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 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /** @codeCoverageIgnore */
  24         function iconv( $from, $to, $string ) {
  25                 return Fallback::iconv( $from, $to, $string );
  26         }
  27 }
  28
  29 if ( !function_exists( 'mb_substr' ) ) {
  30         /** @codeCoverageIgnore */
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::mb_substr( $str, $start, $count );
  33         }
  34
  35         /** @codeCoverageIgnore */
  36         function mb_substr_split_unicode( $str, $splitPos ) {
  37                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  38         }
  39 }
  40
  41 if ( !function_exists( 'mb_strlen' ) ) {
  42         /** @codeCoverageIgnore */
  43         function mb_strlen( $str, $enc = '' ) {
  44                 return Fallback::mb_strlen( $str, $enc );
  45         }
  46 }
  47
  48 if( !function_exists( 'mb_strpos' ) ) {
  49         /** @codeCoverageIgnore */
  50         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  51                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  52         }
  53
  54 }
  55
  56 if( !function_exists( 'mb_strrpos' ) ) {
  57         /** @codeCoverageIgnore */
  58         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  59                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  60         }
  61 }
  62
  63
  64 // Support for Wietse Venema's taint feature
  65 if ( !function_exists( 'istainted' ) ) {
  66         /** @codeCoverageIgnore */
  67         function istainted( $var ) {
  68                 return 0;
  69         }
  70         /** @codeCoverageIgnore */
  71         function taint( $var, $level = 0 ) {}
  72         /** @codeCoverageIgnore */
  73         function untaint( $var, $level = 0 ) {}
  74         define( 'TC_HTML', 1 );
  75         define( 'TC_SHELL', 1 );
  76         define( 'TC_MYSQL', 1 );
  77         define( 'TC_PCRE', 1 );
  78         define( 'TC_SELF', 1 );
  79 }
  80 /// @endcond
  81
  82 /**
  83  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  84  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y') )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $s ) ) {
 298                 $needle = null;
 299                 return;
 300         }
 301
 302         if ( is_null( $needle ) ) {
 303                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 304                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 305                         $needle[] = '%3A';
 306                 }
 307         }
 308
 309         $s = urlencode( $s );
 310         $s = str_ireplace(
 311                 $needle,
 312                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 313                 $s
 314         );
 315
 316         return $s;
 317 }
 318
 319 /**
 320  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 321  * "days=7&limit=100". Options in the first array override options in the second.
 322  * Options set to "" will not be output.
 323  *
 324  * @param $array1 Array ( String|Array )
 325  * @param $array2 Array ( String|Array )
 326  * @param $prefix String
 327  * @return String
 328  */
 329 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 330         if ( !is_null( $array2 ) ) {
 331                 $array1 = $array1 + $array2;
 332         }
 333
 334         $cgi = '';
 335         foreach ( $array1 as $key => $value ) {
 336                 if ( $value !== '' ) {
 337                         if ( $cgi != '' ) {
 338                                 $cgi .= '&';
 339                         }
 340                         if ( $prefix !== '' ) {
 341                                 $key = $prefix . "[$key]";
 342                         }
 343                         if ( is_array( $value ) ) {
 344                                 $firstTime = true;
 345                                 foreach ( $value as $k => $v ) {
 346                                         $cgi .= $firstTime ? '' : '&';
 347                                         if ( is_array( $v ) ) {
 348                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 349                                         } else {
 350                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 351                                         }
 352                                         $firstTime = false;
 353                                 }
 354                         } else {
 355                                 if ( is_object( $value ) ) {
 356                                         $value = $value->__toString();
 357                                 }
 358                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 359                         }
 360                 }
 361         }
 362         return $cgi;
 363 }
 364
 365 /**
 366  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 367  * its argument and returns the same string in array form.  This allows compa-
 368  * tibility with legacy functions that accept raw query strings instead of nice
 369  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
 370  * valid query strings, or it will explode.
 371  *
 372  * @param $query String: query string
 373  * @return array Array version of input
 374  */
 375 function wfCgiToArray( $query ) {
 376         if ( isset( $query[0] ) && $query[0] == '?' ) {
 377                 $query = substr( $query, 1 );
 378         }
 379         $bits = explode( '&', $query );
 380         $ret = array();
 381         foreach ( $bits as $bit ) {
 382                 if ( $bit === '' ) {
 383                         continue;
 384                 }
 385                 list( $key, $value ) = explode( '=', $bit );
 386                 $key = urldecode( $key );
 387                 $value = urldecode( $value );
 388                 if ( strpos( $key, '[' ) !== false ) {
 389                         $keys = array_reverse( explode( '[', $key ) );
 390                         $key = array_pop( $keys );
 391                         $temp = $value;
 392                         foreach ( $keys as $k ) {
 393                                 $k = substr( $k, 0, -1 );
 394                                 $temp = array( $k => $temp );
 395                         }
 396                         if ( isset( $ret[$key] ) ) {
 397                                 $ret[$key] = array_merge( $ret[$key], $temp );
 398                         } else {
 399                                 $ret[$key] = $temp;
 400                         }
 401                 } else {
 402                         $ret[$key] = $value;
 403                 }
 404         }
 405         return $ret;
 406 }
 407
 408 /**
 409  * Append a query string to an existing URL, which may or may not already
 410  * have query string parameters already. If so, they will be combined.
 411  *
 412  * @param $url String
 413  * @param $query Mixed: string or associative array
 414  * @return string
 415  */
 416 function wfAppendQuery( $url, $query ) {
 417         if ( is_array( $query ) ) {
 418                 $query = wfArrayToCGI( $query );
 419         }
 420         if( $query != '' ) {
 421                 if( false === strpos( $url, '?' ) ) {
 422                         $url .= '?';
 423                 } else {
 424                         $url .= '&';
 425                 }
 426                 $url .= $query;
 427         }
 428         return $url;
 429 }
 430
 431 /**
 432  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 433  * is correct.
 434  *
 435  * The meaning of the PROTO_* constants is as follows:
 436  * PROTO_HTTP: Output a URL starting with http://
 437  * PROTO_HTTPS: Output a URL starting with https://
 438  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 439  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 440  *
 441  * @todo this won't work with current-path-relative URLs
 442  * like "subdir/foo.html", etc.
 443  *
 444  * @param $url String: either fully-qualified or a local path + query
 445  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 446  * @return string Fully-qualified URL
 447  */
 448 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 449         global $wgServer;
 450         if ( $defaultProto === PROTO_CURRENT ) {
 451                 $defaultProto = WebRequest::detectProtocol() . '://';
 452         }
 453
 454         // Analyze $wgServer to obtain its protocol
 455         $bits = wfParseUrl( $wgServer );
 456         $serverHasProto = $bits && $bits['scheme'] != '';
 457         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 458
 459         if( substr( $url, 0, 2 ) == '//' ) {
 460                 return $defaultProtoWithoutSlashes . $url;
 461         } elseif( substr( $url, 0, 1 ) == '/' ) {
 462                 // If $wgServer is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 463                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $wgServer . $url;
 464         } else {
 465                 return $url;
 466         }
 467 }
 468
 469 /**
 470  * Returns a regular expression of url protocols
 471  *
 472  * @return String
 473  */
 474 function wfUrlProtocols() {
 475         global $wgUrlProtocols;
 476
 477         static $retval = null;
 478         if ( !is_null( $retval ) ) {
 479                 return $retval;
 480         }
 481
 482         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 483         // with LocalSettings files from 1.5
 484         if ( is_array( $wgUrlProtocols ) ) {
 485                 $protocols = array();
 486                 foreach ( $wgUrlProtocols as $protocol ) {
 487                         $protocols[] = preg_quote( $protocol, '/' );
 488                 }
 489
 490                 $retval = implode( '|', $protocols );
 491         } else {
 492                 $retval = $wgUrlProtocols;
 493         }
 494         return $retval;
 495 }
 496
 497 /**
 498  * parse_url() work-alike, but non-broken.  Differences:
 499  *
 500  * 1) Does not raise warnings on bad URLs (just returns false)
 501  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 502  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 503  *
 504  * @param $url String: a URL to parse
 505  * @return Array: bits of the URL in an associative array, per PHP docs
 506  */
 507 function wfParseUrl( $url ) {
 508         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 509
 510         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 511         // way to handle them is to just prepend 'http:' and strip the protocol out later
 512         $wasRelative = substr( $url, 0, 2 ) == '//';
 513         if ( $wasRelative ) {
 514                 $url = "http:$url";
 515         }
 516         wfSuppressWarnings();
 517         $bits = parse_url( $url );
 518         wfRestoreWarnings();
 519         if ( !$bits ) {
 520                 return false;
 521         }
 522
 523         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 524         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 525                 $bits['delimiter'] = '://';
 526         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 527                 $bits['delimiter'] = ':';
 528                 // parse_url detects for news: and mailto: the host part of an url as path
 529                 // We have to correct this wrong detection
 530                 if ( isset( $bits['path'] ) ) {
 531                         $bits['host'] = $bits['path'];
 532                         $bits['path'] = '';
 533                 }
 534         } else {
 535                 return false;
 536         }
 537
 538         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 539         if ( !isset( $bits['host'] ) ) {
 540                 $bits['host'] = '';
 541
 542                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 543                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 544                         $bits['path'] = '/' . $bits['path'];
 545                 }
 546         }
 547
 548         // If the URL was protocol-relative, fix scheme and delimiter
 549         if ( $wasRelative ) {
 550                 $bits['scheme'] = '';
 551                 $bits['delimiter'] = '//';
 552         }
 553         return $bits;
 554 }
 555
 556 /**
 557  * Make a URL index, appropriate for the el_index field of externallinks.
 558  *
 559  * @param $url String
 560  * @return String
 561  */
 562 function wfMakeUrlIndex( $url ) {
 563         $bits = wfParseUrl( $url );
 564
 565         // Reverse the labels in the hostname, convert to lower case
 566         // For emails reverse domainpart only
 567         if ( $bits['scheme'] == 'mailto' ) {
 568                 $mailparts = explode( '@', $bits['host'], 2 );
 569                 if ( count( $mailparts ) === 2 ) {
 570                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 571                 } else {
 572                         // No domain specified, don't mangle it
 573                         $domainpart = '';
 574                 }
 575                 $reversedHost = $domainpart . '@' . $mailparts[0];
 576         } else {
 577                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 578         }
 579         // Add an extra dot to the end
 580         // Why? Is it in wrong place in mailto links?
 581         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 582                 $reversedHost .= '.';
 583         }
 584         // Reconstruct the pseudo-URL
 585         $prot = $bits['scheme'];
 586         $index = $prot . $bits['delimiter'] . $reversedHost;
 587         // Leave out user and password. Add the port, path, query and fragment
 588         if ( isset( $bits['port'] ) ) {
 589                 $index .= ':' . $bits['port'];
 590         }
 591         if ( isset( $bits['path'] ) ) {
 592                 $index .= $bits['path'];
 593         } else {
 594                 $index .= '/';
 595         }
 596         if ( isset( $bits['query'] ) ) {
 597                 $index .= '?' . $bits['query'];
 598         }
 599         if ( isset( $bits['fragment'] ) ) {
 600                 $index .= '#' . $bits['fragment'];
 601         }
 602         return $index;
 603 }
 604
 605 /**
 606  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 607  * In normal operation this is a NOP.
 608  *
 609  * Controlling globals:
 610  * $wgDebugLogFile - points to the log file
 611  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 612  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 613  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 614  *
 615  * @param $text String
 616  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 617  */
 618 function wfDebug( $text, $logonly = false ) {
 619         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 620         global $wgDebugLogPrefix, $wgShowDebug;
 621
 622         static $cache = array(); // Cache of unoutputted messages
 623         $text = wfDebugTimer() . $text;
 624
 625         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 626                 return;
 627         }
 628
 629         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 630                 $cache[] = $text;
 631
 632                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 633                         // add the message and any cached messages to the output
 634                         array_map( array( $wgOut, 'debug' ), $cache );
 635                         $cache = array();
 636                 }
 637         }
 638         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 639                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 640                         # Strip unprintables; they can switch terminal modes when binary data
 641                         # gets dumped, which is pretty annoying.
