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  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 441  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 442  *
 443  * @todo this won't work with current-path-relative URLs
 444  * like "subdir/foo.html", etc.
 445  *
 446  * @param $url String: either fully-qualified or a local path + query
 447  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 448  * @return string Fully-qualified URL
 449  */
 450 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 451         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 452         $serverUrl = $wgServer;
 453         if ( $defaultProto === PROTO_CANONICAL ) {
 454                 $serverUrl = $wgCanonicalServer;
 455         }
 456         // Make $wgInternalServer fall back to $wgServer if not set
 457         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 458                 $serverUrl = $wgInternalServer;
 459         }
 460         if ( $defaultProto === PROTO_CURRENT ) {
 461                 $defaultProto = WebRequest::detectProtocol() . '://';
 462         }
 463
 464         // Analyze $serverUrl to obtain its protocol
 465         $bits = wfParseUrl( $serverUrl );
 466         $serverHasProto = $bits && $bits['scheme'] != '';
 467
 468         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 469                 if ( $serverHasProto ) {
 470                         $defaultProto = $bits['scheme'] . '://';
 471                 } else {
 472                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 473                         // Fall back to HTTP in this ridiculous case
 474                         $defaultProto = PROTO_HTTP;
 475                 }
 476         }
 477
 478         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 479
 480         if( substr( $url, 0, 2 ) == '//' ) {
 481                 return $defaultProtoWithoutSlashes . $url;
 482         } elseif( substr( $url, 0, 1 ) == '/' ) {
 483                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 484                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 485         } else {
 486                 return $url;
 487         }
 488 }
 489
 490 /**
 491  * Returns a regular expression of url protocols
 492  *
 493  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 494  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 495  * @return String
 496  */
 497 function wfUrlProtocols( $includeProtocolRelative = true ) {
 498         global $wgUrlProtocols;
 499
 500         // Cache return values separately based on $includeProtocolRelative
 501         static $withProtRel = null, $withoutProtRel = null;
 502         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 503         if ( !is_null( $cachedValue ) ) {
 504                 return $cachedValue;
 505         }
 506
 507         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 508         // with LocalSettings files from 1.5
 509         if ( is_array( $wgUrlProtocols ) ) {
 510                 $protocols = array();
 511                 foreach ( $wgUrlProtocols as $protocol ) {
 512                         // Filter out '//' if !$includeProtocolRelative
 513                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 514                                 $protocols[] = preg_quote( $protocol, '/' );
 515                         }
 516                 }
 517
 518                 $retval = implode( '|', $protocols );
 519         } else {
 520                 // Ignore $includeProtocolRelative in this case
 521                 // This case exists for pre-1.6 compatibility, and we can safely assume
 522                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 523                 // URLs weren't supported until 1.18
 524                 $retval = $wgUrlProtocols;
 525         }
 526
 527         // Cache return value
 528         if ( $includeProtocolRelative ) {
 529                 $withProtRel = $retval;
 530         } else {
 531                 $withoutProtRel = $retval;
 532         }
 533         return $retval;
 534 }
 535
 536 /**
 537  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 538  * you need a regex that matches all URL protocols but does not match protocol-
 539  * relative URLs
 540  * @return String
 541  */
 542 function wfUrlProtocolsWithoutProtRel() {
 543         return wfUrlProtocols( false );
 544 }
 545
 546 /**
 547  * parse_url() work-alike, but non-broken.  Differences:
 548  *
 549  * 1) Does not raise warnings on bad URLs (just returns false)
 550  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 551  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 552  *
 553  * @param $url String: a URL to parse
 554  * @return Array: bits of the URL in an associative array, per PHP docs
 555  */
 556 function wfParseUrl( $url ) {
 557         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 558
 559         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 560         // way to handle them is to just prepend 'http:' and strip the protocol out later
 561         $wasRelative = substr( $url, 0, 2 ) == '//';
 562         if ( $wasRelative ) {
 563                 $url = "http:$url";
 564         }
 565         wfSuppressWarnings();
 566         $bits = parse_url( $url );
 567         wfRestoreWarnings();
 568         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 569         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 570         if ( !$bits || !isset( $bits['scheme'] ) ) {
 571                 return false;
 572         }
 573
 574         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 575         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 576                 $bits['delimiter'] = '://';
 577         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 578                 $bits['delimiter'] = ':';
 579                 // parse_url detects for news: and mailto: the host part of an url as path
 580                 // We have to correct this wrong detection
 581                 if ( isset( $bits['path'] ) ) {
 582                         $bits['host'] = $bits['path'];
 583                         $bits['path'] = '';
 584                 }
 585         } else {
 586                 return false;
 587         }
 588
 589         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 590         if ( !isset( $bits['host'] ) ) {
 591                 $bits['host'] = '';
 592
 593                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 594                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 595                         $bits['path'] = '/' . $bits['path'];
 596                 }
 597         }
 598
 599         // If the URL was protocol-relative, fix scheme and delimiter
 600         if ( $wasRelative ) {
 601                 $bits['scheme'] = '';
 602                 $bits['delimiter'] = '//';
 603         }
 604         return $bits;
 605 }
 606
 607 /**
 608  * Make a URL index, appropriate for the el_index field of externallinks.
 609  *
 610  * @param $url String
 611  * @return String
 612  */
 613 function wfMakeUrlIndex( $url ) {
 614         $bits = wfParseUrl( $url );
 615
 616         // Reverse the labels in the hostname, convert to lower case
 617         // For emails reverse domainpart only
 618         if ( $bits['scheme'] == 'mailto' ) {
 619                 $mailparts = explode( '@', $bits['host'], 2 );
 620                 if ( count( $mailparts ) === 2 ) {
 621                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 622                 } else {
 623                         // No domain specified, don't mangle it
 624                         $domainpart = '';
 625                 }
 626                 $reversedHost = $domainpart . '@' . $mailparts[0];
 627         } else {
 628                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 629         }
 630         // Add an extra dot to the end
 631         // Why? Is it in wrong place in mailto links?
 632         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 633                 $reversedHost .= '.';
 634         }
 635         // Reconstruct the pseudo-URL
 636         $prot = $bits['scheme'];
 637         $index = $prot . $bits['delimiter'] . $reversedHost;
 638         // Leave out user and password. Add the port, path, query and fragment
 639         if ( isset( $bits['port'] ) ) {
 640                 $index .= ':' . $bits['port'];
 641         }
 642         if ( isset( $bits['path'] ) ) {
 643                 $index .= $bits['path'];
 644         } else {
 645                 $index .= '/';
 646         }
 647         if ( isset( $bits['query'] ) ) {
 648                 $index .= '?' . $bits['query'];
 649         }
 650         if ( isset( $bits['fragment'] ) ) {
 651                 $index .= '#' . $bits['fragment'];
 652         }
 653         return $index;
 654 }
 655
 656 /**
 657  * Check whether a given URL has a domain that occurs in a given set of domains
 658  * @param $url string URL
 659  * @param $domains array Array of domains (strings)
 660  * @return bool True if the host part of $url ends in one of the strings in $domains
 661  */
 662 function wfMatchesDomainList( $url, $domains ) {
 663         $bits = wfParseUrl( $url );
 664         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 665                 foreach ( (array)$domains as $domain ) {
 666                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 667                         // We should use something that interprets dots instead
 668                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 669                                 return true;
 670                         }
 671                 }
 672         }
 673         return false;
 674 }
 675
 676 /**
 677  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 678  * In normal operation this is a NOP.
 679  *
 680  * Controlling globals:
 681  * $wgDebugLogFile - points to the log file
 682  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 683  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 684  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 685  *
 686  * @param $text String
 687  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 688  */
 689 function wfDebug( $text, $logonly = false ) {
 690         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 691         global $wgDebugLogPrefix, $wgShowDebug;
 692
 693         static $cache = array(); // Cache of unoutputted messages
 694         $text = wfDebugTimer() . $text;
 695
 696         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 697                 return;
 698         }
 699
 700         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 701                 $cache[] = $text;
 702
 703                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 704                         // add the message and any cached messages to the output
 705                         array_map( array( $wgOut, 'debug' ), $cache );
 706                         $cache = array();
 707                 }
 708         }
 709         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 710                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 711                         # Strip unprintables; they can switch terminal modes when binary data
 712                         # gets dumped, which is pretty annoying.
 713                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 714                         $text = $wgDebugLogPrefix . $text;
 715                         wfErrorLog( $text, $wgDebugLogFile );
 716                 }
 717         }
 718 }
 719
 720 /**
 721  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 722  */
 723 function wfIsDebugRawPage() {
 724         static $cache;
 725         if ( $cache !== null ) {
 726                 return $cache;
 727         }
 728         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 729         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 730                 || (
 731                         isset( $_SERVER['SCRIPT_NAME'] )
 732                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 733                 ) )
 734         {
 735                 $cache = true;
 736         } else {
 737                 $cache = false;
 738         }
 739         return $cache;
 740 }
 741
 742 /**
 743  * Get microsecond timestamps for debug logs
 744  *
 745  * @return string
 746  */
 747 function wfDebugTimer() {
 748         global $wgDebugTimestamps;
 749         if ( !$wgDebugTimestamps ) {
 750                 return '';
 751         }
 752         static $start = null;
 753
 754         if ( $start === null ) {
 755                 $start = microtime( true );
 756                 $prefix = "\n$start";
 757         } else {
 758                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 759         }
 760         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / (1024*1024) ) );
 761         return "$prefix $mem  " ;
 762 }
 763
 764 /**
 765  * Send a line giving PHP memory usage.
 766  *
 767  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 768  */
 769 function wfDebugMem( $exact = false ) {
 770         $mem = memory_get_usage();
 771         if( !$exact ) {
 772                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 773         } else {
 774                 $mem .= ' bytes';
 775         }
 776         wfDebug( "Memory usage: $mem\n" );
 777 }
 778
 779 /**
 780  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 781  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 782  *
 783  * @param $logGroup String
 784  * @param $text String
 785  * @param $public Bool: whether to log the event in the public log if no private
 786  *                     log file is specified, (default true)
 787  */
 788 function wfDebugLog( $logGroup, $text, $public = true ) {
 789         global $wgDebugLogGroups, $wgShowHostnames;
 790         $text = trim( $text ) . "\n";
 791         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 792                 $time = wfTimestamp( TS_DB );
 793                 $wiki = wfWikiID();
 794                 if ( $wgShowHostnames ) {
 795                         $host = wfHostname();
 796                 } else {
 797                         $host = '';
 798                 }
 799                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 800                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 801                 }
 802         } elseif ( $public === true ) {
 803                 wfDebug( $text, true );
 804         }
 805 }
 806
 807 /**
 808  * Log for database errors
 809  *
 810  * @param $text String: database error message.
 811  */
 812 function wfLogDBError( $text ) {
 813         global $wgDBerrorLog, $wgDBname;
 814         if ( $wgDBerrorLog ) {
 815                 $host = trim(`hostname`);
 816                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 817                 wfErrorLog( $text, $wgDBerrorLog );
 818         }
 819 }
 820
 821 /**
 822  * Log to a file without getting "file size exceeded" signals.
 823  *
 824  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 825  * send lines to the specified port, prefixed by the specified prefix and a space.
