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