 642                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 643                         $text = $wgDebugLogPrefix . $text;
 644                         wfErrorLog( $text, $wgDebugLogFile );
 645                 }
 646         }
 647 }
 648
 649 /**
 650  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 651  */
 652 function wfIsDebugRawPage() {
 653         static $cache;
 654         if ( $cache !== null ) {
 655                 return $cache;
 656         }
 657         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 658         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 659                 || (
 660                         isset( $_SERVER['SCRIPT_NAME'] )
 661                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 662                 ) )
 663         {
 664                 $cache = true;
 665         } else {
 666                 $cache = false;
 667         }
 668         return $cache;
 669 }
 670
 671 /**
 672  * Get microsecond timestamps for debug logs
 673  *
 674  * @return string
 675  */
 676 function wfDebugTimer() {
 677         global $wgDebugTimestamps;
 678         if ( !$wgDebugTimestamps ) {
 679                 return '';
 680         }
 681         static $start = null;
 682
 683         if ( $start === null ) {
 684                 $start = microtime( true );
 685                 $prefix = "\n$start";
 686         } else {
 687                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 688         }
 689
 690         return $prefix . '  ';
 691 }
 692
 693 /**
 694  * Send a line giving PHP memory usage.
 695  *
 696  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 697  */
 698 function wfDebugMem( $exact = false ) {
 699         $mem = memory_get_usage();
 700         if( !$exact ) {
 701                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 702         } else {
 703                 $mem .= ' bytes';
 704         }
 705         wfDebug( "Memory usage: $mem\n" );
 706 }
 707
 708 /**
 709  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 710  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 711  *
 712  * @param $logGroup String
 713  * @param $text String
 714  * @param $public Bool: whether to log the event in the public log if no private
 715  *                     log file is specified, (default true)
 716  */
 717 function wfDebugLog( $logGroup, $text, $public = true ) {
 718         global $wgDebugLogGroups, $wgShowHostnames;
 719         $text = trim( $text ) . "\n";
 720         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 721                 $time = wfTimestamp( TS_DB );
 722                 $wiki = wfWikiID();
 723                 if ( $wgShowHostnames ) {
 724                         $host = wfHostname();
 725                 } else {
 726                         $host = '';
 727                 }
 728                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 729                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 730                 }
 731         } elseif ( $public === true ) {
 732                 wfDebug( $text, true );
 733         }
 734 }
 735
 736 /**
 737  * Log for database errors
 738  *
 739  * @param $text String: database error message.
 740  */
 741 function wfLogDBError( $text ) {
 742         global $wgDBerrorLog, $wgDBname;
 743         if ( $wgDBerrorLog ) {
 744                 $host = trim(`hostname`);
 745                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 746                 wfErrorLog( $text, $wgDBerrorLog );
 747         }
 748 }
 749
 750 /**
 751  * Log to a file without getting "file size exceeded" signals.
 752  *
 753  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 754  * send lines to the specified port, prefixed by the specified prefix and a space.
 755  *
 756  * @param $text String
 757  * @param $file String filename
 758  */
 759 function wfErrorLog( $text, $file ) {
 760         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 761                 # Needs the sockets extension
 762                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 763                         // IPv6 bracketed host
 764                         $host = $m[2];
 765                         $port = intval( $m[3] );
 766                         $prefix = isset( $m[4] ) ? $m[4] : false;
 767                         $domain = AF_INET6;
 768                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 769                         $host = $m[2];
 770                         if ( !IP::isIPv4( $host ) ) {
 771                                 $host = gethostbyname( $host );
 772                         }
 773                         $port = intval( $m[3] );
 774                         $prefix = isset( $m[4] ) ? $m[4] : false;
 775                         $domain = AF_INET;
 776                 } else {
 777                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 778                 }
 779
 780                 // Clean it up for the multiplexer
 781                 if ( strval( $prefix ) !== '' ) {
 782                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 783
 784                         // Limit to 64KB
 785                         if ( strlen( $text ) > 65534 ) {
 786                                 $text = substr( $text, 0, 65534 );
 787                         }
 788
 789                         if ( substr( $text, -1 ) != "\n" ) {
 790                                 $text .= "\n";
 791                         }
 792                 } elseif ( strlen( $text ) > 65535 ) {
 793                         $text = substr( $text, 0, 65535 );
 794                 }
 795
 796                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 797                 if ( !$sock ) {
 798                         return;
 799                 }
 800                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 801                 socket_close( $sock );
 802         } else {
 803                 wfSuppressWarnings();
 804                 $exists = file_exists( $file );
 805                 $size = $exists ? filesize( $file ) : false;
 806                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 807                         file_put_contents( $file, $text, FILE_APPEND );
 808                 }
 809                 wfRestoreWarnings();
 810         }
 811 }
 812
 813 /**
 814  * @todo document
 815  */
 816 function wfLogProfilingData() {
 817         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 818         global $wgProfileLimit, $wgUser;
 819
 820         $profiler = Profiler::instance();
 821
 822         # Profiling must actually be enabled...
 823         if ( $profiler->isStub() ) {
 824                 return;
 825         }
 826
 827         // Get total page request time and only show pages that longer than
 828         // $wgProfileLimit time (default is 0)
 829         $now = wfTime();
 830         $elapsed = $now - $wgRequestTime;
 831         if ( $elapsed <= $wgProfileLimit ) {
 832                 return;
 833         }
 834
 835         $profiler->logData();
 836
 837         // Check whether this should be logged in the debug file.
 838         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 839                 return;
 840         }
 841
 842         $forward = '';
 843         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 844                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 845         }
 846         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 847                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 848         }
 849         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 850                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 851         }
 852         if ( $forward ) {
 853                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 854         }
 855         // Don't load $wgUser at this late stage just for statistics purposes
 856         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 857         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 858                 $forward .= ' anon';
 859         }
 860         $log = sprintf( "%s\t%04.3f\t%s\n",
 861                 gmdate( 'YmdHis' ), $elapsed,
 862                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 863
 864         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 865 }
 866
 867 /**
 868  * Check if the wiki read-only lock file is present. This can be used to lock
 869  * off editing functions, but doesn't guarantee that the database will not be
 870  * modified.
 871  *
 872  * @return bool
 873  */
 874 function wfReadOnly() {
 875         global $wgReadOnlyFile, $wgReadOnly;
 876
 877         if ( !is_null( $wgReadOnly ) ) {
 878                 return (bool)$wgReadOnly;
 879         }
 880         if ( $wgReadOnlyFile == '' ) {
 881                 return false;
 882         }
 883         // Set $wgReadOnly for faster access next time
 884         if ( is_file( $wgReadOnlyFile ) ) {
 885                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 886         } else {
 887                 $wgReadOnly = false;
 888         }
 889         return (bool)$wgReadOnly;
 890 }
 891
 892 function wfReadOnlyReason() {
 893         global $wgReadOnly;
 894         wfReadOnly();
 895         return $wgReadOnly;
 896 }
 897
 898 /**
 899  * Return a Language object from $langcode
 900  *
 901  * @param $langcode Mixed: either:
 902  *                  - a Language object
 903  *                  - code of the language to get the message for, if it is
 904  *                    a valid code create a language for that language, if
 905  *                    it is a string but not a valid code then make a basic
 906  *                    language object
 907  *                  - a boolean: if it's false then use the current users
 908  *                    language (as a fallback for the old parameter
 909  *                    functionality), or if it is true then use the wikis
 910  * @return Language object
 911  */
 912 function wfGetLangObj( $langcode = false ) {
 913         # Identify which language to get or create a language object for.
 914         # Using is_object here due to Stub objects.
 915         if( is_object( $langcode ) ) {
 916                 # Great, we already have the object (hopefully)!
 917                 return $langcode;
 918         }
 919
 920         global $wgContLang, $wgLanguageCode;
 921         if( $langcode === true || $langcode === $wgLanguageCode ) {
 922                 # $langcode is the language code of the wikis content language object.
 923                 # or it is a boolean and value is true
 924                 return $wgContLang;
 925         }
 926
 927         global $wgLang;
 928         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 929                 # $langcode is the language code of user language object.
 930                 # or it was a boolean and value is false
 931                 return $wgLang;
 932         }
 933
 934         $validCodes = array_keys( Language::getLanguageNames() );
 935         if( in_array( $langcode, $validCodes ) ) {
 936                 # $langcode corresponds to a valid language.
 937                 return Language::factory( $langcode );
 938         }
 939
 940         # $langcode is a string, but not a valid language code; use content language.
 941         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 942         return $wgContLang;
 943 }
 944
 945 /**
 946  * Old function when $wgBetterDirectionality existed
 947  * Removed in core, kept in extensions for backwards compat.
 948  *
 949  * @deprecated since 1.18
 950  * @return Language
 951  */
 952 function wfUILang() {
 953         global $wgLang;
 954         return $wgLang;
 955 }
 956
 957 /**
 958  * This is the new function for getting translated interface messages.
 959  * See the Message class for documentation how to use them.
 960  * The intention is that this function replaces all old wfMsg* functions.
 961  * @param $key \string Message key.
 962  * Varargs: normal message parameters.
 963  * @return Message
 964  * @since 1.17
 965  */
 966 function wfMessage( $key /*...*/) {
 967         $params = func_get_args();
 968         array_shift( $params );
 969         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 970                 $params = $params[0];
 971         }
 972         return new Message( $key, $params );
 973 }
 974
 975 /**
 976  * This function accepts multiple message keys and returns a message instance
 977  * for the first message which is non-empty. If all messages are empty then an
 978  * instance of the first message key is returned.
 979  * @param varargs: message keys
 980  * @return Message
 981  * @since 1.18
 982  */
 983 function wfMessageFallback( /*...*/ ) {
 984         $args = func_get_args();
 985         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
 986 }
 987
 988 /**
 989  * Get a message from anywhere, for the current user language.
 990  *
 991  * Use wfMsgForContent() instead if the message should NOT
 992  * change depending on the user preferences.
 993  *
 994  * @param $key String: lookup key for the message, usually
 995  *    defined in languages/Language.php
 996  *
 997  * Parameters to the message, which can be used to insert variable text into
 998  * it, can be passed to this function in the following formats:
 999  * - One per argument, starting at the second parameter
1000  * - As an array in the second parameter
1001  * These are not shown in the function definition.
1002  *
1003  * @return String
1004  */
1005 function wfMsg( $key ) {
1006         $args = func_get_args();
1007         array_shift( $args );
1008         return wfMsgReal( $key, $args );
1009 }
1010
1011 /**
1012  * Same as above except doesn't transform the message
1013  *
1014  * @param $key String
1015  * @return String
1016  */
1017 function wfMsgNoTrans( $key ) {
1018         $args = func_get_args();
1019         array_shift( $args );
1020         return wfMsgReal( $key, $args, true, false, false );
1021 }
1022
1023 /**
1024  * Get a message from anywhere, for the current global language
1025  * set with $wgLanguageCode.
1026  *
1027  * Use this if the message should NOT change dependent on the
1028  * language set in the user's preferences. This is the case for
1029  * most text written into logs, as well as link targets (such as
1030  * the name of the copyright policy page). Link titles, on the
1031  * other hand, should be shown in the UI language.
1032  *
1033  * Note that MediaWiki allows users to change the user interface
1034  * language in their preferences, but a single installation
1035  * typically only contains content in one language.
1036  *
1037  * Be wary of this distinction: If you use wfMsg() where you should
1038  * use wfMsgForContent(), a user of the software may have to
1039  * customize potentially hundreds of messages in
1040  * order to, e.g., fix a link in every possible language.