 826  *
 827  * @param $text String
 828  * @param $file String filename
 829  */
 830 function wfErrorLog( $text, $file ) {
 831         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 832                 # Needs the sockets extension
 833                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 834                         // IPv6 bracketed host
 835                         $host = $m[2];
 836                         $port = intval( $m[3] );
 837                         $prefix = isset( $m[4] ) ? $m[4] : false;
 838                         $domain = AF_INET6;
 839                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 840                         $host = $m[2];
 841                         if ( !IP::isIPv4( $host ) ) {
 842                                 $host = gethostbyname( $host );
 843                         }
 844                         $port = intval( $m[3] );
 845                         $prefix = isset( $m[4] ) ? $m[4] : false;
 846                         $domain = AF_INET;
 847                 } else {
 848                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 849                 }
 850
 851                 // Clean it up for the multiplexer
 852                 if ( strval( $prefix ) !== '' ) {
 853                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 854
 855                         // Limit to 64KB
 856                         if ( strlen( $text ) > 65506 ) {
 857                                 $text = substr( $text, 0, 65506 );
 858                         }
 859
 860                         if ( substr( $text, -1 ) != "\n" ) {
 861                                 $text .= "\n";
 862                         }
 863                 } elseif ( strlen( $text ) > 65507 ) {
 864                         $text = substr( $text, 0, 65507 );
 865                 }
 866
 867                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 868                 if ( !$sock ) {
 869                         return;
 870                 }
 871
 872                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 873                 socket_close( $sock );
 874         } else {
 875                 wfSuppressWarnings();
 876                 $exists = file_exists( $file );
 877                 $size = $exists ? filesize( $file ) : false;
 878                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 879                         file_put_contents( $file, $text, FILE_APPEND );
 880                 }
 881                 wfRestoreWarnings();
 882         }
 883 }
 884
 885 /**
 886  * @todo document
 887  */
 888 function wfLogProfilingData() {
 889         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 890         global $wgProfileLimit, $wgUser;
 891
 892         $profiler = Profiler::instance();
 893
 894         # Profiling must actually be enabled...
 895         if ( $profiler->isStub() ) {
 896                 return;
 897         }
 898
 899         // Get total page request time and only show pages that longer than
 900         // $wgProfileLimit time (default is 0)
 901         $now = wfTime();
 902         $elapsed = $now - $wgRequestTime;
 903         if ( $elapsed <= $wgProfileLimit ) {
 904                 return;
 905         }
 906
 907         $profiler->logData();
 908
 909         // Check whether this should be logged in the debug file.
 910         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 911                 return;
 912         }
 913
 914         $forward = '';
 915         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 916                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 917         }
 918         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 919                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 920         }
 921         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 922                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 923         }
 924         if ( $forward ) {
 925                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 926         }
 927         // Don't load $wgUser at this late stage just for statistics purposes
 928         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 929         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 930                 $forward .= ' anon';
 931         }
 932         $log = sprintf( "%s\t%04.3f\t%s\n",
 933                 gmdate( 'YmdHis' ), $elapsed,
 934                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 935
 936         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 937 }
 938
 939 /**
 940  * Check if the wiki read-only lock file is present. This can be used to lock
 941  * off editing functions, but doesn't guarantee that the database will not be
 942  * modified.
 943  *
 944  * @return bool
 945  */
 946 function wfReadOnly() {
 947         global $wgReadOnlyFile, $wgReadOnly;
 948
 949         if ( !is_null( $wgReadOnly ) ) {
 950                 return (bool)$wgReadOnly;
 951         }
 952         if ( $wgReadOnlyFile == '' ) {
 953                 return false;
 954         }
 955         // Set $wgReadOnly for faster access next time
 956         if ( is_file( $wgReadOnlyFile ) ) {
 957                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 958         } else {
 959                 $wgReadOnly = false;
 960         }
 961         return (bool)$wgReadOnly;
 962 }
 963
 964 /**
 965  * @return bool
 966  */
 967 function wfReadOnlyReason() {
 968         global $wgReadOnly;
 969         wfReadOnly();
 970         return $wgReadOnly;
 971 }
 972
 973 /**
 974  * Return a Language object from $langcode
 975  *
 976  * @param $langcode Mixed: either:
 977  *                  - a Language object
 978  *                  - code of the language to get the message for, if it is
 979  *                    a valid code create a language for that language, if
 980  *                    it is a string but not a valid code then make a basic
 981  *                    language object
 982  *                  - a boolean: if it's false then use the global object for
 983  *                    the current user's language (as a fallback for the old parameter
 984  *                    functionality), or if it is true then use global object
 985  *                    for the wiki's content language.
 986  * @return Language object
 987  */
 988 function wfGetLangObj( $langcode = false ) {
 989         # Identify which language to get or create a language object for.
 990         # Using is_object here due to Stub objects.
 991         if( is_object( $langcode ) ) {
 992                 # Great, we already have the object (hopefully)!
 993                 return $langcode;
 994         }
 995
 996         global $wgContLang, $wgLanguageCode;
 997         if( $langcode === true || $langcode === $wgLanguageCode ) {
 998                 # $langcode is the language code of the wikis content language object.
 999                 # or it is a boolean and value is true
1000                 return $wgContLang;
1001         }
1002
1003         global $wgLang;
1004         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1005                 # $langcode is the language code of user language object.
1006                 # or it was a boolean and value is false
1007                 return $wgLang;
1008         }
1009
1010         $validCodes = array_keys( Language::getLanguageNames() );
1011         if( in_array( $langcode, $validCodes ) ) {
1012                 # $langcode corresponds to a valid language.
1013                 return Language::factory( $langcode );
1014         }
1015
1016         # $langcode is a string, but not a valid language code; use content language.
1017         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1018         return $wgContLang;
1019 }
1020
1021 /**
1022  * Old function when $wgBetterDirectionality existed
1023  * Removed in core, kept in extensions for backwards compat.
1024  *
1025  * @deprecated since 1.18
1026  * @return Language
1027  */
1028 function wfUILang() {
1029         global $wgLang;
1030         return $wgLang;
1031 }
1032
1033 /**
1034  * This is the new function for getting translated interface messages.
1035  * See the Message class for documentation how to use them.
1036  * The intention is that this function replaces all old wfMsg* functions.
1037  * @param $key \string Message key.
1038  * Varargs: normal message parameters.
1039  * @return Message
1040  * @since 1.17
1041  */
1042 function wfMessage( $key /*...*/) {
1043         $params = func_get_args();
1044         array_shift( $params );
1045         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1046                 $params = $params[0];
1047         }
1048         return new Message( $key, $params );
1049 }
1050
1051 /**
1052  * This function accepts multiple message keys and returns a message instance
1053  * for the first message which is non-empty. If all messages are empty then an
1054  * instance of the first message key is returned.
1055  * @param varargs: message keys
1056  * @return Message
1057  * @since 1.18
1058  */
1059 function wfMessageFallback( /*...*/ ) {
1060         $args = func_get_args();
1061         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1062 }
1063
1064 /**
1065  * Get a message from anywhere, for the current user language.
1066  *
1067  * Use wfMsgForContent() instead if the message should NOT
1068  * change depending on the user preferences.
1069  *
1070  * @param $key String: lookup key for the message, usually
1071  *    defined in languages/Language.php
1072  *
1073  * Parameters to the message, which can be used to insert variable text into
1074  * it, can be passed to this function in the following formats:
1075  * - One per argument, starting at the second parameter
1076  * - As an array in the second parameter
1077  * These are not shown in the function definition.
1078  *
1079  * @return String
1080  */
1081 function wfMsg( $key ) {
1082         $args = func_get_args();
1083         array_shift( $args );
1084         return wfMsgReal( $key, $args );
1085 }
1086
1087 /**
1088  * Same as above except doesn't transform the message
1089  *
1090  * @param $key String
1091  * @return String
1092  */
1093 function wfMsgNoTrans( $key ) {
1094         $args = func_get_args();
1095         array_shift( $args );
1096         return wfMsgReal( $key, $args, true, false, false );
1097 }
1098
1099 /**
1100  * Get a message from anywhere, for the current global language
1101  * set with $wgLanguageCode.
1102  *
1103  * Use this if the message should NOT change dependent on the
1104  * language set in the user's preferences. This is the case for
1105  * most text written into logs, as well as link targets (such as
1106  * the name of the copyright policy page). Link titles, on the
1107  * other hand, should be shown in the UI language.
1108  *
1109  * Note that MediaWiki allows users to change the user interface
1110  * language in their preferences, but a single installation
1111  * typically only contains content in one language.
1112  *
1113  * Be wary of this distinction: If you use wfMsg() where you should
1114  * use wfMsgForContent(), a user of the software may have to
1115  * customize potentially hundreds of messages in
1116  * order to, e.g., fix a link in every possible language.
1117  *
1118  * @param $key String: lookup key for the message, usually
1119  *     defined in languages/Language.php
1120  * @return String
1121  */
1122 function wfMsgForContent( $key ) {
1123         global $wgForceUIMsgAsContentMsg;
1124         $args = func_get_args();
1125         array_shift( $args );
1126         $forcontent = true;
1127         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1128                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1129         {
1130                 $forcontent = false;
1131         }
1132         return wfMsgReal( $key, $args, true, $forcontent );
1133 }
1134
1135 /**
1136  * Same as above except doesn't transform the message
1137  *
1138  * @param $key String
1139  * @return String
1140  */
1141 function wfMsgForContentNoTrans( $key ) {
1142         global $wgForceUIMsgAsContentMsg;
1143         $args = func_get_args();
1144         array_shift( $args );
1145         $forcontent = true;
1146         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1147                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1148         {
1149                 $forcontent = false;
1150         }
1151         return wfMsgReal( $key, $args, true, $forcontent, false );
1152 }
1153
1154 /**
1155  * Really get a message
1156  *
1157  * @param $key String: key to get.
1158  * @param $args
1159  * @param $useDB Boolean
1160  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1161  * @param $transform Boolean: Whether or not to transform the message.
1162  * @return String: the requested message.
1163  */
1164 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1165         wfProfileIn( __METHOD__ );
1166         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1167         $message = wfMsgReplaceArgs( $message, $args );
1168         wfProfileOut( __METHOD__ );
1169         return $message;
1170 }
1171
1172 /**
1173  * Fetch a message string value, but don't replace any keys yet.
1174  *
1175  * @param $key String
1176  * @param $useDB Bool
1177  * @param $langCode String: Code of the language to get the message for, or
1178  *                  behaves as a content language switch if it is a boolean.
1179  * @param $transform Boolean: whether to parse magic words, etc.
1180  * @return string
1181  */
1182 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1183         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1184
1185         $cache = MessageCache::singleton();
1186         $message = $cache->get( $key, $useDB, $langCode );
1187         if( $message === false ) {
1188                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1189         } elseif ( $transform ) {
1190                 $message = $cache->transform( $message );
1191         }
1192         return $message;
1193 }
1194
1195 /**
1196  * Replace message parameter keys on the given formatted output.
1197  *
1198  * @param $message String
1199  * @param $args Array
1200  * @return string
1201  * @private
1202  */
1203 function wfMsgReplaceArgs( $message, $args ) {
1204         # Fix windows line-endings
1205         # Some messages are split with explode("\n", $msg)
1206         $message = str_replace( "\r", '', $message );
1207
1208         // Replace arguments
1209         if ( count( $args ) ) {
1210                 if ( is_array( $args[0] ) ) {
1211                         $args = array_values( $args[0] );
1212                 }
1213                 $replacementKeys = array();
1214                 foreach( $args as $n => $param ) {
1215                         $replacementKeys['$' . ( $n + 1 )] = $param;
1216                 }
1217                 $message = strtr( $message, $replacementKeys );
1218         }
1219
1220         return $message;
1221 }
1222
1223 /**
1224  * Return an HTML-escaped version of a message.
1225  * Parameter replacements, if any, are done *after* the HTML-escaping,
1226  * so parameters may contain HTML (eg links or form controls). Be sure
1227  * to pre-escape them if you really do want plaintext, or just wrap
1228  * the whole thing in htmlspecialchars().
1229  *
1230  * @param $key String
1231  * @param string ... parameters
1232  * @return string
1233  */
1234 function wfMsgHtml( $key ) {
1235         $args = func_get_args();
1236         array_shift( $args );
1237         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1238 }
1239
1240 /**
1241  * Return an HTML version of message
1242  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1243  * so parameters may contain HTML (eg links or form controls). Be sure
1244  * to pre-escape them if you really do want plaintext, or just wrap
1245  * the whole thing in htmlspecialchars().
