includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 require_once dirname( __FILE__ ) . '/normal/UtfNormalUtil.php';
  12
  13 // Hide compatibility functions from Doxygen
  14 /// @cond
  15
  16 /**
  17  * Compatibility functions
  18  *
  19  * We support PHP 5.1.x and up.
  20  * Re-implementations of newer functions or functions in non-standard
  21  * PHP extensions may be included here.
  22  */
  23 if( !function_exists( 'iconv' ) ) {
  24         # iconv support is not in the default configuration and so may not be present.
  25         # Assume will only ever use utf-8 and iso-8859-1.
  26         # This will *not* work in all circumstances.
  27         function iconv( $from, $to, $string ) {
  28                 if ( substr( $to, -8 ) == '//IGNORE' ) {
  29                         $to = substr( $to, 0, strlen( $to ) - 8 );
  30                 }
  31                 if( strcasecmp( $from, $to ) == 0 ) {
  32                         return $string;
  33                 }
  34                 if( strcasecmp( $from, 'utf-8' ) == 0 ) {
  35                         return utf8_decode( $string );
  36                 }
  37                 if( strcasecmp( $to, 'utf-8' ) == 0 ) {
  38                         return utf8_encode( $string );
  39                 }
  40                 return $string;
  41         }
  42 }
  43
  44 if ( !function_exists( 'mb_substr' ) ) {
  45         /**
  46          * Fallback implementation for mb_substr, hardcoded to UTF-8.
  47          * Attempts to be at least _moderately_ efficient; best optimized
  48          * for relatively small offset and count values -- about 5x slower
  49          * than native mb_string in my testing.
  50          *
  51          * Larger offsets are still fairly efficient for Latin text, but
  52          * can be up to 100x slower than native if the text is heavily
  53          * multibyte and we have to slog through a few hundred kb.
  54          */
  55         function mb_substr( $str, $start, $count='end' ) {
  56                 if( $start != 0 ) {
  57                         $split = mb_substr_split_unicode( $str, intval( $start ) );
  58                         $str = substr( $str, $split );
  59                 }
  60
  61                 if( $count !== 'end' ) {
  62                         $split = mb_substr_split_unicode( $str, intval( $count ) );
  63                         $str = substr( $str, 0, $split );
  64                 }
  65
  66                 return $str;
  67         }
  68
  69         function mb_substr_split_unicode( $str, $splitPos ) {
  70                 if( $splitPos == 0 ) {
  71                         return 0;
  72                 }
  73
  74                 $byteLen = strlen( $str );
  75
  76                 if( $splitPos > 0 ) {
  77                         if( $splitPos > 256 ) {
  78                                 // Optimize large string offsets by skipping ahead N bytes.
  79                                 // This will cut out most of our slow time on Latin-based text,
  80                                 // and 1/2 to 1/3 on East European and Asian scripts.
  81                                 $bytePos = $splitPos;
  82                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  83                                         ++$bytePos;
  84                                 }
  85                                 $charPos = mb_strlen( substr( $str, 0, $bytePos ) );
  86                         } else {
  87                                 $charPos = 0;
  88                                 $bytePos = 0;
  89                         }
  90
  91                         while( $charPos++ < $splitPos ) {
  92                                 ++$bytePos;
  93                                 // Move past any tail bytes
  94                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  95                                         ++$bytePos;
  96                                 }
  97                         }
  98                 } else {
  99                         $splitPosX = $splitPos + 1;
 100                         $charPos = 0; // relative to end of string; we don't care about the actual char position here
 101                         $bytePos = $byteLen;
 102                         while( $bytePos > 0 && $charPos-- >= $splitPosX ) {
 103                                 --$bytePos;
 104                                 // Move past any tail bytes
 105                                 while ( $bytePos > 0 && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
 106                                         --$bytePos;
 107                                 }
 108                         }
 109                 }
 110
 111                 return $bytePos;
 112         }
 113 }
 114
 115 if ( !function_exists( 'mb_strlen' ) ) {
 116         /**
 117          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
 118          * @param string $str
 119          * @param string $enc optional encoding; ignored
 120          * @return int
 121          */
 122         function mb_strlen( $str, $enc = '' ) {
 123                 $counts = count_chars( $str );
 124                 $total = 0;
 125
 126                 // Count ASCII bytes
 127                 for( $i = 0; $i < 0x80; $i++ ) {
 128                         $total += $counts[$i];
 129                 }
 130
 131                 // Count multibyte sequence heads
 132                 for( $i = 0xc0; $i < 0xff; $i++ ) {
 133                         $total += $counts[$i];
 134                 }
 135                 return $total;
 136         }
 137 }
 138
 139
 140 if( !function_exists( 'mb_strpos' ) ) {
 141         /**
 142          * Fallback implementation of mb_strpos, hardcoded to UTF-8.
 143          * @param $haystack String
 144          * @param $needle String
 145          * @param $offset String: optional start position
 146          * @param $encoding String: optional encoding; ignored
 147          * @return int
 148          */
 149         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 150                 $needle = preg_quote( $needle, '/' );
 151
 152                 $ar = array();
 153                 preg_match( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 154
 155                 if( isset( $ar[0][1] ) ) {
 156                         return $ar[0][1];
 157                 } else {
 158                         return false;
 159                 }
 160         }
 161 }
 162
 163 if( !function_exists( 'mb_strrpos' ) ) {
 164         /**
 165          * Fallback implementation of mb_strrpos, hardcoded to UTF-8.
 166          * @param $haystack String
 167          * @param $needle String
 168          * @param $offset String: optional start position
 169          * @param $encoding String: optional encoding; ignored
 170          * @return int
 171          */
 172         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 173                 $needle = preg_quote( $needle, '/' );
 174
 175                 $ar = array();
 176                 preg_match_all( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 177
 178                 if( isset( $ar[0] ) && count( $ar[0] ) > 0 &&
 179                         isset( $ar[0][count( $ar[0] ) - 1][1] ) ) {
 180                         return $ar[0][count( $ar[0] ) - 1][1];
 181                 } else {
 182                         return false;
 183                 }
 184         }
 185 }
 186
 187 // Support for Wietse Venema's taint feature
 188 if ( !function_exists( 'istainted' ) ) {
 189         function istainted( $var ) {
 190                 return 0;
 191         }
 192         function taint( $var, $level = 0 ) {}
 193         function untaint( $var, $level = 0 ) {}
 194         define( 'TC_HTML', 1 );
 195         define( 'TC_SHELL', 1 );
 196         define( 'TC_MYSQL', 1 );
 197         define( 'TC_PCRE', 1 );
 198         define( 'TC_SELF', 1 );
 199 }
 200 /// @endcond
 201
 202
 203 /**
 204  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 205  */
 206 function wfArrayDiff2( $a, $b ) {
 207         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 208 }
 209 function wfArrayDiff2_cmp( $a, $b ) {
 210         if ( !is_array( $a ) ) {
 211                 return strcmp( $a, $b );
 212         } elseif ( count( $a ) !== count( $b ) ) {
 213                 return count( $a ) < count( $b ) ? -1 : 1;
 214         } else {
 215                 reset( $a );
 216                 reset( $b );
 217                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 218                         $cmp = strcmp( $valueA, $valueB );
 219                         if ( $cmp !== 0 ) {
 220                                 return $cmp;
 221                         }
 222                 }
 223                 return 0;
 224         }
 225 }
 226
 227 /**
 228  * Get a random decimal value between 0 and 1, in a way
 229  * not likely to give duplicate values for any realistic
 230  * number of articles.
 231  *
 232  * @return string
 233  */
 234 function wfRandom() {
 235         # The maximum random value is "only" 2^31-1, so get two random
 236         # values to reduce the chance of dupes
 237         $max = mt_getrandmax() + 1;
 238         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 239                 / $max / $max, 12, '.', '' );
 240         return $rand;
 241 }
 242
 243 /**
 244  * We want some things to be included as literal characters in our title URLs
 245  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 246  * all of the following should be safe:
 247  *
 248  * ;:@&=$-_.+!*'(),
 249  *
 250  * But + is not safe because it's used to indicate a space; &= are only safe in
 251  * paths and not in queries (and we don't distinguish here); ' seems kind of
 252  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 253  * is reserved, we don't care.  So the list we unescape is:
 254  *
 255  * ;:@$!*(),/
 256  *
 257  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 258  * so no fancy : for IIS7.
 259  *
 260  * %2F in the page titles seems to fatally break for some reason.
 261  *
 262  * @param $s String:
 263  * @return string
 264 */
 265 function wfUrlencode( $s ) {
 266         static $needle;
 267         if ( is_null( $needle ) ) {
 268                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 269                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 270                         $needle[] = '%3A';
 271                 }
 272         }
 273
 274         $s = urlencode( $s );
 275         $s = str_ireplace(
 276                 $needle,
 277                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 278                 $s
 279         );
 280
 281         return $s;
 282 }
 283
 284 /**
 285  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 286  * In normal operation this is a NOP.
 287  *
 288  * Controlling globals:
 289  * $wgDebugLogFile - points to the log file
 290  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 291  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 292  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 293  *
 294  * @param $text String
 295  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 296  */
 297 function wfDebug( $text, $logonly = false ) {
 298         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 299         global $wgDebugLogPrefix, $wgShowDebug;
 300
 301         static $cache = array(); // Cache of unoutputted messages
 302         $text = wfDebugTimer() . $text;
 303
 304         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 305         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 306                 return;
 307         }
 308
 309         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 310                 $cache[] = $text;
 311
 312                 if ( isset( $wgOut ) && StubObject::isRealObject( $wgOut ) ) {
 313                         // add the message and any cached messages to the output
 314                         array_map( array( $wgOut, 'debug' ), $cache );
 315                         $cache = array();
 316                 }
 317         }
 318         if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 319                 # Strip unprintables; they can switch terminal modes when binary data
 320                 # gets dumped, which is pretty annoying.
 321                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 322                 $text = $wgDebugLogPrefix . $text;
 323                 wfErrorLog( $text, $wgDebugLogFile );
 324         }
 325 }
 326
 327 function wfDebugTimer() {
 328         global $wgDebugTimestamps;
 329         if ( !$wgDebugTimestamps ) {
 330                 return '';
 331         }
 332         static $start = null;
 333
 334         if ( $start === null ) {
 335                 $start = microtime( true );
 336                 $prefix = "\n$start";
 337         } else {
 338                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 339         }
 340
 341         return $prefix . '  ';
 342 }
 343
 344 /**
 345  * Send a line giving PHP memory usage.
 346  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 347  */
 348 function wfDebugMem( $exact = false ) {
 349         $mem = memory_get_usage();
 350         if( !$exact ) {
 351                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 352         } else {
 353                 $mem .= ' bytes';
 354         }
 355         wfDebug( "Memory usage: $mem\n" );
 356 }
 357
 358 /**
 359  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 360  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 361  *
 362  * @param $logGroup String
 363  * @param $text String
 364  * @param $public Bool: whether to log the event in the public log if no private
 365  *                     log file is specified, (default true)
 366  */
 367 function wfDebugLog( $logGroup, $text, $public = true ) {
 368         global $wgDebugLogGroups, $wgShowHostnames;
 369         $text = trim( $text ) . "\n";
 370         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 371                 $time = wfTimestamp( TS_DB );
 372                 $wiki = wfWikiID();
 373                 if ( $wgShowHostnames ) {
 374                         $host = wfHostname();
 375                 } else {
 376                         $host = '';
 377                 }
 378                 wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 379         } elseif ( $public === true ) {
 380                 wfDebug( $text, true );
 381         }
 382 }
 383
 384 /**
 385  * Log for database errors
 386  * @param $text String: database error message.
 387  */
 388 function wfLogDBError( $text ) {
 389         global $wgDBerrorLog, $wgDBname;
 390         if ( $wgDBerrorLog ) {
 391                 $host = trim(`hostname`);
 392                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 393                 wfErrorLog( $text, $wgDBerrorLog );
 394         }
 395 }
 396
 397 /**
 398  * Log to a file without getting "file size exceeded" signals.
 399  *
 400  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 401  * send lines to the specified port, prefixed by the specified prefix and a space.
 402  */
 403 function wfErrorLog( $text, $file ) {
 404         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 405                 # Needs the sockets extension
 406                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 407                         // IPv6 bracketed host
 408                         $host = $m[2];
 409                         $port = intval( $m[3] );
 410                         $prefix = isset( $m[4] ) ? $m[4] : false;
 411                         $domain = AF_INET6;
 412                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 413                         $host = $m[2];
 414                         if ( !IP::isIPv4( $host ) ) {
 415                                 $host = gethostbyname( $host );
 416                         }
 417                         $port = intval( $m[3] );
 418                         $prefix = isset( $m[4] ) ? $m[4] : false;
 419                         $domain = AF_INET;
 420                 } else {
 421                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 422                 }
 423                 // Clean it up for the multiplexer
 424                 if ( strval( $prefix ) !== '' ) {
 425                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 426                         if ( substr( $text, -1 ) != "\n" ) {
 427                                 $text .= "\n";
 428                         }
 429                 }
 430
 431                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 432                 if ( !$sock ) {
 433                         return;
 434                 }
 435                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 436                 socket_close( $sock );
 437         } else {
 438                 wfSuppressWarnings();
 439                 $exists = file_exists( $file );
 440                 $size = $exists ? filesize( $file ) : false;
 441                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 442                         error_log( $text, 3, $file );
 443                 }
 444                 wfRestoreWarnings();
 445         }
 446 }
 447
 448 /**
 449  * @todo document
 450  */
 451 function wfLogProfilingData() {
 452         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 453         global $wgProfiler, $wgProfileLimit, $wgUser;
 454         # Profiling must actually be enabled...