1041  *
1042  * @param $key String: lookup key for the message, usually
1043  *     defined in languages/Language.php
1044  * @return String
1045  */
1046 function wfMsgForContent( $key ) {
1047         global $wgForceUIMsgAsContentMsg;
1048         $args = func_get_args();
1049         array_shift( $args );
1050         $forcontent = true;
1051         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1052                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1053         {
1054                 $forcontent = false;
1055         }
1056         return wfMsgReal( $key, $args, true, $forcontent );
1057 }
1058
1059 /**
1060  * Same as above except doesn't transform the message
1061  *
1062  * @param $key String
1063  * @return String
1064  */
1065 function wfMsgForContentNoTrans( $key ) {
1066         global $wgForceUIMsgAsContentMsg;
1067         $args = func_get_args();
1068         array_shift( $args );
1069         $forcontent = true;
1070         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1071                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1072         {
1073                 $forcontent = false;
1074         }
1075         return wfMsgReal( $key, $args, true, $forcontent, false );
1076 }
1077
1078 /**
1079  * Really get a message
1080  *
1081  * @param $key String: key to get.
1082  * @param $args
1083  * @param $useDB Boolean
1084  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1085  * @param $transform Boolean: Whether or not to transform the message.
1086  * @return String: the requested message.
1087  */
1088 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1089         wfProfileIn( __METHOD__ );
1090         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1091         $message = wfMsgReplaceArgs( $message, $args );
1092         wfProfileOut( __METHOD__ );
1093         return $message;
1094 }
1095
1096 /**
1097  * Fetch a message string value, but don't replace any keys yet.
1098  *
1099  * @param $key String
1100  * @param $useDB Bool
1101  * @param $langCode String: Code of the language to get the message for, or
1102  *                  behaves as a content language switch if it is a boolean.
1103  * @param $transform Boolean: whether to parse magic words, etc.
1104  * @return string
1105  */
1106 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1107         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1108
1109         $cache = MessageCache::singleton();
1110         $message = $cache->get( $key, $useDB, $langCode );
1111         if( $message === false ) {
1112                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1113         } elseif ( $transform ) {
1114                 $message = $cache->transform( $message );
1115         }
1116         return $message;
1117 }
1118
1119 /**
1120  * Replace message parameter keys on the given formatted output.
1121  *
1122  * @param $message String
1123  * @param $args Array
1124  * @return string
1125  * @private
1126  */
1127 function wfMsgReplaceArgs( $message, $args ) {
1128         # Fix windows line-endings
1129         # Some messages are split with explode("\n", $msg)
1130         $message = str_replace( "\r", '', $message );
1131
1132         // Replace arguments
1133         if ( count( $args ) ) {
1134                 if ( is_array( $args[0] ) ) {
1135                         $args = array_values( $args[0] );
1136                 }
1137                 $replacementKeys = array();
1138                 foreach( $args as $n => $param ) {
1139                         $replacementKeys['$' . ( $n + 1 )] = $param;
1140                 }
1141                 $message = strtr( $message, $replacementKeys );
1142         }
1143
1144         return $message;
1145 }
1146
1147 /**
1148  * Return an HTML-escaped version of a message.
1149  * Parameter replacements, if any, are done *after* the HTML-escaping,
1150  * so parameters may contain HTML (eg links or form controls). Be sure
1151  * to pre-escape them if you really do want plaintext, or just wrap
1152  * the whole thing in htmlspecialchars().
1153  *
1154  * @param $key String
1155  * @param string ... parameters
1156  * @return string
1157  */
1158 function wfMsgHtml( $key ) {
1159         $args = func_get_args();
1160         array_shift( $args );
1161         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1162 }
1163
1164 /**
1165  * Return an HTML version of message
1166  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1167  * so parameters may contain HTML (eg links or form controls). Be sure
1168  * to pre-escape them if you really do want plaintext, or just wrap
1169  * the whole thing in htmlspecialchars().
1170  *
1171  * @param $key String
1172  * @param string ... parameters
1173  * @return string
1174  */
1175 function wfMsgWikiHtml( $key ) {
1176         $args = func_get_args();
1177         array_shift( $args );
1178         return wfMsgReplaceArgs(
1179                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null, /* can't be set to false */ true )->getText(),
1180                 $args );
1181 }
1182
1183 /**
1184  * Returns message in the requested format
1185  * @param $key String: key of the message
1186  * @param $options Array: processing rules. Can take the following options:
1187  *   <i>parse</i>: parses wikitext to HTML
1188  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1189  *       p's added by parser or tidy
1190  *   <i>escape</i>: filters message through htmlspecialchars
1191  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1192  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1193  *   <i>parsemag</i>: transform the message using magic phrases
1194  *   <i>content</i>: fetch message for content language instead of interface
1195  * Also can accept a single associative argument, of the form 'language' => 'xx':
1196  *   <i>language</i>: Language object or language code to fetch message for
1197  *       (overriden by <i>content</i>).
1198  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1199  *
1200  * @return String
1201  */
1202 function wfMsgExt( $key, $options ) {
1203         $args = func_get_args();
1204         array_shift( $args );
1205         array_shift( $args );
1206         $options = (array)$options;
1207
1208         foreach( $options as $arrayKey => $option ) {
1209                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1210                         # An unknown index, neither numeric nor "language"
1211                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1212                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1213                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1214                 'replaceafter', 'parsemag', 'content' ) ) ) {
1215                         # A numeric index with unknown value
1216                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1217                 }
1218         }
1219
1220         if( in_array( 'content', $options, true ) ) {
1221                 $forContent = true;
1222                 $langCode = true;
1223                 $langCodeObj = null;
1224         } elseif( array_key_exists( 'language', $options ) ) {
1225                 $forContent = false;
1226                 $langCode = wfGetLangObj( $options['language'] );
1227                 $langCodeObj = $langCode;
1228         } else {
1229                 $forContent = false;
1230                 $langCode = false;
1231                 $langCodeObj = null;
1232         }
1233
1234         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1235
1236         if( !in_array( 'replaceafter', $options, true ) ) {
1237                 $string = wfMsgReplaceArgs( $string, $args );
1238         }
1239
1240         $messageCache = MessageCache::singleton();
1241         if( in_array( 'parse', $options, true ) ) {
1242                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1243         } elseif ( in_array( 'parseinline', $options, true ) ) {
1244                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1245                 $m = array();
1246                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1247                         $string = $m[1];
1248                 }
1249         } elseif ( in_array( 'parsemag', $options, true ) ) {
1250                 $string = $messageCache->transform( $string,
1251                                 !$forContent, $langCodeObj );
1252         }
1253
1254         if ( in_array( 'escape', $options, true ) ) {
1255                 $string = htmlspecialchars ( $string );
1256         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1257                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1258         }
1259
1260         if( in_array( 'replaceafter', $options, true ) ) {
1261                 $string = wfMsgReplaceArgs( $string, $args );
1262         }
1263
1264         return $string;
1265 }
1266
1267 /**
1268  * Since wfMsg() and co suck, they don't return false if the message key they
1269  * looked up didn't exist but a XHTML string, this function checks for the
1270  * nonexistance of messages by checking the MessageCache::get() result directly.
1271  *
1272  * @param $key      String: the message key looked up
1273  * @return Boolean True if the message *doesn't* exist.
1274  */
1275 function wfEmptyMsg( $key ) {
1276         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1277 }
1278
1279 /**
1280  * Throw a debugging exception. This function previously once exited the process,
1281  * but now throws an exception instead, with similar results.
1282  *
1283  * @param $msg String: message shown when dieing.
1284  */
1285 function wfDebugDieBacktrace( $msg = '' ) {
1286         throw new MWException( $msg );
1287 }
1288
1289 /**
1290  * Fetch server name for use in error reporting etc.
1291  * Use real server name if available, so we know which machine
1292  * in a server farm generated the current page.
1293  *
1294  * @return string
1295  */
1296 function wfHostname() {
1297         static $host;
1298         if ( is_null( $host ) ) {
1299                 if ( function_exists( 'posix_uname' ) ) {
1300                         // This function not present on Windows
1301                         $uname = posix_uname();
1302                 } else {
1303                         $uname = false;
1304                 }
1305                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1306                         $host = $uname['nodename'];
1307                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1308                         # Windows computer name
1309                         $host = getenv( 'COMPUTERNAME' );
1310                 } else {
1311                         # This may be a virtual server.
1312                         $host = $_SERVER['SERVER_NAME'];
1313                 }
1314         }
1315         return $host;
1316 }
1317
1318 /**
1319  * Returns a HTML comment with the elapsed time since request.
1320  * This method has no side effects.
1321  *
1322  * @return string
1323  */
1324 function wfReportTime() {
1325         global $wgRequestTime, $wgShowHostnames;
1326
1327         $now = wfTime();
1328         $elapsed = $now - $wgRequestTime;
1329
1330         return $wgShowHostnames
1331                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1332                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1333 }
1334
1335 /**
1336  * Safety wrapper for debug_backtrace().
1337  *
1338  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1339  * murky circumstances, which may be triggered in part by stub objects
1340  * or other fancy talkin'.
1341  *
1342  * Will return an empty array if Zend Optimizer is detected or if
1343  * debug_backtrace is disabled, otherwise the output from
1344  * debug_backtrace() (trimmed).
1345  *
1346  * @return array of backtrace information
1347  */
1348 function wfDebugBacktrace( $limit = 0 ) {
1349         static $disabled = null;
1350
1351         if( extension_loaded( 'Zend Optimizer' ) ) {
1352                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1353                 return array();
1354         }
1355
1356         if ( is_null( $disabled ) ) {
1357                 $disabled = false;
1358                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1359                 $functions = array_map( 'trim', $functions );
1360                 $functions = array_map( 'strtolower', $functions );
1361                 if ( in_array( 'debug_backtrace', $functions ) ) {
1362                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1363                         $disabled = true;
1364                 }
1365         }
1366         if ( $disabled ) {
1367                 return array();
1368         }
1369
1370         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1371                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, 1 ), 1 );
1372         } else {
1373                 return array_slice( debug_backtrace(), 1 );
1374         }
1375 }
1376
1377 /**
1378  * Get a debug backtrace as a string
1379  *
1380  * @return string
1381  */
1382 function wfBacktrace() {
1383         global $wgCommandLineMode;
1384
1385         if ( $wgCommandLineMode ) {
1386                 $msg = '';
1387         } else {
1388                 $msg = "<ul>\n";
1389         }
1390         $backtrace = wfDebugBacktrace();
1391         foreach( $backtrace as $call ) {
1392                 if( isset( $call['file'] ) ) {
1393                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1394                         $file = $f[count( $f ) - 1];
1395                 } else {
1396                         $file = '-';
1397                 }
1398                 if( isset( $call['line'] ) ) {
1399                         $line = $call['line'];
1400                 } else {
1401                         $line = '-';
1402                 }
1403                 if ( $wgCommandLineMode ) {
1404                         $msg .= "$file line $line calls ";
1405                 } else {
1406                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1407                 }
1408                 if( !empty( $call['class'] ) ) {
1409                         $msg .= $call['class'] . $call['type'];
1410                 }
1411                 $msg .= $call['function'] . '()';
1412
1413                 if ( $wgCommandLineMode ) {
1414                         $msg .= "\n";
1415                 } else {
1416                         $msg .= "</li>\n";
1417                 }
1418         }
1419         if ( $wgCommandLineMode ) {
1420                 $msg .= "\n";
1421         } else {
1422                 $msg .= "</ul>\n";
1423         }
1424
1425         return $msg;
1426 }
1427
1428 /**
1429  * Get the name of the function which called this function
1430  *
1431  * @param $level Int
1432  * @return Bool|string
1433  */
1434 function wfGetCaller( $level = 2 ) {
1435         $backtrace = wfDebugBacktrace( $level );
1436         if ( isset( $backtrace[$level] ) ) {
1437                 return wfFormatStackFrame( $backtrace[$level] );
1438         } else {
1439                 $caller = 'unknown';
1440         }
1441         return $caller;
1442 }
1443
1444 /**
1445  * Return a string consisting of callers in the stack. Useful sometimes
1446  * for profiling specific points.
1447  *
1448  * @param $limit The maximum depth of the stack frame to return, or false for
1449  *               the entire stack.