1246  *
1247  * @param $key String
1248  * @param string ... parameters
1249  * @return string
1250  */
1251 function wfMsgWikiHtml( $key ) {
1252         $args = func_get_args();
1253         array_shift( $args );
1254         return wfMsgReplaceArgs(
1255                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1256                 /* can't be set to false */ true, /* interface */ true )->getText(),
1257                 $args );
1258 }
1259
1260 /**
1261  * Returns message in the requested format
1262  * @param $key String: key of the message
1263  * @param $options Array: processing rules. Can take the following options:
1264  *   <i>parse</i>: parses wikitext to HTML
1265  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1266  *       p's added by parser or tidy
1267  *   <i>escape</i>: filters message through htmlspecialchars
1268  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1269  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1270  *   <i>parsemag</i>: transform the message using magic phrases
1271  *   <i>content</i>: fetch message for content language instead of interface
1272  * Also can accept a single associative argument, of the form 'language' => 'xx':
1273  *   <i>language</i>: Language object or language code to fetch message for
1274  *       (overriden by <i>content</i>).
1275  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1276  *
1277  * @return String
1278  */
1279 function wfMsgExt( $key, $options ) {
1280         $args = func_get_args();
1281         array_shift( $args );
1282         array_shift( $args );
1283         $options = (array)$options;
1284
1285         foreach( $options as $arrayKey => $option ) {
1286                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1287                         # An unknown index, neither numeric nor "language"
1288                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1289                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1290                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1291                 'replaceafter', 'parsemag', 'content' ) ) ) {
1292                         # A numeric index with unknown value
1293                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1294                 }
1295         }
1296
1297         if( in_array( 'content', $options, true ) ) {
1298                 $forContent = true;
1299                 $langCode = true;
1300                 $langCodeObj = null;
1301         } elseif( array_key_exists( 'language', $options ) ) {
1302                 $forContent = false;
1303                 $langCode = wfGetLangObj( $options['language'] );
1304                 $langCodeObj = $langCode;
1305         } else {
1306                 $forContent = false;
1307                 $langCode = false;
1308                 $langCodeObj = null;
1309         }
1310
1311         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1312
1313         if( !in_array( 'replaceafter', $options, true ) ) {
1314                 $string = wfMsgReplaceArgs( $string, $args );
1315         }
1316
1317         $messageCache = MessageCache::singleton();
1318         if( in_array( 'parse', $options, true ) ) {
1319                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1320         } elseif ( in_array( 'parseinline', $options, true ) ) {
1321                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1322                 $m = array();
1323                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1324                         $string = $m[1];
1325                 }
1326         } elseif ( in_array( 'parsemag', $options, true ) ) {
1327                 $string = $messageCache->transform( $string,
1328                                 !$forContent, $langCodeObj );
1329         }
1330
1331         if ( in_array( 'escape', $options, true ) ) {
1332                 $string = htmlspecialchars ( $string );
1333         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1334                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1335         }
1336
1337         if( in_array( 'replaceafter', $options, true ) ) {
1338                 $string = wfMsgReplaceArgs( $string, $args );
1339         }
1340
1341         return $string;
1342 }
1343
1344 /**
1345  * Since wfMsg() and co suck, they don't return false if the message key they
1346  * looked up didn't exist but a XHTML string, this function checks for the
1347  * nonexistance of messages by checking the MessageCache::get() result directly.
1348  *
1349  * @param $key      String: the message key looked up
1350  * @return Boolean True if the message *doesn't* exist.
1351  */
1352 function wfEmptyMsg( $key ) {
1353         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1354 }
1355
1356 /**
1357  * Throw a debugging exception. This function previously once exited the process,
1358  * but now throws an exception instead, with similar results.
1359  *
1360  * @param $msg String: message shown when dying.
1361  */
1362 function wfDebugDieBacktrace( $msg = '' ) {
1363         throw new MWException( $msg );
1364 }
1365
1366 /**
1367  * Fetch server name for use in error reporting etc.
1368  * Use real server name if available, so we know which machine
1369  * in a server farm generated the current page.
1370  *
1371  * @return string
1372  */
1373 function wfHostname() {
1374         static $host;
1375         if ( is_null( $host ) ) {
1376                 if ( function_exists( 'posix_uname' ) ) {
1377                         // This function not present on Windows
1378                         $uname = posix_uname();
1379                 } else {
1380                         $uname = false;
1381                 }
1382                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1383                         $host = $uname['nodename'];
1384                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1385                         # Windows computer name
1386                         $host = getenv( 'COMPUTERNAME' );
1387                 } else {
1388                         # This may be a virtual server.
1389                         $host = $_SERVER['SERVER_NAME'];
1390                 }
1391         }
1392         return $host;
1393 }
1394
1395 /**
1396  * Returns a HTML comment with the elapsed time since request.
1397  * This method has no side effects.
1398  *
1399  * @return string
1400  */
1401 function wfReportTime() {
1402         global $wgRequestTime, $wgShowHostnames;
1403
1404         $now = wfTime();
1405         $elapsed = $now - $wgRequestTime;
1406
1407         return $wgShowHostnames
1408                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1409                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1410 }
1411
1412 /**
1413  * Safety wrapper for debug_backtrace().
1414  *
1415  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1416  * murky circumstances, which may be triggered in part by stub objects
1417  * or other fancy talkin'.
1418  *
1419  * Will return an empty array if Zend Optimizer is detected or if
1420  * debug_backtrace is disabled, otherwise the output from
1421  * debug_backtrace() (trimmed).
1422  *
1423  * @param $limit int This parameter can be used to limit the number of stack frames returned
1424  *
1425  * @return array of backtrace information
1426  */
1427 function wfDebugBacktrace( $limit = 0 ) {
1428         static $disabled = null;
1429
1430         if( extension_loaded( 'Zend Optimizer' ) ) {
1431                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1432                 return array();
1433         }
1434
1435         if ( is_null( $disabled ) ) {
1436                 $disabled = false;
1437                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1438                 $functions = array_map( 'trim', $functions );
1439                 $functions = array_map( 'strtolower', $functions );
1440                 if ( in_array( 'debug_backtrace', $functions ) ) {
1441                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1442                         $disabled = true;
1443                 }
1444         }
1445         if ( $disabled ) {
1446                 return array();
1447         }
1448
1449         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1450                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1451         } else {
1452                 return array_slice( debug_backtrace(), 1 );
1453         }
1454 }
1455
1456 /**
1457  * Get a debug backtrace as a string
1458  *
1459  * @return string
1460  */
1461 function wfBacktrace() {
1462         global $wgCommandLineMode;
1463
1464         if ( $wgCommandLineMode ) {
1465                 $msg = '';
1466         } else {
1467                 $msg = "<ul>\n";
1468         }
1469         $backtrace = wfDebugBacktrace();
1470         foreach( $backtrace as $call ) {
1471                 if( isset( $call['file'] ) ) {
1472                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1473                         $file = $f[count( $f ) - 1];
1474                 } else {
1475                         $file = '-';
1476                 }
1477                 if( isset( $call['line'] ) ) {
1478                         $line = $call['line'];
1479                 } else {
1480                         $line = '-';
1481                 }
1482                 if ( $wgCommandLineMode ) {
1483                         $msg .= "$file line $line calls ";
1484                 } else {
1485                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1486                 }
1487                 if( !empty( $call['class'] ) ) {
1488                         $msg .= $call['class'] . $call['type'];
1489                 }
1490                 $msg .= $call['function'] . '()';
1491
1492                 if ( $wgCommandLineMode ) {
1493                         $msg .= "\n";
1494                 } else {
1495                         $msg .= "</li>\n";
1496                 }
1497         }
1498         if ( $wgCommandLineMode ) {
1499                 $msg .= "\n";
1500         } else {
1501                 $msg .= "</ul>\n";
1502         }
1503
1504         return $msg;
1505 }
1506
1507 /**
1508  * Get the name of the function which called this function
1509  *
1510  * @param $level Int
1511  * @return Bool|string
1512  */
1513 function wfGetCaller( $level = 2 ) {
1514         $backtrace = wfDebugBacktrace( $level );
1515         if ( isset( $backtrace[$level] ) ) {
1516                 return wfFormatStackFrame( $backtrace[$level] );
1517         } else {
1518                 $caller = 'unknown';
1519         }
1520         return $caller;
1521 }
1522
1523 /**
1524  * Return a string consisting of callers in the stack. Useful sometimes
1525  * for profiling specific points.
1526  *
1527  * @param $limit The maximum depth of the stack frame to return, or false for
1528  *               the entire stack.
1529  * @return String
1530  */
1531 function wfGetAllCallers( $limit = 3 ) {
1532         $trace = array_reverse( wfDebugBacktrace() );
1533         if ( !$limit || $limit > count( $trace ) - 1 ) {
1534                 $limit = count( $trace ) - 1;
1535         }
1536         $trace = array_slice( $trace, -$limit - 1, $limit );
1537         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1538 }
1539
1540 /**
1541  * Return a string representation of frame
1542  *
1543  * @param $frame Array
1544  * @return Bool
1545  */
1546 function wfFormatStackFrame( $frame ) {
1547         return isset( $frame['class'] ) ?
1548                 $frame['class'] . '::' . $frame['function'] :
1549                 $frame['function'];
1550 }
1551
1552
1553 /* Some generic result counters, pulled out of SearchEngine */
1554
1555
1556 /**
1557  * @todo document
1558  *
1559  * @param $offset Int
1560  * @param $limit Int
1561  * @return String
1562  */
1563 function wfShowingResults( $offset, $limit ) {
1564         global $wgLang;
1565         return wfMsgExt(
1566                 'showingresults',
1567                 array( 'parseinline' ),
1568                 $wgLang->formatNum( $limit ),
1569                 $wgLang->formatNum( $offset + 1 )
1570         );
1571 }
1572
1573 /**
1574  * Generate (prev x| next x) (20|50|100...) type links for paging
1575  *
1576  * @param $offset String
1577  * @param $limit Integer
1578  * @param $link String
1579  * @param $query String: optional URL query parameter string
1580  * @param $atend Bool: optional param for specified if this is the last page
1581  * @return String
1582  * @deprecated in 1.19; use Language::viewPrevNext() instead
1583  */
1584 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1585         global $wgLang;
1586
1587         $query = wfCgiToArray( $query );
1588
1589         if( is_object( $link ) ) {
1590                 $title = $link;
1591         } else {
1592                 $title = Title::newFromText( $link );
1593                 if( is_null( $title ) ) {
1594                         return false;
1595                 }
1596         }
1597
1598         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1599 }
1600
1601 /**
1602  * Make a list item, used by various special pages
1603  *
1604  * @param $page String Page link
1605  * @param $details String Text between brackets
1606  * @param $oppositedm Boolean   Add the direction mark opposite to your
1607  *                                                              language, to display text properly
1608  * @return String
1609  * @deprecated since 1.19; use Language::specialList() instead
1610  */
1611 function wfSpecialList( $page, $details, $oppositedm = true ) {
1612         global $wgLang;
1613         return $wgLang->specialList( $page, $details, $oppositedm );
1614 }
1615
1616 /**
1617  * @todo document
1618  * @todo FIXME: We may want to blacklist some broken browsers
1619  *
1620  * @param $force Bool
1621  * @return bool Whereas client accept gzip compression
1622  */
1623 function wfClientAcceptsGzip( $force = false ) {
1624         static $result = null;
1625         if ( $result === null || $force ) {
1626                 $result = false;
1627                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1628                         # @todo FIXME: We may want to blacklist some broken browsers
1629                         $m = array();
1630                         if( preg_match(
1631                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1632                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1633                                 $m )
1634                         )
1635                         {
1636                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1637                                         $result = false;
1638                                         return $result;
1639                                 }
1640                                 wfDebug( " accepts gzip\n" );
1641                                 $result = true;
1642                         }
1643                 }
1644         }
1645         return $result;
1646 }
1647
1648 /**
1649  * Obtain the offset and limit values from the request string;
1650  * used in special pages
1651  *
1652  * @param $deflimit Int default limit if none supplied
1653  * @param $optionname String Name of a user preference to check against
1654  * @return array
1655  *
1656  */
1657 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1658         global $wgRequest;
1659         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1660 }
1661
1662 /**
1663  * Escapes the given text so that it may be output using addWikiText()
1664  * without any linking, formatting, etc. making its way through. This
1665  * is achieved by substituting certain characters with HTML entities.
