                 }
2051                 ++$suppressCount;
2052         }
2053 }
2054
2055 /**
2056  * Restore error level to previous value
2057  */
2058 function wfRestoreWarnings() {
2059         wfSuppressWarnings( true );
2060 }
2061
2062 # Autodetect, convert and provide timestamps of various types
2063
2064 /**
2065  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2066  */
2067 define( 'TS_UNIX', 0 );
2068
2069 /**
2070  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2071  */
2072 define( 'TS_MW', 1 );
2073
2074 /**
2075  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2076  */
2077 define( 'TS_DB', 2 );
2078
2079 /**
2080  * RFC 2822 format, for E-mail and HTTP headers
2081  */
2082 define( 'TS_RFC2822', 3 );
2083
2084 /**
2085  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2086  *
2087  * This is used by Special:Export
2088  */
2089 define( 'TS_ISO_8601', 4 );
2090
2091 /**
2092  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2093  *
2094  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2095  *       DateTime tag and page 36 for the DateTimeOriginal and
2096  *       DateTimeDigitized tags.
2097  */
2098 define( 'TS_EXIF', 5 );
2099
2100 /**
2101  * Oracle format time.
2102  */
2103 define( 'TS_ORACLE', 6 );
2104
2105 /**
2106  * Postgres format time.
2107  */
2108 define( 'TS_POSTGRES', 7 );
2109
2110 /**
2111  * DB2 format time
2112  */
2113 define( 'TS_DB2', 8 );
2114
2115 /**
2116  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2117  */
2118 define( 'TS_ISO_8601_BASIC', 9 );
2119
2120 /**
2121  * Get a timestamp string in one of various formats
2122  *
2123  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2124  *                    function will autodetect which format is supplied and act
2125  *                    accordingly.
2126  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2127  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2128  */
2129 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2130         $uts = 0;
2131         $da = array();
2132         $strtime = '';
2133
2134         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2135                 $uts = time();
2136                 $strtime = "@$uts";
2137         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2138                 # TS_DB
2139         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2140                 # TS_EXIF
2141         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2142                 # TS_MW
2143         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2144                 # TS_UNIX
2145                 $uts = $ts;
2146                 $strtime = "@$ts"; // Undocumented?
2147         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2148                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2149                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2150                                 str_replace( '+00:00', 'UTC', $ts ) );
2151         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2152                 # TS_ISO_8601
2153         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2154                 #TS_ISO_8601_BASIC
2155         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2156                 # TS_POSTGRES
2157         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2158                 # TS_POSTGRES
2159         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2160                 # TS_DB2
2161         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2162                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2163                                                         '[ \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
2164                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2165                 # The regex is a superset of rfc2822 for readability
2166                 $strtime = strtok( $ts, ';' );
2167         } 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 ) ) {
2168                 # TS_RFC850
2169                 $strtime = $ts;
2170         } 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 ) ) {
2171                 # asctime
2172                 $strtime = $ts;
2173         } else {
2174                 # Bogus value...
2175                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2176
2177                 return false;
2178         }
2179
2180         static $formats = array(
2181                 TS_UNIX => 'U',
2182                 TS_MW => 'YmdHis',
2183                 TS_DB => 'Y-m-d H:i:s',
2184                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2185                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2186                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2187                 TS_RFC2822 => 'D, d M Y H:i:s',
2188                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2189                 TS_POSTGRES => 'Y-m-d H:i:s',
2190                 TS_DB2 => 'Y-m-d H:i:s',
2191         );
2192
2193         if ( !isset( $formats[$outputtype] ) ) {
2194                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2195         }
2196
2197         if ( function_exists( "date_create" ) ) {
2198                 if ( count( $da ) ) {
2199                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2200                                 (int)$da[1], (int)$da[2], (int)$da[3],
2201                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2202
2203                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2204                 } elseif ( $strtime ) {
2205                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2206                 } else {
2207                         return false;
2208                 }
2209
2210                 if ( !$d ) {
2211                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2212                         return false;
2213                 }
2214
2215                 $output = $d->format( $formats[$outputtype] );
2216         } else {
2217                 if ( count( $da ) ) {
2218                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2219                         // We may want to handle that explicitly at some point
2220                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2221                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2222                 } elseif ( $strtime ) {
2223                         $uts = strtotime( $strtime );
2224                 }
2225
2226                 if ( $uts === false ) {
2227                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2228                         return false;
2229                 }
2230
2231                 if ( TS_UNIX == $outputtype ) {
2232                         return $uts;
2233                 }
2234                 $output = gmdate( $formats[$outputtype], $uts );
2235         }
2236
2237         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2238                 $output .= ' GMT';
2239         }
2240
2241         return $output;
2242 }
2243
2244 /**
2245  * Return a formatted timestamp, or null if input is null.
2246  * For dealing with nullable timestamp columns in the database.
2247  *
2248  * @param $outputtype Integer
2249  * @param $ts String
2250  * @return String
2251  */
2252 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2253         if( is_null( $ts ) ) {
2254                 return null;
2255         } else {
2256                 return wfTimestamp( $outputtype, $ts );
2257         }
2258 }
2259
2260 /**
2261  * Convenience function; returns MediaWiki timestamp for the present time.
2262  *
2263  * @return string
2264  */
2265 function wfTimestampNow() {
2266         # return NOW
2267         return wfTimestamp( TS_MW, time() );
2268 }
2269
2270 /**
2271  * Check if the operating system is Windows
2272  *
2273  * @return Bool: true if it's Windows, False otherwise.
