includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 if ( !defined( 'MEDIAWIKI' ) ) {
  24         die( "This file is part of MediaWiki, it is not a valid entry point" );
  25 }
  26
  27 use Liuggio\StatsdClient\Sender\SocketSender;
  28 use MediaWiki\Logger\LoggerFactory;
  29
  30 // Hide compatibility functions from Doxygen
  31 /// @cond
  32
  33 /**
  34  * Compatibility functions
  35  *
  36  * We support PHP 5.3.3 and up.
  37  * Re-implementations of newer functions or functions in non-standard
  38  * PHP extensions may be included here.
  39  */
  40
  41 if ( !function_exists( 'mb_substr' ) ) {
  42         /**
  43          * @codeCoverageIgnore
  44          * @see Fallback::mb_substr
  45          * @return string
  46          */
  47         function mb_substr( $str, $start, $count = 'end' ) {
  48                 return Fallback::mb_substr( $str, $start, $count );
  49         }
  50
  51         /**
  52          * @codeCoverageIgnore
  53          * @see Fallback::mb_substr_split_unicode
  54          * @return int
  55          */
  56         function mb_substr_split_unicode( $str, $splitPos ) {
  57                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  58         }
  59 }
  60
  61 if ( !function_exists( 'mb_strlen' ) ) {
  62         /**
  63          * @codeCoverageIgnore
  64          * @see Fallback::mb_strlen
  65          * @return int
  66          */
  67         function mb_strlen( $str, $enc = '' ) {
  68                 return Fallback::mb_strlen( $str, $enc );
  69         }
  70 }
  71
  72 if ( !function_exists( 'mb_strpos' ) ) {
  73         /**
  74          * @codeCoverageIgnore
  75          * @see Fallback::mb_strpos
  76          * @return int
  77          */
  78         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  79                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  80         }
  81 }
  82
  83 if ( !function_exists( 'mb_strrpos' ) ) {
  84         /**
  85          * @codeCoverageIgnore
  86          * @see Fallback::mb_strrpos
  87          * @return int
  88          */
  89         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  90                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  91         }
  92 }
  93
  94 // gzdecode function only exists in PHP >= 5.4.0
  95 // http://php.net/gzdecode
  96 if ( !function_exists( 'gzdecode' ) ) {
  97         /**
  98          * @codeCoverageIgnore
  99          * @param string $data
 100          * @return string
 101          */
 102         function gzdecode( $data ) {
 103                 return gzinflate( substr( $data, 10, -8 ) );
 104         }
 105 }
 106
 107 // hash_equals function only exists in PHP >= 5.6.0
 108 // http://php.net/hash_equals
 109 if ( !function_exists( 'hash_equals' ) ) {
 110         /**
 111          * Check whether a user-provided string is equal to a fixed-length secret string
 112          * without revealing bytes of the secret string through timing differences.
 113          *
 114          * The usual way to compare strings (PHP's === operator or the underlying memcmp()
 115          * function in C) is to compare corresponding bytes and stop at the first difference,
 116          * which would take longer for a partial match than for a complete mismatch. This
 117          * is not secure when one of the strings (e.g. an HMAC or token) must remain secret
 118          * and the other may come from an attacker. Statistical analysis of timing measurements
 119          * over many requests may allow the attacker to guess the string's bytes one at a time
 120          * (and check his guesses) even if the timing differences are extremely small.
 121          *
 122          * When making such a security-sensitive comparison, it is essential that the sequence
 123          * in which instructions are executed and memory locations are accessed not depend on
 124          * the secret string's value. HOWEVER, for simplicity, we do not attempt to minimize
 125          * the inevitable leakage of the string's length. That is generally known anyway as
 126          * a chararacteristic of the hash function used to compute the secret value.
 127          *
 128          * Longer explanation: http://www.emerose.com/timing-attacks-explained
 129          *
 130          * @codeCoverageIgnore
 131          * @param string $known_string Fixed-length secret string to compare against
 132          * @param string $user_string User-provided string
 133          * @return bool True if the strings are the same, false otherwise
 134          */
 135         function hash_equals( $known_string, $user_string ) {
 136                 // Strict type checking as in PHP's native implementation
 137                 if ( !is_string( $known_string ) ) {
 138                         trigger_error( 'hash_equals(): Expected known_string to be a string, ' .
 139                                 gettype( $known_string ) . ' given', E_USER_WARNING );
 140
 141                         return false;
 142                 }
 143
 144                 if ( !is_string( $user_string ) ) {
 145                         trigger_error( 'hash_equals(): Expected user_string to be a string, ' .
 146                                 gettype( $user_string ) . ' given', E_USER_WARNING );
 147
 148                         return false;
 149                 }
 150
 151                 $known_string_len = strlen( $known_string );
 152                 if ( $known_string_len !== strlen( $user_string ) ) {
 153                         return false;
 154                 }
 155
 156                 $result = 0;
 157                 for ( $i = 0; $i < $known_string_len; $i++ ) {
 158                         $result |= ord( $known_string[$i] ) ^ ord( $user_string[$i] );
 159                 }
 160
 161                 return ( $result === 0 );
 162         }
 163 }
 164 /// @endcond
 165
 166 /**
 167  * Load an extension
 168  *
 169  * This queues an extension to be loaded through
 170  * the ExtensionRegistry system.
 171  *
 172  * @param string $ext Name of the extension to load
 173  * @param string|null $path Absolute path of where to find the extension.json file
 174  * @since 1.25
 175  */
 176 function wfLoadExtension( $ext, $path = null ) {
 177         if ( !$path ) {
 178                 global $wgExtensionDirectory;
 179                 $path = "$wgExtensionDirectory/$ext/extension.json";
 180         }
 181         ExtensionRegistry::getInstance()->queue( $path );
 182 }
 183
 184 /**
 185  * Load multiple extensions at once
 186  *
 187  * Same as wfLoadExtension, but more efficient if you
 188  * are loading multiple extensions.
 189  *
 190  * If you want to specify custom paths, you should interact with
 191  * ExtensionRegistry directly.
 192  *
 193  * @see wfLoadExtension
 194  * @param string[] $exts Array of extension names to load
 195  * @since 1.25
 196  */
 197 function wfLoadExtensions( array $exts ) {
 198         global $wgExtensionDirectory;
 199         $registry = ExtensionRegistry::getInstance();
 200         foreach ( $exts as $ext ) {
 201                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
 202         }
 203 }
 204
 205 /**
 206  * Load a skin
 207  *
 208  * @see wfLoadExtension
 209  * @param string $skin Name of the extension to load
 210  * @param string|null $path Absolute path of where to find the skin.json file
 211  * @since 1.25
 212  */
 213 function wfLoadSkin( $skin, $path = null ) {
 214         if ( !$path ) {
 215                 global $wgStyleDirectory;
 216                 $path = "$wgStyleDirectory/$skin/skin.json";
 217         }
 218         ExtensionRegistry::getInstance()->queue( $path );
 219 }
 220
 221 /**
 222  * Load multiple skins at once
 223  *
 224  * @see wfLoadExtensions
 225  * @param string[] $skins Array of extension names to load
 226  * @since 1.25
 227  */
 228 function wfLoadSkins( array $skins ) {
 229         global $wgStyleDirectory;
 230         $registry = ExtensionRegistry::getInstance();
 231         foreach ( $skins as $skin ) {
 232                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 233         }
 234 }
 235
 236 /**
 237  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 238  * @param array $a
 239  * @param array $b
 240  * @return array
 241  */
 242 function wfArrayDiff2( $a, $b ) {
 243         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 244 }
 245
 246 /**
 247  * @param array|string $a
 248  * @param array|string $b
 249  * @return int
 250  */
 251 function wfArrayDiff2_cmp( $a, $b ) {
 252         if ( is_string( $a ) && is_string( $b ) ) {
 253                 return strcmp( $a, $b );
 254         } elseif ( count( $a ) !== count( $b ) ) {
 255                 return count( $a ) < count( $b ) ? -1 : 1;
 256         } else {
 257                 reset( $a );
 258                 reset( $b );
 259                 while ( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 260                         $cmp = strcmp( $valueA, $valueB );
 261                         if ( $cmp !== 0 ) {
 262                                 return $cmp;
 263                         }
 264                 }
 265                 return 0;
 266         }
 267 }
 268
 269 /**
 270  * Appends to second array if $value differs from that in $default
 271  *
 272  * @param string|int $key
 273  * @param mixed $value
 274  * @param mixed $default
 275  * @param array $changed Array to alter
 276  * @throws MWException
 277  */
 278 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 279         if ( is_null( $changed ) ) {
 280                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 281         }
 282         if ( $default[$key] !== $value ) {
 283                 $changed[$key] = $value;
 284         }
 285 }
 286
 287 /**
 288  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 289  * e.g.
 290  *      wfMergeErrorArrays(
 291  *              array( array( 'x' ) ),
 292  *              array( array( 'x', '2' ) ),
 293  *              array( array( 'x' ) ),
 294  *              array( array( 'y' ) )
 295  *      );
 296  * returns:
 297  *              array(
 298  *              array( 'x', '2' ),
 299  *              array( 'x' ),
 300  *              array( 'y' )
 301  *      )
 302  *
 303  * @param array $array1,...
 304  * @return array
 305  */
 306 function wfMergeErrorArrays( /*...*/ ) {
 307         $args = func_get_args();
 308         $out = array();
 309         foreach ( $args as $errors ) {
 310                 foreach ( $errors as $params ) {
 311                         $originalParams = $params;
 312                         if ( $params[0] instanceof MessageSpecifier ) {
 313                                 $msg = $params[0];
 314                                 $params = array_merge( array( $msg->getKey() ), $msg->getParams() );
 315                         }
 316                         # @todo FIXME: Sometimes get nested arrays for $params,
 317                         # which leads to E_NOTICEs
 318                         $spec = implode( "\t", $params );
 319                         $out[$spec] = $originalParams;
 320                 }
 321         }
 322         return array_values( $out );
 323 }
 324
 325 /**
 326  * Insert array into another array after the specified *KEY*
 327  *
 328  * @param array $array The array.
 329  * @param array $insert The array to insert.
 330  * @param mixed $after The key to insert after
 331  * @return array
 332  */
 333 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 334         // Find the offset of the element to insert after.
