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 more or less support PHP 5.0.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( $keyA, $valueA ) = each( $a ) ) && ( list( $keyB, $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                         $protocol = $m[1];
 429                         $host = $m[2];
 430                         $port = intval( $m[3] );
 431                         $prefix = isset( $m[4] ) ? $m[4] : false;
 432                         $domain = AF_INET6;
 433                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 434                         $protocol = $m[1];
 435                         $host = $m[2];
 436                         if ( !IP::isIPv4( $host ) ) {
 437                                 $host = gethostbyname( $host );
 438                         }
 439                         $port = intval( $m[3] );
 440                         $prefix = isset( $m[4] ) ? $m[4] : false;
 441                         $domain = AF_INET;
 442                 } else {
 443                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 444                 }
 445                 // Clean it up for the multiplexer
 446                 if ( strval( $prefix ) !== '' ) {
 447                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 448                         if ( substr( $text, -1 ) != "\n" ) {
 449                                 $text .= "\n";
 450                         }
 451                 }
 452
 453                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 454                 if ( !$sock ) {
 455                         return;
 456                 }
 457                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 458                 socket_close( $sock );
 459         } else {
 460                 wfSuppressWarnings();
 461                 $exists = file_exists( $file );
 462                 $size = $exists ? filesize( $file ) : false;
 463                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 464                         error_log( $text, 3, $file );
 465                 }
 466                 wfRestoreWarnings();
 467         }
 468 }
 469
 470 /**
 471  * @todo document
 472  */
 473 function wfLogProfilingData() {
 474         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 475         global $wgProfiler, $wgProfileLimit, $wgUser;
 476         # Profiling must actually be enabled...
 477         if( is_null( $wgProfiler ) ) {
 478                 return;
 479         }
 480         # Get total page request time
 481         $now = wfTime();
 482         $elapsed = $now - $wgRequestTime;
 483         # Only show pages that longer than $wgProfileLimit time (default is 0)
 484         if( $elapsed <= $wgProfileLimit ) {
 485                 return;
 486         }
 487         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 488         $forward = '';
 489         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 490                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 491         }
 492         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 493                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 494         }
 495         if( !empty( $_SERVER['HTTP_FROM'] ) ) {
 496                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 497         }
 498         if( $forward ) {
 499                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 500         }
 501         // Don't unstub $wgUser at this late stage just for statistics purposes
 502         if( StubObject::isRealObject( $wgUser ) && $wgUser->isAnon() ) {
 503                 $forward .= ' anon';
 504         }
 505         $log = sprintf( "%s\t%04.3f\t%s\n",
 506                 gmdate( 'YmdHis' ), $elapsed,
 507                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 508         if ( $wgDebugLogFile != '' && ( $wgRequest->getVal( 'action' ) != 'raw' || $wgDebugRawPage ) ) {
 509                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 510         }
 511 }
 512
 513 /**
 514  * Check if the wiki read-only lock file is present. This can be used to lock
 515  * off editing functions, but doesn't guarantee that the database will not be
 516  * modified.
 517  * @return bool
 518  */
 519 function wfReadOnly() {
 520         global $wgReadOnlyFile, $wgReadOnly;
 521
 522         if ( !is_null( $wgReadOnly ) ) {
 523                 return (bool)$wgReadOnly;
 524         }
 525         if ( $wgReadOnlyFile == '' ) {
 526                 return false;
 527         }
 528         // Set $wgReadOnly for faster access next time
 529         if ( is_file( $wgReadOnlyFile ) ) {
 530                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 531         } else {
 532                 $wgReadOnly = false;
 533         }
 534         return (bool)$wgReadOnly;
 535 }
 536
 537 function wfReadOnlyReason() {
 538         global $wgReadOnly;
 539         wfReadOnly();
 540         return $wgReadOnly;
 541 }
 542
 543 /**
 544  * Return a Language object from $langcode
 545  * @param $langcode Mixed: either:
 546  *                  - a Language object
 547  *                  - code of the language to get the message for, if it is
 548  *                    a valid code create a language for that language, if
 549  *                    it is a string but not a valid code then make a basic
 550  *                    language object
 551  *                  - a boolean: if it's false then use the current users
 552  *                    language (as a fallback for the old parameter
 553  *                    functionality), or if it is true then use the wikis
 554  * @return Language object
 555  */
 556 function wfGetLangObj( $langcode = false ) {
 557         # Identify which language to get or create a language object for.
 558         # Using is_object here due to Stub objects.
 559         if( is_object( $langcode ) ) {
 560                 # Great, we already have the object (hopefully)!
 561                 return $langcode;
 562         }
 563
 564         global $wgContLang, $wgLanguageCode;
 565         if( $langcode === true || $langcode === $wgLanguageCode ) {
 566                 # $langcode is the language code of the wikis content language object.
 567                 # or it is a boolean and value is true
 568                 return $wgContLang;
 569         }
 570
 571         global $wgLang;
 572         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 573                 # $langcode is the language code of user language object.
 574                 # or it was a boolean and value is false
 575                 return $wgLang;
 576         }
 577
 578         $validCodes = array_keys( Language::getLanguageNames() );
 579         if( in_array( $langcode, $validCodes ) ) {
 580                 # $langcode corresponds to a valid language.
 581                 return Language::factory( $langcode );
 582         }
 583
 584         # $langcode is a string, but not a valid language code; use content language.
 585         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 586         return $wgContLang;
 587 }
 588
 589 /**
 590  * Use this instead of $wgContLang, when working with user interface.
 591  * User interface is currently hard coded according to wiki content language
 592  * in many ways, especially regarding to text direction. There is lots stuff
 593  * to fix, hence this function to keep the old behaviour unless the global
 594  * $wgBetterDirectionality is enabled (or removed when everything works).
 595  */
 596 function wfUILang() {
 597         global $wgBetterDirectionality;
 598         return wfGetLangObj( !$wgBetterDirectionality );
 599 }
 600
 601 /**
 602  * Get a message from anywhere, for the current user language.
 603  *
 604  * Use wfMsgForContent() instead if the message should NOT
 605  * change depending on the user preferences.
 606  *
 607  * @param $key String: lookup key for the message, usually
 608  *    defined in languages/Language.php
 609  *
 610  * This function also takes extra optional parameters (not
 611  * shown in the function definition), which can be used to
 612  * insert variable text into the predefined message.
 613  */
 614 function wfMsg( $key ) {
 615         $args = func_get_args();
 616         array_shift( $args );
 617         return wfMsgReal( $key, $args, true );
 618 }
 619
 620 /**
 621  * Same as above except doesn't transform the message
 622  */
 623 function wfMsgNoTrans( $key ) {
 624         $args = func_get_args();
 625         array_shift( $args );
 626         return wfMsgReal( $key, $args, true, false, false );
 627 }
 628
 629 /**
 630  * Get a message from anywhere, for the current global language
 631  * set with $wgLanguageCode.
 632  *
 633  * Use this if the message should NOT change dependent on the
 634  * language set in the user's preferences. This is the case for
 635  * most text written into logs, as well as link targets (such as
 636  * the name of the copyright policy page). Link titles, on the
 637  * other hand, should be shown in the UI language.
 638  *
 639  * Note that MediaWiki allows users to change the user interface
 640  * language in their preferences, but a single installation
 641  * typically only contains content in one language.
 642  *
 643  * Be wary of this distinction: If you use wfMsg() where you should
 644  * use wfMsgForContent(), a user of the software may have to
 645  * customize potentially hundreds of messages in
 646  * order to, e.g., fix a link in every possible language.
 647  *
 648  * @param $key String: lookup key for the message, usually
 649  *    defined in languages/Language.php
 650  */
 651 function wfMsgForContent( $key ) {
 652         global $wgForceUIMsgAsContentMsg;
 653         $args = func_get_args();
 654         array_shift( $args );
 655         $forcontent = true;
 656         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 657                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 658         {
 659                 $forcontent = false;
 660         }
 661         return wfMsgReal( $key, $args, true, $forcontent );
 662 }
 663
 664 /**
 665  * Same as above except doesn't transform the message
 666  */
 667 function wfMsgForContentNoTrans( $key ) {
 668         global $wgForceUIMsgAsContentMsg;
 669         $args = func_get_args();
 670         array_shift( $args );
 671         $forcontent = true;
 672         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 673                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 674         {
 675                 $forcontent = false;
 676         }
 677         return wfMsgReal( $key, $args, true, $forcontent, false );
 678 }
 679
 680 /**
 681  * Get a message from the language file, for the UI elements
 682  */
 683 function wfMsgNoDB( $key ) {
 684         $args = func_get_args();
 685         array_shift( $args );
 686         return wfMsgReal( $key, $args, false );
 687 }
 688
 689 /**
 690  * Get a message from the language file, for the content
 691  */
 692 function wfMsgNoDBForContent( $key ) {
 693         global $wgForceUIMsgAsContentMsg;
 694         $args = func_get_args();
 695         array_shift( $args );
 696         $forcontent = true;
 697         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 698                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 699         {
 700                 $forcontent = false;
 701         }
 702         return wfMsgReal( $key, $args, false, $forcontent );
 703 }
 704
 705
 706 /**
 707  * Really get a message
 708  * @param $key String: key to get.
 709  * @param $args
 710  * @param $useDB Boolean
 711  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 712  * @param $transform Boolean: Whether or not to transform the message.
 713  * @return String: the requested message.
 714  */
 715 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 716         wfProfileIn( __METHOD__ );
 717         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 718         $message = wfMsgReplaceArgs( $message, $args );
 719         wfProfileOut( __METHOD__ );
 720         return $message;
 721 }
 722
 723 /**
 724  * This function provides the message source for messages to be edited which are *not* stored in the database.
 725  * @param $key String:
 726  */
 727 function wfMsgWeirdKey( $key ) {
 728         $source = wfMsgGetKey( $key, false, true, false );
 729         if ( wfEmptyMsg( $key, $source ) ) {
 730                 return '';
 731         } else {
 732                 return $source;
 733         }
 734 }
 735
 736 /**
 737  * Fetch a message string value, but don't replace any keys yet.
 738  * @param $key String
 739  * @param $useDB Bool
 740  * @param $langCode String: Code of the language to get the message for, or
 741  *                  behaves as a content language switch if it is a boolean.
 742  * @param $transform Boolean: whether to parse magic words, etc.
 743  * @return string
 744  */
 745 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 746         global $wgMessageCache;
 747
 748         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 749
 750         if ( !is_object( $wgMessageCache ) ) {
 751                 throw new MWException( 'Trying to get message before message cache is initialised' );
 752         }
 753
 754         $message = $wgMessageCache->get( $key, $useDB, $langCode );
 755         if( $message === false ) {
 756                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 757         } elseif ( $transform ) {
 758                 $message = $wgMessageCache->transform( $message );
 759         }
 760         return $message;
 761 }
 762
 763 /**
 764  * Replace message parameter keys on the given formatted output.
 765  *
 766  * @param $message String
 767  * @param $args Array
 768  * @return string
 769  * @private
 770  */
 771 function wfMsgReplaceArgs( $message, $args ) {
 772         # Fix windows line-endings
 773         # Some messages are split with explode("\n", $msg)
 774         $message = str_replace( "\r", '', $message );
 775
 776         // Replace arguments
 777         if ( count( $args ) ) {
 778                 if ( is_array( $args[0] ) ) {
 779                         $args = array_values( $args[0] );
 780                 }
 781                 $replacementKeys = array();
 782                 foreach( $args as $n => $param ) {
 783                         $replacementKeys['$' . ( $n + 1 )] = $param;
 784                 }
 785                 $message = strtr( $message, $replacementKeys );
 786         }
 787
 788         return $message;
 789 }
 790
 791 /**
 792  * Return an HTML-escaped version of a message.