2274  */
2275 function wfIsWindows() {
2276         static $isWindows = null;
2277         if ( $isWindows === null ) {
2278                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2279         }
2280         return $isWindows;
2281 }
2282
2283 /**
2284  * Check if we are running under HipHop
2285  *
2286  * @return Bool
2287  */
2288 function wfIsHipHop() {
2289         return function_exists( 'hphp_thread_set_warmup_enabled' );
2290 }
2291
2292 /**
2293  * Swap two variables
2294  *
2295  * @param $x Mixed
2296  * @param $y Mixed
2297  */
2298 function swap( &$x, &$y ) {
2299         $z = $x;
2300         $x = $y;
2301         $y = $z;
2302 }
2303
2304 /**
2305  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2306  * TEMP environment variables are then checked in sequence, and if none are set
2307  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2308  * or C:\Windows\Temp for Windows and hope for the best.
2309  * It is common to call it with tempnam().
2310  *
2311  * NOTE: When possible, use instead the tmpfile() function to create
2312  * temporary files to avoid race conditions on file creation, etc.
2313  *
2314  * @return String
2315  */
2316 function wfTempDir() {
2317         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2318                 $tmp = getenv( $var );
2319                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2320                         return $tmp;
2321                 }
2322         }
2323         if( function_exists( 'sys_get_temp_dir' ) ) {
2324                 return sys_get_temp_dir();
2325         }
2326         # Usual defaults
2327         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2328 }
2329
2330 /**
2331  * Make directory, and make all parent directories if they don't exist
2332  *
2333  * @param $dir String: full path to directory to create
2334  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2335  * @param $caller String: optional caller param for debugging.
2336  * @return bool
2337  */
2338 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2339         global $wgDirectoryMode;
2340
2341         if ( !is_null( $caller ) ) {
2342                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2343         }
2344
2345         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2346                 return true;
2347         }
2348
2349         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2350
2351         if ( is_null( $mode ) ) {
2352                 $mode = $wgDirectoryMode;
2353         }
2354
2355         // Turn off the normal warning, we're doing our own below
2356         wfSuppressWarnings();
2357         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2358         wfRestoreWarnings();
2359
2360         if( !$ok ) {
2361                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2362                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2363         }
2364         return $ok;
2365 }
2366
2367 /**
2368  * Increment a statistics counter
2369  *
2370  * @param $key String
2371  * @param $count Int
2372  */
2373 function wfIncrStats( $key, $count = 1 ) {
2374         global $wgStatsMethod;
2375
2376         $count = intval( $count );
2377
2378         if( $wgStatsMethod == 'udp' ) {
2379                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2380                 static $socket;
2381
2382                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2383
2384                 if ( !$socket ) {
2385                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2386                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2387                         socket_sendto(
2388                                 $socket,
2389                                 $statline,
2390                                 strlen( $statline ),
2391                                 0,
2392                                 $wgUDPProfilerHost,
2393                                 $wgUDPProfilerPort
2394                         );
2395                 }
2396                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2397                 wfSuppressWarnings();
2398                 socket_sendto(
2399                         $socket,
2400                         $statline,
2401                         strlen( $statline ),
2402                         0,
2403                         $wgUDPProfilerHost,
2404                         $wgUDPProfilerPort
2405                 );
2406                 wfRestoreWarnings();
2407         } elseif( $wgStatsMethod == 'cache' ) {
2408                 global $wgMemc;
2409                 $key = wfMemcKey( 'stats', $key );
2410                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2411                         $wgMemc->add( $key, $count );
2412                 }
2413         } else {
2414                 // Disabled
2415         }
2416 }
2417
2418 /**
2419  * @param $nr Mixed: the number to format
2420  * @param $acc Integer: the number of digits after the decimal point, default 2
2421  * @param $round Boolean: whether or not to round the value, default true
2422  * @return float
2423  */
2424 function wfPercent( $nr, $acc = 2, $round = true ) {
2425         $ret = sprintf( "%.${acc}f", $nr );
2426         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2427 }
2428
2429 /**
2430  * Find out whether or not a mixed variable exists in a string
2431  *
2432  * @param $needle String
2433  * @param $str String
2434  * @param $insensitive Boolean
2435  * @return Boolean
2436  */
2437 function in_string( $needle, $str, $insensitive = false ) {
2438         $func = 'strpos';
2439         if( $insensitive ) $func = 'stripos';
2440
2441         return $func( $str, $needle ) !== false;
2442 }
2443
2444 function wfSpecialList( $page, $details ) {
2445         global $wgContLang;
2446         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2447         return $page . $details;
2448 }
2449
2450 /**
2451  * Returns a regular expression of url protocols
2452  *
2453  * @return String
2454  */
2455 function wfUrlProtocols() {
2456         global $wgUrlProtocols;
2457
2458         static $retval = null;
2459         if ( !is_null( $retval ) ) {
2460                 return $retval;
2461         }
2462
2463         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2464         // with LocalSettings files from 1.5
2465         if ( is_array( $wgUrlProtocols ) ) {
2466                 $protocols = array();
2467                 foreach ( $wgUrlProtocols as $protocol ) {
2468                         $protocols[] = preg_quote( $protocol, '/' );
2469                 }
2470
2471                 $retval = implode( '|', $protocols );
2472         } else {
2473                 $retval = $wgUrlProtocols;
2474         }
2475         return $retval;
2476 }
2477
2478 /**
2479  * Safety wrapper around ini_get() for boolean settings.
2480  * The values returned from ini_get() are pre-normalized for settings
2481  * set via php.ini or php_flag/php_admin_flag... but *not*
2482  * for those set via php_value/php_admin_value.