1666  * As required by the callers, <nowiki> is not used.
1667  *
1668  * @param $text String: text to be escaped
1669  * @return String
1670  */
1671 function wfEscapeWikiText( $text ) {
1672         $text = strtr( "\n$text", array(
1673                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1674                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1675                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1676                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1677                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1678                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1679         ) );
1680         return substr( $text, 1 );
1681 }
1682
1683 /**
1684  * Get the current unix timetstamp with microseconds.  Useful for profiling
1685  * @return Float
1686  */
1687 function wfTime() {
1688         return microtime( true );
1689 }
1690
1691 /**
1692  * Sets dest to source and returns the original value of dest
1693  * If source is NULL, it just returns the value, it doesn't set the variable
1694  * If force is true, it will set the value even if source is NULL
1695  *
1696  * @param $dest Mixed
1697  * @param $source Mixed
1698  * @param $force Bool
1699  * @return Mixed
1700  */
1701 function wfSetVar( &$dest, $source, $force = false ) {
1702         $temp = $dest;
1703         if ( !is_null( $source ) || $force ) {
1704                 $dest = $source;
1705         }
1706         return $temp;
1707 }
1708
1709 /**
1710  * As for wfSetVar except setting a bit
1711  *
1712  * @param $dest Int
1713  * @param $bit Int
1714  * @param $state Bool
1715  */
1716 function wfSetBit( &$dest, $bit, $state = true ) {
1717         $temp = (bool)( $dest & $bit );
1718         if ( !is_null( $state ) ) {
1719                 if ( $state ) {
1720                         $dest |= $bit;
1721                 } else {
1722                         $dest &= ~$bit;
1723                 }
1724         }
1725         return $temp;
1726 }
1727
1728 /**
1729  * A wrapper around the PHP function var_export().
1730  * Either print it or add it to the regular output ($wgOut).
1731  *
1732  * @param $var A PHP variable to dump.
1733  */
1734 function wfVarDump( $var ) {
1735         global $wgOut;
1736         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1737         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1738                 print $s;
1739         } else {
1740                 $wgOut->addHTML( $s );
1741         }
1742 }
1743
1744 /**
1745  * Provide a simple HTTP error.
1746  *
1747  * @param $code Int|String
1748  * @param $label String
1749  * @param $desc String
1750  */
1751 function wfHttpError( $code, $label, $desc ) {
1752         global $wgOut;
1753         $wgOut->disable();
1754         header( "HTTP/1.0 $code $label" );
1755         header( "Status: $code $label" );
1756         $wgOut->sendCacheControl();
1757
1758         header( 'Content-type: text/html; charset=utf-8' );
1759         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1760                 '<html><head><title>' .
1761                 htmlspecialchars( $label ) .
1762                 '</title></head><body><h1>' .
1763                 htmlspecialchars( $label ) .
1764                 '</h1><p>' .
1765                 nl2br( htmlspecialchars( $desc ) ) .
1766                 "</p></body></html>\n";
1767 }
1768
1769 /**
1770  * Clear away any user-level output buffers, discarding contents.
1771  *
1772  * Suitable for 'starting afresh', for instance when streaming
1773  * relatively large amounts of data without buffering, or wanting to
1774  * output image files without ob_gzhandler's compression.
1775  *
1776  * The optional $resetGzipEncoding parameter controls suppression of
1777  * the Content-Encoding header sent by ob_gzhandler; by default it
1778  * is left. See comments for wfClearOutputBuffers() for why it would
1779  * be used.
1780  *
1781  * Note that some PHP configuration options may add output buffer
1782  * layers which cannot be removed; these are left in place.
1783  *
1784  * @param $resetGzipEncoding Bool
1785  */
1786 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1787         if( $resetGzipEncoding ) {
1788                 // Suppress Content-Encoding and Content-Length
1789                 // headers from 1.10+s wfOutputHandler
1790                 global $wgDisableOutputCompression;
1791                 $wgDisableOutputCompression = true;
1792         }
1793         while( $status = ob_get_status() ) {
1794                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1795                         // Probably from zlib.output_compression or other
1796                         // PHP-internal setting which can't be removed.
1797                         //
1798                         // Give up, and hope the result doesn't break
1799                         // output behavior.
1800                         break;
1801                 }
1802                 if( !ob_end_clean() ) {
1803                         // Could not remove output buffer handler; abort now
1804                         // to avoid getting in some kind of infinite loop.
1805                         break;
1806                 }
1807                 if( $resetGzipEncoding ) {
1808                         if( $status['name'] == 'ob_gzhandler' ) {
1809                                 // Reset the 'Content-Encoding' field set by this handler
1810                                 // so we can start fresh.
1811                                 if ( function_exists( 'header_remove' ) ) {
1812                                         // Available since PHP 5.3.0
1813                                         header_remove( 'Content-Encoding' );
1814                                 } else {
1815                                         // We need to provide a valid content-coding. See bug 28069
1816                                         header( 'Content-Encoding: identity' );
1817                                 }
1818                                 break;
1819                         }
1820                 }
1821         }
1822 }
1823
1824 /**
1825  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1826  *
1827  * Clear away output buffers, but keep the Content-Encoding header
1828  * produced by ob_gzhandler, if any.
1829  *
1830  * This should be used for HTTP 304 responses, where you need to
1831  * preserve the Content-Encoding header of the real result, but
1832  * also need to suppress the output of ob_gzhandler to keep to spec
1833  * and avoid breaking Firefox in rare cases where the headers and
1834  * body are broken over two packets.
1835  */
1836 function wfClearOutputBuffers() {
1837         wfResetOutputBuffers( false );
1838 }
1839
1840 /**
1841  * Converts an Accept-* header into an array mapping string values to quality
1842  * factors
1843  *
1844  * @param $accept String
1845  * @param $def String default
1846  * @return Array
1847  */
1848 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1849         # No arg means accept anything (per HTTP spec)
1850         if( !$accept ) {
1851                 return array( $def => 1.0 );
1852         }
1853
1854         $prefs = array();
1855
1856         $parts = explode( ',', $accept );
1857
1858         foreach( $parts as $part ) {
1859                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1860                 $values = explode( ';', trim( $part ) );
1861                 $match = array();
1862                 if ( count( $values ) == 1 ) {
1863                         $prefs[$values[0]] = 1.0;
1864                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1865                         $prefs[$values[0]] = floatval( $match[1] );
1866                 }
1867         }
1868
1869         return $prefs;
1870 }
1871
1872 /**
1873  * Checks if a given MIME type matches any of the keys in the given
1874  * array. Basic wildcards are accepted in the array keys.
1875  *
1876  * Returns the matching MIME type (or wildcard) if a match, otherwise
1877  * NULL if no match.
1878  *
1879  * @param $type String
1880  * @param $avail Array
1881  * @return string
1882  * @private
1883  */
1884 function mimeTypeMatch( $type, $avail ) {
1885         if( array_key_exists( $type, $avail ) ) {
1886                 return $type;
1887         } else {
1888                 $parts = explode( '/', $type );
1889                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1890                         return $parts[0] . '/*';
1891                 } elseif( array_key_exists( '*/*', $avail ) ) {
1892                         return '*/*';
1893                 } else {
1894                         return null;
1895                 }
1896         }
1897 }
1898
1899 /**
1900  * Returns the 'best' match between a client's requested internet media types
1901  * and the server's list of available types. Each list should be an associative
1902  * array of type to preference (preference is a float between 0.0 and 1.0).
1903  * Wildcards in the types are acceptable.
1904  *
1905  * @param $cprefs Array: client's acceptable type list
1906  * @param $sprefs Array: server's offered types
1907  * @return string
1908  *
1909  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1910  * XXX: generalize to negotiate other stuff
1911  */
1912 function wfNegotiateType( $cprefs, $sprefs ) {
1913         $combine = array();
1914
1915         foreach( array_keys( $sprefs ) as $type ) {
1916                 $parts = explode( '/', $type );
1917                 if( $parts[1] != '*' ) {
1918                         $ckey = mimeTypeMatch( $type, $cprefs );
1919                         if( $ckey ) {
1920                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1921                         }
1922                 }
1923         }
1924
1925         foreach( array_keys( $cprefs ) as $type ) {
1926                 $parts = explode( '/', $type );
1927                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1928                         $skey = mimeTypeMatch( $type, $sprefs );
1929                         if( $skey ) {
1930                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1931                         }
1932                 }
1933         }
1934
1935         $bestq = 0;
1936         $besttype = null;
1937
1938         foreach( array_keys( $combine ) as $type ) {
1939                 if( $combine[$type] > $bestq ) {
1940                         $besttype = $type;
1941                         $bestq = $combine[$type];
1942                 }
1943         }
1944
1945         return $besttype;
1946 }
1947
1948 /**
1949  * Reference-counted warning suppression
1950  *
1951  * @param $end Bool
1952  */
1953 function wfSuppressWarnings( $end = false ) {
1954         static $suppressCount = 0;
1955         static $originalLevel = false;
1956
1957         if ( $end ) {
1958                 if ( $suppressCount ) {
1959                         --$suppressCount;
1960                         if ( !$suppressCount ) {
1961                                 error_reporting( $originalLevel );
1962                         }
1963                 }
1964         } else {
1965                 if ( !$suppressCount ) {
1966                         // E_DEPRECATED is undefined in PHP 5.2
1967                         if( !defined( 'E_DEPRECATED' ) ) {
1968                                 define( 'E_DEPRECATED', 8192 );
1969                         }
1970                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
1971                 }
1972                 ++$suppressCount;
1973         }
1974 }
1975
1976 /**
1977  * Restore error level to previous value
1978  */
1979 function wfRestoreWarnings() {
1980         wfSuppressWarnings( true );
1981 }
1982
1983 # Autodetect, convert and provide timestamps of various types
1984
1985 /**
1986  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1987  */
1988 define( 'TS_UNIX', 0 );
1989
1990 /**
1991  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1992  */
1993 define( 'TS_MW', 1 );
1994
1995 /**
1996  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1997  */
1998 define( 'TS_DB', 2 );
1999
2000 /**
2001  * RFC 2822 format, for E-mail and HTTP headers
2002  */
2003 define( 'TS_RFC2822', 3 );
2004
2005 /**
2006  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2007  *
2008  * This is used by Special:Export
2009  */
2010 define( 'TS_ISO_8601', 4 );
2011
2012 /**
2013  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2014  *
2015  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2016  *       DateTime tag and page 36 for the DateTimeOriginal and
2017  *       DateTimeDigitized tags.
2018  */
2019 define( 'TS_EXIF', 5 );
2020
2021 /**
2022  * Oracle format time.
2023  */
2024 define( 'TS_ORACLE', 6 );
2025
2026 /**
2027  * Postgres format time.
2028  */
2029 define( 'TS_POSTGRES', 7 );
2030
2031 /**
2032  * DB2 format time
2033  */
2034 define( 'TS_DB2', 8 );
2035
2036 /**
2037  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2038  */
2039 define( 'TS_ISO_8601_BASIC', 9 );
2040
2041 /**
2042  * Get a timestamp string in one of various formats
2043  *
2044  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2045  *                    function will autodetect which format is supplied and act
2046  *                    accordingly.
