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 require_once dirname( __FILE__ ) . '/normal/UtfNormalUtil.php';
  12
  13 // Hide compatibility functions from Doxygen
  14 /// @cond
  15
  16 /**
  17  * Compatibility functions
  18  *
  19  * We support PHP 5.1.x and up.
  20  * Re-implementations of newer functions or functions in non-standard
  21  * PHP extensions may be included here.
  22  */
  23 if( !function_exists( 'iconv' ) ) {
  24         # iconv support is not in the default configuration and so may not be present.
  25         # Assume will only ever use utf-8 and iso-8859-1.
  26         # This will *not* work in all circumstances.
  27         function iconv( $from, $to, $string ) {
  28                 if ( substr( $to, -8 ) == '//IGNORE' ) {
  29                         $to = substr( $to, 0, strlen( $to ) - 8 );
  30                 }
  31                 if( strcasecmp( $from, $to ) == 0 ) {
  32                         return $string;
  33                 }
  34                 if( strcasecmp( $from, 'utf-8' ) == 0 ) {
  35                         return utf8_decode( $string );
  36                 }
  37                 if( strcasecmp( $to, 'utf-8' ) == 0 ) {
  38                         return utf8_encode( $string );
  39                 }
  40                 return $string;
  41         }
  42 }
  43
  44 if ( !function_exists( 'mb_substr' ) ) {
  45         /**
  46          * Fallback implementation for mb_substr, hardcoded to UTF-8.
  47          * Attempts to be at least _moderately_ efficient; best optimized
  48          * for relatively small offset and count values -- about 5x slower
  49          * than native mb_string in my testing.
  50          *
  51          * Larger offsets are still fairly efficient for Latin text, but
  52          * can be up to 100x slower than native if the text is heavily
  53          * multibyte and we have to slog through a few hundred kb.
  54          */
  55         function mb_substr( $str, $start, $count='end' ) {
  56                 if( $start != 0 ) {
  57                         $split = mb_substr_split_unicode( $str, intval( $start ) );
  58                         $str = substr( $str, $split );
  59                 }
  60
  61                 if( $count !== 'end' ) {
  62                         $split = mb_substr_split_unicode( $str, intval( $count ) );
  63                         $str = substr( $str, 0, $split );
  64                 }
  65
  66                 return $str;
  67         }
  68
  69         function mb_substr_split_unicode( $str, $splitPos ) {
  70                 if( $splitPos == 0 ) {
  71                         return 0;
  72                 }
  73
  74                 $byteLen = strlen( $str );
  75
  76                 if( $splitPos > 0 ) {
  77                         if( $splitPos > 256 ) {
  78                                 // Optimize large string offsets by skipping ahead N bytes.
  79                                 // This will cut out most of our slow time on Latin-based text,
  80                                 // and 1/2 to 1/3 on East European and Asian scripts.
  81                                 $bytePos = $splitPos;
  82                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  83                                         ++$bytePos;
  84                                 }
  85                                 $charPos = mb_strlen( substr( $str, 0, $bytePos ) );
  86                         } else {
  87                                 $charPos = 0;
  88                                 $bytePos = 0;
  89                         }
  90
  91                         while( $charPos++ < $splitPos ) {
  92                                 ++$bytePos;
  93                                 // Move past any tail bytes
  94                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  95                                         ++$bytePos;
  96                                 }
  97                         }
  98                 } else {
  99                         $splitPosX = $splitPos + 1;
 100                         $charPos = 0; // relative to end of string; we don't care about the actual char position here
 101                         $bytePos = $byteLen;
 102                         while( $bytePos > 0 && $charPos-- >= $splitPosX ) {
 103                                 --$bytePos;
 104                                 // Move past any tail bytes
 105                                 while ( $bytePos > 0 && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
 106                                         --$bytePos;
 107                                 }
 108                         }
 109                 }
 110
 111                 return $bytePos;
 112         }
 113 }
 114
 115 if ( !function_exists( 'mb_strlen' ) ) {
 116         /**
 117          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
 118          * @param string $str
 119          * @param string $enc optional encoding; ignored
 120          * @return int
 121          */
 122         function mb_strlen( $str, $enc = '' ) {
 123                 $counts = count_chars( $str );
 124                 $total = 0;
 125
 126                 // Count ASCII bytes
 127                 for( $i = 0; $i < 0x80; $i++ ) {
 128                         $total += $counts[$i];
 129                 }
 130
 131                 // Count multibyte sequence heads
 132                 for( $i = 0xc0; $i < 0xff; $i++ ) {
 133                         $total += $counts[$i];
 134                 }
 135                 return $total;
 136         }
 137 }
 138
 139
 140 if( !function_exists( 'mb_strpos' ) ) {
 141         /**
 142          * Fallback implementation of mb_strpos, hardcoded to UTF-8.
 143          * @param $haystack String
 144          * @param $needle String
 145          * @param $offset String: optional start position
 146          * @param $encoding String: optional encoding; ignored
 147          * @return int
 148          */
 149         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 150                 $needle = preg_quote( $needle, '/' );
 151
 152                 $ar = array();
 153                 preg_match( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 154
 155                 if( isset( $ar[0][1] ) ) {
 156                         return $ar[0][1];
 157                 } else {
 158                         return false;
 159                 }
 160         }
 161 }
 162
 163 if( !function_exists( 'mb_strrpos' ) ) {
 164         /**
 165          * Fallback implementation of mb_strrpos, hardcoded to UTF-8.
 166          * @param $haystack String
 167          * @param $needle String
 168          * @param $offset String: optional start position
 169          * @param $encoding String: optional encoding; ignored
 170          * @return int
 171          */
 172         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 173                 $needle = preg_quote( $needle, '/' );
 174
 175                 $ar = array();
 176                 preg_match_all( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 177
 178                 if( isset( $ar[0] ) && count( $ar[0] ) > 0 &&
 179                         isset( $ar[0][count( $ar[0] ) - 1][1] ) ) {
 180                         return $ar[0][count( $ar[0] ) - 1][1];
 181                 } else {
 182                         return false;
 183                 }
 184         }
 185 }
 186
 187 // Support for Wietse Venema's taint feature
 188 if ( !function_exists( 'istainted' ) ) {
 189         function istainted( $var ) {
 190                 return 0;
 191         }
 192         function taint( $var, $level = 0 ) {}
 193         function untaint( $var, $level = 0 ) {}
 194         define( 'TC_HTML', 1 );
 195         define( 'TC_SHELL', 1 );
 196         define( 'TC_MYSQL', 1 );
 197         define( 'TC_PCRE', 1 );
 198         define( 'TC_SELF', 1 );
 199 }
 200 /// @endcond
 201
 202
 203 /**
 204  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 205  */
 206 function wfArrayDiff2( $a, $b ) {
 207         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 208 }
 209 function wfArrayDiff2_cmp( $a, $b ) {
 210         if ( !is_array( $a ) ) {
 211                 return strcmp( $a, $b );
 212         } elseif ( count( $a ) !== count( $b ) ) {
 213                 return count( $a ) < count( $b ) ? -1 : 1;
 214         } else {
 215                 reset( $a );
 216                 reset( $b );
 217                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 218                         $cmp = strcmp( $valueA, $valueB );
 219                         if ( $cmp !== 0 ) {
 220                                 return $cmp;
 221                         }
 222                 }
 223                 return 0;
 224         }
 225 }
 226
 227 /**
 228  * Seed Mersenne Twister
 229  * No-op for compatibility; only necessary in PHP < 4.2.0
 230  * @deprecated. Remove in 1.18
 231  */
 232 function wfSeedRandom() {
 233         wfDeprecated(__FUNCTION__);
 234 }
 235
 236 /**
 237  * Get a random decimal value between 0 and 1, in a way
 238  * not likely to give duplicate values for any realistic
 239  * number of articles.
 240  *
 241  * @return string
 242  */
 243 function wfRandom() {
 244         # The maximum random value is "only" 2^31-1, so get two random
 245         # values to reduce the chance of dupes
 246         $max = mt_getrandmax() + 1;
 247         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 248                 / $max / $max, 12, '.', '' );
 249         return $rand;
 250 }
 251
 252 /**
 253  * We want some things to be included as literal characters in our title URLs
 254  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 255  * all of the following should be safe:
 256  *
 257  * ;:@&=$-_.+!*'(),
 258  *
 259  * But + is not safe because it's used to indicate a space; &= are only safe in
 260  * paths and not in queries (and we don't distinguish here); ' seems kind of
 261  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 262  * is reserved, we don't care.  So the list we unescape is:
 263  *
 264  * ;:@$!*(),/
 265  *
 266  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 267  * so no fancy : for IIS7.
 268  *
 269  * %2F in the page titles seems to fatally break for some reason.
 270  *
 271  * @param $s String:
 272  * @return string
 273 */
 274 function wfUrlencode( $s ) {
 275         static $needle;
 276         if ( is_null( $needle ) ) {
 277                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 278                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 279                         $needle[] = '%3A';
 280                 }
 281         }
 282
 283         $s = urlencode( $s );
 284         $s = str_ireplace(
 285                 $needle,
 286                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 287                 $s
 288         );
 289
 290         return $s;
 291 }
 292
 293 /**
 294  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 295  * In normal operation this is a NOP.
 296  *
 297  * Controlling globals:
 298  * $wgDebugLogFile - points to the log file
 299  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 300  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 301  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 302  *
 303  * @param $text String
 304  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 305  */
 306 function wfDebug( $text, $logonly = false ) {
 307         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 308         global $wgDebugLogPrefix, $wgShowDebug;
 309         static $recursion = 0;
 310
 311         static $cache = array(); // Cache of unoutputted messages
 312         $text = wfDebugTimer() . $text;
 313
 314         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 315         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 316                 return;
 317         }
 318
 319         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 320                 $cache[] = $text;
 321
 322                 if ( !isset( $wgOut ) ) {
 323                         return;
 324                 }
 325                 if ( !StubObject::isRealObject( $wgOut ) ) {
 326                         if ( $recursion ) {
 327                                 return;
 328                         }
 329                         $recursion++;
 330                         $wgOut->_unstub();
 331                         $recursion--;
 332                 }
 333
 334                 // add the message and possible cached ones to the output
 335                 array_map( array( $wgOut, 'debug' ), $cache );
 336                 $cache = array();
 337         }
 338         if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 339                 # Strip unprintables; they can switch terminal modes when binary data
 340                 # gets dumped, which is pretty annoying.
 341                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 342                 $text = $wgDebugLogPrefix . $text;
 343                 wfErrorLog( $text, $wgDebugLogFile );
 344         }
 345 }
 346
 347 function wfDebugTimer() {
 348         global $wgDebugTimestamps;
 349         if ( !$wgDebugTimestamps ) {
 350                 return '';
 351         }
 352         static $start = null;
 353
 354         if ( $start === null ) {
 355                 $start = microtime( true );
 356                 $prefix = "\n$start";
 357         } else {
 358                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 359         }
 360
 361         return $prefix . '  ';
 362 }
 363
 364 /**
 365  * Send a line giving PHP memory usage.
 366  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 367  */
 368 function wfDebugMem( $exact = false ) {
 369         $mem = memory_get_usage();
 370         if( !$exact ) {
 371                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 372         } else {
 373                 $mem .= ' bytes';
 374         }
 375         wfDebug( "Memory usage: $mem\n" );
 376 }
 377
 378 /**
 379  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 380  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 381  *
 382  * @param $logGroup String
 383  * @param $text String
 384  * @param $public Bool: whether to log the event in the public log if no private
 385  *                     log file is specified, (default true)
 386  */
 387 function wfDebugLog( $logGroup, $text, $public = true ) {
 388         global $wgDebugLogGroups, $wgShowHostnames;
 389         $text = trim( $text ) . "\n";
 390         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 391                 $time = wfTimestamp( TS_DB );
 392                 $wiki = wfWikiID();
 393                 if ( $wgShowHostnames ) {
 394                         $host = wfHostname();
 395                 } else {
 396                         $host = '';
 397                 }
 398                 wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 399         } elseif ( $public === true ) {
 400                 wfDebug( $text, true );
 401         }
 402 }
 403
 404 /**
 405  * Log for database errors
 406  * @param $text String: database error message.
 407  */
 408 function wfLogDBError( $text ) {
 409         global $wgDBerrorLog, $wgDBname;
 410         if ( $wgDBerrorLog ) {
 411                 $host = trim(`hostname`);
 412                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 413                 wfErrorLog( $text, $wgDBerrorLog );
 414         }
 415 }
 416
 417 /**
 418  * Log to a file without getting "file size exceeded" signals.
 419  *
 420  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 421  * send lines to the specified port, prefixed by the specified prefix and a space.
 422  */
 423 function wfErrorLog( $text, $file ) {
 424         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 425                 # Needs the sockets extension
 426                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 427                         // IPv6 bracketed host
 428                         $host = $m[2];
 429                         $port = intval( $m[3] );
 430                         $prefix = isset( $m[4] ) ? $m[4] : false;
 431                         $domain = AF_INET6;
 432                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 433                         $host = $m[2];
 434                         if ( !IP::isIPv4( $host ) ) {
 435                                 $host = gethostbyname( $host );
 436                         }
 437                         $port = intval( $m[3] );
 438                         $prefix = isset( $m[4] ) ? $m[4] : false;
 439                         $domain = AF_INET;
 440                 } else {
 441                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 442                 }
 443                 // Clean it up for the multiplexer
 444                 if ( strval( $prefix ) !== '' ) {
 445                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 446                         if ( substr( $text, -1 ) != "\n" ) {
 447                                 $text .= "\n";
 448                         }
 449                 }
 450
 451                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 452                 if ( !$sock ) {
 453                         return;
 454                 }
 455                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 456                 socket_close( $sock );
 457         } else {
 458                 wfSuppressWarnings();
 459                 $exists = file_exists( $file );
 460                 $size = $exists ? filesize( $file ) : false;
 461                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 462                         error_log( $text, 3, $file );
 463                 }
 464                 wfRestoreWarnings();
 465         }
 466 }
 467
 468 /**
 469  * @todo document
 470  */
 471 function wfLogProfilingData() {
 472         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 473         global $wgProfiler, $wgProfileLimit, $wgUser;
 474         # Profiling must actually be enabled...