 335         $keys = array_keys( $array );
 336         $offsetByKey = array_flip( $keys );
 337
 338         $offset = $offsetByKey[$after];
 339
 340         // Insert at the specified offset
 341         $before = array_slice( $array, 0, $offset + 1, true );
 342         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 343
 344         $output = $before + $insert + $after;
 345
 346         return $output;
 347 }
 348
 349 /**
 350  * Recursively converts the parameter (an object) to an array with the same data
 351  *
 352  * @param object|array $objOrArray
 353  * @param bool $recursive
 354  * @return array
 355  */
 356 function wfObjectToArray( $objOrArray, $recursive = true ) {
 357         $array = array();
 358         if ( is_object( $objOrArray ) ) {
 359                 $objOrArray = get_object_vars( $objOrArray );
 360         }
 361         foreach ( $objOrArray as $key => $value ) {
 362                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 363                         $value = wfObjectToArray( $value );
 364                 }
 365
 366                 $array[$key] = $value;
 367         }
 368
 369         return $array;
 370 }
 371
 372 /**
 373  * Get a random decimal value between 0 and 1, in a way
 374  * not likely to give duplicate values for any realistic
 375  * number of articles.
 376  *
 377  * @note This is designed for use in relation to Special:RandomPage
 378  *       and the page_random database field.
 379  *
 380  * @return string
 381  */
 382 function wfRandom() {
 383         // The maximum random value is "only" 2^31-1, so get two random
 384         // values to reduce the chance of dupes
 385         $max = mt_getrandmax() + 1;
 386         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 387         return $rand;
 388 }
 389
 390 /**
 391  * Get a random string containing a number of pseudo-random hex characters.
 392  *
 393  * @note This is not secure, if you are trying to generate some sort
 394  *       of token please use MWCryptRand instead.
 395  *
 396  * @param int $length The length of the string to generate
 397  * @return string
 398  * @since 1.20
 399  */
 400 function wfRandomString( $length = 32 ) {
 401         $str = '';
 402         for ( $n = 0; $n < $length; $n += 7 ) {
 403                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 404         }
 405         return substr( $str, 0, $length );
 406 }
 407
 408 /**
 409  * We want some things to be included as literal characters in our title URLs
 410  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 411  * all of the following should be safe:
 412  *
 413  * ;:@&=$-_.+!*'(),
 414  *
 415  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 416  * character which should not be encoded. More importantly, google chrome
 417  * always converts %7E back to ~, and converting it in this function can
 418  * cause a redirect loop (T105265).
 419  *
 420  * But + is not safe because it's used to indicate a space; &= are only safe in
 421  * paths and not in queries (and we don't distinguish here); ' seems kind of
 422  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 423  * is reserved, we don't care.  So the list we unescape is:
 424  *
 425  * ;:@$!*(),/~
 426  *
 427  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 428  * so no fancy : for IIS7.
 429  *
 430  * %2F in the page titles seems to fatally break for some reason.
 431  *
 432  * @param string $s
 433  * @return string
 434  */
 435 function wfUrlencode( $s ) {
 436         static $needle;
 437
 438         if ( is_null( $s ) ) {
 439                 $needle = null;
 440                 return '';
 441         }
 442
 443         if ( is_null( $needle ) ) {
 444                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' );
 445                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 446                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 447                 ) {
 448                         $needle[] = '%3A';
 449                 }
 450         }
 451
 452         $s = urlencode( $s );
 453         $s = str_ireplace(
 454                 $needle,
 455                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ),
 456                 $s
 457         );
 458
 459         return $s;
 460 }
 461
 462 /**
 463  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 464  * "days=7&limit=100". Options in the first array override options in the second.
 465  * Options set to null or false will not be output.
 466  *
 467  * @param array $array1 ( String|Array )
 468  * @param array|null $array2 ( String|Array )
 469  * @param string $prefix
 470  * @return string
 471  */
 472 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 473         if ( !is_null( $array2 ) ) {
 474                 $array1 = $array1 + $array2;
 475         }
 476
 477         $cgi = '';
 478         foreach ( $array1 as $key => $value ) {
 479                 if ( !is_null( $value ) && $value !== false ) {
 480                         if ( $cgi != '' ) {
 481                                 $cgi .= '&';
 482                         }
 483                         if ( $prefix !== '' ) {
 484                                 $key = $prefix . "[$key]";
 485                         }
 486                         if ( is_array( $value ) ) {
 487                                 $firstTime = true;
 488                                 foreach ( $value as $k => $v ) {
 489                                         $cgi .= $firstTime ? '' : '&';
 490                                         if ( is_array( $v ) ) {
 491                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 492                                         } else {
 493                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 494                                         }
 495                                         $firstTime = false;
 496                                 }
 497                         } else {
 498                                 if ( is_object( $value ) ) {
 499                                         $value = $value->__toString();
 500                                 }
 501                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 502                         }
 503                 }
 504         }
 505         return $cgi;
 506 }
 507
 508 /**
 509  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 510  * its argument and returns the same string in array form.  This allows compatibility
 511  * with legacy functions that accept raw query strings instead of nice
 512  * arrays.  Of course, keys and values are urldecode()d.
 513  *
 514  * @param string $query Query string
 515  * @return string[] Array version of input
 516  */
 517 function wfCgiToArray( $query ) {
 518         if ( isset( $query[0] ) && $query[0] == '?' ) {
 519                 $query = substr( $query, 1 );
 520         }
 521         $bits = explode( '&', $query );
 522         $ret = array();
 523         foreach ( $bits as $bit ) {
 524                 if ( $bit === '' ) {
 525                         continue;
 526                 }
 527                 if ( strpos( $bit, '=' ) === false ) {
 528                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 529                         $key = $bit;
 530                         $value = '';
 531                 } else {
 532                         list( $key, $value ) = explode( '=', $bit );
 533                 }
 534                 $key = urldecode( $key );
 535                 $value = urldecode( $value );
 536                 if ( strpos( $key, '[' ) !== false ) {
 537                         $keys = array_reverse( explode( '[', $key ) );
 538                         $key = array_pop( $keys );
 539                         $temp = $value;
 540                         foreach ( $keys as $k ) {
 541                                 $k = substr( $k, 0, -1 );
 542                                 $temp = array( $k => $temp );
 543                         }
 544                         if ( isset( $ret[$key] ) ) {
 545                                 $ret[$key] = array_merge( $ret[$key], $temp );
 546                         } else {
 547                                 $ret[$key] = $temp;
 548                         }
 549                 } else {
 550                         $ret[$key] = $value;
 551                 }
 552         }
 553         return $ret;
 554 }
 555
 556 /**
 557  * Append a query string to an existing URL, which may or may not already
 558  * have query string parameters already. If so, they will be combined.
 559  *
 560  * @param string $url
 561  * @param string|string[] $query String or associative array
 562  * @return string
 563  */
 564 function wfAppendQuery( $url, $query ) {
 565         if ( is_array( $query ) ) {
 566                 $query = wfArrayToCgi( $query );
 567         }
 568         if ( $query != '' ) {
 569                 if ( false === strpos( $url, '?' ) ) {
 570                         $url .= '?';
 571                 } else {
 572                         $url .= '&';
 573                 }
 574                 $url .= $query;
 575         }
 576         return $url;
 577 }
 578
 579 /**
 580  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 581  * is correct.
 582  *
 583  * The meaning of the PROTO_* constants is as follows:
 584  * PROTO_HTTP: Output a URL starting with http://
 585  * PROTO_HTTPS: Output a URL starting with https://
 586  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 587  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 588  *    on which protocol was used for the current incoming request
 589  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 590  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 591  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 592  *
 593  * @todo this won't work with current-path-relative URLs
 594  * like "subdir/foo.html", etc.
 595  *
 596  * @param string $url Either fully-qualified or a local path + query
 597  * @param string $defaultProto One of the PROTO_* constants. Determines the
 598  *    protocol to use if $url or $wgServer is protocol-relative
 599  * @return string Fully-qualified URL, current-path-relative URL or false if
 600  *    no valid URL can be constructed
 601  */
 602 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 603         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 604                 $wgHttpsPort;
 605         if ( $defaultProto === PROTO_CANONICAL ) {
 606                 $serverUrl = $wgCanonicalServer;
 607         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 608                 // Make $wgInternalServer fall back to $wgServer if not set
 609                 $serverUrl = $wgInternalServer;
 610         } else {
 611                 $serverUrl = $wgServer;
 612                 if ( $defaultProto === PROTO_CURRENT ) {
 613                         $defaultProto = $wgRequest->getProtocol() . '://';
 614                 }
 615         }
 616
 617         // Analyze $serverUrl to obtain its protocol
 618         $bits = wfParseUrl( $serverUrl );
 619         $serverHasProto = $bits && $bits['scheme'] != '';
 620
 621         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 622                 if ( $serverHasProto ) {
 623                         $defaultProto = $bits['scheme'] . '://';
 624                 } else {
 625                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 626                         // This really isn't supposed to happen. Fall back to HTTP in this
 627                         // ridiculous case.
 628                         $defaultProto = PROTO_HTTP;
 629                 }
 630         }
 631
 632         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 633
 634         if ( substr( $url, 0, 2 ) == '//' ) {
 635                 $url = $defaultProtoWithoutSlashes . $url;
 636         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 637                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 638                 // otherwise leave it alone.
 639                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 640         }
 641
 642         $bits = wfParseUrl( $url );
 643
 644         // ensure proper port for HTTPS arrives in URL
 645         // https://phabricator.wikimedia.org/T67184
 646         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 647                 $bits['port'] = $wgHttpsPort;
 648         }
 649
 650         if ( $bits && isset( $bits['path'] ) ) {
 651                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 652                 return wfAssembleUrl( $bits );
 653         } elseif ( $bits ) {
 654                 # No path to expand
 655                 return $url;
 656         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 657                 # URL is a relative path
 658                 return wfRemoveDotSegments( $url );
 659         }
 660
 661         # Expanded URL is not valid.
 662         return false;
 663 }
 664
 665 /**
 666  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 667  * if you need to edit part of a URL and put it back together.
 668  *
 669  * This is the basic structure used (brackets contain keys for $urlParts):
 670  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 671  *
 672  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 673  *
 674  * @since 1.19
 675  * @param array $urlParts URL parts, as output from wfParseUrl
 676  * @return string URL assembled from its component parts
 677  */
 678 function wfAssembleUrl( $urlParts ) {
 679         $result = '';
 680
 681         if ( isset( $urlParts['delimiter'] ) ) {
 682                 if ( isset( $urlParts['scheme'] ) ) {
 683                         $result .= $urlParts['scheme'];
 684                 }
 685
 686                 $result .= $urlParts['delimiter'];
 687         }
 688
 689         if ( isset( $urlParts['host'] ) ) {
 690                 if ( isset( $urlParts['user'] ) ) {
 691                         $result .= $urlParts['user'];
 692                         if ( isset( $urlParts['pass'] ) ) {
 693                                 $result .= ':' . $urlParts['pass'];
 694                         }
 695                         $result .= '@';
 696                 }
 697
 698                 $result .= $urlParts['host'];
 699
 700                 if ( isset( $urlParts['port'] ) ) {
 701                         $result .= ':' . $urlParts['port'];
 702                 }
 703         }
 704
 705         if ( isset( $urlParts['path'] ) ) {
 706                 $result .= $urlParts['path'];
 707         }
 708
 709         if ( isset( $urlParts['query'] ) ) {
 710                 $result .= '?' . $urlParts['query'];
 711         }
 712
 713         if ( isset( $urlParts['fragment'] ) ) {
 714                 $result .= '#' . $urlParts['fragment'];
 715         }
 716
 717         return $result;
 718 }
 719
 720 /**
 721  * Remove all dot-segments in the provided URL path.  For example,
 722  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 723  * RFC3986 section 5.2.4.