1450  * @return String
1451  */
1452 function wfGetAllCallers( $limit = 3 ) {
1453         $trace = array_reverse( wfDebugBacktrace() );
1454         if ( !$limit || $limit > count( $trace ) - 1 ) {
1455                 $limit = count( $trace ) - 1;
1456         }
1457         $trace = array_slice( $trace, -$limit - 1, $limit );
1458         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1459 }
1460
1461 /**
1462  * Return a string representation of frame
1463  *
1464  * @param $frame Array
1465  * @return Bool
1466  */
1467 function wfFormatStackFrame( $frame ) {
1468         return isset( $frame['class'] ) ?
1469                 $frame['class'] . '::' . $frame['function'] :
1470                 $frame['function'];
1471 }
1472
1473
1474 /* Some generic result counters, pulled out of SearchEngine */
1475
1476
1477 /**
1478  * @todo document
1479  *
1480  * @param $offset Int
1481  * @param $limit Int
1482  * @return String
1483  */
1484 function wfShowingResults( $offset, $limit ) {
1485         global $wgLang;
1486         return wfMsgExt(
1487                 'showingresults',
1488                 array( 'parseinline' ),
1489                 $wgLang->formatNum( $limit ),
1490                 $wgLang->formatNum( $offset + 1 )
1491         );
1492 }
1493
1494 /**
1495  * Generate (prev x| next x) (20|50|100...) type links for paging
1496  *
1497  * @param $offset String
1498  * @param $limit Integer
1499  * @param $link String
1500  * @param $query String: optional URL query parameter string
1501  * @param $atend Bool: optional param for specified if this is the last page
1502  * @return String
1503  */
1504 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1505         global $wgLang;
1506         $fmtLimit = $wgLang->formatNum( $limit );
1507         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1508         # Get prev/next link display text
1509         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1510         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1511         # Get prev/next link title text
1512         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1513         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1514         # Fetch the title object
1515         if( is_object( $link ) ) {
1516                 $title =& $link;
1517         } else {
1518                 $title = Title::newFromText( $link );
1519                 if( is_null( $title ) ) {
1520                         return false;
1521                 }
1522         }
1523         # Make 'previous' link
1524         if( 0 != $offset ) {
1525                 $po = $offset - $limit;
1526                 $po = max( $po, 0 );
1527                 $q = "limit={$limit}&offset={$po}";
1528                 if( $query != '' ) {
1529                         $q .= '&' . $query;
1530                 }
1531                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1532         } else {
1533                 $plink = $prev;
1534         }
1535         # Make 'next' link
1536         $no = $offset + $limit;
1537         $q = "limit={$limit}&offset={$no}";
1538         if( $query != '' ) {
1539                 $q .= '&' . $query;
1540         }
1541         if( $atend ) {
1542                 $nlink = $next;
1543         } else {
1544                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1545         }
1546         # Make links to set number of items per page
1547         $nums = $wgLang->pipeList( array(
1548                 wfNumLink( $offset, 20, $title, $query ),
1549                 wfNumLink( $offset, 50, $title, $query ),
1550                 wfNumLink( $offset, 100, $title, $query ),
1551                 wfNumLink( $offset, 250, $title, $query ),
1552                 wfNumLink( $offset, 500, $title, $query )
1553         ) );
1554         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1555 }
1556
1557 /**
1558  * Generate links for (20|50|100...) items-per-page links
1559  *
1560  * @param $offset String
1561  * @param $limit Integer
1562  * @param $title Title
1563  * @param $query String: optional URL query parameter string
1564  */
1565 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1566         global $wgLang;
1567         if( $query == '' ) {
1568                 $q = '';
1569         } else {
1570                 $q = $query.'&';
1571         }
1572         $q .= "limit={$limit}&offset={$offset}";
1573         $fmtLimit = $wgLang->formatNum( $limit );
1574         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1575         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1576         return $s;
1577 }
1578
1579 /**
1580  * @todo document
1581  * @todo FIXME: We may want to blacklist some broken browsers
1582  *
1583  * @param $force Bool
1584  * @return bool Whereas client accept gzip compression
1585  */
1586 function wfClientAcceptsGzip( $force = false ) {
1587         static $result = null;
1588         if ( $result === null || $force ) {
1589                 $result = false;
1590                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1591                         # @todo FIXME: We may want to blacklist some broken browsers
1592                         $m = array();
1593                         if( preg_match(
1594                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1595                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1596                                 $m )
1597                         )
1598                         {
1599                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1600                                         $result = false;
1601                                         return $result;
1602                                 }
1603                                 wfDebug( " accepts gzip\n" );
1604                                 $result = true;
1605                         }
1606                 }
1607         }
1608         return $result;
1609 }
1610
1611 /**
1612  * Obtain the offset and limit values from the request string;
1613  * used in special pages
1614  *
1615  * @param $deflimit Int default limit if none supplied
1616  * @param $optionname String Name of a user preference to check against
1617  * @return array
1618  *
1619  */
1620 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1621         global $wgRequest;
1622         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1623 }
1624
1625 /**
1626  * Escapes the given text so that it may be output using addWikiText()
1627  * without any linking, formatting, etc. making its way through. This
1628  * is achieved by substituting certain characters with HTML entities.
1629  * As required by the callers, <nowiki> is not used.
1630  *
1631  * @param $text String: text to be escaped
1632  * @return String
1633  */
1634 function wfEscapeWikiText( $text ) {
1635         $text = strtr( "\n$text", array(
1636                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1637                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1638                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1639                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1640                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1641                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1642         ) );
1643         return substr( $text, 1 );
1644 }
1645
1646 /**
1647  * Get the current unix timetstamp with microseconds.  Useful for profiling
1648  * @return Float
1649  */
1650 function wfTime() {
1651         return microtime( true );
1652 }
1653
1654 /**
1655  * Sets dest to source and returns the original value of dest
1656  * If source is NULL, it just returns the value, it doesn't set the variable
1657  * If force is true, it will set the value even if source is NULL
1658  *
1659  * @param $dest Mixed
1660  * @param $source Mixed
1661  * @param $force Bool
1662  * @return Mixed
1663  */
1664 function wfSetVar( &$dest, $source, $force = false ) {
1665         $temp = $dest;
1666         if ( !is_null( $source ) || $force ) {
1667                 $dest = $source;
1668         }
1669         return $temp;
1670 }
1671
1672 /**
1673  * As for wfSetVar except setting a bit
1674  *
1675  * @param $dest Int
1676  * @param $bit Int
1677  * @param $state Bool
1678  */
1679 function wfSetBit( &$dest, $bit, $state = true ) {
1680         $temp = (bool)( $dest & $bit );
1681         if ( !is_null( $state ) ) {
1682                 if ( $state ) {
1683                         $dest |= $bit;
1684                 } else {
1685                         $dest &= ~$bit;
1686                 }
1687         }
1688         return $temp;
1689 }
1690
1691 /**
1692  * Windows-compatible version of escapeshellarg()
1693  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1694  * function puts single quotes in regardless of OS.
1695  *
1696  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1697  * earlier distro releases of PHP)
1698  *
1699  * @param varargs
1700  * @return String
1701  */
1702 function wfEscapeShellArg( ) {
1703         wfInitShellLocale();
1704
1705         $args = func_get_args();
1706         $first = true;
1707         $retVal = '';
1708         foreach ( $args as $arg ) {
1709                 if ( !$first ) {
1710                         $retVal .= ' ';
1711                 } else {
1712                         $first = false;
1713                 }
1714
1715                 if ( wfIsWindows() ) {
1716                         // Escaping for an MSVC-style command line parser and CMD.EXE
1717                         // Refs:
1718                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1719                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1720                         //  * Bug #13518
1721                         //  * CR r63214
1722                         // Double the backslashes before any double quotes. Escape the double quotes.
1723                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1724                         $arg = '';
1725                         $iteration = 0;
1726                         foreach ( $tokens as $token ) {
1727                                 if ( $iteration % 2 == 1 ) {
1728                                         // Delimiter, a double quote preceded by zero or more slashes
1729                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1730                                 } elseif ( $iteration % 4 == 2 ) {
1731                                         // ^ in $token will be outside quotes, need to be escaped
1732                                         $arg .= str_replace( '^', '^^', $token );
1733                                 } else { // $iteration % 4 == 0
1734                                         // ^ in $token will appear inside double quotes, so leave as is
1735                                         $arg .= $token;
1736                                 }
1737                                 $iteration++;
1738                         }
1739                         // Double the backslashes before the end of the string, because
1740                         // we will soon add a quote
1741                         $m = array();
1742                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1743                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1744                         }
1745
1746                         // Add surrounding quotes
1747                         $retVal .= '"' . $arg . '"';
1748                 } else {
1749                         $retVal .= escapeshellarg( $arg );
1750                 }
1751         }
1752         return $retVal;
1753 }
1754
1755 /**
1756  * wfMerge attempts to merge differences between three texts.
1757  * Returns true for a clean merge and false for failure or a conflict.
1758  *
1759  * @param $old String
1760  * @param $mine String
1761  * @param $yours String
1762  * @param $result String
1763  * @return Bool
1764  */
1765 function wfMerge( $old, $mine, $yours, &$result ) {
1766         global $wgDiff3;
1767
1768         # This check may also protect against code injection in
1769         # case of broken installations.
1770         wfSuppressWarnings();
1771         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1772         wfRestoreWarnings();
1773
1774         if( !$haveDiff3 ) {
1775                 wfDebug( "diff3 not found\n" );
1776                 return false;
1777         }
1778
1779         # Make temporary files
1780         $td = wfTempDir();
1781         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1782         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1783         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1784
1785         fwrite( $oldtextFile, $old );
1786         fclose( $oldtextFile );
1787         fwrite( $mytextFile, $mine );
1788         fclose( $mytextFile );
1789         fwrite( $yourtextFile, $yours );
1790         fclose( $yourtextFile );
1791
1792         # Check for a conflict
1793         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1794                 wfEscapeShellArg( $mytextName ) . ' ' .
1795                 wfEscapeShellArg( $oldtextName ) . ' ' .
1796                 wfEscapeShellArg( $yourtextName );
1797         $handle = popen( $cmd, 'r' );
1798
1799         if( fgets( $handle, 1024 ) ) {
1800                 $conflict = true;
1801         } else {
1802                 $conflict = false;
1803         }
1804         pclose( $handle );
1805
1806         # Merge differences
1807         $cmd = $wgDiff3 . ' -a -e --merge ' .
1808                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1809         $handle = popen( $cmd, 'r' );
1810         $result = '';
1811         do {
1812                 $data = fread( $handle, 8192 );
1813                 if ( strlen( $data ) == 0 ) {
1814                         break;
1815                 }
1816                 $result .= $data;
1817         } while ( true );
1818         pclose( $handle );
1819         unlink( $mytextName );
1820         unlink( $oldtextName );
1821         unlink( $yourtextName );
1822
1823         if ( $result === '' && $old !== '' && !$conflict ) {
1824                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1825                 $conflict = true;
1826         }
1827         return !$conflict;
1828 }
1829
1830 /**
1831  * Returns unified plain-text diff of two texts.
1832  * Useful for machine processing of diffs.
1833  *
1834  * @param $before String: the text before the changes.
1835  * @param $after String: the text after the changes.
1836  * @param $params String: command-line options for the diff command.
1837  * @return String: unified diff of $before and $after
1838  */
1839 function wfDiff( $before, $after, $params = '-u' ) {
1840         if ( $before == $after ) {
1841                 return '';
1842         }
1843
1844         global $wgDiff;
1845         wfSuppressWarnings();
1846         $haveDiff = $wgDiff && file_exists( $wgDiff );
1847         wfRestoreWarnings();
1848
1849         # This check may also protect against code injection in
1850         # case of broken installations.
