includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 require_once dirname( __FILE__ ) . '/normal/UtfNormalUtil.php';
  12
  13 // Hide compatibility functions from Doxygen
  14 /// @cond
  15
  16 /**
  17  * Compatibility functions
  18  *
  19  * We more or less support PHP 5.0.x and up.
  20  * Re-implementations of newer functions or functions in non-standard
  21  * PHP extensions may be included here.
  22  */
  23 if( !function_exists( 'iconv' ) ) {
  24         # iconv support is not in the default configuration and so may not be present.
  25         # Assume will only ever use utf-8 and iso-8859-1.
  26         # This will *not* work in all circumstances.
  27         function iconv( $from, $to, $string ) {
  28                 if ( substr( $to, -8 ) == '//IGNORE' ) {
  29                         $to = substr( $to, 0, strlen( $to ) - 8 );
  30                 }
  31                 if( strcasecmp( $from, $to ) == 0 ) {
  32                         return $string;
  33                 }
  34                 if( strcasecmp( $from, 'utf-8' ) == 0 ) {
  35                         return utf8_decode( $string );
  36                 }
  37                 if( strcasecmp( $to, 'utf-8' ) == 0 ) {
  38                         return utf8_encode( $string );
  39                 }
  40                 return $string;
  41         }
  42 }
  43
  44 if ( !function_exists( 'mb_substr' ) ) {
  45         /**
  46          * Fallback implementation for mb_substr, hardcoded to UTF-8.
  47          * Attempts to be at least _moderately_ efficient; best optimized
  48          * for relatively small offset and count values -- about 5x slower
  49          * than native mb_string in my testing.
  50          *
  51          * Larger offsets are still fairly efficient for Latin text, but
  52          * can be up to 100x slower than native if the text is heavily
  53          * multibyte and we have to slog through a few hundred kb.
  54          */
  55         function mb_substr( $str, $start, $count='end' ) {
  56                 if( $start != 0 ) {
  57                         $split = mb_substr_split_unicode( $str, intval( $start ) );
  58                         $str = substr( $str, $split );
  59                 }
  60
  61                 if( $count !== 'end' ) {
  62                         $split = mb_substr_split_unicode( $str, intval( $count ) );
  63                         $str = substr( $str, 0, $split );
  64                 }
  65
  66                 return $str;
  67         }
  68
  69         function mb_substr_split_unicode( $str, $splitPos ) {
  70                 if( $splitPos == 0 ) {
  71                         return 0;
  72                 }
  73
  74                 $byteLen = strlen( $str );
  75
  76                 if( $splitPos > 0 ) {
  77                         if( $splitPos > 256 ) {
  78                                 // Optimize large string offsets by skipping ahead N bytes.
  79                                 // This will cut out most of our slow time on Latin-based text,
  80                                 // and 1/2 to 1/3 on East European and Asian scripts.
  81                                 $bytePos = $splitPos;
  82                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  83                                         ++$bytePos;
  84                                 }
  85                                 $charPos = mb_strlen( substr( $str, 0, $bytePos ) );
  86                         } else {
  87                                 $charPos = 0;
  88                                 $bytePos = 0;
  89                         }
  90
  91                         while( $charPos++ < $splitPos ) {
  92                                 ++$bytePos;
  93                                 // Move past any tail bytes
  94                                 while ( $bytePos < $byteLen && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
  95                                         ++$bytePos;
  96                                 }
  97                         }
  98                 } else {
  99                         $splitPosX = $splitPos + 1;
 100                         $charPos = 0; // relative to end of string; we don't care about the actual char position here
 101                         $bytePos = $byteLen;
 102                         while( $bytePos > 0 && $charPos-- >= $splitPosX ) {
 103                                 --$bytePos;
 104                                 // Move past any tail bytes
 105                                 while ( $bytePos > 0 && $str{$bytePos} >= "\x80" && $str{$bytePos} < "\xc0" ) {
 106                                         --$bytePos;
 107                                 }
 108                         }
 109                 }
 110
 111                 return $bytePos;
 112         }
 113 }
 114
 115 if ( !function_exists( 'mb_strlen' ) ) {
 116         /**
 117          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
 118          * @param string $str
 119          * @param string $enc optional encoding; ignored
 120          * @return int
 121          */
 122         function mb_strlen( $str, $enc = '' ) {
 123                 $counts = count_chars( $str );
 124                 $total = 0;
 125
 126                 // Count ASCII bytes
 127                 for( $i = 0; $i < 0x80; $i++ ) {
 128                         $total += $counts[$i];
 129                 }
 130
 131                 // Count multibyte sequence heads
 132                 for( $i = 0xc0; $i < 0xff; $i++ ) {
 133                         $total += $counts[$i];
 134                 }
 135                 return $total;
 136         }
 137 }
 138
 139
 140 if( !function_exists( 'mb_strpos' ) ) {
 141         /**
 142          * Fallback implementation of mb_strpos, hardcoded to UTF-8.
 143          * @param $haystack String
 144          * @param $needle String
 145          * @param $offset String: optional start position
 146          * @param $encoding String: optional encoding; ignored
 147          * @return int
 148          */
 149         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 150                 $needle = preg_quote( $needle, '/' );
 151
 152                 $ar = array();
 153                 preg_match( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 154
 155                 if( isset( $ar[0][1] ) ) {
 156                         return $ar[0][1];
 157                 } else {
 158                         return false;
 159                 }
 160         }
 161 }
 162
 163 if( !function_exists( 'mb_strrpos' ) ) {
 164         /**
 165          * Fallback implementation of mb_strrpos, hardcoded to UTF-8.
 166          * @param $haystack String
 167          * @param $needle String
 168          * @param $offset String: optional start position
 169          * @param $encoding String: optional encoding; ignored
 170          * @return int
 171          */
 172         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
 173                 $needle = preg_quote( $needle, '/' );
 174
 175                 $ar = array();
 176                 preg_match_all( '/' . $needle . '/u', $haystack, $ar, PREG_OFFSET_CAPTURE, $offset );
 177
 178                 if( isset( $ar[0] ) && count( $ar[0] ) > 0 &&
 179                         isset( $ar[0][count( $ar[0] ) - 1][1] ) ) {
 180                         return $ar[0][count( $ar[0] ) - 1][1];
 181                 } else {
 182                         return false;
 183                 }
 184         }
 185 }
 186
 187 // Support for Wietse Venema's taint feature
 188 if ( !function_exists( 'istainted' ) ) {
 189         function istainted( $var ) {
 190                 return 0;
 191         }
 192         function taint( $var, $level = 0 ) {}
 193         function untaint( $var, $level = 0 ) {}
 194         define( 'TC_HTML', 1 );
 195         define( 'TC_SHELL', 1 );
 196         define( 'TC_MYSQL', 1 );
 197         define( 'TC_PCRE', 1 );
 198         define( 'TC_SELF', 1 );
 199 }
 200 /// @endcond
 201
 202
 203 /**
 204  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 205  */
 206 function wfArrayDiff2( $a, $b ) {
 207         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 208 }
 209 function wfArrayDiff2_cmp( $a, $b ) {
 210         if ( !is_array( $a ) ) {
 211                 return strcmp( $a, $b );
 212         } elseif ( count( $a ) !== count( $b ) ) {
 213                 return count( $a ) < count( $b ) ? -1 : 1;
 214         } else {
 215                 reset( $a );
 216                 reset( $b );
 217                 while( ( list( $keyA, $valueA ) = each( $a ) ) && ( list( $keyB, $valueB ) = each( $b ) ) ) {
 218                         $cmp = strcmp( $valueA, $valueB );
 219                         if ( $cmp !== 0 ) {
 220                                 return $cmp;
 221                         }
 222                 }
 223                 return 0;
 224         }
 225 }
 226
 227 /**
 228  * Seed Mersenne Twister
 229  * No-op for compatibility; only necessary in PHP < 4.2.0
 230  * @deprecated. Remove in 1.18
 231  */
 232 function wfSeedRandom() {
 233         wfDeprecated(__FUNCTION__);
 234 }
 235
 236 /**
 237  * Get a random decimal value between 0 and 1, in a way
 238  * not likely to give duplicate values for any realistic
 239  * number of articles.
 240  *
 241  * @return string
 242  */
 243 function wfRandom() {
 244         # The maximum random value is "only" 2^31-1, so get two random
 245         # values to reduce the chance of dupes
 246         $max = mt_getrandmax() + 1;
 247         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 248                 / $max / $max, 12, '.', '' );
 249         return $rand;
 250 }
 251
 252 /**
 253  * We want some things to be included as literal characters in our title URLs
 254  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 255  * all of the following should be safe:
 256  *
 257  * ;:@&=$-_.+!*'(),
 258  *
 259  * But + is not safe because it's used to indicate a space; &= are only safe in
 260  * paths and not in queries (and we don't distinguish here); ' seems kind of
 261  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 262  * is reserved, we don't care.  So the list we unescape is:
 263  *
 264  * ;:@$!*(),/
 265  *
 266  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 267  * so no fancy : for IIS7.
 268  *
 269  * %2F in the page titles seems to fatally break for some reason.
 270  *
 271  * @param $s String:
 272  * @return string
 273 */
 274 function wfUrlencode( $s ) {
 275         static $needle;
 276         if ( is_null( $needle ) ) {
 277                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 278                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 279                         $needle[] = '%3A';
 280                 }
 281         }
 282
 283         $s = urlencode( $s );
 284         $s = str_ireplace(
 285                 $needle,
 286                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 287                 $s
 288         );
 289
 290         return $s;
 291 }
 292
 293 /**
 294  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 295  * In normal operation this is a NOP.
 296  *
 297  * Controlling globals:
 298  * $wgDebugLogFile - points to the log file
 299  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 300  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 301  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 302  *
 303  * @param $text String
 304  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 305  */
 306 function wfDebug( $text, $logonly = false ) {
 307         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 308         global $wgDebugLogPrefix, $wgShowDebug;
 309         static $recursion = 0;
 310
 311         static $cache = array(); // Cache of unoutputted messages
 312         $text = wfDebugTimer() . $text;
 313
 314         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 315         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 316                 return;
 317         }
 318
 319         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 320                 $cache[] = $text;
 321
 322                 if ( !isset( $wgOut ) ) {
 323                         return;
 324                 }
 325                 if ( !StubObject::isRealObject( $wgOut ) ) {
 326                         if ( $recursion ) {
 327                                 return;
 328                         }
 329                         $recursion++;
 330                         $wgOut->_unstub();
 331                         $recursion--;
 332                 }
 333
 334                 // add the message and possible cached ones to the output
 335                 array_map( array( $wgOut, 'debug' ), $cache );
 336                 $cache = array();
 337         }
 338         if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 339                 # Strip unprintables; they can switch terminal modes when binary data
 340                 # gets dumped, which is pretty annoying.
 341                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 342                 $text = $wgDebugLogPrefix . $text;
 343                 wfErrorLog( $text, $wgDebugLogFile );
 344         }
 345 }
 346
 347 function wfDebugTimer() {
 348         global $wgDebugTimestamps;
 349         if ( !$wgDebugTimestamps ) {
 350                 return '';
 351         }
 352         static $start = null;
 353
 354         if ( $start === null ) {
 355                 $start = microtime( true );
 356                 $prefix = "\n$start";
 357         } else {
 358                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 359         }
 360
 361         return $prefix . '  ';
 362 }
 363
 364 /**
 365  * Send a line giving PHP memory usage.
 366  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 367  */
 368 function wfDebugMem( $exact = false ) {
 369         $mem = memory_get_usage();
 370         if( !$exact ) {
 371                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 372         } else {
 373                 $mem .= ' bytes';
 374         }
 375         wfDebug( "Memory usage: $mem\n" );
 376 }
 377
 378 /**
 379  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 380  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 381  *
 382  * @param $logGroup String
 383  * @param $text String
 384  * @param $public Bool: whether to log the event in the public log if no private
 385  *                     log file is specified, (default true)
 386  */
 387 function wfDebugLog( $logGroup, $text, $public = true ) {
 388         global $wgDebugLogGroups, $wgShowHostnames;
 389         $text = trim( $text ) . "\n";
 390         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 391                 $time = wfTimestamp( TS_DB );
 392                 $wiki = wfWikiID();
 393                 if ( $wgShowHostnames ) {
 394                         $host = wfHostname();
 395                 } else {
 396                         $host = '';
 397                 }
 398                 wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 399         } elseif ( $public === true ) {
 400                 wfDebug( $text, true );
 401         }
 402 }
 403
 404 /**
 405  * Log for database errors
 406  * @param $text String: database error message.
 407  */
 408 function wfLogDBError( $text ) {
 409         global $wgDBerrorLog, $wgDBname;
 410         if ( $wgDBerrorLog ) {
 411                 $host = trim(`hostname`);
 412                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 413                 wfErrorLog( $text, $wgDBerrorLog );
 414         }
 415 }
 416
 417 /**
 418  * Log to a file without getting "file size exceeded" signals.
 419  *
 420  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 421  * send lines to the specified port, prefixed by the specified prefix and a space.