 455         if( is_null( $wgProfiler ) ) {
 456                 return;
 457         }
 458         # Get total page request time
 459         $now = wfTime();
 460         $elapsed = $now - $wgRequestTime;
 461         # Only show pages that longer than $wgProfileLimit time (default is 0)
 462         if( $elapsed <= $wgProfileLimit ) {
 463                 return;
 464         }
 465         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 466         $forward = '';
 467         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 468                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 469         }
 470         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 471                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 472         }
 473         if( !empty( $_SERVER['HTTP_FROM'] ) ) {
 474                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 475         }
 476         if( $forward ) {
 477                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 478         }
 479         // Don't unstub $wgUser at this late stage just for statistics purposes
 480         // FIXME: We can detect some anons even if it is not loaded. See User::getId()
 481         if( $wgUser->mDataLoaded && $wgUser->isAnon() ) {
 482                 $forward .= ' anon';
 483         }
 484         $log = sprintf( "%s\t%04.3f\t%s\n",
 485                 gmdate( 'YmdHis' ), $elapsed,
 486                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 487         if ( $wgDebugLogFile != '' && ( $wgRequest->getVal( 'action' ) != 'raw' || $wgDebugRawPage ) ) {
 488                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 489         }
 490 }
 491
 492 /**
 493  * Check if the wiki read-only lock file is present. This can be used to lock
 494  * off editing functions, but doesn't guarantee that the database will not be
 495  * modified.
 496  * @return bool
 497  */
 498 function wfReadOnly() {
 499         global $wgReadOnlyFile, $wgReadOnly;
 500
 501         if ( !is_null( $wgReadOnly ) ) {
 502                 return (bool)$wgReadOnly;
 503         }
 504         if ( $wgReadOnlyFile == '' ) {
 505                 return false;
 506         }
 507         // Set $wgReadOnly for faster access next time
 508         if ( is_file( $wgReadOnlyFile ) ) {
 509                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 510         } else {
 511                 $wgReadOnly = false;
 512         }
 513         return (bool)$wgReadOnly;
 514 }
 515
 516 function wfReadOnlyReason() {
 517         global $wgReadOnly;
 518         wfReadOnly();
 519         return $wgReadOnly;
 520 }
 521
 522 /**
 523  * Return a Language object from $langcode
 524  * @param $langcode Mixed: either:
 525  *                  - a Language object
 526  *                  - code of the language to get the message for, if it is
 527  *                    a valid code create a language for that language, if
 528  *                    it is a string but not a valid code then make a basic
 529  *                    language object
 530  *                  - a boolean: if it's false then use the current users
 531  *                    language (as a fallback for the old parameter
 532  *                    functionality), or if it is true then use the wikis
 533  * @return Language object
 534  */
 535 function wfGetLangObj( $langcode = false ) {
 536         # Identify which language to get or create a language object for.
 537         # Using is_object here due to Stub objects.
 538         if( is_object( $langcode ) ) {
 539                 # Great, we already have the object (hopefully)!
 540                 return $langcode;
 541         }
 542
 543         global $wgContLang, $wgLanguageCode;
 544         if( $langcode === true || $langcode === $wgLanguageCode ) {
 545                 # $langcode is the language code of the wikis content language object.
 546                 # or it is a boolean and value is true
 547                 return $wgContLang;
 548         }
 549
 550         global $wgLang;
 551         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 552                 # $langcode is the language code of user language object.
 553                 # or it was a boolean and value is false
 554                 return $wgLang;
 555         }
 556
 557         $validCodes = array_keys( Language::getLanguageNames() );
 558         if( in_array( $langcode, $validCodes ) ) {
 559                 # $langcode corresponds to a valid language.
 560                 return Language::factory( $langcode );
 561         }
 562
 563         # $langcode is a string, but not a valid language code; use content language.
 564         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 565         return $wgContLang;
 566 }
 567
 568 /**
 569  * Use this instead of $wgContLang, when working with user interface.
 570  * User interface is currently hard coded according to wiki content language
 571  * in many ways, especially regarding to text direction. There is lots stuff
 572  * to fix, hence this function to keep the old behaviour unless the global
 573  * $wgBetterDirectionality is enabled (or removed when everything works).
 574  */
 575 function wfUILang() {
 576         global $wgBetterDirectionality;
 577         return wfGetLangObj( !$wgBetterDirectionality );
 578 }
 579
 580 /**
 581  * This is the new function for getting translated interface messages.
 582  * See the Message class for documentation how to use them.
 583  * The intention is that this function replaces all old wfMsg* functions.
 584  * @param $key \string Message key.
 585  * Varargs: normal message parameters.
 586  * @return \type{Message}
 587  * @since 1.17
 588  */
 589 function wfMessage( $key /*...*/) {
 590         $params = func_get_args();
 591         array_shift( $params );
 592         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 593                 $params = $params[0];
 594         }
 595         return new Message( $key, $params );
 596 }
 597
 598 /**
 599  * This function accepts multiple message keys and returns a message instance
 600  * for the first message which is non-empty. If all messages are empty then an
 601  * instance of the first message key is returned.
 602  * Varargs: message keys
 603  * @return \type{Message}
 604  * @since 1.18
 605  */
 606 function wfMessageFallback( /*...*/ ) {
 607         $keys = func_get_args();
 608         $first = $keys[0];
 609         foreach ( $keys as $key ) {
 610                 if ( wfEmptyMsg( $key ) ) {
 611                         continue;
 612                 }
 613                 return wfMessage( $key );
 614         }
 615         return wfMessage( $first );
 616 }
 617
 618 /**
 619  * Get a message from anywhere, for the current user language.
 620  *
 621  * Use wfMsgForContent() instead if the message should NOT
 622  * change depending on the user preferences.
 623  *
 624  * @param $key String: lookup key for the message, usually
 625  *    defined in languages/Language.php
 626  *
 627  * This function also takes extra optional parameters (not
 628  * shown in the function definition), which can be used to
 629  * insert variable text into the predefined message.
 630  */
 631 function wfMsg( $key ) {
 632         $args = func_get_args();
 633         array_shift( $args );
 634         return wfMsgReal( $key, $args, true );
 635 }
 636
 637 /**
 638  * Same as above except doesn't transform the message
 639  */
 640 function wfMsgNoTrans( $key ) {
 641         $args = func_get_args();
 642         array_shift( $args );
 643         return wfMsgReal( $key, $args, true, false, false );
 644 }
 645
 646 /**
 647  * Get a message from anywhere, for the current global language
 648  * set with $wgLanguageCode.
 649  *
 650  * Use this if the message should NOT change dependent on the
 651  * language set in the user's preferences. This is the case for
 652  * most text written into logs, as well as link targets (such as
 653  * the name of the copyright policy page). Link titles, on the
 654  * other hand, should be shown in the UI language.
 655  *
 656  * Note that MediaWiki allows users to change the user interface
 657  * language in their preferences, but a single installation
 658  * typically only contains content in one language.
 659  *
 660  * Be wary of this distinction: If you use wfMsg() where you should
 661  * use wfMsgForContent(), a user of the software may have to
 662  * customize potentially hundreds of messages in
 663  * order to, e.g., fix a link in every possible language.
 664  *
 665  * @param $key String: lookup key for the message, usually
 666  *    defined in languages/Language.php
 667  */
 668 function wfMsgForContent( $key ) {
 669         global $wgForceUIMsgAsContentMsg;
 670         $args = func_get_args();
 671         array_shift( $args );
 672         $forcontent = true;
 673         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 674                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 675         {
 676                 $forcontent = false;
 677         }
 678         return wfMsgReal( $key, $args, true, $forcontent );
 679 }
 680
 681 /**
 682  * Same as above except doesn't transform the message
 683  */
 684 function wfMsgForContentNoTrans( $key ) {
 685         global $wgForceUIMsgAsContentMsg;
 686         $args = func_get_args();
 687         array_shift( $args );
 688         $forcontent = true;
 689         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 690                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 691         {
 692                 $forcontent = false;
 693         }
 694         return wfMsgReal( $key, $args, true, $forcontent, false );
 695 }
 696
 697 /**
 698  * Get a message from the language file, for the UI elements
 699  */
 700 function wfMsgNoDB( $key ) {
 701         $args = func_get_args();
 702         array_shift( $args );
 703         return wfMsgReal( $key, $args, false );
 704 }
 705
 706 /**
 707  * Get a message from the language file, for the content
 708  */
 709 function wfMsgNoDBForContent( $key ) {
 710         global $wgForceUIMsgAsContentMsg;
 711         $args = func_get_args();
 712         array_shift( $args );
 713         $forcontent = true;
 714         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 715                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 716         {
 717                 $forcontent = false;
 718         }
 719         return wfMsgReal( $key, $args, false, $forcontent );
 720 }
 721
 722
 723 /**
 724  * Really get a message
 725  * @param $key String: key to get.
 726  * @param $args
 727  * @param $useDB Boolean
 728  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 729  * @param $transform Boolean: Whether or not to transform the message.
 730  * @return String: the requested message.
 731  */
 732 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 733         wfProfileIn( __METHOD__ );
 734         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 735         $message = wfMsgReplaceArgs( $message, $args );
 736         wfProfileOut( __METHOD__ );
 737         return $message;
 738 }
 739
 740 /**
 741  * This function provides the message source for messages to be edited which are *not* stored in the database.
 742  * @param $key String:
 743  */
 744 function wfMsgWeirdKey( $key ) {
 745         $source = wfMsgGetKey( $key, false, true, false );
 746         if ( wfEmptyMsg( $key, $source ) ) {
 747                 return '';
 748         } else {
 749                 return $source;
 750         }
 751 }
 752
 753 /**
 754  * Fetch a message string value, but don't replace any keys yet.
 755  * @param $key String
 756  * @param $useDB Bool
 757  * @param $langCode String: Code of the language to get the message for, or
 758  *                  behaves as a content language switch if it is a boolean.
 759  * @param $transform Boolean: whether to parse magic words, etc.
 760  * @return string
 761  */
 762 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 763         global $wgMessageCache;
 764
 765         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 766
 767         if ( !is_object( $wgMessageCache ) ) {
 768                 throw new MWException( 'Trying to get message before message cache is initialised' );
 769         }
 770
 771         $message = $wgMessageCache->get( $key, $useDB, $langCode );
 772         if( $message === false ) {
 773                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 774         } elseif ( $transform ) {
 775                 $message = $wgMessageCache->transform( $message );
 776         }
 777         return $message;
 778 }
 779
 780 /**
 781  * Replace message parameter keys on the given formatted output.
 782  *
 783  * @param $message String
 784  * @param $args Array
 785  * @return string
 786  * @private
 787  */
 788 function wfMsgReplaceArgs( $message, $args ) {
 789         # Fix windows line-endings
 790         # Some messages are split with explode("\n", $msg)
 791         $message = str_replace( "\r", '', $message );
 792
 793         // Replace arguments
 794         if ( count( $args ) ) {
 795                 if ( is_array( $args[0] ) ) {
 796                         $args = array_values( $args[0] );
 797                 }
 798                 $replacementKeys = array();
 799                 foreach( $args as $n => $param ) {
 800                         $replacementKeys['$' . ( $n + 1 )] = $param;
 801                 }
 802                 $message = strtr( $message, $replacementKeys );
 803         }
 804
 805         return $message;
 806 }
 807
 808 /**
 809  * Return an HTML-escaped version of a message.
 810  * Parameter replacements, if any, are done *after* the HTML-escaping,
 811  * so parameters may contain HTML (eg links or form controls). Be sure
 812  * to pre-escape them if you really do want plaintext, or just wrap
 813  * the whole thing in htmlspecialchars().
 814  *
 815  * @param $key String
 816  * @param string ... parameters
 817  * @return string
 818  */
 819 function wfMsgHtml( $key ) {
 820         $args = func_get_args();
 821         array_shift( $args );
 822         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 823 }
 824
 825 /**
 826  * Return an HTML version of message
 827  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 828  * so parameters may contain HTML (eg links or form controls). Be sure
 829  * to pre-escape them if you really do want plaintext, or just wrap
 830  * the whole thing in htmlspecialchars().
 831  *
 832  * @param $key String
 833  * @param string ... parameters
 834  * @return string
 835  */
 836 function wfMsgWikiHtml( $key ) {
 837         global $wgOut;
 838         $args = func_get_args();
 839         array_shift( $args );
 840         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 841 }
 842
 843 /**
 844  * Returns message in the requested format
 845  * @param $key String: key of the message
 846  * @param $options Array: processing rules. Can take the following options:
 847  *   <i>parse</i>: parses wikitext to HTML
 848  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 849  *       p's added by parser or tidy
 850  *   <i>escape</i>: filters message through htmlspecialchars
 851  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 852  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 853  *   <i>parsemag</i>: transform the message using magic phrases
 854  *   <i>content</i>: fetch message for content language instead of interface
 855  * Also can accept a single associative argument, of the form 'language' => 'xx':
 856  *   <i>language</i>: Language object or language code to fetch message for
 857  *       (overriden by <i>content</i>), its behaviour with parse, parseinline
 858  *       and parsemag is undefined.