1851         if( !$haveDiff ) {
1852                 wfDebug( "diff executable not found\n" );
1853                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1854                 $format = new UnifiedDiffFormatter();
1855                 return $format->format( $diffs );
1856         }
1857
1858         # Make temporary files
1859         $td = wfTempDir();
1860         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1861         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1862
1863         fwrite( $oldtextFile, $before );
1864         fclose( $oldtextFile );
1865         fwrite( $newtextFile, $after );
1866         fclose( $newtextFile );
1867
1868         // Get the diff of the two files
1869         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1870
1871         $h = popen( $cmd, 'r' );
1872
1873         $diff = '';
1874
1875         do {
1876                 $data = fread( $h, 8192 );
1877                 if ( strlen( $data ) == 0 ) {
1878                         break;
1879                 }
1880                 $diff .= $data;
1881         } while ( true );
1882
1883         // Clean up
1884         pclose( $h );
1885         unlink( $oldtextName );
1886         unlink( $newtextName );
1887
1888         // Kill the --- and +++ lines. They're not useful.
1889         $diff_lines = explode( "\n", $diff );
1890         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1891                 unset( $diff_lines[0] );
1892         }
1893         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1894                 unset( $diff_lines[1] );
1895         }
1896
1897         $diff = implode( "\n", $diff_lines );
1898
1899         return $diff;
1900 }
1901
1902 /**
1903  * A wrapper around the PHP function var_export().
1904  * Either print it or add it to the regular output ($wgOut).
1905  *
1906  * @param $var A PHP variable to dump.
1907  */
1908 function wfVarDump( $var ) {
1909         global $wgOut;
1910         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1911         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1912                 print $s;
1913         } else {
1914                 $wgOut->addHTML( $s );
1915         }
1916 }
1917
1918 /**
1919  * Provide a simple HTTP error.
1920  *
1921  * @param $code Int|String
1922  * @param $label String
1923  * @param $desc String
1924  */
1925 function wfHttpError( $code, $label, $desc ) {
1926         global $wgOut;
1927         $wgOut->disable();
1928         header( "HTTP/1.0 $code $label" );
1929         header( "Status: $code $label" );
1930         $wgOut->sendCacheControl();
1931
1932         header( 'Content-type: text/html; charset=utf-8' );
1933         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1934                 '<html><head><title>' .
1935                 htmlspecialchars( $label ) .
1936                 '</title></head><body><h1>' .
1937                 htmlspecialchars( $label ) .
1938                 '</h1><p>' .
1939                 nl2br( htmlspecialchars( $desc ) ) .
1940                 "</p></body></html>\n";
1941 }
1942
1943 /**
1944  * Clear away any user-level output buffers, discarding contents.
1945  *
1946  * Suitable for 'starting afresh', for instance when streaming
1947  * relatively large amounts of data without buffering, or wanting to
1948  * output image files without ob_gzhandler's compression.
1949  *
1950  * The optional $resetGzipEncoding parameter controls suppression of
1951  * the Content-Encoding header sent by ob_gzhandler; by default it
1952  * is left. See comments for wfClearOutputBuffers() for why it would
1953  * be used.
1954  *
1955  * Note that some PHP configuration options may add output buffer
1956  * layers which cannot be removed; these are left in place.
1957  *
1958  * @param $resetGzipEncoding Bool
1959  */
1960 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1961         if( $resetGzipEncoding ) {
1962                 // Suppress Content-Encoding and Content-Length
1963                 // headers from 1.10+s wfOutputHandler
1964                 global $wgDisableOutputCompression;
1965                 $wgDisableOutputCompression = true;
1966         }
1967         while( $status = ob_get_status() ) {
1968                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1969                         // Probably from zlib.output_compression or other
1970                         // PHP-internal setting which can't be removed.
1971                         //
1972                         // Give up, and hope the result doesn't break
1973                         // output behavior.
1974                         break;
1975                 }
1976                 if( !ob_end_clean() ) {
1977                         // Could not remove output buffer handler; abort now
1978                         // to avoid getting in some kind of infinite loop.
1979                         break;
1980                 }
1981                 if( $resetGzipEncoding ) {
1982                         if( $status['name'] == 'ob_gzhandler' ) {
1983                                 // Reset the 'Content-Encoding' field set by this handler
1984                                 // so we can start fresh.
1985                                 if ( function_exists( 'header_remove' ) ) {
1986                                         // Available since PHP 5.3.0
1987                                         header_remove( 'Content-Encoding' );
1988                                 } else {
1989                                         // We need to provide a valid content-coding. See bug 28069
1990                                         header( 'Content-Encoding: identity' );
1991                                 }
1992                                 break;
1993                         }
1994                 }
1995         }
1996 }
1997
1998 /**
1999  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2000  *
2001  * Clear away output buffers, but keep the Content-Encoding header
2002  * produced by ob_gzhandler, if any.
2003  *
2004  * This should be used for HTTP 304 responses, where you need to
2005  * preserve the Content-Encoding header of the real result, but
2006  * also need to suppress the output of ob_gzhandler to keep to spec
2007  * and avoid breaking Firefox in rare cases where the headers and
2008  * body are broken over two packets.
2009  */
2010 function wfClearOutputBuffers() {
2011         wfResetOutputBuffers( false );
2012 }
2013
2014 /**
2015  * Converts an Accept-* header into an array mapping string values to quality
2016  * factors
2017  *
2018  * @param $accept String
2019  * @param $def String default
2020  * @return Array
2021  */
2022 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2023         # No arg means accept anything (per HTTP spec)
2024         if( !$accept ) {
2025                 return array( $def => 1.0 );
2026         }
2027
2028         $prefs = array();
2029
2030         $parts = explode( ',', $accept );
2031
2032         foreach( $parts as $part ) {
2033                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2034                 $values = explode( ';', trim( $part ) );
2035                 $match = array();
2036                 if ( count( $values ) == 1 ) {
2037                         $prefs[$values[0]] = 1.0;
2038                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2039                         $prefs[$values[0]] = floatval( $match[1] );
2040                 }
2041         }
2042
2043         return $prefs;
2044 }
2045
2046 /**
2047  * Checks if a given MIME type matches any of the keys in the given
2048  * array. Basic wildcards are accepted in the array keys.
2049  *
2050  * Returns the matching MIME type (or wildcard) if a match, otherwise
2051  * NULL if no match.
2052  *
2053  * @param $type String
2054  * @param $avail Array
2055  * @return string
2056  * @private
2057  */
2058 function mimeTypeMatch( $type, $avail ) {
2059         if( array_key_exists( $type, $avail ) ) {
2060                 return $type;
2061         } else {
2062                 $parts = explode( '/', $type );
2063                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2064                         return $parts[0] . '/*';
2065                 } elseif( array_key_exists( '*/*', $avail ) ) {
2066                         return '*/*';
2067                 } else {
2068                         return null;
2069                 }
2070         }
2071 }
2072
2073 /**
2074  * Returns the 'best' match between a client's requested internet media types
2075  * and the server's list of available types. Each list should be an associative
2076  * array of type to preference (preference is a float between 0.0 and 1.0).
2077  * Wildcards in the types are acceptable.
2078  *
2079  * @param $cprefs Array: client's acceptable type list
2080  * @param $sprefs Array: server's offered types
2081  * @return string
2082  *
2083  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2084  * XXX: generalize to negotiate other stuff
2085  */
2086 function wfNegotiateType( $cprefs, $sprefs ) {
2087         $combine = array();
2088
2089         foreach( array_keys($sprefs) as $type ) {
2090                 $parts = explode( '/', $type );
2091                 if( $parts[1] != '*' ) {
2092                         $ckey = mimeTypeMatch( $type, $cprefs );
2093                         if( $ckey ) {
2094                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2095                         }
2096                 }
2097         }
2098
2099         foreach( array_keys( $cprefs ) as $type ) {
2100                 $parts = explode( '/', $type );
2101                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2102                         $skey = mimeTypeMatch( $type, $sprefs );
2103                         if( $skey ) {
2104                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2105                         }
2106                 }
2107         }
2108
2109         $bestq = 0;
2110         $besttype = null;
2111
2112         foreach( array_keys( $combine ) as $type ) {
2113                 if( $combine[$type] > $bestq ) {
2114                         $besttype = $type;
2115                         $bestq = $combine[$type];
2116                 }
2117         }
2118
2119         return $besttype;
2120 }
2121
2122 /**
2123  * Reference-counted warning suppression
2124  *
2125  * @param $end Bool
2126  */
2127 function wfSuppressWarnings( $end = false ) {
2128         static $suppressCount = 0;
2129         static $originalLevel = false;
2130
2131         if ( $end ) {
2132                 if ( $suppressCount ) {
2133                         --$suppressCount;
2134                         if ( !$suppressCount ) {
2135                                 error_reporting( $originalLevel );
2136                         }
2137                 }
2138         } else {
2139                 if ( !$suppressCount ) {
2140                         // E_DEPRECATED is undefined in PHP 5.2
2141                         if( !defined( 'E_DEPRECATED' ) ){
2142                                 define( 'E_DEPRECATED', 8192 );
2143                         }
2144                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2145                 }
2146                 ++$suppressCount;
2147         }
2148 }
2149
2150 /**
2151  * Restore error level to previous value
2152  */
2153 function wfRestoreWarnings() {
2154         wfSuppressWarnings( true );
2155 }
2156
2157 # Autodetect, convert and provide timestamps of various types
2158
2159 /**
2160  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2161  */
2162 define( 'TS_UNIX', 0 );
2163
2164 /**
2165  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2166  */
2167 define( 'TS_MW', 1 );
2168
2169 /**
2170  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2171  */
2172 define( 'TS_DB', 2 );
2173
2174 /**
2175  * RFC 2822 format, for E-mail and HTTP headers
2176  */
2177 define( 'TS_RFC2822', 3 );
2178
2179 /**
2180  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2181  *
2182  * This is used by Special:Export
2183  */
2184 define( 'TS_ISO_8601', 4 );
2185
2186 /**
2187  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2188  *
2189  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2190  *       DateTime tag and page 36 for the DateTimeOriginal and
2191  *       DateTimeDigitized tags.
2192  */
2193 define( 'TS_EXIF', 5 );
2194
2195 /**
2196  * Oracle format time.
2197  */
2198 define( 'TS_ORACLE', 6 );
2199
2200 /**
2201  * Postgres format time.
2202  */
2203 define( 'TS_POSTGRES', 7 );
2204
2205 /**
2206  * DB2 format time
2207  */
2208 define( 'TS_DB2', 8 );
2209
2210 /**
2211  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2212  */
2213 define( 'TS_ISO_8601_BASIC', 9 );
2214
2215 /**
2216  * Get a timestamp string in one of various formats
2217  *
2218  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2219  *                    function will autodetect which format is supplied and act
2220  *                    accordingly.
2221  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2222  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2223  */
2224 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2225         $uts = 0;
2226         $da = array();
2227         $strtime = '';
2228
2229         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2230                 $uts = time();
2231                 $strtime = "@$uts";
2232         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2233                 # TS_DB
2234         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2235                 # TS_EXIF
2236         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2237                 # TS_MW
2238         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2239                 # TS_UNIX
2240                 $uts = $ts;
2241                 $strtime = "@$ts"; // Undocumented?
2242         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2243                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2244                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2245                                 str_replace( '+00:00', 'UTC', $ts ) );
2246         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2247                 # TS_ISO_8601
2248         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2249                 #TS_ISO_8601_BASIC
2250         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2251                 # TS_POSTGRES
2252         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2253                 # TS_POSTGRES
2254         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2255                 # TS_DB2
2256         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2257                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2258                                                         '[ \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
2259                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2260                 # The regex is a superset of rfc2822 for readability
2261                 $strtime = strtok( $ts, ';' );
2262         } 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 ) ) {
2263                 # TS_RFC850
2264                 $strtime = $ts;
2265         } 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 ) ) {
2266                 # asctime
2267                 $strtime = $ts;
2268         } else {
2269                 # Bogus value...