 422  */
 423 function wfErrorLog( $text, $file ) {
 424         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 425                 # Needs the sockets extension
 426                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 427                         // IPv6 bracketed host
 428                         $protocol = $m[1];
 429                         $host = $m[2];
 430                         $port = intval( $m[3] );
 431                         $prefix = isset( $m[4] ) ? $m[4] : false;
 432                         $domain = AF_INET6;
 433                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 434                         $protocol = $m[1];
 435                         $host = $m[2];
 436                         if ( !IP::isIPv4( $host ) ) {
 437                                 $host = gethostbyname( $host );
 438                         }
 439                         $port = intval( $m[3] );
 440                         $prefix = isset( $m[4] ) ? $m[4] : false;
 441                         $domain = AF_INET;
 442                 } else {
 443                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 444                 }
 445                 // Clean it up for the multiplexer
 446                 if ( strval( $prefix ) !== '' ) {
 447                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 448                         if ( substr( $text, -1 ) != "\n" ) {
 449                                 $text .= "\n";
 450                         }
 451                 }
 452
 453                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 454                 if ( !$sock ) {
 455                         return;
 456                 }
 457                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 458                 socket_close( $sock );
 459         } else {
 460                 wfSuppressWarnings();
 461                 $exists = file_exists( $file );
 462                 $size = $exists ? filesize( $file ) : false;
 463                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 464                         error_log( $text, 3, $file );
 465                 }
 466                 wfRestoreWarnings();
 467         }
 468 }
 469
 470 /**
 471  * @todo document
 472  */
 473 function wfLogProfilingData() {
 474         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 475         global $wgProfiler, $wgProfileLimit, $wgUser;
 476         # Profiling must actually be enabled...
 477         if( is_null( $wgProfiler ) ) {
 478                 return;
 479         }
 480         # Get total page request time
 481         $now = wfTime();
 482         $elapsed = $now - $wgRequestTime;
 483         # Only show pages that longer than $wgProfileLimit time (default is 0)
 484         if( $elapsed <= $wgProfileLimit ) {
 485                 return;
 486         }
 487         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 488         $forward = '';
 489         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 490                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 491         }
 492         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 493                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 494         }
 495         if( !empty( $_SERVER['HTTP_FROM'] ) ) {
 496                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 497         }
 498         if( $forward ) {
 499                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 500         }
 501         // Don't unstub $wgUser at this late stage just for statistics purposes
 502         if( StubObject::isRealObject( $wgUser ) && $wgUser->isAnon() ) {
 503                 $forward .= ' anon';
 504         }
 505         $log = sprintf( "%s\t%04.3f\t%s\n",
 506                 gmdate( 'YmdHis' ), $elapsed,
 507                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 508         if ( $wgDebugLogFile != '' && ( $wgRequest->getVal( 'action' ) != 'raw' || $wgDebugRawPage ) ) {
 509                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 510         }
 511 }
 512
 513 /**
 514  * Check if the wiki read-only lock file is present. This can be used to lock
 515  * off editing functions, but doesn't guarantee that the database will not be
 516  * modified.
 517  * @return bool
 518  */
 519 function wfReadOnly() {
 520         global $wgReadOnlyFile, $wgReadOnly;
 521
 522         if ( !is_null( $wgReadOnly ) ) {
 523                 return (bool)$wgReadOnly;
 524         }
 525         if ( $wgReadOnlyFile == '' ) {
 526                 return false;
 527         }
 528         // Set $wgReadOnly for faster access next time
 529         if ( is_file( $wgReadOnlyFile ) ) {
 530                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 531         } else {
 532                 $wgReadOnly = false;
 533         }
 534         return (bool)$wgReadOnly;
 535 }
 536
 537 function wfReadOnlyReason() {
 538         global $wgReadOnly;
 539         wfReadOnly();
 540         return $wgReadOnly;
 541 }
 542
 543 /**
 544  * Return a Language object from $langcode
 545  * @param $langcode Mixed: either:
 546  *                  - a Language object
 547  *                  - code of the language to get the message for, if it is
 548  *                    a valid code create a language for that language, if
 549  *                    it is a string but not a valid code then make a basic
 550  *                    language object
 551  *                  - a boolean: if it's false then use the current users
 552  *                    language (as a fallback for the old parameter
 553  *                    functionality), or if it is true then use the wikis
 554  * @return Language object
 555  */
 556 function wfGetLangObj( $langcode = false ) {
 557         # Identify which language to get or create a language object for.
 558         # Using is_object here due to Stub objects.
 559         if( is_object( $langcode ) ) {
 560                 # Great, we already have the object (hopefully)!
 561                 return $langcode;
 562         }
 563
 564         global $wgContLang, $wgLanguageCode;
 565         if( $langcode === true || $langcode === $wgLanguageCode ) {
 566                 # $langcode is the language code of the wikis content language object.
 567                 # or it is a boolean and value is true
 568                 return $wgContLang;
 569         }
 570
 571         global $wgLang;
 572         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 573                 # $langcode is the language code of user language object.
 574                 # or it was a boolean and value is false
 575                 return $wgLang;
 576         }
 577
 578         $validCodes = array_keys( Language::getLanguageNames() );
 579         if( in_array( $langcode, $validCodes ) ) {
 580                 # $langcode corresponds to a valid language.
 581                 return Language::factory( $langcode );
 582         }
 583
 584         # $langcode is a string, but not a valid language code; use content language.
 585         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 586         return $wgContLang;
 587 }
 588
 589 /**
 590  * Use this instead of $wgContLang, when working with user interface.
 591  * User interface is currently hard coded according to wiki content language
 592  * in many ways, especially regarding to text direction. There is lots stuff
 593  * to fix, hence this function to keep the old behaviour unless the global
 594  * $wgBetterDirectionality is enabled (or removed when everything works).
 595  */
 596 function wfUILang() {
 597         global $wgBetterDirectionality;
 598         return wfGetLangObj( !$wgBetterDirectionality );
 599 }
 600
 601 /**
 602  * This is the new function for getting translated interface messages.
 603  * See the Message class for documentation how to use them.
 604  * The intention is that this function replaces all old wfMsg* functions.
 605  * @param $key \string Message key.
 606  * Varargs: normal message parameters.
 607  * @return \type{Message}
 608  * @since 1.17
 609  */
 610 function wfMessage( $key /*...*/) {
 611         $params = func_get_args();
 612         array_shift( $params );
 613         return new Message( $key, $params );
 614 }
 615
 616 /**
 617  * Get a message from anywhere, for the current user language.
 618  *
 619  * Use wfMsgForContent() instead if the message should NOT
 620  * change depending on the user preferences.
 621  *
 622  * @param $key String: lookup key for the message, usually
 623  *    defined in languages/Language.php
 624  *
 625  * This function also takes extra optional parameters (not
 626  * shown in the function definition), which can be used to
 627  * insert variable text into the predefined message.
 628  */
 629 function wfMsg( $key ) {
 630         $args = func_get_args();
 631         array_shift( $args );
 632         return wfMsgReal( $key, $args, true );
 633 }
 634
 635 /**
 636  * Same as above except doesn't transform the message
 637  */
 638 function wfMsgNoTrans( $key ) {
 639         $args = func_get_args();
 640         array_shift( $args );
 641         return wfMsgReal( $key, $args, true, false, false );
 642 }
 643
 644 /**
 645  * Get a message from anywhere, for the current global language
 646  * set with $wgLanguageCode.
 647  *
 648  * Use this if the message should NOT change dependent on the
 649  * language set in the user's preferences. This is the case for
 650  * most text written into logs, as well as link targets (such as
 651  * the name of the copyright policy page). Link titles, on the
 652  * other hand, should be shown in the UI language.
 653  *
 654  * Note that MediaWiki allows users to change the user interface
 655  * language in their preferences, but a single installation
 656  * typically only contains content in one language.
 657  *
 658  * Be wary of this distinction: If you use wfMsg() where you should
 659  * use wfMsgForContent(), a user of the software may have to
 660  * customize potentially hundreds of messages in
 661  * order to, e.g., fix a link in every possible language.
 662  *
 663  * @param $key String: lookup key for the message, usually
 664  *    defined in languages/Language.php
 665  */
 666 function wfMsgForContent( $key ) {
 667         global $wgForceUIMsgAsContentMsg;
 668         $args = func_get_args();
 669         array_shift( $args );
 670         $forcontent = true;
 671         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 672                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 673         {
 674                 $forcontent = false;
 675         }
 676         return wfMsgReal( $key, $args, true, $forcontent );
 677 }
 678
 679 /**
 680  * Same as above except doesn't transform the message
 681  */
 682 function wfMsgForContentNoTrans( $key ) {
 683         global $wgForceUIMsgAsContentMsg;
 684         $args = func_get_args();
 685         array_shift( $args );
 686         $forcontent = true;
 687         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 688                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 689         {
 690                 $forcontent = false;
 691         }
 692         return wfMsgReal( $key, $args, true, $forcontent, false );
 693 }
 694
 695 /**
 696  * Get a message from the language file, for the UI elements
 697  */
 698 function wfMsgNoDB( $key ) {
 699         $args = func_get_args();
 700         array_shift( $args );
 701         return wfMsgReal( $key, $args, false );
 702 }
 703
 704 /**
 705  * Get a message from the language file, for the content
 706  */
 707 function wfMsgNoDBForContent( $key ) {
 708         global $wgForceUIMsgAsContentMsg;
 709         $args = func_get_args();
 710         array_shift( $args );
 711         $forcontent = true;
 712         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 713                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 714         {
 715                 $forcontent = false;
 716         }
 717         return wfMsgReal( $key, $args, false, $forcontent );
 718 }
 719
 720
 721 /**
 722  * Really get a message
 723  * @param $key String: key to get.
 724  * @param $args
 725  * @param $useDB Boolean
 726  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
 727  * @param $transform Boolean: Whether or not to transform the message.
 728  * @return String: the requested message.
 729  */
 730 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
 731         wfProfileIn( __METHOD__ );
 732         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 733         $message = wfMsgReplaceArgs( $message, $args );
 734         wfProfileOut( __METHOD__ );
 735         return $message;
 736 }
 737
 738 /**
 739  * This function provides the message source for messages to be edited which are *not* stored in the database.
 740  * @param $key String:
 741  */
 742 function wfMsgWeirdKey( $key ) {
 743         $source = wfMsgGetKey( $key, false, true, false );
 744         if ( wfEmptyMsg( $key, $source ) ) {
 745                 return '';
 746         } else {
 747                 return $source;
 748         }
 749 }
 750
 751 /**
 752  * Fetch a message string value, but don't replace any keys yet.
 753  * @param $key String
 754  * @param $useDB Bool
 755  * @param $langCode String: Code of the language to get the message for, or
 756  *                  behaves as a content language switch if it is a boolean.
 757  * @param $transform Boolean: whether to parse magic words, etc.
 758  * @return string
 759  */
 760 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 761         global $wgMessageCache;
 762
 763         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
 764
 765         if ( !is_object( $wgMessageCache ) ) {
 766                 throw new MWException( 'Trying to get message before message cache is initialised' );
 767         }
 768
 769         $message = $wgMessageCache->get( $key, $useDB, $langCode );
 770         if( $message === false ) {
 771                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
 772         } elseif ( $transform ) {
 773                 $message = $wgMessageCache->transform( $message );
 774         }
 775         return $message;
 776 }
 777
 778 /**
 779  * Replace message parameter keys on the given formatted output.
 780  *
 781  * @param $message String
 782  * @param $args Array
 783  * @return string
 784  * @private
 785  */
 786 function wfMsgReplaceArgs( $message, $args ) {
 787         # Fix windows line-endings
 788         # Some messages are split with explode("\n", $msg)
 789         $message = str_replace( "\r", '', $message );
 790
 791         // Replace arguments
 792         if ( count( $args ) ) {
 793                 if ( is_array( $args[0] ) ) {
 794                         $args = array_values( $args[0] );
 795                 }
 796                 $replacementKeys = array();
 797                 foreach( $args as $n => $param ) {
 798                         $replacementKeys['$' . ( $n + 1 )] = $param;
 799                 }
 800                 $message = strtr( $message, $replacementKeys );
 801         }
 802
 803         return $message;
 804 }
 805
 806 /**
 807  * Return an HTML-escaped version of a message.
 808  * Parameter replacements, if any, are done *after* the HTML-escaping,
 809  * so parameters may contain HTML (eg links or form controls). Be sure
 810  * to pre-escape them if you really do want plaintext, or just wrap
 811  * the whole thing in htmlspecialchars().
 812  *
 813  * @param $key String
 814  * @param string ... parameters
 815  * @return string
 816  */
 817 function wfMsgHtml( $key ) {
 818         $args = func_get_args();
 819         array_shift( $args );
 820         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 821 }
 822
 823 /**
 824  * Return an HTML version of message
 825  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 826  * so parameters may contain HTML (eg links or form controls). Be sure
 827  * to pre-escape them if you really do want plaintext, or just wrap
 828  * the whole thing in htmlspecialchars().
 829  *
 830  * @param $key String
 831  * @param string ... parameters
 832  * @return string
 833  */
 834 function wfMsgWikiHtml( $key ) {
 835         global $wgOut;
 836         $args = func_get_args();
 837         array_shift( $args );
 838         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 839 }
 840
 841 /**
 842  * Returns message in the requested format
 843  * @param $key String: key of the message
 844  * @param $options Array: processing rules. Can take the following options:
 845  *   <i>parse</i>: parses wikitext to HTML
 846  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
 847  *       p's added by parser or tidy
 848  *   <i>escape</i>: filters message through htmlspecialchars
 849  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
 850  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
 851  *   <i>parsemag</i>: transform the message using magic phrases
 852  *   <i>content</i>: fetch message for content language instead of interface
 853  * Also can accept a single associative argument, of the form 'language' => 'xx':
 854  *   <i>language</i>: Language object or language code to fetch message for
 855  *       (overriden by <i>content</i>), its behaviour with parser, parseinline
 856  *       and parsemag is undefined.