 859  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 860  */
 861 function wfMsgExt( $key, $options ) {
 862         global $wgOut;
 863
 864         $args = func_get_args();
 865         array_shift( $args );
 866         array_shift( $args );
 867         $options = (array)$options;
 868
 869         foreach( $options as $arrayKey => $option ) {
 870                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 871                         # An unknown index, neither numeric nor "language"
 872                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 873                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 874                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 875                 'replaceafter', 'parsemag', 'content' ) ) ) {
 876                         # A numeric index with unknown value
 877                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 878                 }
 879         }
 880
 881         if( in_array( 'content', $options, true ) ) {
 882                 $forContent = true;
 883                 $langCode = true;
 884         } elseif( array_key_exists( 'language', $options ) ) {
 885                 $forContent = false;
 886                 $langCode = wfGetLangObj( $options['language'] );
 887         } else {
 888                 $forContent = false;
 889                 $langCode = false;
 890         }
 891
 892         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 893
 894         if( !in_array( 'replaceafter', $options, true ) ) {
 895                 $string = wfMsgReplaceArgs( $string, $args );
 896         }
 897
 898         if( in_array( 'parse', $options, true ) ) {
 899                 $string = $wgOut->parse( $string, true, !$forContent );
 900         } elseif ( in_array( 'parseinline', $options, true ) ) {
 901                 $string = $wgOut->parse( $string, true, !$forContent );
 902                 $m = array();
 903                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 904                         $string = $m[1];
 905                 }
 906         } elseif ( in_array( 'parsemag', $options, true ) ) {
 907                 global $wgMessageCache;
 908                 if ( isset( $wgMessageCache ) ) {
 909                         $string = $wgMessageCache->transform( $string,
 910                                 !$forContent,
 911                                 is_object( $langCode ) ? $langCode : null );
 912                 }
 913         }
 914
 915         if ( in_array( 'escape', $options, true ) ) {
 916                 $string = htmlspecialchars ( $string );
 917         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 918                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 919         }
 920
 921         if( in_array( 'replaceafter', $options, true ) ) {
 922                 $string = wfMsgReplaceArgs( $string, $args );
 923         }
 924
 925         return $string;
 926 }
 927
 928
 929 /**
 930  * Just like exit() but makes a note of it.
 931  * Commits open transactions except if the error parameter is set
 932  *
 933  * @deprecated Please return control to the caller or throw an exception. Will
 934  *             be removed in 1.19.
 935  */
 936 function wfAbruptExit( $error = false ) {
 937         static $called = false;
 938         if ( $called ) {
 939                 exit( -1 );
 940         }
 941         $called = true;
 942
 943         wfDeprecated( __FUNCTION__ );
 944         $bt = wfDebugBacktrace();
 945         if( $bt ) {
 946                 for( $i = 0; $i < count( $bt ); $i++ ) {
 947                         $file = isset( $bt[$i]['file'] ) ? $bt[$i]['file'] : 'unknown';
 948                         $line = isset( $bt[$i]['line'] ) ? $bt[$i]['line'] : 'unknown';
 949                         wfDebug( "WARNING: Abrupt exit in $file at line $line\n");
 950                 }
 951         } else {
 952                 wfDebug( "WARNING: Abrupt exit\n" );
 953         }
 954
 955         wfLogProfilingData();
 956
 957         if ( !$error ) {
 958                 wfGetLB()->closeAll();
 959         }
 960         exit( -1 );
 961 }
 962
 963 /**
 964  * @deprecated Please return control the caller or throw an exception. Will
 965  *             be removed in 1.19.
 966  */
 967 function wfErrorExit() {
 968         wfDeprecated( __FUNCTION__ );
 969         wfAbruptExit( true );
 970 }
 971
 972 /**
 973  * Print a simple message and die, returning nonzero to the shell if any.
 974  * Plain die() fails to return nonzero to the shell if you pass a string.
 975  * @param $msg String
 976  */
 977 function wfDie( $msg = '' ) {
 978         echo $msg;
 979         die( 1 );
 980 }
 981
 982 /**
 983  * Throw a debugging exception. This function previously once exited the process,
 984  * but now throws an exception instead, with similar results.
 985  *
 986  * @param $msg String: message shown when dieing.
 987  */
 988 function wfDebugDieBacktrace( $msg = '' ) {
 989         throw new MWException( $msg );
 990 }
 991
 992 /**
 993  * Fetch server name for use in error reporting etc.
 994  * Use real server name if available, so we know which machine
 995  * in a server farm generated the current page.
 996  * @return string
 997  */
 998 function wfHostname() {
 999         static $host;
1000         if ( is_null( $host ) ) {
1001                 if ( function_exists( 'posix_uname' ) ) {
1002                         // This function not present on Windows
1003                         $uname = @posix_uname();
1004                 } else {
1005                         $uname = false;
1006                 }
1007                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1008                         $host = $uname['nodename'];
1009                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1010                         # Windows computer name
1011                         $host = getenv( 'COMPUTERNAME' );
1012                 } else {
1013                         # This may be a virtual server.
1014                         $host = $_SERVER['SERVER_NAME'];
1015                 }
1016         }
1017         return $host;
1018 }
1019
1020 /**
1021  * Returns a HTML comment with the elapsed time since request.
1022  * This method has no side effects.
1023  * @return string
1024  */
1025 function wfReportTime() {
1026         global $wgRequestTime, $wgShowHostnames;
1027
1028         $now = wfTime();
1029         $elapsed = $now - $wgRequestTime;
1030
1031         return $wgShowHostnames
1032                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1033                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1034 }
1035
1036 /**
1037  * Safety wrapper for debug_backtrace().
1038  *
1039  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1040  * murky circumstances, which may be triggered in part by stub objects
1041  * or other fancy talkin'.
1042  *
1043  * Will return an empty array if Zend Optimizer is detected or if
1044  * debug_backtrace is disabled, otherwise the output from
1045  * debug_backtrace() (trimmed).
1046  *
1047  * @return array of backtrace information
1048  */
1049 function wfDebugBacktrace() {
1050         static $disabled = null;
1051
1052         if( extension_loaded( 'Zend Optimizer' ) ) {
1053                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1054                 return array();
1055         }
1056
1057         if ( is_null( $disabled ) ) {
1058                 $disabled = false;
1059                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1060                 $functions = array_map( 'trim', $functions );
1061                 $functions = array_map( 'strtolower', $functions );
1062                 if ( in_array( 'debug_backtrace', $functions ) ) {
1063                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1064                         $disabled = true;
1065                 }
1066         }
1067         if ( $disabled ) {
1068                 return array();
1069         }
1070
1071         return array_slice( debug_backtrace(), 1 );
1072 }
1073
1074 function wfBacktrace() {
1075         global $wgCommandLineMode;
1076
1077         if ( $wgCommandLineMode ) {
1078                 $msg = '';
1079         } else {
1080                 $msg = "<ul>\n";
1081         }
1082         $backtrace = wfDebugBacktrace();
1083         foreach( $backtrace as $call ) {
1084                 if( isset( $call['file'] ) ) {
1085                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1086                         $file = $f[count( $f ) - 1];
1087                 } else {
1088                         $file = '-';
1089                 }
1090                 if( isset( $call['line'] ) ) {
1091                         $line = $call['line'];
1092                 } else {
1093                         $line = '-';
1094                 }
1095                 if ( $wgCommandLineMode ) {
1096                         $msg .= "$file line $line calls ";
1097                 } else {
1098                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1099                 }
1100                 if( !empty( $call['class'] ) ) {
1101                         $msg .= $call['class'] . '::';
1102                 }
1103                 $msg .= $call['function'] . '()';
1104
1105                 if ( $wgCommandLineMode ) {
1106                         $msg .= "\n";
1107                 } else {
1108                         $msg .= "</li>\n";
1109                 }
1110         }
1111         if ( $wgCommandLineMode ) {
1112                 $msg .= "\n";
1113         } else {
1114                 $msg .= "</ul>\n";
1115         }
1116
1117         return $msg;
1118 }
1119
1120
1121 /* Some generic result counters, pulled out of SearchEngine */
1122
1123
1124 /**
1125  * @todo document
1126  */
1127 function wfShowingResults( $offset, $limit ) {
1128         global $wgLang;
1129         return wfMsgExt(
1130                 'showingresults',
1131                 array( 'parseinline' ),
1132                 $wgLang->formatNum( $limit ),
1133                 $wgLang->formatNum( $offset + 1 )
1134         );
1135 }
1136
1137 /**
1138  * @todo document
1139  */
1140 function wfShowingResultsNum( $offset, $limit, $num ) {
1141         global $wgLang;
1142         return wfMsgExt(
1143                 'showingresultsnum',
1144                 array( 'parseinline' ),
1145                 $wgLang->formatNum( $limit ),
1146                 $wgLang->formatNum( $offset + 1 ),
1147                 $wgLang->formatNum( $num )
1148         );
1149 }
1150
1151 /**
1152  * Generate (prev x| next x) (20|50|100...) type links for paging
1153  * @param $offset String
1154  * @param $limit Integer
1155  * @param $link String
1156  * @param $query String: optional URL query parameter string
1157  * @param $atend Bool: optional param for specified if this is the last page
1158  */
1159 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1160         global $wgLang;
1161         $fmtLimit = $wgLang->formatNum( $limit );
1162         // FIXME: Why on earth this needs one message for the text and another one for tooltip??
1163         # Get prev/next link display text
1164         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1165         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1166         # Get prev/next link title text
1167         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1168         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1169         # Fetch the title object
1170         if( is_object( $link ) ) {
1171                 $title =& $link;
1172         } else {
1173                 $title = Title::newFromText( $link );
1174                 if( is_null( $title ) ) {
1175                         return false;
1176                 }
1177         }
1178         # Make 'previous' link
1179         if( 0 != $offset ) {
1180                 $po = $offset - $limit;
1181                 $po = max( $po, 0 );
1182                 $q = "limit={$limit}&offset={$po}";
1183                 if( $query != '' ) {
1184                         $q .= '&' . $query;
1185                 }
1186                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1187         } else {
1188                 $plink = $prev;
1189         }
1190         # Make 'next' link
1191         $no = $offset + $limit;
1192         $q = "limit={$limit}&offset={$no}";
1193         if( $query != '' ) {
1194                 $q .= '&' . $query;
1195         }
1196         if( $atend ) {
1197                 $nlink = $next;
1198         } else {
1199                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1200         }
1201         # Make links to set number of items per page
1202         $nums = $wgLang->pipeList( array(
1203                 wfNumLink( $offset, 20, $title, $query ),
1204                 wfNumLink( $offset, 50, $title, $query ),
1205                 wfNumLink( $offset, 100, $title, $query ),
1206                 wfNumLink( $offset, 250, $title, $query ),
1207                 wfNumLink( $offset, 500, $title, $query )
1208         ) );
1209         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1210 }
1211
1212 /**
1213  * Generate links for (20|50|100...) items-per-page links
1214  * @param $offset String
1215  * @param $limit Integer
1216  * @param $title Title
1217  * @param $query String: optional URL query parameter string
1218  */
1219 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1220         global $wgLang;
1221         if( $query == '' ) {
1222                 $q = '';
1223         } else {
1224                 $q = $query.'&';
1225         }
1226         $q .= "limit={$limit}&offset={$offset}";
1227         $fmtLimit = $wgLang->formatNum( $limit );
1228         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1229         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1230         return $s;
1231 }
1232
1233 /**
1234  * @todo document
1235  * @todo FIXME: we may want to blacklist some broken browsers
1236  *
1237  * @return bool Whereas client accept gzip compression
1238  */
1239 function wfClientAcceptsGzip() {
1240         static $result = null;
1241         if ( $result === null ) {
1242                 $result = false;
1243                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1244                         # FIXME: we may want to blacklist some broken browsers
1245                         $m = array();
1246                         if( preg_match(
1247                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1248                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1249                                 $m )
1250                         )
1251                         {
1252                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1253                                         $result = false;
1254                                         return $result;
1255                                 }
1256                                 wfDebug( " accepts gzip\n" );
1257                                 $result = true;
1258                         }
1259                 }
1260         }
1261         return $result;
1262 }
1263
1264 /**
1265  * Obtain the offset and limit values from the request string;
1266  * used in special pages
1267  *
1268  * @param $deflimit Default limit if none supplied
1269  * @param $optionname Name of a user preference to check against
1270  * @return array
1271  *
1272  */
1273 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1274         global $wgRequest;
1275         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1276 }
1277
1278 /**
1279  * Escapes the given text so that it may be output using addWikiText()
1280  * without any linking, formatting, etc. making its way through. This
1281  * is achieved by substituting certain characters with HTML entities.
1282  * As required by the callers, <nowiki> is not used. It currently does
1283  * not filter out characters which have special meaning only at the
1284  * start of a line, such as "*".
1285  *
1286  * @param $text String: text to be escaped
1287  */
1288 function wfEscapeWikiText( $text ) {
1289         $text = str_replace(
1290                 array( '[',     '|',      ']',     '\'',    'ISBN ',
1291                         'RFC ',     '://',     "\n=",     '{{',           '}}' ),
1292                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;',
1293                         'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;', '&#125;&#125;' ),
1294                 htmlspecialchars( $text )
1295         );
1296         return $text;
1297 }
1298
1299 /**
1300  * @todo document
1301  * @return float
1302  */
1303 function wfTime() {
1304         return microtime( true );
1305 }
1306
1307 /**
1308  * Sets dest to source and returns the original value of dest
1309  * If source is NULL, it just returns the value, it doesn't set the variable
1310  * If force is true, it will set the value even if source is NULL
1311  */
1312 function wfSetVar( &$dest, $source, $force = false ) {
1313         $temp = $dest;
1314         if ( !is_null( $source ) || $force ) {
1315                 $dest = $source;
1316         }
1317         return $temp;
1318 }
1319
1320 /**
1321  * As for wfSetVar except setting a bit
1322  */
1323 function wfSetBit( &$dest, $bit, $state = true ) {
1324         $temp = (bool)( $dest & $bit );
1325         if ( !is_null( $state ) ) {
1326                 if ( $state ) {
1327                         $dest |= $bit;
1328                 } else {
1329                         $dest &= ~$bit;
1330                 }
1331         }
1332         return $temp;
1333 }
1334
1335 /**
1336  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1337  * "days=7&limit=100". Options in the first array override options in the second.