2270                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2271
2272                 return false;
2273         }
2274
2275         static $formats = array(
2276                 TS_UNIX => 'U',
2277                 TS_MW => 'YmdHis',
2278                 TS_DB => 'Y-m-d H:i:s',
2279                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2280                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2281                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2282                 TS_RFC2822 => 'D, d M Y H:i:s',
2283                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2284                 TS_POSTGRES => 'Y-m-d H:i:s',
2285                 TS_DB2 => 'Y-m-d H:i:s',
2286         );
2287
2288         if ( !isset( $formats[$outputtype] ) ) {
2289                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2290         }
2291
2292         if ( function_exists( "date_create" ) ) {
2293                 if ( count( $da ) ) {
2294                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2295                                 (int)$da[1], (int)$da[2], (int)$da[3],
2296                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2297
2298                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2299                 } elseif ( $strtime ) {
2300                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2301                 } else {
2302                         return false;
2303                 }
2304
2305                 if ( !$d ) {
2306                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2307                         return false;
2308                 }
2309
2310                 $output = $d->format( $formats[$outputtype] );
2311         } else {
2312                 if ( count( $da ) ) {
2313                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2314                         // We may want to handle that explicitly at some point
2315                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2316                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2317                 } elseif ( $strtime ) {
2318                         $uts = strtotime( $strtime );
2319                 }
2320
2321                 if ( $uts === false ) {
2322                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2323                         return false;
2324                 }
2325
2326                 if ( TS_UNIX == $outputtype ) {
2327                         return $uts;
2328                 }
2329                 $output = gmdate( $formats[$outputtype], $uts );
2330         }
2331
2332         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2333                 $output .= ' GMT';
2334         }
2335
2336         return $output;
2337 }
2338
2339 /**
2340  * Return a formatted timestamp, or null if input is null.
2341  * For dealing with nullable timestamp columns in the database.
2342  *
2343  * @param $outputtype Integer
2344  * @param $ts String
2345  * @return String
2346  */
2347 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2348         if( is_null( $ts ) ) {
2349                 return null;
2350         } else {
2351                 return wfTimestamp( $outputtype, $ts );
2352         }
2353 }
2354
2355 /**
2356  * Convenience function; returns MediaWiki timestamp for the present time.
2357  *
2358  * @return string
2359  */
2360 function wfTimestampNow() {
2361         # return NOW
2362         return wfTimestamp( TS_MW, time() );
2363 }
2364
2365 /**
2366  * Check if the operating system is Windows
2367  *
2368  * @return Bool: true if it's Windows, False otherwise.
2369  */
2370 function wfIsWindows() {
2371         static $isWindows = null;
2372         if ( $isWindows === null ) {
2373                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2374         }
2375         return $isWindows;
2376 }
2377
2378 /**
2379  * Check if we are running under HipHop
2380  *
2381  * @return Bool
2382  */
2383 function wfIsHipHop() {
2384         return function_exists( 'hphp_thread_set_warmup_enabled' );
2385 }
2386
2387 /**
2388  * Swap two variables
2389  *
2390  * @param $x Mixed
2391  * @param $y Mixed
2392  */
2393 function swap( &$x, &$y ) {
2394         $z = $x;
2395         $x = $y;
2396         $y = $z;
2397 }
2398
2399 /**
2400  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2401  * TEMP environment variables are then checked in sequence, and if none are set
2402  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2403  * or C:\Windows\Temp for Windows and hope for the best.
2404  * It is common to call it with tempnam().
2405  *
2406  * NOTE: When possible, use instead the tmpfile() function to create
2407  * temporary files to avoid race conditions on file creation, etc.
2408  *
2409  * @return String
2410  */
2411 function wfTempDir() {
2412         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2413                 $tmp = getenv( $var );
2414                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2415                         return $tmp;
2416                 }
2417         }
2418         if( function_exists( 'sys_get_temp_dir' ) ) {
2419                 return sys_get_temp_dir();
2420         }
2421         # Usual defaults
2422         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2423 }
2424
2425 /**
2426  * Make directory, and make all parent directories if they don't exist
2427  *
2428  * @param $dir String: full path to directory to create
2429  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2430  * @param $caller String: optional caller param for debugging.
2431  * @return bool
2432  */
2433 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2434         global $wgDirectoryMode;
2435
2436         if ( !is_null( $caller ) ) {
2437                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2438         }
2439
2440         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2441                 return true;
2442         }
2443
2444         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2445
2446         if ( is_null( $mode ) ) {
2447                 $mode = $wgDirectoryMode;
2448         }
2449
2450         // Turn off the normal warning, we're doing our own below
2451         wfSuppressWarnings();
2452         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2453         wfRestoreWarnings();
2454
2455         if( !$ok ) {
2456                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2457                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2458         }
2459         return $ok;
2460 }
2461
2462 /**
2463  * Increment a statistics counter
2464  *
2465  * @param $key String
2466  * @param $count Int
2467  */
2468 function wfIncrStats( $key, $count = 1 ) {
2469         global $wgStatsMethod;
2470
2471         $count = intval( $count );
2472
2473         if( $wgStatsMethod == 'udp' ) {
2474                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2475                 static $socket;
2476
2477                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2478
2479                 if ( !$socket ) {
2480                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2481                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2482                         socket_sendto(
2483                                 $socket,
2484                                 $statline,
2485                                 strlen( $statline ),
2486                                 0,
2487                                 $wgUDPProfilerHost,
2488                                 $wgUDPProfilerPort
2489                         );
2490                 }
2491                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2492                 wfSuppressWarnings();
2493                 socket_sendto(
2494                         $socket,
2495                         $statline,
2496                         strlen( $statline ),
2497                         0,
2498                         $wgUDPProfilerHost,
2499                         $wgUDPProfilerPort
2500                 );
2501                 wfRestoreWarnings();
2502         } elseif( $wgStatsMethod == 'cache' ) {
2503                 global $wgMemc;
2504                 $key = wfMemcKey( 'stats', $key );
2505                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2506                         $wgMemc->add( $key, $count );
2507                 }
2508         } else {
2509                 // Disabled
2510         }
2511 }
2512
2513 /**
2514  * @param $nr Mixed: the number to format
2515  * @param $acc Integer: the number of digits after the decimal point, default 2
2516  * @param $round Boolean: whether or not to round the value, default true
2517  * @return float
2518  */
2519 function wfPercent( $nr, $acc = 2, $round = true ) {
2520         $ret = sprintf( "%.${acc}f", $nr );
2521         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2522 }
2523
2524 /**
2525  * Find out whether or not a mixed variable exists in a string
2526  *
2527  * @param $needle String
2528  * @param $str String
2529  * @param $insensitive Boolean
2530  * @return Boolean
2531  */
2532 function in_string( $needle, $str, $insensitive = false ) {
2533         $func = 'strpos';
2534         if( $insensitive ) $func = 'stripos';
2535
2536         return $func( $str, $needle ) !== false;
2537 }
2538
2539 /**
2540  * Make a list item, used by various special pages
2541  *
2542  * @param $page String Page link
2543  * @param $details String Text between brackets
2544  * @param $oppositedm Boolean   Add the direction mark opposite to your
2545  *                                                              language, to display text properly
2546  * @return String
2547  */
2548 function wfSpecialList( $page, $details, $oppositedm = true ) {
2549         global $wgLang;
2550         $dirmark = ( $oppositedm ? $wgLang->getDirMark( true ) : '' ) .
2551                 $wgLang->getDirMark();
2552         $details = $details ? $dirmark . " ($details)" : '';
2553         return $page . $details;
2554 }
2555
2556 /**
2557  * Safety wrapper around ini_get() for boolean settings.
2558  * The values returned from ini_get() are pre-normalized for settings
2559  * set via php.ini or php_flag/php_admin_flag... but *not*
2560  * for those set via php_value/php_admin_value.
2561  *
2562  * It's fairly common for people to use php_value instead of php_flag,
2563  * which can leave you with an 'off' setting giving a false positive
2564  * for code that just takes the ini_get() return value as a boolean.
2565  *
2566  * To make things extra interesting, setting via php_value accepts
2567  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2568  * Unrecognized values go false... again opposite PHP's own coercion
2569  * from string to bool.
2570  *
2571  * Luckily, 'properly' set settings will always come back as '0' or '1',
2572  * so we only have to worry about them and the 'improper' settings.
2573  *
2574  * I frickin' hate PHP... :P
2575  *
2576  * @param $setting String
2577  * @return Bool
2578  */
2579 function wfIniGetBool( $setting ) {
2580         $val = ini_get( $setting );
2581         // 'on' and 'true' can't have whitespace around them, but '1' can.
2582         return strtolower( $val ) == 'on'
2583                 || strtolower( $val ) == 'true'
2584                 || strtolower( $val ) == 'yes'
2585                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2586 }
2587
2588 /**
2589  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2590  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2591  *
2592  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2593  *                          should be omitted
2594  * @param $fileName String Name of the library, if not $extension.suffix
2595  * @return Bool - Whether or not the extension is loaded
2596  */
2597 function wfDl( $extension, $fileName = null ) {
2598         if( extension_loaded( $extension ) ) {
2599                 return true;
2600         }
2601
2602         $canDl = false;
2603         $sapi = php_sapi_name();
2604         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2605                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2606         {
2607                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2608                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2609         }
2610
2611         if( $canDl ) {
2612                 $fileName = $fileName ? $fileName : $extension;
2613                 if( wfIsWindows() ) {
2614                         $fileName = 'php_' . $fileName;
2615                 }
2616                 wfSuppressWarnings();
2617                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2618                 wfRestoreWarnings();
2619         }
2620         return extension_loaded( $extension );
2621 }
2622
2623 /**
2624  * Execute a shell command, with time and memory limits mirrored from the PHP
2625  * configuration if supported.
2626  * @param $cmd String Command line, properly escaped for shell.
2627  * @param &$retval optional, will receive the program's exit code.
2628  *                 (non-zero is usually failure)
2629  * @param $environ Array optional environment variables which should be
2630  *                 added to the executed command environment.
2631  * @return collected stdout as a string (trailing newlines stripped)
2632  */
2633 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2634         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2635
2636         static $disabled;
2637         if ( is_null( $disabled ) ) {
2638                 $disabled = false;
2639                 if( wfIniGetBool( 'safe_mode' ) ) {
2640                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2641                         $disabled = 'safemode';
2642                 } else {
2643                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2644                         $functions = array_map( 'trim', $functions );
2645                         $functions = array_map( 'strtolower', $functions );
2646                         if ( in_array( 'passthru', $functions ) ) {
2647                                 wfDebug( "passthru is in disabled_functions\n" );
2648                                 $disabled = 'passthru';
2649                         }
2650                 }
2651         }
2652         if ( $disabled ) {
2653                 $retval = 1;
2654                 return $disabled == 'safemode' ?
2655                         'Unable to run external programs in safe mode.' :
2656                         'Unable to run external programs, passthru() is disabled.';
2657         }
2658
2659         wfInitShellLocale();
2660
2661         $envcmd = '';
2662         foreach( $environ as $k => $v ) {
2663                 if ( wfIsWindows() ) {
2664                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2665                          * appear in the environment variable, so we must use carat escaping as documented in
2666                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2667                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2668                          * are listed there but doesn't appear to need it.
2669                          */
2670                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2671                 } else {
2672                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2673                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2674                          */
2675                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2676                 }
2677         }
2678         $cmd = $envcmd . $cmd;
2679
2680         if ( wfIsWindows() ) {
2681                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2682                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2683                 {
2684                         # Hack to work around PHP's flawed invocation of cmd.exe
2685                         # http://news.php.net/php.internals/21796
2686                         # Windows 9x doesn't accept any kind of quotes
2687                         $cmd = '"' . $cmd . '"';
2688                 }
2689         } elseif ( php_uname( 's' ) == 'Linux' ) {
2690                 $time = intval( $wgMaxShellTime );
2691                 $mem = intval( $wgMaxShellMemory );
2692                 $filesize = intval( $wgMaxShellFileSize );
2693
2694                 if ( $time > 0 && $mem > 0 ) {
2695                         $script = "$IP/bin/ulimit4.sh";
2696                         if ( is_executable( $script ) ) {
2697                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2698                         }
2699                 }
2700         }
2701         wfDebug( "wfShellExec: $cmd\n" );
2702
2703         $retval = 1; // error by default?