 857  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 858  */
 859 function wfMsgExt( $key, $options ) {
 860         global $wgOut;
 861
 862         $args = func_get_args();
 863         array_shift( $args );
 864         array_shift( $args );
 865         $options = (array)$options;
 866
 867         foreach( $options as $arrayKey => $option ) {
 868                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
 869                         # An unknown index, neither numeric nor "language"
 870                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
 871                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
 872                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
 873                 'replaceafter', 'parsemag', 'content' ) ) ) {
 874                         # A numeric index with unknown value
 875                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
 876                 }
 877         }
 878
 879         if( in_array( 'content', $options, true ) ) {
 880                 $forContent = true;
 881                 $langCode = true;
 882         } elseif( array_key_exists( 'language', $options ) ) {
 883                 $forContent = false;
 884                 $langCode = wfGetLangObj( $options['language'] );
 885         } else {
 886                 $forContent = false;
 887                 $langCode = false;
 888         }
 889
 890         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 891
 892         if( !in_array( 'replaceafter', $options, true ) ) {
 893                 $string = wfMsgReplaceArgs( $string, $args );
 894         }
 895
 896         if( in_array( 'parse', $options, true ) ) {
 897                 $string = $wgOut->parse( $string, true, !$forContent );
 898         } elseif ( in_array( 'parseinline', $options, true ) ) {
 899                 $string = $wgOut->parse( $string, true, !$forContent );
 900                 $m = array();
 901                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 902                         $string = $m[1];
 903                 }
 904         } elseif ( in_array( 'parsemag', $options, true ) ) {
 905                 global $wgMessageCache;
 906                 if ( isset( $wgMessageCache ) ) {
 907                         $string = $wgMessageCache->transform( $string,
 908                                 !$forContent,
 909                                 is_object( $langCode ) ? $langCode : null );
 910                 }
 911         }
 912
 913         if ( in_array( 'escape', $options, true ) ) {
 914                 $string = htmlspecialchars ( $string );
 915         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
 916                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 917         }
 918
 919         if( in_array( 'replaceafter', $options, true ) ) {
 920                 $string = wfMsgReplaceArgs( $string, $args );
 921         }
 922
 923         return $string;
 924 }
 925
 926
 927 /**
 928  * Just like exit() but makes a note of it.
 929  * Commits open transactions except if the error parameter is set
 930  *
 931  * @deprecated Please return control to the caller or throw an exception
 932  */
 933 function wfAbruptExit( $error = false ) {
 934         static $called = false;
 935         if ( $called ) {
 936                 exit( -1 );
 937         }
 938         $called = true;
 939
 940         $bt = wfDebugBacktrace();
 941         if( $bt ) {
 942                 for( $i = 0; $i < count( $bt ); $i++ ) {
 943                         $file = isset( $bt[$i]['file'] ) ? $bt[$i]['file'] : 'unknown';
 944                         $line = isset( $bt[$i]['line'] ) ? $bt[$i]['line'] : 'unknown';
 945                         wfDebug( "WARNING: Abrupt exit in $file at line $line\n");
 946                 }
 947         } else {
 948                 wfDebug( "WARNING: Abrupt exit\n" );
 949         }
 950
 951         wfLogProfilingData();
 952
 953         if ( !$error ) {
 954                 wfGetLB()->closeAll();
 955         }
 956         exit( -1 );
 957 }
 958
 959 /**
 960  * @deprecated Please return control the caller or throw an exception
 961  */
 962 function wfErrorExit() {
 963         wfAbruptExit( true );
 964 }
 965
 966 /**
 967  * Print a simple message and die, returning nonzero to the shell if any.
 968  * Plain die() fails to return nonzero to the shell if you pass a string.
 969  * @param $msg String
 970  */
 971 function wfDie( $msg = '' ) {
 972         echo $msg;
 973         die( 1 );
 974 }
 975
 976 /**
 977  * Throw a debugging exception. This function previously once exited the process,
 978  * but now throws an exception instead, with similar results.
 979  *
 980  * @param $msg String: message shown when dieing.
 981  */
 982 function wfDebugDieBacktrace( $msg = '' ) {
 983         throw new MWException( $msg );
 984 }
 985
 986 /**
 987  * Fetch server name for use in error reporting etc.
 988  * Use real server name if available, so we know which machine
 989  * in a server farm generated the current page.
 990  * @return string
 991  */
 992 function wfHostname() {
 993         static $host;
 994         if ( is_null( $host ) ) {
 995                 if ( function_exists( 'posix_uname' ) ) {
 996                         // This function not present on Windows
 997                         $uname = @posix_uname();
 998                 } else {
 999                         $uname = false;
1000                 }
1001                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1002                         $host = $uname['nodename'];
1003                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1004                         # Windows computer name
1005                         $host = getenv( 'COMPUTERNAME' );
1006                 } else {
1007                         # This may be a virtual server.
1008                         $host = $_SERVER['SERVER_NAME'];
1009                 }
1010         }
1011         return $host;
1012 }
1013
1014 /**
1015  * Returns a HTML comment with the elapsed time since request.
1016  * This method has no side effects.
1017  * @return string
1018  */
1019 function wfReportTime() {
1020         global $wgRequestTime, $wgShowHostnames;
1021
1022         $now = wfTime();
1023         $elapsed = $now - $wgRequestTime;
1024
1025         return $wgShowHostnames
1026                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1027                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1028 }
1029
1030 /**
1031  * Safety wrapper for debug_backtrace().
1032  *
1033  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1034  * murky circumstances, which may be triggered in part by stub objects
1035  * or other fancy talkin'.
1036  *
1037  * Will return an empty array if Zend Optimizer is detected or if
1038  * debug_backtrace is disabled, otherwise the output from
1039  * debug_backtrace() (trimmed).
1040  *
1041  * @return array of backtrace information
1042  */
1043 function wfDebugBacktrace() {
1044         static $disabled = null;
1045
1046         if( extension_loaded( 'Zend Optimizer' ) ) {
1047                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1048                 return array();
1049         }
1050
1051         if ( is_null( $disabled ) ) {
1052                 $disabled = false;
1053                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1054                 $functions = array_map( 'trim', $functions );
1055                 $functions = array_map( 'strtolower', $functions );
1056                 if ( in_array( 'debug_backtrace', $functions ) ) {
1057                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1058                         $disabled = true;
1059                 }
1060         }
1061         if ( $disabled ) {
1062                 return array();
1063         }
1064
1065         return array_slice( debug_backtrace(), 1 );
1066 }
1067
1068 function wfBacktrace() {
1069         global $wgCommandLineMode;
1070
1071         if ( $wgCommandLineMode ) {
1072                 $msg = '';
1073         } else {
1074                 $msg = "<ul>\n";
1075         }
1076         $backtrace = wfDebugBacktrace();
1077         foreach( $backtrace as $call ) {
1078                 if( isset( $call['file'] ) ) {
1079                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1080                         $file = $f[count( $f ) - 1];
1081                 } else {
1082                         $file = '-';
1083                 }
1084                 if( isset( $call['line'] ) ) {
1085                         $line = $call['line'];
1086                 } else {
1087                         $line = '-';
1088                 }
1089                 if ( $wgCommandLineMode ) {
1090                         $msg .= "$file line $line calls ";
1091                 } else {
1092                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1093                 }
1094                 if( !empty( $call['class'] ) ) {
1095                         $msg .= $call['class'] . '::';
1096                 }
1097                 $msg .= $call['function'] . '()';
1098
1099                 if ( $wgCommandLineMode ) {
1100                         $msg .= "\n";
1101                 } else {
1102                         $msg .= "</li>\n";
1103                 }
1104         }
1105         if ( $wgCommandLineMode ) {
1106                 $msg .= "\n";
1107         } else {
1108                 $msg .= "</ul>\n";
1109         }
1110
1111         return $msg;
1112 }
1113
1114
1115 /* Some generic result counters, pulled out of SearchEngine */
1116
1117
1118 /**
1119  * @todo document
1120  */
1121 function wfShowingResults( $offset, $limit ) {
1122         global $wgLang;
1123         return wfMsgExt(
1124                 'showingresults',
1125                 array( 'parseinline' ),
1126                 $wgLang->formatNum( $limit ),
1127                 $wgLang->formatNum( $offset + 1 )
1128         );
1129 }
1130
1131 /**
1132  * @todo document
1133  */
1134 function wfShowingResultsNum( $offset, $limit, $num ) {
1135         global $wgLang;
1136         return wfMsgExt(
1137                 'showingresultsnum',
1138                 array( 'parseinline' ),
1139                 $wgLang->formatNum( $limit ),
1140                 $wgLang->formatNum( $offset + 1 ),
1141                 $wgLang->formatNum( $num )
1142         );
1143 }
1144
1145 /**
1146  * Generate (prev x| next x) (20|50|100...) type links for paging
1147  * @param $offset String
1148  * @param $limit Integer
1149  * @param $link String
1150  * @param $query String: optional URL query parameter string
1151  * @param $atend Bool: optional param for specified if this is the last page
1152  */
1153 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1154         global $wgLang;
1155         $fmtLimit = $wgLang->formatNum( $limit );
1156         // FIXME: Why on earth this needs one message for the text and another one for tooltip??
1157         # Get prev/next link display text
1158         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1159         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1160         # Get prev/next link title text
1161         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1162         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1163         # Fetch the title object
1164         if( is_object( $link ) ) {
1165                 $title =& $link;
1166         } else {
1167                 $title = Title::newFromText( $link );
1168                 if( is_null( $title ) ) {
1169                         return false;
1170                 }
1171         }
1172         # Make 'previous' link
1173         if( 0 != $offset ) {
1174                 $po = $offset - $limit;
1175                 $po = max( $po, 0 );
1176                 $q = "limit={$limit}&offset={$po}";
1177                 if( $query != '' ) {
1178                         $q .= '&' . $query;
1179                 }
1180                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1181         } else {
1182                 $plink = $prev;
1183         }
1184         # Make 'next' link
1185         $no = $offset + $limit;
1186         $q = "limit={$limit}&offset={$no}";
1187         if( $query != '' ) {
1188                 $q .= '&' . $query;
1189         }
1190         if( $atend ) {
1191                 $nlink = $next;
1192         } else {
1193                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1194         }
1195         # Make links to set number of items per page
1196         $nums = $wgLang->pipeList( array(
1197                 wfNumLink( $offset, 20, $title, $query ),
1198                 wfNumLink( $offset, 50, $title, $query ),
1199                 wfNumLink( $offset, 100, $title, $query ),
1200                 wfNumLink( $offset, 250, $title, $query ),
1201                 wfNumLink( $offset, 500, $title, $query )
1202         ) );
1203         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1204 }
1205
1206 /**
1207  * Generate links for (20|50|100...) items-per-page links
1208  * @param $offset String
1209  * @param $limit Integer
1210  * @param $title Title
1211  * @param $query String: optional URL query parameter string
1212  */
1213 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1214         global $wgLang;
1215         if( $query == '' ) {
1216                 $q = '';
1217         } else {
1218                 $q = $query.'&';
1219         }
1220         $q .= "limit={$limit}&offset={$offset}";
1221         $fmtLimit = $wgLang->formatNum( $limit );
1222         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1223         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1224         return $s;
1225 }
1226
1227 /**
1228  * @todo document
1229  * @todo FIXME: we may want to blacklist some broken browsers
1230  *
1231  * @return bool Whereas client accept gzip compression
1232  */
1233 function wfClientAcceptsGzip() {
1234         if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1235                 # FIXME: we may want to blacklist some broken browsers
1236                 $m = array();
1237                 if( preg_match(
1238                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1239                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1240                         $m )
1241                 )
1242                 {
1243                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1244                                 return false;
1245                         }
1246                         wfDebug( " accepts gzip\n" );
1247                         return true;
1248                 }
1249         }
1250         return false;
1251 }
1252
1253 /**
1254  * Obtain the offset and limit values from the request string;
1255  * used in special pages
1256  *
1257  * @param $deflimit Default limit if none supplied
1258  * @param $optionname Name of a user preference to check against
1259  * @return array
1260  *
1261  */
1262 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1263         global $wgRequest;
1264         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1265 }
1266
1267 /**
1268  * Escapes the given text so that it may be output using addWikiText()
1269  * without any linking, formatting, etc. making its way through. This
1270  * is achieved by substituting certain characters with HTML entities.
1271  * As required by the callers, <nowiki> is not used. It currently does
1272  * not filter out characters which have special meaning only at the
1273  * start of a line, such as "*".