1338  * Options set to "" will not be output.
1339  */
1340 function wfArrayToCGI( $array1, $array2 = null ) {
1341         if ( !is_null( $array2 ) ) {
1342                 $array1 = $array1 + $array2;
1343         }
1344
1345         $cgi = '';
1346         foreach ( $array1 as $key => $value ) {
1347                 if ( $value !== '' ) {
1348                         if ( $cgi != '' ) {
1349                                 $cgi .= '&';
1350                         }
1351                         if ( is_array( $value ) ) {
1352                                 $firstTime = true;
1353                                 foreach ( $value as $v ) {
1354                                         $cgi .= ( $firstTime ? '' : '&') .
1355                                                 urlencode( $key . '[]' ) . '=' .
1356                                                 urlencode( $v );
1357                                         $firstTime = false;
1358                                 }
1359                         } else {
1360                                 if ( is_object( $value ) ) {
1361                                         $value = $value->__toString();
1362                                 }
1363                                 $cgi .= urlencode( $key ) . '=' .
1364                                         urlencode( $value );
1365                         }
1366                 }
1367         }
1368         return $cgi;
1369 }
1370
1371 /**
1372  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1373  * its argument and returns the same string in array form.  This allows compa-
1374  * tibility with legacy functions that accept raw query strings instead of nice
1375  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1376  * valid query strings, or it will explode.
1377  *
1378  * @param $query String: query string
1379  * @return array Array version of input
1380  */
1381 function wfCgiToArray( $query ) {
1382         if( isset( $query[0] ) && $query[0] == '?' ) {
1383                 $query = substr( $query, 1 );
1384         }
1385         $bits = explode( '&', $query );
1386         $ret = array();
1387         foreach( $bits as $bit ) {
1388                 if( $bit === '' ) {
1389                         continue;
1390                 }
1391                 list( $key, $value ) = explode( '=', $bit );
1392                 $key = urldecode( $key );
1393                 $value = urldecode( $value );
1394                 $ret[$key] = $value;
1395         }
1396         return $ret;
1397 }
1398
1399 /**
1400  * Append a query string to an existing URL, which may or may not already
1401  * have query string parameters already. If so, they will be combined.
1402  *
1403  * @param $url String
1404  * @param $query Mixed: string or associative array
1405  * @return string
1406  */
1407 function wfAppendQuery( $url, $query ) {
1408         if ( is_array( $query ) ) {
1409                 $query = wfArrayToCGI( $query );
1410         }
1411         if( $query != '' ) {
1412                 if( false === strpos( $url, '?' ) ) {
1413                         $url .= '?';
1414                 } else {
1415                         $url .= '&';
1416                 }
1417                 $url .= $query;
1418         }
1419         return $url;
1420 }
1421
1422 /**
1423  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1424  * and $wgProto are correct.
1425  *
1426  * @todo this won't work with current-path-relative URLs
1427  * like "subdir/foo.html", etc.
1428  *
1429  * @param $url String: either fully-qualified or a local path + query
1430  * @return string Fully-qualified URL
1431  */
1432 function wfExpandUrl( $url ) {
1433         if( substr( $url, 0, 2 ) == '//' ) {
1434                 global $wgProto;
1435                 return $wgProto . ':' . $url;
1436         } elseif( substr( $url, 0, 1 ) == '/' ) {
1437                 global $wgServer;
1438                 return $wgServer . $url;
1439         } else {
1440                 return $url;
1441         }
1442 }
1443
1444 /**
1445  * Windows-compatible version of escapeshellarg()
1446  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1447  * function puts single quotes in regardless of OS.
1448  *
1449  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1450  * earlier distro releases of PHP)
1451  */
1452 function wfEscapeShellArg( ) {
1453         wfInitShellLocale();
1454
1455         $args = func_get_args();
1456         $first = true;
1457         $retVal = '';
1458         foreach ( $args as $arg ) {
1459                 if ( !$first ) {
1460                         $retVal .= ' ';
1461                 } else {
1462                         $first = false;
1463                 }
1464
1465                 if ( wfIsWindows() ) {
1466                         // Escaping for an MSVC-style command line parser and CMD.EXE
1467                         // Refs:
1468                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1469                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1470                         //  * Bug #13518
1471                         //  * CR r63214
1472                         // Double the backslashes before any double quotes. Escape the double quotes.
1473                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1474                         $arg = '';
1475                         $iteration = 0;
1476                         foreach ( $tokens as $token ) {
1477                                 if ( $iteration % 2 == 1 ) {
1478                                         // Delimiter, a double quote preceded by zero or more slashes
1479                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1480                                 } elseif ( $iteration % 4 == 2 ) {
1481                                         // ^ in $token will be outside quotes, need to be escaped
1482                                         $arg .= str_replace( '^', '^^', $token );
1483                                 } else { // $iteration % 4 == 0
1484                                         // ^ in $token will appear inside double quotes, so leave as is
1485                                         $arg .= $token;
1486                                 }
1487                                 $iteration++;
1488                         }
1489                         // Double the backslashes before the end of the string, because
1490                         // we will soon add a quote
1491                         $m = array();
1492                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1493                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1494                         }
1495
1496                         // Add surrounding quotes
1497                         $retVal .= '"' . $arg . '"';
1498                 } else {
1499                         $retVal .= escapeshellarg( $arg );
1500                 }
1501         }
1502         return $retVal;
1503 }
1504
1505 /**
1506  * wfMerge attempts to merge differences between three texts.
1507  * Returns true for a clean merge and false for failure or a conflict.
1508  */
1509 function wfMerge( $old, $mine, $yours, &$result ) {
1510         global $wgDiff3;
1511
1512         # This check may also protect against code injection in
1513         # case of broken installations.
1514         wfSuppressWarnings();
1515         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1516         wfRestoreWarnings();
1517
1518         if( !$haveDiff3 ) {
1519                 wfDebug( "diff3 not found\n" );
1520                 return false;
1521         }
1522
1523         # Make temporary files
1524         $td = wfTempDir();
1525         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1526         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1527         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1528
1529         fwrite( $oldtextFile, $old );
1530         fclose( $oldtextFile );
1531         fwrite( $mytextFile, $mine );
1532         fclose( $mytextFile );
1533         fwrite( $yourtextFile, $yours );
1534         fclose( $yourtextFile );
1535
1536         # Check for a conflict
1537         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1538                 wfEscapeShellArg( $mytextName ) . ' ' .
1539                 wfEscapeShellArg( $oldtextName ) . ' ' .
1540                 wfEscapeShellArg( $yourtextName );
1541         $handle = popen( $cmd, 'r' );
1542
1543         if( fgets( $handle, 1024 ) ) {
1544                 $conflict = true;
1545         } else {
1546                 $conflict = false;
1547         }
1548         pclose( $handle );
1549
1550         # Merge differences
1551         $cmd = $wgDiff3 . ' -a -e --merge ' .
1552                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1553         $handle = popen( $cmd, 'r' );
1554         $result = '';
1555         do {
1556                 $data = fread( $handle, 8192 );
1557                 if ( strlen( $data ) == 0 ) {
1558                         break;
1559                 }
1560                 $result .= $data;
1561         } while ( true );
1562         pclose( $handle );
1563         unlink( $mytextName );
1564         unlink( $oldtextName );
1565         unlink( $yourtextName );
1566
1567         if ( $result === '' && $old !== '' && !$conflict ) {
1568                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1569                 $conflict = true;
1570         }
1571         return !$conflict;
1572 }
1573
1574 /**
1575  * Returns unified plain-text diff of two texts.
1576  * Useful for machine processing of diffs.
1577  * @param $before String: the text before the changes.
1578  * @param $after String: the text after the changes.
1579  * @param $params String: command-line options for the diff command.
1580  * @return String: unified diff of $before and $after
1581  */
1582 function wfDiff( $before, $after, $params = '-u' ) {
1583         if ( $before == $after ) {
1584                 return '';
1585         }
1586
1587         global $wgDiff;
1588         wfSuppressWarnings();
1589         $haveDiff = $wgDiff && file_exists( $wgDiff );
1590         wfRestoreWarnings();
1591
1592         # This check may also protect against code injection in
1593         # case of broken installations.
1594         if( !$haveDiff ) {
1595                 wfDebug( "diff executable not found\n" );
1596                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1597                 $format = new UnifiedDiffFormatter();
1598                 return $format->format( $diffs );
1599         }
1600
1601         # Make temporary files
1602         $td = wfTempDir();
1603         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1604         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1605
1606         fwrite( $oldtextFile, $before );
1607         fclose( $oldtextFile );
1608         fwrite( $newtextFile, $after );
1609         fclose( $newtextFile );
1610
1611         // Get the diff of the two files
1612         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1613
1614         $h = popen( $cmd, 'r' );
1615
1616         $diff = '';
1617
1618         do {
1619                 $data = fread( $h, 8192 );
1620                 if ( strlen( $data ) == 0 ) {
1621                         break;
1622                 }
1623                 $diff .= $data;
1624         } while ( true );
1625
1626         // Clean up
1627         pclose( $h );
1628         unlink( $oldtextName );
1629         unlink( $newtextName );
1630
1631         // Kill the --- and +++ lines. They're not useful.
1632         $diff_lines = explode( "\n", $diff );
1633         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1634                 unset( $diff_lines[0] );
1635         }
1636         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1637                 unset( $diff_lines[1] );
1638         }
1639
1640         $diff = implode( "\n", $diff_lines );
1641
1642         return $diff;
1643 }
1644
1645 /**
1646  * A wrapper around the PHP function var_export().
1647  * Either print it or add it to the regular output ($wgOut).
1648  *
1649  * @param $var A PHP variable to dump.
1650  */
1651 function wfVarDump( $var ) {
1652         global $wgOut;
1653         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1654         if ( headers_sent() || !@is_object( $wgOut ) ) {
1655                 print $s;
1656         } else {
1657                 $wgOut->addHTML( $s );
1658         }
1659 }
1660
1661 /**
1662  * Provide a simple HTTP error.
1663  */
1664 function wfHttpError( $code, $label, $desc ) {
1665         global $wgOut;
1666         $wgOut->disable();
1667         header( "HTTP/1.0 $code $label" );
1668         header( "Status: $code $label" );
1669         $wgOut->sendCacheControl();
1670
1671         header( 'Content-type: text/html; charset=utf-8' );
1672         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1673                 '<html><head><title>' .
1674                 htmlspecialchars( $label ) .
1675                 '</title></head><body><h1>' .
1676                 htmlspecialchars( $label ) .
1677                 '</h1><p>' .
1678                 nl2br( htmlspecialchars( $desc ) ) .
1679                 "</p></body></html>\n";
1680 }
1681
1682 /**
1683  * Clear away any user-level output buffers, discarding contents.
1684  *
1685  * Suitable for 'starting afresh', for instance when streaming
1686  * relatively large amounts of data without buffering, or wanting to
1687  * output image files without ob_gzhandler's compression.
1688  *
1689  * The optional $resetGzipEncoding parameter controls suppression of
1690  * the Content-Encoding header sent by ob_gzhandler; by default it
1691  * is left. See comments for wfClearOutputBuffers() for why it would
1692  * be used.
1693  *
1694  * Note that some PHP configuration options may add output buffer
1695  * layers which cannot be removed; these are left in place.
1696  *
1697  * @param $resetGzipEncoding Bool
1698  */
1699 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1700         if( $resetGzipEncoding ) {
1701                 // Suppress Content-Encoding and Content-Length
1702                 // headers from 1.10+s wfOutputHandler
1703                 global $wgDisableOutputCompression;
1704                 $wgDisableOutputCompression = true;
1705         }
1706         while( $status = ob_get_status() ) {
1707                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1708                         // Probably from zlib.output_compression or other
1709                         // PHP-internal setting which can't be removed.
1710                         //
1711                         // Give up, and hope the result doesn't break
1712                         // output behavior.
1713                         break;
1714                 }
1715                 if( !ob_end_clean() ) {
1716                         // Could not remove output buffer handler; abort now
1717                         // to avoid getting in some kind of infinite loop.
1718                         break;
1719                 }
1720                 if( $resetGzipEncoding ) {
1721                         if( $status['name'] == 'ob_gzhandler' ) {
1722                                 // Reset the 'Content-Encoding' field set by this handler
1723                                 // so we can start fresh.
1724                                 header( 'Content-Encoding:' );
1725                                 break;
1726                         }
1727                 }
1728         }
1729 }
1730
1731 /**
1732  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1733  *
1734  * Clear away output buffers, but keep the Content-Encoding header
1735  * produced by ob_gzhandler, if any.
1736  *
1737  * This should be used for HTTP 304 responses, where you need to
1738  * preserve the Content-Encoding header of the real result, but
1739  * also need to suppress the output of ob_gzhandler to keep to spec
1740  * and avoid breaking Firefox in rare cases where the headers and
1741  * body are broken over two packets.
1742  */
1743 function wfClearOutputBuffers() {
1744         wfResetOutputBuffers( false );
1745 }
1746
1747 /**
1748  * Converts an Accept-* header into an array mapping string values to quality
1749  * factors
1750  */
1751 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1752         # No arg means accept anything (per HTTP spec)
1753         if( !$accept ) {
1754                 return array( $def => 1.0 );
1755         }
1756
1757         $prefs = array();
1758
1759         $parts = explode( ',', $accept );
1760
1761         foreach( $parts as $part ) {
1762                 # FIXME: doesn't deal with params like 'text/html; level=1'
1763                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1764                 $match = array();
1765                 if( !isset( $qpart ) ) {
1766                         $prefs[$value] = 1.0;
1767                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1768                         $prefs[$value] = floatval( $match[1] );
1769                 }
1770         }
1771
1772         return $prefs;
1773 }
1774
1775 /**
1776  * Checks if a given MIME type matches any of the keys in the given
1777  * array. Basic wildcards are accepted in the array keys.