 475         if( is_null( $wgProfiler ) ) {
 476                 return;
 477         }
 478         # Get total page request time
 479         $now = wfTime();
 480         $elapsed = $now - $wgRequestTime;
 481         # Only show pages that longer than $wgProfileLimit time (default is 0)
 482         if( $elapsed <= $wgProfileLimit ) {
 483                 return;
 484         }
 485         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 486         $forward = '';
 487         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 488                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 489         }
 490         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 491                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 492         }
 493         if( !empty( $_SERVER['HTTP_FROM'] ) ) {
 494                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 495         }
 496         if( $forward ) {
 497                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 498         }
 499         // Don't unstub $wgUser at this late stage just for statistics purposes
 500         // FIXME: We can detect some anons even if it is not loaded. See User::getId()
 501         if( $wgUser->mDataLoaded && $wgUser->isAnon() ) {
 502                 $forward .= ' anon';
 503         }
 504         $log = sprintf( "%s\t%04.3f\t%s\n",
 505                 gmdate( 'YmdHis' ), $elapsed,
 506                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 507         if ( $wgDebugLogFile != '' && ( $wgRequest->getVal( 'action' ) != 'raw' || $wgDebugRawPage ) ) {
 508                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 509         }
 510 }
 511
 512 /**
 513  * Check if the wiki read-only lock file is present. This can be used to lock
 514  * off editing functions, but doesn't guarantee that the database will not be
 515  * modified.
 516  * @return bool
 517  */
 518 function wfReadOnly() {
 519         global $wgReadOnlyFile, $wgReadOnly;
 520
 521         if ( !is_null( $wgReadOnly ) ) {
 522                 return (bool)$wgReadOnly;
 523         }
 524         if ( $wgReadOnlyFile == '' ) {
 525                 return false;
 526         }
 527         // Set $wgReadOnly for faster access next time
 528         if ( is_file( $wgReadOnlyFile ) ) {
 529                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 530         } else {
 531                 $wgReadOnly = false;
 532         }
 533         return (bool)$wgReadOnly;
 534 }
 535
 536 function wfReadOnlyReason() {
 537         global $wgReadOnly;
 538         wfReadOnly();
 539         return $wgReadOnly;
 540 }
 541
 542 /**
 543  * Return a Language object from $langcode
 544  * @param $langcode Mixed: either:
 545  *                  - a Language object
 546  *                  - code of the language to get the message for, if it is
 547  *                    a valid code create a language for that language, if
 548  *                    it is a string but not a valid code then make a basic
 549  *                    language object
 550  *                  - a boolean: if it's false then use the current users
 551  *                    language (as a fallback for the old parameter
 552  *                    functionality), or if it is true then use the wikis
 553  * @return Language object
 554  */
 555 function wfGetLangObj( $langcode = false ) {
 556         # Identify which language to get or create a language object for.
 557         # Using is_object here due to Stub objects.
 558         if( is_object( $langcode ) ) {
 559                 # Great, we already have the object (hopefully)!
 560                 return $langcode;
 561         }
 562
 563         global $wgContLang, $wgLanguageCode;
 564         if( $langcode === true || $langcode === $wgLanguageCode ) {
 565                 # $langcode is the language code of the wikis content language object.
 566                 # or it is a boolean and value is true
 567                 return $wgContLang;
 568         }
 569
 570         global $wgLang;
 571         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 572                 # $langcode is the language code of user language object.
 573                 # or it was a boolean and value is false
 574                 return $wgLang;
 575         }
 576
 577         $validCodes = array_keys( Language::getLanguageNames() );
 578         if( in_array( $langcode, $validCodes ) ) {
 579                 # $langcode corresponds to a valid language.
 580                 return Language::factory( $langcode );
 581         }
 582
 583         # $langcode is a string, but not a valid language code; use content language.
 584         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 585         return $wgContLang;
 586 }
 587
 588 /**
 589  * Use this instead of $wgContLang, when working with user interface.
 590  * User interface is currently hard coded according to wiki content language
 591  * in many ways, especially regarding to text direction. There is lots stuff
 592  * to fix, hence this function to keep the old behaviour unless the global
 593  * $wgBetterDirectionality is enabled (or removed when everything works).
 594  */
 595 function wfUILang() {
 596         global $wgBetterDirectionality;
 597         return wfGetLangObj( !$wgBetterDirectionality );
 598 }
 599
 600 /**
 601  * This is the new function for getting translated interface messages.
 602  * See the Message class for documentation how to use them.
 603  * The intention is that this function replaces all old wfMsg* functions.
 604  * @param $key \string Message key.
 605  * Varargs: normal message parameters.
 606  * @return \type{Message}
 607  * @since 1.17
 608  */
 609 function wfMessage( $key /*...*/) {
 610         $params = func_get_args();
 611         array_shift( $params );
 612         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 613                 $params = $params[0];
 614         }
 615         return new Message( $key, $params );
 616 }
 617
 618 /**
 619  * Get a message from anywhere, for the current user language.
 620  *
 621  * Use wfMsgForContent() instead if the message should NOT
 622  * change depending on the user preferences.
 623  *
 624  * @param $key String: lookup key for the message, usually
 625  *    defined in languages/Language.php
 626  *
 627  * This function also takes extra optional parameters (not
 628  * shown in the function definition), which can be used to
 629  * insert variable text into the predefined message.
 630  */
 631 function wfMsg( $key ) {
 632         $args = func_get_args();
 633         array_shift( $args );
 634         return wfMsgReal( $key, $args, true );
 635 }
 636
 637 /**
 638  * Same as above except doesn't transform the message
 639  */
 640 function wfMsgNoTrans( $key ) {
 641         $args = func_get_args();
 642         array_shift( $args );
 643         return wfMsgReal( $key, $args, true, false, false );
 644 }
 645
 646 /**
 647  * Get a message from anywhere, for the current global language
 648  * set with $wgLanguageCode.
 649  *
 650  * Use this if the message should NOT change dependent on the
 651  * language set in the user's preferences. This is the case for
 652  * most text written into logs, as well as link targets (such as
 653  * the name of the copyright policy page). Link titles, on the
 654  * other hand, should be shown in the UI language.
 655  *
 656  * Note that MediaWiki allows users to change the user interface
 657  * language in their preferences, but a single installation
 658  * typically only contains content in one language.
 659  *
 660  * Be wary of this distinction: If you use wfMsg() where you should
 661  * use wfMsgForContent(), a user of the software may have to
 662  * customize potentially hundreds of messages in
 663  * order to, e.g., fix a link in every possible language.
 664  *
 665  * @param $key String: lookup key for the message, usually
 666  *    defined in languages/Language.php
 667  */
 668 function wfMsgForContent( $key ) {
 669         global $wgForceUIMsgAsContentMsg;
 670         $args = func_get_args();
 671         array_shift( $args );
 672         $forcontent = true;
 673         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 674                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 675         {
 676                 $forcontent = false;
 677         }
 678         return wfMsgReal( $key, $args, true, $forcontent );
 679 }
 680
 681 /**
 682  * Same as above except doesn't transform the message
 683  */
 684 function wfMsgForContentNoTrans( $key ) {
 685         global $wgForceUIMsgAsContentMsg;
 686         $args = func_get_args();
 687         array_shift( $args );
 688         $forcontent = true;
 689         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 690                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 691         {
 692                 $forcontent = false;
 693         }
 694         return wfMsgReal( $key, $args, true, $forcontent, false );
 695 }
 696
 697 /**
 698  * Get a message from the language file, for the UI elements
 699  */
 700 function wfMsgNoDB( $key ) {
 701         $args = func_get_args();
 702         array_shift( $args );
 703         return wfMsgReal( $key, $args, false );
 704 }
 705
 706 /**
 707  * Get a message from the language file, for the content
 708  */
 709 function wfMsgNoDBForContent( $key ) {
 710         global $wgForceUIMsgAsContentMsg;
 711         $args = func_get_args();
 712         array_shift( $args );
 713         $forcontent = true;
 714         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 715                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 716         {
 717                 $forcontent = false;
 718         }
 719         return wfMsgReal( $key, $args, false, $forcontent );
 720 }
 721
 722
 723 /**
 724  * Really get a message
 725  * @param $key String: key to get.
 726  * @param $args
 727  * @param $useDB Boolean
 728  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 729  * @param $transform Boolean: Whether or not to transform the message.
 730  * @return String: the requested message.
 731  */
 732 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 733         wfProfileIn( __METHOD__ );
 734         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 735         $message = wfMsgReplaceArgs( $message, $args );
 736         wfProfileOut( __METHOD__ );
 737         return $message;
 738 }
 739
 740 /**
 741  * This function provides the message source for messages to be edited which are *not* stored in the database.
 742  * @param $key String:
 743  */
 744 function wfMsgWeirdKey( $key ) {
 745         $source = wfMsgGetKey( $key, false, true, false );
 746         if ( wfEmptyMsg( $key, $source ) ) {
 747                 return '';
 748         } else {
 749                 return $source;
 750         }
 751 }
 752
 753 /**
 754  * Fetch a message string value, but don't replace any keys yet.
 755  * @param $key String
 756  * @param $useDB Bool
 757  * @param $langCode String: Code of the language to get the message for, or
 758  *                  behaves as a content language switch if it is a boolean.
 759  * @param $transform Boolean: whether to parse magic words, etc.
 760  * @return string
 761  */
 762 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 763         global $wgMessageCache;
 764
 765         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 766
 767         if ( !is_object( $wgMessageCache ) ) {
 768                 throw new MWException( 'Trying to get message before message cache is initialised' );
 769         }
 770
 771         $message = $wgMessageCache->get( $key, $useDB, $langCode );
 772         if( $message === false ) {
 773                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 774         } elseif ( $transform ) {
 775                 $message = $wgMessageCache->transform( $message );
 776         }
 777         return $message;
 778 }
 779
 780 /**
 781  * Replace message parameter keys on the given formatted output.
 782  *
 783  * @param $message String
 784  * @param $args Array
 785  * @return string
 786  * @private
 787  */
 788 function wfMsgReplaceArgs( $message, $args ) {
 789         # Fix windows line-endings
 790         # Some messages are split with explode("\n", $msg)
 791         $message = str_replace( "\r", '', $message );
 792
 793         // Replace arguments
 794         if ( count( $args ) ) {
 795                 if ( is_array( $args[0] ) ) {
 796                         $args = array_values( $args[0] );
 797                 }
 798                 $replacementKeys = array();
 799                 foreach( $args as $n => $param ) {
 800                         $replacementKeys['$' . ( $n + 1 )] = $param;
 801                 }
 802                 $message = strtr( $message, $replacementKeys );
 803         }
 804
 805         return $message;
 806 }
 807
 808 /**
 809  * Return an HTML-escaped version of a message.
 810  * Parameter replacements, if any, are done *after* the HTML-escaping,
 811  * so parameters may contain HTML (eg links or form controls). Be sure
 812  * to pre-escape them if you really do want plaintext, or just wrap
 813  * the whole thing in htmlspecialchars().
 814  *
 815  * @param $key String
 816  * @param string ... parameters
 817  * @return string
 818  */
 819 function wfMsgHtml( $key ) {
 820         $args = func_get_args();
 821         array_shift( $args );
 822         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 823 }
 824
 825 /**
 826  * Return an HTML version of message
 827  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 828  * so parameters may contain HTML (eg links or form controls). Be sure
 829  * to pre-escape them if you really do want plaintext, or just wrap
 830  * the whole thing in htmlspecialchars().
 831  *
 832  * @param $key String
 833  * @param string ... parameters
 834  * @return string
 835  */
 836 function wfMsgWikiHtml( $key ) {
 837         global $wgOut;
 838         $args = func_get_args();
 839         array_shift( $args );
 840         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 841 }
 842
 843 /**
 844  * Returns message in the requested format
 845  * @param $key String: key of the message
 846  * @param $options Array: processing rules. Can take the following options:
 847  *   <i>parse</i>: parses wikitext to HTML
 848  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 849  *       p's added by parser or tidy
 850  *   <i>escape</i>: filters message through htmlspecialchars
 851  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 852  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 853  *   <i>parsemag</i>: transform the message using magic phrases
 854  *   <i>content</i>: fetch message for content language instead of interface
 855  * Also can accept a single associative argument, of the form 'language' => 'xx':
 856  *   <i>language</i>: Language object or language code to fetch message for
 857  *       (overriden by <i>content</i>), its behaviour with parse, parseinline
 858  *       and parsemag is undefined.