 793  * Parameter replacements, if any, are done *after* the HTML-escaping,
 794  * so parameters may contain HTML (eg links or form controls). Be sure
 795  * to pre-escape them if you really do want plaintext, or just wrap
 796  * the whole thing in htmlspecialchars().
 797  *
 798  * @param $key String
 799  * @param string ... parameters
 800  * @return string
 801  */
 802 function wfMsgHtml( $key ) {
 803         $args = func_get_args();
 804         array_shift( $args );
 805         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 806 }
 807
 808 /**
 809  * Return an HTML version of message
 810  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 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 wfMsgWikiHtml( $key ) {
 820         global $wgOut;
 821         $args = func_get_args();
 822         array_shift( $args );
 823         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 824 }
 825
 826 /**
 827  * Returns message in the requested format
 828  * @param $key String: key of the message
 829  * @param $options Array: processing rules. Can take the following options:
 830  *   <i>parse</i>: parses wikitext to HTML
 831  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 832  *       p's added by parser or tidy
 833  *   <i>escape</i>: filters message through htmlspecialchars
 834  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 835  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 836  *   <i>parsemag</i>: transform the message using magic phrases
 837  *   <i>content</i>: fetch message for content language instead of interface
 838  * Also can accept a single associative argument, of the form 'language' => 'xx':
 839  *   <i>language</i>: Language object or language code to fetch message for
 840  *       (overriden by <i>content</i>), its behaviour with parser, parseinline
 841  *       and parsemag is undefined.
 842  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 843  */
 844 function wfMsgExt( $key, $options ) {
 845         global $wgOut;
 846
 847         $args = func_get_args();
 848         array_shift( $args );
 849         array_shift( $args );
 850         $options = (array)$options;
 851
 852         foreach( $options as $arrayKey => $option ) {
 853                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 854                         # An unknown index, neither numeric nor "language"
 855                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 856                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 857                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 858                 'replaceafter', 'parsemag', 'content' ) ) ) {
 859                         # A numeric index with unknown value
 860                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 861                 }
 862         }
 863
 864         if( in_array( 'content', $options, true ) ) {
 865                 $forContent = true;
 866                 $langCode = true;
 867         } elseif( array_key_exists( 'language', $options ) ) {
 868                 $forContent = false;
 869                 $langCode = wfGetLangObj( $options['language'] );
 870         } else {
 871                 $forContent = false;
 872                 $langCode = false;
 873         }
 874
 875         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 876
 877         if( !in_array( 'replaceafter', $options, true ) ) {
 878                 $string = wfMsgReplaceArgs( $string, $args );
 879         }
 880
 881         if( in_array( 'parse', $options, true ) ) {
 882                 $string = $wgOut->parse( $string, true, !$forContent );
 883         } elseif ( in_array( 'parseinline', $options, true ) ) {
 884                 $string = $wgOut->parse( $string, true, !$forContent );
 885                 $m = array();
 886                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 887                         $string = $m[1];
 888                 }
 889         } elseif ( in_array( 'parsemag', $options, true ) ) {
 890                 global $wgMessageCache;
 891                 if ( isset( $wgMessageCache ) ) {
 892                         $string = $wgMessageCache->transform( $string,
 893                                 !$forContent,
 894                                 is_object( $langCode ) ? $langCode : null );
 895                 }
 896         }
 897
 898         if ( in_array( 'escape', $options, true ) ) {
 899                 $string = htmlspecialchars ( $string );
 900         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 901                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 902         }
 903
 904         if( in_array( 'replaceafter', $options, true ) ) {
 905                 $string = wfMsgReplaceArgs( $string, $args );
 906         }
 907
 908         return $string;
 909 }
 910
 911
 912 /**
 913  * Just like exit() but makes a note of it.
 914  * Commits open transactions except if the error parameter is set
 915  *
 916  * @deprecated Please return control to the caller or throw an exception
 917  */
 918 function wfAbruptExit( $error = false ) {
 919         static $called = false;
 920         if ( $called ) {
 921                 exit( -1 );
 922         }
 923         $called = true;
 924
 925         $bt = wfDebugBacktrace();
 926         if( $bt ) {
 927                 for( $i = 0; $i < count( $bt ); $i++ ) {
 928                         $file = isset( $bt[$i]['file'] ) ? $bt[$i]['file'] : 'unknown';
 929                         $line = isset( $bt[$i]['line'] ) ? $bt[$i]['line'] : 'unknown';
 930                         wfDebug( "WARNING: Abrupt exit in $file at line $line\n");
 931                 }
 932         } else {
 933                 wfDebug( "WARNING: Abrupt exit\n" );
 934         }
 935
 936         wfLogProfilingData();
 937
 938         if ( !$error ) {
 939                 wfGetLB()->closeAll();
 940         }
 941         exit( -1 );
 942 }
 943
 944 /**
 945  * @deprecated Please return control the caller or throw an exception
 946  */
 947 function wfErrorExit() {
 948         wfAbruptExit( true );
 949 }
 950
 951 /**
 952  * Print a simple message and die, returning nonzero to the shell if any.
 953  * Plain die() fails to return nonzero to the shell if you pass a string.
 954  * @param $msg String
 955  */
 956 function wfDie( $msg = '' ) {
 957         echo $msg;
 958         die( 1 );
 959 }
 960
 961 /**
 962  * Throw a debugging exception. This function previously once exited the process,
 963  * but now throws an exception instead, with similar results.
 964  *
 965  * @param $msg String: message shown when dieing.
 966  */
 967 function wfDebugDieBacktrace( $msg = '' ) {
 968         throw new MWException( $msg );
 969 }
 970
 971 /**
 972  * Fetch server name for use in error reporting etc.
 973  * Use real server name if available, so we know which machine
 974  * in a server farm generated the current page.
 975  * @return string
 976  */
 977 function wfHostname() {
 978         static $host;
 979         if ( is_null( $host ) ) {
 980                 if ( function_exists( 'posix_uname' ) ) {
 981                         // This function not present on Windows
 982                         $uname = @posix_uname();
 983                 } else {
 984                         $uname = false;
 985                 }
 986                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 987                         $host = $uname['nodename'];
 988                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
 989                         # Windows computer name
 990                         $host = getenv( 'COMPUTERNAME' );
 991                 } else {
 992                         # This may be a virtual server.
 993                         $host = $_SERVER['SERVER_NAME'];
 994                 }
 995         }
 996         return $host;
 997 }
 998
 999 /**
1000  * Returns a HTML comment with the elapsed time since request.
1001  * This method has no side effects.
1002  * @return string
1003  */
1004 function wfReportTime() {
1005         global $wgRequestTime, $wgShowHostnames;
1006
1007         $now = wfTime();
1008         $elapsed = $now - $wgRequestTime;
1009
1010         return $wgShowHostnames
1011                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1012                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1013 }
1014
1015 /**
1016  * Safety wrapper for debug_backtrace().
1017  *
1018  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1019  * murky circumstances, which may be triggered in part by stub objects
1020  * or other fancy talkin'.
1021  *
1022  * Will return an empty array if Zend Optimizer is detected or if
1023  * debug_backtrace is disabled, otherwise the output from
1024  * debug_backtrace() (trimmed).
1025  *
1026  * @return array of backtrace information
1027  */
1028 function wfDebugBacktrace() {
1029         static $disabled = null;
1030
1031         if( extension_loaded( 'Zend Optimizer' ) ) {
1032                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1033                 return array();
1034         }
1035
1036         if ( is_null( $disabled ) ) {
1037                 $disabled = false;
1038                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1039                 $functions = array_map( 'trim', $functions );
1040                 $functions = array_map( 'strtolower', $functions );
1041                 if ( in_array( 'debug_backtrace', $functions ) ) {
1042                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1043                         $disabled = true;
1044                 }
1045         }
1046         if ( $disabled ) {
1047                 return array();
1048         }
1049
1050         return array_slice( debug_backtrace(), 1 );
1051 }
1052
1053 function wfBacktrace() {
1054         global $wgCommandLineMode;
1055
1056         if ( $wgCommandLineMode ) {
1057                 $msg = '';
1058         } else {
1059                 $msg = "<ul>\n";
1060         }
1061         $backtrace = wfDebugBacktrace();
1062         foreach( $backtrace as $call ) {
1063                 if( isset( $call['file'] ) ) {
1064                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1065                         $file = $f[count( $f ) - 1];
1066                 } else {
1067                         $file = '-';
1068                 }
1069                 if( isset( $call['line'] ) ) {
1070                         $line = $call['line'];
1071                 } else {
1072                         $line = '-';
1073                 }
1074                 if ( $wgCommandLineMode ) {
1075                         $msg .= "$file line $line calls ";
1076                 } else {
1077                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1078                 }
1079                 if( !empty( $call['class'] ) ) {
1080                         $msg .= $call['class'] . '::';
1081                 }
1082                 $msg .= $call['function'] . '()';
1083
1084                 if ( $wgCommandLineMode ) {
1085                         $msg .= "\n";
1086                 } else {
1087                         $msg .= "</li>\n";
1088                 }
1089         }
1090         if ( $wgCommandLineMode ) {
1091                 $msg .= "\n";
1092         } else {
1093                 $msg .= "</ul>\n";
1094         }
1095
1096         return $msg;
1097 }
1098
1099
1100 /* Some generic result counters, pulled out of SearchEngine */
1101
1102
1103 /**
1104  * @todo document
1105  */
1106 function wfShowingResults( $offset, $limit ) {
1107         global $wgLang;
1108         return wfMsgExt(
1109                 'showingresults',
1110                 array( 'parseinline' ),
1111                 $wgLang->formatNum( $limit ),
1112                 $wgLang->formatNum( $offset + 1 )
1113         );
1114 }
1115
1116 /**
1117  * @todo document
1118  */
1119 function wfShowingResultsNum( $offset, $limit, $num ) {
1120         global $wgLang;
1121         return wfMsgExt(
1122                 'showingresultsnum',
1123                 array( 'parseinline' ),
1124                 $wgLang->formatNum( $limit ),
1125                 $wgLang->formatNum( $offset + 1 ),
1126                 $wgLang->formatNum( $num )
1127         );
1128 }
1129
1130 /**
1131  * Generate (prev x| next x) (20|50|100...) type links for paging
1132  * @param $offset String
1133  * @param $limit Integer
1134  * @param $link String
1135  * @param $query String: optional URL query parameter string
1136  * @param $atend Bool: optional param for specified if this is the last page
1137  */
1138 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1139         global $wgLang;
1140         $fmtLimit = $wgLang->formatNum( $limit );
1141         // FIXME: Why on earth this needs one message for the text and another one for tooltip??