1778  *
1779  * Returns the matching MIME type (or wildcard) if a match, otherwise
1780  * NULL if no match.
1781  *
1782  * @param $type String
1783  * @param $avail Array
1784  * @return string
1785  * @private
1786  */
1787 function mimeTypeMatch( $type, $avail ) {
1788         if( array_key_exists( $type, $avail ) ) {
1789                 return $type;
1790         } else {
1791                 $parts = explode( '/', $type );
1792                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1793                         return $parts[0] . '/*';
1794                 } elseif( array_key_exists( '*/*', $avail ) ) {
1795                         return '*/*';
1796                 } else {
1797                         return null;
1798                 }
1799         }
1800 }
1801
1802 /**
1803  * Returns the 'best' match between a client's requested internet media types
1804  * and the server's list of available types. Each list should be an associative
1805  * array of type to preference (preference is a float between 0.0 and 1.0).
1806  * Wildcards in the types are acceptable.
1807  *
1808  * @param $cprefs Array: client's acceptable type list
1809  * @param $sprefs Array: server's offered types
1810  * @return string
1811  *
1812  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1813  * XXX: generalize to negotiate other stuff
1814  */
1815 function wfNegotiateType( $cprefs, $sprefs ) {
1816         $combine = array();
1817
1818         foreach( array_keys($sprefs) as $type ) {
1819                 $parts = explode( '/', $type );
1820                 if( $parts[1] != '*' ) {
1821                         $ckey = mimeTypeMatch( $type, $cprefs );
1822                         if( $ckey ) {
1823                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1824                         }
1825                 }
1826         }
1827
1828         foreach( array_keys( $cprefs ) as $type ) {
1829                 $parts = explode( '/', $type );
1830                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1831                         $skey = mimeTypeMatch( $type, $sprefs );
1832                         if( $skey ) {
1833                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1834                         }
1835                 }
1836         }
1837
1838         $bestq = 0;
1839         $besttype = null;
1840
1841         foreach( array_keys( $combine ) as $type ) {
1842                 if( $combine[$type] > $bestq ) {
1843                         $besttype = $type;
1844                         $bestq = $combine[$type];
1845                 }
1846         }
1847
1848         return $besttype;
1849 }
1850
1851 /**
1852  * Array lookup
1853  * Returns an array where the values in the first array are replaced by the
1854  * values in the second array with the corresponding keys
1855  *
1856  * @return array
1857  */
1858 function wfArrayLookup( $a, $b ) {
1859         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1860 }
1861
1862 /**
1863  * Convenience function; returns MediaWiki timestamp for the present time.
1864  * @return string
1865  */
1866 function wfTimestampNow() {
1867         # return NOW
1868         return wfTimestamp( TS_MW, time() );
1869 }
1870
1871 /**
1872  * Reference-counted warning suppression
1873  */
1874 function wfSuppressWarnings( $end = false ) {
1875         static $suppressCount = 0;
1876         static $originalLevel = false;
1877
1878         if ( $end ) {
1879                 if ( $suppressCount ) {
1880                         --$suppressCount;
1881                         if ( !$suppressCount ) {
1882                                 error_reporting( $originalLevel );
1883                         }
1884                 }
1885         } else {
1886                 if ( !$suppressCount ) {
1887                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE ) );
1888                 }
1889                 ++$suppressCount;
1890         }
1891 }
1892
1893 /**
1894  * Restore error level to previous value
1895  */
1896 function wfRestoreWarnings() {
1897         wfSuppressWarnings( true );
1898 }
1899
1900 # Autodetect, convert and provide timestamps of various types
1901
1902 /**
1903  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1904  */
1905 define( 'TS_UNIX', 0 );
1906
1907 /**
1908  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1909  */
1910 define( 'TS_MW', 1 );
1911
1912 /**
1913  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1914  */
1915 define( 'TS_DB', 2 );
1916
1917 /**
1918  * RFC 2822 format, for E-mail and HTTP headers
1919  */
1920 define( 'TS_RFC2822', 3 );
1921
1922 /**
1923  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1924  *
1925  * This is used by Special:Export
1926  */
1927 define( 'TS_ISO_8601', 4 );
1928
1929 /**
1930  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1931  *
1932  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1933  *       DateTime tag and page 36 for the DateTimeOriginal and
1934  *       DateTimeDigitized tags.
1935  */
1936 define( 'TS_EXIF', 5 );
1937
1938 /**
1939  * Oracle format time.
1940  */
1941 define( 'TS_ORACLE', 6 );
1942
1943 /**
1944  * Postgres format time.
1945  */
1946 define( 'TS_POSTGRES', 7 );
1947
1948 /**
1949  * DB2 format time
1950  */
1951 define( 'TS_DB2', 8 );
1952
1953 /**
1954  * ISO 8601 basic format with no timezone: 19860209T200000Z
1955  *
1956  * This is used by ResourceLoader
1957  */
1958 define( 'TS_ISO_8601_BASIC', 9 );
1959
1960 /**
1961  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
1962  *                    function will autodetect which format is supplied and act
1963  *                    accordingly.
1964  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
1965  * @return Mixed: String / false The same date in the format specified in $outputtype or false
1966  */
1967 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1968         $uts = 0;
1969         $da = array();
1970         $strtime = '';
1971
1972         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
1973                 $uts = time();
1974                 $strtime = "@$uts";
1975         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1976                 # TS_DB
1977         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1978                 # TS_EXIF
1979         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
1980                 # TS_MW
1981         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
1982                 # TS_UNIX
1983                 $uts = $ts;
1984                 $strtime = "@$ts"; // Undocumented?
1985         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
1986                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
1987                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1988                                 str_replace( '+00:00', 'UTC', $ts ) );
1989         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1990                 # TS_ISO_8601
1991         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1992                 #TS_ISO_8601_BASIC
1993         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
1994                 # TS_POSTGRES
1995         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
1996                 # TS_POSTGRES
1997         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
1998                 # TS_DB2
1999         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2000                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2001                                                         '[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d/S', $ts ) ) { # hh:mm:ss
2002                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2003                 # The regex is a superset of rfc2822 for readability
2004                 $strtime = strtok( $ts, ';' );
2005         } elseif ( preg_match( '/^[A-Z][a-z]{5,8}, \d\d-[A-Z][a-z]{2}-\d{2} \d\d:\d\d:\d\d/', $ts ) ) {
2006                 # TS_RFC850
2007                 $strtime = $ts;
2008         } elseif ( preg_match( '/^[A-Z][a-z]{2} [A-Z][a-z]{2} +\d{1,2} \d\d:\d\d:\d\d \d{4}/', $ts ) ) {
2009                 # asctime
2010                 $strtime = $ts;
2011         } else {
2012                 # Bogus value...
2013                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2014
2015                 return false;
2016         }
2017
2018
2019
2020         static $formats = array(
2021                 TS_UNIX => 'U',
2022                 TS_MW => 'YmdHis',
2023                 TS_DB => 'Y-m-d H:i:s',
2024                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2025                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2026                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2027                 TS_RFC2822 => 'D, d M Y H:i:s',
2028                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2029                 TS_POSTGRES => 'Y-m-d H:i:s',
2030                 TS_DB2 => 'Y-m-d H:i:s',
2031         );
2032
2033         if ( !isset( $formats[$outputtype] ) ) {
2034                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2035         }
2036
2037         if ( function_exists( "date_create" ) ) {
2038                 if ( count( $da ) ) {
2039                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2040                                 (int)$da[1], (int)$da[2], (int)$da[3],
2041                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2042
2043                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2044                 } elseif ( $strtime ) {
2045                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2046                 } else {
2047                         return false;
2048                 }
2049
2050                 if ( !$d ) {
2051                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2052                         return false;
2053                 }
2054
2055                 $output = $d->format( $formats[$outputtype] );
2056         } else {
2057                 if ( count( $da ) ) {
2058                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2059                         // We may want to handle that explicitly at some point
2060                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2061                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2062                 } elseif ( $strtime ) {
2063                         $uts = strtotime( $strtime );
2064                 }
2065
2066                 if ( $uts === false ) {
2067                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2068                         return false;
2069                 }
2070
2071                 if ( TS_UNIX == $outputtype ) {
2072                         return $uts;
2073                 }
2074                 $output = gmdate( $formats[$outputtype], $uts );
2075         }
2076
2077         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2078                 $output .= ' GMT';
2079         }
2080
2081         return $output;
2082 }
2083
2084 /**
2085  * Return a formatted timestamp, or null if input is null.
2086  * For dealing with nullable timestamp columns in the database.
2087  * @param $outputtype Integer
2088  * @param $ts String
2089  * @return String
2090  */
2091 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2092         if( is_null( $ts ) ) {
2093                 return null;
2094         } else {
2095                 return wfTimestamp( $outputtype, $ts );
2096         }
2097 }
2098
2099 /**
2100  * Check if the operating system is Windows
2101  *
2102  * @return Bool: true if it's Windows, False otherwise.
2103  */
2104 function wfIsWindows() {
2105         static $isWindows = null;
2106         if ( $isWindows === null ) {
2107                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2108         }
2109         return $isWindows;
2110 }
2111
2112 /**
2113  * Swap two variables
2114  */
2115 function swap( &$x, &$y ) {
2116         $z = $x;
2117         $x = $y;
2118         $y = $z;
2119 }
2120
2121 function wfGetCachedNotice( $name ) {
2122         global $wgOut, $wgRenderHashAppend, $parserMemc;
2123         $fname = 'wfGetCachedNotice';
2124         wfProfileIn( $fname );
2125
2126         $needParse = false;
2127
2128         if( $name === 'default' ) {
2129                 // special case
2130                 global $wgSiteNotice;
2131                 $notice = $wgSiteNotice;
2132                 if( empty( $notice ) ) {
2133                         wfProfileOut( $fname );
2134                         return false;
2135                 }
2136         } else {
2137                 $notice = wfMsgForContentNoTrans( $name );
2138                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
2139                         wfProfileOut( $fname );
2140                         return( false );
2141                 }
2142         }
2143
2144         // Use the extra hash appender to let eg SSL variants separately cache.
2145         $key = wfMemcKey( $name . $wgRenderHashAppend );
2146         $cachedNotice = $parserMemc->get( $key );
2147         if( is_array( $cachedNotice ) ) {
2148                 if( md5( $notice ) == $cachedNotice['hash'] ) {
2149                         $notice = $cachedNotice['html'];
2150                 } else {
2151                         $needParse = true;
2152                 }
2153         } else {
2154                 $needParse = true;
2155         }
2156
2157         if( $needParse ) {
2158                 if( is_object( $wgOut ) ) {
2159                         $parsed = $wgOut->parse( $notice );
2160                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
2161                         $notice = $parsed;
2162                 } else {
2163                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' . "\n" );
2164                         $notice = '';
2165                 }
2166         }
2167         $notice = '<div id="localNotice">' .$notice . '</div>';
2168         wfProfileOut( $fname );
2169         return $notice;
2170 }
2171
2172 function wfGetNamespaceNotice() {
2173         global $wgTitle;
2174
2175         # Paranoia
2176         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) ) {
2177                 return '';
2178         }
2179
2180         $fname = 'wfGetNamespaceNotice';
2181         wfProfileIn( $fname );
2182
2183         $key = 'namespacenotice-' . $wgTitle->getNsText();
2184         $namespaceNotice = wfGetCachedNotice( $key );
2185         if ( $namespaceNotice && substr( $namespaceNotice, 0, 7 ) != '<p>&lt;' ) {
2186                 $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . '</div>';
2187         } else {
2188                 $namespaceNotice = '';
2189         }
2190
2191         wfProfileOut( $fname );
2192         return $namespaceNotice;
2193 }
2194
2195 function wfGetSiteNotice() {
2196         global $wgUser;
2197         $fname = 'wfGetSiteNotice';
2198         wfProfileIn( $fname );
2199         $siteNotice = '';
2200
2201         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
2202                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
2203                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
2204                 } else {
2205                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
2206                         if( !$anonNotice ) {
2207                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
2208                         } else {
2209                                 $siteNotice = $anonNotice;
2210                         }
2211                 }
2212                 if( !$siteNotice ) {
2213                         $siteNotice = wfGetCachedNotice( 'default' );
2214                 }
2215         }
2216
2217         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
2218         wfProfileOut( $fname );
2219         return $siteNotice;
2220 }
2221
2222 /**
2223  * BC wrapper for MimeMagic::singleton()
2224  * @deprecated No longer needed as of 1.17 (r68836). Remove in 1.19.
2225  */
2226 function &wfGetMimeMagic() {
2227         wfDeprecated( __FUNCTION__ );
2228         return MimeMagic::singleton();
2229 }
2230
2231 /**
2232  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2233  * TEMP environment variables are then checked in sequence, and if none are set
2234  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2235  * or C:\Windows\Temp for Windows and hope for the best.
2236  * It is common to call it with tempnam().
2237  *
2238  * NOTE: When possible, use instead the tmpfile() function to create
2239  * temporary files to avoid race conditions on file creation, etc.