 859  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 860  */
 861 function wfMsgExt( $key, $options ) {
 862         global $wgOut;
 863
 864         $args = func_get_args();
 865         array_shift( $args );
 866         array_shift( $args );
 867         $options = (array)$options;
 868
 869         foreach( $options as $arrayKey => $option ) {
 870                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 871                         # An unknown index, neither numeric nor "language"
 872                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 873                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 874                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 875                 'replaceafter', 'parsemag', 'content' ) ) ) {
 876                         # A numeric index with unknown value
 877                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 878                 }
 879         }
 880
 881         if( in_array( 'content', $options, true ) ) {
 882                 $forContent = true;
 883                 $langCode = true;
 884         } elseif( array_key_exists( 'language', $options ) ) {
 885                 $forContent = false;
 886                 $langCode = wfGetLangObj( $options['language'] );
 887         } else {
 888                 $forContent = false;
 889                 $langCode = false;
 890         }
 891
 892         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 893
 894         if( !in_array( 'replaceafter', $options, true ) ) {
 895                 $string = wfMsgReplaceArgs( $string, $args );
 896         }
 897
 898         if( in_array( 'parse', $options, true ) ) {
 899                 $string = $wgOut->parse( $string, true, !$forContent );
 900         } elseif ( in_array( 'parseinline', $options, true ) ) {
 901                 $string = $wgOut->parse( $string, true, !$forContent );
 902                 $m = array();
 903                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 904                         $string = $m[1];
 905                 }
 906         } elseif ( in_array( 'parsemag', $options, true ) ) {
 907                 global $wgMessageCache;
 908                 if ( isset( $wgMessageCache ) ) {
 909                         $string = $wgMessageCache->transform( $string,
 910                                 !$forContent,
 911                                 is_object( $langCode ) ? $langCode : null );
 912                 }
 913         }
 914
 915         if ( in_array( 'escape', $options, true ) ) {
 916                 $string = htmlspecialchars ( $string );
 917         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 918                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 919         }
 920
 921         if( in_array( 'replaceafter', $options, true ) ) {
 922                 $string = wfMsgReplaceArgs( $string, $args );
 923         }
 924
 925         return $string;
 926 }
 927
 928
 929 /**
 930  * Just like exit() but makes a note of it.
 931  * Commits open transactions except if the error parameter is set
 932  *
 933  * @deprecated Please return control to the caller or throw an exception. Will
 934  *             be removed in 1.19.
 935  */
 936 function wfAbruptExit( $error = false ) {
 937         static $called = false;
 938         if ( $called ) {
 939                 exit( -1 );
 940         }
 941         $called = true;
 942
 943         wfDeprecated( __FUNCTION__ );
 944         $bt = wfDebugBacktrace();
 945         if( $bt ) {
 946                 for( $i = 0; $i < count( $bt ); $i++ ) {
 947                         $file = isset( $bt[$i]['file'] ) ? $bt[$i]['file'] : 'unknown';
 948                         $line = isset( $bt[$i]['line'] ) ? $bt[$i]['line'] : 'unknown';
 949                         wfDebug( "WARNING: Abrupt exit in $file at line $line\n");
 950                 }
 951         } else {
 952                 wfDebug( "WARNING: Abrupt exit\n" );
 953         }
 954
 955         wfLogProfilingData();
 956
 957         if ( !$error ) {
 958                 wfGetLB()->closeAll();
 959         }
 960         exit( -1 );
 961 }
 962
 963 /**
 964  * @deprecated Please return control the caller or throw an exception. Will
 965  *             be removed in 1.19.
 966  */
 967 function wfErrorExit() {
 968         wfDeprecated( __FUNCTION__ );
 969         wfAbruptExit( true );
 970 }
 971
 972 /**
 973  * Print a simple message and die, returning nonzero to the shell if any.
 974  * Plain die() fails to return nonzero to the shell if you pass a string.
 975  * @param $msg String
 976  */
 977 function wfDie( $msg = '' ) {
 978         echo $msg;
 979         die( 1 );
 980 }
 981
 982 /**
 983  * Throw a debugging exception. This function previously once exited the process,
 984  * but now throws an exception instead, with similar results.
 985  *
 986  * @param $msg String: message shown when dieing.
 987  */
 988 function wfDebugDieBacktrace( $msg = '' ) {
 989         throw new MWException( $msg );
 990 }
 991
 992 /**
 993  * Fetch server name for use in error reporting etc.
 994  * Use real server name if available, so we know which machine
 995  * in a server farm generated the current page.
 996  * @return string
 997  */
 998 function wfHostname() {
 999         static $host;
1000         if ( is_null( $host ) ) {
1001                 if ( function_exists( 'posix_uname' ) ) {
1002                         // This function not present on Windows
1003                         $uname = @posix_uname();
1004                 } else {
1005                         $uname = false;
1006                 }
1007                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1008                         $host = $uname['nodename'];
1009                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1010                         # Windows computer name
1011                         $host = getenv( 'COMPUTERNAME' );
1012                 } else {
1013                         # This may be a virtual server.
1014                         $host = $_SERVER['SERVER_NAME'];
1015                 }
1016         }
1017         return $host;
1018 }
1019
1020 /**
1021  * Returns a HTML comment with the elapsed time since request.
1022  * This method has no side effects.
1023  * @return string
1024  */
1025 function wfReportTime() {
1026         global $wgRequestTime, $wgShowHostnames;
1027
1028         $now = wfTime();
1029         $elapsed = $now - $wgRequestTime;
1030
1031         return $wgShowHostnames
1032                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1033                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1034 }
1035
1036 /**
1037  * Safety wrapper for debug_backtrace().
1038  *
1039  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1040  * murky circumstances, which may be triggered in part by stub objects
1041  * or other fancy talkin'.
1042  *
1043  * Will return an empty array if Zend Optimizer is detected or if
1044  * debug_backtrace is disabled, otherwise the output from
1045  * debug_backtrace() (trimmed).
1046  *
1047  * @return array of backtrace information
1048  */
1049 function wfDebugBacktrace() {
1050         static $disabled = null;
1051
1052         if( extension_loaded( 'Zend Optimizer' ) ) {
1053                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1054                 return array();
1055         }
1056
1057         if ( is_null( $disabled ) ) {
1058                 $disabled = false;
1059                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1060                 $functions = array_map( 'trim', $functions );
1061                 $functions = array_map( 'strtolower', $functions );
1062                 if ( in_array( 'debug_backtrace', $functions ) ) {
1063                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1064                         $disabled = true;
1065                 }
1066         }
1067         if ( $disabled ) {
1068                 return array();
1069         }
1070
1071         return array_slice( debug_backtrace(), 1 );
1072 }
1073
1074 function wfBacktrace() {
1075         global $wgCommandLineMode;
1076
1077         if ( $wgCommandLineMode ) {
1078                 $msg = '';
1079         } else {
1080                 $msg = "<ul>\n";
1081         }
1082         $backtrace = wfDebugBacktrace();
1083         foreach( $backtrace as $call ) {
1084                 if( isset( $call['file'] ) ) {
1085                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1086                         $file = $f[count( $f ) - 1];
1087                 } else {
1088                         $file = '-';
1089                 }
1090                 if( isset( $call['line'] ) ) {
1091                         $line = $call['line'];
1092                 } else {
1093                         $line = '-';
1094                 }
1095                 if ( $wgCommandLineMode ) {
1096                         $msg .= "$file line $line calls ";
1097                 } else {
1098                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1099                 }
1100                 if( !empty( $call['class'] ) ) {
1101                         $msg .= $call['class'] . '::';
1102                 }
1103                 $msg .= $call['function'] . '()';
1104
1105                 if ( $wgCommandLineMode ) {
1106                         $msg .= "\n";
1107                 } else {
1108                         $msg .= "</li>\n";
1109                 }
1110         }
1111         if ( $wgCommandLineMode ) {
1112                 $msg .= "\n";
1113         } else {
1114                 $msg .= "</ul>\n";
1115         }
1116
1117         return $msg;
1118 }
1119
1120
1121 /* Some generic result counters, pulled out of SearchEngine */
1122
1123
1124 /**
1125  * @todo document
1126  */
1127 function wfShowingResults( $offset, $limit ) {
1128         global $wgLang;
1129         return wfMsgExt(
1130                 'showingresults',
1131                 array( 'parseinline' ),
1132                 $wgLang->formatNum( $limit ),
1133                 $wgLang->formatNum( $offset + 1 )
1134         );
1135 }
1136
1137 /**
1138  * @todo document
1139  */
1140 function wfShowingResultsNum( $offset, $limit, $num ) {
1141         global $wgLang;
1142         return wfMsgExt(
1143                 'showingresultsnum',
1144                 array( 'parseinline' ),
1145                 $wgLang->formatNum( $limit ),
1146                 $wgLang->formatNum( $offset + 1 ),
1147                 $wgLang->formatNum( $num )
1148         );
1149 }
1150
1151 /**
1152  * Generate (prev x| next x) (20|50|100...) type links for paging
1153  * @param $offset String
1154  * @param $limit Integer
1155  * @param $link String
1156  * @param $query String: optional URL query parameter string
1157  * @param $atend Bool: optional param for specified if this is the last page
1158  */
1159 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1160         global $wgLang;
1161         $fmtLimit = $wgLang->formatNum( $limit );
1162         // FIXME: Why on earth this needs one message for the text and another one for tooltip??
1163         # Get prev/next link display text
1164         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1165         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1166         # Get prev/next link title text
1167         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1168         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1169         # Fetch the title object
1170         if( is_object( $link ) ) {
1171                 $title =& $link;
1172         } else {
1173                 $title = Title::newFromText( $link );
1174                 if( is_null( $title ) ) {
1175                         return false;
1176                 }
1177         }
1178         # Make 'previous' link
1179         if( 0 != $offset ) {
1180                 $po = $offset - $limit;
1181                 $po = max( $po, 0 );
1182                 $q = "limit={$limit}&offset={$po}";
1183                 if( $query != '' ) {
1184                         $q .= '&' . $query;
1185                 }
1186                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1187         } else {
1188                 $plink = $prev;
1189         }
1190         # Make 'next' link
1191         $no = $offset + $limit;
1192         $q = "limit={$limit}&offset={$no}";
1193         if( $query != '' ) {
1194                 $q .= '&' . $query;
1195         }
1196         if( $atend ) {
1197                 $nlink = $next;
1198         } else {
1199                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1200         }
1201         # Make links to set number of items per page
1202         $nums = $wgLang->pipeList( array(
1203                 wfNumLink( $offset, 20, $title, $query ),
1204                 wfNumLink( $offset, 50, $title, $query ),
1205                 wfNumLink( $offset, 100, $title, $query ),
1206                 wfNumLink( $offset, 250, $title, $query ),
1207                 wfNumLink( $offset, 500, $title, $query )
1208         ) );
1209         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1210 }
1211
1212 /**
1213  * Generate links for (20|50|100...) items-per-page links
1214  * @param $offset String
1215  * @param $limit Integer
1216  * @param $title Title
1217  * @param $query String: optional URL query parameter string
1218  */
1219 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1220         global $wgLang;
1221         if( $query == '' ) {
1222                 $q = '';
1223         } else {
1224                 $q = $query.'&';
1225         }
1226         $q .= "limit={$limit}&offset={$offset}";
1227         $fmtLimit = $wgLang->formatNum( $limit );
1228         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1229         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1230         return $s;
1231 }
1232
1233 /**
1234  * @todo document
1235  * @todo FIXME: we may want to blacklist some broken browsers
1236  *
1237  * @return bool Whereas client accept gzip compression
1238  */
1239 function wfClientAcceptsGzip() {
1240         static $result = null;
1241         if ( $result === null ) {
1242                 $result = false;
1243                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1244                         # FIXME: we may want to blacklist some broken browsers
1245                         $m = array();
1246                         if( preg_match(
1247                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1248                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1249                                 $m )
1250                         )
1251                         {
1252                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1253                                         $result = false;
1254                                         return $result;
1255                                 }
1256                                 wfDebug( " accepts gzip\n" );
1257                                 $result = true;
1258                         }
1259                 }
1260         }
1261         return $result;
1262 }
1263
1264 /**
1265  * Obtain the offset and limit values from the request string;
1266  * used in special pages
1267  *
1268  * @param $deflimit Default limit if none supplied
1269  * @param $optionname Name of a user preference to check against
1270  * @return array
1271  *
1272  */
1273 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1274         global $wgRequest;
1275         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1276 }
1277
1278 /**
1279  * Escapes the given text so that it may be output using addWikiText()
1280  * without any linking, formatting, etc. making its way through. This
1281  * is achieved by substituting certain characters with HTML entities.
1282  * As required by the callers, <nowiki> is not used. It currently does
1283  * not filter out characters which have special meaning only at the
1284  * start of a line, such as "*".
1285  *
1286  * @param $text String: text to be escaped
1287  */
1288 function wfEscapeWikiText( $text ) {
1289         $text = str_replace(
1290                 array( '[',     '|',      ']',     '\'',    'ISBN ',
1291                         'RFC ',     '://',     "\n=",     '{{',           '}}' ),
1292                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;',
1293                         'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;', '&#125;&#125;' ),
1294                 htmlspecialchars( $text )
1295         );
1296         return $text;
1297 }
1298
1299 /**
1300  * @todo document
1301  */
1302 function wfQuotedPrintable( $string, $charset = '' ) {
1303         # Probably incomplete; see RFC 2045
1304         if( empty( $charset ) ) {
1305                 global $wgInputEncoding;
1306                 $charset = $wgInputEncoding;
1307         }
1308         $charset = strtoupper( $charset );
1309         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
1310
1311         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
1312         $replace = $illegal . '\t ?_';
1313         if( !preg_match( "/[$illegal]/", $string ) ) {
1314                 return $string;
1315         }
1316         $out = "=?$charset?Q?";
1317         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
1318         $out .= '?=';
1319         return $out;
1320 }
1321
1322
1323 /**
1324  * @todo document
1325  * @return float
1326  */
1327 function wfTime() {
1328         return microtime( true );
1329 }
1330
1331 /**
1332  * Sets dest to source and returns the original value of dest
1333  * If source is NULL, it just returns the value, it doesn't set the variable
1334  */
1335 function wfSetVar( &$dest, $source ) {
1336         $temp = $dest;
1337         if ( !is_null( $source ) ) {
1338                 $dest = $source;
1339         }
1340         return $temp;
1341 }
1342
1343 /**
1344  * As for wfSetVar except setting a bit
1345  */
1346 function wfSetBit( &$dest, $bit, $state = true ) {
1347         $temp = (bool)( $dest & $bit );
1348         if ( !is_null( $state ) ) {
1349                 if ( $state ) {
1350                         $dest |= $bit;
1351                 } else {
1352                         $dest &= ~$bit;
1353                 }
1354         }
1355         return $temp;
1356 }
1357
1358 /**
1359  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1360  * "days=7&limit=100". Options in the first array override options in the second.