1142         # Get prev/next link display text
1143         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1144         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1145         # Get prev/next link title text
1146         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1147         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1148         # Fetch the title object
1149         if( is_object( $link ) ) {
1150                 $title =& $link;
1151         } else {
1152                 $title = Title::newFromText( $link );
1153                 if( is_null( $title ) ) {
1154                         return false;
1155                 }
1156         }
1157         # Make 'previous' link
1158         if( 0 != $offset ) {
1159                 $po = $offset - $limit;
1160                 $po = max( $po, 0 );
1161                 $q = "limit={$limit}&offset={$po}";
1162                 if( $query != '' ) {
1163                         $q .= '&' . $query;
1164                 }
1165                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1166         } else {
1167                 $plink = $prev;
1168         }
1169         # Make 'next' link
1170         $no = $offset + $limit;
1171         $q = "limit={$limit}&offset={$no}";
1172         if( $query != '' ) {
1173                 $q .= '&' . $query;
1174         }
1175         if( $atend ) {
1176                 $nlink = $next;
1177         } else {
1178                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1179         }
1180         # Make links to set number of items per page
1181         $nums = $wgLang->pipeList( array(
1182                 wfNumLink( $offset, 20, $title, $query ),
1183                 wfNumLink( $offset, 50, $title, $query ),
1184                 wfNumLink( $offset, 100, $title, $query ),
1185                 wfNumLink( $offset, 250, $title, $query ),
1186                 wfNumLink( $offset, 500, $title, $query )
1187         ) );
1188         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1189 }
1190
1191 /**
1192  * Generate links for (20|50|100...) items-per-page links
1193  * @param $offset String
1194  * @param $limit Integer
1195  * @param $title Title
1196  * @param $query String: optional URL query parameter string
1197  */
1198 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1199         global $wgLang;
1200         if( $query == '' ) {
1201                 $q = '';
1202         } else {
1203                 $q = $query.'&';
1204         }
1205         $q .= "limit={$limit}&offset={$offset}";
1206         $fmtLimit = $wgLang->formatNum( $limit );
1207         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1208         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1209         return $s;
1210 }
1211
1212 /**
1213  * @todo document
1214  * @todo FIXME: we may want to blacklist some broken browsers
1215  *
1216  * @return bool Whereas client accept gzip compression
1217  */
1218 function wfClientAcceptsGzip() {
1219         if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1220                 # FIXME: we may want to blacklist some broken browsers
1221                 $m = array();
1222                 if( preg_match(
1223                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1224                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1225                         $m )
1226                 )
1227                 {
1228                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1229                                 return false;
1230                         }
1231                         wfDebug( " accepts gzip\n" );
1232                         return true;
1233                 }
1234         }
1235         return false;
1236 }
1237
1238 /**
1239  * Obtain the offset and limit values from the request string;
1240  * used in special pages
1241  *
1242  * @param $deflimit Default limit if none supplied
1243  * @param $optionname Name of a user preference to check against
1244  * @return array
1245  *
1246  */
1247 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1248         global $wgRequest;
1249         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1250 }
1251
1252 /**
1253  * Escapes the given text so that it may be output using addWikiText()
1254  * without any linking, formatting, etc. making its way through. This
1255  * is achieved by substituting certain characters with HTML entities.
1256  * As required by the callers, <nowiki> is not used. It currently does
1257  * not filter out characters which have special meaning only at the
1258  * start of a line, such as "*".
1259  *
1260  * @param $text String: text to be escaped
1261  */
1262 function wfEscapeWikiText( $text ) {
1263         $text = str_replace(
1264                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ), # }}
1265                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
1266                 htmlspecialchars( $text )
1267         );
1268         return $text;
1269 }
1270
1271 /**
1272  * @todo document
1273  */
1274 function wfQuotedPrintable( $string, $charset = '' ) {
1275         # Probably incomplete; see RFC 2045
1276         if( empty( $charset ) ) {
1277                 global $wgInputEncoding;
1278                 $charset = $wgInputEncoding;
1279         }
1280         $charset = strtoupper( $charset );
1281         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
1282
1283         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
1284         $replace = $illegal . '\t ?_';
1285         if( !preg_match( "/[$illegal]/", $string ) ) {
1286                 return $string;
1287         }
1288         $out = "=?$charset?Q?";
1289         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
1290         $out .= '?=';
1291         return $out;
1292 }
1293
1294
1295 /**
1296  * @todo document
1297  * @return float
1298  */
1299 function wfTime() {
1300         return microtime( true );
1301 }
1302
1303 /**
1304  * Sets dest to source and returns the original value of dest
1305  * If source is NULL, it just returns the value, it doesn't set the variable
1306  */
1307 function wfSetVar( &$dest, $source ) {
1308         $temp = $dest;
1309         if ( !is_null( $source ) ) {
1310                 $dest = $source;
1311         }
1312         return $temp;
1313 }
1314
1315 /**
1316  * As for wfSetVar except setting a bit
1317  */
1318 function wfSetBit( &$dest, $bit, $state = true ) {
1319         $temp = (bool)( $dest & $bit );
1320         if ( !is_null( $state ) ) {
1321                 if ( $state ) {
1322                         $dest |= $bit;
1323                 } else {
1324                         $dest &= ~$bit;
1325                 }
1326         }
1327         return $temp;
1328 }
1329
1330 /**
1331  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1332  * "days=7&limit=100". Options in the first array override options in the second.
1333  * Options set to "" will not be output.
1334  */
1335 function wfArrayToCGI( $array1, $array2 = null ) {
1336         if ( !is_null( $array2 ) ) {
1337                 $array1 = $array1 + $array2;
1338         }
1339
1340         $cgi = '';
1341         foreach ( $array1 as $key => $value ) {
1342                 if ( $value !== '' ) {
1343                         if ( $cgi != '' ) {
1344                                 $cgi .= '&';
1345                         }
1346                         if ( is_array( $value ) ) {
1347                                 $firstTime = true;
1348                                 foreach ( $value as $v ) {
1349                                         $cgi .= ( $firstTime ? '' : '&') .
1350                                                 urlencode( $key . '[]' ) . '=' .
1351                                                 urlencode( $v );
1352                                         $firstTime = false;
1353                                 }
1354                         } else {
1355                                 if ( is_object( $value ) ) {
1356                                         $value = $value->__toString();
1357                                 }
1358                                 $cgi .= urlencode( $key ) . '=' .
1359                                         urlencode( $value );
1360                         }
1361                 }
1362         }
1363         return $cgi;
1364 }
1365
1366 /**
1367  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1368  * its argument and returns the same string in array form.  This allows compa-
1369  * tibility with legacy functions that accept raw query strings instead of nice
1370  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1371  * valid query strings, or it will explode.
1372  *
1373  * @param $query String: query string
1374  * @return array Array version of input
1375  */
1376 function wfCgiToArray( $query ) {
1377         if( isset( $query[0] ) && $query[0] == '?' ) {
1378                 $query = substr( $query, 1 );
1379         }
1380         $bits = explode( '&', $query );
1381         $ret = array();
1382         foreach( $bits as $bit ) {
1383                 if( $bit === '' ) {
1384                         continue;
1385                 }
1386                 list( $key, $value ) = explode( '=', $bit );
1387                 $key = urldecode( $key );
1388                 $value = urldecode( $value );
1389                 $ret[$key] = $value;
1390         }
1391         return $ret;
1392 }
1393
1394 /**
1395  * Append a query string to an existing URL, which may or may not already
1396  * have query string parameters already. If so, they will be combined.
1397  *
1398  * @param $url String
1399  * @param $query Mixed: string or associative array
1400  * @return string
1401  */
1402 function wfAppendQuery( $url, $query ) {
1403         if ( is_array( $query ) ) {
1404                 $query = wfArrayToCGI( $query );
1405         }
1406         if( $query != '' ) {
1407                 if( false === strpos( $url, '?' ) ) {
1408                         $url .= '?';
1409                 } else {
1410                         $url .= '&';
1411                 }
1412                 $url .= $query;
1413         }
1414         return $url;
1415 }
1416
1417 /**
1418  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1419  * and $wgProto are correct.
1420  *
1421  * @todo this won't work with current-path-relative URLs
1422  * like "subdir/foo.html", etc.
1423  *
1424  * @param $url String: either fully-qualified or a local path + query
1425  * @return string Fully-qualified URL
1426  */
1427 function wfExpandUrl( $url ) {
1428         if( substr( $url, 0, 2 ) == '//' ) {
1429                 global $wgProto;
1430                 return $wgProto . ':' . $url;
1431         } elseif( substr( $url, 0, 1 ) == '/' ) {
1432                 global $wgServer;
1433                 return $wgServer . $url;
1434         } else {
1435                 return $url;
1436         }
1437 }
1438
1439 /**
1440  * This is obsolete, use SquidUpdate::purge()
1441  * @deprecated
1442  */
1443 function wfPurgeSquidServers( $urlArr ) {
1444         SquidUpdate::purge( $urlArr );
1445 }
1446
1447 /**
1448  * Windows-compatible version of escapeshellarg()
1449  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1450  * function puts single quotes in regardless of OS.
1451  *
1452  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1453  * earlier distro releases of PHP)
1454  */
1455 function wfEscapeShellArg( ) {
1456         wfInitShellLocale();
1457
1458         $args = func_get_args();
1459         $first = true;
1460         $retVal = '';
1461         foreach ( $args as $arg ) {
1462                 if ( !$first ) {
1463                         $retVal .= ' ';
1464                 } else {
1465                         $first = false;
1466                 }
1467
1468                 if ( wfIsWindows() ) {
1469                         // Escaping for an MSVC-style command line parser
1470                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1471                         // Double the backslashes before any double quotes. Escape the double quotes.
1472                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1473                         $arg = '';
1474                         $iteration = 0;
1475                         foreach ( $tokens as $token ) {
1476                                 if ( $iteration % 2 == 1 ) {
1477                                         // Delimiter, a double quote preceded by zero or more slashes
1478                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1479                                 } elseif ( $iteration % 4 == 2 ) {
1480                                         // ^ in $token will be outside quotes, need to be escaped
1481                                         $arg .= str_replace( '^', '^^', $token );
1482                                 } else { // $iteration % 4 == 0
1483                                         // ^ in $token will appear inside double quotes, so leave as is
1484                                         $arg .= $token;
1485                                 }
1486                                 $iteration++;
1487                         }
1488                         // Double the backslashes before the end of the string, because
1489                         // we will soon add a quote
1490                         $m = array();
1491                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1492                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1493                         }
1494
1495                         // Add surrounding quotes
1496                         $retVal .= '"' . $arg . '"';
1497                 } else {
1498                         $retVal .= escapeshellarg( $arg );
1499                 }
1500         }
1501         return $retVal;
1502 }
1503
1504 /**
1505  * wfMerge attempts to merge differences between three texts.
1506  * Returns true for a clean merge and false for failure or a conflict.
1507  */
1508 function wfMerge( $old, $mine, $yours, &$result ) {
1509         global $wgDiff3;
1510
1511         # This check may also protect against code injection in
1512         # case of broken installations.
1513         if( !$wgDiff3 || !file_exists( $wgDiff3 ) ) {
1514                 wfDebug( "diff3 not found\n" );
1515                 return false;
1516         }
1517
1518         # Make temporary files
1519         $td = wfTempDir();
1520         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1521         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1522         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1523
1524         fwrite( $oldtextFile, $old );
1525         fclose( $oldtextFile );
1526         fwrite( $mytextFile, $mine );
1527         fclose( $mytextFile );
1528         fwrite( $yourtextFile, $yours );
1529         fclose( $yourtextFile );
1530
1531         # Check for a conflict
1532         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1533                 wfEscapeShellArg( $mytextName ) . ' ' .
1534                 wfEscapeShellArg( $oldtextName ) . ' ' .
1535                 wfEscapeShellArg( $yourtextName );
1536         $handle = popen( $cmd, 'r' );
1537
1538         if( fgets( $handle, 1024 ) ) {
1539                 $conflict = true;
1540         } else {
1541                 $conflict = false;
1542         }
1543         pclose( $handle );
1544
1545         # Merge differences
1546         $cmd = $wgDiff3 . ' -a -e --merge ' .
1547                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1548         $handle = popen( $cmd, 'r' );
1549         $result = '';
1550         do {
1551                 $data = fread( $handle, 8192 );
1552                 if ( strlen( $data ) == 0 ) {
1553                         break;
1554                 }
1555                 $result .= $data;
1556         } while ( true );
1557         pclose( $handle );
1558         unlink( $mytextName );
1559         unlink( $oldtextName );
1560         unlink( $yourtextName );
1561
1562         if ( $result === '' && $old !== '' && !$conflict ) {
1563                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1564                 $conflict = true;
1565         }
1566         return !$conflict;
1567 }
1568
1569 /**
1570  * Returns unified plain-text diff of two texts.