 724  *
 725  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 726  *
 727  * @param string $urlPath URL path, potentially containing dot-segments
 728  * @return string URL path with all dot-segments removed
 729  */
 730 function wfRemoveDotSegments( $urlPath ) {
 731         $output = '';
 732         $inputOffset = 0;
 733         $inputLength = strlen( $urlPath );
 734
 735         while ( $inputOffset < $inputLength ) {
 736                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 737                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 738                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 739                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 740                 $trimOutput = false;
 741
 742                 if ( $prefixLengthTwo == './' ) {
 743                         # Step A, remove leading "./"
 744                         $inputOffset += 2;
 745                 } elseif ( $prefixLengthThree == '../' ) {
 746                         # Step A, remove leading "../"
 747                         $inputOffset += 3;
 748                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 749                         # Step B, replace leading "/.$" with "/"
 750                         $inputOffset += 1;
 751                         $urlPath[$inputOffset] = '/';
 752                 } elseif ( $prefixLengthThree == '/./' ) {
 753                         # Step B, replace leading "/./" with "/"
 754                         $inputOffset += 2;
 755                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 756                         # Step C, replace leading "/..$" with "/" and
 757                         # remove last path component in output
 758                         $inputOffset += 2;
 759                         $urlPath[$inputOffset] = '/';
 760                         $trimOutput = true;
 761                 } elseif ( $prefixLengthFour == '/../' ) {
 762                         # Step C, replace leading "/../" with "/" and
 763                         # remove last path component in output
 764                         $inputOffset += 3;
 765                         $trimOutput = true;
 766                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 767                         # Step D, remove "^.$"
 768                         $inputOffset += 1;
 769                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 770                         # Step D, remove "^..$"
 771                         $inputOffset += 2;
 772                 } else {
 773                         # Step E, move leading path segment to output
 774                         if ( $prefixLengthOne == '/' ) {
 775                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 776                         } else {
 777                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 778                         }
 779                         if ( $slashPos === false ) {
 780                                 $output .= substr( $urlPath, $inputOffset );
 781                                 $inputOffset = $inputLength;
 782                         } else {
 783                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 784                                 $inputOffset += $slashPos - $inputOffset;
 785                         }
 786                 }
 787
 788                 if ( $trimOutput ) {
 789                         $slashPos = strrpos( $output, '/' );
 790                         if ( $slashPos === false ) {
 791                                 $output = '';
 792                         } else {
 793                                 $output = substr( $output, 0, $slashPos );
 794                         }
 795                 }
 796         }
 797
 798         return $output;
 799 }
 800
 801 /**
 802  * Returns a regular expression of url protocols
 803  *
 804  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 805  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 806  * @return string
 807  */
 808 function wfUrlProtocols( $includeProtocolRelative = true ) {
 809         global $wgUrlProtocols;
 810
 811         // Cache return values separately based on $includeProtocolRelative
 812         static $withProtRel = null, $withoutProtRel = null;
 813         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 814         if ( !is_null( $cachedValue ) ) {
 815                 return $cachedValue;
 816         }
 817
 818         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 819         // with LocalSettings files from 1.5
 820         if ( is_array( $wgUrlProtocols ) ) {
 821                 $protocols = array();
 822                 foreach ( $wgUrlProtocols as $protocol ) {
 823                         // Filter out '//' if !$includeProtocolRelative
 824                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 825                                 $protocols[] = preg_quote( $protocol, '/' );
 826                         }
 827                 }
 828
 829                 $retval = implode( '|', $protocols );
 830         } else {
 831                 // Ignore $includeProtocolRelative in this case
 832                 // This case exists for pre-1.6 compatibility, and we can safely assume
 833                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 834                 // URLs weren't supported until 1.18
 835                 $retval = $wgUrlProtocols;
 836         }
 837
 838         // Cache return value
 839         if ( $includeProtocolRelative ) {
 840                 $withProtRel = $retval;
 841         } else {
 842                 $withoutProtRel = $retval;
 843         }
 844         return $retval;
 845 }
 846
 847 /**
 848  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 849  * you need a regex that matches all URL protocols but does not match protocol-
 850  * relative URLs
 851  * @return string
 852  */
 853 function wfUrlProtocolsWithoutProtRel() {
 854         return wfUrlProtocols( false );
 855 }
 856
 857 /**
 858  * parse_url() work-alike, but non-broken.  Differences:
 859  *
 860  * 1) Does not raise warnings on bad URLs (just returns false).
 861  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 862  *    protocol-relative URLs) correctly.
 863  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2)).
 864  *
 865  * @param string $url A URL to parse
 866  * @return string[] Bits of the URL in an associative array, per PHP docs
 867  */
 868 function wfParseUrl( $url ) {
 869         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 870
 871         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 872         // bad that the easiest way to handle them is to just prepend 'http:' and
 873         // strip the protocol out later.
 874         $wasRelative = substr( $url, 0, 2 ) == '//';
 875         if ( $wasRelative ) {
 876                 $url = "http:$url";
 877         }
 878         MediaWiki\suppressWarnings();
 879         $bits = parse_url( $url );
 880         MediaWiki\restoreWarnings();
 881         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 882         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 883         if ( !$bits || !isset( $bits['scheme'] ) ) {
 884                 return false;
 885         }
 886
 887         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 888         $bits['scheme'] = strtolower( $bits['scheme'] );
 889
 890         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 891         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 892                 $bits['delimiter'] = '://';
 893         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 894                 $bits['delimiter'] = ':';
 895                 // parse_url detects for news: and mailto: the host part of an url as path
 896                 // We have to correct this wrong detection
 897                 if ( isset( $bits['path'] ) ) {
 898                         $bits['host'] = $bits['path'];
 899                         $bits['path'] = '';
 900                 }
 901         } else {
 902                 return false;
 903         }
 904
 905         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 906         if ( !isset( $bits['host'] ) ) {
 907                 $bits['host'] = '';
 908
 909                 // bug 45069
 910                 if ( isset( $bits['path'] ) ) {
 911                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 912                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 913                                 $bits['path'] = '/' . $bits['path'];
 914                         }
 915                 } else {
 916                         $bits['path'] = '';
 917                 }
 918         }
 919
 920         // If the URL was protocol-relative, fix scheme and delimiter
 921         if ( $wasRelative ) {
 922                 $bits['scheme'] = '';
 923                 $bits['delimiter'] = '//';
 924         }
 925         return $bits;
 926 }
 927
 928 /**
 929  * Take a URL, make sure it's expanded to fully qualified, and replace any
 930  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 931  * for more compact display and legibility for local audiences.
 932  *
 933  * @todo handle punycode domains too
 934  *
 935  * @param string $url
 936  * @return string
 937  */
 938 function wfExpandIRI( $url ) {
 939         return preg_replace_callback(
 940                 '/((?:%[89A-F][0-9A-F])+)/i',
 941                 'wfExpandIRI_callback',
 942                 wfExpandUrl( $url )
 943         );
 944 }
 945
 946 /**
 947  * Private callback for wfExpandIRI
 948  * @param array $matches
 949  * @return string
 950  */
 951 function wfExpandIRI_callback( $matches ) {
 952         return urldecode( $matches[1] );
 953 }
 954
 955 /**
 956  * Make URL indexes, appropriate for the el_index field of externallinks.
 957  *
 958  * @param string $url
 959  * @return array
 960  */
 961 function wfMakeUrlIndexes( $url ) {
 962         $bits = wfParseUrl( $url );
 963
 964         // Reverse the labels in the hostname, convert to lower case
 965         // For emails reverse domainpart only
 966         if ( $bits['scheme'] == 'mailto' ) {
 967                 $mailparts = explode( '@', $bits['host'], 2 );
 968                 if ( count( $mailparts ) === 2 ) {
 969                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 970                 } else {
 971                         // No domain specified, don't mangle it
 972                         $domainpart = '';
 973                 }
 974                 $reversedHost = $domainpart . '@' . $mailparts[0];
 975         } else {
 976                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 977         }
 978         // Add an extra dot to the end
 979         // Why? Is it in wrong place in mailto links?
 980         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 981                 $reversedHost .= '.';
 982         }
 983         // Reconstruct the pseudo-URL
 984         $prot = $bits['scheme'];
 985         $index = $prot . $bits['delimiter'] . $reversedHost;
 986         // Leave out user and password. Add the port, path, query and fragment
 987         if ( isset( $bits['port'] ) ) {
 988                 $index .= ':' . $bits['port'];
 989         }
 990         if ( isset( $bits['path'] ) ) {
 991                 $index .= $bits['path'];
 992         } else {
 993                 $index .= '/';
 994         }
 995         if ( isset( $bits['query'] ) ) {
 996                 $index .= '?' . $bits['query'];
 997         }
 998         if ( isset( $bits['fragment'] ) ) {
 999                 $index .= '#' . $bits['fragment'];
1000         }
1001
1002         if ( $prot == '' ) {
1003                 return array( "http:$index", "https:$index" );
1004         } else {
1005                 return array( $index );
1006         }
1007 }
1008
1009 /**
1010  * Check whether a given URL has a domain that occurs in a given set of domains
1011  * @param string $url URL
1012  * @param array $domains Array of domains (strings)
1013  * @return bool True if the host part of $url ends in one of the strings in $domains
1014  */
1015 function wfMatchesDomainList( $url, $domains ) {
1016         $bits = wfParseUrl( $url );
1017         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1018                 $host = '.' . $bits['host'];
1019                 foreach ( (array)$domains as $domain ) {
1020                         $domain = '.' . $domain;
1021                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1022                                 return true;
1023                         }
1024                 }
1025         }
1026         return false;
1027 }
1028
1029 /**
1030  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1031  * In normal operation this is a NOP.