1361  * Options set to "" will not be output.
1362  */
1363 function wfArrayToCGI( $array1, $array2 = null ) {
1364         if ( !is_null( $array2 ) ) {
1365                 $array1 = $array1 + $array2;
1366         }
1367
1368         $cgi = '';
1369         foreach ( $array1 as $key => $value ) {
1370                 if ( $value !== '' ) {
1371                         if ( $cgi != '' ) {
1372                                 $cgi .= '&';
1373                         }
1374                         if ( is_array( $value ) ) {
1375                                 $firstTime = true;
1376                                 foreach ( $value as $v ) {
1377                                         $cgi .= ( $firstTime ? '' : '&') .
1378                                                 urlencode( $key . '[]' ) . '=' .
1379                                                 urlencode( $v );
1380                                         $firstTime = false;
1381                                 }
1382                         } else {
1383                                 if ( is_object( $value ) ) {
1384                                         $value = $value->__toString();
1385                                 }
1386                                 $cgi .= urlencode( $key ) . '=' .
1387                                         urlencode( $value );
1388                         }
1389                 }
1390         }
1391         return $cgi;
1392 }
1393
1394 /**
1395  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1396  * its argument and returns the same string in array form.  This allows compa-
1397  * tibility with legacy functions that accept raw query strings instead of nice
1398  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1399  * valid query strings, or it will explode.
1400  *
1401  * @param $query String: query string
1402  * @return array Array version of input
1403  */
1404 function wfCgiToArray( $query ) {
1405         if( isset( $query[0] ) && $query[0] == '?' ) {
1406                 $query = substr( $query, 1 );
1407         }
1408         $bits = explode( '&', $query );
1409         $ret = array();
1410         foreach( $bits as $bit ) {
1411                 if( $bit === '' ) {
1412                         continue;
1413                 }
1414                 list( $key, $value ) = explode( '=', $bit );
1415                 $key = urldecode( $key );
1416                 $value = urldecode( $value );
1417                 $ret[$key] = $value;
1418         }
1419         return $ret;
1420 }
1421
1422 /**
1423  * Append a query string to an existing URL, which may or may not already
1424  * have query string parameters already. If so, they will be combined.
1425  *
1426  * @param $url String
1427  * @param $query Mixed: string or associative array
1428  * @return string
1429  */
1430 function wfAppendQuery( $url, $query ) {
1431         if ( is_array( $query ) ) {
1432                 $query = wfArrayToCGI( $query );
1433         }
1434         if( $query != '' ) {
1435                 if( false === strpos( $url, '?' ) ) {
1436                         $url .= '?';
1437                 } else {
1438                         $url .= '&';
1439                 }
1440                 $url .= $query;
1441         }
1442         return $url;
1443 }
1444
1445 /**
1446  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1447  * and $wgProto are correct.
1448  *
1449  * @todo this won't work with current-path-relative URLs
1450  * like "subdir/foo.html", etc.
1451  *
1452  * @param $url String: either fully-qualified or a local path + query
1453  * @return string Fully-qualified URL
1454  */
1455 function wfExpandUrl( $url ) {
1456         if( substr( $url, 0, 2 ) == '//' ) {
1457                 global $wgProto;
1458                 return $wgProto . ':' . $url;
1459         } elseif( substr( $url, 0, 1 ) == '/' ) {
1460                 global $wgServer;
1461                 return $wgServer . $url;
1462         } else {
1463                 return $url;
1464         }
1465 }
1466
1467 /**
1468  * Windows-compatible version of escapeshellarg()
1469  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1470  * function puts single quotes in regardless of OS.
1471  *
1472  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1473  * earlier distro releases of PHP)
1474  */
1475 function wfEscapeShellArg( ) {
1476         wfInitShellLocale();
1477
1478         $args = func_get_args();
1479         $first = true;
1480         $retVal = '';
1481         foreach ( $args as $arg ) {
1482                 if ( !$first ) {
1483                         $retVal .= ' ';
1484                 } else {
1485                         $first = false;
1486                 }
1487
1488                 if ( wfIsWindows() ) {
1489                         // Escaping for an MSVC-style command line parser
1490                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1491                         // Double the backslashes before any double quotes. Escape the double quotes.
1492                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1493                         $arg = '';
1494                         $iteration = 0;
1495                         foreach ( $tokens as $token ) {
1496                                 if ( $iteration % 2 == 1 ) {
1497                                         // Delimiter, a double quote preceded by zero or more slashes
1498                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1499                                 } elseif ( $iteration % 4 == 2 ) {
1500                                         // ^ in $token will be outside quotes, need to be escaped
1501                                         $arg .= str_replace( '^', '^^', $token );
1502                                 } else { // $iteration % 4 == 0
1503                                         // ^ in $token will appear inside double quotes, so leave as is
1504                                         $arg .= $token;
1505                                 }
1506                                 $iteration++;
1507                         }
1508                         // Double the backslashes before the end of the string, because
1509                         // we will soon add a quote
1510                         $m = array();
1511                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1512                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1513                         }
1514
1515                         // Add surrounding quotes
1516                         $retVal .= '"' . $arg . '"';
1517                 } else {
1518                         $retVal .= escapeshellarg( $arg );
1519                 }
1520         }
1521         return $retVal;
1522 }
1523
1524 /**
1525  * wfMerge attempts to merge differences between three texts.
1526  * Returns true for a clean merge and false for failure or a conflict.
1527  */
1528 function wfMerge( $old, $mine, $yours, &$result ) {
1529         global $wgDiff3;
1530
1531         # This check may also protect against code injection in
1532         # case of broken installations.
1533         wfSuppressWarnings();
1534         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1535         wfRestoreWarnings();
1536
1537         if( !$haveDiff3 ) {
1538                 wfDebug( "diff3 not found\n" );
1539                 return false;
1540         }
1541
1542         # Make temporary files
1543         $td = wfTempDir();
1544         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1545         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1546         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1547
1548         fwrite( $oldtextFile, $old );
1549         fclose( $oldtextFile );
1550         fwrite( $mytextFile, $mine );
1551         fclose( $mytextFile );
1552         fwrite( $yourtextFile, $yours );
1553         fclose( $yourtextFile );
1554
1555         # Check for a conflict
1556         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1557                 wfEscapeShellArg( $mytextName ) . ' ' .
1558                 wfEscapeShellArg( $oldtextName ) . ' ' .
1559                 wfEscapeShellArg( $yourtextName );
1560         $handle = popen( $cmd, 'r' );
1561
1562         if( fgets( $handle, 1024 ) ) {
1563                 $conflict = true;
1564         } else {
1565                 $conflict = false;
1566         }
1567         pclose( $handle );
1568
1569         # Merge differences
1570         $cmd = $wgDiff3 . ' -a -e --merge ' .
1571                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1572         $handle = popen( $cmd, 'r' );
1573         $result = '';
1574         do {
1575                 $data = fread( $handle, 8192 );
1576                 if ( strlen( $data ) == 0 ) {
1577                         break;
1578                 }
1579                 $result .= $data;
1580         } while ( true );
1581         pclose( $handle );
1582         unlink( $mytextName );
1583         unlink( $oldtextName );
1584         unlink( $yourtextName );
1585
1586         if ( $result === '' && $old !== '' && !$conflict ) {
1587                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1588                 $conflict = true;
1589         }
1590         return !$conflict;
1591 }
1592
1593 /**
1594  * Returns unified plain-text diff of two texts.
1595  * Useful for machine processing of diffs.
1596  * @param $before String: the text before the changes.
1597  * @param $after String: the text after the changes.
1598  * @param $params String: command-line options for the diff command.
1599  * @return String: unified diff of $before and $after
1600  */
1601 function wfDiff( $before, $after, $params = '-u' ) {
1602         if ( $before == $after ) {
1603                 return '';
1604         }
1605
1606         global $wgDiff;
1607         wfSuppressWarnings();
1608         $haveDiff = $wgDiff && file_exists( $wgDiff );
1609         wfRestoreWarnings();
1610
1611         # This check may also protect against code injection in
1612         # case of broken installations.
1613         if( !$haveDiff ) {
1614                 wfDebug( "diff executable not found\n" );
1615                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1616                 $format = new UnifiedDiffFormatter();
1617                 return $format->format( $diffs );
1618         }
1619
1620         # Make temporary files
1621         $td = wfTempDir();
1622         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1623         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1624
1625         fwrite( $oldtextFile, $before );
1626         fclose( $oldtextFile );
1627         fwrite( $newtextFile, $after );
1628         fclose( $newtextFile );
1629
1630         // Get the diff of the two files
1631         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1632
1633         $h = popen( $cmd, 'r' );
1634
1635         $diff = '';
1636
1637         do {
1638                 $data = fread( $h, 8192 );
1639                 if ( strlen( $data ) == 0 ) {
1640                         break;
1641                 }
1642                 $diff .= $data;
1643         } while ( true );
1644
1645         // Clean up
1646         pclose( $h );
1647         unlink( $oldtextName );
1648         unlink( $newtextName );
1649
1650         // Kill the --- and +++ lines. They're not useful.
1651         $diff_lines = explode( "\n", $diff );
1652         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1653                 unset( $diff_lines[0] );
1654         }
1655         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1656                 unset( $diff_lines[1] );
1657         }
1658
1659         $diff = implode( "\n", $diff_lines );
1660
1661         return $diff;
1662 }
1663
1664 /**
1665  * A wrapper around the PHP function var_export().
1666  * Either print it or add it to the regular output ($wgOut).
1667  *
1668  * @param $var A PHP variable to dump.
1669  */
1670 function wfVarDump( $var ) {
1671         global $wgOut;
1672         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1673         if ( headers_sent() || !@is_object( $wgOut ) ) {
1674                 print $s;
1675         } else {
1676                 $wgOut->addHTML( $s );
1677         }
1678 }
1679
1680 /**
1681  * Provide a simple HTTP error.
1682  */
1683 function wfHttpError( $code, $label, $desc ) {
1684         global $wgOut;
1685         $wgOut->disable();
1686         header( "HTTP/1.0 $code $label" );
1687         header( "Status: $code $label" );
1688         $wgOut->sendCacheControl();
1689
1690         header( 'Content-type: text/html; charset=utf-8' );
1691         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1692                 '<html><head><title>' .
1693                 htmlspecialchars( $label ) .
1694                 '</title></head><body><h1>' .
1695                 htmlspecialchars( $label ) .
1696                 '</h1><p>' .
1697                 nl2br( htmlspecialchars( $desc ) ) .
1698                 "</p></body></html>\n";
1699 }
1700
1701 /**
1702  * Clear away any user-level output buffers, discarding contents.
1703  *
1704  * Suitable for 'starting afresh', for instance when streaming
1705  * relatively large amounts of data without buffering, or wanting to
1706  * output image files without ob_gzhandler's compression.
1707  *
1708  * The optional $resetGzipEncoding parameter controls suppression of
1709  * the Content-Encoding header sent by ob_gzhandler; by default it
1710  * is left. See comments for wfClearOutputBuffers() for why it would
1711  * be used.
1712  *
1713  * Note that some PHP configuration options may add output buffer
1714  * layers which cannot be removed; these are left in place.
1715  *
1716  * @param $resetGzipEncoding Bool
1717  */
1718 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1719         if( $resetGzipEncoding ) {
1720                 // Suppress Content-Encoding and Content-Length
1721                 // headers from 1.10+s wfOutputHandler
1722                 global $wgDisableOutputCompression;
1723                 $wgDisableOutputCompression = true;
1724         }
1725         while( $status = ob_get_status() ) {
1726                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1727                         // Probably from zlib.output_compression or other
1728                         // PHP-internal setting which can't be removed.
1729                         //
1730                         // Give up, and hope the result doesn't break
1731                         // output behavior.
1732                         break;
1733                 }
1734                 if( !ob_end_clean() ) {
1735                         // Could not remove output buffer handler; abort now
1736                         // to avoid getting in some kind of infinite loop.
1737                         break;
1738                 }
1739                 if( $resetGzipEncoding ) {
1740                         if( $status['name'] == 'ob_gzhandler' ) {
1741                                 // Reset the 'Content-Encoding' field set by this handler
1742                                 // so we can start fresh.
1743                                 header( 'Content-Encoding:' );
1744                                 break;
1745                         }
1746                 }
1747         }
1748 }
1749
1750 /**
1751  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1752  *
1753  * Clear away output buffers, but keep the Content-Encoding header
1754  * produced by ob_gzhandler, if any.
1755  *
1756  * This should be used for HTTP 304 responses, where you need to
1757  * preserve the Content-Encoding header of the real result, but
1758  * also need to suppress the output of ob_gzhandler to keep to spec
1759  * and avoid breaking Firefox in rare cases where the headers and
1760  * body are broken over two packets.