2240  *
2241  * @return String
2242  */
2243 function wfTempDir() {
2244         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2245                 $tmp = getenv( $var );
2246                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2247                         return $tmp;
2248                 }
2249         }
2250         if( function_exists( 'sys_get_temp_dir' ) ) {
2251                 return sys_get_temp_dir();
2252         }
2253         # Usual defaults
2254         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2255 }
2256
2257 /**
2258  * Make directory, and make all parent directories if they don't exist
2259  *
2260  * @param $dir String: full path to directory to create
2261  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2262  * @param $caller String: optional caller param for debugging.
2263  * @return bool
2264  */
2265 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2266         global $wgDirectoryMode;
2267
2268         if ( !is_null( $caller ) ) {
2269                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2270         }
2271
2272         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2273                 return true;
2274         }
2275
2276         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2277
2278         if ( is_null( $mode ) ) {
2279                 $mode = $wgDirectoryMode;
2280         }
2281
2282         // Turn off the normal warning, we're doing our own below
2283         wfSuppressWarnings();
2284         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2285         wfRestoreWarnings();
2286
2287         if( !$ok ) {
2288                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2289                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2290         }
2291         return $ok;
2292 }
2293
2294 /**
2295  * Increment a statistics counter
2296  */
2297 function wfIncrStats( $key ) {
2298         global $wgStatsMethod;
2299
2300         if( $wgStatsMethod == 'udp' ) {
2301                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
2302                 static $socket;
2303                 if ( !$socket ) {
2304                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2305                         $statline = "stats/{$wgDBname} - 1 1 1 1 1 -total\n";
2306                         socket_sendto(
2307                                 $socket,
2308                                 $statline,
2309                                 strlen( $statline ),
2310                                 0,
2311                                 $wgUDPProfilerHost,
2312                                 $wgUDPProfilerPort
2313                         );
2314                 }
2315                 $statline = "stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
2316                 wfSuppressWarnings();
2317                 socket_sendto(
2318                         $socket,
2319                         $statline,
2320                         strlen( $statline ),
2321                         0,
2322                         $wgUDPProfilerHost,
2323                         $wgUDPProfilerPort
2324                 );
2325                 wfRestoreWarnings();
2326         } elseif( $wgStatsMethod == 'cache' ) {
2327                 global $wgMemc;
2328                 $key = wfMemcKey( 'stats', $key );
2329                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2330                         $wgMemc->add( $key, 1 );
2331                 }
2332         } else {
2333                 // Disabled
2334         }
2335 }
2336
2337 /**
2338  * @param $nr Mixed: the number to format
2339  * @param $acc Integer: the number of digits after the decimal point, default 2
2340  * @param $round Boolean: whether or not to round the value, default true
2341  * @return float
2342  */
2343 function wfPercent( $nr, $acc = 2, $round = true ) {
2344         $ret = sprintf( "%.${acc}f", $nr );
2345         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2346 }
2347
2348 /**
2349  * Encrypt a username/password.
2350  *
2351  * @param $userid Integer: ID of the user
2352  * @param $password String: password of the user
2353  * @return String: hashed password
2354  * @deprecated Use User::crypt() or User::oldCrypt() instead
2355  */
2356 function wfEncryptPassword( $userid, $password ) {
2357         wfDeprecated(__FUNCTION__);
2358         # Just wrap around User::oldCrypt()
2359         return User::oldCrypt( $password, $userid );
2360 }
2361
2362 /**
2363  * Appends to second array if $value differs from that in $default
2364  */
2365 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2366         if ( is_null( $changed ) ) {
2367                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
2368         }
2369         if ( $default[$key] !== $value ) {
2370                 $changed[$key] = $value;
2371         }
2372 }
2373
2374 /**
2375  * Since wfMsg() and co suck, they don't return false if the message key they
2376  * looked up didn't exist but a XHTML string, this function checks for the
2377  * nonexistance of messages by looking at wfMsg() output
2378  *
2379  * @param $key      String: the message key looked up
2380  * @return Boolean True if the message *doesn't* exist.
2381  */
2382 function wfEmptyMsg( $key ) {
2383         global $wgMessageCache;
2384         return $wgMessageCache->get( $key, /*useDB*/true, /*content*/false ) === false;
2385 }
2386
2387 /**
2388  * Find out whether or not a mixed variable exists in a string
2389  *
2390  * @param $needle String
2391  * @param $str String
2392  * @return Boolean
2393  */
2394 function in_string( $needle, $str ) {
2395         return strpos( $str, $needle ) !== false;
2396 }
2397
2398 function wfSpecialList( $page, $details ) {
2399         global $wgContLang;
2400         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2401         return $page . $details;
2402 }
2403
2404 /**
2405  * Returns a regular expression of url protocols
2406  *
2407  * @return String
2408  */
2409 function wfUrlProtocols() {
2410         global $wgUrlProtocols;
2411
2412         static $retval = null;
2413         if ( !is_null( $retval ) ) {
2414                 return $retval;
2415         }
2416
2417         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2418         // with LocalSettings files from 1.5
2419         if ( is_array( $wgUrlProtocols ) ) {
2420                 $protocols = array();
2421                 foreach ( $wgUrlProtocols as $protocol ) {
2422                         $protocols[] = preg_quote( $protocol, '/' );
2423                 }
2424
2425                 $retval = implode( '|', $protocols );
2426         } else {
2427                 $retval = $wgUrlProtocols;
2428         }
2429         return $retval;
2430 }
2431
2432 /**
2433  * Safety wrapper around ini_get() for boolean settings.
2434  * The values returned from ini_get() are pre-normalized for settings
2435  * set via php.ini or php_flag/php_admin_flag... but *not*
2436  * for those set via php_value/php_admin_value.
2437  *
2438  * It's fairly common for people to use php_value instead of php_flag,
2439  * which can leave you with an 'off' setting giving a false positive
2440  * for code that just takes the ini_get() return value as a boolean.
2441  *
2442  * To make things extra interesting, setting via php_value accepts
2443  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2444  * Unrecognized values go false... again opposite PHP's own coercion
2445  * from string to bool.
2446  *
2447  * Luckily, 'properly' set settings will always come back as '0' or '1',
2448  * so we only have to worry about them and the 'improper' settings.
2449  *
2450  * I frickin' hate PHP... :P
2451  *
2452  * @param $setting String
2453  * @return Bool
2454  */
2455 function wfIniGetBool( $setting ) {
2456         $val = ini_get( $setting );
2457         // 'on' and 'true' can't have whitespace around them, but '1' can.
2458         return strtolower( $val ) == 'on'
2459                 || strtolower( $val ) == 'true'
2460                 || strtolower( $val ) == 'yes'
2461                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2462 }
2463
2464 /**
2465  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2466  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2467  *
2468  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2469  *                          should be omitted
2470  * @return Bool - Whether or not the extension is loaded
2471  */
2472 function wfDl( $extension ) {
2473         if( extension_loaded( $extension ) ) {
2474                 return true;
2475         }
2476
2477         $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2478                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2479
2480         if( $canDl ) {
2481                 wfSuppressWarnings();
2482                 dl( $extension . '.' . PHP_SHLIB_SUFFIX );
2483                 wfRestoreWarnings();
2484         }
2485         return extension_loaded( $extension );
2486 }
2487
2488 /**
2489  * Execute a shell command, with time and memory limits mirrored from the PHP
2490  * configuration if supported.
2491  * @param $cmd String Command line, properly escaped for shell.
2492  * @param &$retval optional, will receive the program's exit code.
2493  *                 (non-zero is usually failure)
2494  * @param $environ Array optional environment variables which should be
2495  *                 added to the executed command environment.
2496  * @return collected stdout as a string (trailing newlines stripped)
2497  */
2498 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2499         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2500
2501         static $disabled;
2502         if ( is_null( $disabled ) ) {
2503                 $disabled = false;
2504                 if( wfIniGetBool( 'safe_mode' ) ) {
2505                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2506                         $disabled = 'safemode';
2507                 } else {
2508                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2509                         $functions = array_map( 'trim', $functions );
2510                         $functions = array_map( 'strtolower', $functions );
2511                         if ( in_array( 'passthru', $functions ) ) {
2512                                 wfDebug( "passthru is in disabled_functions\n" );
2513                                 $disabled = 'passthru';
2514                         }
2515                 }
2516         }
2517         if ( $disabled ) {
2518                 $retval = 1;
2519                 return $disabled == 'safemode' ?
2520                         'Unable to run external programs in safe mode.' :
2521                         'Unable to run external programs, passthru() is disabled.';
2522         }
2523
2524         wfInitShellLocale();
2525
2526         $envcmd = '';
2527         foreach( $environ as $k => $v ) {
2528                 if ( wfIsWindows() ) {
2529                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2530                          * appear in the environment variable, so we must use carat escaping as documented in
2531                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2532                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2533                          * are listed there but doesn't appear to need it.
2534                          */
2535                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2536                 } else {
2537                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2538                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2539                          */
2540                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2541                 }
2542         }
2543         $cmd = $envcmd . $cmd;
2544
2545         if ( wfIsWindows() ) {
2546                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2547                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2548                 {
2549                         # Hack to work around PHP's flawed invocation of cmd.exe
2550                         # http://news.php.net/php.internals/21796
2551                         # Windows 9x doesn't accept any kind of quotes
2552                         $cmd = '"' . $cmd . '"';
2553                 }
2554         } elseif ( php_uname( 's' ) == 'Linux' ) {
2555                 $time = intval( $wgMaxShellTime );
2556                 $mem = intval( $wgMaxShellMemory );
2557                 $filesize = intval( $wgMaxShellFileSize );
2558
2559                 if ( $time > 0 && $mem > 0 ) {
2560                         $script = "$IP/bin/ulimit4.sh";
2561                         if ( is_executable( $script ) ) {
2562                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2563                         }
2564                 }
2565         }
2566         wfDebug( "wfShellExec: $cmd\n" );
2567
2568         $retval = 1; // error by default?
2569         ob_start();
2570         passthru( $cmd, $retval );
2571         $output = ob_get_contents();
2572         ob_end_clean();
2573
2574         if ( $retval == 127 ) {
2575                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2576         }
2577         return $output;
2578 }
2579
2580 /**
2581  * Workaround for http://bugs.php.net/bug.php?id=45132
2582  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2583  */
2584 function wfInitShellLocale() {
2585         static $done = false;
2586         if ( $done ) {
2587                 return;
2588         }
2589         $done = true;
2590         global $wgShellLocale;
2591         if ( !wfIniGetBool( 'safe_mode' ) ) {
2592                 putenv( "LC_CTYPE=$wgShellLocale" );
2593                 setlocale( LC_CTYPE, $wgShellLocale );
2594         }
2595 }
2596
2597 /**
2598  * This function works like "use VERSION" in Perl, the program will die with a
2599  * backtrace if the current version of PHP is less than the version provided
2600  *
2601  * This is useful for extensions which due to their nature are not kept in sync
2602  * with releases, and might depend on other versions of PHP than the main code
2603  *
2604  * Note: PHP might die due to parsing errors in some cases before it ever
2605  *       manages to call this function, such is life
2606  *
2607  * @see perldoc -f use
2608  *
2609  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2610  *                 a float
2611  */
2612 function wfUsePHP( $req_ver ) {
2613         $php_ver = PHP_VERSION;
2614
2615         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2616                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2617         }
2618 }
2619
2620 /**
2621  * This function works like "use VERSION" in Perl except it checks the version
2622  * of MediaWiki, the program will die with a backtrace if the current version
2623  * of MediaWiki is less than the version provided.
2624  *
2625  * This is useful for extensions which due to their nature are not kept in sync
2626  * with releases
2627  *
2628  * @see perldoc -f use
2629  *
2630  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2631  *                 a float
2632  */
2633 function wfUseMW( $req_ver ) {
2634         global $wgVersion;
2635
2636         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2637                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2638         }
2639 }
2640
2641 /**
2642  * Return the final portion of a pathname.
2643  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2644  * http://bugs.php.net/bug.php?id=33898
2645  *
2646  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2647  * We'll consider it so always, as we don't want \s in our Unix paths either.
2648  *
2649  * @param $path String
2650  * @param $suffix String: to remove if present
2651  * @return String
2652  */
2653 function wfBaseName( $path, $suffix = '' ) {
2654         $encSuffix = ( $suffix == '' )
2655                 ? ''
2656                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2657         $matches = array();
2658         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2659                 return $matches[1];
2660         } else {
2661                 return '';
2662         }
2663 }
2664
2665 /**
2666  * Generate a relative path name to the given file.
2667  * May explode on non-matching case-insensitive paths,
2668  * funky symlinks, etc.
2669  *
2670  * @param $path String: absolute destination path including target filename
2671  * @param $from String: Absolute source path, directory only
2672  * @return String
2673  */
2674 function wfRelativePath( $path, $from ) {
2675         // Normalize mixed input on Windows...
2676         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2677         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2678
2679         // Trim trailing slashes -- fix for drive root
2680         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2681         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2682
2683         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2684         $against = explode( DIRECTORY_SEPARATOR, $from );
2685
2686         if( $pieces[0] !== $against[0] ) {
2687                 // Non-matching Windows drive letters?
2688                 // Return a full path.
2689                 return $path;
2690         }
2691
2692         // Trim off common prefix
2693         while( count( $pieces ) && count( $against )
2694                 && $pieces[0] == $against[0] ) {
2695                 array_shift( $pieces );
2696                 array_shift( $against );
2697         }
2698
2699         // relative dots to bump us to the parent
2700         while( count( $against ) ) {
2701                 array_unshift( $pieces, '..' );
2702                 array_shift( $against );
2703         }
2704
2705         array_push( $pieces, wfBaseName( $path ) );
2706
2707         return implode( DIRECTORY_SEPARATOR, $pieces );
2708 }
2709
2710 /**
2711  * Backwards array plus for people who haven't bothered to read the PHP manual
2712  * XXX: will not darn your socks for you.