1571  * Useful for machine processing of diffs.
1572  * @param $before String: the text before the changes.
1573  * @param $after String: the text after the changes.
1574  * @param $params String: command-line options for the diff command.
1575  * @return String: unified diff of $before and $after
1576  */
1577 function wfDiff( $before, $after, $params = '-u' ) {
1578         if ( $before == $after ) {
1579                 return '';
1580         }
1581
1582         global $wgDiff;
1583
1584         # This check may also protect against code injection in
1585         # case of broken installations.
1586         if( !file_exists( $wgDiff ) ) {
1587                 wfDebug( "diff executable not found\n" );
1588                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1589                 $format = new UnifiedDiffFormatter();
1590                 return $format->format( $diffs );
1591         }
1592
1593         # Make temporary files
1594         $td = wfTempDir();
1595         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1596         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1597
1598         fwrite( $oldtextFile, $before );
1599         fclose( $oldtextFile );
1600         fwrite( $newtextFile, $after );
1601         fclose( $newtextFile );
1602
1603         // Get the diff of the two files
1604         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1605
1606         $h = popen( $cmd, 'r' );
1607
1608         $diff = '';
1609
1610         do {
1611                 $data = fread( $h, 8192 );
1612                 if ( strlen( $data ) == 0 ) {
1613                         break;
1614                 }
1615                 $diff .= $data;
1616         } while ( true );
1617
1618         // Clean up
1619         pclose( $h );
1620         unlink( $oldtextName );
1621         unlink( $newtextName );
1622
1623         // Kill the --- and +++ lines. They're not useful.
1624         $diff_lines = explode( "\n", $diff );
1625         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1626                 unset( $diff_lines[0] );
1627         }
1628         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1629                 unset( $diff_lines[1] );
1630         }
1631
1632         $diff = implode( "\n", $diff_lines );
1633
1634         return $diff;
1635 }
1636
1637 /**
1638  * A wrapper around the PHP function var_export().
1639  * Either print it or add it to the regular output ($wgOut).
1640  *
1641  * @param $var A PHP variable to dump.
1642  */
1643 function wfVarDump( $var ) {
1644         global $wgOut;
1645         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1646         if ( headers_sent() || !@is_object( $wgOut ) ) {
1647                 print $s;
1648         } else {
1649                 $wgOut->addHTML( $s );
1650         }
1651 }
1652
1653 /**
1654  * Provide a simple HTTP error.
1655  */
1656 function wfHttpError( $code, $label, $desc ) {
1657         global $wgOut;
1658         $wgOut->disable();
1659         header( "HTTP/1.0 $code $label" );
1660         header( "Status: $code $label" );
1661         $wgOut->sendCacheControl();
1662
1663         header( 'Content-type: text/html; charset=utf-8' );
1664         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1665                 '<html><head><title>' .
1666                 htmlspecialchars( $label ) .
1667                 '</title></head><body><h1>' .
1668                 htmlspecialchars( $label ) .
1669                 '</h1><p>' .
1670                 nl2br( htmlspecialchars( $desc ) ) .
1671                 "</p></body></html>\n";
1672 }
1673
1674 /**
1675  * Clear away any user-level output buffers, discarding contents.
1676  *
1677  * Suitable for 'starting afresh', for instance when streaming
1678  * relatively large amounts of data without buffering, or wanting to
1679  * output image files without ob_gzhandler's compression.
1680  *
1681  * The optional $resetGzipEncoding parameter controls suppression of
1682  * the Content-Encoding header sent by ob_gzhandler; by default it
1683  * is left. See comments for wfClearOutputBuffers() for why it would
1684  * be used.
1685  *
1686  * Note that some PHP configuration options may add output buffer
1687  * layers which cannot be removed; these are left in place.
1688  *
1689  * @param $resetGzipEncoding Bool
1690  */
1691 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1692         if( $resetGzipEncoding ) {
1693                 // Suppress Content-Encoding and Content-Length
1694                 // headers from 1.10+s wfOutputHandler
1695                 global $wgDisableOutputCompression;
1696                 $wgDisableOutputCompression = true;
1697         }
1698         while( $status = ob_get_status() ) {
1699                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1700                         // Probably from zlib.output_compression or other
1701                         // PHP-internal setting which can't be removed.
1702                         //
1703                         // Give up, and hope the result doesn't break
1704                         // output behavior.
1705                         break;
1706                 }
1707                 if( !ob_end_clean() ) {
1708                         // Could not remove output buffer handler; abort now
1709                         // to avoid getting in some kind of infinite loop.
1710                         break;
1711                 }
1712                 if( $resetGzipEncoding ) {
1713                         if( $status['name'] == 'ob_gzhandler' ) {
1714                                 // Reset the 'Content-Encoding' field set by this handler
1715                                 // so we can start fresh.
1716                                 header( 'Content-Encoding:' );
1717                                 break;
1718                         }
1719                 }
1720         }
1721 }
1722
1723 /**
1724  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1725  *
1726  * Clear away output buffers, but keep the Content-Encoding header
1727  * produced by ob_gzhandler, if any.
1728  *
1729  * This should be used for HTTP 304 responses, where you need to
1730  * preserve the Content-Encoding header of the real result, but
1731  * also need to suppress the output of ob_gzhandler to keep to spec
1732  * and avoid breaking Firefox in rare cases where the headers and
1733  * body are broken over two packets.
1734  */
1735 function wfClearOutputBuffers() {
1736         wfResetOutputBuffers( false );
1737 }
1738
1739 /**
1740  * Converts an Accept-* header into an array mapping string values to quality
1741  * factors
1742  */
1743 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1744         # No arg means accept anything (per HTTP spec)
1745         if( !$accept ) {
1746                 return array( $def => 1.0 );
1747         }
1748
1749         $prefs = array();
1750
1751         $parts = explode( ',', $accept );
1752
1753         foreach( $parts as $part ) {
1754                 # FIXME: doesn't deal with params like 'text/html; level=1'
1755                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1756                 $match = array();
1757                 if( !isset( $qpart ) ) {
1758                         $prefs[$value] = 1.0;
1759                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1760                         $prefs[$value] = floatval( $match[1] );
1761                 }
1762         }
1763
1764         return $prefs;
1765 }
1766
1767 /**
1768  * Checks if a given MIME type matches any of the keys in the given
1769  * array. Basic wildcards are accepted in the array keys.
1770  *
1771  * Returns the matching MIME type (or wildcard) if a match, otherwise
1772  * NULL if no match.
1773  *
1774  * @param $type String
1775  * @param $avail Array
1776  * @return string
1777  * @private
1778  */
1779 function mimeTypeMatch( $type, $avail ) {
1780         if( array_key_exists( $type, $avail ) ) {
1781                 return $type;
1782         } else {
1783                 $parts = explode( '/', $type );
1784                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1785                         return $parts[0] . '/*';
1786                 } elseif( array_key_exists( '*/*', $avail ) ) {
1787                         return '*/*';
1788                 } else {
1789                         return null;
1790                 }
1791         }
1792 }
1793
1794 /**
1795  * Returns the 'best' match between a client's requested internet media types
1796  * and the server's list of available types. Each list should be an associative
1797  * array of type to preference (preference is a float between 0.0 and 1.0).
1798  * Wildcards in the types are acceptable.
1799  *
1800  * @param $cprefs Array: client's acceptable type list
1801  * @param $sprefs Array: server's offered types
1802  * @return string
1803  *
1804  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1805  * XXX: generalize to negotiate other stuff
1806  */
1807 function wfNegotiateType( $cprefs, $sprefs ) {
1808         $combine = array();
1809
1810         foreach( array_keys($sprefs) as $type ) {
1811                 $parts = explode( '/', $type );
1812                 if( $parts[1] != '*' ) {
1813                         $ckey = mimeTypeMatch( $type, $cprefs );
1814                         if( $ckey ) {
1815                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1816                         }
1817                 }
1818         }
1819
1820         foreach( array_keys( $cprefs ) as $type ) {
1821                 $parts = explode( '/', $type );
1822                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1823                         $skey = mimeTypeMatch( $type, $sprefs );
1824                         if( $skey ) {
1825                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1826                         }
1827                 }
1828         }
1829
1830         $bestq = 0;
1831         $besttype = null;
1832
1833         foreach( array_keys( $combine ) as $type ) {
1834                 if( $combine[$type] > $bestq ) {
1835                         $besttype = $type;
1836                         $bestq = $combine[$type];
1837                 }
1838         }
1839
1840         return $besttype;
1841 }
1842
1843 /**
1844  * Array lookup
1845  * Returns an array where the values in the first array are replaced by the
1846  * values in the second array with the corresponding keys
1847  *
1848  * @return array
1849  */
1850 function wfArrayLookup( $a, $b ) {
1851         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1852 }
1853
1854 /**
1855  * Convenience function; returns MediaWiki timestamp for the present time.
1856  * @return string
1857  */
1858 function wfTimestampNow() {
1859         # return NOW
1860         return wfTimestamp( TS_MW, time() );
1861 }
1862
1863 /**
1864  * Reference-counted warning suppression
1865  */
1866 function wfSuppressWarnings( $end = false ) {
1867         static $suppressCount = 0;
1868         static $originalLevel = false;
1869
1870         if ( $end ) {
1871                 if ( $suppressCount ) {
1872                         --$suppressCount;
1873                         if ( !$suppressCount ) {
1874                                 error_reporting( $originalLevel );
1875                         }
1876                 }
1877         } else {
1878                 if ( !$suppressCount ) {
1879                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE ) );
1880                 }
1881                 ++$suppressCount;
1882         }
1883 }
1884
1885 /**
1886  * Restore error level to previous value
1887  */
1888 function wfRestoreWarnings() {
1889         wfSuppressWarnings( true );
1890 }
1891
1892 # Autodetect, convert and provide timestamps of various types
1893
1894 /**
1895  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1896  */
1897 define( 'TS_UNIX', 0 );
1898
1899 /**
1900  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1901  */
1902 define( 'TS_MW', 1 );
1903
1904 /**
1905  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1906  */
1907 define( 'TS_DB', 2 );
1908
1909 /**
1910  * RFC 2822 format, for E-mail and HTTP headers
1911  */
1912 define( 'TS_RFC2822', 3 );
1913
1914 /**
1915  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1916  *
1917  * This is used by Special:Export
1918  */
1919 define( 'TS_ISO_8601', 4 );
1920
1921 /**
1922  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1923  *
1924  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1925  *       DateTime tag and page 36 for the DateTimeOriginal and
1926  *       DateTimeDigitized tags.
1927  */
1928 define( 'TS_EXIF', 5 );
1929
1930 /**
1931  * Oracle format time.
1932  */
1933 define( 'TS_ORACLE', 6 );
1934
1935 /**
1936  * Postgres format time.
1937  */
1938 define( 'TS_POSTGRES', 7 );
1939
1940 /**
1941  * DB2 format time
1942  */
1943 define( 'TS_DB2', 8 );
1944
1945 /**
1946  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
1947  *                    function will autodetect which format is supplied and act
1948  *                    accordingly.
1949  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
1950  * @return String: in the format specified in $outputtype
1951  */
1952 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1953         $uts = 0;
1954         $da = array();
1955         if ( $ts === 0 ) {
1956                 $uts = time();
1957         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1958                 # TS_DB
1959         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1960                 # TS_EXIF
1961         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
1962                 # TS_MW
1963         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
1964                 # TS_UNIX
1965                 $uts = $ts;
1966         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
1967                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
1968                 $uts = strtotime( preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1969                                 str_replace( '+00:00', 'UTC', $ts ) ) );
1970         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1971                 # TS_ISO_8601
1972         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
1973                 # TS_POSTGRES
1974         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
1975                 # TS_POSTGRES
1976         } elseif ( preg_match( '/^[A-Z][a-z]{2}, \d\d [A-Z][a-z]{2} \d{4} \d\d:\d\d:\d\d/', $ts ) ) {
1977                 # TS_RFC2822
1978                 $uts = strtotime( $ts );
1979         } else {
1980                 # Bogus value; fall back to the epoch...