2047  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2048  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2049  */
2050 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2051         $uts = 0;
2052         $da = array();
2053         $strtime = '';
2054
2055         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2056                 $uts = time();
2057                 $strtime = "@$uts";
2058         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2059                 # TS_DB
2060         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2061                 # TS_EXIF
2062         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2063                 # TS_MW
2064         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2065                 # TS_UNIX
2066                 $uts = $ts;
2067                 $strtime = "@$ts"; // Undocumented?
2068         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2069                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2070                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2071                                 str_replace( '+00:00', 'UTC', $ts ) );
2072         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2073                 # TS_ISO_8601
2074         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2075                 #TS_ISO_8601_BASIC
2076         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2077                 # TS_POSTGRES
2078         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2079                 # TS_POSTGRES
2080         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2081                 # TS_DB2
2082         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2083                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2084                                                         '[ \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
2085                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2086                 # The regex is a superset of rfc2822 for readability
2087                 $strtime = strtok( $ts, ';' );
2088         } 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 ) ) {
2089                 # TS_RFC850
2090                 $strtime = $ts;
2091         } 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 ) ) {
2092                 # asctime
2093                 $strtime = $ts;
2094         } else {
2095                 # Bogus value...
2096                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2097
2098                 return false;
2099         }
2100
2101         static $formats = array(
2102                 TS_UNIX => 'U',
2103                 TS_MW => 'YmdHis',
2104                 TS_DB => 'Y-m-d H:i:s',
2105                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2106                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2107                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2108                 TS_RFC2822 => 'D, d M Y H:i:s',
2109                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2110                 TS_POSTGRES => 'Y-m-d H:i:s',
2111                 TS_DB2 => 'Y-m-d H:i:s',
2112         );
2113
2114         if ( !isset( $formats[$outputtype] ) ) {
2115                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2116         }
2117
2118         if ( function_exists( "date_create" ) ) {
2119                 if ( count( $da ) ) {
2120                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2121                                 (int)$da[1], (int)$da[2], (int)$da[3],
2122                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2123
2124                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2125                 } elseif ( $strtime ) {
2126                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2127                 } else {
2128                         return false;
2129                 }
2130
2131                 if ( !$d ) {
2132                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2133                         return false;
2134                 }
2135
2136                 $output = $d->format( $formats[$outputtype] );
2137         } else {
2138                 if ( count( $da ) ) {
2139                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2140                         // We may want to handle that explicitly at some point
2141                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2142                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2143                 } elseif ( $strtime ) {
2144                         $uts = strtotime( $strtime );
2145                 }
2146
2147                 if ( $uts === false ) {
2148                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2149                         return false;
2150                 }
2151
2152                 if ( TS_UNIX == $outputtype ) {
2153                         return $uts;
2154                 }
2155                 $output = gmdate( $formats[$outputtype], $uts );
2156         }
2157
2158         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2159                 $output .= ' GMT';
2160         }
2161
2162         return $output;
2163 }
2164
2165 /**
2166  * Return a formatted timestamp, or null if input is null.
2167  * For dealing with nullable timestamp columns in the database.
2168  *
2169  * @param $outputtype Integer
2170  * @param $ts String
2171  * @return String
2172  */
2173 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2174         if( is_null( $ts ) ) {
2175                 return null;
2176         } else {
2177                 return wfTimestamp( $outputtype, $ts );
2178         }
2179 }
2180
2181 /**
2182  * Convenience function; returns MediaWiki timestamp for the present time.
2183  *
2184  * @return string
2185  */
2186 function wfTimestampNow() {
2187         # return NOW
2188         return wfTimestamp( TS_MW, time() );
2189 }
2190
2191 /**
2192  * Check if the operating system is Windows
2193  *
2194  * @return Bool: true if it's Windows, False otherwise.
2195  */
2196 function wfIsWindows() {
2197         static $isWindows = null;
2198         if ( $isWindows === null ) {
2199                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2200         }
2201         return $isWindows;
2202 }
2203
2204 /**
2205  * Check if we are running under HipHop
2206  *
2207  * @return Bool
2208  */
2209 function wfIsHipHop() {
2210         return function_exists( 'hphp_thread_set_warmup_enabled' );
2211 }
2212
2213 /**
2214  * Swap two variables
2215  *
2216  * @param $x Mixed
2217  * @param $y Mixed
2218  */
2219 function swap( &$x, &$y ) {
2220         $z = $x;
2221         $x = $y;
2222         $y = $z;
2223 }
2224
2225 /**
2226  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2227  * TEMP environment variables are then checked in sequence, and if none are set
2228  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2229  * or C:\Windows\Temp for Windows and hope for the best.
2230  * It is common to call it with tempnam().
2231  *
2232  * NOTE: When possible, use instead the tmpfile() function to create
2233  * temporary files to avoid race conditions on file creation, etc.
2234  *
2235  * @return String
2236  */
2237 function wfTempDir() {
2238         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2239                 $tmp = getenv( $var );
2240                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2241                         return $tmp;
2242                 }
2243         }
2244         if( function_exists( 'sys_get_temp_dir' ) ) {
2245                 return sys_get_temp_dir();
2246         }
2247         # Usual defaults
2248         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2249 }
2250
2251 /**
2252  * Make directory, and make all parent directories if they don't exist
2253  *
2254  * @param $dir String: full path to directory to create
2255  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2256  * @param $caller String: optional caller param for debugging.
2257  * @return bool
2258  */
2259 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2260         global $wgDirectoryMode;
2261
2262         if ( !is_null( $caller ) ) {
2263                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2264         }
2265
2266         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2267                 return true;
2268         }
2269
2270         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2271
2272         if ( is_null( $mode ) ) {
2273                 $mode = $wgDirectoryMode;
2274         }
2275
2276         // Turn off the normal warning, we're doing our own below
2277         wfSuppressWarnings();
2278         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2279         wfRestoreWarnings();
2280
2281         if( !$ok ) {
2282                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2283                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2284         }
2285         return $ok;
2286 }
2287
2288 /**
2289  * Increment a statistics counter
2290  *
2291  * @param $key String
2292  * @param $count Int
2293  */
2294 function wfIncrStats( $key, $count = 1 ) {
2295         global $wgStatsMethod;
2296
2297         $count = intval( $count );
2298
2299         if( $wgStatsMethod == 'udp' ) {
2300                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2301                 static $socket;
2302
2303                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2304
2305                 if ( !$socket ) {
2306                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2307                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2308                         socket_sendto(
2309                                 $socket,
2310                                 $statline,
2311                                 strlen( $statline ),
2312                                 0,
2313                                 $wgUDPProfilerHost,
2314                                 $wgUDPProfilerPort
2315                         );
2316                 }
2317                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2318                 wfSuppressWarnings();
2319                 socket_sendto(
2320                         $socket,
2321                         $statline,
2322                         strlen( $statline ),
2323                         0,
2324                         $wgUDPProfilerHost,
2325                         $wgUDPProfilerPort
2326                 );
2327                 wfRestoreWarnings();
2328         } elseif( $wgStatsMethod == 'cache' ) {
2329                 global $wgMemc;
2330                 $key = wfMemcKey( 'stats', $key );
2331                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2332                         $wgMemc->add( $key, $count );
2333                 }
2334         } else {
2335                 // Disabled
2336         }
2337 }
2338
2339 /**
2340  * @param $nr Mixed: the number to format
2341  * @param $acc Integer: the number of digits after the decimal point, default 2
2342  * @param $round Boolean: whether or not to round the value, default true
2343  * @return float
2344  */
2345 function wfPercent( $nr, $acc = 2, $round = true ) {
2346         $ret = sprintf( "%.${acc}f", $nr );
2347         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2348 }
2349
2350 /**
2351  * Find out whether or not a mixed variable exists in a string
2352  *
2353  * @param $needle String
2354  * @param $str String
2355  * @param $insensitive Boolean
2356  * @return Boolean
2357  */
2358 function in_string( $needle, $str, $insensitive = false ) {
2359         $func = 'strpos';
2360         if( $insensitive ) $func = 'stripos';
2361
2362         return $func( $str, $needle ) !== false;
2363 }
2364
2365 /**
2366  * Safety wrapper around ini_get() for boolean settings.
2367  * The values returned from ini_get() are pre-normalized for settings
2368  * set via php.ini or php_flag/php_admin_flag... but *not*
2369  * for those set via php_value/php_admin_value.
2370  *
2371  * It's fairly common for people to use php_value instead of php_flag,
2372  * which can leave you with an 'off' setting giving a false positive
2373  * for code that just takes the ini_get() return value as a boolean.
2374  *
2375  * To make things extra interesting, setting via php_value accepts
2376  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2377  * Unrecognized values go false... again opposite PHP's own coercion
2378  * from string to bool.
2379  *
2380  * Luckily, 'properly' set settings will always come back as '0' or '1',
2381  * so we only have to worry about them and the 'improper' settings.
2382  *
2383  * I frickin' hate PHP... :P
2384  *
2385  * @param $setting String
2386  * @return Bool
2387  */
2388 function wfIniGetBool( $setting ) {
2389         $val = ini_get( $setting );
2390         // 'on' and 'true' can't have whitespace around them, but '1' can.
2391         return strtolower( $val ) == 'on'
2392                 || strtolower( $val ) == 'true'
2393                 || strtolower( $val ) == 'yes'
2394                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2395 }
2396
2397 /**
2398  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2399  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2400  *
2401  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2402  *                          should be omitted
2403  * @param $fileName String Name of the library, if not $extension.suffix
2404  * @return Bool - Whether or not the extension is loaded
2405  */
2406 function wfDl( $extension, $fileName = null ) {
2407         if( extension_loaded( $extension ) ) {
2408                 return true;
2409         }
2410
2411         $canDl = false;
2412         $sapi = php_sapi_name();
2413         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2414                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2415         {
2416                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2417                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2418         }
2419
2420         if( $canDl ) {
2421                 $fileName = $fileName ? $fileName : $extension;
2422                 if( wfIsWindows() ) {
2423                         $fileName = 'php_' . $fileName;
2424                 }
2425                 wfSuppressWarnings();
2426                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2427                 wfRestoreWarnings();
2428         }
2429         return extension_loaded( $extension );
2430 }
2431
2432 /**
2433  * Windows-compatible version of escapeshellarg()
2434  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2435  * function puts single quotes in regardless of OS.
2436  *
2437  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2438  * earlier distro releases of PHP)
2439  *
2440  * @param varargs
2441  * @return String
2442  */
2443 function wfEscapeShellArg( ) {
2444         wfInitShellLocale();
2445
2446         $args = func_get_args();
2447         $first = true;
2448         $retVal = '';
2449         foreach ( $args as $arg ) {
2450                 if ( !$first ) {
2451                         $retVal .= ' ';
2452                 } else {
2453                         $first = false;
2454                 }
2455
2456                 if ( wfIsWindows() ) {
2457                         // Escaping for an MSVC-style command line parser and CMD.EXE
2458                         // Refs:
2459                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2460                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2461                         //  * Bug #13518
2462                         //  * CR r63214
2463                         // Double the backslashes before any double quotes. Escape the double quotes.