1274  *
1275  * @param $text String: text to be escaped
1276  */
1277 function wfEscapeWikiText( $text ) {
1278         $text = str_replace(
1279                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ), # }}
1280                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
1281                 htmlspecialchars( $text )
1282         );
1283         return $text;
1284 }
1285
1286 /**
1287  * @todo document
1288  */
1289 function wfQuotedPrintable( $string, $charset = '' ) {
1290         # Probably incomplete; see RFC 2045
1291         if( empty( $charset ) ) {
1292                 global $wgInputEncoding;
1293                 $charset = $wgInputEncoding;
1294         }
1295         $charset = strtoupper( $charset );
1296         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
1297
1298         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
1299         $replace = $illegal . '\t ?_';
1300         if( !preg_match( "/[$illegal]/", $string ) ) {
1301                 return $string;
1302         }
1303         $out = "=?$charset?Q?";
1304         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
1305         $out .= '?=';
1306         return $out;
1307 }
1308
1309
1310 /**
1311  * @todo document
1312  * @return float
1313  */
1314 function wfTime() {
1315         return microtime( true );
1316 }
1317
1318 /**
1319  * Sets dest to source and returns the original value of dest
1320  * If source is NULL, it just returns the value, it doesn't set the variable
1321  */
1322 function wfSetVar( &$dest, $source ) {
1323         $temp = $dest;
1324         if ( !is_null( $source ) ) {
1325                 $dest = $source;
1326         }
1327         return $temp;
1328 }
1329
1330 /**
1331  * As for wfSetVar except setting a bit
1332  */
1333 function wfSetBit( &$dest, $bit, $state = true ) {
1334         $temp = (bool)( $dest & $bit );
1335         if ( !is_null( $state ) ) {
1336                 if ( $state ) {
1337                         $dest |= $bit;
1338                 } else {
1339                         $dest &= ~$bit;
1340                 }
1341         }
1342         return $temp;
1343 }
1344
1345 /**
1346  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1347  * "days=7&limit=100". Options in the first array override options in the second.
1348  * Options set to "" will not be output.
1349  */
1350 function wfArrayToCGI( $array1, $array2 = null ) {
1351         if ( !is_null( $array2 ) ) {
1352                 $array1 = $array1 + $array2;
1353         }
1354
1355         $cgi = '';
1356         foreach ( $array1 as $key => $value ) {
1357                 if ( $value !== '' ) {
1358                         if ( $cgi != '' ) {
1359                                 $cgi .= '&';
1360                         }
1361                         if ( is_array( $value ) ) {
1362                                 $firstTime = true;
1363                                 foreach ( $value as $v ) {
1364                                         $cgi .= ( $firstTime ? '' : '&') .
1365                                                 urlencode( $key . '[]' ) . '=' .
1366                                                 urlencode( $v );
1367                                         $firstTime = false;
1368                                 }
1369                         } else {
1370                                 if ( is_object( $value ) ) {
1371                                         $value = $value->__toString();
1372                                 }
1373                                 $cgi .= urlencode( $key ) . '=' .
1374                                         urlencode( $value );
1375                         }
1376                 }
1377         }
1378         return $cgi;
1379 }
1380
1381 /**
1382  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1383  * its argument and returns the same string in array form.  This allows compa-
1384  * tibility with legacy functions that accept raw query strings instead of nice
1385  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1386  * valid query strings, or it will explode.
1387  *
1388  * @param $query String: query string
1389  * @return array Array version of input
1390  */
1391 function wfCgiToArray( $query ) {
1392         if( isset( $query[0] ) && $query[0] == '?' ) {
1393                 $query = substr( $query, 1 );
1394         }
1395         $bits = explode( '&', $query );
1396         $ret = array();
1397         foreach( $bits as $bit ) {
1398                 if( $bit === '' ) {
1399                         continue;
1400                 }
1401                 list( $key, $value ) = explode( '=', $bit );
1402                 $key = urldecode( $key );
1403                 $value = urldecode( $value );
1404                 $ret[$key] = $value;
1405         }
1406         return $ret;
1407 }
1408
1409 /**
1410  * Append a query string to an existing URL, which may or may not already
1411  * have query string parameters already. If so, they will be combined.
1412  *
1413  * @param $url String
1414  * @param $query Mixed: string or associative array
1415  * @return string
1416  */
1417 function wfAppendQuery( $url, $query ) {
1418         if ( is_array( $query ) ) {
1419                 $query = wfArrayToCGI( $query );
1420         }
1421         if( $query != '' ) {
1422                 if( false === strpos( $url, '?' ) ) {
1423                         $url .= '?';
1424                 } else {
1425                         $url .= '&';
1426                 }
1427                 $url .= $query;
1428         }
1429         return $url;
1430 }
1431
1432 /**
1433  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
1434  * and $wgProto are correct.
1435  *
1436  * @todo this won't work with current-path-relative URLs
1437  * like "subdir/foo.html", etc.
1438  *
1439  * @param $url String: either fully-qualified or a local path + query
1440  * @return string Fully-qualified URL
1441  */
1442 function wfExpandUrl( $url ) {
1443         if( substr( $url, 0, 2 ) == '//' ) {
1444                 global $wgProto;
1445                 return $wgProto . ':' . $url;
1446         } elseif( substr( $url, 0, 1 ) == '/' ) {
1447                 global $wgServer;
1448                 return $wgServer . $url;
1449         } else {
1450                 return $url;
1451         }
1452 }
1453
1454 /**
1455  * This is obsolete, use SquidUpdate::purge()
1456  * @deprecated
1457  */
1458 function wfPurgeSquidServers( $urlArr ) {
1459         SquidUpdate::purge( $urlArr );
1460 }
1461
1462 /**
1463  * Windows-compatible version of escapeshellarg()
1464  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1465  * function puts single quotes in regardless of OS.
1466  *
1467  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1468  * earlier distro releases of PHP)
1469  */
1470 function wfEscapeShellArg( ) {
1471         wfInitShellLocale();
1472
1473         $args = func_get_args();
1474         $first = true;
1475         $retVal = '';
1476         foreach ( $args as $arg ) {
1477                 if ( !$first ) {
1478                         $retVal .= ' ';
1479                 } else {
1480                         $first = false;
1481                 }
1482
1483                 if ( wfIsWindows() ) {
1484                         // Escaping for an MSVC-style command line parser
1485                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1486                         // Double the backslashes before any double quotes. Escape the double quotes.
1487                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1488                         $arg = '';
1489                         $iteration = 0;
1490                         foreach ( $tokens as $token ) {
1491                                 if ( $iteration % 2 == 1 ) {
1492                                         // Delimiter, a double quote preceded by zero or more slashes
1493                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1494                                 } elseif ( $iteration % 4 == 2 ) {
1495                                         // ^ in $token will be outside quotes, need to be escaped
1496                                         $arg .= str_replace( '^', '^^', $token );
1497                                 } else { // $iteration % 4 == 0
1498                                         // ^ in $token will appear inside double quotes, so leave as is
1499                                         $arg .= $token;
1500                                 }
1501                                 $iteration++;
1502                         }
1503                         // Double the backslashes before the end of the string, because
1504                         // we will soon add a quote
1505                         $m = array();
1506                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1507                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1508                         }
1509
1510                         // Add surrounding quotes
1511                         $retVal .= '"' . $arg . '"';
1512                 } else {
1513                         $retVal .= escapeshellarg( $arg );
1514                 }
1515         }
1516         return $retVal;
1517 }
1518
1519 /**
1520  * wfMerge attempts to merge differences between three texts.
1521  * Returns true for a clean merge and false for failure or a conflict.
1522  */
1523 function wfMerge( $old, $mine, $yours, &$result ) {
1524         global $wgDiff3;
1525
1526         # This check may also protect against code injection in
1527         # case of broken installations.
1528         wfSuppressWarnings();
1529         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1530         wfRestoreWarnings();
1531
1532         if( !$haveDiff3 ) {
1533                 wfDebug( "diff3 not found\n" );
1534                 return false;
1535         }
1536
1537         # Make temporary files
1538         $td = wfTempDir();
1539         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1540         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1541         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1542
1543         fwrite( $oldtextFile, $old );
1544         fclose( $oldtextFile );
1545         fwrite( $mytextFile, $mine );
1546         fclose( $mytextFile );
1547         fwrite( $yourtextFile, $yours );
1548         fclose( $yourtextFile );
1549
1550         # Check for a conflict
1551         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1552                 wfEscapeShellArg( $mytextName ) . ' ' .
1553                 wfEscapeShellArg( $oldtextName ) . ' ' .
1554                 wfEscapeShellArg( $yourtextName );
1555         $handle = popen( $cmd, 'r' );
1556
1557         if( fgets( $handle, 1024 ) ) {
1558                 $conflict = true;
1559         } else {
1560                 $conflict = false;
1561         }
1562         pclose( $handle );
1563
1564         # Merge differences
1565         $cmd = $wgDiff3 . ' -a -e --merge ' .
1566                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1567         $handle = popen( $cmd, 'r' );
1568         $result = '';
1569         do {
1570                 $data = fread( $handle, 8192 );
1571                 if ( strlen( $data ) == 0 ) {
1572                         break;
1573                 }
1574                 $result .= $data;
1575         } while ( true );
1576         pclose( $handle );
1577         unlink( $mytextName );
1578         unlink( $oldtextName );
1579         unlink( $yourtextName );
1580
1581         if ( $result === '' && $old !== '' && !$conflict ) {
1582                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1583                 $conflict = true;
1584         }
1585         return !$conflict;
1586 }
1587
1588 /**
1589  * Returns unified plain-text diff of two texts.
1590  * Useful for machine processing of diffs.
1591  * @param $before String: the text before the changes.
1592  * @param $after String: the text after the changes.
1593  * @param $params String: command-line options for the diff command.
1594  * @return String: unified diff of $before and $after
1595  */
1596 function wfDiff( $before, $after, $params = '-u' ) {
1597         if ( $before == $after ) {
1598                 return '';
1599         }
1600
1601         global $wgDiff;
1602         wfSuppressWarnings();
1603         $haveDiff = $wgDiff && file_exists( $wgDiff );
1604         wfRestoreWarnings();
1605
1606         # This check may also protect against code injection in
1607         # case of broken installations.
1608         if( !$haveDiff ) {
1609                 wfDebug( "diff executable not found\n" );
1610                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1611                 $format = new UnifiedDiffFormatter();
1612                 return $format->format( $diffs );
1613         }
1614
1615         # Make temporary files
1616         $td = wfTempDir();
1617         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1618         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1619
1620         fwrite( $oldtextFile, $before );
1621         fclose( $oldtextFile );
1622         fwrite( $newtextFile, $after );
1623         fclose( $newtextFile );
1624
1625         // Get the diff of the two files
1626         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1627
1628         $h = popen( $cmd, 'r' );
1629
1630         $diff = '';
1631
1632         do {
1633                 $data = fread( $h, 8192 );
1634                 if ( strlen( $data ) == 0 ) {
1635                         break;
1636                 }
1637                 $diff .= $data;
1638         } while ( true );
1639
1640         // Clean up
1641         pclose( $h );
1642         unlink( $oldtextName );
1643         unlink( $newtextName );
1644
1645         // Kill the --- and +++ lines. They're not useful.
1646         $diff_lines = explode( "\n", $diff );
1647         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1648                 unset( $diff_lines[0] );
1649         }
1650         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1651                 unset( $diff_lines[1] );
1652         }
1653
1654         $diff = implode( "\n", $diff_lines );
1655
1656         return $diff;
1657 }
1658
1659 /**
1660  * A wrapper around the PHP function var_export().
1661  * Either print it or add it to the regular output ($wgOut).
1662  *
1663  * @param $var A PHP variable to dump.
1664  */
1665 function wfVarDump( $var ) {
1666         global $wgOut;
1667         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1668         if ( headers_sent() || !@is_object( $wgOut ) ) {
1669                 print $s;
1670         } else {
1671                 $wgOut->addHTML( $s );
1672         }
1673 }
1674
1675 /**
1676  * Provide a simple HTTP error.
1677  */
1678 function wfHttpError( $code, $label, $desc ) {
1679         global $wgOut;
1680         $wgOut->disable();
1681         header( "HTTP/1.0 $code $label" );
1682         header( "Status: $code $label" );
1683         $wgOut->sendCacheControl();
1684
1685         header( 'Content-type: text/html; charset=utf-8' );
1686         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1687                 '<html><head><title>' .
1688                 htmlspecialchars( $label ) .
1689                 '</title></head><body><h1>' .
1690                 htmlspecialchars( $label ) .
1691                 '</h1><p>' .
1692                 nl2br( htmlspecialchars( $desc ) ) .
1693                 "</p></body></html>\n";
1694 }
1695
1696 /**
1697  * Clear away any user-level output buffers, discarding contents.
1698  *
1699  * Suitable for 'starting afresh', for instance when streaming
1700  * relatively large amounts of data without buffering, or wanting to
1701  * output image files without ob_gzhandler's compression.
1702  *
1703  * The optional $resetGzipEncoding parameter controls suppression of
1704  * the Content-Encoding header sent by ob_gzhandler; by default it
1705  * is left. See comments for wfClearOutputBuffers() for why it would
1706  * be used.
1707  *
1708  * Note that some PHP configuration options may add output buffer
1709  * layers which cannot be removed; these are left in place.
1710  *
1711  * @param $resetGzipEncoding Bool
1712  */
1713 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1714         if( $resetGzipEncoding ) {
1715                 // Suppress Content-Encoding and Content-Length
1716                 // headers from 1.10+s wfOutputHandler
1717                 global $wgDisableOutputCompression;
1718                 $wgDisableOutputCompression = true;
1719         }
1720         while( $status = ob_get_status() ) {
1721                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1722                         // Probably from zlib.output_compression or other
1723                         // PHP-internal setting which can't be removed.
1724                         //
1725                         // Give up, and hope the result doesn't break
1726                         // output behavior.
1727                         break;
1728                 }
1729                 if( !ob_end_clean() ) {
1730                         // Could not remove output buffer handler; abort now
1731                         // to avoid getting in some kind of infinite loop.
1732                         break;
1733                 }
1734                 if( $resetGzipEncoding ) {
1735                         if( $status['name'] == 'ob_gzhandler' ) {
1736                                 // Reset the 'Content-Encoding' field set by this handler
1737                                 // so we can start fresh.