1981                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1982                 $uts = 0;
1983         }
1984
1985         if (count( $da ) ) {
1986                 // Warning! gmmktime() acts oddly if the month or day is set to 0
1987                 // We may want to handle that explicitly at some point
1988                 $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
1989                         (int)$da[2], (int)$da[3], (int)$da[1] );
1990         }
1991
1992         switch( $outputtype ) {
1993                 case TS_UNIX:
1994                         return $uts;
1995                 case TS_MW:
1996                         return gmdate( 'YmdHis', $uts );
1997                 case TS_DB:
1998                         return gmdate( 'Y-m-d H:i:s', $uts );
1999                 case TS_ISO_8601:
2000                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
2001                 // This shouldn't ever be used, but is included for completeness
2002                 case TS_EXIF:
2003                         return gmdate( 'Y:m:d H:i:s', $uts );
2004                 case TS_RFC2822:
2005                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
2006                 case TS_ORACLE:
2007                         return gmdate( 'd-m-Y H:i:s.000000', $uts );
2008                         //return gmdate( 'd-M-y h.i.s A', $uts ) . ' +00:00';
2009                 case TS_POSTGRES:
2010                         return gmdate( 'Y-m-d H:i:s', $uts ) . ' GMT';
2011                 case TS_DB2:
2012                         return gmdate( 'Y-m-d H:i:s', $uts );
2013                 default:
2014                         throw new MWException( 'wfTimestamp() called with illegal output type.' );
2015         }
2016 }
2017
2018 /**
2019  * Return a formatted timestamp, or null if input is null.
2020  * For dealing with nullable timestamp columns in the database.
2021  * @param $outputtype Integer
2022  * @param $ts String
2023  * @return String
2024  */
2025 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2026         if( is_null( $ts ) ) {
2027                 return null;
2028         } else {
2029                 return wfTimestamp( $outputtype, $ts );
2030         }
2031 }
2032
2033 /**
2034  * Check if the operating system is Windows
2035  *
2036  * @return Bool: true if it's Windows, False otherwise.
2037  */
2038 function wfIsWindows() {
2039         if ( substr( php_uname(), 0, 7 ) == 'Windows' ) {
2040                 return true;
2041         } else {
2042                 return false;
2043         }
2044 }
2045
2046 /**
2047  * Swap two variables
2048  */
2049 function swap( &$x, &$y ) {
2050         $z = $x;
2051         $x = $y;
2052         $y = $z;
2053 }
2054
2055 function wfGetCachedNotice( $name ) {
2056         global $wgOut, $wgRenderHashAppend, $parserMemc;
2057         $fname = 'wfGetCachedNotice';
2058         wfProfileIn( $fname );
2059
2060         $needParse = false;
2061
2062         if( $name === 'default' ) {
2063                 // special case
2064                 global $wgSiteNotice;
2065                 $notice = $wgSiteNotice;
2066                 if( empty( $notice ) ) {
2067                         wfProfileOut( $fname );
2068                         return false;
2069                 }
2070         } else {
2071                 $notice = wfMsgForContentNoTrans( $name );
2072                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
2073                         wfProfileOut( $fname );
2074                         return( false );
2075                 }
2076         }
2077
2078         // Use the extra hash appender to let eg SSL variants separately cache.
2079         $key = wfMemcKey( $name . $wgRenderHashAppend );
2080         $cachedNotice = $parserMemc->get( $key );
2081         if( is_array( $cachedNotice ) ) {
2082                 if( md5( $notice ) == $cachedNotice['hash'] ) {
2083                         $notice = $cachedNotice['html'];
2084                 } else {
2085                         $needParse = true;
2086                 }
2087         } else {
2088                 $needParse = true;
2089         }
2090
2091         if( $needParse ) {
2092                 if( is_object( $wgOut ) ) {
2093                         $parsed = $wgOut->parse( $notice );
2094                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
2095                         $notice = $parsed;
2096                 } else {
2097                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' . "\n" );
2098                         $notice = '';
2099                 }
2100         }
2101         $notice = '<div id="localNotice">' .$notice . '</div>';
2102         wfProfileOut( $fname );
2103         return $notice;
2104 }
2105
2106 function wfGetNamespaceNotice() {
2107         global $wgTitle;
2108
2109         # Paranoia
2110         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) ) {
2111                 return '';
2112         }
2113
2114         $fname = 'wfGetNamespaceNotice';
2115         wfProfileIn( $fname );
2116
2117         $key = 'namespacenotice-' . $wgTitle->getNsText();
2118         $namespaceNotice = wfGetCachedNotice( $key );
2119         if ( $namespaceNotice && substr( $namespaceNotice, 0, 7 ) != '<p>&lt;' ) {
2120                 $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . '</div>';
2121         } else {
2122                 $namespaceNotice = '';
2123         }
2124
2125         wfProfileOut( $fname );
2126         return $namespaceNotice;
2127 }
2128
2129 function wfGetSiteNotice() {
2130         global $wgUser;
2131         $fname = 'wfGetSiteNotice';
2132         wfProfileIn( $fname );
2133         $siteNotice = '';
2134
2135         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
2136                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
2137                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
2138                 } else {
2139                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
2140                         if( !$anonNotice ) {
2141                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
2142                         } else {
2143                                 $siteNotice = $anonNotice;
2144                         }
2145                 }
2146                 if( !$siteNotice ) {
2147                         $siteNotice = wfGetCachedNotice( 'default' );
2148                 }
2149         }
2150
2151         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
2152         wfProfileOut( $fname );
2153         return $siteNotice;
2154 }
2155
2156 /**
2157  * BC wrapper for MimeMagic::singleton()
2158  * @deprecated
2159  */
2160 function &wfGetMimeMagic() {
2161         wfDeprecated( __FUNCTION__ );
2162         return MimeMagic::singleton();
2163 }
2164
2165 /**
2166  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2167  * TEMP environment variables are then checked in sequence, and if none are set
2168  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2169  * or C:\Windows\Temp for Windows and hope for the best.
2170  * It is common to call it with tempnam().
2171  *
2172  * NOTE: When possible, use instead the tmpfile() function to create
2173  * temporary files to avoid race conditions on file creation, etc.
2174  *
2175  * @return String
2176  */
2177 function wfTempDir() {
2178         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2179                 $tmp = getenv( $var );
2180                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2181                         return $tmp;
2182                 }
2183         }
2184         if( function_exists( 'sys_get_temp_dir' ) ) {
2185                 return sys_get_temp_dir();
2186         }
2187         # Usual defaults
2188         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2189 }
2190
2191 /**
2192  * Make directory, and make all parent directories if they don't exist
2193  *
2194  * @param $dir String: full path to directory to create
2195  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2196  * @param $caller String: optional caller param for debugging.
2197  * @return bool
2198  */
2199 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2200         global $wgDirectoryMode;
2201
2202         if ( !is_null( $caller ) ) {
2203                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2204         }
2205
2206         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2207                 return true;
2208         }
2209
2210         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2211
2212         if ( is_null( $mode ) ) {
2213                 $mode = $wgDirectoryMode;
2214         }
2215
2216         // Turn off the normal warning, we're doing our own below
2217         wfSuppressWarnings();
2218         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2219         wfRestoreWarnings();
2220
2221         if( !$ok ) {
2222                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2223                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2224         }
2225         return $ok;
2226 }
2227
2228 /**
2229  * Increment a statistics counter
2230  */
2231 function wfIncrStats( $key ) {
2232         global $wgStatsMethod;
2233
2234         if( $wgStatsMethod == 'udp' ) {
2235                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
2236                 static $socket;
2237                 if ( !$socket ) {
2238                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2239                         $statline = "stats/{$wgDBname} - 1 1 1 1 1 -total\n";
2240                         socket_sendto(
2241                                 $socket,
2242                                 $statline,
2243                                 strlen( $statline ),
2244                                 0,
2245                                 $wgUDPProfilerHost,
2246                                 $wgUDPProfilerPort
2247                         );
2248                 }
2249                 $statline = "stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
2250                 @socket_sendto(
2251                         $socket,
2252                         $statline,
2253                         strlen( $statline ),
2254                         0,
2255                         $wgUDPProfilerHost,
2256                         $wgUDPProfilerPort
2257                 );
2258         } elseif( $wgStatsMethod == 'cache' ) {
2259                 global $wgMemc;
2260                 $key = wfMemcKey( 'stats', $key );
2261                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2262                         $wgMemc->add( $key, 1 );
2263                 }
2264         } else {
2265                 // Disabled
2266         }
2267 }
2268
2269 /**
2270  * @param $nr Mixed: the number to format
2271  * @param $acc Integer: the number of digits after the decimal point, default 2
2272  * @param $round Boolean: whether or not to round the value, default true
2273  * @return float
2274  */
2275 function wfPercent( $nr, $acc = 2, $round = true ) {
2276         $ret = sprintf( "%.${acc}f", $nr );
2277         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2278 }
2279
2280 /**
2281  * Encrypt a username/password.
2282  *
2283  * @param $userid Integer: ID of the user
2284  * @param $password String: password of the user
2285  * @return String: hashed password
2286  * @deprecated Use User::crypt() or User::oldCrypt() instead
2287  */
2288 function wfEncryptPassword( $userid, $password ) {
2289         wfDeprecated(__FUNCTION__);
2290         # Just wrap around User::oldCrypt()
2291         return User::oldCrypt( $password, $userid );
2292 }
2293
2294 /**
2295  * Appends to second array if $value differs from that in $default
2296  */
2297 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2298         if ( is_null( $changed ) ) {
2299                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
2300         }
2301         if ( $default[$key] !== $value ) {
2302                 $changed[$key] = $value;
2303         }
2304 }
2305
2306 /**
2307  * Since wfMsg() and co suck, they don't return false if the message key they
2308  * looked up didn't exist but a XHTML string, this function checks for the
2309  * nonexistance of messages by looking at wfMsg() output
2310  *
2311  * @param $key      String: the message key looked up
2312  * @return Boolean True if the message *doesn't* exist.
2313  */
2314 function wfEmptyMsg( $key ) {
2315         global $wgMessageCache;
2316         return $wgMessageCache->get( $key, /*useDB*/true, /*content*/false ) === false;
2317 }
2318
2319 /**
2320  * Find out whether or not a mixed variable exists in a string
2321  *
2322  * @param $needle String
2323  * @param $str String
2324  * @return Boolean
2325  */
2326 function in_string( $needle, $str ) {
2327         return strpos( $str, $needle ) !== false;
2328 }
2329
2330 function wfSpecialList( $page, $details ) {
2331         global $wgContLang;
2332         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2333         return $page . $details;
2334 }
2335
2336 /**
2337  * Returns a regular expression of url protocols
2338  *
2339  * @return String
2340  */
2341 function wfUrlProtocols() {
2342         global $wgUrlProtocols;
2343
2344         static $retval = null;
2345         if ( !is_null( $retval ) ) {
2346                 return $retval;
2347         }
2348
2349         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2350         // with LocalSettings files from 1.5
2351         if ( is_array( $wgUrlProtocols ) ) {
2352                 $protocols = array();
2353                 foreach ( $wgUrlProtocols as $protocol ) {
2354                         $protocols[] = preg_quote( $protocol, '/' );
2355                 }
2356
2357                 $retval = implode( '|', $protocols );
2358         } else {
2359                 $retval = $wgUrlProtocols;
2360         }
2361         return $retval;
2362 }
2363
2364 /**
2365  * Safety wrapper around ini_get() for boolean settings.