2464                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2465                         $arg = '';
2466                         $iteration = 0;
2467                         foreach ( $tokens as $token ) {
2468                                 if ( $iteration % 2 == 1 ) {
2469                                         // Delimiter, a double quote preceded by zero or more slashes
2470                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2471                                 } elseif ( $iteration % 4 == 2 ) {
2472                                         // ^ in $token will be outside quotes, need to be escaped
2473                                         $arg .= str_replace( '^', '^^', $token );
2474                                 } else { // $iteration % 4 == 0
2475                                         // ^ in $token will appear inside double quotes, so leave as is
2476                                         $arg .= $token;
2477                                 }
2478                                 $iteration++;
2479                         }
2480                         // Double the backslashes before the end of the string, because
2481                         // we will soon add a quote
2482                         $m = array();
2483                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2484                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2485                         }
2486
2487                         // Add surrounding quotes
2488                         $retVal .= '"' . $arg . '"';
2489                 } else {
2490                         $retVal .= escapeshellarg( $arg );
2491                 }
2492         }
2493         return $retVal;
2494 }
2495
2496 /**
2497  * Execute a shell command, with time and memory limits mirrored from the PHP
2498  * configuration if supported.
2499  * @param $cmd String Command line, properly escaped for shell.
2500  * @param &$retval optional, will receive the program's exit code.
2501  *                 (non-zero is usually failure)
2502  * @param $environ Array optional environment variables which should be
2503  *                 added to the executed command environment.
2504  * @return collected stdout as a string (trailing newlines stripped)
2505  */
2506 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2507         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2508
2509         static $disabled;
2510         if ( is_null( $disabled ) ) {
2511                 $disabled = false;
2512                 if( wfIniGetBool( 'safe_mode' ) ) {
2513                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2514                         $disabled = 'safemode';
2515                 } else {
2516                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2517                         $functions = array_map( 'trim', $functions );
2518                         $functions = array_map( 'strtolower', $functions );
2519                         if ( in_array( 'passthru', $functions ) ) {
2520                                 wfDebug( "passthru is in disabled_functions\n" );
2521                                 $disabled = 'passthru';
2522                         }
2523                 }
2524         }
2525         if ( $disabled ) {
2526                 $retval = 1;
2527                 return $disabled == 'safemode' ?
2528                         'Unable to run external programs in safe mode.' :
2529                         'Unable to run external programs, passthru() is disabled.';
2530         }
2531
2532         wfInitShellLocale();
2533
2534         $envcmd = '';
2535         foreach( $environ as $k => $v ) {
2536                 if ( wfIsWindows() ) {
2537                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2538                          * appear in the environment variable, so we must use carat escaping as documented in
2539                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2540                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2541                          * are listed there but doesn't appear to need it.
2542                          */
2543                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2544                 } else {
2545                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2546                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2547                          */
2548                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2549                 }
2550         }
2551         $cmd = $envcmd . $cmd;
2552
2553         if ( wfIsWindows() ) {
2554                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2555                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2556                 {
2557                         # Hack to work around PHP's flawed invocation of cmd.exe
2558                         # http://news.php.net/php.internals/21796
2559                         # Windows 9x doesn't accept any kind of quotes
2560                         $cmd = '"' . $cmd . '"';
2561                 }
2562         } elseif ( php_uname( 's' ) == 'Linux' ) {
2563                 $time = intval( $wgMaxShellTime );
2564                 $mem = intval( $wgMaxShellMemory );
2565                 $filesize = intval( $wgMaxShellFileSize );
2566
2567                 if ( $time > 0 && $mem > 0 ) {
2568                         $script = "$IP/bin/ulimit4.sh";
2569                         if ( is_executable( $script ) ) {
2570                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2571                         }
2572                 }
2573         }
2574         wfDebug( "wfShellExec: $cmd\n" );
2575
2576         $retval = 1; // error by default?
2577         ob_start();
2578         passthru( $cmd, $retval );
2579         $output = ob_get_contents();
2580         ob_end_clean();
2581
2582         if ( $retval == 127 ) {
2583                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2584         }
2585         return $output;
2586 }
2587
2588 /**
2589  * Workaround for http://bugs.php.net/bug.php?id=45132
2590  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2591  */
2592 function wfInitShellLocale() {
2593         static $done = false;
2594         if ( $done ) {
2595                 return;
2596         }
2597         $done = true;
2598         global $wgShellLocale;
2599         if ( !wfIniGetBool( 'safe_mode' ) ) {
2600                 putenv( "LC_CTYPE=$wgShellLocale" );
2601                 setlocale( LC_CTYPE, $wgShellLocale );
2602         }
2603 }
2604
2605 /**
2606  * Generate a shell-escaped command line string to run a maintenance script.
2607  * Note that $parameters should be a flat array and an option with an argument
2608  * should consist of two consecutive items in the array (do not use "--option value").
2609  * @param $script string MediaWiki maintenance script path
2610  * @param $parameters Array Arguments and options to the script
2611  * @param $options Array Associative array of options:
2612  *              'php': The path to the php executable
2613  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2614  * @return Array
2615  */
2616 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2617         global $wgPhpCli;
2618         // Give site config file a chance to run the script in a wrapper.
2619         // The caller may likely want to call wfBasename() on $script.
2620         wfRunHooks( 'wfShellMaintenanceCmd', array( &$script, &$parameters, &$options ) );
2621         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2622         if ( isset( $options['wrapper'] ) ) {
2623                 $cmd[] = $options['wrapper'];
2624         }
2625         $cmd[] = $script;
2626         // Escape each parameter for shell
2627         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2628 }
2629
2630 /**
2631  * wfMerge attempts to merge differences between three texts.
2632  * Returns true for a clean merge and false for failure or a conflict.
2633  *
2634  * @param $old String
2635  * @param $mine String
2636  * @param $yours String
2637  * @param $result String
2638  * @return Bool
2639  */
2640 function wfMerge( $old, $mine, $yours, &$result ) {
2641         global $wgDiff3;
2642
2643         # This check may also protect against code injection in
2644         # case of broken installations.
2645         wfSuppressWarnings();
2646         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2647         wfRestoreWarnings();
2648
2649         if( !$haveDiff3 ) {
2650                 wfDebug( "diff3 not found\n" );
2651                 return false;
2652         }
2653
2654         # Make temporary files
2655         $td = wfTempDir();
2656         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2657         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2658         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2659
2660         fwrite( $oldtextFile, $old );
2661         fclose( $oldtextFile );
2662         fwrite( $mytextFile, $mine );
2663         fclose( $mytextFile );
2664         fwrite( $yourtextFile, $yours );
2665         fclose( $yourtextFile );
2666
2667         # Check for a conflict
2668         $cmd = $wgDiff3 . ' -a --overlap-only ' .
2669                 wfEscapeShellArg( $mytextName ) . ' ' .
2670                 wfEscapeShellArg( $oldtextName ) . ' ' .
2671                 wfEscapeShellArg( $yourtextName );
2672         $handle = popen( $cmd, 'r' );
2673
2674         if( fgets( $handle, 1024 ) ) {
2675                 $conflict = true;
2676         } else {
2677                 $conflict = false;
2678         }
2679         pclose( $handle );
2680
2681         # Merge differences
2682         $cmd = $wgDiff3 . ' -a -e --merge ' .
2683                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2684         $handle = popen( $cmd, 'r' );
2685         $result = '';
2686         do {
2687                 $data = fread( $handle, 8192 );
2688                 if ( strlen( $data ) == 0 ) {
2689                         break;
2690                 }
2691                 $result .= $data;
2692         } while ( true );
2693         pclose( $handle );
2694         unlink( $mytextName );
2695         unlink( $oldtextName );
2696         unlink( $yourtextName );
2697
2698         if ( $result === '' && $old !== '' && !$conflict ) {
2699                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2700                 $conflict = true;
2701         }
2702         return !$conflict;
2703 }
2704
2705 /**
2706  * Returns unified plain-text diff of two texts.
2707  * Useful for machine processing of diffs.
2708  *
2709  * @param $before String: the text before the changes.
2710  * @param $after String: the text after the changes.
2711  * @param $params String: command-line options for the diff command.
2712  * @return String: unified diff of $before and $after
2713  */
2714 function wfDiff( $before, $after, $params = '-u' ) {
2715         if ( $before == $after ) {
2716                 return '';
2717         }
2718
2719         global $wgDiff;
2720         wfSuppressWarnings();
2721         $haveDiff = $wgDiff && file_exists( $wgDiff );
2722         wfRestoreWarnings();
2723
2724         # This check may also protect against code injection in
2725         # case of broken installations.
2726         if( !$haveDiff ) {
2727                 wfDebug( "diff executable not found\n" );
2728                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2729                 $format = new UnifiedDiffFormatter();
2730                 return $format->format( $diffs );
2731         }
2732
2733         # Make temporary files
2734         $td = wfTempDir();
2735         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2736         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2737
2738         fwrite( $oldtextFile, $before );
2739         fclose( $oldtextFile );
2740         fwrite( $newtextFile, $after );
2741         fclose( $newtextFile );
2742
2743         // Get the diff of the two files
2744         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
2745
2746         $h = popen( $cmd, 'r' );
2747
2748         $diff = '';
2749
2750         do {
2751                 $data = fread( $h, 8192 );
2752                 if ( strlen( $data ) == 0 ) {
2753                         break;
2754                 }
2755                 $diff .= $data;
2756         } while ( true );
2757
2758         // Clean up
2759         pclose( $h );
2760         unlink( $oldtextName );
2761         unlink( $newtextName );
2762
2763         // Kill the --- and +++ lines. They're not useful.
2764         $diff_lines = explode( "\n", $diff );
2765         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
2766                 unset( $diff_lines[0] );
2767         }
2768         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
2769                 unset( $diff_lines[1] );
2770         }
2771
2772         $diff = implode( "\n", $diff_lines );
2773
2774         return $diff;
2775 }
2776
2777 /**
2778  * This function works like "use VERSION" in Perl, the program will die with a
2779  * backtrace if the current version of PHP is less than the version provided
2780  *
2781  * This is useful for extensions which due to their nature are not kept in sync
2782  * with releases, and might depend on other versions of PHP than the main code
2783  *
2784  * Note: PHP might die due to parsing errors in some cases before it ever
2785  *       manages to call this function, such is life
2786  *
2787  * @see perldoc -f use
2788  *
2789  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2790  *                 a float
2791  */
2792 function wfUsePHP( $req_ver ) {
2793         $php_ver = PHP_VERSION;
2794
2795         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2796                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2797         }
2798 }
2799
2800 /**
2801  * This function works like "use VERSION" in Perl except it checks the version
2802  * of MediaWiki, the program will die with a backtrace if the current version
2803  * of MediaWiki is less than the version provided.
2804  *
2805  * This is useful for extensions which due to their nature are not kept in sync
2806  * with releases
2807  *
2808  * @see perldoc -f use
2809  *
2810  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2811  *                 a float
2812  */
2813 function wfUseMW( $req_ver ) {
2814         global $wgVersion;
2815
2816         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2817                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2818         }
2819 }
2820
2821 /**
2822  * Return the final portion of a pathname.
2823  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2824  * http://bugs.php.net/bug.php?id=33898
2825  *
2826  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2827  * We'll consider it so always, as we don't want \s in our Unix paths either.
2828  *
2829  * @param $path String
2830  * @param $suffix String: to remove if present
2831  * @return String
2832  */
2833 function wfBaseName( $path, $suffix = '' ) {
2834         $encSuffix = ( $suffix == '' )
2835                 ? ''
2836                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2837         $matches = array();
2838         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2839                 return $matches[1];
2840         } else {
2841                 return '';
2842         }
2843 }
2844
2845 /**
2846  * Generate a relative path name to the given file.
2847  * May explode on non-matching case-insensitive paths,
2848  * funky symlinks, etc.
2849  *
2850  * @param $path String: absolute destination path including target filename
2851  * @param $from String: Absolute source path, directory only
2852  * @return String
2853  */
2854 function wfRelativePath( $path, $from ) {
2855         // Normalize mixed input on Windows...
2856         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2857         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2858
2859         // Trim trailing slashes -- fix for drive root
2860         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2861         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2862
2863         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2864         $against = explode( DIRECTORY_SEPARATOR, $from );
2865
2866         if( $pieces[0] !== $against[0] ) {
2867                 // Non-matching Windows drive letters?