2483  *
2484  * It's fairly common for people to use php_value instead of php_flag,
2485  * which can leave you with an 'off' setting giving a false positive
2486  * for code that just takes the ini_get() return value as a boolean.
2487  *
2488  * To make things extra interesting, setting via php_value accepts
2489  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2490  * Unrecognized values go false... again opposite PHP's own coercion
2491  * from string to bool.
2492  *
2493  * Luckily, 'properly' set settings will always come back as '0' or '1',
2494  * so we only have to worry about them and the 'improper' settings.
2495  *
2496  * I frickin' hate PHP... :P
2497  *
2498  * @param $setting String
2499  * @return Bool
2500  */
2501 function wfIniGetBool( $setting ) {
2502         $val = ini_get( $setting );
2503         // 'on' and 'true' can't have whitespace around them, but '1' can.
2504         return strtolower( $val ) == 'on'
2505                 || strtolower( $val ) == 'true'
2506                 || strtolower( $val ) == 'yes'
2507                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2508 }
2509
2510 /**
2511  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2512  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2513  *
2514  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2515  *                          should be omitted
2516  * @param $fileName String Name of the library, if not $extension.suffix
2517  * @return Bool - Whether or not the extension is loaded
2518  */
2519 function wfDl( $extension, $fileName = null ) {
2520         if( extension_loaded( $extension ) ) {
2521                 return true;
2522         }
2523
2524         $canDl = false;
2525         $sapi = php_sapi_name();
2526         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2527                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2528         {
2529                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2530                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2531         }
2532
2533         if( $canDl ) {
2534                 $fileName = $fileName ? $fileName : $extension;
2535                 if( wfIsWindows() ) {
2536                         $fileName = 'php_' . $fileName;
2537                 }
2538                 wfSuppressWarnings();
2539                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2540                 wfRestoreWarnings();
2541         }
2542         return extension_loaded( $extension );
2543 }
2544
2545 /**
2546  * Execute a shell command, with time and memory limits mirrored from the PHP
2547  * configuration if supported.
2548  * @param $cmd String Command line, properly escaped for shell.
2549  * @param &$retval optional, will receive the program's exit code.
2550  *                 (non-zero is usually failure)
2551  * @param $environ Array optional environment variables which should be
2552  *                 added to the executed command environment.
2553  * @return collected stdout as a string (trailing newlines stripped)
2554  */
2555 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2556         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2557
2558         static $disabled;
2559         if ( is_null( $disabled ) ) {
2560                 $disabled = false;
2561                 if( wfIniGetBool( 'safe_mode' ) ) {
2562                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2563                         $disabled = 'safemode';
2564                 } else {
2565                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2566                         $functions = array_map( 'trim', $functions );
2567                         $functions = array_map( 'strtolower', $functions );
2568                         if ( in_array( 'passthru', $functions ) ) {
2569                                 wfDebug( "passthru is in disabled_functions\n" );
2570                                 $disabled = 'passthru';
2571                         }
2572                 }
2573         }
2574         if ( $disabled ) {
2575                 $retval = 1;
2576                 return $disabled == 'safemode' ?
2577                         'Unable to run external programs in safe mode.' :
2578                         'Unable to run external programs, passthru() is disabled.';
2579         }
2580
2581         wfInitShellLocale();
2582
2583         $envcmd = '';
2584         foreach( $environ as $k => $v ) {
2585                 if ( wfIsWindows() ) {
2586                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2587                          * appear in the environment variable, so we must use carat escaping as documented in
2588                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2589                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2590                          * are listed there but doesn't appear to need it.
2591                          */
2592                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2593                 } else {
2594                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2595                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2596                          */
2597                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2598                 }
2599         }
2600         $cmd = $envcmd . $cmd;
2601
2602         if ( wfIsWindows() ) {
2603                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2604                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2605                 {
2606                         # Hack to work around PHP's flawed invocation of cmd.exe
2607                         # http://news.php.net/php.internals/21796
2608                         # Windows 9x doesn't accept any kind of quotes
2609                         $cmd = '"' . $cmd . '"';
2610                 }
2611         } elseif ( php_uname( 's' ) == 'Linux' ) {
2612                 $time = intval( $wgMaxShellTime );
2613                 $mem = intval( $wgMaxShellMemory );
2614                 $filesize = intval( $wgMaxShellFileSize );
2615
2616                 if ( $time > 0 && $mem > 0 ) {
2617                         $script = "$IP/bin/ulimit4.sh";
2618                         if ( is_executable( $script ) ) {
2619                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2620                         }
2621                 }
2622         }
2623         wfDebug( "wfShellExec: $cmd\n" );
2624
2625         $retval = 1; // error by default?
2626         ob_start();
2627         passthru( $cmd, $retval );
2628         $output = ob_get_contents();
2629         ob_end_clean();
2630
2631         if ( $retval == 127 ) {
2632                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2633         }
2634         return $output;
2635 }
2636
2637 /**
2638  * Workaround for http://bugs.php.net/bug.php?id=45132
2639  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2640  */
2641 function wfInitShellLocale() {
2642         static $done = false;
2643         if ( $done ) {
2644                 return;
2645         }
2646         $done = true;
2647         global $wgShellLocale;
2648         if ( !wfIniGetBool( 'safe_mode' ) ) {
2649                 putenv( "LC_CTYPE=$wgShellLocale" );
2650                 setlocale( LC_CTYPE, $wgShellLocale );
2651         }
2652 }
2653
2654 /**
2655  * This function works like "use VERSION" in Perl, the program will die with a
2656  * backtrace if the current version of PHP is less than the version provided
2657  *
2658  * This is useful for extensions which due to their nature are not kept in sync
2659  * with releases, and might depend on other versions of PHP than the main code
2660  *
2661  * Note: PHP might die due to parsing errors in some cases before it ever
2662  *       manages to call this function, such is life
2663  *
2664  * @see perldoc -f use
2665  *
2666  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2667  *                 a float
2668  */
2669 function wfUsePHP( $req_ver ) {
2670         $php_ver = PHP_VERSION;
2671
2672         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2673                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2674         }
2675 }
2676
2677 /**
2678  * This function works like "use VERSION" in Perl except it checks the version
2679  * of MediaWiki, the program will die with a backtrace if the current version
2680  * of MediaWiki is less than the version provided.