1738                                 header( 'Content-Encoding:' );
1739                                 break;
1740                         }
1741                 }
1742         }
1743 }
1744
1745 /**
1746  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1747  *
1748  * Clear away output buffers, but keep the Content-Encoding header
1749  * produced by ob_gzhandler, if any.
1750  *
1751  * This should be used for HTTP 304 responses, where you need to
1752  * preserve the Content-Encoding header of the real result, but
1753  * also need to suppress the output of ob_gzhandler to keep to spec
1754  * and avoid breaking Firefox in rare cases where the headers and
1755  * body are broken over two packets.
1756  */
1757 function wfClearOutputBuffers() {
1758         wfResetOutputBuffers( false );
1759 }
1760
1761 /**
1762  * Converts an Accept-* header into an array mapping string values to quality
1763  * factors
1764  */
1765 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1766         # No arg means accept anything (per HTTP spec)
1767         if( !$accept ) {
1768                 return array( $def => 1.0 );
1769         }
1770
1771         $prefs = array();
1772
1773         $parts = explode( ',', $accept );
1774
1775         foreach( $parts as $part ) {
1776                 # FIXME: doesn't deal with params like 'text/html; level=1'
1777                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1778                 $match = array();
1779                 if( !isset( $qpart ) ) {
1780                         $prefs[$value] = 1.0;
1781                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1782                         $prefs[$value] = floatval( $match[1] );
1783                 }
1784         }
1785
1786         return $prefs;
1787 }
1788
1789 /**
1790  * Checks if a given MIME type matches any of the keys in the given
1791  * array. Basic wildcards are accepted in the array keys.
1792  *
1793  * Returns the matching MIME type (or wildcard) if a match, otherwise
1794  * NULL if no match.
1795  *
1796  * @param $type String
1797  * @param $avail Array
1798  * @return string
1799  * @private
1800  */
1801 function mimeTypeMatch( $type, $avail ) {
1802         if( array_key_exists( $type, $avail ) ) {
1803                 return $type;
1804         } else {
1805                 $parts = explode( '/', $type );
1806                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1807                         return $parts[0] . '/*';
1808                 } elseif( array_key_exists( '*/*', $avail ) ) {
1809                         return '*/*';
1810                 } else {
1811                         return null;
1812                 }
1813         }
1814 }
1815
1816 /**
1817  * Returns the 'best' match between a client's requested internet media types
1818  * and the server's list of available types. Each list should be an associative
1819  * array of type to preference (preference is a float between 0.0 and 1.0).
1820  * Wildcards in the types are acceptable.
1821  *
1822  * @param $cprefs Array: client's acceptable type list
1823  * @param $sprefs Array: server's offered types
1824  * @return string
1825  *
1826  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1827  * XXX: generalize to negotiate other stuff
1828  */
1829 function wfNegotiateType( $cprefs, $sprefs ) {
1830         $combine = array();
1831
1832         foreach( array_keys($sprefs) as $type ) {
1833                 $parts = explode( '/', $type );
1834                 if( $parts[1] != '*' ) {
1835                         $ckey = mimeTypeMatch( $type, $cprefs );
1836                         if( $ckey ) {
1837                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1838                         }
1839                 }
1840         }
1841
1842         foreach( array_keys( $cprefs ) as $type ) {
1843                 $parts = explode( '/', $type );
1844                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1845                         $skey = mimeTypeMatch( $type, $sprefs );
1846                         if( $skey ) {
1847                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1848                         }
1849                 }
1850         }
1851
1852         $bestq = 0;
1853         $besttype = null;
1854
1855         foreach( array_keys( $combine ) as $type ) {
1856                 if( $combine[$type] > $bestq ) {
1857                         $besttype = $type;
1858                         $bestq = $combine[$type];
1859                 }
1860         }
1861
1862         return $besttype;
1863 }
1864
1865 /**
1866  * Array lookup
1867  * Returns an array where the values in the first array are replaced by the
1868  * values in the second array with the corresponding keys
1869  *
1870  * @return array
1871  */
1872 function wfArrayLookup( $a, $b ) {
1873         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1874 }
1875
1876 /**
1877  * Convenience function; returns MediaWiki timestamp for the present time.
1878  * @return string
1879  */
1880 function wfTimestampNow() {
1881         # return NOW
1882         return wfTimestamp( TS_MW, time() );
1883 }
1884
1885 /**
1886  * Reference-counted warning suppression
1887  */
1888 function wfSuppressWarnings( $end = false ) {
1889         static $suppressCount = 0;
1890         static $originalLevel = false;
1891
1892         if ( $end ) {
1893                 if ( $suppressCount ) {
1894                         --$suppressCount;
1895                         if ( !$suppressCount ) {
1896                                 error_reporting( $originalLevel );
1897                         }
1898                 }
1899         } else {
1900                 if ( !$suppressCount ) {
1901                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE ) );
1902                 }
1903                 ++$suppressCount;
1904         }
1905 }
1906
1907 /**
1908  * Restore error level to previous value
1909  */
1910 function wfRestoreWarnings() {
1911         wfSuppressWarnings( true );
1912 }
1913
1914 # Autodetect, convert and provide timestamps of various types
1915
1916 /**
1917  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1918  */
1919 define( 'TS_UNIX', 0 );
1920
1921 /**
1922  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1923  */
1924 define( 'TS_MW', 1 );
1925
1926 /**
1927  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1928  */
1929 define( 'TS_DB', 2 );
1930
1931 /**
1932  * RFC 2822 format, for E-mail and HTTP headers
1933  */
1934 define( 'TS_RFC2822', 3 );
1935
1936 /**
1937  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1938  *
1939  * This is used by Special:Export
1940  */
1941 define( 'TS_ISO_8601', 4 );
1942
1943 /**
1944  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1945  *
1946  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1947  *       DateTime tag and page 36 for the DateTimeOriginal and
1948  *       DateTimeDigitized tags.
1949  */
1950 define( 'TS_EXIF', 5 );
1951
1952 /**
1953  * Oracle format time.
1954  */
1955 define( 'TS_ORACLE', 6 );
1956
1957 /**
1958  * Postgres format time.
1959  */
1960 define( 'TS_POSTGRES', 7 );
1961
1962 /**
1963  * DB2 format time
1964  */
1965 define( 'TS_DB2', 8 );
1966
1967 /**
1968  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
1969  *                    function will autodetect which format is supplied and act
1970  *                    accordingly.
1971  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
1972  * @return String: in the format specified in $outputtype
1973  */
1974 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1975         $uts = 0;
1976         $da = array();
1977         if ( $ts === 0 ) {
1978                 $uts = time();
1979         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1980                 # TS_DB
1981         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
1982                 # TS_EXIF
1983         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
1984                 # TS_MW
1985         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
1986                 # TS_UNIX
1987                 $uts = $ts;
1988         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
1989                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
1990                 $uts = strtotime( preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1991                                 str_replace( '+00:00', 'UTC', $ts ) ) );
1992         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
1993                 # TS_ISO_8601
1994         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
1995                 # TS_POSTGRES
1996         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
1997                 # TS_POSTGRES
1998         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
1999                 # TS_DB2
2000         } elseif ( preg_match( '/^[A-Z][a-z]{2}, \d\d [A-Z][a-z]{2} \d{4} \d\d:\d\d:\d\d/', $ts ) ) {
2001                 # TS_RFC2822
2002                 $uts = strtotime( $ts );
2003         } else {
2004                 # Bogus value; fall back to the epoch...
2005                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2006                 $uts = 0;
2007         }
2008
2009         if (count( $da ) ) {
2010                 // Warning! gmmktime() acts oddly if the month or day is set to 0
2011                 // We may want to handle that explicitly at some point
2012                 $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2013                         (int)$da[2], (int)$da[3], (int)$da[1] );
2014         }
2015
2016         switch( $outputtype ) {
2017                 case TS_UNIX:
2018                         return $uts;
2019                 case TS_MW:
2020                         return gmdate( 'YmdHis', $uts );
2021                 case TS_DB:
2022                         return gmdate( 'Y-m-d H:i:s', $uts );
2023                 case TS_ISO_8601:
2024                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
2025                 // This shouldn't ever be used, but is included for completeness
2026                 case TS_EXIF:
2027                         return gmdate( 'Y:m:d H:i:s', $uts );
2028                 case TS_RFC2822:
2029                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
2030                 case TS_ORACLE:
2031                         return gmdate( 'd-m-Y H:i:s.000000', $uts );
2032                         //return gmdate( 'd-M-y h.i.s A', $uts ) . ' +00:00';
2033                 case TS_POSTGRES:
2034                         return gmdate( 'Y-m-d H:i:s', $uts ) . ' GMT';
2035                 case TS_DB2:
2036                         return gmdate( 'Y-m-d H:i:s', $uts );
2037                 default:
2038                         throw new MWException( 'wfTimestamp() called with illegal output type.' );
2039         }
2040 }
2041
2042 /**
2043  * Return a formatted timestamp, or null if input is null.
2044  * For dealing with nullable timestamp columns in the database.
2045  * @param $outputtype Integer
2046  * @param $ts String
2047  * @return String
2048  */
2049 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2050         if( is_null( $ts ) ) {
2051                 return null;
2052         } else {
2053                 return wfTimestamp( $outputtype, $ts );
2054         }
2055 }
2056
2057 /**
2058  * Check if the operating system is Windows
2059  *
2060  * @return Bool: true if it's Windows, False otherwise.
2061  */
2062 function wfIsWindows() {
2063         if ( substr( php_uname(), 0, 7 ) == 'Windows' ) {
2064                 return true;
2065         } else {
2066                 return false;
2067         }
2068 }
2069
2070 /**
2071  * Swap two variables
2072  */
2073 function swap( &$x, &$y ) {
2074         $z = $x;
2075         $x = $y;
2076         $y = $z;
2077 }
2078
2079 function wfGetCachedNotice( $name ) {
2080         global $wgOut, $wgRenderHashAppend, $parserMemc;
2081         $fname = 'wfGetCachedNotice';
2082         wfProfileIn( $fname );
2083
2084         $needParse = false;
2085
2086         if( $name === 'default' ) {
2087                 // special case
2088                 global $wgSiteNotice;
2089                 $notice = $wgSiteNotice;
2090                 if( empty( $notice ) ) {
2091                         wfProfileOut( $fname );
2092                         return false;
2093                 }
2094         } else {
2095                 $notice = wfMsgForContentNoTrans( $name );
2096                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
2097                         wfProfileOut( $fname );
2098                         return( false );
2099                 }
2100         }
2101
2102         // Use the extra hash appender to let eg SSL variants separately cache.
2103         $key = wfMemcKey( $name . $wgRenderHashAppend );
2104         $cachedNotice = $parserMemc->get( $key );
2105         if( is_array( $cachedNotice ) ) {
2106                 if( md5( $notice ) == $cachedNotice['hash'] ) {
2107                         $notice = $cachedNotice['html'];
2108                 } else {
2109                         $needParse = true;
2110                 }
2111         } else {
2112                 $needParse = true;
2113         }
2114
2115         if( $needParse ) {
2116                 if( is_object( $wgOut ) ) {
2117                         $parsed = $wgOut->parse( $notice );
2118                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
2119                         $notice = $parsed;
2120                 } else {
2121                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' . "\n" );
2122                         $notice = '';
2123                 }
2124         }
2125         $notice = '<div id="localNotice">' .$notice . '</div>';
2126         wfProfileOut( $fname );
2127         return $notice;
2128 }
2129
2130 function wfGetNamespaceNotice() {
2131         global $wgTitle;
2132
2133         # Paranoia
2134         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) ) {
2135                 return '';
2136         }
2137
2138         $fname = 'wfGetNamespaceNotice';
2139         wfProfileIn( $fname );
2140
2141         $key = 'namespacenotice-' . $wgTitle->getNsText();
2142         $namespaceNotice = wfGetCachedNotice( $key );
2143         if ( $namespaceNotice && substr( $namespaceNotice, 0, 7 ) != '<p>&lt;' ) {
2144                 $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . '</div>';
2145         } else {
2146                 $namespaceNotice = '';
2147         }
2148
2149         wfProfileOut( $fname );
2150         return $namespaceNotice;
2151 }
2152
2153 function wfGetSiteNotice() {
2154         global $wgUser;
2155         $fname = 'wfGetSiteNotice';
2156         wfProfileIn( $fname );
2157         $siteNotice = '';
2158
2159         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
2160                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
2161                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
2162                 } else {
2163                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
2164                         if( !$anonNotice ) {
2165                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
2166                         } else {
2167                                 $siteNotice = $anonNotice;
2168                         }
2169                 }
2170                 if( !$siteNotice ) {
2171                         $siteNotice = wfGetCachedNotice( 'default' );
2172                 }
2173         }
2174
2175         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
2176         wfProfileOut( $fname );
2177         return $siteNotice;
2178 }
2179
2180 /**
2181  * BC wrapper for MimeMagic::singleton()
2182  * @deprecated
2183  */
2184 function &wfGetMimeMagic() {
2185         wfDeprecated( __FUNCTION__ );
2186         return MimeMagic::singleton();
2187 }
2188
2189 /**
2190  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2191  * TEMP environment variables are then checked in sequence, and if none are set
2192  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2193  * or C:\Windows\Temp for Windows and hope for the best.
2194  * It is common to call it with tempnam().
2195  *
2196  * NOTE: When possible, use instead the tmpfile() function to create
2197  * temporary files to avoid race conditions on file creation, etc.