2868                 // Return a full path.
2869                 return $path;
2870         }
2871
2872         // Trim off common prefix
2873         while( count( $pieces ) && count( $against )
2874                 && $pieces[0] == $against[0] ) {
2875                 array_shift( $pieces );
2876                 array_shift( $against );
2877         }
2878
2879         // relative dots to bump us to the parent
2880         while( count( $against ) ) {
2881                 array_unshift( $pieces, '..' );
2882                 array_shift( $against );
2883         }
2884
2885         array_push( $pieces, wfBaseName( $path ) );
2886
2887         return implode( DIRECTORY_SEPARATOR, $pieces );
2888 }
2889
2890 /**
2891  * Do any deferred updates and clear the list
2892  *
2893  * @deprecated since 1.19
2894  * @see DeferredUpdates::doUpdate()
2895  * @param $commit string
2896  */
2897 function wfDoUpdates( $commit = '' ) {
2898         DeferredUpdates::doUpdates( $commit );
2899 }
2900
2901 /**
2902  * Convert an arbitrarily-long digit string from one numeric base
2903  * to another, optionally zero-padding to a minimum column width.
2904  *
2905  * Supports base 2 through 36; digit values 10-36 are represented
2906  * as lowercase letters a-z. Input is case-insensitive.
2907  *
2908  * @param $input String: of digits
2909  * @param $sourceBase Integer: 2-36
2910  * @param $destBase Integer: 2-36
2911  * @param $pad Integer: 1 or greater
2912  * @param $lowercase Boolean
2913  * @return String or false on invalid input
2914  */
2915 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2916         $input = strval( $input );
2917         if( $sourceBase < 2 ||
2918                 $sourceBase > 36 ||
2919                 $destBase < 2 ||
2920                 $destBase > 36 ||
2921                 $pad < 1 ||
2922                 $sourceBase != intval( $sourceBase ) ||
2923                 $destBase != intval( $destBase ) ||
2924                 $pad != intval( $pad ) ||
2925                 !is_string( $input ) ||
2926                 $input == '' ) {
2927                 return false;
2928         }
2929         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2930         $inDigits = array();
2931         $outChars = '';
2932
2933         // Decode and validate input string
2934         $input = strtolower( $input );
2935         for( $i = 0; $i < strlen( $input ); $i++ ) {
2936                 $n = strpos( $digitChars, $input[$i] );
2937                 if( $n === false || $n > $sourceBase ) {
2938                         return false;
2939                 }
2940                 $inDigits[] = $n;
2941         }
2942
2943         // Iterate over the input, modulo-ing out an output digit
2944         // at a time until input is gone.
2945         while( count( $inDigits ) ) {
2946                 $work = 0;
2947                 $workDigits = array();
2948
2949                 // Long division...
2950                 foreach( $inDigits as $digit ) {
2951                         $work *= $sourceBase;
2952                         $work += $digit;
2953
2954                         if( $work < $destBase ) {
2955                                 // Gonna need to pull another digit.
2956                                 if( count( $workDigits ) ) {
2957                                         // Avoid zero-padding; this lets us find
2958                                         // the end of the input very easily when
2959                                         // length drops to zero.
2960                                         $workDigits[] = 0;
2961                                 }
2962                         } else {
2963                                 // Finally! Actual division!
2964                                 $workDigits[] = intval( $work / $destBase );
2965
2966                                 // Isn't it annoying that most programming languages
2967                                 // don't have a single divide-and-remainder operator,
2968                                 // even though the CPU implements it that way?
2969                                 $work = $work % $destBase;
2970                         }
2971                 }
2972
2973                 // All that division leaves us with a remainder,
2974                 // which is conveniently our next output digit.
2975                 $outChars .= $digitChars[$work];
2976
2977                 // And we continue!
2978                 $inDigits = $workDigits;
2979         }
2980
2981         while( strlen( $outChars ) < $pad ) {
2982                 $outChars .= '0';
2983         }
2984
2985         return strrev( $outChars );
2986 }
2987
2988 /**
2989  * Create an object with a given name and an array of construct parameters
2990  *
2991  * @param $name String
2992  * @param $p Array: parameters
2993  * @return object
2994  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
2995  */
2996 function wfCreateObject( $name, $p ) {
2997         wfDeprecated( __FUNCTION__ );
2998         return MWFunction::newObj( $name, $p );
2999 }
3000
3001 /**
3002  * @return bool
3003  */
3004 function wfHttpOnlySafe() {
3005         global $wgHttpOnlyBlacklist;
3006
3007         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3008                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3009                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3010                                 return false;
3011                         }
3012                 }
3013         }
3014
3015         return true;
3016 }
3017
3018 /**
3019  * Initialise php session
3020  *
3021  * @param $sessionId Bool
3022  */
3023 function wfSetupSession( $sessionId = false ) {
3024         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3025                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3026         if( $wgSessionsInMemcached ) {
3027                 if ( !defined( 'MW_COMPILED' ) ) {
3028                         global $IP;
3029                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3030                 }
3031                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3032                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3033
3034                 // It's necessary to register a shutdown function to call session_write_close(),
3035                 // because by the time the request shutdown function for the session module is
3036                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3037                 // this way are called before object destruction.
3038                 register_shutdown_function( 'memsess_write_close' );
3039         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3040                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3041                 # hasn't already been set to the desired value (that causes errors)
3042                 ini_set( 'session.save_handler', $wgSessionHandler );
3043         }
3044         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3045         wfDebugLog( 'cookie',
3046                 'session_set_cookie_params: "' . implode( '", "',
3047                         array(
3048                                 0,
3049                                 $wgCookiePath,
3050                                 $wgCookieDomain,
3051                                 $wgCookieSecure,
3052                                 $httpOnlySafe ) ) . '"' );
3053         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3054         session_cache_limiter( 'private, must-revalidate' );
3055         if ( $sessionId ) {
3056                 session_id( $sessionId );
3057         }
3058         wfSuppressWarnings();
3059         session_start();
3060         wfRestoreWarnings();
3061 }
3062
3063 /**
3064  * Get an object from the precompiled serialized directory
3065  *
3066  * @param $name String
3067  * @return Mixed: the variable on success, false on failure
3068  */
3069 function wfGetPrecompiledData( $name ) {
3070         global $IP;
3071
3072         $file = "$IP/serialized/$name";
3073         if ( file_exists( $file ) ) {
3074                 $blob = file_get_contents( $file );
3075                 if ( $blob ) {
3076                         return unserialize( $blob );
3077                 }
3078         }
3079         return false;
3080 }
3081
3082 /**
3083  * Get a cache key
3084  *
3085  * @param varargs
3086  * @return String
3087  */
3088 function wfMemcKey( /*... */ ) {
3089         $args = func_get_args();
3090         $key = wfWikiID() . ':' . implode( ':', $args );
3091         $key = str_replace( ' ', '_', $key );
3092         return $key;
3093 }
3094
3095 /**
3096  * Get a cache key for a foreign DB
3097  *
3098  * @param $db String
3099  * @param $prefix String
3100  * @param varargs String
3101  * @return String
3102  */
3103 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3104         $args = array_slice( func_get_args(), 2 );
3105         if ( $prefix ) {
3106                 $key = "$db-$prefix:" . implode( ':', $args );
3107         } else {
3108                 $key = $db . ':' . implode( ':', $args );
3109         }
3110         return $key;
3111 }
3112
3113 /**
3114  * Get an ASCII string identifying this wiki
3115  * This is used as a prefix in memcached keys
3116  *
3117  * @return String
3118  */
3119 function wfWikiID() {
3120         global $wgDBprefix, $wgDBname, $wgWikiID;
3121         if ( $wgWikiID !== false ) {
3122                 return $wgWikiID;
3123         } elseif ( $wgDBprefix ) {
3124                 return "$wgDBname-$wgDBprefix";
3125         } else {
3126                 return $wgDBname;
3127         }
3128 }
3129
3130 /**
3131  * Split a wiki ID into DB name and table prefix
3132  *
3133  * @param $wiki String
3134  *
3135  * @return array
3136  */
3137 function wfSplitWikiID( $wiki ) {
3138         $bits = explode( '-', $wiki, 2 );
3139         if ( count( $bits ) < 2 ) {
3140                 $bits[] = '';
3141         }
3142         return $bits;
3143 }
3144
3145 /**
3146  * Get a Database object.
3147  *
3148  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3149  *            master (for write queries), DB_SLAVE for potentially lagged read
3150  *            queries, or an integer >= 0 for a particular server.
3151  *
3152  * @param $groups Mixed: query groups. An array of group names that this query
3153  *                belongs to. May contain a single string if the query is only
3154  *                in one group.
3155  *
3156  * @param $wiki String: the wiki ID, or false for the current wiki
3157  *
3158  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3159  * will always return the same object, unless the underlying connection or load
3160  * balancer is manually destroyed.
3161  *
3162  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3163  * updater to ensure that a proper database is being updated.
3164  *
3165  * @return DatabaseBase
3166  */
3167 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3168         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3169 }
3170
3171 /**
3172  * Get a load balancer object.
3173  *
3174  * @param $wiki String: wiki ID, or false for the current wiki
3175  * @return LoadBalancer
3176  */
3177 function wfGetLB( $wiki = false ) {
3178         return wfGetLBFactory()->getMainLB( $wiki );
3179 }
3180
3181 /**
3182  * Get the load balancer factory object
3183  *
3184  * @return LBFactory
3185  */
3186 function &wfGetLBFactory() {
3187         return LBFactory::singleton();
3188 }
3189
3190 /**
3191  * Find a file.
3192  * Shortcut for RepoGroup::singleton()->findFile()
3193  *
3194  * @param $title String or Title object
3195  * @param $options Associative array of options:
3196  *     time:           requested time for an archived image, or false for the
3197  *                     current version. An image object will be returned which was
3198  *                     created at the specified time.
3199  *
3200  *     ignoreRedirect: If true, do not follow file redirects
3201  *
3202  *     private:        If true, return restricted (deleted) files if the current
3203  *                     user is allowed to view them. Otherwise, such files will not
3204  *                     be found.
3205  *
3206  *     bypassCache:    If true, do not use the process-local cache of File objects
3207  *
3208  * @return File, or false if the file does not exist
3209  */
3210 function wfFindFile( $title, $options = array() ) {
3211         return RepoGroup::singleton()->findFile( $title, $options );
3212 }
3213
3214 /**
3215  * Get an object referring to a locally registered file.
3216  * Returns a valid placeholder object if the file does not exist.
3217  *
3218  * @param $title Title or String
3219  * @return File, or null if passed an invalid Title
3220  */
3221 function wfLocalFile( $title ) {
3222         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3223 }
3224
3225 /**
3226  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3227  * @deprecated since 1.19
3228  */
3229 function wfStreamFile( $fname, $headers = array() ) {
3230         StreamFile::stream( $fname, $headers );
3231 }
3232
3233 /**
3234  * Should low-performance queries be disabled?
3235  *
3236  * @return Boolean
3237  * @codeCoverageIgnore
3238  */
3239 function wfQueriesMustScale() {
3240         global $wgMiserMode;
3241         return $wgMiserMode
3242                 || ( SiteStats::pages() > 100000
3243                 && SiteStats::edits() > 1000000
3244                 && SiteStats::users() > 10000 );
3245 }
3246
3247 /**
3248  * Get the path to a specified script file, respecting file
3249  * extensions; this is a wrapper around $wgScriptExtension etc.
3250  *
3251  * @param $script String: script filename, sans extension
3252  * @return String
3253  */
3254 function wfScript( $script = 'index' ) {
3255         global $wgScriptPath, $wgScriptExtension;
3256         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3257 }
3258
3259 /**
3260  * Get the script URL.