1032  *
1033  * Controlling globals:
1034  * $wgDebugLogFile - points to the log file
1035  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1036  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1037  *
1038  * @since 1.25 support for additional context data
1039  *
1040  * @param string $text
1041  * @param string|bool $dest Destination of the message:
1042  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1043  *     - 'private': excluded from HTML output
1044  *   For backward compatibility, it can also take a boolean:
1045  *     - true: same as 'all'
1046  *     - false: same as 'private'
1047  * @param array $context Additional logging context data
1048  */
1049 function wfDebug( $text, $dest = 'all', array $context = array() ) {
1050         global $wgDebugRawPage, $wgDebugLogPrefix;
1051         global $wgDebugTimestamps, $wgRequestTime;
1052
1053         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1054                 return;
1055         }
1056
1057         $text = trim( $text );
1058
1059         if ( $wgDebugTimestamps ) {
1060                 $context['seconds_elapsed'] = sprintf(
1061                         '%6.4f',
1062                         microtime( true ) - $wgRequestTime
1063                 );
1064                 $context['memory_used'] = sprintf(
1065                         '%5.1fM',
1066                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1067                 );
1068         }
1069
1070         if ( $wgDebugLogPrefix !== '' ) {
1071                 $context['prefix'] = $wgDebugLogPrefix;
1072         }
1073         $context['private'] = ( $dest === false || $dest === 'private' );
1074
1075         $logger = LoggerFactory::getInstance( 'wfDebug' );
1076         $logger->debug( $text, $context );
1077 }
1078
1079 /**
1080  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1081  * @return bool
1082  */
1083 function wfIsDebugRawPage() {
1084         static $cache;
1085         if ( $cache !== null ) {
1086                 return $cache;
1087         }
1088         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1089         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1090                 || (
1091                         isset( $_SERVER['SCRIPT_NAME'] )
1092                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1093                 )
1094         ) {
1095                 $cache = true;
1096         } else {
1097                 $cache = false;
1098         }
1099         return $cache;
1100 }
1101
1102 /**
1103  * Send a line giving PHP memory usage.
1104  *
1105  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1106  */
1107 function wfDebugMem( $exact = false ) {
1108         $mem = memory_get_usage();
1109         if ( !$exact ) {
1110                 $mem = floor( $mem / 1024 ) . ' KiB';
1111         } else {
1112                 $mem .= ' B';
1113         }
1114         wfDebug( "Memory usage: $mem\n" );
1115 }
1116
1117 /**
1118  * Send a line to a supplementary debug log file, if configured, or main debug
1119  * log if not.
1120  *
1121  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1122  * a string filename or an associative array mapping 'destination' to the
1123  * desired filename. The associative array may also contain a 'sample' key
1124  * with an integer value, specifying a sampling factor. Sampled log events
1125  * will be emitted with a 1 in N random chance.
1126  *
1127  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1128  * @since 1.25 support for additional context data
1129  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1130  *
1131  * @param string $logGroup
1132  * @param string $text
1133  * @param string|bool $dest Destination of the message:
1134  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1135  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1136  *       discarded otherwise
1137  *   For backward compatibility, it can also take a boolean:
1138  *     - true: same as 'all'
1139  *     - false: same as 'private'
1140  * @param array $context Additional logging context data
1141  */
1142 function wfDebugLog(
1143         $logGroup, $text, $dest = 'all', array $context = array()
1144 ) {
1145         $text = trim( $text );
1146
1147         $logger = LoggerFactory::getInstance( $logGroup );
1148         $context['private'] = ( $dest === false || $dest === 'private' );
1149         $logger->info( $text, $context );
1150 }
1151
1152 /**
1153  * Log for database errors
1154  *
1155  * @since 1.25 support for additional context data
1156  *
1157  * @param string $text Database error message.
1158  * @param array $context Additional logging context data
1159  */
1160 function wfLogDBError( $text, array $context = array() ) {
1161         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1162         $logger->error( trim( $text ), $context );
1163 }
1164
1165 /**
1166  * Throws a warning that $function is deprecated
1167  *
1168  * @param string $function
1169  * @param string|bool $version Version of MediaWiki that the function
1170  *    was deprecated in (Added in 1.19).
1171  * @param string|bool $component Added in 1.19.
1172  * @param int $callerOffset How far up the call stack is the original
1173  *    caller. 2 = function that called the function that called
1174  *    wfDeprecated (Added in 1.20)
1175  *
1176  * @return null
1177  */
1178 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1179         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1180 }
1181
1182 /**
1183  * Send a warning either to the debug log or in a PHP error depending on
1184  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1185  *
1186  * @param string $msg Message to send
1187  * @param int $callerOffset Number of items to go back in the backtrace to
1188  *        find the correct caller (1 = function calling wfWarn, ...)
1189  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1190  *        only used when $wgDevelopmentWarnings is true
1191  */
1192 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1193         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1194 }
1195
1196 /**
1197  * Send a warning as a PHP error and the debug log. This is intended for logging
1198  * warnings in production. For logging development warnings, use WfWarn instead.
1199  *
1200  * @param string $msg Message to send
1201  * @param int $callerOffset Number of items to go back in the backtrace to
1202  *        find the correct caller (1 = function calling wfLogWarning, ...)
1203  * @param int $level PHP error level; defaults to E_USER_WARNING
1204  */
1205 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1206         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1207 }
1208
1209 /**
1210  * Log to a file without getting "file size exceeded" signals.
1211  *
1212  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1213  * send lines to the specified port, prefixed by the specified prefix and a space.
1214  * @since 1.25 support for additional context data
1215  *
1216  * @param string $text
1217  * @param string $file Filename
1218  * @param array $context Additional logging context data
1219  * @throws MWException
1220  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1221  */
1222 function wfErrorLog( $text, $file, array $context = array() ) {
1223         wfDeprecated( __METHOD__, '1.25' );
1224         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1225         $context['destination'] = $file;
1226         $logger->info( trim( $text ), $context );
1227 }
1228
1229 /**
1230  * @todo document
1231  */
1232 function wfLogProfilingData() {
1233         global $wgDebugLogGroups, $wgDebugRawPage;
1234
1235         $context = RequestContext::getMain();
1236         $request = $context->getRequest();
1237
1238         $profiler = Profiler::instance();
1239         $profiler->setContext( $context );
1240         $profiler->logData();
1241
1242         $config = $context->getConfig();
1243         if ( $config->get( 'StatsdServer' ) ) {
1244                 try {
1245                         $statsdServer = explode( ':', $config->get( 'StatsdServer' ) );
1246                         $statsdHost = $statsdServer[0];
1247                         $statsdPort = isset( $statsdServer[1] ) ? $statsdServer[1] : 8125;
1248                         $statsdSender = new SocketSender( $statsdHost, $statsdPort );
1249                         $statsdClient = new SamplingStatsdClient( $statsdSender, true, false );
1250                         $statsdClient->send( $context->getStats()->getBuffer() );
1251                 } catch ( Exception $ex ) {
1252                         MWExceptionHandler::logException( $ex );
1253                 }
1254         }
1255
1256         # Profiling must actually be enabled...
1257         if ( $profiler instanceof ProfilerStub ) {
1258                 return;
1259         }
1260
1261         if ( isset( $wgDebugLogGroups['profileoutput'] )
1262                 && $wgDebugLogGroups['profileoutput'] === false
1263         ) {
1264                 // Explicitly disabled
1265                 return;
1266         }
1267         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1268                 return;
1269         }
1270
1271         $ctx = array( 'elapsed' => $request->getElapsedTime() );
1272         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1273                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1274         }
1275         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1276                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1277         }
1278         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1279                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1280         }
1281         if ( isset( $ctx['forwarded_for'] ) ||
1282                 isset( $ctx['client_ip'] ) ||
1283                 isset( $ctx['from'] ) ) {
1284                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1285         }
1286
1287         // Don't load $wgUser at this late stage just for statistics purposes
1288         // @todo FIXME: We can detect some anons even if it is not loaded.
1289         // See User::getId()
1290         $user = $context->getUser();
1291         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1292
1293         // Command line script uses a FauxRequest object which does not have
1294         // any knowledge about an URL and throw an exception instead.
1295         try {
1296                 $ctx['url'] = urldecode( $request->getRequestURL() );
1297         } catch ( Exception $ignored ) {
1298                 // no-op
1299         }
1300
1301         $ctx['output'] = $profiler->getOutput();
1302
1303         $log = LoggerFactory::getInstance( 'profileoutput' );
1304         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1305 }
1306
1307 /**
1308  * Increment a statistics counter
1309  *
1310  * @param string $key
1311  * @param int $count
1312  * @return void
1313  */
1314 function wfIncrStats( $key, $count = 1 ) {
1315         $stats = RequestContext::getMain()->getStats();
1316         $stats->updateCount( $key, $count );
1317 }
1318
1319 /**
1320  * Check whether the wiki is in read-only mode.
1321  *
1322  * @return bool
1323  */
1324 function wfReadOnly() {
1325         return wfReadOnlyReason() !== false;
1326 }
1327
1328 /**
1329  * Check if the site is in read-only mode and return the message if so
1330  *
1331  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1332  * for slave lag. This may result in DB_SLAVE connection being made.
1333  *
1334  * @return string|bool String when in read-only mode; false otherwise
1335  */
1336 function wfReadOnlyReason() {
1337         $readOnly = wfConfiguredReadOnlyReason();
1338         if ( $readOnly !== false ) {
1339                 return $readOnly;
1340         }
1341
1342         static $lbReadOnly = null;
1343         if ( $lbReadOnly === null ) {
1344                 // Callers use this method to be aware that data presented to a user
1345                 // may be very stale and thus allowing submissions can be problematic.
1346                 $lbReadOnly = wfGetLB()->getReadOnlyReason();
1347         }
1348
1349         return $lbReadOnly;
1350 }
1351
1352 /**
1353  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1354  *
1355  * @return string|bool String when in read-only mode; false otherwise
1356  * @since 1.27
1357  */
1358 function wfConfiguredReadOnlyReason() {
1359         global $wgReadOnly, $wgReadOnlyFile;
1360
1361         if ( $wgReadOnly === null ) {
1362                 // Set $wgReadOnly for faster access next time
1363                 if ( is_file( $wgReadOnlyFile ) && filesize( $wgReadOnlyFile ) > 0 ) {
1364                         $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1365                 } else {
1366                         $wgReadOnly = false;
1367                 }
1368         }
1369
1370         return $wgReadOnly;
1371 }
1372
1373 /**
1374  * Return a Language object from $langcode
1375  *
1376  * @param Language|string|bool $langcode Either:
1377  *                  - a Language object
1378  *                  - code of the language to get the message for, if it is
1379  *                    a valid code create a language for that language, if
1380  *                    it is a string but not a valid code then make a basic
1381  *                    language object
1382  *                  - a boolean: if it's false then use the global object for
1383  *                    the current user's language (as a fallback for the old parameter
1384  *                    functionality), or if it is true then use global object
1385  *                    for the wiki's content language.
1386  * @return Language
1387  */
1388 function wfGetLangObj( $langcode = false ) {
1389         # Identify which language to get or create a language object for.
1390         # Using is_object here due to Stub objects.
1391         if ( is_object( $langcode ) ) {
1392                 # Great, we already have the object (hopefully)!