2681  *
2682  * This is useful for extensions which due to their nature are not kept in sync
2683  * with releases
2684  *
2685  * @see perldoc -f use
2686  *
2687  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2688  *                 a float
2689  */
2690 function wfUseMW( $req_ver ) {
2691         global $wgVersion;
2692
2693         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2694                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2695         }
2696 }
2697
2698 /**
2699  * Return the final portion of a pathname.
2700  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2701  * http://bugs.php.net/bug.php?id=33898
2702  *
2703  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2704  * We'll consider it so always, as we don't want \s in our Unix paths either.
2705  *
2706  * @param $path String
2707  * @param $suffix String: to remove if present
2708  * @return String
2709  */
2710 function wfBaseName( $path, $suffix = '' ) {
2711         $encSuffix = ( $suffix == '' )
2712                 ? ''
2713                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2714         $matches = array();
2715         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2716                 return $matches[1];
2717         } else {
2718                 return '';
2719         }
2720 }
2721
2722 /**
2723  * Generate a relative path name to the given file.
2724  * May explode on non-matching case-insensitive paths,
2725  * funky symlinks, etc.
2726  *
2727  * @param $path String: absolute destination path including target filename
2728  * @param $from String: Absolute source path, directory only
2729  * @return String
2730  */
2731 function wfRelativePath( $path, $from ) {
2732         // Normalize mixed input on Windows...
2733         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2734         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2735
2736         // Trim trailing slashes -- fix for drive root
2737         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2738         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2739
2740         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2741         $against = explode( DIRECTORY_SEPARATOR, $from );
2742
2743         if( $pieces[0] !== $against[0] ) {
2744                 // Non-matching Windows drive letters?
2745                 // Return a full path.
2746                 return $path;
2747         }
2748
2749         // Trim off common prefix
2750         while( count( $pieces ) && count( $against )
2751                 && $pieces[0] == $against[0] ) {
2752                 array_shift( $pieces );
2753                 array_shift( $against );
2754         }
2755
2756         // relative dots to bump us to the parent
2757         while( count( $against ) ) {
2758                 array_unshift( $pieces, '..' );
2759                 array_shift( $against );
2760         }
2761
2762         array_push( $pieces, wfBaseName( $path ) );
2763
2764         return implode( DIRECTORY_SEPARATOR, $pieces );
2765 }
2766
2767 /**
2768  * parse_url() work-alike, but non-broken.  Differences:
2769  *
2770  * 1) Does not raise warnings on bad URLs (just returns false)
2771  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2772  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2773  *
2774  * @param $url String: a URL to parse
2775  * @return Array: bits of the URL in an associative array, per PHP docs
2776  */
2777 function wfParseUrl( $url ) {
2778         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2779         wfSuppressWarnings();
2780         $bits = parse_url( $url );
2781         wfRestoreWarnings();
2782         if ( !$bits ) {
2783                 return false;
2784         }
2785
2786         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2787         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2788                 $bits['delimiter'] = '://';
2789         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2790                 $bits['delimiter'] = ':';
2791                 // parse_url detects for news: and mailto: the host part of an url as path
2792                 // We have to correct this wrong detection
2793                 if ( isset( $bits['path'] ) ) {
2794                         $bits['host'] = $bits['path'];
2795                         $bits['path'] = '';
2796                 }
2797         } else {
2798                 return false;
2799         }
2800
2801         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
2802         if ( !isset( $bits['host'] ) ) {
2803                 $bits['host'] = '';
2804
2805                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
2806                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
2807                         $bits['path'] = '/' . $bits['path'];
2808                 }
2809         }
2810         return $bits;
2811 }
2812
2813 /**
2814  * Make a URL index, appropriate for the el_index field of externallinks.
2815  *
2816  * @param $url String
2817  * @return String
2818  */
2819 function wfMakeUrlIndex( $url ) {
2820         $bits = wfParseUrl( $url );
2821
2822         // Reverse the labels in the hostname, convert to lower case
2823         // For emails reverse domainpart only
2824         if ( $bits['scheme'] == 'mailto' ) {
2825                 $mailparts = explode( '@', $bits['host'], 2 );
2826                 if ( count( $mailparts ) === 2 ) {
2827                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2828                 } else {
2829                         // No domain specified, don't mangle it
2830                         $domainpart = '';
2831                 }
2832                 $reversedHost = $domainpart . '@' . $mailparts[0];
2833         } else {
2834                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2835         }
2836         // Add an extra dot to the end
2837         // Why? Is it in wrong place in mailto links?