1761  */
1762 function wfClearOutputBuffers() {
1763         wfResetOutputBuffers( false );
1764 }
1765
1766 /**
1767  * Converts an Accept-* header into an array mapping string values to quality
1768  * factors
1769  */
1770 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1771         # No arg means accept anything (per HTTP spec)
1772         if( !$accept ) {
1773                 return array( $def => 1.0 );
1774         }
1775
1776         $prefs = array();
1777
1778         $parts = explode( ',', $accept );
1779
1780         foreach( $parts as $part ) {
1781                 # FIXME: doesn't deal with params like 'text/html; level=1'
1782                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1783                 $match = array();
1784                 if( !isset( $qpart ) ) {
1785                         $prefs[$value] = 1.0;
1786                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1787                         $prefs[$value] = floatval( $match[1] );
1788                 }
1789         }
1790
1791         return $prefs;
1792 }
1793
1794 /**
1795  * Checks if a given MIME type matches any of the keys in the given
1796  * array. Basic wildcards are accepted in the array keys.
1797  *
1798  * Returns the matching MIME type (or wildcard) if a match, otherwise
1799  * NULL if no match.
1800  *
1801  * @param $type String
1802  * @param $avail Array
1803  * @return string
1804  * @private
1805  */
1806 function mimeTypeMatch( $type, $avail ) {
1807         if( array_key_exists( $type, $avail ) ) {
1808                 return $type;
1809         } else {
1810                 $parts = explode( '/', $type );
1811                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1812                         return $parts[0] . '/*';
1813                 } elseif( array_key_exists( '*/*', $avail ) ) {
1814                         return '*/*';
1815                 } else {
1816                         return null;
1817                 }
1818         }
1819 }
1820
1821 /**
1822  * Returns the 'best' match between a client's requested internet media types
1823  * and the server's list of available types. Each list should be an associative
1824  * array of type to preference (preference is a float between 0.0 and 1.0).
1825  * Wildcards in the types are acceptable.
1826  *
1827  * @param $cprefs Array: client's acceptable type list
1828  * @param $sprefs Array: server's offered types
1829  * @return string
1830  *
1831  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1832  * XXX: generalize to negotiate other stuff
1833  */
1834 function wfNegotiateType( $cprefs, $sprefs ) {
1835         $combine = array();
1836
1837         foreach( array_keys($sprefs) as $type ) {
1838                 $parts = explode( '/', $type );
1839                 if( $parts[1] != '*' ) {
1840                         $ckey = mimeTypeMatch( $type, $cprefs );
1841                         if( $ckey ) {
1842                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1843                         }
1844                 }
1845         }
1846
1847         foreach( array_keys( $cprefs ) as $type ) {
1848                 $parts = explode( '/', $type );
1849                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1850                         $skey = mimeTypeMatch( $type, $sprefs );
1851                         if( $skey ) {
1852                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1853                         }
1854                 }
1855         }
1856
1857         $bestq = 0;
1858         $besttype = null;
1859
1860         foreach( array_keys( $combine ) as $type ) {
1861                 if( $combine[$type] > $bestq ) {
1862                         $besttype = $type;
1863                         $bestq = $combine[$type];
1864                 }
1865         }
1866
1867         return $besttype;
1868 }
1869
1870 /**
1871  * Array lookup
1872  * Returns an array where the values in the first array are replaced by the
1873  * values in the second array with the corresponding keys
1874  *
1875  * @return array
1876  */
1877 function wfArrayLookup( $a, $b ) {
1878         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1879 }
1880
1881 /**
1882  * Convenience function; returns MediaWiki timestamp for the present time.
1883  * @return string
1884  */
1885 function wfTimestampNow() {
1886         # return NOW
1887         return wfTimestamp( TS_MW, time() );
1888 }
1889
1890 /**
1891  * Reference-counted warning suppression
1892  */
1893 function wfSuppressWarnings( $end = false ) {
1894         static $suppressCount = 0;
1895         static $originalLevel = false;
1896
1897         if ( $end ) {
1898                 if ( $suppressCount ) {
1899                         --$suppressCount;
1900                         if ( !$suppressCount ) {
1901                                 error_reporting( $originalLevel );
1902                         }
1903                 }
1904         } else {
1905                 if ( !$suppressCount ) {
1906                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE ) );
1907                 }
1908                 ++$suppressCount;
1909         }
1910 }
1911
1912 /**
1913  * Restore error level to previous value
1914  */
1915 function wfRestoreWarnings() {
1916         wfSuppressWarnings( true );
1917 }
1918
1919 # Autodetect, convert and provide timestamps of various types
1920
1921 /**
1922  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1923  */
1924 define( 'TS_UNIX', 0 );
1925
1926 /**
1927  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1928  */
1929 define( 'TS_MW', 1 );
1930
1931 /**
1932  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1933  */
1934 define( 'TS_DB', 2 );
1935
1936 /**
1937  * RFC 2822 format, for E-mail and HTTP headers
1938  */
1939 define( 'TS_RFC2822', 3 );
1940
1941 /**
1942  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1943  *
1944  * This is used by Special:Export
1945  */
1946 define( 'TS_ISO_8601', 4 );
1947
1948 /**
1949  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1950  *
1951  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1952  *       DateTime tag and page 36 for the DateTimeOriginal and
1953  *       DateTimeDigitized tags.
1954  */
1955 define( 'TS_EXIF', 5 );
1956
1957 /**
1958  * Oracle format time.
1959  */
1960 define( 'TS_ORACLE', 6 );
1961
1962 /**
1963  * Postgres format time.
1964  */
1965 define( 'TS_POSTGRES', 7 );
1966
1967 /**
1968  * DB2 format time
1969  */
1970 define( 'TS_DB2', 8 );
1971
1972 /**
1973  * ISO 8601 basic format with no timezone: 19860209T200000Z
1974  *
1975  * This is used by ResourceLoader
1976  */
1977 define( 'TS_ISO_8601_BASIC', 9 );
1978
1979 /**
1980  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
1981  *                    function will autodetect which format is supplied and act
1982  *                    accordingly.
1983  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
1984  * @return Mixed: String / false The same date in the format specified in $outputtype or false
1985  */
1986 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1987         $uts = 0;
1988         $da = array();
1989         $strtime = '';
1990
1991         if ( $ts === 0 ) {
1992                 $uts = time();
1993                 $strtime = "@$uts";
1994         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1995                 # TS_DB
1996         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1997                 # TS_EXIF
1998         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
1999                 # TS_MW
2000         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2001                 # TS_UNIX
2002                 $uts = $ts;
2003                 $strtime = "@$ts"; // Undocumented?
2004         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2005                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2006                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2007                                 str_replace( '+00:00', 'UTC', $ts ) );
2008         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2009                 # TS_ISO_8601
2010         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2011                 #TS_ISO_8601_BASIC
2012         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2013                 # TS_POSTGRES
2014         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2015                 # TS_POSTGRES
2016         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2017                 # TS_DB2
2018         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2019                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2020                                                         '[ \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
2021                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2022                 # The regex is a superset of rfc2822 for readability
2023                 $strtime = strtok( $ts, ';' );
2024         } 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 ) ) {
2025                 # TS_RFC850
2026                 $strtime = $ts;
2027         } 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 ) ) {
2028                 # asctime
2029                 $strtime = $ts;
2030         } else {
2031                 # Bogus value; fall back to the epoch...
2032                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2033
2034                 return false;
2035         }
2036
2037
2038
2039         static $formats = array(
2040                 TS_UNIX => 'U',
2041                 TS_MW => 'YmdHis',
2042                 TS_DB => 'Y-m-d H:i:s',
2043                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2044                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2045                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2046                 TS_RFC2822 => 'D, d M Y H:i:s',
2047                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2048                 TS_POSTGRES => 'Y-m-d H:i:s',
2049                 TS_DB2 => 'Y-m-d H:i:s',
2050         );
2051
2052         if ( !isset( $formats[$outputtype] ) ) {
2053                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2054         }
2055
2056         if ( function_exists( "date_create" ) ) {
2057                 if ( count( $da ) ) {
2058                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2059                                 (int)$da[1], (int)$da[2], (int)$da[3],
2060                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2061
2062                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2063                 } elseif ( $strtime ) {
2064                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2065                 } else {
2066                         return false;
2067                 }
2068
2069                 if ( !$d ) {
2070                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2071                         return false;
2072                 }
2073
2074                 $output = $d->format( $formats[$outputtype] );
2075         } else {
2076                 if ( count( $da ) ) {
2077                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2078                         // We may want to handle that explicitly at some point
2079                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2080                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2081                 } elseif ( $strtime ) {
2082                         $uts = strtotime( $strtime );
2083                 }
2084
2085                 if ( $uts === false ) {
2086                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2087                         return false;
2088                 }
2089
2090                 if ( TS_UNIX == $outputtype ) {
2091                         return $uts;
2092                 }
2093                 $output = gmdate( $formats[$outputtype], $uts );
2094         }
2095
2096         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2097                 $output .= ' GMT';
2098         }
2099
2100         return $output;
2101 }
2102
2103 /**
2104  * Return a formatted timestamp, or null if input is null.
2105  * For dealing with nullable timestamp columns in the database.
2106  * @param $outputtype Integer
2107  * @param $ts String
2108  * @return String
2109  */
2110 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2111         if( is_null( $ts ) ) {
2112                 return null;
2113         } else {
2114                 return wfTimestamp( $outputtype, $ts );
2115         }
2116 }
2117
2118 /**
2119  * Check if the operating system is Windows
2120  *
2121  * @return Bool: true if it's Windows, False otherwise.
2122  */
2123 function wfIsWindows() {
2124         static $isWindows = null;
2125         if ( $isWindows === null ) {
2126                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2127         }
2128         return $isWindows;
2129 }
2130
2131 /**
2132  * Swap two variables
2133  */
2134 function swap( &$x, &$y ) {
2135         $z = $x;
2136         $x = $y;
2137         $y = $z;
2138 }
2139
2140 function wfGetCachedNotice( $name ) {
2141         global $wgOut, $wgRenderHashAppend, $parserMemc;
2142         $fname = 'wfGetCachedNotice';
2143         wfProfileIn( $fname );
2144
2145         $needParse = false;
2146
2147         if( $name === 'default' ) {
2148                 // special case
2149                 global $wgSiteNotice;
2150                 $notice = $wgSiteNotice;
2151                 if( empty( $notice ) ) {
2152                         wfProfileOut( $fname );
2153                         return false;
2154                 }
2155         } else {
2156                 $notice = wfMsgForContentNoTrans( $name );
2157                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
2158                         wfProfileOut( $fname );
2159                         return( false );
2160                 }
2161         }
2162
2163         // Use the extra hash appender to let eg SSL variants separately cache.
2164         $key = wfMemcKey( $name . $wgRenderHashAppend );
2165         $cachedNotice = $parserMemc->get( $key );
2166         if( is_array( $cachedNotice ) ) {
2167                 if( md5( $notice ) == $cachedNotice['hash'] ) {
2168                         $notice = $cachedNotice['html'];
2169                 } else {
2170                         $needParse = true;
2171                 }
2172         } else {
2173                 $needParse = true;
2174         }
2175
2176         if( $needParse ) {
2177                 if( is_object( $wgOut ) ) {
2178                         $parsed = $wgOut->parse( $notice );
2179                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
2180                         $notice = $parsed;
2181                 } else {
2182                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' . "\n" );
2183                         $notice = '';
2184                 }
2185         }
2186         $notice = '<div id="localNotice">' .$notice . '</div>';
2187         wfProfileOut( $fname );
2188         return $notice;
2189 }
2190
2191 function wfGetNamespaceNotice() {
2192         global $wgTitle;
2193
2194         # Paranoia
2195         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) ) {
2196                 return '';
2197         }
2198
2199         $fname = 'wfGetNamespaceNotice';
2200         wfProfileIn( $fname );
2201
2202         $key = 'namespacenotice-' . $wgTitle->getNsText();
2203         $namespaceNotice = wfGetCachedNotice( $key );
2204         if ( $namespaceNotice && substr( $namespaceNotice, 0, 7 ) != '<p>&lt;' ) {
2205                 $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . '</div>';
2206         } else {
2207                 $namespaceNotice = '';
2208         }
2209
2210         wfProfileOut( $fname );
2211         return $namespaceNotice;
2212 }
2213
2214 function wfGetSiteNotice() {
2215         global $wgUser;
2216         $fname = 'wfGetSiteNotice';
2217         wfProfileIn( $fname );
2218         $siteNotice = '';
2219
2220         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
2221                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
2222                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
2223                 } else {
2224                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
2225                         if( !$anonNotice ) {
2226                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
2227                         } else {
2228                                 $siteNotice = $anonNotice;
2229                         }
2230                 }
2231                 if( !$siteNotice ) {
2232                         $siteNotice = wfGetCachedNotice( 'default' );
2233                 }
2234         }
2235
2236         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
2237         wfProfileOut( $fname );
2238         return $siteNotice;
2239 }
2240
2241 /**
2242  * BC wrapper for MimeMagic::singleton()
2243  * @deprecated No longer needed as of 1.17 (r68836).
2244  */
2245 function &wfGetMimeMagic() {
2246         wfDeprecated( __FUNCTION__ );
2247         return MimeMagic::singleton();
2248 }
2249
2250 /**
2251  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2252  * TEMP environment variables are then checked in sequence, and if none are set
2253  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2254  * or C:\Windows\Temp for Windows and hope for the best.
2255  * It is common to call it with tempnam().
2256  *
2257  * NOTE: When possible, use instead the tmpfile() function to create
2258  * temporary files to avoid race conditions on file creation, etc.