1393                 return $langcode;
1394         }
1395
1396         global $wgContLang, $wgLanguageCode;
1397         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1398                 # $langcode is the language code of the wikis content language object.
1399                 # or it is a boolean and value is true
1400                 return $wgContLang;
1401         }
1402
1403         global $wgLang;
1404         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1405                 # $langcode is the language code of user language object.
1406                 # or it was a boolean and value is false
1407                 return $wgLang;
1408         }
1409
1410         $validCodes = array_keys( Language::fetchLanguageNames() );
1411         if ( in_array( $langcode, $validCodes ) ) {
1412                 # $langcode corresponds to a valid language.
1413                 return Language::factory( $langcode );
1414         }
1415
1416         # $langcode is a string, but not a valid language code; use content language.
1417         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1418         return $wgContLang;
1419 }
1420
1421 /**
1422  * This is the function for getting translated interface messages.
1423  *
1424  * @see Message class for documentation how to use them.
1425  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1426  *
1427  * This function replaces all old wfMsg* functions.
1428  *
1429  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1430  * @param mixed $params,... Normal message parameters
1431  * @return Message
1432  *
1433  * @since 1.17
1434  *
1435  * @see Message::__construct
1436  */
1437 function wfMessage( $key /*...*/ ) {
1438         $params = func_get_args();
1439         array_shift( $params );
1440         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1441                 $params = $params[0];
1442         }
1443         return new Message( $key, $params );
1444 }
1445
1446 /**
1447  * This function accepts multiple message keys and returns a message instance
1448  * for the first message which is non-empty. If all messages are empty then an
1449  * instance of the first message key is returned.
1450  *
1451  * @param string|string[] $keys,... Message keys
1452  * @return Message
1453  *
1454  * @since 1.18
1455  *
1456  * @see Message::newFallbackSequence
1457  */
1458 function wfMessageFallback( /*...*/ ) {
1459         $args = func_get_args();
1460         return call_user_func_array( 'Message::newFallbackSequence', $args );
1461 }
1462
1463 /**
1464  * Get a message from anywhere, for the current user language.
1465  *
1466  * Use wfMsgForContent() instead if the message should NOT
1467  * change depending on the user preferences.
1468  *
1469  * @deprecated since 1.18
1470  *
1471  * @param string $key Lookup key for the message, usually
1472  *    defined in languages/Language.php
1473  *
1474  * Parameters to the message, which can be used to insert variable text into
1475  * it, can be passed to this function in the following formats:
1476  * - One per argument, starting at the second parameter
1477  * - As an array in the second parameter
1478  * These are not shown in the function definition.
1479  *
1480  * @return string
1481  */
1482 function wfMsg( $key ) {
1483         wfDeprecated( __METHOD__, '1.21' );
1484
1485         $args = func_get_args();
1486         array_shift( $args );
1487         return wfMsgReal( $key, $args );
1488 }
1489
1490 /**
1491  * Same as above except doesn't transform the message
1492  *
1493  * @deprecated since 1.18
1494  *
1495  * @param string $key
1496  * @return string
1497  */
1498 function wfMsgNoTrans( $key ) {
1499         wfDeprecated( __METHOD__, '1.21' );
1500
1501         $args = func_get_args();
1502         array_shift( $args );
1503         return wfMsgReal( $key, $args, true, false, false );
1504 }
1505
1506 /**
1507  * Get a message from anywhere, for the current global language
1508  * set with $wgLanguageCode.
1509  *
1510  * Use this if the message should NOT change dependent on the
1511  * language set in the user's preferences. This is the case for
1512  * most text written into logs, as well as link targets (such as
1513  * the name of the copyright policy page). Link titles, on the
1514  * other hand, should be shown in the UI language.
1515  *
1516  * Note that MediaWiki allows users to change the user interface
1517  * language in their preferences, but a single installation
1518  * typically only contains content in one language.
1519  *
1520  * Be wary of this distinction: If you use wfMsg() where you should
1521  * use wfMsgForContent(), a user of the software may have to
1522  * customize potentially hundreds of messages in
1523  * order to, e.g., fix a link in every possible language.
1524  *
1525  * @deprecated since 1.18
1526  *
1527  * @param string $key Lookup key for the message, usually
1528  *     defined in languages/Language.php
1529  * @return string
1530  */
1531 function wfMsgForContent( $key ) {
1532         wfDeprecated( __METHOD__, '1.21' );
1533
1534         global $wgForceUIMsgAsContentMsg;
1535         $args = func_get_args();
1536         array_shift( $args );
1537         $forcontent = true;
1538         if ( is_array( $wgForceUIMsgAsContentMsg )
1539                 && in_array( $key, $wgForceUIMsgAsContentMsg )
1540         ) {
1541                 $forcontent = false;
1542         }
1543         return wfMsgReal( $key, $args, true, $forcontent );
1544 }
1545
1546 /**
1547  * Really get a message
1548  *
1549  * @deprecated since 1.18
1550  *
1551  * @param string $key Key to get.
1552  * @param array $args
1553  * @param bool $useDB
1554  * @param string|bool $forContent Language code, or false for user lang, true for content lang.
1555  * @param bool $transform Whether or not to transform the message.
1556  * @return string The requested message.
1557  */
1558 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1559         wfDeprecated( __METHOD__, '1.21' );
1560
1561         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1562         $message = wfMsgReplaceArgs( $message, $args );
1563         return $message;
1564 }
1565
1566 /**
1567  * Fetch a message string value, but don't replace any keys yet.
1568  *
1569  * @deprecated since 1.18
1570  *
1571  * @param string $key
1572  * @param bool $useDB
1573  * @param string|bool $langCode Code of the language to get the message for, or
1574  *   behaves as a content language switch if it is a boolean.
1575  * @param bool $transform Whether to parse magic words, etc.
1576  * @return string
1577  */
1578 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1579         wfDeprecated( __METHOD__, '1.21' );
1580
1581         Hooks::run( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1582
1583         $cache = MessageCache::singleton();
1584         $message = $cache->get( $key, $useDB, $langCode );
1585         if ( $message === false ) {
1586                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1587         } elseif ( $transform ) {
1588                 $message = $cache->transform( $message );
1589         }
1590         return $message;
1591 }
1592
1593 /**
1594  * Replace message parameter keys on the given formatted output.
1595  *
1596  * @param string $message
1597  * @param array $args
1598  * @return string
1599  * @private
1600  */
1601 function wfMsgReplaceArgs( $message, $args ) {
1602         # Fix windows line-endings
1603         # Some messages are split with explode("\n", $msg)
1604         $message = str_replace( "\r", '', $message );
1605
1606         // Replace arguments
1607         if ( count( $args ) ) {
1608                 if ( is_array( $args[0] ) ) {
1609                         $args = array_values( $args[0] );
1610                 }
1611                 $replacementKeys = array();
1612                 foreach ( $args as $n => $param ) {
1613                         $replacementKeys['$' . ( $n + 1 )] = $param;
1614                 }
1615                 $message = strtr( $message, $replacementKeys );
1616         }
1617
1618         return $message;
1619 }
1620
1621 /**
1622  * Return an HTML-escaped version of a message.
1623  * Parameter replacements, if any, are done *after* the HTML-escaping,
1624  * so parameters may contain HTML (eg links or form controls). Be sure
1625  * to pre-escape them if you really do want plaintext, or just wrap
1626  * the whole thing in htmlspecialchars().
1627  *
1628  * @deprecated since 1.18
1629  *
1630  * @param string $key
1631  * @param string $args,... Parameters
1632  * @return string
1633  */
1634 function wfMsgHtml( $key ) {
1635         wfDeprecated( __METHOD__, '1.21' );
1636
1637         $args = func_get_args();
1638         array_shift( $args );
1639         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1640 }
1641
1642 /**
1643  * Return an HTML version of message
1644  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1645  * so parameters may contain HTML (eg links or form controls). Be sure
1646  * to pre-escape them if you really do want plaintext, or just wrap
1647  * the whole thing in htmlspecialchars().
1648  *
1649  * @deprecated since 1.18
1650  *
1651  * @param string $key
1652  * @param string $args,... Parameters
1653  * @return string
1654  */
1655 function wfMsgWikiHtml( $key ) {
1656         wfDeprecated( __METHOD__, '1.21' );
1657
1658         $args = func_get_args();
1659         array_shift( $args );
1660         return wfMsgReplaceArgs(
1661                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1662                 /* can't be set to false */ true, /* interface */ true )->getText(),
1663                 $args );
1664 }
1665
1666 /**
1667  * Returns message in the requested format
1668  *
1669  * @deprecated since 1.18
1670  *
1671  * @param string $key Key of the message
1672  * @param array $options Processing rules.
1673  *   Can take the following options:
1674  *     parse: parses wikitext to HTML
1675  *     parseinline: parses wikitext to HTML and removes the surrounding
1676  *       p's added by parser or tidy
1677  *     escape: filters message through htmlspecialchars
1678  *     escapenoentities: same, but allows entity references like &#160; through
1679  *     replaceafter: parameters are substituted after parsing or escaping
1680  *     parsemag: transform the message using magic phrases
1681  *     content: fetch message for content language instead of interface
1682  *   Also can accept a single associative argument, of the form 'language' => 'xx':
1683  *     language: Language object or language code to fetch message for
1684  *       (overridden by content).
1685  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1686  *
1687  * @return string
1688  */
1689 function wfMsgExt( $key, $options ) {
1690         wfDeprecated( __METHOD__, '1.21' );
1691
1692         $args = func_get_args();
1693         array_shift( $args );
1694         array_shift( $args );
1695         $options = (array)$options;
1696         $validOptions = array( 'parse', 'parseinline', 'escape', 'escapenoentities', 'replaceafter',
1697                 'parsemag', 'content' );
1698
1699         foreach ( $options as $arrayKey => $option ) {
1700                 if ( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1701                         // An unknown index, neither numeric nor "language"
1702                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1703                 } elseif ( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option, $validOptions ) ) {
1704                         // A numeric index with unknown value
1705                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1706                 }
1707         }
1708
1709         if ( in_array( 'content', $options, true ) ) {
1710                 $forContent = true;
1711                 $langCode = true;
1712                 $langCodeObj = null;
1713         } elseif ( array_key_exists( 'language', $options ) ) {
1714                 $forContent = false;
1715                 $langCode = wfGetLangObj( $options['language'] );
1716                 $langCodeObj = $langCode;
1717         } else {
1718                 $forContent = false;
1719                 $langCode = false;
1720                 $langCodeObj = null;
1721         }
1722
1723         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1724
1725         if ( !in_array( 'replaceafter', $options, true ) ) {
1726                 $string = wfMsgReplaceArgs( $string, $args );
1727         }
1728
1729         $messageCache = MessageCache::singleton();
1730         $parseInline = in_array( 'parseinline', $options, true );
1731         if ( in_array( 'parse', $options, true ) || $parseInline ) {
1732                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1733                 if ( $string instanceof ParserOutput ) {
1734                         $string = $string->getText();
1735                 }
1736
1737                 if ( $parseInline ) {
1738                         $string = Parser::stripOuterParagraph( $string );
1739                 }
1740         } elseif ( in_array( 'parsemag', $options, true ) ) {
1741                 $string = $messageCache->transform( $string,
1742                                 !$forContent, $langCodeObj );
1743         }
1744
1745         if ( in_array( 'escape', $options, true ) ) {
1746                 $string = htmlspecialchars( $string );
1747         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1748                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1749         }
1750
1751         if ( in_array( 'replaceafter', $options, true ) ) {
1752                 $string = wfMsgReplaceArgs( $string, $args );
1753         }
1754
1755         return $string;
1756 }
1757
1758 /**
1759  * Fetch server name for use in error reporting etc.