2366  * The values returned from ini_get() are pre-normalized for settings
2367  * set via php.ini or php_flag/php_admin_flag... but *not*
2368  * for those set via php_value/php_admin_value.
2369  *
2370  * It's fairly common for people to use php_value instead of php_flag,
2371  * which can leave you with an 'off' setting giving a false positive
2372  * for code that just takes the ini_get() return value as a boolean.
2373  *
2374  * To make things extra interesting, setting via php_value accepts
2375  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2376  * Unrecognized values go false... again opposite PHP's own coercion
2377  * from string to bool.
2378  *
2379  * Luckily, 'properly' set settings will always come back as '0' or '1',
2380  * so we only have to worry about them and the 'improper' settings.
2381  *
2382  * I frickin' hate PHP... :P
2383  *
2384  * @param $setting String
2385  * @return Bool
2386  */
2387 function wfIniGetBool( $setting ) {
2388         $val = ini_get( $setting );
2389         // 'on' and 'true' can't have whitespace around them, but '1' can.
2390         return strtolower( $val ) == 'on'
2391                 || strtolower( $val ) == 'true'
2392                 || strtolower( $val ) == 'yes'
2393                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2394 }
2395
2396 /**
2397  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2398  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2399  *
2400  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2401  *                          should be omitted
2402  * @return Bool - Whether or not the extension is loaded
2403  */
2404 function wfDl( $extension ) {
2405         if( extension_loaded( $extension ) ) {
2406                 return true;
2407         }
2408
2409         $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2410                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2411
2412         if( $canDl ) {
2413                 wfSuppressWarnings();
2414                 dl( $extension . '.' . PHP_SHLIB_SUFFIX );
2415                 wfRestoreWarnings();
2416         }
2417         return extension_loaded( $extension );
2418 }
2419
2420 /**
2421  * Execute a shell command, with time and memory limits mirrored from the PHP
2422  * configuration if supported.
2423  * @param $cmd Command line, properly escaped for shell.
2424  * @param &$retval optional, will receive the program's exit code.
2425  *                 (non-zero is usually failure)
2426  * @return collected stdout as a string (trailing newlines stripped)
2427  */
2428 function wfShellExec( $cmd, &$retval = null ) {
2429         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2430
2431         static $disabled;
2432         if ( is_null( $disabled ) ) {
2433                 $disabled = false;
2434                 if( wfIniGetBool( 'safe_mode' ) ) {
2435                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2436                         $disabled = true;
2437                 }
2438                 $functions = explode( ',', ini_get( 'disable_functions' ) );
2439                 $functions = array_map( 'trim', $functions );
2440                 $functions = array_map( 'strtolower', $functions );
2441                 if ( in_array( 'passthru', $functions ) ) {
2442                         wfDebug( "passthru is in disabled_functions\n" );
2443                         $disabled = true;
2444                 }
2445         }
2446         if ( $disabled ) {
2447                 $retval = 1;
2448                 return 'Unable to run external programs in safe mode.';
2449         }
2450
2451         wfInitShellLocale();
2452
2453         if ( php_uname( 's' ) == 'Linux' ) {
2454                 $time = intval( $wgMaxShellTime );
2455                 $mem = intval( $wgMaxShellMemory );
2456                 $filesize = intval( $wgMaxShellFileSize );
2457
2458                 if ( $time > 0 && $mem > 0 ) {
2459                         $script = "$IP/bin/ulimit4.sh";
2460                         if ( is_executable( $script ) ) {
2461                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2462                         }
2463                 }
2464         } elseif ( php_uname( 's' ) == 'Windows NT' &&
2465                 version_compare( PHP_VERSION, '5.3.0', '<' ) )
2466         {
2467                 # This is a hack to work around PHP's flawed invocation of cmd.exe
2468                 # http://news.php.net/php.internals/21796
2469                 # Which is fixed in 5.3.0 :)
2470                 $cmd = '"' . $cmd . '"';
2471         }
2472         wfDebug( "wfShellExec: $cmd\n" );
2473
2474         $retval = 1; // error by default?
2475         ob_start();
2476         passthru( $cmd, $retval );
2477         $output = ob_get_contents();
2478         ob_end_clean();
2479
2480         if ( $retval == 127 ) {
2481                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2482         }
2483         return $output;
2484 }
2485
2486 /**
2487  * Workaround for http://bugs.php.net/bug.php?id=45132
2488  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2489  */
2490 function wfInitShellLocale() {
2491         static $done = false;
2492         if ( $done ) {
2493                 return;
2494         }
2495         $done = true;
2496         global $wgShellLocale;
2497         if ( !wfIniGetBool( 'safe_mode' ) ) {
2498                 putenv( "LC_CTYPE=$wgShellLocale" );
2499                 setlocale( LC_CTYPE, $wgShellLocale );
2500         }
2501 }
2502
2503 /**
2504  * This function works like "use VERSION" in Perl, the program will die with a
2505  * backtrace if the current version of PHP is less than the version provided
2506  *
2507  * This is useful for extensions which due to their nature are not kept in sync
2508  * with releases, and might depend on other versions of PHP than the main code
2509  *
2510  * Note: PHP might die due to parsing errors in some cases before it ever
2511  *       manages to call this function, such is life
2512  *
2513  * @see perldoc -f use
2514  *
2515  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2516  *                 a float
2517  */
2518 function wfUsePHP( $req_ver ) {
2519         $php_ver = PHP_VERSION;
2520
2521         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2522                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2523         }
2524 }
2525
2526 /**
2527  * This function works like "use VERSION" in Perl except it checks the version
2528  * of MediaWiki, the program will die with a backtrace if the current version
2529  * of MediaWiki is less than the version provided.
2530  *
2531  * This is useful for extensions which due to their nature are not kept in sync
2532  * with releases
2533  *
2534  * @see perldoc -f use
2535  *
2536  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2537  *                 a float
2538  */
2539 function wfUseMW( $req_ver ) {
2540         global $wgVersion;
2541
2542         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2543                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2544         }
2545 }
2546
2547 /**
2548  * Return the final portion of a pathname.
2549  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2550  * http://bugs.php.net/bug.php?id=33898
2551  *
2552  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2553  * We'll consider it so always, as we don't want \s in our Unix paths either.
2554  *
2555  * @param $path String
2556  * @param $suffix String: to remove if present
2557  * @return String
2558  */
2559 function wfBaseName( $path, $suffix = '' ) {
2560         $encSuffix = ( $suffix == '' )
2561                 ? ''
2562                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2563         $matches = array();
2564         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2565                 return $matches[1];
2566         } else {
2567                 return '';
2568         }
2569 }
2570
2571 /**
2572  * Generate a relative path name to the given file.
2573  * May explode on non-matching case-insensitive paths,
2574  * funky symlinks, etc.
2575  *
2576  * @param $path String: absolute destination path including target filename
2577  * @param $from String: Absolute source path, directory only
2578  * @return String
2579  */
2580 function wfRelativePath( $path, $from ) {
2581         // Normalize mixed input on Windows...
2582         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2583         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2584
2585         // Trim trailing slashes -- fix for drive root
2586         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2587         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2588
2589         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2590         $against = explode( DIRECTORY_SEPARATOR, $from );
2591
2592         if( $pieces[0] !== $against[0] ) {
2593                 // Non-matching Windows drive letters?
2594                 // Return a full path.
2595                 return $path;
2596         }
2597
2598         // Trim off common prefix
2599         while( count( $pieces ) && count( $against )
2600                 && $pieces[0] == $against[0] ) {
2601                 array_shift( $pieces );
2602                 array_shift( $against );
2603         }
2604
2605         // relative dots to bump us to the parent
2606         while( count( $against ) ) {
2607                 array_unshift( $pieces, '..' );
2608                 array_shift( $against );
2609         }
2610
2611         array_push( $pieces, wfBaseName( $path ) );
2612
2613         return implode( DIRECTORY_SEPARATOR, $pieces );
2614 }
2615
2616 /**
2617  * Backwards array plus for people who haven't bothered to read the PHP manual
2618  * XXX: will not darn your socks for you.
2619  *
2620  * @param $array1 Array
2621  * @param [$array2, [...]] Arrays
2622  * @return Array
2623  */
2624 function wfArrayMerge( $array1/* ... */ ) {
2625         $args = func_get_args();
2626         $args = array_reverse( $args, true );
2627         $out = array();
2628         foreach ( $args as $arg ) {
2629                 $out += $arg;
2630         }
2631         return $out;
2632 }
2633
2634 /**
2635  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
2636  * e.g.
2637  *      wfMergeErrorArrays(
2638  *              array( array( 'x' ) ),
2639  *              array( array( 'x', '2' ) ),
2640  *              array( array( 'x' ) ),
2641  *              array( array( 'y') )
2642  *      );
2643  * returns:
2644  *              array(
2645  *              array( 'x', '2' ),
2646  *              array( 'x' ),
2647  *              array( 'y' )
2648  *      )
2649  */
2650 function wfMergeErrorArrays( /*...*/ ) {
2651         $args = func_get_args();
2652         $out = array();
2653         foreach ( $args as $errors ) {
2654                 foreach ( $errors as $params ) {
2655                         # FIXME: sometimes get nested arrays for $params,
2656                         # which leads to E_NOTICEs
2657                         $spec = implode( "\t", $params );
2658                         $out[$spec] = $params;
2659                 }
2660         }
2661         return array_values( $out );
2662 }
2663
2664 /**
2665  * parse_url() work-alike, but non-broken.  Differences:
2666  *
2667  * 1) Does not raise warnings on bad URLs (just returns false)
2668  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2669  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2670  *
2671  * @param $url String: a URL to parse
2672  * @return Array: bits of the URL in an associative array, per PHP docs
2673  */
2674 function wfParseUrl( $url ) {
2675         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2676         wfSuppressWarnings();
2677         $bits = parse_url( $url );
2678         wfRestoreWarnings();
2679         if ( !$bits ) {
2680                 return false;
2681         }
2682
2683         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2684         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2685                 $bits['delimiter'] = '://';
2686         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2687                 $bits['delimiter'] = ':';
2688                 // parse_url detects for news: and mailto: the host part of an url as path
2689                 // We have to correct this wrong detection
2690                 if ( isset( $bits['path'] ) ) {
2691                         $bits['host'] = $bits['path'];
2692                         $bits['path'] = '';
2693                 }
2694         } else {
2695                 return false;
2696         }
2697
2698         return $bits;
2699 }
2700
2701 /**
2702  * Make a URL index, appropriate for the el_index field of externallinks.
2703  */
2704 function wfMakeUrlIndex( $url ) {
2705         $bits = wfParseUrl( $url );
2706
2707         // Reverse the labels in the hostname, convert to lower case
2708         // For emails reverse domainpart only
2709         if ( $bits['scheme'] == 'mailto' ) {
2710                 $mailparts = explode( '@', $bits['host'], 2 );
2711                 if ( count( $mailparts ) === 2 ) {
2712                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2713                 } else {
2714                         // No domain specified, don't mangle it
2715                         $domainpart = '';
2716                 }
2717                 $reversedHost = $domainpart . '@' . $mailparts[0];
2718         } else {
2719                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2720         }
2721         // Add an extra dot to the end
2722         // Why? Is it in wrong place in mailto links?