2704         ob_start();
2705         passthru( $cmd, $retval );
2706         $output = ob_get_contents();
2707         ob_end_clean();
2708
2709         if ( $retval == 127 ) {
2710                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2711         }
2712         return $output;
2713 }
2714
2715 /**
2716  * Workaround for http://bugs.php.net/bug.php?id=45132
2717  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2718  */
2719 function wfInitShellLocale() {
2720         static $done = false;
2721         if ( $done ) {
2722                 return;
2723         }
2724         $done = true;
2725         global $wgShellLocale;
2726         if ( !wfIniGetBool( 'safe_mode' ) ) {
2727                 putenv( "LC_CTYPE=$wgShellLocale" );
2728                 setlocale( LC_CTYPE, $wgShellLocale );
2729         }
2730 }
2731
2732 /**
2733  * This function works like "use VERSION" in Perl, the program will die with a
2734  * backtrace if the current version of PHP is less than the version provided
2735  *
2736  * This is useful for extensions which due to their nature are not kept in sync
2737  * with releases, and might depend on other versions of PHP than the main code
2738  *
2739  * Note: PHP might die due to parsing errors in some cases before it ever
2740  *       manages to call this function, such is life
2741  *
2742  * @see perldoc -f use
2743  *
2744  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2745  *                 a float
2746  */
2747 function wfUsePHP( $req_ver ) {
2748         $php_ver = PHP_VERSION;
2749
2750         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2751                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2752         }
2753 }
2754
2755 /**
2756  * This function works like "use VERSION" in Perl except it checks the version
2757  * of MediaWiki, the program will die with a backtrace if the current version
2758  * of MediaWiki is less than the version provided.
2759  *
2760  * This is useful for extensions which due to their nature are not kept in sync
2761  * with releases
2762  *
2763  * @see perldoc -f use
2764  *
2765  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2766  *                 a float
2767  */
2768 function wfUseMW( $req_ver ) {
2769         global $wgVersion;
2770
2771         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2772                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2773         }
2774 }
2775
2776 /**
2777  * Return the final portion of a pathname.
2778  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2779  * http://bugs.php.net/bug.php?id=33898
2780  *
2781  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2782  * We'll consider it so always, as we don't want \s in our Unix paths either.
2783  *
2784  * @param $path String
2785  * @param $suffix String: to remove if present
2786  * @return String
2787  */
2788 function wfBaseName( $path, $suffix = '' ) {
2789         $encSuffix = ( $suffix == '' )
2790                 ? ''
2791                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2792         $matches = array();
2793         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2794                 return $matches[1];
2795         } else {
2796                 return '';
2797         }
2798 }
2799
2800 /**
2801  * Generate a relative path name to the given file.
2802  * May explode on non-matching case-insensitive paths,
2803  * funky symlinks, etc.
2804  *
2805  * @param $path String: absolute destination path including target filename
2806  * @param $from String: Absolute source path, directory only
2807  * @return String
2808  */
2809 function wfRelativePath( $path, $from ) {
2810         // Normalize mixed input on Windows...
2811         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2812         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2813
2814         // Trim trailing slashes -- fix for drive root
2815         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2816         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2817
2818         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2819         $against = explode( DIRECTORY_SEPARATOR, $from );
2820
2821         if( $pieces[0] !== $against[0] ) {
2822                 // Non-matching Windows drive letters?
2823                 // Return a full path.
2824                 return $path;
2825         }
2826
2827         // Trim off common prefix
2828         while( count( $pieces ) && count( $against )
2829                 && $pieces[0] == $against[0] ) {
2830                 array_shift( $pieces );
2831                 array_shift( $against );
2832         }
2833
2834         // relative dots to bump us to the parent
2835         while( count( $against ) ) {
2836                 array_unshift( $pieces, '..' );
2837                 array_shift( $against );
2838         }
2839
2840         array_push( $pieces, wfBaseName( $path ) );
2841
2842         return implode( DIRECTORY_SEPARATOR, $pieces );
2843 }
2844
2845 /**
2846  * Do any deferred updates and clear the list
2847  *
2848  * @param $commit String: set to 'commit' to commit after every update to
2849  *                prevent lock contention
2850  */
2851 function wfDoUpdates( $commit = '' ) {
2852         global $wgDeferredUpdateList;
2853
2854         wfProfileIn( __METHOD__ );
2855
2856         // No need to get master connections in case of empty updates array
2857         if ( !count( $wgDeferredUpdateList ) ) {
2858                 wfProfileOut( __METHOD__ );
2859                 return;
2860         }
2861
2862         $doCommit = $commit == 'commit';
2863         if ( $doCommit ) {
2864                 $dbw = wfGetDB( DB_MASTER );
2865         }
2866
2867         foreach ( $wgDeferredUpdateList as $update ) {
2868                 $update->doUpdate();
2869
2870                 if ( $doCommit && $dbw->trxLevel() ) {
2871                         $dbw->commit();
2872                 }
2873         }
2874
2875         $wgDeferredUpdateList = array();
2876         wfProfileOut( __METHOD__ );
2877 }
2878
2879 /**
2880  * Convert an arbitrarily-long digit string from one numeric base
2881  * to another, optionally zero-padding to a minimum column width.
2882  *
2883  * Supports base 2 through 36; digit values 10-36 are represented
2884  * as lowercase letters a-z. Input is case-insensitive.
2885  *
2886  * @param $input String: of digits
2887  * @param $sourceBase Integer: 2-36
2888  * @param $destBase Integer: 2-36
2889  * @param $pad Integer: 1 or greater
2890  * @param $lowercase Boolean
2891  * @return String or false on invalid input
2892  */
2893 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2894         $input = strval( $input );
2895         if( $sourceBase < 2 ||
2896                 $sourceBase > 36 ||
2897                 $destBase < 2 ||
2898                 $destBase > 36 ||
2899                 $pad < 1 ||
2900                 $sourceBase != intval( $sourceBase ) ||
2901                 $destBase != intval( $destBase ) ||
2902                 $pad != intval( $pad ) ||
2903                 !is_string( $input ) ||
2904                 $input == '' ) {
2905                 return false;
2906         }
2907         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2908         $inDigits = array();
2909         $outChars = '';
2910
2911         // Decode and validate input string
2912         $input = strtolower( $input );
2913         for( $i = 0; $i < strlen( $input ); $i++ ) {
2914                 $n = strpos( $digitChars, $input[$i] );
2915                 if( $n === false || $n > $sourceBase ) {
2916                         return false;
2917                 }
2918                 $inDigits[] = $n;
2919         }
2920
2921         // Iterate over the input, modulo-ing out an output digit
2922         // at a time until input is gone.
2923         while( count( $inDigits ) ) {
2924                 $work = 0;
2925                 $workDigits = array();
2926
2927                 // Long division...
2928                 foreach( $inDigits as $digit ) {
2929                         $work *= $sourceBase;
2930                         $work += $digit;
2931
2932                         if( $work < $destBase ) {
2933                                 // Gonna need to pull another digit.
2934                                 if( count( $workDigits ) ) {
2935                                         // Avoid zero-padding; this lets us find
2936                                         // the end of the input very easily when
2937                                         // length drops to zero.
2938                                         $workDigits[] = 0;
2939                                 }
2940                         } else {
2941                                 // Finally! Actual division!
2942                                 $workDigits[] = intval( $work / $destBase );
2943
2944                                 // Isn't it annoying that most programming languages
2945                                 // don't have a single divide-and-remainder operator,
2946                                 // even though the CPU implements it that way?
2947                                 $work = $work % $destBase;
2948                         }
2949                 }
2950
2951                 // All that division leaves us with a remainder,
2952                 // which is conveniently our next output digit.
2953                 $outChars .= $digitChars[$work];
2954
2955                 // And we continue!
2956                 $inDigits = $workDigits;
2957         }
2958
2959         while( strlen( $outChars ) < $pad ) {
2960                 $outChars .= '0';
2961         }
2962
2963         return strrev( $outChars );
2964 }
2965
2966 /**
2967  * Create an object with a given name and an array of construct parameters
2968  *
2969  * @param $name String
2970  * @param $p Array: parameters
2971  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
2972  */
2973 function wfCreateObject( $name, $p ) {
2974         wfDeprecated( __FUNCTION__ );
2975         return MWFunction::newObj( $name, $p );
2976 }
2977
2978 function wfHttpOnlySafe() {
2979         global $wgHttpOnlyBlacklist;
2980
2981         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2982                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2983                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2984                                 return false;
2985                         }
2986                 }
2987         }
2988
2989         return true;
2990 }
2991
2992 /**
2993  * Initialise php session
2994  *
2995  * @param $sessionId Bool
2996  */
2997 function wfSetupSession( $sessionId = false ) {
2998         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
2999                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3000         if( $wgSessionsInMemcached ) {
3001                 if ( !defined( 'MW_COMPILED' ) ) {
3002                         global $IP;
3003                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3004                 }
3005                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3006                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3007
3008                 // It's necessary to register a shutdown function to call session_write_close(),
3009                 // because by the time the request shutdown function for the session module is
3010                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3011                 // this way are called before object destruction.
3012                 register_shutdown_function( 'memsess_write_close' );
3013         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3014                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3015                 # hasn't already been set to the desired value (that causes errors)
3016                 ini_set( 'session.save_handler', $wgSessionHandler );
3017         }
3018         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3019         wfDebugLog( 'cookie',
3020                 'session_set_cookie_params: "' . implode( '", "',
3021                         array(
3022                                 0,
3023                                 $wgCookiePath,
3024                                 $wgCookieDomain,
3025                                 $wgCookieSecure,
3026                                 $httpOnlySafe ) ) . '"' );
3027         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3028         session_cache_limiter( 'private, must-revalidate' );
3029         if ( $sessionId ) {
3030                 session_id( $sessionId );
3031         }
3032         wfSuppressWarnings();
3033         session_start();
3034         wfRestoreWarnings();
3035 }
3036
3037 /**
3038  * Get an object from the precompiled serialized directory
3039  *
3040  * @param $name String
3041  * @return Mixed: the variable on success, false on failure
3042  */
3043 function wfGetPrecompiledData( $name ) {
3044         global $IP;
3045
3046         $file = "$IP/serialized/$name";
3047         if ( file_exists( $file ) ) {
3048                 $blob = file_get_contents( $file );
3049                 if ( $blob ) {
3050                         return unserialize( $blob );
3051                 }
3052         }
3053         return false;
3054 }
3055
3056 /**
3057  * Get a cache key
3058  *
3059  * @param varargs
3060  * @return String
3061  */
3062 function wfMemcKey( /*... */ ) {
3063         $args = func_get_args();
3064         $key = wfWikiID() . ':' . implode( ':', $args );
3065         $key = str_replace( ' ', '_', $key );
3066         return $key;
3067 }
3068
3069 /**
3070  * Get a cache key for a foreign DB
3071  *
3072  * @param $db String
3073  * @param $prefix String
3074  * @param varargs String
3075  * @return String
3076  */
3077 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3078         $args = array_slice( func_get_args(), 2 );
3079         if ( $prefix ) {
3080                 $key = "$db-$prefix:" . implode( ':', $args );
3081         } else {
3082                 $key = $db . ':' . implode( ':', $args );
3083         }
3084         return $key;
3085 }
3086
3087 /**
3088  * Get an ASCII string identifying this wiki
3089  * This is used as a prefix in memcached keys
3090  *
3091  * @return String
3092  */
3093 function wfWikiID() {
3094         global $wgDBprefix, $wgDBname;
3095         if ( $wgDBprefix ) {
3096                 return "$wgDBname-$wgDBprefix";
3097         } else {
3098                 return $wgDBname;
3099         }
3100 }
3101
3102 /**
3103  * Split a wiki ID into DB name and table prefix
3104  *
3105  * @param $wiki String
3106  * @param $bits String
3107  */
3108 function wfSplitWikiID( $wiki ) {
3109         $bits = explode( '-', $wiki, 2 );
3110         if ( count( $bits ) < 2 ) {
3111                 $bits[] = '';
3112         }
3113         return $bits;
3114 }
3115
3116 /**
3117  * Get a Database object.
3118  *
3119  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3120  *            master (for write queries), DB_SLAVE for potentially lagged read
3121  *            queries, or an integer >= 0 for a particular server.