2713  *
2714  * @param $array1 Array
2715  * @param [$array2, [...]] Arrays
2716  * @return Array
2717  */
2718 function wfArrayMerge( $array1/* ... */ ) {
2719         $args = func_get_args();
2720         $args = array_reverse( $args, true );
2721         $out = array();
2722         foreach ( $args as $arg ) {
2723                 $out += $arg;
2724         }
2725         return $out;
2726 }
2727
2728 /**
2729  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
2730  * e.g.
2731  *      wfMergeErrorArrays(
2732  *              array( array( 'x' ) ),
2733  *              array( array( 'x', '2' ) ),
2734  *              array( array( 'x' ) ),
2735  *              array( array( 'y') )
2736  *      );
2737  * returns:
2738  *              array(
2739  *              array( 'x', '2' ),
2740  *              array( 'x' ),
2741  *              array( 'y' )
2742  *      )
2743  */
2744 function wfMergeErrorArrays( /*...*/ ) {
2745         $args = func_get_args();
2746         $out = array();
2747         foreach ( $args as $errors ) {
2748                 foreach ( $errors as $params ) {
2749                         # FIXME: sometimes get nested arrays for $params,
2750                         # which leads to E_NOTICEs
2751                         $spec = implode( "\t", $params );
2752                         $out[$spec] = $params;
2753                 }
2754         }
2755         return array_values( $out );
2756 }
2757
2758 /**
2759  * parse_url() work-alike, but non-broken.  Differences:
2760  *
2761  * 1) Does not raise warnings on bad URLs (just returns false)
2762  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2763  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2764  *
2765  * @param $url String: a URL to parse
2766  * @return Array: bits of the URL in an associative array, per PHP docs
2767  */
2768 function wfParseUrl( $url ) {
2769         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2770         wfSuppressWarnings();
2771         $bits = parse_url( $url );
2772         wfRestoreWarnings();
2773         if ( !$bits ) {
2774                 return false;
2775         }
2776
2777         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2778         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2779                 $bits['delimiter'] = '://';
2780         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2781                 $bits['delimiter'] = ':';
2782                 // parse_url detects for news: and mailto: the host part of an url as path
2783                 // We have to correct this wrong detection
2784                 if ( isset( $bits['path'] ) ) {
2785                         $bits['host'] = $bits['path'];
2786                         $bits['path'] = '';
2787                 }
2788         } else {
2789                 return false;
2790         }
2791
2792         return $bits;
2793 }
2794
2795 /**
2796  * Make a URL index, appropriate for the el_index field of externallinks.
2797  */
2798 function wfMakeUrlIndex( $url ) {
2799         $bits = wfParseUrl( $url );
2800
2801         // Reverse the labels in the hostname, convert to lower case
2802         // For emails reverse domainpart only
2803         if ( $bits['scheme'] == 'mailto' ) {
2804                 $mailparts = explode( '@', $bits['host'], 2 );
2805                 if ( count( $mailparts ) === 2 ) {
2806                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2807                 } else {
2808                         // No domain specified, don't mangle it
2809                         $domainpart = '';
2810                 }
2811                 $reversedHost = $domainpart . '@' . $mailparts[0];
2812         } else {
2813                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2814         }
2815         // Add an extra dot to the end
2816         // Why? Is it in wrong place in mailto links?
2817         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2818                 $reversedHost .= '.';
2819         }
2820         // Reconstruct the pseudo-URL
2821         $prot = $bits['scheme'];
2822         $index = $prot . $bits['delimiter'] . $reversedHost;
2823         // Leave out user and password. Add the port, path, query and fragment
2824         if ( isset( $bits['port'] ) ) {
2825                 $index .= ':' . $bits['port'];
2826         }
2827         if ( isset( $bits['path'] ) ) {
2828                 $index .= $bits['path'];
2829         } else {
2830                 $index .= '/';
2831         }
2832         if ( isset( $bits['query'] ) ) {
2833                 $index .= '?' . $bits['query'];
2834         }
2835         if ( isset( $bits['fragment'] ) ) {
2836                 $index .= '#' . $bits['fragment'];
2837         }
2838         return $index;
2839 }
2840
2841 /**
2842  * Do any deferred updates and clear the list
2843  *
2844  * @param $commit String: set to 'commit' to commit after every update to
2845  *                prevent lock contention
2846  */
2847 function wfDoUpdates( $commit = '' ) {
2848         global $wgDeferredUpdateList;
2849
2850         wfProfileIn( __METHOD__ );
2851
2852         // No need to get master connections in case of empty updates array
2853         if ( !count( $wgDeferredUpdateList ) ) {
2854                 wfProfileOut( __METHOD__ );
2855                 return;
2856         }
2857
2858         $doCommit = $commit == 'commit';
2859         if ( $doCommit ) {
2860                 $dbw = wfGetDB( DB_MASTER );
2861         }
2862
2863         foreach ( $wgDeferredUpdateList as $update ) {
2864                 $update->doUpdate();
2865
2866                 if ( $doCommit && $dbw->trxLevel() ) {
2867                         $dbw->commit();
2868                 }
2869         }
2870
2871         $wgDeferredUpdateList = array();
2872         wfProfileOut( __METHOD__ );
2873 }
2874
2875 /**
2876  * Convert an arbitrarily-long digit string from one numeric base
2877  * to another, optionally zero-padding to a minimum column width.
2878  *
2879  * Supports base 2 through 36; digit values 10-36 are represented
2880  * as lowercase letters a-z. Input is case-insensitive.
2881  *
2882  * @param $input String: of digits
2883  * @param $sourceBase Integer: 2-36
2884  * @param $destBase Integer: 2-36
2885  * @param $pad Integer: 1 or greater
2886  * @param $lowercase Boolean
2887  * @return String or false on invalid input
2888  */
2889 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2890         $input = strval( $input );
2891         if( $sourceBase < 2 ||
2892                 $sourceBase > 36 ||
2893                 $destBase < 2 ||
2894                 $destBase > 36 ||
2895                 $pad < 1 ||
2896                 $sourceBase != intval( $sourceBase ) ||
2897                 $destBase != intval( $destBase ) ||
2898                 $pad != intval( $pad ) ||
2899                 !is_string( $input ) ||
2900                 $input == '' ) {
2901                 return false;
2902         }
2903         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2904         $inDigits = array();
2905         $outChars = '';
2906
2907         // Decode and validate input string
2908         $input = strtolower( $input );
2909         for( $i = 0; $i < strlen( $input ); $i++ ) {
2910                 $n = strpos( $digitChars, $input{$i} );
2911                 if( $n === false || $n > $sourceBase ) {
2912                         return false;
2913                 }
2914                 $inDigits[] = $n;
2915         }
2916
2917         // Iterate over the input, modulo-ing out an output digit
2918         // at a time until input is gone.
2919         while( count( $inDigits ) ) {
2920                 $work = 0;
2921                 $workDigits = array();
2922
2923                 // Long division...
2924                 foreach( $inDigits as $digit ) {
2925                         $work *= $sourceBase;
2926                         $work += $digit;
2927
2928                         if( $work < $destBase ) {
2929                                 // Gonna need to pull another digit.
2930                                 if( count( $workDigits ) ) {
2931                                         // Avoid zero-padding; this lets us find
2932                                         // the end of the input very easily when
2933                                         // length drops to zero.
2934                                         $workDigits[] = 0;
2935                                 }
2936                         } else {
2937                                 // Finally! Actual division!
2938                                 $workDigits[] = intval( $work / $destBase );
2939
2940                                 // Isn't it annoying that most programming languages
2941                                 // don't have a single divide-and-remainder operator,
2942                                 // even though the CPU implements it that way?
2943                                 $work = $work % $destBase;
2944                         }
2945                 }
2946
2947                 // All that division leaves us with a remainder,
2948                 // which is conveniently our next output digit.
2949                 $outChars .= $digitChars[$work];
2950
2951                 // And we continue!
2952                 $inDigits = $workDigits;
2953         }
2954
2955         while( strlen( $outChars ) < $pad ) {
2956                 $outChars .= '0';
2957         }
2958
2959         return strrev( $outChars );
2960 }
2961
2962 /**
2963  * Create an object with a given name and an array of construct parameters
2964  * @param $name String
2965  * @param $p Array: parameters
2966  */
2967 function wfCreateObject( $name, $p ) {
2968         $p = array_values( $p );
2969         switch ( count( $p ) ) {
2970                 case 0:
2971                         return new $name;
2972                 case 1:
2973                         return new $name( $p[0] );
2974                 case 2:
2975                         return new $name( $p[0], $p[1] );
2976                 case 3:
2977                         return new $name( $p[0], $p[1], $p[2] );
2978                 case 4:
2979                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2980                 case 5:
2981                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2982                 case 6:
2983                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2984                 default:
2985                         throw new MWException( 'Too many arguments to construtor in wfCreateObject' );
2986         }
2987 }
2988
2989 function wfHttpOnlySafe() {
2990         global $wgHttpOnlyBlacklist;
2991         if( !version_compare( '5.2', PHP_VERSION, '<' ) ) {
2992                 return false;
2993         }
2994
2995         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2996                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2997                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2998                                 return false;
2999                         }
3000                 }
3001         }
3002
3003         return true;
3004 }
3005
3006 /**
3007  * Initialise php session
3008  */
3009 function wfSetupSession( $sessionId = false ) {
3010         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3011                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3012         if( $wgSessionsInMemcached ) {
3013                 require_once( 'MemcachedSessions.php' );
3014         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3015                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3016                 # hasn't already been set to the desired value (that causes errors)
3017                 ini_set( 'session.save_handler', $wgSessionHandler );
3018         }
3019         $httpOnlySafe = wfHttpOnlySafe();
3020         wfDebugLog( 'cookie',
3021                 'session_set_cookie_params: "' . implode( '", "',
3022                         array(
3023                                 0,
3024                                 $wgCookiePath,
3025                                 $wgCookieDomain,
3026                                 $wgCookieSecure,
3027                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
3028         if( $httpOnlySafe && $wgCookieHttpOnly ) {
3029                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
3030         } else {
3031                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
3032                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
3033         }
3034         session_cache_limiter( 'private, must-revalidate' );
3035         if ( $sessionId ) {
3036                 session_id( $sessionId );
3037         }
3038         wfSuppressWarnings();
3039         session_start();
3040         wfRestoreWarnings();
3041 }
3042
3043 /**
3044  * Get an object from the precompiled serialized directory
3045  *
3046  * @return Mixed: the variable on success, false on failure
3047  */
3048 function wfGetPrecompiledData( $name ) {
3049         global $IP;
3050
3051         $file = "$IP/serialized/$name";
3052         if ( file_exists( $file ) ) {
3053                 $blob = file_get_contents( $file );
3054                 if ( $blob ) {
3055                         return unserialize( $blob );
3056                 }
3057         }
3058         return false;
3059 }
3060
3061 function wfGetCaller( $level = 2 ) {
3062         $backtrace = wfDebugBacktrace();
3063         if ( isset( $backtrace[$level] ) ) {
3064                 return wfFormatStackFrame( $backtrace[$level] );
3065         } else {
3066                 $caller = 'unknown';
3067         }
3068         return $caller;
3069 }
3070
3071 /**
3072  * Return a string consisting of callers in the stack. Useful sometimes
3073  * for profiling specific points.
3074  *
3075  * @param $limit The maximum depth of the stack frame to return, or false for
3076  *               the entire stack.
3077  */
3078 function wfGetAllCallers( $limit = 3 ) {
3079         $trace = array_reverse( wfDebugBacktrace() );
3080         if ( !$limit || $limit > count( $trace ) - 1 ) {
3081                 $limit = count( $trace ) - 1;
3082         }
3083         $trace = array_slice( $trace, -$limit - 1, $limit );
3084         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
3085 }
3086
3087 /**
3088  * Return a string representation of frame
3089  */
3090 function wfFormatStackFrame( $frame ) {
3091         return isset( $frame['class'] ) ?
3092                 $frame['class'] . '::' . $frame['function'] :
3093                 $frame['function'];
3094 }
3095
3096 /**
3097  * Get a cache key
3098  */
3099 function wfMemcKey( /*... */ ) {
3100         $args = func_get_args();
3101         $key = wfWikiID() . ':' . implode( ':', $args );
3102         $key = str_replace( ' ', '_', $key );
3103         return $key;
3104 }
3105
3106 /**
3107  * Get a cache key for a foreign DB
3108  */
3109 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3110         $args = array_slice( func_get_args(), 2 );
3111         if ( $prefix ) {
3112                 $key = "$db-$prefix:" . implode( ':', $args );
3113         } else {
3114                 $key = $db . ':' . implode( ':', $args );
3115         }
3116         return $key;
3117 }
3118
3119 /**
3120  * Get an ASCII string identifying this wiki
3121  * This is used as a prefix in memcached keys
3122  */
3123 function wfWikiID() {
3124         global $wgDBprefix, $wgDBname;
3125         if ( $wgDBprefix ) {
3126                 return "$wgDBname-$wgDBprefix";
3127         } else {
3128                 return $wgDBname;
3129         }
3130 }
3131
3132 /**
3133  * Split a wiki ID into DB name and table prefix
3134  */
3135 function wfSplitWikiID( $wiki ) {
3136         $bits = explode( '-', $wiki, 2 );
3137         if ( count( $bits ) < 2 ) {
3138                 $bits[] = '';
3139         }
3140         return $bits;
3141 }
3142
3143 /**
3144  * Get a Database object.
3145  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3146  *            master (for write queries), DB_SLAVE for potentially lagged read
3147  *            queries, or an integer >= 0 for a particular server.