2838         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2839                 $reversedHost .= '.';
2840         }
2841         // Reconstruct the pseudo-URL
2842         $prot = $bits['scheme'];
2843         $index = $prot . $bits['delimiter'] . $reversedHost;
2844         // Leave out user and password. Add the port, path, query and fragment
2845         if ( isset( $bits['port'] ) ) {
2846                 $index .= ':' . $bits['port'];
2847         }
2848         if ( isset( $bits['path'] ) ) {
2849                 $index .= $bits['path'];
2850         } else {
2851                 $index .= '/';
2852         }
2853         if ( isset( $bits['query'] ) ) {
2854                 $index .= '?' . $bits['query'];
2855         }
2856         if ( isset( $bits['fragment'] ) ) {
2857                 $index .= '#' . $bits['fragment'];
2858         }
2859         return $index;
2860 }
2861
2862 /**
2863  * Do any deferred updates and clear the list
2864  *
2865  * @param $commit String: set to 'commit' to commit after every update to
2866  *                prevent lock contention
2867  */
2868 function wfDoUpdates( $commit = '' ) {
2869         global $wgDeferredUpdateList;
2870
2871         wfProfileIn( __METHOD__ );
2872
2873         // No need to get master connections in case of empty updates array
2874         if ( !count( $wgDeferredUpdateList ) ) {
2875                 wfProfileOut( __METHOD__ );
2876                 return;
2877         }
2878
2879         $doCommit = $commit == 'commit';
2880         if ( $doCommit ) {
2881                 $dbw = wfGetDB( DB_MASTER );
2882         }
2883
2884         foreach ( $wgDeferredUpdateList as $update ) {
2885                 $update->doUpdate();
2886
2887                 if ( $doCommit && $dbw->trxLevel() ) {
2888                         $dbw->commit();
2889                 }
2890         }
2891
2892         $wgDeferredUpdateList = array();
2893         wfProfileOut( __METHOD__ );
2894 }
2895
2896 /**
2897  * Convert an arbitrarily-long digit string from one numeric base
2898  * to another, optionally zero-padding to a minimum column width.
2899  *
2900  * Supports base 2 through 36; digit values 10-36 are represented
2901  * as lowercase letters a-z. Input is case-insensitive.
2902  *
2903  * @param $input String: of digits
2904  * @param $sourceBase Integer: 2-36
2905  * @param $destBase Integer: 2-36
2906  * @param $pad Integer: 1 or greater
2907  * @param $lowercase Boolean
2908  * @return String or false on invalid input
2909  */
2910 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2911         $input = strval( $input );
2912         if( $sourceBase < 2 ||
2913                 $sourceBase > 36 ||
2914                 $destBase < 2 ||
2915                 $destBase > 36 ||
2916                 $pad < 1 ||
2917                 $sourceBase != intval( $sourceBase ) ||
2918                 $destBase != intval( $destBase ) ||
2919                 $pad != intval( $pad ) ||
2920                 !is_string( $input ) ||
2921                 $input == '' ) {
2922                 return false;
2923         }
2924         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2925         $inDigits = array();
2926         $outChars = '';
2927
2928         // Decode and validate input string
2929         $input = strtolower( $input );
2930         for( $i = 0; $i < strlen( $input ); $i++ ) {
2931                 $n = strpos( $digitChars, $input[$i] );
2932                 if( $n === false || $n > $sourceBase ) {
2933                         return false;
2934                 }
2935                 $inDigits[] = $n;
2936         }
2937
2938         // Iterate over the input, modulo-ing out an output digit
2939         // at a time until input is gone.
2940         while( count( $inDigits ) ) {
2941                 $work = 0;
2942                 $workDigits = array();
2943
2944                 // Long division...
2945                 foreach( $inDigits as $digit ) {
2946                         $work *= $sourceBase;
2947                         $work += $digit;
2948
2949                         if( $work < $destBase ) {
2950                                 // Gonna need to pull another digit.
2951                                 if( count( $workDigits ) ) {
2952                                         // Avoid zero-padding; this lets us find
2953                                         // the end of the input very easily when
2954                                         // length drops to zero.
2955                                         $workDigits[] = 0;
2956                                 }
2957                         } else {
2958                                 // Finally! Actual division!
2959                                 $workDigits[] = intval( $work / $destBase );
2960
2961                                 // Isn't it annoying that most programming languages
2962                                 // don't have a single divide-and-remainder operator,
2963                                 // even though the CPU implements it that way?
2964                                 $work = $work % $destBase;
2965                         }
2966                 }
2967
2968                 // All that division leaves us with a remainder,
2969                 // which is conveniently our next output digit.
2970                 $outChars .= $digitChars[$work];
2971
2972                 // And we continue!
2973                 $inDigits = $workDigits;
2974         }
2975
2976         while( strlen( $outChars ) < $pad ) {
2977                 $outChars .= '0';
2978         }
2979
2980         return strrev( $outChars );
2981 }
2982
2983 /**
2984  * Create an object with a given name and an array of construct parameters
2985  *
2986  * @param $name String
2987  * @param $p Array: parameters
2988  * @deprecated since 1.18, warnings in 1.19, removal in 1.20
2989  */
2990 function wfCreateObject( $name, $p ) {
2991         wfDeprecated( __FUNCTION__ );
2992         return MWFunction::newObj( $name, $p );
2993 }
2994
2995 function wfHttpOnlySafe() {
2996         global $wgHttpOnlyBlacklist;
2997
2998         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2999                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3000                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3001                                 return false;
3002                         }
3003                 }
3004         }
3005
3006         return true;
3007 }
3008
3009 /**
3010  * Initialise php session
3011  *
3012  * @param $sessionId Bool
3013  */
3014 function wfSetupSession( $sessionId = false ) {
3015         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3016                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3017         if( $wgSessionsInMemcached ) {
3018                 if ( !defined( 'MW_COMPILED' ) ) {
3019                         global $IP;
3020                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3021                 }
3022                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3023                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3024
3025                 // It's necessary to register a shutdown function to call session_write_close(),
3026                 // because by the time the request shutdown function for the session module is
3027                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3028                 // this way are called before object destruction.