3261  *
3262  * @return script URL
3263  */
3264 function wfGetScriptUrl() {
3265         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3266                 #
3267                 # as it was called, minus the query string.
3268                 #
3269                 # Some sites use Apache rewrite rules to handle subdomains,
3270                 # and have PHP set up in a weird way that causes PHP_SELF
3271                 # to contain the rewritten URL instead of the one that the
3272                 # outside world sees.
3273                 #
3274                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3275                 # provides containing the "before" URL.
3276                 return $_SERVER['SCRIPT_NAME'];
3277         } else {
3278                 return $_SERVER['URL'];
3279         }
3280 }
3281
3282 /**
3283  * Convenience function converts boolean values into "true"
3284  * or "false" (string) values
3285  *
3286  * @param $value Boolean
3287  * @return String
3288  */
3289 function wfBoolToStr( $value ) {
3290         return $value ? 'true' : 'false';
3291 }
3292
3293 /**
3294  * Load an extension messages file
3295  *
3296  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3297  * @codeCoverageIgnore
3298  */
3299 function wfLoadExtensionMessages() {
3300         wfDeprecated( __FUNCTION__ );
3301 }
3302
3303 /**
3304  * Get a platform-independent path to the null file, e.g. /dev/null
3305  *
3306  * @return string
3307  */
3308 function wfGetNull() {
3309         return wfIsWindows()
3310                 ? 'NUL'
3311                 : '/dev/null';
3312 }
3313
3314 /**
3315  * Throws a warning that $function is deprecated
3316  *
3317  * @param $function String
3318  * @param $version String
3319  * @return null
3320  */
3321 function wfDeprecated( $function, $version = false ) {
3322         static $functionsWarned = array();
3323         if ( !isset( $functionsWarned[$function] ) ) {
3324                 $functionsWarned[$function] = true;
3325                 if ( $version ) {
3326                         global $wgDeprecationReleaseLimit;
3327                         if ( $wgDeprecationReleaseLimit ) {
3328                                 # Strip -* off the end of $version so that branches can use the
3329                                 # format #.##-branchname to avoid issues if the branch is merged into
3330                                 # a version of MediaWiki later than what it was branched from
3331                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
3332                                 # If the comparableVersion is larger than our release limit then
3333                                 # skip the warning message for the deprecation
3334                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
3335                                         return;
3336                                 }
3337                         }
3338                         wfWarn( "Use of $function was deprecated in $version.", 2 );
3339                 } else {
3340                         wfWarn( "Use of $function is deprecated.", 2 );
3341                 }
3342         }
3343 }
3344
3345 /**
3346  * Send a warning either to the debug log or in a PHP error depending on
3347  * $wgDevelopmentWarnings
3348  *
3349  * @param $msg String: message to send
3350  * @param $callerOffset Integer: number of items to go back in the backtrace to
3351  *        find the correct caller (1 = function calling wfWarn, ...)
3352  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3353  *        is true
3354  */
3355 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3356         global $wgDevelopmentWarnings;
3357
3358         $callers = wfDebugBacktrace();
3359         if ( isset( $callers[$callerOffset + 1] ) ) {
3360                 $callerfunc = $callers[$callerOffset + 1];
3361                 $callerfile = $callers[$callerOffset];
3362                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3363                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3364                 } else {
3365                         $file = '(internal function)';
3366                 }
3367                 $func = '';
3368                 if ( isset( $callerfunc['class'] ) ) {
3369                         $func .= $callerfunc['class'] . '::';
3370                 }
3371                 if ( isset( $callerfunc['function'] ) ) {
3372                         $func .= $callerfunc['function'];
3373                 }
3374                 $msg .= " [Called from $func in $file]";
3375         }
3376
3377         if ( $wgDevelopmentWarnings ) {
3378                 trigger_error( $msg, $level );
3379         } else {
3380                 wfDebug( "$msg\n" );
3381         }
3382 }
3383
3384 /**
3385  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3386  * and waiting for it to go down, this waits for the slaves to catch up to the
3387  * master position. Use this when updating very large numbers of rows, as
3388  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3389  * a no-op if there are no slaves.
3390  *
3391  * @param $maxLag Integer (deprecated)
3392  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3393  */
3394 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3395         $lb = wfGetLB( $wiki );
3396         // bug 27975 - Don't try to wait for slaves if there are none
3397         // Prevents permission error when getting master position
3398         if ( $lb->getServerCount() > 1 ) {
3399                 $dbw = $lb->getConnection( DB_MASTER );
3400                 $pos = $dbw->getMasterPos();
3401                 $lb->waitForAll( $pos );
3402         }
3403 }
3404
3405 /**
3406  * Used to be used for outputting text in the installer/updater
3407  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3408  */
3409 function wfOut( $s ) {
3410         wfDeprecated( __METHOD__ );
3411         global $wgCommandLineMode;
3412         if ( $wgCommandLineMode ) {
3413                 echo $s;
3414         } else {
3415                 echo htmlspecialchars( $s );
3416         }
3417         flush();
3418 }
3419
3420 /**
3421  * Count down from $n to zero on the terminal, with a one-second pause
3422  * between showing each number. For use in command-line scripts.
3423  * @codeCoverageIgnore
3424  * @param $n int
3425  */
3426 function wfCountDown( $n ) {
3427         for ( $i = $n; $i >= 0; $i-- ) {
3428                 if ( $i != $n ) {
3429                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3430                 }
3431                 echo $i;
3432                 flush();
3433                 if ( $i ) {
3434                         sleep( 1 );
3435                 }
3436         }
3437         echo "\n";
3438 }
3439
3440 /**
3441  * Generate a random 32-character hexadecimal token.
3442  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3443  *              characters before hashing.
3444  * @return string
3445  * @codeCoverageIgnore
3446  */
3447 function wfGenerateToken( $salt = '' ) {
3448         $salt = serialize( $salt );
3449         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3450 }
3451
3452 /**
3453  * Replace all invalid characters with -
3454  *
3455  * @param $name Mixed: filename to process
3456  * @return String
3457  */
3458 function wfStripIllegalFilenameChars( $name ) {
3459         global $wgIllegalFileChars;
3460         $name = wfBaseName( $name );
3461         $name = preg_replace(
3462                 "/[^" . Title::legalChars() . "]" .
3463                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3464                         "/",
3465                 '-',
3466                 $name
3467         );
3468         return $name;
3469 }
3470
3471 /**
3472  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3473  *
3474  * @return Integer value memory was set to.
3475  */
3476 function wfMemoryLimit() {
3477         global $wgMemoryLimit;
3478         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3479         if( $memlimit != -1 ) {
3480                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3481                 if( $conflimit == -1 ) {
3482                         wfDebug( "Removing PHP's memory limit\n" );
3483                         wfSuppressWarnings();
3484                         ini_set( 'memory_limit', $conflimit );
3485                         wfRestoreWarnings();
3486                         return $conflimit;
3487                 } elseif ( $conflimit > $memlimit ) {
3488                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3489                         wfSuppressWarnings();
3490                         ini_set( 'memory_limit', $conflimit );
3491                         wfRestoreWarnings();
3492                         return $conflimit;
3493                 }
3494         }
3495         return $memlimit;
3496 }
3497
3498 /**
3499  * Converts shorthand byte notation to integer form
3500  *
3501  * @param $string String
3502  * @return Integer
3503  */
3504 function wfShorthandToInteger( $string = '' ) {
3505         $string = trim( $string );
3506         if( $string === '' ) {
3507                 return -1;
3508         }
3509         $last = $string[strlen( $string ) - 1];
3510         $val = intval( $string );
3511         switch( $last ) {
3512                 case 'g':
3513                 case 'G':
3514                         $val *= 1024;
3515                         // break intentionally missing
3516                 case 'm':
3517                 case 'M':
3518                         $val *= 1024;
3519                         // break intentionally missing
3520                 case 'k':
3521                 case 'K':
3522                         $val *= 1024;
3523         }
3524
3525         return $val;
3526 }
3527
3528 /**
3529  * Get the normalised IETF language tag
3530  * See unit test for examples.
3531  *
3532  * @param $code String: The language code.
3533  * @return String: The language code which complying with BCP 47 standards.
3534  */
3535 function wfBCP47( $code ) {
3536         $codeSegment = explode( '-', $code );
3537         $codeBCP = array();
3538         foreach ( $codeSegment as $segNo => $seg ) {
3539                 if ( count( $codeSegment ) > 0 ) {
3540                         // when previous segment is x, it is a private segment and should be lc
3541                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3542                                 $codeBCP[$segNo] = strtolower( $seg );
3543                         // ISO 3166 country code
3544                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3545                                 $codeBCP[$segNo] = strtoupper( $seg );
3546                         // ISO 15924 script code
3547                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3548                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3549                         // Use lowercase for other cases
3550                         } else {
3551                                 $codeBCP[$segNo] = strtolower( $seg );
3552                         }
3553                 } else {
3554                 // Use lowercase for single segment
3555                         $codeBCP[$segNo] = strtolower( $seg );
3556                 }
3557         }
3558         $langCode = implode( '-', $codeBCP );
3559         return $langCode;
3560 }
3561
3562 /**
3563  * Get a cache object.
3564  *
3565  * @param $inputType integer Cache type, one the the CACHE_* constants.
3566  * @return BagOStuff
3567  */
3568 function wfGetCache( $inputType ) {
3569         return ObjectCache::getInstance( $inputType );
3570 }
3571
3572 /**
3573  * Get the main cache object
3574  *
3575  * @return BagOStuff
3576  */
3577 function wfGetMainCache() {
3578         global $wgMainCacheType;
3579         return ObjectCache::getInstance( $wgMainCacheType );
3580 }
3581
3582 /**
3583  * Get the cache object used by the message cache
3584  *
3585  * @return BagOStuff
3586  */
3587 function wfGetMessageCacheStorage() {
3588         global $wgMessageCacheType;
3589         return ObjectCache::getInstance( $wgMessageCacheType );
3590 }
3591
3592 /**
3593  * Get the cache object used by the parser cache
3594  *
3595  * @return BagOStuff
3596  */
3597 function wfGetParserCacheStorage() {
3598         global $wgParserCacheType;
3599         return ObjectCache::getInstance( $wgParserCacheType );
3600 }
3601
3602 /**
3603  * Call hook functions defined in $wgHooks
3604  *
3605  * @param $event String: event name
3606  * @param $args Array: parameters passed to hook functions
3607  * @return Boolean
3608  */
3609 function wfRunHooks( $event, $args = array() ) {
3610         return Hooks::run( $event, $args );
3611 }
3612
3613 /**
3614  * Wrapper around php's unpack.
3615  *
3616  * @param $format String: The format string (See php's docs)
3617  * @param $data: A binary string of binary data
3618  * @param $length integer or false: The minimun length of $data. This is to
3619  *      prevent reading beyond the end of $data. false to disable the check.
3620  *
3621  * Also be careful when using this function to read unsigned 32 bit integer
3622  * because php might make it negative.
3623  *
3624  * @throws MWException if $data not long enough, or if unpack fails
3625  * @return Associative array of the extracted data
3626  */
3627 function wfUnpack( $format, $data, $length=false ) {
3628         if ( $length !== false ) {
3629                 $realLen = strlen( $data );
3630                 if ( $realLen < $length ) {
3631                         throw new MWException( "Tried to use wfUnpack on a "
3632                                 . "string of length $realLen, but needed one "
3633                                 . "of at least length $length."
3634                         );
3635                 }
3636         }
3637
3638         wfSuppressWarnings();
3639         $result = unpack( $format, $data );
3640         wfRestoreWarnings();
3641
3642         if ( $result === false ) {
3643                 // If it cannot extract the packed data.
3644                 throw new MWException( "unpack could not unpack binary data" );
3645         }
3646         return $result;
3647 }