2259  *
2260  * @return String
2261  */
2262 function wfTempDir() {
2263         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2264                 $tmp = getenv( $var );
2265                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2266                         return $tmp;
2267                 }
2268         }
2269         if( function_exists( 'sys_get_temp_dir' ) ) {
2270                 return sys_get_temp_dir();
2271         }
2272         # Usual defaults
2273         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2274 }
2275
2276 /**
2277  * Make directory, and make all parent directories if they don't exist
2278  *
2279  * @param $dir String: full path to directory to create
2280  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2281  * @param $caller String: optional caller param for debugging.
2282  * @return bool
2283  */
2284 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2285         global $wgDirectoryMode;
2286
2287         if ( !is_null( $caller ) ) {
2288                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2289         }
2290
2291         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2292                 return true;
2293         }
2294
2295         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2296
2297         if ( is_null( $mode ) ) {
2298                 $mode = $wgDirectoryMode;
2299         }
2300
2301         // Turn off the normal warning, we're doing our own below
2302         wfSuppressWarnings();
2303         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2304         wfRestoreWarnings();
2305
2306         if( !$ok ) {
2307                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2308                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2309         }
2310         return $ok;
2311 }
2312
2313 /**
2314  * Increment a statistics counter
2315  */
2316 function wfIncrStats( $key ) {
2317         global $wgStatsMethod;
2318
2319         if( $wgStatsMethod == 'udp' ) {
2320                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
2321                 static $socket;
2322                 if ( !$socket ) {
2323                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2324                         $statline = "stats/{$wgDBname} - 1 1 1 1 1 -total\n";
2325                         socket_sendto(
2326                                 $socket,
2327                                 $statline,
2328                                 strlen( $statline ),
2329                                 0,
2330                                 $wgUDPProfilerHost,
2331                                 $wgUDPProfilerPort
2332                         );
2333                 }
2334                 $statline = "stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
2335                 wfSuppressWarnings();
2336                 socket_sendto(
2337                         $socket,
2338                         $statline,
2339                         strlen( $statline ),
2340                         0,
2341                         $wgUDPProfilerHost,
2342                         $wgUDPProfilerPort
2343                 );
2344                 wfRestoreWarnings();
2345         } elseif( $wgStatsMethod == 'cache' ) {
2346                 global $wgMemc;
2347                 $key = wfMemcKey( 'stats', $key );
2348                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2349                         $wgMemc->add( $key, 1 );
2350                 }
2351         } else {
2352                 // Disabled
2353         }
2354 }
2355
2356 /**
2357  * @param $nr Mixed: the number to format
2358  * @param $acc Integer: the number of digits after the decimal point, default 2
2359  * @param $round Boolean: whether or not to round the value, default true
2360  * @return float
2361  */
2362 function wfPercent( $nr, $acc = 2, $round = true ) {
2363         $ret = sprintf( "%.${acc}f", $nr );
2364         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2365 }
2366
2367 /**
2368  * Encrypt a username/password.
2369  *
2370  * @param $userid Integer: ID of the user
2371  * @param $password String: password of the user
2372  * @return String: hashed password
2373  * @deprecated Use User::crypt() or User::oldCrypt() instead
2374  */
2375 function wfEncryptPassword( $userid, $password ) {
2376         wfDeprecated(__FUNCTION__);
2377         # Just wrap around User::oldCrypt()
2378         return User::oldCrypt( $password, $userid );
2379 }
2380
2381 /**
2382  * Appends to second array if $value differs from that in $default
2383  */
2384 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2385         if ( is_null( $changed ) ) {
2386                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
2387         }
2388         if ( $default[$key] !== $value ) {
2389                 $changed[$key] = $value;
2390         }
2391 }
2392
2393 /**
2394  * Since wfMsg() and co suck, they don't return false if the message key they
2395  * looked up didn't exist but a XHTML string, this function checks for the
2396  * nonexistance of messages by looking at wfMsg() output
2397  *
2398  * @param $key      String: the message key looked up
2399  * @return Boolean True if the message *doesn't* exist.
2400  */
2401 function wfEmptyMsg( $key ) {
2402         global $wgMessageCache;
2403         return $wgMessageCache->get( $key, /*useDB*/true, /*content*/false ) === false;
2404 }
2405
2406 /**
2407  * Find out whether or not a mixed variable exists in a string
2408  *
2409  * @param $needle String
2410  * @param $str String
2411  * @return Boolean
2412  */
2413 function in_string( $needle, $str ) {
2414         return strpos( $str, $needle ) !== false;
2415 }
2416
2417 function wfSpecialList( $page, $details ) {
2418         global $wgContLang;
2419         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2420         return $page . $details;
2421 }
2422
2423 /**
2424  * Returns a regular expression of url protocols
2425  *
2426  * @return String
2427  */
2428 function wfUrlProtocols() {
2429         global $wgUrlProtocols;
2430
2431         static $retval = null;
2432         if ( !is_null( $retval ) ) {
2433                 return $retval;
2434         }
2435
2436         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2437         // with LocalSettings files from 1.5
2438         if ( is_array( $wgUrlProtocols ) ) {
2439                 $protocols = array();
2440                 foreach ( $wgUrlProtocols as $protocol ) {
2441                         $protocols[] = preg_quote( $protocol, '/' );
2442                 }
2443
2444                 $retval = implode( '|', $protocols );
2445         } else {
2446                 $retval = $wgUrlProtocols;
2447         }
2448         return $retval;
2449 }
2450
2451 /**
2452  * Safety wrapper around ini_get() for boolean settings.
2453  * The values returned from ini_get() are pre-normalized for settings
2454  * set via php.ini or php_flag/php_admin_flag... but *not*
2455  * for those set via php_value/php_admin_value.
2456  *
2457  * It's fairly common for people to use php_value instead of php_flag,
2458  * which can leave you with an 'off' setting giving a false positive
2459  * for code that just takes the ini_get() return value as a boolean.
2460  *
2461  * To make things extra interesting, setting via php_value accepts
2462  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2463  * Unrecognized values go false... again opposite PHP's own coercion
2464  * from string to bool.
2465  *
2466  * Luckily, 'properly' set settings will always come back as '0' or '1',
2467  * so we only have to worry about them and the 'improper' settings.
2468  *
2469  * I frickin' hate PHP... :P
2470  *
2471  * @param $setting String
2472  * @return Bool
2473  */
2474 function wfIniGetBool( $setting ) {
2475         $val = ini_get( $setting );
2476         // 'on' and 'true' can't have whitespace around them, but '1' can.
2477         return strtolower( $val ) == 'on'
2478                 || strtolower( $val ) == 'true'
2479                 || strtolower( $val ) == 'yes'
2480                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2481 }
2482
2483 /**
2484  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2485  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2486  *
2487  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2488  *                          should be omitted
2489  * @return Bool - Whether or not the extension is loaded
2490  */
2491 function wfDl( $extension ) {
2492         if( extension_loaded( $extension ) ) {
2493                 return true;
2494         }
2495
2496         $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2497                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2498
2499         if( $canDl ) {
2500                 wfSuppressWarnings();
2501                 dl( $extension . '.' . PHP_SHLIB_SUFFIX );
2502                 wfRestoreWarnings();
2503         }
2504         return extension_loaded( $extension );
2505 }
2506
2507 /**
2508  * Execute a shell command, with time and memory limits mirrored from the PHP
2509  * configuration if supported.
2510  * @param $cmd String Command line, properly escaped for shell.
2511  * @param &$retval optional, will receive the program's exit code.
2512  *                 (non-zero is usually failure)
2513  * @param $environ Array optional environment variables which should be
2514  *                 added to the executed command environment.
2515  * @return collected stdout as a string (trailing newlines stripped)
2516  */
2517 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2518         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2519
2520         static $disabled;
2521         if ( is_null( $disabled ) ) {
2522                 $disabled = false;
2523                 if( wfIniGetBool( 'safe_mode' ) ) {
2524                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2525                         $disabled = 'safemode';
2526                 } else {
2527                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2528                         $functions = array_map( 'trim', $functions );
2529                         $functions = array_map( 'strtolower', $functions );
2530                         if ( in_array( 'passthru', $functions ) ) {
2531                                 wfDebug( "passthru is in disabled_functions\n" );
2532                                 $disabled = 'passthru';
2533                         }
2534                 }
2535         }
2536         if ( $disabled ) {
2537                 $retval = 1;
2538                 return $disabled == 'safemode' ?
2539                         'Unable to run external programs in safe mode.' :
2540                         'Unable to run external programs, passthru() is disabled.';
2541         }
2542
2543         wfInitShellLocale();
2544
2545         $envcmd = '';
2546         foreach( $environ as $k => $v ) {
2547                 if ( wfIsWindows() ) {
2548                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2549                          * appear in the environment variable, so we must use carat escaping as documented in
2550                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2551                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2552                          * are listed there but doesn't appear to need it.
2553                          */
2554                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . ' && ';
2555                 } else {
2556                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2557                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2558                          */
2559                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2560                 }
2561         }
2562         $cmd = $envcmd . $cmd;
2563
2564         if ( wfIsWindows() ) {
2565                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2566                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2567                 {
2568                         # Hack to work around PHP's flawed invocation of cmd.exe
2569                         # http://news.php.net/php.internals/21796
2570                         # Windows 9x doesn't accept any kind of quotes
2571                         $cmd = '"' . $cmd . '"';
2572                 }
2573         } elseif ( php_uname( 's' ) == 'Linux' ) {
2574                 $time = intval( $wgMaxShellTime );
2575                 $mem = intval( $wgMaxShellMemory );
2576                 $filesize = intval( $wgMaxShellFileSize );
2577
2578                 if ( $time > 0 && $mem > 0 ) {
2579                         $script = "$IP/bin/ulimit4.sh";
2580                         if ( is_executable( $script ) ) {
2581                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2582                         }
2583                 }
2584         }
2585         wfDebug( "wfShellExec: $cmd\n" );
2586
2587         $retval = 1; // error by default?
2588         ob_start();
2589         passthru( $cmd, $retval );
2590         $output = ob_get_contents();
2591         ob_end_clean();
2592
2593         if ( $retval == 127 ) {
2594                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2595         }
2596         return $output;
2597 }
2598
2599 /**
2600  * Workaround for http://bugs.php.net/bug.php?id=45132
2601  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2602  */
2603 function wfInitShellLocale() {
2604         static $done = false;
2605         if ( $done ) {
2606                 return;
2607         }
2608         $done = true;
2609         global $wgShellLocale;
2610         if ( !wfIniGetBool( 'safe_mode' ) ) {
2611                 putenv( "LC_CTYPE=$wgShellLocale" );
2612                 setlocale( LC_CTYPE, $wgShellLocale );
2613         }
2614 }
2615
2616 /**
2617  * This function works like "use VERSION" in Perl, the program will die with a
2618  * backtrace if the current version of PHP is less than the version provided
2619  *
2620  * This is useful for extensions which due to their nature are not kept in sync
2621  * with releases, and might depend on other versions of PHP than the main code
2622  *
2623  * Note: PHP might die due to parsing errors in some cases before it ever
2624  *       manages to call this function, such is life
2625  *
2626  * @see perldoc -f use
2627  *
2628  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2629  *                 a float
2630  */
2631 function wfUsePHP( $req_ver ) {
2632         $php_ver = PHP_VERSION;
2633
2634         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2635                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2636         }
2637 }
2638
2639 /**
2640  * This function works like "use VERSION" in Perl except it checks the version
2641  * of MediaWiki, the program will die with a backtrace if the current version
2642  * of MediaWiki is less than the version provided.
2643  *
2644  * This is useful for extensions which due to their nature are not kept in sync
2645  * with releases
2646  *
2647  * @see perldoc -f use
2648  *
2649  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2650  *                 a float
2651  */
2652 function wfUseMW( $req_ver ) {
2653         global $wgVersion;
2654
2655         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2656                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2657         }
2658 }
2659
2660 /**
2661  * Return the final portion of a pathname.
2662  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2663  * http://bugs.php.net/bug.php?id=33898
2664  *
2665  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2666  * We'll consider it so always, as we don't want \s in our Unix paths either.
2667  *
2668  * @param $path String
2669  * @param $suffix String: to remove if present
2670  * @return String
2671  */
2672 function wfBaseName( $path, $suffix = '' ) {
2673         $encSuffix = ( $suffix == '' )
2674                 ? ''
2675                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2676         $matches = array();
2677         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2678                 return $matches[1];
2679         } else {
2680                 return '';
2681         }
2682 }
2683
2684 /**
2685  * Generate a relative path name to the given file.
2686  * May explode on non-matching case-insensitive paths,
2687  * funky symlinks, etc.
2688  *
2689  * @param $path String: absolute destination path including target filename
2690  * @param $from String: Absolute source path, directory only
2691  * @return String
2692  */
2693 function wfRelativePath( $path, $from ) {
2694         // Normalize mixed input on Windows...
2695         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2696         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2697
2698         // Trim trailing slashes -- fix for drive root
2699         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2700         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2701
2702         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2703         $against = explode( DIRECTORY_SEPARATOR, $from );
2704
2705         if( $pieces[0] !== $against[0] ) {
2706                 // Non-matching Windows drive letters?
2707                 // Return a full path.
2708                 return $path;
2709         }
2710
2711         // Trim off common prefix
2712         while( count( $pieces ) && count( $against )
2713                 && $pieces[0] == $against[0] ) {
2714                 array_shift( $pieces );
2715                 array_shift( $against );
2716         }
2717
2718         // relative dots to bump us to the parent
2719         while( count( $against ) ) {
2720                 array_unshift( $pieces, '..' );
2721                 array_shift( $against );
2722         }
2723
2724         array_push( $pieces, wfBaseName( $path ) );
2725
2726         return implode( DIRECTORY_SEPARATOR, $pieces );
2727 }
2728
2729 /**
2730  * Backwards array plus for people who haven't bothered to read the PHP manual
2731  * XXX: will not darn your socks for you.