3029                 register_shutdown_function( 'memsess_write_close' );
3030         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3031                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3032                 # hasn't already been set to the desired value (that causes errors)
3033                 ini_set( 'session.save_handler', $wgSessionHandler );
3034         }
3035         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3036         wfDebugLog( 'cookie',
3037                 'session_set_cookie_params: "' . implode( '", "',
3038                         array(
3039                                 0,
3040                                 $wgCookiePath,
3041                                 $wgCookieDomain,
3042                                 $wgCookieSecure,
3043                                 $httpOnlySafe ) ) . '"' );
3044         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3045         session_cache_limiter( 'private, must-revalidate' );
3046         if ( $sessionId ) {
3047                 session_id( $sessionId );
3048         }
3049         wfSuppressWarnings();
3050         session_start();
3051         wfRestoreWarnings();
3052 }
3053
3054 /**
3055  * Get an object from the precompiled serialized directory
3056  *
3057  * @param $name String
3058  * @return Mixed: the variable on success, false on failure
3059  */
3060 function wfGetPrecompiledData( $name ) {
3061         global $IP;
3062
3063         $file = "$IP/serialized/$name";
3064         if ( file_exists( $file ) ) {
3065                 $blob = file_get_contents( $file );
3066                 if ( $blob ) {
3067                         return unserialize( $blob );
3068                 }
3069         }
3070         return false;
3071 }
3072
3073 /**
3074  * Get a cache key
3075  *
3076  * @param varargs
3077  * @return String
3078  */
3079 function wfMemcKey( /*... */ ) {
3080         $args = func_get_args();
3081         $key = wfWikiID() . ':' . implode( ':', $args );
3082         $key = str_replace( ' ', '_', $key );
3083         return $key;
3084 }
3085
3086 /**
3087  * Get a cache key for a foreign DB
3088  *
3089  * @param $db String
3090  * @param $prefix String
3091  * @param varargs String
3092  * @return String
3093  */
3094 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3095         $args = array_slice( func_get_args(), 2 );
3096         if ( $prefix ) {
3097                 $key = "$db-$prefix:" . implode( ':', $args );
3098         } else {
3099                 $key = $db . ':' . implode( ':', $args );
3100         }
3101         return $key;
3102 }
3103
3104 /**
3105  * Get an ASCII string identifying this wiki
3106  * This is used as a prefix in memcached keys
3107  *
3108  * @return String
3109  */
3110 function wfWikiID() {
3111         global $wgDBprefix, $wgDBname;
3112         if ( $wgDBprefix ) {
3113                 return "$wgDBname-$wgDBprefix";
3114         } else {
3115                 return $wgDBname;
3116         }
3117 }
3118
3119 /**
3120  * Split a wiki ID into DB name and table prefix
3121  *
3122  * @param $wiki String
3123  * @param $bits String
3124  */
3125 function wfSplitWikiID( $wiki ) {
3126         $bits = explode( '-', $wiki, 2 );
3127         if ( count( $bits ) < 2 ) {
3128                 $bits[] = '';
3129         }
3130         return $bits;
3131 }
3132
3133 /**
3134  * Get a Database object.
3135  *
3136  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3137  *            master (for write queries), DB_SLAVE for potentially lagged read
3138  *            queries, or an integer >= 0 for a particular server.
3139  *
3140  * @param $groups Mixed: query groups. An array of group names that this query
3141  *                belongs to. May contain a single string if the query is only
3142  *                in one group.
3143  *
3144  * @param $wiki String: the wiki ID, or false for the current wiki
3145  *
3146  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3147  * will always return the same object, unless the underlying connection or load
3148  * balancer is manually destroyed.
3149  *
3150  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3151  * updater to ensure that a proper database is being updated.
3152  *
3153  * @return DatabaseBase
3154  */
3155 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3156         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3157 }
3158
3159 /**
3160  * Get a load balancer object.
3161  *
3162  * @param $wiki String: wiki ID, or false for the current wiki
3163  * @return LoadBalancer
3164  */
3165 function wfGetLB( $wiki = false ) {
3166         return wfGetLBFactory()->getMainLB( $wiki );
3167 }
3168
3169 /**
3170  * Get the load balancer factory object
3171  *
3172  * @return LBFactory
3173  */
3174 function &wfGetLBFactory() {
3175         return LBFactory::singleton();
3176 }
3177
3178 /**
3179  * Find a file.
3180  * Shortcut for RepoGroup::singleton()->findFile()
3181  *
3182  * @param $title String or Title object
3183  * @param $options Associative array of options:
3184  *     time:           requested time for an archived image, or false for the
3185  *                     current version. An image object will be returned which was
3186  *                     created at the specified time.
3187  *
3188  *     ignoreRedirect: If true, do not follow file redirects
3189  *
3190  *     private:        If true, return restricted (deleted) files if the current
3191  *                     user is allowed to view them. Otherwise, such files will not
3192  *                     be found.
3193  *
3194  *     bypassCache:    If true, do not use the process-local cache of File objects
3195  *
3196  * @return File, or false if the file does not exist
3197  */
3198 function wfFindFile( $title, $options = array() ) {
3199         return RepoGroup::singleton()->findFile( $title, $options );
3200 }
3201
3202 /**
3203  * Get an object referring to a locally registered file.