3148  *
3149  * @param $groups Mixed: query groups. An array of group names that this query
3150  *                belongs to. May contain a single string if the query is only
3151  *                in one group.
3152  *
3153  * @param $wiki String: the wiki ID, or false for the current wiki
3154  *
3155  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3156  * will always return the same object, unless the underlying connection or load
3157  * balancer is manually destroyed.
3158  *
3159  * @return DatabaseBase
3160  */
3161 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3162         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3163 }
3164
3165 /**
3166  * Get a load balancer object.
3167  *
3168  * @param $wiki String: wiki ID, or false for the current wiki
3169  * @return LoadBalancer
3170  */
3171 function wfGetLB( $wiki = false ) {
3172         return wfGetLBFactory()->getMainLB( $wiki );
3173 }
3174
3175 /**
3176  * Get the load balancer factory object
3177  * @return LBFactory
3178  */
3179 function &wfGetLBFactory() {
3180         return LBFactory::singleton();
3181 }
3182
3183 /**
3184  * Find a file.
3185  * Shortcut for RepoGroup::singleton()->findFile()
3186  * @param $title String or Title object
3187  * @param $options Associative array of options:
3188  *     time:           requested time for an archived image, or false for the
3189  *                     current version. An image object will be returned which was
3190  *                     created at the specified time.
3191  *
3192  *     ignoreRedirect: If true, do not follow file redirects
3193  *
3194  *     private:        If true, return restricted (deleted) files if the current
3195  *                     user is allowed to view them. Otherwise, such files will not
3196  *                     be found.
3197  *
3198  *     bypassCache:    If true, do not use the process-local cache of File objects
3199  *
3200  * @return File, or false if the file does not exist
3201  */
3202 function wfFindFile( $title, $options = array() ) {
3203         return RepoGroup::singleton()->findFile( $title, $options );
3204 }
3205
3206 /**
3207  * Get an object referring to a locally registered file.
3208  * Returns a valid placeholder object if the file does not exist.
3209  * @param $title Title or String
3210  * @return File, or null if passed an invalid Title
3211  */
3212 function wfLocalFile( $title ) {
3213         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3214 }
3215
3216 /**
3217  * Should low-performance queries be disabled?
3218  *
3219  * @return Boolean
3220  */
3221 function wfQueriesMustScale() {
3222         global $wgMiserMode;
3223         return $wgMiserMode
3224                 || ( SiteStats::pages() > 100000
3225                 && SiteStats::edits() > 1000000
3226                 && SiteStats::users() > 10000 );
3227 }
3228
3229 /**
3230  * Get the path to a specified script file, respecting file
3231  * extensions; this is a wrapper around $wgScriptExtension etc.
3232  *
3233  * @param $script String: script filename, sans extension
3234  * @return String
3235  */
3236 function wfScript( $script = 'index' ) {
3237         global $wgScriptPath, $wgScriptExtension;
3238         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3239 }
3240
3241 /**
3242  * Get the script URL.
3243  *
3244  * @return script URL
3245  */
3246 function wfGetScriptUrl() {
3247         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3248                 #
3249                 # as it was called, minus the query string.
3250                 #
3251                 # Some sites use Apache rewrite rules to handle subdomains,
3252                 # and have PHP set up in a weird way that causes PHP_SELF
3253                 # to contain the rewritten URL instead of the one that the
3254                 # outside world sees.
3255                 #
3256                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3257                 # provides containing the "before" URL.
3258                 return $_SERVER['SCRIPT_NAME'];
3259         } else {
3260                 return $_SERVER['URL'];
3261         }
3262 }
3263
3264 /**
3265  * Convenience function converts boolean values into "true"
3266  * or "false" (string) values
3267  *
3268  * @param $value Boolean
3269  * @return String
3270  */
3271 function wfBoolToStr( $value ) {
3272         return $value ? 'true' : 'false';
3273 }
3274
3275 /**
3276  * Load an extension messages file
3277  * @deprecated in 1.16, warnings in 1.18, remove in 1.20
3278  */
3279 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
3280         wfDeprecated( __FUNCTION__ );
3281 }
3282
3283 /**
3284  * Get a platform-independent path to the null file, e.g.
3285  * /dev/null
3286  *
3287  * @return string
3288  */
3289 function wfGetNull() {
3290         return wfIsWindows()
3291                 ? 'NUL'
3292                 : '/dev/null';
3293 }
3294
3295 /**
3296  * Displays a maxlag error
3297  *
3298  * @param $host String: server that lags the most
3299  * @param $lag Integer: maxlag (actual)
3300  * @param $maxLag Integer: maxlag (requested)
3301  */
3302 function wfMaxlagError( $host, $lag, $maxLag ) {
3303         global $wgShowHostnames;
3304         header( 'HTTP/1.1 503 Service Unavailable' );
3305         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
3306         header( 'X-Database-Lag: ' . intval( $lag ) );
3307         header( 'Content-Type: text/plain' );
3308         if( $wgShowHostnames ) {
3309                 echo "Waiting for $host: $lag seconds lagged\n";
3310         } else {
3311                 echo "Waiting for a database server: $lag seconds lagged\n";
3312         }
3313 }
3314
3315 /**
3316  * Throws a warning that $function is deprecated
3317  * @param $function String
3318  * @return null
3319  */
3320 function wfDeprecated( $function ) {
3321         static $functionsWarned = array();
3322         if ( !isset( $functionsWarned[$function] ) ) {
3323                 $functionsWarned[$function] = true;
3324                 wfWarn( "Use of $function is deprecated.", 2 );
3325         }
3326 }
3327
3328 /**
3329  * Send a warning either to the debug log or in a PHP error depending on
3330  * $wgDevelopmentWarnings
3331  *
3332  * @param $msg String: message to send
3333  * @param $callerOffset Integer: number of itmes to go back in the backtrace to
3334  *        find the correct caller (1 = function calling wfWarn, ...)
3335  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3336  *        is true
3337  */
3338 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3339         $callers = wfDebugBacktrace();
3340         if( isset( $callers[$callerOffset + 1] ) ){
3341                 $callerfunc = $callers[$callerOffset + 1];
3342                 $callerfile = $callers[$callerOffset];
3343                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3344                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3345                 } else {
3346                         $file = '(internal function)';
3347                 }
3348                 $func = '';
3349                 if( isset( $callerfunc['class'] ) ) {
3350                         $func .= $callerfunc['class'] . '::';
3351                 }
3352                 if( isset( $callerfunc['function'] ) ) {
3353                         $func .= $callerfunc['function'];
3354                 }
3355                 $msg .= " [Called from $func in $file]";
3356         }
3357
3358         global $wgDevelopmentWarnings;
3359         if ( $wgDevelopmentWarnings ) {
3360                 trigger_error( $msg, $level );
3361         } else {
3362                 wfDebug( "$msg\n" );
3363         }
3364 }
3365
3366 /**
3367  * Sleep until the worst slave's replication lag is less than or equal to
3368  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
3369  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3370  * a no-op if there are no slaves.
3371  *
3372  * Every time the function has to wait for a slave, it will print a message to
3373  * that effect (and then sleep for a little while), so it's probably not best
3374  * to use this outside maintenance scripts in its present form.
3375  *
3376  * @param $maxLag Integer
3377  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3378  * @return null
3379  */
3380 function wfWaitForSlaves( $maxLag, $wiki = false ) {
3381         if( $maxLag ) {
3382                 $lb = wfGetLB( $wiki );
3383                 list( $host, $lag ) = $lb->getMaxLag( $wiki );
3384                 while( $lag > $maxLag ) {
3385                         wfSuppressWarnings();
3386                         $name = gethostbyaddr( $host );
3387                         wfRestoreWarnings();
3388                         if( $name !== false ) {
3389                                 $host = $name;
3390                         }
3391                         print "Waiting for $host (lagged $lag seconds)...\n";
3392                         sleep( $maxLag );
3393                         list( $host, $lag ) = $lb->getMaxLag();
3394                 }
3395         }
3396 }
3397
3398 /**
3399  * Used to be used for outputting text in the installer/updater
3400  * @deprecated Warnings in 1.19, removal in 1.20
3401  */
3402 function wfOut( $s ) {
3403         global $wgCommandLineMode;
3404         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3405                 echo $s;
3406         } else {
3407                 echo htmlspecialchars( $s );
3408         }
3409         flush();
3410 }
3411
3412 /**
3413  * Count down from $n to zero on the terminal, with a one-second pause
3414  * between showing each number. For use in command-line scripts.
3415  */
3416 function wfCountDown( $n ) {
3417         for ( $i = $n; $i >= 0; $i-- ) {
3418                 if ( $i != $n ) {
3419                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3420                 }
3421                 echo $i;
3422                 flush();
3423                 if ( $i ) {
3424                         sleep( 1 );
3425                 }
3426         }
3427         echo "\n";
3428 }
3429
3430 /**
3431  * Generate a random 32-character hexadecimal token.
3432  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3433  *              characters before hashing.
3434  */
3435 function wfGenerateToken( $salt = '' ) {
3436         $salt = serialize( $salt );
3437         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3438 }
3439
3440 /**
3441  * Replace all invalid characters with -
3442  * @param $name Mixed: filename to process
3443  */
3444 function wfStripIllegalFilenameChars( $name ) {
3445         global $wgIllegalFileChars;
3446         $name = wfBaseName( $name );
3447         $name = preg_replace(
3448                 "/[^" . Title::legalChars() . "]" .
3449                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3450                         "/",
3451                 '-',
3452                 $name
3453         );
3454         return $name;
3455 }
3456
3457 /**
3458  * Insert array into another array after the specified *KEY*
3459  * @param $array Array: The array.
3460  * @param $insert Array: The array to insert.
3461  * @param $after Mixed: The key to insert after
3462  */
3463 function wfArrayInsertAfter( $array, $insert, $after ) {
3464         // Find the offset of the element to insert after.
3465         $keys = array_keys( $array );
3466         $offsetByKey = array_flip( $keys );
3467
3468         $offset = $offsetByKey[$after];
3469
3470         // Insert at the specified offset
3471         $before = array_slice( $array, 0, $offset + 1, true );
3472         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
3473
3474         $output = $before + $insert + $after;
3475
3476         return $output;
3477 }
3478
3479 /* Recursively converts the parameter (an object) to an array with the same data */
3480 function wfObjectToArray( $object, $recursive = true ) {
3481         $array = array();
3482         foreach ( get_object_vars( $object ) as $key => $value ) {
3483                 if ( is_object( $value ) && $recursive ) {
3484                         $value = wfObjectToArray( $value );
3485                 }
3486
3487                 $array[$key] = $value;
3488         }
3489
3490         return $array;
3491 }
3492
3493 /**
3494  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3495  * @return Integer value memory was set to.
3496  */
3497 function wfMemoryLimit() {
3498         global $wgMemoryLimit;
3499         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3500         if( $memlimit != -1 ) {
3501                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3502                 if( $conflimit == -1 ) {
3503                         wfDebug( "Removing PHP's memory limit\n" );
3504                         wfSuppressWarnings();
3505                         ini_set( 'memory_limit', $conflimit );
3506                         wfRestoreWarnings();
3507                         return $conflimit;
3508                 } elseif ( $conflimit > $memlimit ) {
3509                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3510                         wfSuppressWarnings();
3511                         ini_set( 'memory_limit', $conflimit );
3512                         wfRestoreWarnings();
3513                         return $conflimit;
3514                 }
3515         }
3516         return $memlimit;
3517 }
3518
3519 /**
3520  * Converts shorthand byte notation to integer form
3521  * @param $string String
3522  * @return Integer
3523  */
3524 function wfShorthandToInteger( $string = '' ) {
3525         $string = trim( $string );
3526         if( $string === '' ) {
3527                 return -1;
3528         }
3529         $last = $string[strlen( $string ) - 1];
3530         $val = intval( $string );
3531         switch( $last ) {
3532                 case 'g':
3533                 case 'G':
3534                         $val *= 1024;
3535                         // break intentionally missing
3536                 case 'm':
3537                 case 'M':
3538                         $val *= 1024;
3539                         // break intentionally missing
3540                 case 'k':
3541                 case 'K':
3542                         $val *= 1024;
3543         }
3544
3545         return $val;
3546 }
3547
3548 /**
3549  * Get the normalised IETF language tag
3550  * @param $code String: The language code.
3551  * @return $langCode String: The language code which complying with BCP 47 standards.
3552  */
3553 function wfBCP47( $code ) {
3554         $codeSegment = explode( '-', $code );
3555         foreach ( $codeSegment as $segNo => $seg ) {
3556                 if ( count( $codeSegment ) > 0 ) {
3557                         // ISO 3166 country code
3558                         if ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3559                                 $codeBCP[$segNo] = strtoupper( $seg );
3560                         // ISO 15924 script code
3561                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3562                                 $codeBCP[$segNo] = ucfirst( $seg );
3563                         // Use lowercase for other cases
3564                         } else {
3565                                 $codeBCP[$segNo] = strtolower( $seg );
3566                         }
3567                 } else {
3568                 // Use lowercase for single segment
3569                         $codeBCP[$segNo] = strtolower( $seg );
3570                 }
3571         }
3572         $langCode = implode( '-', $codeBCP );
3573         return $langCode;
3574 }
3575
3576 function wfArrayMap( $function, $input ) {
3577         $ret = array_map( $function, $input );
3578         foreach ( $ret as $key => $value ) {
3579                 $taint = istainted( $input[$key] );
3580                 if ( $taint ) {
3581                         taint( $ret[$key], $taint );
3582                 }
3583         }
3584         return $ret;
3585 }