2732  *
2733  * @param $array1 Array
2734  * @param [$array2, [...]] Arrays
2735  * @return Array
2736  */
2737 function wfArrayMerge( $array1/* ... */ ) {
2738         $args = func_get_args();
2739         $args = array_reverse( $args, true );
2740         $out = array();
2741         foreach ( $args as $arg ) {
2742                 $out += $arg;
2743         }
2744         return $out;
2745 }
2746
2747 /**
2748  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
2749  * e.g.
2750  *      wfMergeErrorArrays(
2751  *              array( array( 'x' ) ),
2752  *              array( array( 'x', '2' ) ),
2753  *              array( array( 'x' ) ),
2754  *              array( array( 'y') )
2755  *      );
2756  * returns:
2757  *              array(
2758  *              array( 'x', '2' ),
2759  *              array( 'x' ),
2760  *              array( 'y' )
2761  *      )
2762  */
2763 function wfMergeErrorArrays( /*...*/ ) {
2764         $args = func_get_args();
2765         $out = array();
2766         foreach ( $args as $errors ) {
2767                 foreach ( $errors as $params ) {
2768                         # FIXME: sometimes get nested arrays for $params,
2769                         # which leads to E_NOTICEs
2770                         $spec = implode( "\t", $params );
2771                         $out[$spec] = $params;
2772                 }
2773         }
2774         return array_values( $out );
2775 }
2776
2777 /**
2778  * parse_url() work-alike, but non-broken.  Differences:
2779  *
2780  * 1) Does not raise warnings on bad URLs (just returns false)
2781  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2782  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2783  *
2784  * @param $url String: a URL to parse
2785  * @return Array: bits of the URL in an associative array, per PHP docs
2786  */
2787 function wfParseUrl( $url ) {
2788         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2789         wfSuppressWarnings();
2790         $bits = parse_url( $url );
2791         wfRestoreWarnings();
2792         if ( !$bits ) {
2793                 return false;
2794         }
2795
2796         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2797         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2798                 $bits['delimiter'] = '://';
2799         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2800                 $bits['delimiter'] = ':';
2801                 // parse_url detects for news: and mailto: the host part of an url as path
2802                 // We have to correct this wrong detection
2803                 if ( isset( $bits['path'] ) ) {
2804                         $bits['host'] = $bits['path'];
2805                         $bits['path'] = '';
2806                 }
2807         } else {
2808                 return false;
2809         }
2810
2811         return $bits;
2812 }
2813
2814 /**
2815  * Make a URL index, appropriate for the el_index field of externallinks.
2816  */
2817 function wfMakeUrlIndex( $url ) {
2818         $bits = wfParseUrl( $url );
2819
2820         // Reverse the labels in the hostname, convert to lower case
2821         // For emails reverse domainpart only
2822         if ( $bits['scheme'] == 'mailto' ) {
2823                 $mailparts = explode( '@', $bits['host'], 2 );
2824                 if ( count( $mailparts ) === 2 ) {
2825                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2826                 } else {
2827                         // No domain specified, don't mangle it
2828                         $domainpart = '';
2829                 }
2830                 $reversedHost = $domainpart . '@' . $mailparts[0];
2831         } else {
2832                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2833         }
2834         // Add an extra dot to the end
2835         // Why? Is it in wrong place in mailto links?
2836         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2837                 $reversedHost .= '.';
2838         }
2839         // Reconstruct the pseudo-URL
2840         $prot = $bits['scheme'];
2841         $index = $prot . $bits['delimiter'] . $reversedHost;
2842         // Leave out user and password. Add the port, path, query and fragment
2843         if ( isset( $bits['port'] ) ) {
2844                 $index .= ':' . $bits['port'];
2845         }
2846         if ( isset( $bits['path'] ) ) {
2847                 $index .= $bits['path'];
2848         } else {
2849                 $index .= '/';
2850         }
2851         if ( isset( $bits['query'] ) ) {
2852                 $index .= '?' . $bits['query'];
2853         }
2854         if ( isset( $bits['fragment'] ) ) {
2855                 $index .= '#' . $bits['fragment'];
2856         }
2857         return $index;
2858 }
2859
2860 /**
2861  * Do any deferred updates and clear the list
2862  * TODO: This could be in Wiki.php if that class made any sense at all
2863  */
2864 function wfDoUpdates() {
2865         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2866         foreach ( $wgDeferredUpdateList as $update ) {
2867                 $update->doUpdate();
2868         }
2869         foreach ( $wgPostCommitUpdateList as $update ) {
2870                 $update->doUpdate();
2871         }
2872         $wgDeferredUpdateList = array();
2873         $wgPostCommitUpdateList = array();
2874 }
2875
2876 /**
2877  * Convert an arbitrarily-long digit string from one numeric base
2878  * to another, optionally zero-padding to a minimum column width.
2879  *
2880  * Supports base 2 through 36; digit values 10-36 are represented
2881  * as lowercase letters a-z. Input is case-insensitive.
2882  *
2883  * @param $input String: of digits
2884  * @param $sourceBase Integer: 2-36
2885  * @param $destBase Integer: 2-36
2886  * @param $pad Integer: 1 or greater
2887  * @param $lowercase Boolean
2888  * @return String or false on invalid input
2889  */
2890 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2891         $input = strval( $input );
2892         if( $sourceBase < 2 ||
2893                 $sourceBase > 36 ||
2894                 $destBase < 2 ||
2895                 $destBase > 36 ||
2896                 $pad < 1 ||
2897                 $sourceBase != intval( $sourceBase ) ||
2898                 $destBase != intval( $destBase ) ||
2899                 $pad != intval( $pad ) ||
2900                 !is_string( $input ) ||
2901                 $input == '' ) {
2902                 return false;
2903         }
2904         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2905         $inDigits = array();
2906         $outChars = '';
2907
2908         // Decode and validate input string
2909         $input = strtolower( $input );
2910         for( $i = 0; $i < strlen( $input ); $i++ ) {
2911                 $n = strpos( $digitChars, $input{$i} );
2912                 if( $n === false || $n > $sourceBase ) {
2913                         return false;
2914                 }
2915                 $inDigits[] = $n;
2916         }
2917
2918         // Iterate over the input, modulo-ing out an output digit
2919         // at a time until input is gone.
2920         while( count( $inDigits ) ) {
2921                 $work = 0;
2922                 $workDigits = array();
2923
2924                 // Long division...
2925                 foreach( $inDigits as $digit ) {
2926                         $work *= $sourceBase;
2927                         $work += $digit;
2928
2929                         if( $work < $destBase ) {
2930                                 // Gonna need to pull another digit.
2931                                 if( count( $workDigits ) ) {
2932                                         // Avoid zero-padding; this lets us find
2933                                         // the end of the input very easily when
2934                                         // length drops to zero.
2935                                         $workDigits[] = 0;
2936                                 }
2937                         } else {
2938                                 // Finally! Actual division!
2939                                 $workDigits[] = intval( $work / $destBase );
2940
2941                                 // Isn't it annoying that most programming languages
2942                                 // don't have a single divide-and-remainder operator,
2943                                 // even though the CPU implements it that way?
2944                                 $work = $work % $destBase;
2945                         }
2946                 }
2947
2948                 // All that division leaves us with a remainder,
2949                 // which is conveniently our next output digit.
2950                 $outChars .= $digitChars[$work];
2951
2952                 // And we continue!
2953                 $inDigits = $workDigits;
2954         }
2955
2956         while( strlen( $outChars ) < $pad ) {
2957                 $outChars .= '0';
2958         }
2959
2960         return strrev( $outChars );
2961 }
2962
2963 /**
2964  * Create an object with a given name and an array of construct parameters
2965  * @param $name String
2966  * @param $p Array: parameters
2967  */
2968 function wfCreateObject( $name, $p ) {
2969         $p = array_values( $p );
2970         switch ( count( $p ) ) {
2971                 case 0:
2972                         return new $name;
2973                 case 1:
2974                         return new $name( $p[0] );
2975                 case 2:
2976                         return new $name( $p[0], $p[1] );
2977                 case 3:
2978                         return new $name( $p[0], $p[1], $p[2] );
2979                 case 4:
2980                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2981                 case 5:
2982                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2983                 case 6:
2984                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2985                 default:
2986                         throw new MWException( 'Too many arguments to construtor in wfCreateObject' );
2987         }
2988 }
2989
2990 function wfHttpOnlySafe() {
2991         global $wgHttpOnlyBlacklist;
2992         if( !version_compare( '5.2', PHP_VERSION, '<' ) ) {
2993                 return false;
2994         }
2995
2996         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2997                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2998                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2999                                 return false;
3000                         }
3001                 }
3002         }
3003
3004         return true;
3005 }
3006
3007 /**
3008  * Initialise php session
3009  */
3010 function wfSetupSession( $sessionId = false ) {
3011         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3012                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3013         if( $wgSessionsInMemcached ) {
3014                 require_once( 'MemcachedSessions.php' );
3015         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3016                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3017                 # hasn't already been set to the desired value (that causes errors)
3018                 ini_set( 'session.save_handler', $wgSessionHandler );
3019         }
3020         $httpOnlySafe = wfHttpOnlySafe();
3021         wfDebugLog( 'cookie',
3022                 'session_set_cookie_params: "' . implode( '", "',
3023                         array(
3024                                 0,
3025                                 $wgCookiePath,
3026                                 $wgCookieDomain,
3027                                 $wgCookieSecure,
3028                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
3029         if( $httpOnlySafe && $wgCookieHttpOnly ) {
3030                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
3031         } else {
3032                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
3033                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
3034         }
3035         session_cache_limiter( 'private, must-revalidate' );
3036         if ( $sessionId ) {
3037                 session_id( $sessionId );
3038         }
3039         wfSuppressWarnings();
3040         session_start();
3041         wfRestoreWarnings();
3042 }
3043
3044 /**
3045  * Get an object from the precompiled serialized directory
3046  *
3047  * @return Mixed: the variable on success, false on failure
3048  */
3049 function wfGetPrecompiledData( $name ) {
3050         global $IP;
3051
3052         $file = "$IP/serialized/$name";
3053         if ( file_exists( $file ) ) {
3054                 $blob = file_get_contents( $file );
3055                 if ( $blob ) {
3056                         return unserialize( $blob );
3057                 }
3058         }
3059         return false;
3060 }
3061
3062 function wfGetCaller( $level = 2 ) {
3063         $backtrace = wfDebugBacktrace();
3064         if ( isset( $backtrace[$level] ) ) {
3065                 return wfFormatStackFrame( $backtrace[$level] );
3066         } else {
3067                 $caller = 'unknown';
3068         }
3069         return $caller;
3070 }
3071
3072 /**
3073  * Return a string consisting of callers in the stack. Useful sometimes
3074  * for profiling specific points.
3075  *
3076  * @param $limit The maximum depth of the stack frame to return, or false for
3077  *               the entire stack.
3078  */
3079 function wfGetAllCallers( $limit = 3 ) {
3080         $trace = array_reverse( wfDebugBacktrace() );
3081         if ( !$limit || $limit > count( $trace ) - 1 ) {
3082                 $limit = count( $trace ) - 1;
3083         }
3084         $trace = array_slice( $trace, -$limit - 1, $limit );
3085         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
3086 }
3087
3088 /**
3089  * Return a string representation of frame
3090  */
3091 function wfFormatStackFrame( $frame ) {
3092         return isset( $frame['class'] ) ?
3093                 $frame['class'] . '::' . $frame['function'] :
3094                 $frame['function'];
3095 }
3096
3097 /**
3098  * Get a cache key
3099  */
3100 function wfMemcKey( /*... */ ) {
3101         $args = func_get_args();
3102         $key = wfWikiID() . ':' . implode( ':', $args );
3103         $key = str_replace( ' ', '_', $key );
3104         return $key;
3105 }
3106
3107 /**
3108  * Get a cache key for a foreign DB
3109  */
3110 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3111         $args = array_slice( func_get_args(), 2 );
3112         if ( $prefix ) {
3113                 $key = "$db-$prefix:" . implode( ':', $args );
3114         } else {
3115                 $key = $db . ':' . implode( ':', $args );
3116         }
3117         return $key;
3118 }
3119
3120 /**
3121  * Get an ASCII string identifying this wiki
3122  * This is used as a prefix in memcached keys
3123  */
3124 function wfWikiID() {
3125         global $wgDBprefix, $wgDBname;
3126         if ( $wgDBprefix ) {
3127                 return "$wgDBname-$wgDBprefix";
3128         } else {
3129                 return $wgDBname;
3130         }
3131 }
3132
3133 /**
3134  * Split a wiki ID into DB name and table prefix
3135  */
3136 function wfSplitWikiID( $wiki ) {
3137         $bits = explode( '-', $wiki, 2 );
3138         if ( count( $bits ) < 2 ) {
3139                 $bits[] = '';
3140         }
3141         return $bits;
3142 }
3143
3144 /**
3145  * Get a Database object.
3146  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3147  *            master (for write queries), DB_SLAVE for potentially lagged read
3148  *            queries, or an integer >= 0 for a particular server.
3149  *
3150  * @param $groups Mixed: query groups. An array of group names that this query
3151  *                belongs to. May contain a single string if the query is only
3152  *                in one group.
3153  *
3154  * @param $wiki String: the wiki ID, or false for the current wiki
3155  *
3156  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3157  * will always return the same object, unless the underlying connection or load
3158  * balancer is manually destroyed.