2198  *
2199  * @return String
2200  */
2201 function wfTempDir() {
2202         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2203                 $tmp = getenv( $var );
2204                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2205                         return $tmp;
2206                 }
2207         }
2208         if( function_exists( 'sys_get_temp_dir' ) ) {
2209                 return sys_get_temp_dir();
2210         }
2211         # Usual defaults
2212         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2213 }
2214
2215 /**
2216  * Make directory, and make all parent directories if they don't exist
2217  *
2218  * @param $dir String: full path to directory to create
2219  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2220  * @param $caller String: optional caller param for debugging.
2221  * @return bool
2222  */
2223 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2224         global $wgDirectoryMode;
2225
2226         if ( !is_null( $caller ) ) {
2227                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2228         }
2229
2230         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2231                 return true;
2232         }
2233
2234         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2235
2236         if ( is_null( $mode ) ) {
2237                 $mode = $wgDirectoryMode;
2238         }
2239
2240         // Turn off the normal warning, we're doing our own below
2241         wfSuppressWarnings();
2242         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2243         wfRestoreWarnings();
2244
2245         if( !$ok ) {
2246                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2247                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2248         }
2249         return $ok;
2250 }
2251
2252 /**
2253  * Increment a statistics counter
2254  */
2255 function wfIncrStats( $key ) {
2256         global $wgStatsMethod;
2257
2258         if( $wgStatsMethod == 'udp' ) {
2259                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
2260                 static $socket;
2261                 if ( !$socket ) {
2262                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2263                         $statline = "stats/{$wgDBname} - 1 1 1 1 1 -total\n";
2264                         socket_sendto(
2265                                 $socket,
2266                                 $statline,
2267                                 strlen( $statline ),
2268                                 0,
2269                                 $wgUDPProfilerHost,
2270                                 $wgUDPProfilerPort
2271                         );
2272                 }
2273                 $statline = "stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
2274                 @socket_sendto(
2275                         $socket,
2276                         $statline,
2277                         strlen( $statline ),
2278                         0,
2279                         $wgUDPProfilerHost,
2280                         $wgUDPProfilerPort
2281                 );
2282         } elseif( $wgStatsMethod == 'cache' ) {
2283                 global $wgMemc;
2284                 $key = wfMemcKey( 'stats', $key );
2285                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2286                         $wgMemc->add( $key, 1 );
2287                 }
2288         } else {
2289                 // Disabled
2290         }
2291 }
2292
2293 /**
2294  * @param $nr Mixed: the number to format
2295  * @param $acc Integer: the number of digits after the decimal point, default 2
2296  * @param $round Boolean: whether or not to round the value, default true
2297  * @return float
2298  */
2299 function wfPercent( $nr, $acc = 2, $round = true ) {
2300         $ret = sprintf( "%.${acc}f", $nr );
2301         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2302 }
2303
2304 /**
2305  * Encrypt a username/password.
2306  *
2307  * @param $userid Integer: ID of the user
2308  * @param $password String: password of the user
2309  * @return String: hashed password
2310  * @deprecated Use User::crypt() or User::oldCrypt() instead
2311  */
2312 function wfEncryptPassword( $userid, $password ) {
2313         wfDeprecated(__FUNCTION__);
2314         # Just wrap around User::oldCrypt()
2315         return User::oldCrypt( $password, $userid );
2316 }
2317
2318 /**
2319  * Appends to second array if $value differs from that in $default
2320  */
2321 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2322         if ( is_null( $changed ) ) {
2323                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
2324         }
2325         if ( $default[$key] !== $value ) {
2326                 $changed[$key] = $value;
2327         }
2328 }
2329
2330 /**
2331  * Since wfMsg() and co suck, they don't return false if the message key they
2332  * looked up didn't exist but a XHTML string, this function checks for the
2333  * nonexistance of messages by looking at wfMsg() output
2334  *
2335  * @param $key      String: the message key looked up
2336  * @return Boolean True if the message *doesn't* exist.
2337  */
2338 function wfEmptyMsg( $key ) {
2339         global $wgMessageCache;
2340         return $wgMessageCache->get( $key, /*useDB*/true, /*content*/false ) === false;
2341 }
2342
2343 /**
2344  * Find out whether or not a mixed variable exists in a string
2345  *
2346  * @param $needle String
2347  * @param $str String
2348  * @return Boolean
2349  */
2350 function in_string( $needle, $str ) {
2351         return strpos( $str, $needle ) !== false;
2352 }
2353
2354 function wfSpecialList( $page, $details ) {
2355         global $wgContLang;
2356         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : '';
2357         return $page . $details;
2358 }
2359
2360 /**
2361  * Returns a regular expression of url protocols
2362  *
2363  * @return String
2364  */
2365 function wfUrlProtocols() {
2366         global $wgUrlProtocols;
2367
2368         static $retval = null;
2369         if ( !is_null( $retval ) ) {
2370                 return $retval;
2371         }
2372
2373         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2374         // with LocalSettings files from 1.5
2375         if ( is_array( $wgUrlProtocols ) ) {
2376                 $protocols = array();
2377                 foreach ( $wgUrlProtocols as $protocol ) {
2378                         $protocols[] = preg_quote( $protocol, '/' );
2379                 }
2380
2381                 $retval = implode( '|', $protocols );
2382         } else {
2383                 $retval = $wgUrlProtocols;
2384         }
2385         return $retval;
2386 }
2387
2388 /**
2389  * Safety wrapper around ini_get() for boolean settings.
2390  * The values returned from ini_get() are pre-normalized for settings
2391  * set via php.ini or php_flag/php_admin_flag... but *not*
2392  * for those set via php_value/php_admin_value.
2393  *
2394  * It's fairly common for people to use php_value instead of php_flag,
2395  * which can leave you with an 'off' setting giving a false positive
2396  * for code that just takes the ini_get() return value as a boolean.
2397  *
2398  * To make things extra interesting, setting via php_value accepts
2399  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2400  * Unrecognized values go false... again opposite PHP's own coercion
2401  * from string to bool.
2402  *
2403  * Luckily, 'properly' set settings will always come back as '0' or '1',
2404  * so we only have to worry about them and the 'improper' settings.
2405  *
2406  * I frickin' hate PHP... :P
2407  *
2408  * @param $setting String
2409  * @return Bool
2410  */
2411 function wfIniGetBool( $setting ) {
2412         $val = ini_get( $setting );
2413         // 'on' and 'true' can't have whitespace around them, but '1' can.
2414         return strtolower( $val ) == 'on'
2415                 || strtolower( $val ) == 'true'
2416                 || strtolower( $val ) == 'yes'
2417                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2418 }
2419
2420 /**
2421  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2422  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2423  *
2424  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2425  *                          should be omitted
2426  * @return Bool - Whether or not the extension is loaded
2427  */
2428 function wfDl( $extension ) {
2429         if( extension_loaded( $extension ) ) {
2430                 return true;
2431         }
2432
2433         $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2434                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2435
2436         if( $canDl ) {
2437                 wfSuppressWarnings();
2438                 dl( $extension . '.' . PHP_SHLIB_SUFFIX );
2439                 wfRestoreWarnings();
2440         }
2441         return extension_loaded( $extension );
2442 }
2443
2444 /**
2445  * Execute a shell command, with time and memory limits mirrored from the PHP
2446  * configuration if supported.
2447  * @param $cmd Command line, properly escaped for shell.
2448  * @param &$retval optional, will receive the program's exit code.
2449  *                 (non-zero is usually failure)
2450  * @return collected stdout as a string (trailing newlines stripped)
2451  */
2452 function wfShellExec( $cmd, &$retval = null ) {
2453         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2454
2455         static $disabled;
2456         if ( is_null( $disabled ) ) {
2457                 $disabled = false;
2458                 if( wfIniGetBool( 'safe_mode' ) ) {
2459                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2460                         $disabled = true;
2461                 }
2462                 $functions = explode( ',', ini_get( 'disable_functions' ) );
2463                 $functions = array_map( 'trim', $functions );
2464                 $functions = array_map( 'strtolower', $functions );
2465                 if ( in_array( 'passthru', $functions ) ) {
2466                         wfDebug( "passthru is in disabled_functions\n" );
2467                         $disabled = true;
2468                 }
2469         }
2470         if ( $disabled ) {
2471                 $retval = 1;
2472                 return 'Unable to run external programs in safe mode.';
2473         }
2474
2475         wfInitShellLocale();
2476
2477         if ( php_uname( 's' ) == 'Linux' ) {
2478                 $time = intval( $wgMaxShellTime );
2479                 $mem = intval( $wgMaxShellMemory );
2480                 $filesize = intval( $wgMaxShellFileSize );
2481
2482                 if ( $time > 0 && $mem > 0 ) {
2483                         $script = "$IP/bin/ulimit4.sh";
2484                         if ( is_executable( $script ) ) {
2485                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2486                         }
2487                 }
2488         } elseif ( php_uname( 's' ) == 'Windows NT' &&
2489                 version_compare( PHP_VERSION, '5.3.0', '<' ) )
2490         {
2491                 # This is a hack to work around PHP's flawed invocation of cmd.exe
2492                 # http://news.php.net/php.internals/21796
2493                 # Which is fixed in 5.3.0 :)
2494                 $cmd = '"' . $cmd . '"';
2495         }
2496         wfDebug( "wfShellExec: $cmd\n" );
2497
2498         $retval = 1; // error by default?
2499         ob_start();
2500         passthru( $cmd, $retval );
2501         $output = ob_get_contents();
2502         ob_end_clean();
2503
2504         if ( $retval == 127 ) {
2505                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2506         }
2507         return $output;
2508 }
2509
2510 /**
2511  * Workaround for http://bugs.php.net/bug.php?id=45132
2512  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2513  */
2514 function wfInitShellLocale() {
2515         static $done = false;
2516         if ( $done ) {
2517                 return;
2518         }
2519         $done = true;
2520         global $wgShellLocale;
2521         if ( !wfIniGetBool( 'safe_mode' ) ) {
2522                 putenv( "LC_CTYPE=$wgShellLocale" );
2523                 setlocale( LC_CTYPE, $wgShellLocale );
2524         }
2525 }
2526
2527 /**
2528  * This function works like "use VERSION" in Perl, the program will die with a
2529  * backtrace if the current version of PHP is less than the version provided
2530  *
2531  * This is useful for extensions which due to their nature are not kept in sync
2532  * with releases, and might depend on other versions of PHP than the main code
2533  *
2534  * Note: PHP might die due to parsing errors in some cases before it ever
2535  *       manages to call this function, such is life
2536  *
2537  * @see perldoc -f use
2538  *
2539  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2540  *                 a float
2541  */
2542 function wfUsePHP( $req_ver ) {
2543         $php_ver = PHP_VERSION;
2544
2545         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2546                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2547         }
2548 }
2549
2550 /**
2551  * This function works like "use VERSION" in Perl except it checks the version
2552  * of MediaWiki, the program will die with a backtrace if the current version
2553  * of MediaWiki is less than the version provided.
2554  *
2555  * This is useful for extensions which due to their nature are not kept in sync
2556  * with releases
2557  *
2558  * @see perldoc -f use
2559  *
2560  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2561  *                 a float
2562  */
2563 function wfUseMW( $req_ver ) {
2564         global $wgVersion;
2565
2566         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2567                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2568         }
2569 }
2570
2571 /**
2572  * Return the final portion of a pathname.
2573  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2574  * http://bugs.php.net/bug.php?id=33898
2575  *
2576  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2577  * We'll consider it so always, as we don't want \s in our Unix paths either.
2578  *
2579  * @param $path String
2580  * @param $suffix String: to remove if present
2581  * @return String
2582  */
2583 function wfBaseName( $path, $suffix = '' ) {
2584         $encSuffix = ( $suffix == '' )
2585                 ? ''
2586                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2587         $matches = array();
2588         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2589                 return $matches[1];
2590         } else {
2591                 return '';
2592         }
2593 }
2594
2595 /**
2596  * Generate a relative path name to the given file.
2597  * May explode on non-matching case-insensitive paths,
2598  * funky symlinks, etc.
2599  *
2600  * @param $path String: absolute destination path including target filename
2601  * @param $from String: Absolute source path, directory only
2602  * @return String
2603  */
2604 function wfRelativePath( $path, $from ) {
2605         // Normalize mixed input on Windows...
2606         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2607         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2608
2609         // Trim trailing slashes -- fix for drive root
2610         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2611         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2612
2613         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2614         $against = explode( DIRECTORY_SEPARATOR, $from );
2615
2616         if( $pieces[0] !== $against[0] ) {
2617                 // Non-matching Windows drive letters?
2618                 // Return a full path.
2619                 return $path;
2620         }
2621
2622         // Trim off common prefix
2623         while( count( $pieces ) && count( $against )
2624                 && $pieces[0] == $against[0] ) {
2625                 array_shift( $pieces );
2626                 array_shift( $against );
2627         }
2628
2629         // relative dots to bump us to the parent
2630         while( count( $against ) ) {
2631                 array_unshift( $pieces, '..' );
2632                 array_shift( $against );
2633         }
2634
2635         array_push( $pieces, wfBaseName( $path ) );
2636
2637         return implode( DIRECTORY_SEPARATOR, $pieces );
2638 }
2639
2640 /**
2641  * Backwards array plus for people who haven't bothered to read the PHP manual
2642  * XXX: will not darn your socks for you.