1760  * Use real server name if available, so we know which machine
1761  * in a server farm generated the current page.
1762  *
1763  * @return string
1764  */
1765 function wfHostname() {
1766         static $host;
1767         if ( is_null( $host ) ) {
1768
1769                 # Hostname overriding
1770                 global $wgOverrideHostname;
1771                 if ( $wgOverrideHostname !== false ) {
1772                         # Set static and skip any detection
1773                         $host = $wgOverrideHostname;
1774                         return $host;
1775                 }
1776
1777                 if ( function_exists( 'posix_uname' ) ) {
1778                         // This function not present on Windows
1779                         $uname = posix_uname();
1780                 } else {
1781                         $uname = false;
1782                 }
1783                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1784                         $host = $uname['nodename'];
1785                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1786                         # Windows computer name
1787                         $host = getenv( 'COMPUTERNAME' );
1788                 } else {
1789                         # This may be a virtual server.
1790                         $host = $_SERVER['SERVER_NAME'];
1791                 }
1792         }
1793         return $host;
1794 }
1795
1796 /**
1797  * Returns a script tag that stores the amount of time it took MediaWiki to
1798  * handle the request in milliseconds as 'wgBackendResponseTime'.
1799  *
1800  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1801  * hostname of the server handling the request.
1802  *
1803  * @return string
1804  */
1805 function wfReportTime() {
1806         global $wgRequestTime, $wgShowHostnames;
1807
1808         $responseTime = round( ( microtime( true ) - $wgRequestTime ) * 1000 );
1809         $reportVars = array( 'wgBackendResponseTime' => $responseTime );
1810         if ( $wgShowHostnames ) {
1811                 $reportVars['wgHostname'] = wfHostname();
1812         }
1813         return Skin::makeVariablesScript( $reportVars );
1814 }
1815
1816 /**
1817  * Safety wrapper for debug_backtrace().
1818  *
1819  * Will return an empty array if debug_backtrace is disabled, otherwise
1820  * the output from debug_backtrace() (trimmed).
1821  *
1822  * @param int $limit This parameter can be used to limit the number of stack frames returned
1823  *
1824  * @return array Array of backtrace information
1825  */
1826 function wfDebugBacktrace( $limit = 0 ) {
1827         static $disabled = null;
1828
1829         if ( is_null( $disabled ) ) {
1830                 $disabled = !function_exists( 'debug_backtrace' );
1831                 if ( $disabled ) {
1832                         wfDebug( "debug_backtrace() is disabled\n" );
1833                 }
1834         }
1835         if ( $disabled ) {
1836                 return array();
1837         }
1838
1839         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1840                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1841         } else {
1842                 return array_slice( debug_backtrace(), 1 );
1843         }
1844 }
1845
1846 /**
1847  * Get a debug backtrace as a string
1848  *
1849  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1850  *   Defaults to $wgCommandLineMode if unset.
1851  * @return string
1852  * @since 1.25 Supports $raw parameter.
1853  */
1854 function wfBacktrace( $raw = null ) {
1855         global $wgCommandLineMode;
1856
1857         if ( $raw === null ) {
1858                 $raw = $wgCommandLineMode;
1859         }
1860
1861         if ( $raw ) {
1862                 $frameFormat = "%s line %s calls %s()\n";
1863                 $traceFormat = "%s";
1864         } else {
1865                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1866                 $traceFormat = "<ul>\n%s</ul>\n";
1867         }
1868
1869         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1870                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1871                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1872                 $call = $frame['function'];
1873                 if ( !empty( $frame['class'] ) ) {
1874                         $call = $frame['class'] . $frame['type'] . $call;
1875                 }
1876                 return sprintf( $frameFormat, $file, $line, $call );
1877         }, wfDebugBacktrace() );
1878
1879         return sprintf( $traceFormat, implode( '', $frames ) );
1880 }
1881
1882 /**
1883  * Get the name of the function which called this function
1884  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1885  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1886  * wfGetCaller( 3 ) is the parent of that.
1887  *
1888  * @param int $level
1889  * @return string
1890  */
1891 function wfGetCaller( $level = 2 ) {
1892         $backtrace = wfDebugBacktrace( $level + 1 );
1893         if ( isset( $backtrace[$level] ) ) {
1894                 return wfFormatStackFrame( $backtrace[$level] );
1895         } else {
1896                 return 'unknown';
1897         }
1898 }
1899
1900 /**
1901  * Return a string consisting of callers in the stack. Useful sometimes
1902  * for profiling specific points.
1903  *
1904  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1905  * @return string
1906  */
1907 function wfGetAllCallers( $limit = 3 ) {
1908         $trace = array_reverse( wfDebugBacktrace() );
1909         if ( !$limit || $limit > count( $trace ) - 1 ) {
1910                 $limit = count( $trace ) - 1;
1911         }
1912         $trace = array_slice( $trace, -$limit - 1, $limit );
1913         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1914 }
1915
1916 /**
1917  * Return a string representation of frame
1918  *
1919  * @param array $frame
1920  * @return string
1921  */
1922 function wfFormatStackFrame( $frame ) {
1923         if ( !isset( $frame['function'] ) ) {
1924                 return 'NO_FUNCTION_GIVEN';
1925         }
1926         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1927                 $frame['class'] . $frame['type'] . $frame['function'] :
1928                 $frame['function'];
1929 }
1930
1931 /* Some generic result counters, pulled out of SearchEngine */
1932
1933 /**
1934  * @todo document
1935  *
1936  * @param int $offset
1937  * @param int $limit
1938  * @return string
1939  */
1940 function wfShowingResults( $offset, $limit ) {
1941         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1942 }
1943
1944 /**
1945  * @todo document
1946  * @todo FIXME: We may want to blacklist some broken browsers
1947  *
1948  * @param bool $force
1949  * @return bool Whereas client accept gzip compression
1950  */
1951 function wfClientAcceptsGzip( $force = false ) {
1952         static $result = null;
1953         if ( $result === null || $force ) {
1954                 $result = false;
1955                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1956                         # @todo FIXME: We may want to blacklist some broken browsers
1957                         $m = array();
1958                         if ( preg_match(
1959                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1960                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1961                                         $m
1962                                 )
1963                         ) {
1964                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1965                                         $result = false;
1966                                         return $result;
1967                                 }
1968                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1969                                 $result = true;
1970                         }
1971                 }
1972         }
1973         return $result;
1974 }
1975
1976 /**
1977  * Escapes the given text so that it may be output using addWikiText()
1978  * without any linking, formatting, etc. making its way through. This
1979  * is achieved by substituting certain characters with HTML entities.
1980  * As required by the callers, "<nowiki>" is not used.
1981  *
1982  * @param string $text Text to be escaped
1983  * @return string
1984  */
1985 function wfEscapeWikiText( $text ) {
1986         static $repl = null, $repl2 = null;
1987         if ( $repl === null ) {
1988                 $repl = array(
1989                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1990                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1991                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1992                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1993                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1994                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1995                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1996                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1997                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1998                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1999                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
2000                         '__' => '_&#95;', '://' => '&#58;//',
2001                 );
2002
2003                 // We have to catch everything "\s" matches in PCRE
2004                 foreach ( array( 'ISBN', 'RFC', 'PMID' ) as $magic ) {
2005                         $repl["$magic "] = "$magic&#32;";
2006                         $repl["$magic\t"] = "$magic&#9;";
2007                         $repl["$magic\r"] = "$magic&#13;";
2008                         $repl["$magic\n"] = "$magic&#10;";
2009                         $repl["$magic\f"] = "$magic&#12;";
2010                 }
2011
2012                 // And handle protocols that don't use "://"
2013                 global $wgUrlProtocols;
2014                 $repl2 = array();
2015                 foreach ( $wgUrlProtocols as $prot ) {
2016                         if ( substr( $prot, -1 ) === ':' ) {
2017                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
2018                         }
2019                 }
2020                 $repl2 = $repl2 ? '/\b(' . join( '|', $repl2 ) . '):/i' : '/^(?!)/';
2021         }
2022         $text = substr( strtr( "\n$text", $repl ), 1 );
2023         $text = preg_replace( $repl2, '$1&#58;', $text );
2024         return $text;
2025 }
2026
2027 /**
2028  * Sets dest to source and returns the original value of dest
2029  * If source is NULL, it just returns the value, it doesn't set the variable
2030  * If force is true, it will set the value even if source is NULL
2031  *
2032  * @param mixed $dest
2033  * @param mixed $source
2034  * @param bool $force
2035  * @return mixed
2036  */
2037 function wfSetVar( &$dest, $source, $force = false ) {
2038         $temp = $dest;
2039         if ( !is_null( $source ) || $force ) {
2040                 $dest = $source;
2041         }
2042         return $temp;
2043 }
2044
2045 /**
2046  * As for wfSetVar except setting a bit
2047  *
2048  * @param int $dest
2049  * @param int $bit
2050  * @param bool $state
2051  *
2052  * @return bool
2053  */
2054 function wfSetBit( &$dest, $bit, $state = true ) {
2055         $temp = (bool)( $dest & $bit );
2056         if ( !is_null( $state ) ) {
2057                 if ( $state ) {
2058                         $dest |= $bit;
2059                 } else {
2060                         $dest &= ~$bit;
2061                 }
2062         }
2063         return $temp;
2064 }
2065
2066 /**
2067  * A wrapper around the PHP function var_export().
2068  * Either print it or add it to the regular output ($wgOut).
2069  *
2070  * @param mixed $var A PHP variable to dump.
2071  */
2072 function wfVarDump( $var ) {
2073         global $wgOut;
2074         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2075         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2076                 print $s;
2077         } else {
2078                 $wgOut->addHTML( $s );
2079         }
2080 }
2081
2082 /**
2083  * Provide a simple HTTP error.