3159  *
3160  * @return DatabaseBase
3161  */
3162 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3163         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3164 }
3165
3166 /**
3167  * Get a load balancer object.
3168  *
3169  * @param $wiki String: wiki ID, or false for the current wiki
3170  * @return LoadBalancer
3171  */
3172 function wfGetLB( $wiki = false ) {
3173         return wfGetLBFactory()->getMainLB( $wiki );
3174 }
3175
3176 /**
3177  * Get the load balancer factory object
3178  */
3179 function &wfGetLBFactory() {
3180         return LBFactory::singleton();
3181 }
3182
3183 /**
3184  * Find a file.
3185  * Shortcut for RepoGroup::singleton()->findFile()
3186  * @param $title String or Title object
3187  * @param $options Associative array of options:
3188  *     time:           requested time for an archived image, or false for the
3189  *                     current version. An image object will be returned which was
3190  *                     created at the specified time.
3191  *
3192  *     ignoreRedirect: If true, do not follow file redirects
3193  *
3194  *     private:        If true, return restricted (deleted) files if the current
3195  *                     user is allowed to view them. Otherwise, such files will not
3196  *                     be found.
3197  *
3198  *     bypassCache:    If true, do not use the process-local cache of File objects
3199  *
3200  * @return File, or false if the file does not exist
3201  */
3202 function wfFindFile( $title, $options = array() ) {
3203         return RepoGroup::singleton()->findFile( $title, $options );
3204 }
3205
3206 /**
3207  * Get an object referring to a locally registered file.
3208  * Returns a valid placeholder object if the file does not exist.
3209  * @param $title Title or String
3210  * @return File, or null if passed an invalid Title
3211  */
3212 function wfLocalFile( $title ) {
3213         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3214 }
3215
3216 /**
3217  * Should low-performance queries be disabled?
3218  *
3219  * @return Boolean
3220  */
3221 function wfQueriesMustScale() {
3222         global $wgMiserMode;
3223         return $wgMiserMode
3224                 || ( SiteStats::pages() > 100000
3225                 && SiteStats::edits() > 1000000
3226                 && SiteStats::users() > 10000 );
3227 }
3228
3229 /**
3230  * Get the path to a specified script file, respecting file
3231  * extensions; this is a wrapper around $wgScriptExtension etc.
3232  *
3233  * @param $script String: script filename, sans extension
3234  * @return String
3235  */
3236 function wfScript( $script = 'index' ) {
3237         global $wgScriptPath, $wgScriptExtension;
3238         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3239 }
3240
3241 /**
3242  * Get the script URL.
3243  *
3244  * @return script URL
3245  */
3246 function wfGetScriptUrl() {
3247         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3248                 #
3249                 # as it was called, minus the query string.
3250                 #
3251                 # Some sites use Apache rewrite rules to handle subdomains,
3252                 # and have PHP set up in a weird way that causes PHP_SELF
3253                 # to contain the rewritten URL instead of the one that the
3254                 # outside world sees.
3255                 #
3256                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3257                 # provides containing the "before" URL.
3258                 return $_SERVER['SCRIPT_NAME'];
3259         } else {
3260                 return $_SERVER['URL'];
3261         }
3262 }
3263
3264 /**
3265  * Convenience function converts boolean values into "true"
3266  * or "false" (string) values
3267  *
3268  * @param $value Boolean
3269  * @return String
3270  */
3271 function wfBoolToStr( $value ) {
3272         return $value ? 'true' : 'false';
3273 }
3274
3275 /**
3276  * Load an extension messages file
3277  * @deprecated in 1.16 (warnings in 1.18, removed in ?)
3278  */
3279 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
3280 }
3281
3282 /**
3283  * Get a platform-independent path to the null file, e.g.
3284  * /dev/null
3285  *
3286  * @return string
3287  */
3288 function wfGetNull() {
3289         return wfIsWindows()
3290                 ? 'NUL'
3291                 : '/dev/null';
3292 }
3293
3294 /**
3295  * Displays a maxlag error
3296  *
3297  * @param $host String: server that lags the most
3298  * @param $lag Integer: maxlag (actual)
3299  * @param $maxLag Integer: maxlag (requested)
3300  */
3301 function wfMaxlagError( $host, $lag, $maxLag ) {
3302         global $wgShowHostnames;
3303         header( 'HTTP/1.1 503 Service Unavailable' );
3304         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
3305         header( 'X-Database-Lag: ' . intval( $lag ) );
3306         header( 'Content-Type: text/plain' );
3307         if( $wgShowHostnames ) {
3308                 echo "Waiting for $host: $lag seconds lagged\n";
3309         } else {
3310                 echo "Waiting for a database server: $lag seconds lagged\n";
3311         }
3312 }
3313
3314 /**
3315  * Throws a warning that $function is deprecated
3316  * @param $function String
3317  * @return null
3318  */
3319 function wfDeprecated( $function ) {
3320         static $functionsWarned = array();
3321         if ( !isset( $functionsWarned[$function] ) ) {
3322                 $functionsWarned[$function] = true;
3323                 wfWarn( "Use of $function is deprecated.", 2 );
3324         }
3325 }
3326
3327 /**
3328  * Send a warning either to the debug log or in a PHP error depending on
3329  * $wgDevelopmentWarnings
3330  *
3331  * @param $msg String: message to send
3332  * @param $callerOffset Integer: number of itmes to go back in the backtrace to
3333  *        find the correct caller (1 = function calling wfWarn, ...)
3334  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3335  *        is true
3336  */
3337 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3338         $callers = wfDebugBacktrace();
3339         if( isset( $callers[$callerOffset + 1] ) ){
3340                 $callerfunc = $callers[$callerOffset + 1];
3341                 $callerfile = $callers[$callerOffset];
3342                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3343                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3344                 } else {
3345                         $file = '(internal function)';
3346                 }
3347                 $func = '';
3348                 if( isset( $callerfunc['class'] ) ) {
3349                         $func .= $callerfunc['class'] . '::';
3350                 }
3351                 if( isset( $callerfunc['function'] ) ) {
3352                         $func .= $callerfunc['function'];
3353                 }
3354                 $msg .= " [Called from $func in $file]";
3355         }
3356
3357         global $wgDevelopmentWarnings;
3358         if ( $wgDevelopmentWarnings ) {
3359                 trigger_error( $msg, $level );
3360         } else {
3361                 wfDebug( "$msg\n" );
3362         }
3363 }
3364
3365 /**
3366  * Sleep until the worst slave's replication lag is less than or equal to
3367  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
3368  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3369  * a no-op if there are no slaves.
3370  *
3371  * Every time the function has to wait for a slave, it will print a message to
3372  * that effect (and then sleep for a little while), so it's probably not best
3373  * to use this outside maintenance scripts in its present form.
3374  *
3375  * @param $maxLag Integer
3376  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3377  * @return null
3378  */
3379 function wfWaitForSlaves( $maxLag, $wiki = false ) {
3380         if( $maxLag ) {
3381                 $lb = wfGetLB( $wiki );
3382                 list( $host, $lag ) = $lb->getMaxLag( $wiki );
3383                 while( $lag > $maxLag ) {
3384                         wfSuppressWarnings();
3385                         $name = gethostbyaddr( $host );
3386                         wfRestoreWarnings();
3387                         if( $name !== false ) {
3388                                 $host = $name;
3389                         }
3390                         print "Waiting for $host (lagged $lag seconds)...\n";
3391                         sleep( $maxLag );
3392                         list( $host, $lag ) = $lb->getMaxLag();
3393                 }
3394         }
3395 }
3396
3397 /**
3398  * Output some plain text in command-line mode or in the installer (updaters.inc).
3399  * Do not use it in any other context, its behaviour is subject to change.
3400  */
3401 function wfOut( $s ) {
3402         global $wgCommandLineMode;
3403         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3404                 echo $s;
3405         } else {
3406                 echo htmlspecialchars( $s );
3407         }
3408         flush();
3409 }
3410
3411 /**
3412  * Count down from $n to zero on the terminal, with a one-second pause
3413  * between showing each number. For use in command-line scripts.
3414  */
3415 function wfCountDown( $n ) {
3416         for ( $i = $n; $i >= 0; $i-- ) {
3417                 if ( $i != $n ) {
3418                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3419                 }
3420                 echo $i;
3421                 flush();
3422                 if ( $i ) {
3423                         sleep( 1 );
3424                 }
3425         }
3426         echo "\n";
3427 }
3428
3429 /**
3430  * Generate a random 32-character hexadecimal token.
3431  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3432  *              characters before hashing.
3433  */
3434 function wfGenerateToken( $salt = '' ) {
3435         $salt = serialize( $salt );
3436         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3437 }
3438
3439 /**
3440  * Replace all invalid characters with -
3441  * @param $name Mixed: filename to process
3442  */
3443 function wfStripIllegalFilenameChars( $name ) {
3444         global $wgIllegalFileChars;
3445         $name = wfBaseName( $name );
3446         $name = preg_replace(
3447                 "/[^" . Title::legalChars() . "]" .
3448                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3449                         "/",
3450                 '-',
3451                 $name
3452         );
3453         return $name;
3454 }
3455
3456 /**
3457  * Insert array into another array after the specified *KEY*
3458  * @param $array Array: The array.
3459  * @param $insert Array: The array to insert.
3460  * @param $after Mixed: The key to insert after
3461  */
3462 function wfArrayInsertAfter( $array, $insert, $after ) {
3463         // Find the offset of the element to insert after.
3464         $keys = array_keys( $array );
3465         $offsetByKey = array_flip( $keys );
3466
3467         $offset = $offsetByKey[$after];
3468
3469         // Insert at the specified offset
3470         $before = array_slice( $array, 0, $offset + 1, true );
3471         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
3472
3473         $output = $before + $insert + $after;
3474
3475         return $output;
3476 }
3477
3478 /* Recursively converts the parameter (an object) to an array with the same data */
3479 function wfObjectToArray( $object, $recursive = true ) {
3480         $array = array();
3481         foreach ( get_object_vars( $object ) as $key => $value ) {
3482                 if ( is_object( $value ) && $recursive ) {
3483                         $value = wfObjectToArray( $value );
3484                 }
3485
3486                 $array[$key] = $value;
3487         }
3488
3489         return $array;
3490 }
3491
3492 /**
3493  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3494  * @return Integer value memory was set to.
3495  */
3496 function wfMemoryLimit() {
3497         global $wgMemoryLimit;
3498         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3499         if( $memlimit != -1 ) {
3500                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3501                 if( $conflimit == -1 ) {
3502                         wfDebug( "Removing PHP's memory limit\n" );
3503                         wfSuppressWarnings();
3504                         ini_set( 'memory_limit', $conflimit );
3505                         wfRestoreWarnings();
3506                         return $conflimit;
3507                 } elseif ( $conflimit > $memlimit ) {
3508                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3509                         wfSuppressWarnings();
3510                         ini_set( 'memory_limit', $conflimit );
3511                         wfRestoreWarnings();
3512                         return $conflimit;
3513                 }
3514         }
3515         return $memlimit;
3516 }
3517
3518 /**
3519  * Converts shorthand byte notation to integer form
3520  * @param $string String
3521  * @return Integer
3522  */
3523 function wfShorthandToInteger( $string = '' ) {
3524         $string = trim( $string );
3525         if( $string === '' ) {
3526                 return -1;
3527         }
3528         $last = $string[strlen( $string ) - 1];
3529         $val = intval( $string );
3530         switch( $last ) {
3531                 case 'g':
3532                 case 'G':
3533                         $val *= 1024;
3534                         // break intentionally missing
3535                 case 'm':
3536                 case 'M':
3537                         $val *= 1024;
3538                         // break intentionally missing
3539                 case 'k':
3540                 case 'K':
3541                         $val *= 1024;
3542         }
3543
3544         return $val;
3545 }
3546
3547 /**
3548  * Get the normalised IETF language tag
3549  * @param $code String: The language code.
3550  * @return $langCode String: The language code which complying with BCP 47 standards.
3551  */
3552 function wfBCP47( $code ) {
3553         $codeSegment = explode( '-', $code );
3554         foreach ( $codeSegment as $segNo => $seg ) {
3555                 if ( count( $codeSegment ) > 0 ) {
3556                         // ISO 3166 country code
3557                         if ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3558                                 $codeBCP[$segNo] = strtoupper( $seg );
3559                         // ISO 15924 script code
3560                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3561                                 $codeBCP[$segNo] = ucfirst( $seg );
3562                         // Use lowercase for other cases
3563                         } else {
3564                                 $codeBCP[$segNo] = strtolower( $seg );
3565                         }
3566                 } else {
3567                 // Use lowercase for single segment
3568                         $codeBCP[$segNo] = strtolower( $seg );
3569                 }
3570         }
3571         $langCode = implode( '-', $codeBCP );
3572         return $langCode;
3573 }
3574
3575 function wfArrayMap( $function, $input ) {
3576         $ret = array_map( $function, $input );
3577         foreach ( $ret as $key => $value ) {
3578                 $taint = istainted( $input[$key] );
3579                 if ( $taint ) {
3580                         taint( $ret[$key], $taint );
3581                 }
3582         }
3583         return $ret;
3584 }
3585
3586 /**
3587  * Returns the PackageRepository object for interaction with the package repository.
3588  *
3589  * TODO: Make the repository type also configurable.
3590  *
3591  * @since 1.17
3592  *
3593  * @return PackageRepository
3594  */
3595 function wfGetRepository() {
3596         global $wgRepositoryApiLocation;
3597         static $repository = false;
3598
3599         if ( $repository === false ) {
3600                 $repository = new DistributionRepository( $wgRepositoryApiLocation );
3601         }
3602
3603         return $repository;
3604 }