2723         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2724                 $reversedHost .= '.';
2725         }
2726         // Reconstruct the pseudo-URL
2727         $prot = $bits['scheme'];
2728         $index = $prot . $bits['delimiter'] . $reversedHost;
2729         // Leave out user and password. Add the port, path, query and fragment
2730         if ( isset( $bits['port'] ) ) {
2731                 $index .= ':' . $bits['port'];
2732         }
2733         if ( isset( $bits['path'] ) ) {
2734                 $index .= $bits['path'];
2735         } else {
2736                 $index .= '/';
2737         }
2738         if ( isset( $bits['query'] ) ) {
2739                 $index .= '?' . $bits['query'];
2740         }
2741         if ( isset( $bits['fragment'] ) ) {
2742                 $index .= '#' . $bits['fragment'];
2743         }
2744         return $index;
2745 }
2746
2747 /**
2748  * Do any deferred updates and clear the list
2749  * TODO: This could be in Wiki.php if that class made any sense at all
2750  */
2751 function wfDoUpdates() {
2752         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2753         foreach ( $wgDeferredUpdateList as $update ) {
2754                 $update->doUpdate();
2755         }
2756         foreach ( $wgPostCommitUpdateList as $update ) {
2757                 $update->doUpdate();
2758         }
2759         $wgDeferredUpdateList = array();
2760         $wgPostCommitUpdateList = array();
2761 }
2762
2763 /**
2764  * Convert an arbitrarily-long digit string from one numeric base
2765  * to another, optionally zero-padding to a minimum column width.
2766  *
2767  * Supports base 2 through 36; digit values 10-36 are represented
2768  * as lowercase letters a-z. Input is case-insensitive.
2769  *
2770  * @param $input String: of digits
2771  * @param $sourceBase Integer: 2-36
2772  * @param $destBase Integer: 2-36
2773  * @param $pad Integer: 1 or greater
2774  * @param $lowercase Boolean
2775  * @return String or false on invalid input
2776  */
2777 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2778         $input = strval( $input );
2779         if( $sourceBase < 2 ||
2780                 $sourceBase > 36 ||
2781                 $destBase < 2 ||
2782                 $destBase > 36 ||
2783                 $pad < 1 ||
2784                 $sourceBase != intval( $sourceBase ) ||
2785                 $destBase != intval( $destBase ) ||
2786                 $pad != intval( $pad ) ||
2787                 !is_string( $input ) ||
2788                 $input == '' ) {
2789                 return false;
2790         }
2791         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2792         $inDigits = array();
2793         $outChars = '';
2794
2795         // Decode and validate input string
2796         $input = strtolower( $input );
2797         for( $i = 0; $i < strlen( $input ); $i++ ) {
2798                 $n = strpos( $digitChars, $input{$i} );
2799                 if( $n === false || $n > $sourceBase ) {
2800                         return false;
2801                 }
2802                 $inDigits[] = $n;
2803         }
2804
2805         // Iterate over the input, modulo-ing out an output digit
2806         // at a time until input is gone.
2807         while( count( $inDigits ) ) {
2808                 $work = 0;
2809                 $workDigits = array();
2810
2811                 // Long division...
2812                 foreach( $inDigits as $digit ) {
2813                         $work *= $sourceBase;
2814                         $work += $digit;
2815
2816                         if( $work < $destBase ) {
2817                                 // Gonna need to pull another digit.
2818                                 if( count( $workDigits ) ) {
2819                                         // Avoid zero-padding; this lets us find
2820                                         // the end of the input very easily when
2821                                         // length drops to zero.
2822                                         $workDigits[] = 0;
2823                                 }
2824                         } else {
2825                                 // Finally! Actual division!
2826                                 $workDigits[] = intval( $work / $destBase );
2827
2828                                 // Isn't it annoying that most programming languages
2829                                 // don't have a single divide-and-remainder operator,
2830                                 // even though the CPU implements it that way?
2831                                 $work = $work % $destBase;
2832                         }
2833                 }
2834
2835                 // All that division leaves us with a remainder,
2836                 // which is conveniently our next output digit.
2837                 $outChars .= $digitChars[$work];
2838
2839                 // And we continue!
2840                 $inDigits = $workDigits;
2841         }
2842
2843         while( strlen( $outChars ) < $pad ) {
2844                 $outChars .= '0';
2845         }
2846
2847         return strrev( $outChars );
2848 }
2849
2850 /**
2851  * Create an object with a given name and an array of construct parameters
2852  * @param $name String
2853  * @param $p Array: parameters
2854  */
2855 function wfCreateObject( $name, $p ) {
2856         $p = array_values( $p );
2857         switch ( count( $p ) ) {
2858                 case 0:
2859                         return new $name;
2860                 case 1:
2861                         return new $name( $p[0] );
2862                 case 2:
2863                         return new $name( $p[0], $p[1] );
2864                 case 3:
2865                         return new $name( $p[0], $p[1], $p[2] );
2866                 case 4:
2867                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2868                 case 5:
2869                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2870                 case 6:
2871                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2872                 default:
2873                         throw new MWException( 'Too many arguments to construtor in wfCreateObject' );
2874         }
2875 }
2876
2877 function wfHttpOnlySafe() {
2878         global $wgHttpOnlyBlacklist;
2879         if( !version_compare( '5.2', PHP_VERSION, '<' ) ) {
2880                 return false;
2881         }
2882
2883         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2884                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2885                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2886                                 return false;
2887                         }
2888                 }
2889         }
2890
2891         return true;
2892 }
2893
2894 /**
2895  * Initialise php session
2896  */
2897 function wfSetupSession() {
2898         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
2899                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
2900         if( $wgSessionsInMemcached ) {
2901                 require_once( 'MemcachedSessions.php' );
2902         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
2903                 # Only set this if $wgSessionHandler isn't null and session.save_handler
2904                 # hasn't already been set to the desired value (that causes errors)
2905                 ini_set( 'session.save_handler', $wgSessionHandler );
2906         }
2907         $httpOnlySafe = wfHttpOnlySafe();
2908         wfDebugLog( 'cookie',
2909                 'session_set_cookie_params: "' . implode( '", "',
2910                         array(
2911                                 0,
2912                                 $wgCookiePath,
2913                                 $wgCookieDomain,
2914                                 $wgCookieSecure,
2915                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2916         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2917                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2918         } else {
2919                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2920                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2921         }
2922         session_cache_limiter( 'private, must-revalidate' );
2923         wfSuppressWarnings();
2924         session_start();
2925         wfRestoreWarnings();
2926 }
2927
2928 /**
2929  * Get an object from the precompiled serialized directory
2930  *
2931  * @return Mixed: the variable on success, false on failure
2932  */
2933 function wfGetPrecompiledData( $name ) {
2934         global $IP;
2935
2936         $file = "$IP/serialized/$name";
2937         if ( file_exists( $file ) ) {
2938                 $blob = file_get_contents( $file );
2939                 if ( $blob ) {
2940                         return unserialize( $blob );
2941                 }
2942         }
2943         return false;
2944 }
2945
2946 function wfGetCaller( $level = 2 ) {
2947         $backtrace = wfDebugBacktrace();
2948         if ( isset( $backtrace[$level] ) ) {
2949                 return wfFormatStackFrame( $backtrace[$level] );
2950         } else {
2951                 $caller = 'unknown';
2952         }
2953         return $caller;
2954 }
2955
2956 /**
2957  * Return a string consisting of callers in the stack. Useful sometimes
2958  * for profiling specific points.
2959  *
2960  * @param $limit The maximum depth of the stack frame to return, or false for
2961  *               the entire stack.
2962  */
2963 function wfGetAllCallers( $limit = 3 ) {
2964         $trace = array_reverse( wfDebugBacktrace() );
2965         if ( !$limit || $limit > count( $trace ) - 1 ) {
2966                 $limit = count( $trace ) - 1;
2967         }
2968         $trace = array_slice( $trace, -$limit - 1, $limit );
2969         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
2970 }
2971
2972 /**
2973  * Return a string representation of frame
2974  */
2975 function wfFormatStackFrame( $frame ) {
2976         return isset( $frame['class'] ) ?
2977                 $frame['class'] . '::' . $frame['function'] :
2978                 $frame['function'];
2979 }
2980
2981 /**
2982  * Get a cache key
2983  */
2984 function wfMemcKey( /*... */ ) {
2985         $args = func_get_args();
2986         $key = wfWikiID() . ':' . implode( ':', $args );
2987         $key = str_replace( ' ', '_', $key );
2988         return $key;
2989 }
2990
2991 /**
2992  * Get a cache key for a foreign DB
2993  */
2994 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2995         $args = array_slice( func_get_args(), 2 );
2996         if ( $prefix ) {
2997                 $key = "$db-$prefix:" . implode( ':', $args );
2998         } else {
2999                 $key = $db . ':' . implode( ':', $args );
3000         }
3001         return $key;
3002 }
3003
3004 /**
3005  * Get an ASCII string identifying this wiki
3006  * This is used as a prefix in memcached keys
3007  */
3008 function wfWikiID() {
3009         global $wgDBprefix, $wgDBname;
3010         if ( $wgDBprefix ) {
3011                 return "$wgDBname-$wgDBprefix";
3012         } else {
3013                 return $wgDBname;
3014         }
3015 }
3016
3017 /**
3018  * Split a wiki ID into DB name and table prefix
3019  */
3020 function wfSplitWikiID( $wiki ) {
3021         $bits = explode( '-', $wiki, 2 );
3022         if ( count( $bits ) < 2 ) {
3023                 $bits[] = '';
3024         }
3025         return $bits;
3026 }
3027
3028 /**
3029  * Get a Database object.
3030  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3031  *            master (for write queries), DB_SLAVE for potentially lagged read
3032  *            queries, or an integer >= 0 for a particular server.
3033  *
3034  * @param $groups Mixed: query groups. An array of group names that this query
3035  *                belongs to. May contain a single string if the query is only
3036  *                in one group.
3037  *
3038  * @param $wiki String: the wiki ID, or false for the current wiki
3039  *
3040  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3041  * will always return the same object, unless the underlying connection or load
3042  * balancer is manually destroyed.
3043  *
3044  * @return DatabaseBase
3045  */
3046 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3047         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3048 }
3049
3050 /**
3051  * Get a load balancer object.
3052  *
3053  * @param $wiki String: wiki ID, or false for the current wiki
3054  * @return LoadBalancer
3055  */
3056 function wfGetLB( $wiki = false ) {
3057         return wfGetLBFactory()->getMainLB( $wiki );
3058 }
3059
3060 /**
3061  * Get the load balancer factory object
3062  */
3063 function &wfGetLBFactory() {
3064         return LBFactory::singleton();
3065 }
3066
3067 /**
3068  * Find a file.
3069  * Shortcut for RepoGroup::singleton()->findFile()
3070  * @param $title Either a string or Title object
3071  * @param $options Associative array of options:
3072  *     time:           requested time for an archived image, or false for the
3073  *                     current version. An image object will be returned which was
3074  *                     created at the specified time.
3075  *
3076  *     ignoreRedirect: If true, do not follow file redirects
3077  *
3078  *     private:        If true, return restricted (deleted) files if the current
3079  *                     user is allowed to view them. Otherwise, such files will not
3080  *                     be found.
3081  *
3082  *     bypassCache:    If true, do not use the process-local cache of File objects
3083  *
3084  * @return File, or false if the file does not exist
3085  */
3086 function wfFindFile( $title, $options = array() ) {
3087         return RepoGroup::singleton()->findFile( $title, $options );
3088 }
3089
3090 /**
3091  * Get an object referring to a locally registered file.
3092  * Returns a valid placeholder object if the file does not exist.
3093  * @param $title Either a string or Title object
3094  * @return File, or null if passed an invalid Title
3095  */
3096 function wfLocalFile( $title ) {
3097         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3098 }
3099
3100 /**
3101  * Should low-performance queries be disabled?