2643  *
2644  * @param $array1 Array
2645  * @param [$array2, [...]] Arrays
2646  * @return Array
2647  */
2648 function wfArrayMerge( $array1/* ... */ ) {
2649         $args = func_get_args();
2650         $args = array_reverse( $args, true );
2651         $out = array();
2652         foreach ( $args as $arg ) {
2653                 $out += $arg;
2654         }
2655         return $out;
2656 }
2657
2658 /**
2659  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
2660  * e.g.
2661  *      wfMergeErrorArrays(
2662  *              array( array( 'x' ) ),
2663  *              array( array( 'x', '2' ) ),
2664  *              array( array( 'x' ) ),
2665  *              array( array( 'y') )
2666  *      );
2667  * returns:
2668  *              array(
2669  *              array( 'x', '2' ),
2670  *              array( 'x' ),
2671  *              array( 'y' )
2672  *      )
2673  */
2674 function wfMergeErrorArrays( /*...*/ ) {
2675         $args = func_get_args();
2676         $out = array();
2677         foreach ( $args as $errors ) {
2678                 foreach ( $errors as $params ) {
2679                         # FIXME: sometimes get nested arrays for $params,
2680                         # which leads to E_NOTICEs
2681                         $spec = implode( "\t", $params );
2682                         $out[$spec] = $params;
2683                 }
2684         }
2685         return array_values( $out );
2686 }
2687
2688 /**
2689  * parse_url() work-alike, but non-broken.  Differences:
2690  *
2691  * 1) Does not raise warnings on bad URLs (just returns false)
2692  * 2) Handles protocols that don't use :// (e.g., mailto: and news:) correctly
2693  * 3) Adds a "delimiter" element to the array, either '://' or ':' (see (2))
2694  *
2695  * @param $url String: a URL to parse
2696  * @return Array: bits of the URL in an associative array, per PHP docs
2697  */
2698 function wfParseUrl( $url ) {
2699         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2700         wfSuppressWarnings();
2701         $bits = parse_url( $url );
2702         wfRestoreWarnings();
2703         if ( !$bits ) {
2704                 return false;
2705         }
2706
2707         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2708         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
2709                 $bits['delimiter'] = '://';
2710         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
2711                 $bits['delimiter'] = ':';
2712                 // parse_url detects for news: and mailto: the host part of an url as path
2713                 // We have to correct this wrong detection
2714                 if ( isset( $bits['path'] ) ) {
2715                         $bits['host'] = $bits['path'];
2716                         $bits['path'] = '';
2717                 }
2718         } else {
2719                 return false;
2720         }
2721
2722         return $bits;
2723 }
2724
2725 /**
2726  * Make a URL index, appropriate for the el_index field of externallinks.
2727  */
2728 function wfMakeUrlIndex( $url ) {
2729         $bits = wfParseUrl( $url );
2730
2731         // Reverse the labels in the hostname, convert to lower case
2732         // For emails reverse domainpart only
2733         if ( $bits['scheme'] == 'mailto' ) {
2734                 $mailparts = explode( '@', $bits['host'], 2 );
2735                 if ( count( $mailparts ) === 2 ) {
2736                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2737                 } else {
2738                         // No domain specified, don't mangle it
2739                         $domainpart = '';
2740                 }
2741                 $reversedHost = $domainpart . '@' . $mailparts[0];
2742         } else {
2743                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2744         }
2745         // Add an extra dot to the end
2746         // Why? Is it in wrong place in mailto links?
2747         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2748                 $reversedHost .= '.';
2749         }
2750         // Reconstruct the pseudo-URL
2751         $prot = $bits['scheme'];
2752         $index = $prot . $bits['delimiter'] . $reversedHost;
2753         // Leave out user and password. Add the port, path, query and fragment
2754         if ( isset( $bits['port'] ) ) {
2755                 $index .= ':' . $bits['port'];
2756         }
2757         if ( isset( $bits['path'] ) ) {
2758                 $index .= $bits['path'];
2759         } else {
2760                 $index .= '/';
2761         }
2762         if ( isset( $bits['query'] ) ) {
2763                 $index .= '?' . $bits['query'];
2764         }
2765         if ( isset( $bits['fragment'] ) ) {
2766                 $index .= '#' . $bits['fragment'];
2767         }
2768         return $index;
2769 }
2770
2771 /**
2772  * Do any deferred updates and clear the list
2773  * TODO: This could be in Wiki.php if that class made any sense at all
2774  */
2775 function wfDoUpdates() {
2776         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2777         foreach ( $wgDeferredUpdateList as $update ) {
2778                 $update->doUpdate();
2779         }
2780         foreach ( $wgPostCommitUpdateList as $update ) {
2781                 $update->doUpdate();
2782         }
2783         $wgDeferredUpdateList = array();
2784         $wgPostCommitUpdateList = array();
2785 }
2786
2787 /**
2788  * Convert an arbitrarily-long digit string from one numeric base
2789  * to another, optionally zero-padding to a minimum column width.
2790  *
2791  * Supports base 2 through 36; digit values 10-36 are represented
2792  * as lowercase letters a-z. Input is case-insensitive.
2793  *
2794  * @param $input String: of digits
2795  * @param $sourceBase Integer: 2-36
2796  * @param $destBase Integer: 2-36
2797  * @param $pad Integer: 1 or greater
2798  * @param $lowercase Boolean
2799  * @return String or false on invalid input
2800  */
2801 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2802         $input = strval( $input );
2803         if( $sourceBase < 2 ||
2804                 $sourceBase > 36 ||
2805                 $destBase < 2 ||
2806                 $destBase > 36 ||
2807                 $pad < 1 ||
2808                 $sourceBase != intval( $sourceBase ) ||
2809                 $destBase != intval( $destBase ) ||
2810                 $pad != intval( $pad ) ||
2811                 !is_string( $input ) ||
2812                 $input == '' ) {
2813                 return false;
2814         }
2815         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2816         $inDigits = array();
2817         $outChars = '';
2818
2819         // Decode and validate input string
2820         $input = strtolower( $input );
2821         for( $i = 0; $i < strlen( $input ); $i++ ) {
2822                 $n = strpos( $digitChars, $input{$i} );
2823                 if( $n === false || $n > $sourceBase ) {
2824                         return false;
2825                 }
2826                 $inDigits[] = $n;
2827         }
2828
2829         // Iterate over the input, modulo-ing out an output digit
2830         // at a time until input is gone.
2831         while( count( $inDigits ) ) {
2832                 $work = 0;
2833                 $workDigits = array();
2834
2835                 // Long division...
2836                 foreach( $inDigits as $digit ) {
2837                         $work *= $sourceBase;
2838                         $work += $digit;
2839
2840                         if( $work < $destBase ) {
2841                                 // Gonna need to pull another digit.
2842                                 if( count( $workDigits ) ) {
2843                                         // Avoid zero-padding; this lets us find
2844                                         // the end of the input very easily when
2845                                         // length drops to zero.
2846                                         $workDigits[] = 0;
2847                                 }
2848                         } else {
2849                                 // Finally! Actual division!
2850                                 $workDigits[] = intval( $work / $destBase );
2851
2852                                 // Isn't it annoying that most programming languages
2853                                 // don't have a single divide-and-remainder operator,
2854                                 // even though the CPU implements it that way?
2855                                 $work = $work % $destBase;
2856                         }
2857                 }
2858
2859                 // All that division leaves us with a remainder,
2860                 // which is conveniently our next output digit.
2861                 $outChars .= $digitChars[$work];
2862
2863                 // And we continue!
2864                 $inDigits = $workDigits;
2865         }
2866
2867         while( strlen( $outChars ) < $pad ) {
2868                 $outChars .= '0';
2869         }
2870
2871         return strrev( $outChars );
2872 }
2873
2874 /**
2875  * Create an object with a given name and an array of construct parameters
2876  * @param $name String
2877  * @param $p Array: parameters
2878  */
2879 function wfCreateObject( $name, $p ) {
2880         $p = array_values( $p );
2881         switch ( count( $p ) ) {
2882                 case 0:
2883                         return new $name;
2884                 case 1:
2885                         return new $name( $p[0] );
2886                 case 2:
2887                         return new $name( $p[0], $p[1] );
2888                 case 3:
2889                         return new $name( $p[0], $p[1], $p[2] );
2890                 case 4:
2891                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2892                 case 5:
2893                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2894                 case 6:
2895                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2896                 default:
2897                         throw new MWException( 'Too many arguments to construtor in wfCreateObject' );
2898         }
2899 }
2900
2901 function wfHttpOnlySafe() {
2902         global $wgHttpOnlyBlacklist;
2903         if( !version_compare( '5.2', PHP_VERSION, '<' ) ) {
2904                 return false;
2905         }
2906
2907         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2908                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2909                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2910                                 return false;
2911                         }
2912                 }
2913         }
2914
2915         return true;
2916 }
2917
2918 /**
2919  * Initialise php session
2920  */
2921 function wfSetupSession( $sessionId = false ) {
2922         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
2923                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
2924         if( $wgSessionsInMemcached ) {
2925                 require_once( 'MemcachedSessions.php' );
2926         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
2927                 # Only set this if $wgSessionHandler isn't null and session.save_handler
2928                 # hasn't already been set to the desired value (that causes errors)
2929                 ini_set( 'session.save_handler', $wgSessionHandler );
2930         }
2931         $httpOnlySafe = wfHttpOnlySafe();
2932         wfDebugLog( 'cookie',
2933                 'session_set_cookie_params: "' . implode( '", "',
2934                         array(
2935                                 0,
2936                                 $wgCookiePath,
2937                                 $wgCookieDomain,
2938                                 $wgCookieSecure,
2939                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2940         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2941                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2942         } else {
2943                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2944                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2945         }
2946         session_cache_limiter( 'private, must-revalidate' );
2947         if ( $sessionId ) {
2948                 session_id( $sessionId );
2949         }
2950         wfSuppressWarnings();
2951         session_start();
2952         wfRestoreWarnings();
2953 }
2954
2955 /**
2956  * Get an object from the precompiled serialized directory
2957  *
2958  * @return Mixed: the variable on success, false on failure
2959  */
2960 function wfGetPrecompiledData( $name ) {
2961         global $IP;
2962
2963         $file = "$IP/serialized/$name";
2964         if ( file_exists( $file ) ) {
2965                 $blob = file_get_contents( $file );
2966                 if ( $blob ) {
2967                         return unserialize( $blob );
2968                 }
2969         }
2970         return false;
2971 }
2972
2973 function wfGetCaller( $level = 2 ) {
2974         $backtrace = wfDebugBacktrace();
2975         if ( isset( $backtrace[$level] ) ) {
2976                 return wfFormatStackFrame( $backtrace[$level] );
2977         } else {
2978                 $caller = 'unknown';
2979         }
2980         return $caller;
2981 }
2982
2983 /**
2984  * Return a string consisting of callers in the stack. Useful sometimes
2985  * for profiling specific points.
2986  *
2987  * @param $limit The maximum depth of the stack frame to return, or false for
2988  *               the entire stack.
2989  */
2990 function wfGetAllCallers( $limit = 3 ) {
2991         $trace = array_reverse( wfDebugBacktrace() );
2992         if ( !$limit || $limit > count( $trace ) - 1 ) {
2993                 $limit = count( $trace ) - 1;
2994         }
2995         $trace = array_slice( $trace, -$limit - 1, $limit );
2996         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
2997 }
2998
2999 /**
3000  * Return a string representation of frame
3001  */
3002 function wfFormatStackFrame( $frame ) {
3003         return isset( $frame['class'] ) ?
3004                 $frame['class'] . '::' . $frame['function'] :
3005                 $frame['function'];
3006 }
3007
3008 /**
3009  * Get a cache key
3010  */
3011 function wfMemcKey( /*... */ ) {
3012         $args = func_get_args();
3013         $key = wfWikiID() . ':' . implode( ':', $args );
3014         $key = str_replace( ' ', '_', $key );
3015         return $key;
3016 }
3017
3018 /**
3019  * Get a cache key for a foreign DB
3020  */
3021 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3022         $args = array_slice( func_get_args(), 2 );
3023         if ( $prefix ) {
3024                 $key = "$db-$prefix:" . implode( ':', $args );
3025         } else {
3026                 $key = $db . ':' . implode( ':', $args );
3027         }
3028         return $key;
3029 }
3030
3031 /**
3032  * Get an ASCII string identifying this wiki
3033  * This is used as a prefix in memcached keys
3034  */
3035 function wfWikiID() {
3036         global $wgDBprefix, $wgDBname;
3037         if ( $wgDBprefix ) {
3038                 return "$wgDBname-$wgDBprefix";
3039         } else {
3040                 return $wgDBname;
3041         }
3042 }
3043
3044 /**
3045  * Split a wiki ID into DB name and table prefix
3046  */
3047 function wfSplitWikiID( $wiki ) {
3048         $bits = explode( '-', $wiki, 2 );
3049         if ( count( $bits ) < 2 ) {
3050                 $bits[] = '';
3051         }
3052         return $bits;
3053 }
3054
3055 /**
3056  * Get a Database object.
3057  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3058  *            master (for write queries), DB_SLAVE for potentially lagged read
3059  *            queries, or an integer >= 0 for a particular server.
3060  *
3061  * @param $groups Mixed: query groups. An array of group names that this query
3062  *                belongs to. May contain a single string if the query is only
3063  *                in one group.
3064  *
3065  * @param $wiki String: the wiki ID, or false for the current wiki
3066  *
3067  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3068  * will always return the same object, unless the underlying connection or load
3069  * balancer is manually destroyed.