3204  * Returns a valid placeholder object if the file does not exist.
3205  *
3206  * @param $title Title or String
3207  * @return File, or null if passed an invalid Title
3208  */
3209 function wfLocalFile( $title ) {
3210         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3211 }
3212
3213 /**
3214  * Should low-performance queries be disabled?
3215  *
3216  * @return Boolean
3217  * @codeCoverageIgnore
3218  */
3219 function wfQueriesMustScale() {
3220         global $wgMiserMode;
3221         return $wgMiserMode
3222                 || ( SiteStats::pages() > 100000
3223                 && SiteStats::edits() > 1000000
3224                 && SiteStats::users() > 10000 );
3225 }
3226
3227 /**
3228  * Get the path to a specified script file, respecting file
3229  * extensions; this is a wrapper around $wgScriptExtension etc.
3230  *
3231  * @param $script String: script filename, sans extension
3232  * @return String
3233  */
3234 function wfScript( $script = 'index' ) {
3235         global $wgScriptPath, $wgScriptExtension;
3236         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3237 }
3238
3239 /**
3240  * Get the script URL.
3241  *
3242  * @return script URL
3243  */
3244 function wfGetScriptUrl() {
3245         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3246                 #
3247                 # as it was called, minus the query string.
3248                 #
3249                 # Some sites use Apache rewrite rules to handle subdomains,
3250                 # and have PHP set up in a weird way that causes PHP_SELF
3251                 # to contain the rewritten URL instead of the one that the
3252                 # outside world sees.
3253                 #
3254                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3255                 # provides containing the "before" URL.
3256                 return $_SERVER['SCRIPT_NAME'];
3257         } else {
3258                 return $_SERVER['URL'];
3259         }
3260 }
3261
3262 /**
3263  * Convenience function converts boolean values into "true"
3264  * or "false" (string) values
3265  *
3266  * @param $value Boolean
3267  * @return String
3268  */
3269 function wfBoolToStr( $value ) {
3270         return $value ? 'true' : 'false';
3271 }
3272
3273 /**
3274  * Load an extension messages file
3275  *
3276  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3277  * @codeCoverageIgnore
3278  */
3279 function wfLoadExtensionMessages() {
3280         wfDeprecated( __FUNCTION__ );
3281 }
3282
3283 /**
3284  * Get a platform-independent path to the null file, e.g. /dev/null
3285  *
3286  * @return string
3287  */
3288 function wfGetNull() {
3289         return wfIsWindows()
3290                 ? 'NUL'
3291                 : '/dev/null';
3292 }
3293
3294 /**
3295  * Throws a warning that $function is deprecated
3296  *
3297  * @param $function String
3298  * @return null
3299  */
3300 function wfDeprecated( $function ) {
3301         static $functionsWarned = array();
3302         if ( !isset( $functionsWarned[$function] ) ) {
3303                 $functionsWarned[$function] = true;
3304                 wfWarn( "Use of $function is deprecated.", 2 );
3305         }
3306 }
3307
3308 /**
3309  * Send a warning either to the debug log or in a PHP error depending on
3310  * $wgDevelopmentWarnings
3311  *
3312  * @param $msg String: message to send
3313  * @param $callerOffset Integer: number of items to go back in the backtrace to
3314  *        find the correct caller (1 = function calling wfWarn, ...)
3315  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3316  *        is true
3317  */
3318 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3319         global $wgDevelopmentWarnings;
3320
3321         $callers = wfDebugBacktrace();
3322         if ( isset( $callers[$callerOffset + 1] ) ) {
3323                 $callerfunc = $callers[$callerOffset + 1];
3324                 $callerfile = $callers[$callerOffset];
3325                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3326                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3327                 } else {
3328                         $file = '(internal function)';
3329                 }
3330                 $func = '';
3331                 if ( isset( $callerfunc['class'] ) ) {
3332                         $func .= $callerfunc['class'] . '::';
3333                 }
3334                 if ( isset( $callerfunc['function'] ) ) {
3335                         $func .= $callerfunc['function'];
3336                 }
3337                 $msg .= " [Called from $func in $file]";
3338         }
3339
3340         if ( $wgDevelopmentWarnings ) {
3341                 trigger_error( $msg, $level );
3342         } else {
3343                 wfDebug( "$msg\n" );
3344         }
3345 }
3346
3347 /**
3348  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3349  * and waiting for it to go down, this waits for the slaves to catch up to the
3350  * master position. Use this when updating very large numbers of rows, as
3351  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3352  * a no-op if there are no slaves.
3353  *
3354  * @param $maxLag Integer (deprecated)
3355  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3356  * @return null
3357  */
3358 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3359         $lb = wfGetLB( $wiki );
3360         // bug 27975 - Don't try to wait for slaves if there are none
3361         // Prevents permission error when getting master position
3362         if ( $lb->getServerCount() > 1 ) {
3363                 $dbw = $lb->getConnection( DB_MASTER );
3364                 $pos = $dbw->getMasterPos();
3365                 $lb->waitForAll( $pos );
3366         }
3367 }
3368
3369 /**
3370  * Used to be used for outputting text in the installer/updater
3371  * @deprecated since 1.18, warnings in 1.19, remove in 1.20
3372  */
3373 function wfOut( $s ) {
3374         wfDeprecated( __METHOD__ );
3375         global $wgCommandLineMode;
3376         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3377                 echo $s;
3378         } else {
3379                 echo htmlspecialchars( $s );
3380         }
3381         flush();
3382 }
3383
3384 /**
3385  * Count down from $n to zero on the terminal, with a one-second pause
3386  * between showing each number. For use in command-line scripts.