3122  *
3123  * @param $groups Mixed: query groups. An array of group names that this query
3124  *                belongs to. May contain a single string if the query is only
3125  *                in one group.
3126  *
3127  * @param $wiki String: the wiki ID, or false for the current wiki
3128  *
3129  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3130  * will always return the same object, unless the underlying connection or load
3131  * balancer is manually destroyed.
3132  *
3133  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3134  * updater to ensure that a proper database is being updated.
3135  *
3136  * @return DatabaseBase
3137  */
3138 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3139         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3140 }
3141
3142 /**
3143  * Get a load balancer object.
3144  *
3145  * @param $wiki String: wiki ID, or false for the current wiki
3146  * @return LoadBalancer
3147  */
3148 function wfGetLB( $wiki = false ) {
3149         return wfGetLBFactory()->getMainLB( $wiki );
3150 }
3151
3152 /**
3153  * Get the load balancer factory object
3154  *
3155  * @return LBFactory
3156  */
3157 function &wfGetLBFactory() {
3158         return LBFactory::singleton();
3159 }
3160
3161 /**
3162  * Find a file.
3163  * Shortcut for RepoGroup::singleton()->findFile()
3164  *
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  *
3189  * @param $title Title or String
3190  * @return File, or null if passed an invalid Title
3191  */
3192 function wfLocalFile( $title ) {
3193         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3194 }
3195
3196 /**
3197  * Should low-performance queries be disabled?
3198  *
3199  * @return Boolean
3200  * @codeCoverageIgnore
3201  */
3202 function wfQueriesMustScale() {
3203         global $wgMiserMode;
3204         return $wgMiserMode
3205                 || ( SiteStats::pages() > 100000
3206                 && SiteStats::edits() > 1000000
3207                 && SiteStats::users() > 10000 );
3208 }
3209
3210 /**
3211  * Get the path to a specified script file, respecting file
3212  * extensions; this is a wrapper around $wgScriptExtension etc.
3213  *
3214  * @param $script String: script filename, sans extension
3215  * @return String
3216  */
3217 function wfScript( $script = 'index' ) {
3218         global $wgScriptPath, $wgScriptExtension;
3219         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3220 }
3221
3222 /**
3223  * Get the script URL.
3224  *
3225  * @return script URL
3226  */
3227 function wfGetScriptUrl() {
3228         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3229                 #
3230                 # as it was called, minus the query string.
3231                 #
3232                 # Some sites use Apache rewrite rules to handle subdomains,
3233                 # and have PHP set up in a weird way that causes PHP_SELF
3234                 # to contain the rewritten URL instead of the one that the
3235                 # outside world sees.
3236                 #
3237                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3238                 # provides containing the "before" URL.
3239                 return $_SERVER['SCRIPT_NAME'];
3240         } else {
3241                 return $_SERVER['URL'];
3242         }
3243 }
3244
3245 /**
3246  * Convenience function converts boolean values into "true"
3247  * or "false" (string) values
3248  *
3249  * @param $value Boolean
3250  * @return String
3251  */
3252 function wfBoolToStr( $value ) {
3253         return $value ? 'true' : 'false';
3254 }
3255
3256 /**
3257  * Load an extension messages file
3258  *
3259  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3260  * @codeCoverageIgnore
3261  */
3262 function wfLoadExtensionMessages() {
3263         wfDeprecated( __FUNCTION__ );
3264 }
3265
3266 /**
3267  * Get a platform-independent path to the null file, e.g. /dev/null
3268  *
3269  * @return string
3270  */
3271 function wfGetNull() {
3272         return wfIsWindows()
3273                 ? 'NUL'
3274                 : '/dev/null';
3275 }
3276
3277 /**
3278  * Throws a warning that $function is deprecated
3279  *
3280  * @param $function String
3281  * @return null
3282  */
3283 function wfDeprecated( $function ) {
3284         static $functionsWarned = array();
3285         if ( !isset( $functionsWarned[$function] ) ) {
3286                 $functionsWarned[$function] = true;
3287                 wfWarn( "Use of $function is deprecated.", 2 );
3288         }
3289 }
3290
3291 /**
3292  * Send a warning either to the debug log or in a PHP error depending on
3293  * $wgDevelopmentWarnings
3294  *
3295  * @param $msg String: message to send
3296  * @param $callerOffset Integer: number of items to go back in the backtrace to
3297  *        find the correct caller (1 = function calling wfWarn, ...)
3298  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3299  *        is true
3300  */
3301 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3302         global $wgDevelopmentWarnings;
3303
3304         $callers = wfDebugBacktrace();
3305         if ( isset( $callers[$callerOffset + 1] ) ) {
3306                 $callerfunc = $callers[$callerOffset + 1];
3307                 $callerfile = $callers[$callerOffset];
3308                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3309                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3310                 } else {
3311                         $file = '(internal function)';
3312                 }
3313                 $func = '';
3314                 if ( isset( $callerfunc['class'] ) ) {
3315                         $func .= $callerfunc['class'] . '::';
3316                 }
3317                 if ( isset( $callerfunc['function'] ) ) {
3318                         $func .= $callerfunc['function'];
3319                 }
3320                 $msg .= " [Called from $func in $file]";
3321         }
3322
3323         if ( $wgDevelopmentWarnings ) {
3324                 trigger_error( $msg, $level );
3325         } else {
3326                 wfDebug( "$msg\n" );
3327         }
3328 }
3329
3330 /**
3331  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3332  * and waiting for it to go down, this waits for the slaves to catch up to the
3333  * master position. Use this when updating very large numbers of rows, as
3334  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3335  * a no-op if there are no slaves.
3336  *
3337  * @param $maxLag Integer (deprecated)
3338  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3339  * @return null
3340  */
3341 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3342         $lb = wfGetLB( $wiki );
3343         // bug 27975 - Don't try to wait for slaves if there are none
3344         // Prevents permission error when getting master position
3345         if ( $lb->getServerCount() > 1 ) {
3346                 $dbw = $lb->getConnection( DB_MASTER );
3347                 $pos = $dbw->getMasterPos();
3348                 $lb->waitForAll( $pos );
3349         }
3350 }
3351
3352 /**
3353  * Used to be used for outputting text in the installer/updater
3354  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3355  */
3356 function wfOut( $s ) {
3357         wfDeprecated( __METHOD__ );
3358         global $wgCommandLineMode;
3359         if ( $wgCommandLineMode ) {
3360                 echo $s;
3361         } else {
3362                 echo htmlspecialchars( $s );
3363         }
3364         flush();
3365 }
3366
3367 /**
3368  * Count down from $n to zero on the terminal, with a one-second pause
3369  * between showing each number. For use in command-line scripts.
3370  * @codeCoverageIgnore
3371  */
3372 function wfCountDown( $n ) {
3373         for ( $i = $n; $i >= 0; $i-- ) {
3374                 if ( $i != $n ) {
3375                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3376                 }
3377                 echo $i;
3378                 flush();
3379                 if ( $i ) {
3380                         sleep( 1 );
3381                 }
3382         }
3383         echo "\n";
3384 }
3385
3386 /**
3387  * Generate a random 32-character hexadecimal token.
3388  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3389  *              characters before hashing.
3390  * @return string
3391  * @codeCoverageIgnore
3392  */
3393 function wfGenerateToken( $salt = '' ) {
3394         $salt = serialize( $salt );
3395         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3396 }
3397
3398 /**
3399  * Replace all invalid characters with -
3400  *
3401  * @param $name Mixed: filename to process
3402  * @return String
3403  */
3404 function wfStripIllegalFilenameChars( $name ) {
3405         global $wgIllegalFileChars;
3406         $name = wfBaseName( $name );
3407         $name = preg_replace(
3408                 "/[^" . Title::legalChars() . "]" .
3409                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3410                         "/",
3411                 '-',
3412                 $name
3413         );
3414         return $name;
3415 }
3416
3417 /**
3418  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3419  *
3420  * @return Integer value memory was set to.
3421  */
3422 function wfMemoryLimit() {
3423         global $wgMemoryLimit;
3424         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3425         if( $memlimit != -1 ) {
3426                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3427                 if( $conflimit == -1 ) {
3428                         wfDebug( "Removing PHP's memory limit\n" );
3429                         wfSuppressWarnings();
3430                         ini_set( 'memory_limit', $conflimit );
3431                         wfRestoreWarnings();
3432                         return $conflimit;
3433                 } elseif ( $conflimit > $memlimit ) {
3434                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3435                         wfSuppressWarnings();
3436                         ini_set( 'memory_limit', $conflimit );
3437                         wfRestoreWarnings();
3438                         return $conflimit;
3439                 }
3440         }
3441         return $memlimit;
3442 }
3443
3444 /**
3445  * Converts shorthand byte notation to integer form
3446  *
3447  * @param $string String
3448  * @return Integer
3449  */
3450 function wfShorthandToInteger( $string = '' ) {
3451         $string = trim( $string );
3452         if( $string === '' ) {
3453                 return -1;
3454         }
3455         $last = $string[strlen( $string ) - 1];
3456         $val = intval( $string );
3457         switch( $last ) {
3458                 case 'g':
3459                 case 'G':
3460                         $val *= 1024;
3461                         // break intentionally missing
3462                 case 'm':
3463                 case 'M':
3464                         $val *= 1024;
3465                         // break intentionally missing
3466                 case 'k':
3467                 case 'K':
3468                         $val *= 1024;
3469         }
3470
3471         return $val;
3472 }
3473
3474 /**
3475  * Get the normalised IETF language tag
3476  * See unit test for examples.
3477  *
3478  * @param $code String: The language code.
3479  * @return $langCode String: The language code which complying with BCP 47 standards.
3480  */
3481 function wfBCP47( $code ) {
3482         $codeSegment = explode( '-', $code );
3483         $codeBCP = array();
3484         foreach ( $codeSegment as $segNo => $seg ) {
3485                 if ( count( $codeSegment ) > 0 ) {
3486                         // when previous segment is x, it is a private segment and should be lc
3487                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3488                                 $codeBCP[$segNo] = strtolower( $seg );
3489                         // ISO 3166 country code
3490                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3491                                 $codeBCP[$segNo] = strtoupper( $seg );
3492                         // ISO 15924 script code
3493                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3494                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3495                         // Use lowercase for other cases
3496                         } else {
3497                                 $codeBCP[$segNo] = strtolower( $seg );
3498                         }
3499                 } else {
3500                 // Use lowercase for single segment
3501                         $codeBCP[$segNo] = strtolower( $seg );
3502                 }
3503         }
3504         $langCode = implode( '-', $codeBCP );
3505         return $langCode;
3506 }
3507
3508 /**
3509  * Get a cache object.
3510  *
3511  * @param $inputType integer Cache type, one the the CACHE_* constants.
3512  * @return BagOStuff
3513  */
3514 function wfGetCache( $inputType ) {
3515         return ObjectCache::getInstance( $inputType );
3516 }
3517
3518 /**
3519  * Get the main cache object
3520  *
3521  * @return BagOStuff
3522  */
3523 function wfGetMainCache() {
3524         global $wgMainCacheType;
3525         return ObjectCache::getInstance( $wgMainCacheType );
3526 }
3527
3528 /**
3529  * Get the cache object used by the message cache
3530  *
3531  * @return BagOStuff
3532  */
3533 function wfGetMessageCacheStorage() {
3534         global $wgMessageCacheType;
3535         return ObjectCache::getInstance( $wgMessageCacheType );
3536 }
3537
3538 /**
3539  * Get the cache object used by the parser cache
3540  *
3541  * @return BagOStuff
3542  */
3543 function wfGetParserCacheStorage() {
3544         global $wgParserCacheType;
3545         return ObjectCache::getInstance( $wgParserCacheType );
3546 }
3547
3548 /**
3549  * Call hook functions defined in $wgHooks
3550  *
3551  * @param $event String: event name
3552  * @param $args Array: parameters passed to hook functions
3553  * @return Boolean
3554  */
3555 function wfRunHooks( $event, $args = array() ) {
3556         return Hooks::run( $event, $args );
3557 }