2084  *
2085  * @param int|string $code
2086  * @param string $label
2087  * @param string $desc
2088  */
2089 function wfHttpError( $code, $label, $desc ) {
2090         global $wgOut;
2091         HttpStatus::header( $code );
2092         if ( $wgOut ) {
2093                 $wgOut->disable();
2094                 $wgOut->sendCacheControl();
2095         }
2096
2097         header( 'Content-type: text/html; charset=utf-8' );
2098         print '<!DOCTYPE html>' .
2099                 '<html><head><title>' .
2100                 htmlspecialchars( $label ) .
2101                 '</title></head><body><h1>' .
2102                 htmlspecialchars( $label ) .
2103                 '</h1><p>' .
2104                 nl2br( htmlspecialchars( $desc ) ) .
2105                 "</p></body></html>\n";
2106 }
2107
2108 /**
2109  * Clear away any user-level output buffers, discarding contents.
2110  *
2111  * Suitable for 'starting afresh', for instance when streaming
2112  * relatively large amounts of data without buffering, or wanting to
2113  * output image files without ob_gzhandler's compression.
2114  *
2115  * The optional $resetGzipEncoding parameter controls suppression of
2116  * the Content-Encoding header sent by ob_gzhandler; by default it
2117  * is left. See comments for wfClearOutputBuffers() for why it would
2118  * be used.
2119  *
2120  * Note that some PHP configuration options may add output buffer
2121  * layers which cannot be removed; these are left in place.
2122  *
2123  * @param bool $resetGzipEncoding
2124  */
2125 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2126         if ( $resetGzipEncoding ) {
2127                 // Suppress Content-Encoding and Content-Length
2128                 // headers from 1.10+s wfOutputHandler
2129                 global $wgDisableOutputCompression;
2130                 $wgDisableOutputCompression = true;
2131         }
2132         while ( $status = ob_get_status() ) {
2133                 if ( isset( $status['flags'] ) ) {
2134                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
2135                         $deleteable = ( $status['flags'] & $flags ) === $flags;
2136                 } elseif ( isset( $status['del'] ) ) {
2137                         $deleteable = $status['del'];
2138                 } else {
2139                         // Guess that any PHP-internal setting can't be removed.
2140                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
2141                 }
2142                 if ( !$deleteable ) {
2143                         // Give up, and hope the result doesn't break
2144                         // output behavior.
2145                         break;
2146                 }
2147                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
2148                         // Unit testing barrier to prevent this function from breaking PHPUnit.
2149                         break;
2150                 }
2151                 if ( !ob_end_clean() ) {
2152                         // Could not remove output buffer handler; abort now
2153                         // to avoid getting in some kind of infinite loop.
2154                         break;
2155                 }
2156                 if ( $resetGzipEncoding ) {
2157                         if ( $status['name'] == 'ob_gzhandler' ) {
2158                                 // Reset the 'Content-Encoding' field set by this handler
2159                                 // so we can start fresh.
2160                                 header_remove( 'Content-Encoding' );
2161                                 break;
2162                         }
2163                 }
2164         }
2165 }
2166
2167 /**
2168  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2169  *
2170  * Clear away output buffers, but keep the Content-Encoding header
2171  * produced by ob_gzhandler, if any.
2172  *
2173  * This should be used for HTTP 304 responses, where you need to
2174  * preserve the Content-Encoding header of the real result, but
2175  * also need to suppress the output of ob_gzhandler to keep to spec
2176  * and avoid breaking Firefox in rare cases where the headers and
2177  * body are broken over two packets.
2178  */
2179 function wfClearOutputBuffers() {
2180         wfResetOutputBuffers( false );
2181 }
2182
2183 /**
2184  * Converts an Accept-* header into an array mapping string values to quality
2185  * factors
2186  *
2187  * @param string $accept
2188  * @param string $def Default
2189  * @return float[] Associative array of string => float pairs
2190  */
2191 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2192         # No arg means accept anything (per HTTP spec)
2193         if ( !$accept ) {
2194                 return array( $def => 1.0 );
2195         }
2196
2197         $prefs = array();
2198
2199         $parts = explode( ',', $accept );
2200
2201         foreach ( $parts as $part ) {
2202                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2203                 $values = explode( ';', trim( $part ) );
2204                 $match = array();
2205                 if ( count( $values ) == 1 ) {
2206                         $prefs[$values[0]] = 1.0;
2207                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2208                         $prefs[$values[0]] = floatval( $match[1] );
2209                 }
2210         }
2211
2212         return $prefs;
2213 }
2214
2215 /**
2216  * Checks if a given MIME type matches any of the keys in the given
2217  * array. Basic wildcards are accepted in the array keys.
2218  *
2219  * Returns the matching MIME type (or wildcard) if a match, otherwise
2220  * NULL if no match.
2221  *
2222  * @param string $type
2223  * @param array $avail
2224  * @return string
2225  * @private
2226  */
2227 function mimeTypeMatch( $type, $avail ) {
2228         if ( array_key_exists( $type, $avail ) ) {
2229                 return $type;
2230         } else {
2231                 $parts = explode( '/', $type );
2232                 if ( array_key_exists( $parts[0] . '/*', $avail ) ) {
2233                         return $parts[0] . '/*';
2234                 } elseif ( array_key_exists( '*/*', $avail ) ) {
2235                         return '*/*';
2236                 } else {
2237                         return null;
2238                 }
2239         }
2240 }
2241
2242 /**
2243  * Returns the 'best' match between a client's requested internet media types
2244  * and the server's list of available types. Each list should be an associative
2245  * array of type to preference (preference is a float between 0.0 and 1.0).
2246  * Wildcards in the types are acceptable.
2247  *
2248  * @param array $cprefs Client's acceptable type list
2249  * @param array $sprefs Server's offered types
2250  * @return string
2251  *
2252  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2253  * XXX: generalize to negotiate other stuff
2254  */
2255 function wfNegotiateType( $cprefs, $sprefs ) {
2256         $combine = array();
2257
2258         foreach ( array_keys( $sprefs ) as $type ) {
2259                 $parts = explode( '/', $type );
2260                 if ( $parts[1] != '*' ) {
2261                         $ckey = mimeTypeMatch( $type, $cprefs );
2262                         if ( $ckey ) {
2263                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2264                         }
2265                 }
2266         }
2267
2268         foreach ( array_keys( $cprefs ) as $type ) {
2269                 $parts = explode( '/', $type );
2270                 if ( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2271                         $skey = mimeTypeMatch( $type, $sprefs );
2272                         if ( $skey ) {
2273                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2274                         }
2275                 }
2276         }
2277
2278         $bestq = 0;
2279         $besttype = null;
2280
2281         foreach ( array_keys( $combine ) as $type ) {
2282                 if ( $combine[$type] > $bestq ) {
2283                         $besttype = $type;
2284                         $bestq = $combine[$type];
2285                 }
2286         }
2287
2288         return $besttype;
2289 }
2290
2291 /**
2292  * Reference-counted warning suppression
2293  *
2294  * @deprecated since 1.26, use MediaWiki\suppressWarnings() directly
2295  * @param bool $end
2296  */
2297 function wfSuppressWarnings( $end = false ) {
2298         MediaWiki\suppressWarnings( $end );
2299 }
2300
2301 /**
2302  * @deprecated since 1.26, use MediaWiki\restoreWarnings() directly
2303  * Restore error level to previous value
2304  */
2305 function wfRestoreWarnings() {
2306         MediaWiki\suppressWarnings( true );
2307 }
2308
2309 # Autodetect, convert and provide timestamps of various types
2310
2311 /**
2312  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2313  */
2314 define( 'TS_UNIX', 0 );
2315
2316 /**
2317  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2318  */
2319 define( 'TS_MW', 1 );
2320
2321 /**
2322  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2323  */
2324 define( 'TS_DB', 2 );
2325
2326 /**
2327  * RFC 2822 format, for E-mail and HTTP headers
2328  */
2329 define( 'TS_RFC2822', 3 );
2330
2331 /**
2332  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2333  *
2334  * This is used by Special:Export
2335  */
2336 define( 'TS_ISO_8601', 4 );
2337
2338 /**
2339  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2340  *
2341  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2342  *       DateTime tag and page 36 for the DateTimeOriginal and
2343  *       DateTimeDigitized tags.
2344  */
2345 define( 'TS_EXIF', 5 );
2346
2347 /**
2348  * Oracle format time.
2349  */
2350 define( 'TS_ORACLE', 6 );
2351
2352 /**
2353  * Postgres format time.
2354  */
2355 define( 'TS_POSTGRES', 7 );
2356
2357 /**
2358  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2359  */
2360 define( 'TS_ISO_8601_BASIC', 9 );
2361
2362 /**
2363  * Get a timestamp string in one of various formats
2364  *
2365  * @param mixed $outputtype A timestamp in one of the supported formats, the
2366  *   function will autodetect which format is supplied and act accordingly.
2367  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2368  * @return string|bool String / false The same date in the format specified in $outputtype or false
2369  */
2370 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2371         try {
2372                 $timestamp = new MWTimestamp( $ts );
2373                 return $timestamp->getTimestamp( $outputtype );
2374         } catch ( TimestampException $e ) {
2375                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2376                 return false;
2377         }
2378 }
2379
2380 /**
2381  * Return a formatted timestamp, or null if input is null.
2382  * For dealing with nullable timestamp columns in the database.
2383  *
2384  * @param int $outputtype
2385  * @param string $ts
2386  * @return string
2387  */
2388 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2389         if ( is_null( $ts ) ) {
2390                 return null;
2391         } else {
2392                 return wfTimestamp( $outputtype, $ts );
2393         }
2394 }
2395
2396 /**
2397  * Convenience function; returns MediaWiki timestamp for the present time.
2398  *
2399  * @return string
2400  */
2401 function wfTimestampNow() {
2402         # return NOW
2403         return wfTimestamp( TS_MW, time() );
2404 }
2405
2406 /**
2407  * Check if the operating system is Windows
2408  *
2409  * @return bool True if it's Windows, false otherwise.
2410  */
2411 function wfIsWindows() {
2412         static $isWindows = null;
2413         if ( $isWindows === null ) {
2414                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2415         }
2416         return $isWindows;
2417 }
2418
2419 /**
2420  * Check if we are running under HHVM
2421  *
2422  * @return bool
2423  */
2424 function wfIsHHVM() {
2425         return defined( 'HHVM_VERSION' );
2426 }
2427
2428 /**
2429  * Tries to get the system directory for temporary files. First
2430  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2431  * environment variables are then checked in sequence, and if none are
2432  * set try sys_get_temp_dir().
2433  *
2434  * NOTE: When possible, use instead the tmpfile() function to create
2435  * temporary files to avoid race conditions on file creation, etc.