3387  * @codeCoverageIgnore
3388  */
3389 function wfCountDown( $n ) {
3390         for ( $i = $n; $i >= 0; $i-- ) {
3391                 if ( $i != $n ) {
3392                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3393                 }
3394                 echo $i;
3395                 flush();
3396                 if ( $i ) {
3397                         sleep( 1 );
3398                 }
3399         }
3400         echo "\n";
3401 }
3402
3403 /**
3404  * Generate a random 32-character hexadecimal token.
3405  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3406  *              characters before hashing.
3407  * @return string
3408  * @codeCoverageIgnore
3409  */
3410 function wfGenerateToken( $salt = '' ) {
3411         $salt = serialize( $salt );
3412         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3413 }
3414
3415 /**
3416  * Replace all invalid characters with -
3417  *
3418  * @param $name Mixed: filename to process
3419  * @return String
3420  */
3421 function wfStripIllegalFilenameChars( $name ) {
3422         global $wgIllegalFileChars;
3423         $name = wfBaseName( $name );
3424         $name = preg_replace(
3425                 "/[^" . Title::legalChars() . "]" .
3426                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3427                         "/",
3428                 '-',
3429                 $name
3430         );
3431         return $name;
3432 }
3433
3434 /**
3435  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3436  *
3437  * @return Integer value memory was set to.
3438  */
3439 function wfMemoryLimit() {
3440         global $wgMemoryLimit;
3441         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3442         if( $memlimit != -1 ) {
3443                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3444                 if( $conflimit == -1 ) {
3445                         wfDebug( "Removing PHP's memory limit\n" );
3446                         wfSuppressWarnings();
3447                         ini_set( 'memory_limit', $conflimit );
3448                         wfRestoreWarnings();
3449                         return $conflimit;
3450                 } elseif ( $conflimit > $memlimit ) {
3451                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3452                         wfSuppressWarnings();
3453                         ini_set( 'memory_limit', $conflimit );
3454                         wfRestoreWarnings();
3455                         return $conflimit;
3456                 }
3457         }
3458         return $memlimit;
3459 }
3460
3461 /**
3462  * Converts shorthand byte notation to integer form
3463  *
3464  * @param $string String
3465  * @return Integer
3466  */
3467 function wfShorthandToInteger( $string = '' ) {
3468         $string = trim( $string );
3469         if( $string === '' ) {
3470                 return -1;
3471         }
3472         $last = $string[strlen( $string ) - 1];
3473         $val = intval( $string );
3474         switch( $last ) {
3475                 case 'g':
3476                 case 'G':
3477                         $val *= 1024;
3478                         // break intentionally missing
3479                 case 'm':
3480                 case 'M':
3481                         $val *= 1024;
3482                         // break intentionally missing
3483                 case 'k':
3484                 case 'K':
3485                         $val *= 1024;
3486         }
3487
3488         return $val;
3489 }
3490
3491 /**
3492  * Get the normalised IETF language tag
3493  * See unit test for examples.
3494  *
3495  * @param $code String: The language code.
3496  * @return $langCode String: The language code which complying with BCP 47 standards.
3497  */
3498 function wfBCP47( $code ) {
3499         $codeSegment = explode( '-', $code );
3500         $codeBCP = array();
3501         foreach ( $codeSegment as $segNo => $seg ) {
3502                 if ( count( $codeSegment ) > 0 ) {
3503                         // when previous segment is x, it is a private segment and should be lc
3504                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3505                                 $codeBCP[$segNo] = strtolower( $seg );
3506                         // ISO 3166 country code
3507                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3508                                 $codeBCP[$segNo] = strtoupper( $seg );
3509                         // ISO 15924 script code
3510                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3511                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3512                         // Use lowercase for other cases
3513                         } else {
3514                                 $codeBCP[$segNo] = strtolower( $seg );
3515                         }
3516                 } else {
3517                 // Use lowercase for single segment
3518                         $codeBCP[$segNo] = strtolower( $seg );
3519                 }
3520         }
3521         $langCode = implode( '-', $codeBCP );
3522         return $langCode;
3523 }
3524
3525 /**
3526  * Get a cache object.
3527  *
3528  * @param integer $inputType Cache type, one the the CACHE_* constants.
3529  * @return BagOStuff
3530  */
3531 function wfGetCache( $inputType ) {
3532         return ObjectCache::getInstance( $inputType );
3533 }
3534
3535 /**
3536  * Get the main cache object
3537  *
3538  * @return BagOStuff
3539  */
3540 function wfGetMainCache() {
3541         global $wgMainCacheType;
3542         return ObjectCache::getInstance( $wgMainCacheType );
3543 }
3544
3545 /**
3546  * Get the cache object used by the message cache
3547  *
3548  * @return BagOStuff
3549  */
3550 function wfGetMessageCacheStorage() {
3551         global $wgMessageCacheType;
3552         return ObjectCache::getInstance( $wgMessageCacheType );
3553 }
3554
3555 /**
3556  * Get the cache object used by the parser cache
3557  *
3558  * @return BagOStuff
3559  */
3560 function wfGetParserCacheStorage() {
3561         global $wgParserCacheType;
3562         return ObjectCache::getInstance( $wgParserCacheType );
3563 }
3564
3565 /**
3566  * Call hook functions defined in $wgHooks
3567  *
3568  * @param $event String: event name
3569  * @param $args Array: parameters passed to hook functions
3570  * @return Boolean
3571  */
3572 function wfRunHooks( $event, $args = array() ) {
3573         return Hooks::run( $event, $args );
3574 }