3102  *
3103  * @return Boolean
3104  */
3105 function wfQueriesMustScale() {
3106         global $wgMiserMode;
3107         return $wgMiserMode
3108                 || ( SiteStats::pages() > 100000
3109                 && SiteStats::edits() > 1000000
3110                 && SiteStats::users() > 10000 );
3111 }
3112
3113 /**
3114  * Get the path to a specified script file, respecting file
3115  * extensions; this is a wrapper around $wgScriptExtension etc.
3116  *
3117  * @param $script String: script filename, sans extension
3118  * @return String
3119  */
3120 function wfScript( $script = 'index' ) {
3121         global $wgScriptPath, $wgScriptExtension;
3122         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3123 }
3124
3125 /**
3126  * Get the script URL.
3127  *
3128  * @return script URL
3129  */
3130 function wfGetScriptUrl() {
3131         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3132                 #
3133                 # as it was called, minus the query string.
3134                 #
3135                 # Some sites use Apache rewrite rules to handle subdomains,
3136                 # and have PHP set up in a weird way that causes PHP_SELF
3137                 # to contain the rewritten URL instead of the one that the
3138                 # outside world sees.
3139                 #
3140                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3141                 # provides containing the "before" URL.
3142                 return $_SERVER['SCRIPT_NAME'];
3143         } else {
3144                 return $_SERVER['URL'];
3145         }
3146 }
3147
3148 /**
3149  * Convenience function converts boolean values into "true"
3150  * or "false" (string) values
3151  *
3152  * @param $value Boolean
3153  * @return String
3154  */
3155 function wfBoolToStr( $value ) {
3156         return $value ? 'true' : 'false';
3157 }
3158
3159 /**
3160  * Load an extension messages file
3161  * @deprecated in 1.16 (warnings in 1.18, removed in ?)
3162  */
3163 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
3164 }
3165
3166 /**
3167  * Get a platform-independent path to the null file, e.g.
3168  * /dev/null
3169  *
3170  * @return string
3171  */
3172 function wfGetNull() {
3173         return wfIsWindows()
3174                 ? 'NUL'
3175                 : '/dev/null';
3176 }
3177
3178 /**
3179  * Displays a maxlag error
3180  *
3181  * @param $host String: server that lags the most
3182  * @param $lag Integer: maxlag (actual)
3183  * @param $maxLag Integer: maxlag (requested)
3184  */
3185 function wfMaxlagError( $host, $lag, $maxLag ) {
3186         global $wgShowHostnames;
3187         header( 'HTTP/1.1 503 Service Unavailable' );
3188         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
3189         header( 'X-Database-Lag: ' . intval( $lag ) );
3190         header( 'Content-Type: text/plain' );
3191         if( $wgShowHostnames ) {
3192                 echo "Waiting for $host: $lag seconds lagged\n";
3193         } else {
3194                 echo "Waiting for a database server: $lag seconds lagged\n";
3195         }
3196 }
3197
3198 /**
3199  * Throws a warning that $function is deprecated
3200  * @param $function String
3201  * @return null
3202  */
3203 function wfDeprecated( $function ) {
3204         static $functionsWarned = array();
3205         if ( !isset( $functionsWarned[$function] ) ) {
3206                 $functionsWarned[$function] = true;
3207                 wfWarn( "Use of $function is deprecated.", 2 );
3208         }
3209 }
3210
3211 /**
3212  * Send a warning either to the debug log or in a PHP error depending on
3213  * $wgDevelopmentWarnings
3214  *
3215  * @param $msg String: message to send
3216  * @param $callerOffset Integer: number of itmes to go back in the backtrace to
3217  *        find the correct caller (1 = function calling wfWarn, ...)
3218  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3219  *        is true
3220  */
3221 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3222         $callers = wfDebugBacktrace();
3223         if( isset( $callers[$callerOffset + 1] ) ){
3224                 $callerfunc = $callers[$callerOffset + 1];
3225                 $callerfile = $callers[$callerOffset];
3226                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3227                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3228                 } else {
3229                         $file = '(internal function)';
3230                 }
3231                 $func = '';
3232                 if( isset( $callerfunc['class'] ) ) {
3233                         $func .= $callerfunc['class'] . '::';
3234                 }
3235                 $func .= @$callerfunc['function'];
3236                 $msg .= " [Called from $func in $file]";
3237         }
3238
3239         global $wgDevelopmentWarnings;
3240         if ( $wgDevelopmentWarnings ) {
3241                 trigger_error( $msg, $level );
3242         } else {
3243                 wfDebug( "$msg\n" );
3244         }
3245 }
3246
3247 /**
3248  * Sleep until the worst slave's replication lag is less than or equal to
3249  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
3250  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3251  * a no-op if there are no slaves.
3252  *
3253  * Every time the function has to wait for a slave, it will print a message to
3254  * that effect (and then sleep for a little while), so it's probably not best
3255  * to use this outside maintenance scripts in its present form.
3256  *
3257  * @param $maxLag Integer
3258  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3259  * @return null
3260  */
3261 function wfWaitForSlaves( $maxLag, $wiki = false ) {
3262         if( $maxLag ) {
3263                 $lb = wfGetLB( $wiki );
3264                 list( $host, $lag ) = $lb->getMaxLag( $wiki );
3265                 while( $lag > $maxLag ) {
3266                         $name = @gethostbyaddr( $host );
3267                         if( $name !== false ) {
3268                                 $host = $name;
3269                         }
3270                         print "Waiting for $host (lagged $lag seconds)...\n";
3271                         sleep( $maxLag );
3272                         list( $host, $lag ) = $lb->getMaxLag();
3273                 }
3274         }
3275 }
3276
3277 /**
3278  * Output some plain text in command-line mode or in the installer (updaters.inc).
3279  * Do not use it in any other context, its behaviour is subject to change.
3280  */
3281 function wfOut( $s ) {
3282         global $wgCommandLineMode;
3283         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3284                 echo $s;
3285         } else {
3286                 echo htmlspecialchars( $s );
3287         }
3288         flush();
3289 }
3290
3291 /**
3292  * Count down from $n to zero on the terminal, with a one-second pause
3293  * between showing each number. For use in command-line scripts.
3294  */
3295 function wfCountDown( $n ) {
3296         for ( $i = $n; $i >= 0; $i-- ) {
3297                 if ( $i != $n ) {
3298                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3299                 }
3300                 echo $i;
3301                 flush();
3302                 if ( $i ) {
3303                         sleep( 1 );
3304                 }
3305         }
3306         echo "\n";
3307 }
3308
3309 /**
3310  * Generate a random 32-character hexadecimal token.
3311  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3312  *              characters before hashing.
3313  */
3314 function wfGenerateToken( $salt = '' ) {
3315         $salt = serialize( $salt );
3316
3317         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3318 }
3319
3320 /**
3321  * Replace all invalid characters with -
3322  * @param $name Mixed: filename to process
3323  */
3324 function wfStripIllegalFilenameChars( $name ) {
3325         global $wgIllegalFileChars;
3326         $name = wfBaseName( $name );
3327         $name = preg_replace(
3328                 "/[^" . Title::legalChars() . "]" .
3329                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3330                         "/",
3331                 '-',
3332                 $name
3333         );
3334         return $name;
3335 }
3336
3337 /**
3338  * Insert array into another array after the specified *KEY*
3339  * @param $array Array: The array.
3340  * @param $insert Array: The array to insert.
3341  * @param $after Mixed: The key to insert after
3342  */
3343 function wfArrayInsertAfter( $array, $insert, $after ) {
3344         // Find the offset of the element to insert after.
3345         $keys = array_keys( $array );
3346         $offsetByKey = array_flip( $keys );
3347
3348         $offset = $offsetByKey[$after];
3349
3350         // Insert at the specified offset
3351         $before = array_slice( $array, 0, $offset + 1, true );
3352         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
3353
3354         $output = $before + $insert + $after;
3355
3356         return $output;
3357 }
3358
3359 /* Recursively converts the parameter (an object) to an array with the same data */
3360 function wfObjectToArray( $object, $recursive = true ) {
3361         $array = array();
3362         foreach ( get_object_vars( $object ) as $key => $value ) {
3363                 if ( is_object( $value ) && $recursive ) {
3364                         $value = wfObjectToArray( $value );
3365                 }
3366
3367                 $array[$key] = $value;
3368         }
3369
3370         return $array;
3371 }
3372
3373 /**
3374  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3375  * @return Integer value memory was set to.
3376  */
3377 function wfMemoryLimit() {
3378         global $wgMemoryLimit;
3379         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3380         $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3381         if( $memlimit != -1 ) {
3382                 if( $conflimit == -1 ) {
3383                         wfDebug( "Removing PHP's memory limit\n" );
3384                         wfSuppressWarnings();
3385                         ini_set( 'memory_limit', $conflimit );
3386                         wfRestoreWarnings();
3387                         return $conflimit;
3388                 } elseif ( $conflimit > $memlimit ) {
3389                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3390                         wfSuppressWarnings();
3391                         ini_set( 'memory_limit', $conflimit );
3392                         wfRestoreWarnings();
3393                         return $conflimit;
3394                 }
3395         }
3396         return $memlimit;
3397 }
3398
3399 /**
3400  * Converts shorthand byte notation to integer form
3401  * @param $string String
3402  * @return Integer
3403  */
3404 function wfShorthandToInteger( $string = '' ) {
3405         $string = trim( $string );
3406         if( empty( $string ) ) {
3407                 return -1;
3408         }
3409         $last = strtolower( $string[strlen( $string ) - 1] );
3410         $val = intval( $string );
3411         switch( $last ) {
3412                 case 'g':
3413                         $val *= 1024;
3414                 case 'm':
3415                         $val *= 1024;
3416                 case 'k':
3417                         $val *= 1024;
3418         }
3419
3420         return $val;
3421 }
3422
3423 /**
3424  * Get the normalised IETF language tag
3425  * @param $code String: The language code.
3426  * @return $langCode String: The language code which complying with BCP 47 standards.
3427  */
3428 function wfBCP47( $code ) {
3429         $codeSegment = explode( '-', $code );
3430         foreach ( $codeSegment as $segNo => $seg ) {
3431                 if ( count( $codeSegment ) > 0 ) {
3432                         // ISO 3166 country code
3433                         if ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3434                                 $codeBCP[$segNo] = strtoupper( $seg );
3435                         // ISO 15924 script code
3436                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3437                                 $codeBCP[$segNo] = ucfirst( $seg );
3438                         // Use lowercase for other cases
3439                         } else {
3440                                 $codeBCP[$segNo] = strtolower( $seg );
3441                         }
3442                 } else {
3443                 // Use lowercase for single segment
3444                         $codeBCP[$segNo] = strtolower( $seg );
3445                 }
3446         }
3447         $langCode = implode( '-', $codeBCP );
3448         return $langCode;
3449 }
3450
3451 function wfArrayMap( $function, $input ) {
3452         $ret = array_map( $function, $input );
3453         foreach ( $ret as $key => $value ) {
3454                 $taint = istainted( $input[$key] );
3455                 if ( $taint ) {
3456                         taint( $ret[$key], $taint );
3457                 }
3458         }
3459         return $ret;
3460 }
3461
3462 /**
3463  * Returns the PackageRepository object for interaction with the package repository.
3464  *
3465  * TODO: Make the repository type also configurable.
3466  *
3467  * @since 1.17
3468  *
3469  * @return PackageRepository
3470  */
3471 function wfGetRepository() {
3472         global $wgRepositoryApiLocation;
3473         static $repository = false;
3474
3475         if ( $repository === false ) {
3476                 $repository = new DistributionRepository( $wgRepositoryApiLocation );
3477         }
3478
3479         return $repository;
3480 }