includes/GlobalFunctions.php

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