3070  *
3071  * @return DatabaseBase
3072  */
3073 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3074         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3075 }
3076
3077 /**
3078  * Get a load balancer object.
3079  *
3080  * @param $wiki String: wiki ID, or false for the current wiki
3081  * @return LoadBalancer
3082  */
3083 function wfGetLB( $wiki = false ) {
3084         return wfGetLBFactory()->getMainLB( $wiki );
3085 }
3086
3087 /**
3088  * Get the load balancer factory object
3089  */
3090 function &wfGetLBFactory() {
3091         return LBFactory::singleton();
3092 }
3093
3094 /**
3095  * Find a file.
3096  * Shortcut for RepoGroup::singleton()->findFile()
3097  * @param $title Either a string or Title object
3098  * @param $options Associative array of options:
3099  *     time:           requested time for an archived image, or false for the
3100  *                     current version. An image object will be returned which was
3101  *                     created at the specified time.
3102  *
3103  *     ignoreRedirect: If true, do not follow file redirects
3104  *
3105  *     private:        If true, return restricted (deleted) files if the current
3106  *                     user is allowed to view them. Otherwise, such files will not
3107  *                     be found.
3108  *
3109  *     bypassCache:    If true, do not use the process-local cache of File objects
3110  *
3111  * @return File, or false if the file does not exist
3112  */
3113 function wfFindFile( $title, $options = array() ) {
3114         return RepoGroup::singleton()->findFile( $title, $options );
3115 }
3116
3117 /**
3118  * Get an object referring to a locally registered file.
3119  * Returns a valid placeholder object if the file does not exist.
3120  * @param $title Either a string or Title object
3121  * @return File, or null if passed an invalid Title
3122  */
3123 function wfLocalFile( $title ) {
3124         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3125 }
3126
3127 /**
3128  * Should low-performance queries be disabled?
3129  *
3130  * @return Boolean
3131  */
3132 function wfQueriesMustScale() {
3133         global $wgMiserMode;
3134         return $wgMiserMode
3135                 || ( SiteStats::pages() > 100000
3136                 && SiteStats::edits() > 1000000
3137                 && SiteStats::users() > 10000 );
3138 }
3139
3140 /**
3141  * Get the path to a specified script file, respecting file
3142  * extensions; this is a wrapper around $wgScriptExtension etc.
3143  *
3144  * @param $script String: script filename, sans extension
3145  * @return String
3146  */
3147 function wfScript( $script = 'index' ) {
3148         global $wgScriptPath, $wgScriptExtension;
3149         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3150 }
3151
3152 /**
3153  * Get the script URL.
3154  *
3155  * @return script URL
3156  */
3157 function wfGetScriptUrl() {
3158         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3159                 #
3160                 # as it was called, minus the query string.
3161                 #
3162                 # Some sites use Apache rewrite rules to handle subdomains,
3163                 # and have PHP set up in a weird way that causes PHP_SELF
3164                 # to contain the rewritten URL instead of the one that the
3165                 # outside world sees.
3166                 #
3167                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3168                 # provides containing the "before" URL.
3169                 return $_SERVER['SCRIPT_NAME'];
3170         } else {
3171                 return $_SERVER['URL'];
3172         }
3173 }
3174
3175 /**
3176  * Convenience function converts boolean values into "true"
3177  * or "false" (string) values
3178  *
3179  * @param $value Boolean
3180  * @return String
3181  */
3182 function wfBoolToStr( $value ) {
3183         return $value ? 'true' : 'false';
3184 }
3185
3186 /**
3187  * Load an extension messages file
3188  * @deprecated in 1.16 (warnings in 1.18, removed in ?)
3189  */
3190 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
3191 }
3192
3193 /**
3194  * Get a platform-independent path to the null file, e.g.
3195  * /dev/null
3196  *
3197  * @return string
3198  */
3199 function wfGetNull() {
3200         return wfIsWindows()
3201                 ? 'NUL'
3202                 : '/dev/null';
3203 }
3204
3205 /**
3206  * Displays a maxlag error
3207  *
3208  * @param $host String: server that lags the most
3209  * @param $lag Integer: maxlag (actual)
3210  * @param $maxLag Integer: maxlag (requested)
3211  */
3212 function wfMaxlagError( $host, $lag, $maxLag ) {
3213         global $wgShowHostnames;
3214         header( 'HTTP/1.1 503 Service Unavailable' );
3215         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
3216         header( 'X-Database-Lag: ' . intval( $lag ) );
3217         header( 'Content-Type: text/plain' );
3218         if( $wgShowHostnames ) {
3219                 echo "Waiting for $host: $lag seconds lagged\n";
3220         } else {
3221                 echo "Waiting for a database server: $lag seconds lagged\n";
3222         }
3223 }
3224
3225 /**
3226  * Throws a warning that $function is deprecated
3227  * @param $function String
3228  * @return null
3229  */
3230 function wfDeprecated( $function ) {
3231         static $functionsWarned = array();
3232         if ( !isset( $functionsWarned[$function] ) ) {
3233                 $functionsWarned[$function] = true;
3234                 wfWarn( "Use of $function is deprecated.", 2 );
3235         }
3236 }
3237
3238 /**
3239  * Send a warning either to the debug log or in a PHP error depending on
3240  * $wgDevelopmentWarnings
3241  *
3242  * @param $msg String: message to send
3243  * @param $callerOffset Integer: number of itmes to go back in the backtrace to
3244  *        find the correct caller (1 = function calling wfWarn, ...)
3245  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3246  *        is true
3247  */
3248 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3249         $callers = wfDebugBacktrace();
3250         if( isset( $callers[$callerOffset + 1] ) ){
3251                 $callerfunc = $callers[$callerOffset + 1];
3252                 $callerfile = $callers[$callerOffset];
3253                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3254                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3255                 } else {
3256                         $file = '(internal function)';
3257                 }
3258                 $func = '';
3259                 if( isset( $callerfunc['class'] ) ) {
3260                         $func .= $callerfunc['class'] . '::';
3261                 }
3262                 $func .= @$callerfunc['function'];
3263                 $msg .= " [Called from $func in $file]";
3264         }
3265
3266         global $wgDevelopmentWarnings;
3267         if ( $wgDevelopmentWarnings ) {
3268                 trigger_error( $msg, $level );
3269         } else {
3270                 wfDebug( "$msg\n" );
3271         }
3272 }
3273
3274 /**
3275  * Sleep until the worst slave's replication lag is less than or equal to
3276  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
3277  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3278  * a no-op if there are no slaves.
3279  *
3280  * Every time the function has to wait for a slave, it will print a message to
3281  * that effect (and then sleep for a little while), so it's probably not best
3282  * to use this outside maintenance scripts in its present form.
3283  *
3284  * @param $maxLag Integer
3285  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3286  * @return null
3287  */
3288 function wfWaitForSlaves( $maxLag, $wiki = false ) {
3289         if( $maxLag ) {
3290                 $lb = wfGetLB( $wiki );
3291                 list( $host, $lag ) = $lb->getMaxLag( $wiki );
3292                 while( $lag > $maxLag ) {
3293                         $name = @gethostbyaddr( $host );
3294                         if( $name !== false ) {
3295                                 $host = $name;
3296                         }
3297                         print "Waiting for $host (lagged $lag seconds)...\n";
3298                         sleep( $maxLag );
3299                         list( $host, $lag ) = $lb->getMaxLag();
3300                 }
3301         }
3302 }
3303
3304 /**
3305  * Output some plain text in command-line mode or in the installer (updaters.inc).
3306  * Do not use it in any other context, its behaviour is subject to change.
3307  */
3308 function wfOut( $s ) {
3309         global $wgCommandLineMode;
3310         if ( $wgCommandLineMode && !defined( 'MEDIAWIKI_INSTALL' ) ) {
3311                 echo $s;
3312         } else {
3313                 echo htmlspecialchars( $s );
3314         }
3315         flush();
3316 }
3317
3318 /**
3319  * Count down from $n to zero on the terminal, with a one-second pause
3320  * between showing each number. For use in command-line scripts.
3321  */
3322 function wfCountDown( $n ) {
3323         for ( $i = $n; $i >= 0; $i-- ) {
3324                 if ( $i != $n ) {
3325                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3326                 }
3327                 echo $i;
3328                 flush();
3329                 if ( $i ) {
3330                         sleep( 1 );
3331                 }
3332         }
3333         echo "\n";
3334 }
3335
3336 /**
3337  * Generate a random 32-character hexadecimal token.
3338  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3339  *              characters before hashing.
3340  */
3341 function wfGenerateToken( $salt = '' ) {
3342         $salt = serialize( $salt );
3343
3344         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3345 }
3346
3347 /**
3348  * Replace all invalid characters with -
3349  * @param $name Mixed: filename to process
3350  */
3351 function wfStripIllegalFilenameChars( $name ) {
3352         global $wgIllegalFileChars;
3353         $name = wfBaseName( $name );
3354         $name = preg_replace(
3355                 "/[^" . Title::legalChars() . "]" .
3356                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3357                         "/",
3358                 '-',
3359                 $name
3360         );
3361         return $name;
3362 }
3363
3364 /**
3365  * Insert array into another array after the specified *KEY*
3366  * @param $array Array: The array.
3367  * @param $insert Array: The array to insert.
3368  * @param $after Mixed: The key to insert after
3369  */
3370 function wfArrayInsertAfter( $array, $insert, $after ) {
3371         // Find the offset of the element to insert after.
3372         $keys = array_keys( $array );
3373         $offsetByKey = array_flip( $keys );
3374
3375         $offset = $offsetByKey[$after];
3376
3377         // Insert at the specified offset
3378         $before = array_slice( $array, 0, $offset + 1, true );
3379         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
3380
3381         $output = $before + $insert + $after;
3382
3383         return $output;
3384 }
3385
3386 /* Recursively converts the parameter (an object) to an array with the same data */
3387 function wfObjectToArray( $object, $recursive = true ) {
3388         $array = array();
3389         foreach ( get_object_vars( $object ) as $key => $value ) {
3390                 if ( is_object( $value ) && $recursive ) {
3391                         $value = wfObjectToArray( $value );
3392                 }
3393
3394                 $array[$key] = $value;
3395         }
3396
3397         return $array;
3398 }
3399
3400 /**
3401  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3402  * @return Integer value memory was set to.
3403  */
3404 function wfMemoryLimit() {
3405         global $wgMemoryLimit;
3406         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3407         $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3408         if( $memlimit != -1 ) {
3409                 if( $conflimit == -1 ) {
3410                         wfDebug( "Removing PHP's memory limit\n" );
3411                         wfSuppressWarnings();
3412                         ini_set( 'memory_limit', $conflimit );
3413                         wfRestoreWarnings();
3414                         return $conflimit;
3415                 } elseif ( $conflimit > $memlimit ) {
3416                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3417                         wfSuppressWarnings();
3418                         ini_set( 'memory_limit', $conflimit );
3419                         wfRestoreWarnings();
3420                         return $conflimit;
3421                 }
3422         }
3423         return $memlimit;
3424 }
3425
3426 /**
3427  * Converts shorthand byte notation to integer form
3428  * @param $string String
3429  * @return Integer
3430  */
3431 function wfShorthandToInteger( $string = '' ) {
3432         $string = trim( $string );
3433         if( empty( $string ) ) {
3434                 return -1;
3435         }
3436         $last = strtolower( $string[strlen( $string ) - 1] );
3437         $val = intval( $string );
3438         switch( $last ) {
3439                 case 'g':
3440                         $val *= 1024;
3441                 case 'm':
3442                         $val *= 1024;
3443                 case 'k':
3444                         $val *= 1024;
3445         }
3446
3447         return $val;
3448 }
3449
3450 /**
3451  * Get the normalised IETF language tag
3452  * @param $code String: The language code.
3453  * @return $langCode String: The language code which complying with BCP 47 standards.
3454  */
3455 function wfBCP47( $code ) {
3456         $codeSegment = explode( '-', $code );
3457         foreach ( $codeSegment as $segNo => $seg ) {
3458                 if ( count( $codeSegment ) > 0 ) {
3459                         // ISO 3166 country code
3460                         if ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3461                                 $codeBCP[$segNo] = strtoupper( $seg );
3462                         // ISO 15924 script code
3463                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3464                                 $codeBCP[$segNo] = ucfirst( $seg );
3465                         // Use lowercase for other cases
3466                         } else {
3467                                 $codeBCP[$segNo] = strtolower( $seg );
3468                         }
3469                 } else {
3470                 // Use lowercase for single segment
3471                         $codeBCP[$segNo] = strtolower( $seg );
3472                 }
3473         }
3474         $langCode = implode( '-', $codeBCP );
3475         return $langCode;
3476 }
3477
3478 function wfArrayMap( $function, $input ) {
3479         $ret = array_map( $function, $input );
3480         foreach ( $ret as $key => $value ) {
3481                 $taint = istainted( $input[$key] );
3482                 if ( $taint ) {
3483                         taint( $ret[$key], $taint );
3484                 }
3485         }
3486         return $ret;
3487 }
3488
3489 /**
3490  * Returns the PackageRepository object for interaction with the package repository.
3491  *
3492  * TODO: Make the repository type also configurable.
3493  *
3494  * @since 1.17
3495  *
3496  * @return PackageRepository
3497  */
3498 function wfGetRepository() {
3499         global $wgRepositoryApiLocation;
3500         static $repository = false;
3501
3502         if ( $repository === false ) {
3503                 $repository = new DistributionRepository( $wgRepositoryApiLocation );
3504         }
3505
3506         return $repository;
3507 }