2436  *
2437  * @return string
2438  */
2439 function wfTempDir() {
2440         global $wgTmpDirectory;
2441
2442         if ( $wgTmpDirectory !== false ) {
2443                 return $wgTmpDirectory;
2444         }
2445
2446         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2447
2448         foreach ( $tmpDir as $tmp ) {
2449                 if ( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2450                         return $tmp;
2451                 }
2452         }
2453         return sys_get_temp_dir();
2454 }
2455
2456 /**
2457  * Make directory, and make all parent directories if they don't exist
2458  *
2459  * @param string $dir Full path to directory to create
2460  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2461  * @param string $caller Optional caller param for debugging.
2462  * @throws MWException
2463  * @return bool
2464  */
2465 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2466         global $wgDirectoryMode;
2467
2468         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2469                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2470         }
2471
2472         if ( !is_null( $caller ) ) {
2473                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2474         }
2475
2476         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2477                 return true;
2478         }
2479
2480         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2481
2482         if ( is_null( $mode ) ) {
2483                 $mode = $wgDirectoryMode;
2484         }
2485
2486         // Turn off the normal warning, we're doing our own below
2487         MediaWiki\suppressWarnings();
2488         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2489         MediaWiki\restoreWarnings();
2490
2491         if ( !$ok ) {
2492                 // directory may have been created on another request since we last checked
2493                 if ( is_dir( $dir ) ) {
2494                         return true;
2495                 }
2496
2497                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2498                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2499         }
2500         return $ok;
2501 }
2502
2503 /**
2504  * Remove a directory and all its content.
2505  * Does not hide error.
2506  * @param string $dir
2507  */
2508 function wfRecursiveRemoveDir( $dir ) {
2509         wfDebug( __FUNCTION__ . "( $dir )\n" );
2510         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2511         if ( is_dir( $dir ) ) {
2512                 $objects = scandir( $dir );
2513                 foreach ( $objects as $object ) {
2514                         if ( $object != "." && $object != ".." ) {
2515                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2516                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2517                                 } else {
2518                                         unlink( $dir . '/' . $object );
2519                                 }
2520                         }
2521                 }
2522                 reset( $objects );
2523                 rmdir( $dir );
2524         }
2525 }
2526
2527 /**
2528  * @param int $nr The number to format
2529  * @param int $acc The number of digits after the decimal point, default 2
2530  * @param bool $round Whether or not to round the value, default true
2531  * @return string
2532  */
2533 function wfPercent( $nr, $acc = 2, $round = true ) {
2534         $ret = sprintf( "%.${acc}f", $nr );
2535         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2536 }
2537
2538 /**
2539  * Safety wrapper around ini_get() for boolean settings.
2540  * The values returned from ini_get() are pre-normalized for settings
2541  * set via php.ini or php_flag/php_admin_flag... but *not*
2542  * for those set via php_value/php_admin_value.
2543  *
2544  * It's fairly common for people to use php_value instead of php_flag,
2545  * which can leave you with an 'off' setting giving a false positive
2546  * for code that just takes the ini_get() return value as a boolean.
2547  *
2548  * To make things extra interesting, setting via php_value accepts
2549  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2550  * Unrecognized values go false... again opposite PHP's own coercion
2551  * from string to bool.
2552  *
2553  * Luckily, 'properly' set settings will always come back as '0' or '1',
2554  * so we only have to worry about them and the 'improper' settings.
2555  *
2556  * I frickin' hate PHP... :P
2557  *
2558  * @param string $setting
2559  * @return bool
2560  */
2561 function wfIniGetBool( $setting ) {
2562         $val = strtolower( ini_get( $setting ) );
2563         // 'on' and 'true' can't have whitespace around them, but '1' can.
2564         return $val == 'on'
2565                 || $val == 'true'
2566                 || $val == 'yes'
2567                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2568 }
2569
2570 /**
2571  * Windows-compatible version of escapeshellarg()
2572  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2573  * function puts single quotes in regardless of OS.
2574  *
2575  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2576  * earlier distro releases of PHP)
2577  *
2578  * @param string ... strings to escape and glue together, or a single array of strings parameter
2579  * @return string
2580  */
2581 function wfEscapeShellArg( /*...*/ ) {
2582         wfInitShellLocale();
2583
2584         $args = func_get_args();
2585         if ( count( $args ) === 1 && is_array( reset( $args ) ) ) {
2586                 // If only one argument has been passed, and that argument is an array,
2587                 // treat it as a list of arguments
2588                 $args = reset( $args );
2589         }
2590
2591         $first = true;
2592         $retVal = '';
2593         foreach ( $args as $arg ) {
2594                 if ( !$first ) {
2595                         $retVal .= ' ';
2596                 } else {
2597                         $first = false;
2598                 }
2599
2600                 if ( wfIsWindows() ) {
2601                         // Escaping for an MSVC-style command line parser and CMD.EXE
2602                         // @codingStandardsIgnoreStart For long URLs
2603                         // Refs:
2604                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2605                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2606                         //  * Bug #13518
2607                         //  * CR r63214
2608                         // Double the backslashes before any double quotes. Escape the double quotes.
2609                         // @codingStandardsIgnoreEnd
2610                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2611                         $arg = '';
2612                         $iteration = 0;
2613                         foreach ( $tokens as $token ) {
2614                                 if ( $iteration % 2 == 1 ) {
2615                                         // Delimiter, a double quote preceded by zero or more slashes
2616                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2617                                 } elseif ( $iteration % 4 == 2 ) {
2618                                         // ^ in $token will be outside quotes, need to be escaped
2619                                         $arg .= str_replace( '^', '^^', $token );
2620                                 } else { // $iteration % 4 == 0
2621                                         // ^ in $token will appear inside double quotes, so leave as is
2622                                         $arg .= $token;
2623                                 }
2624                                 $iteration++;
2625                         }
2626                         // Double the backslashes before the end of the string, because
2627                         // we will soon add a quote
2628                         $m = array();
2629                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2630                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2631                         }
2632
2633                         // Add surrounding quotes
2634                         $retVal .= '"' . $arg . '"';
2635                 } else {
2636                         $retVal .= escapeshellarg( $arg );
2637                 }
2638         }
2639         return $retVal;
2640 }
2641
2642 /**
2643  * Check if wfShellExec() is effectively disabled via php.ini config
2644  *
2645  * @return bool|string False or one of (safemode,disabled)
2646  * @since 1.22
2647  */
2648 function wfShellExecDisabled() {
2649         static $disabled = null;
2650         if ( is_null( $disabled ) ) {
2651                 if ( wfIniGetBool( 'safe_mode' ) ) {
2652                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2653                         $disabled = 'safemode';
2654                 } elseif ( !function_exists( 'proc_open' ) ) {
2655                         wfDebug( "proc_open() is disabled\n" );
2656                         $disabled = 'disabled';
2657                 } else {
2658                         $disabled = false;
2659                 }
2660         }
2661         return $disabled;
2662 }
2663
2664 /**
2665  * Execute a shell command, with time and memory limits mirrored from the PHP
2666  * configuration if supported.
2667  *
2668  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2669  *   or an array of unescaped arguments, in which case each value will be escaped
2670  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2671  * @param null|mixed &$retval Optional, will receive the program's exit code.
2672  *   (non-zero is usually failure). If there is an error from
2673  *   read, select, or proc_open(), this will be set to -1.
2674  * @param array $environ Optional environment variables which should be
2675  *   added to the executed command environment.
2676  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2677  *   this overwrites the global wgMaxShell* limits.
2678  * @param array $options Array of options:
2679  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2680  *     including errors from limit.sh
2681  *   - profileMethod: By default this function will profile based on the calling
2682  *     method. Set this to a string for an alternative method to profile from
2683  *
2684  * @return string Collected stdout as a string
2685  */
2686 function wfShellExec( $cmd, &$retval = null, $environ = array(),
2687         $limits = array(), $options = array()
2688 ) {
2689         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2690                 $wgMaxShellWallClockTime, $wgShellCgroup;
2691
2692         $disabled = wfShellExecDisabled();
2693         if ( $disabled ) {
2694                 $retval = 1;
2695                 return $disabled == 'safemode' ?
2696                         'Unable to run external programs in safe mode.' :
2697                         'Unable to run external programs, proc_open() is disabled.';
2698         }
2699
2700         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2701         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2702
2703         wfInitShellLocale();
2704
2705         $envcmd = '';
2706         foreach ( $environ as $k => $v ) {
2707                 if ( wfIsWindows() ) {
2708                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2709                          * appear in the environment variable, so we must use carat escaping as documented in
2710                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2711                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2712                          * are listed there but doesn't appear to need it.
2713                          */
2714                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2715                 } else {
2716                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2717                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2718                          */
2719                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2720                 }
2721         }
2722         if ( is_array( $cmd ) ) {
2723                 $cmd = wfEscapeShellArg( $cmd );
2724         }
2725
2726         $cmd = $envcmd . $cmd;
2727
2728         $useLogPipe = false;
2729         if ( is_executable( '/bin/bash' ) ) {
2730                 $time = intval( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2731                 if ( isset( $limits['walltime'] ) ) {
2732                         $wallTime = intval( $limits['walltime'] );
2733                 } elseif ( isset( $limits['time'] ) ) {
2734                         $wallTime = $time;
2735                 } else {
2736                         $wallTime = intval( $wgMaxShellWallClockTime );
2737                 }
2738                 $mem = intval( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2739                 $filesize = intval( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2740
2741                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2742                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2743                                 escapeshellarg( $cmd ) . ' ' .
2744                                 escapeshellarg(
2745                                         "MW_INCLUDE_STDERR=" . ( $includeStderr ? '1' : '' ) . ';' .
2746                                         "MW_CPU_LIMIT=$time; " .
2747                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2748                                         "MW_MEM_LIMIT=$mem; " .
2749                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2750                                         "MW_WALL_CLOCK_LIMIT=$wallTime; " .
2751                                         "MW_USE_LOG_PIPE=yes"
2752                                 );
2753                         $useLogPipe = true;
2754                 } elseif ( $includeStderr ) {
2755                         $cmd .= ' 2>&1';
2756                 }
2757         } elseif ( $includeStderr ) {
2758                 $cmd .= ' 2>&1';
2759         }
2760         wfDebug( "wfShellExec: $cmd\n" );
2761
2762         $desc = array(
2763                 0 => array( 'file', 'php://stdin', 'r' ),
2764                 1 => array( 'pipe', 'w' ),
2765                 2 => array( 'file', 'php://stderr', 'w' ) );
2766         if ( $useLogPipe ) {
2767                 $desc[3] = array( 'pipe', 'w' );
2768         }
2769         $pipes = null;
2770         $scoped = Profiler::instance()->scopedProfileIn( __FUNCTION__ . '-' . $profileMethod );
2771         $proc = proc_open( $cmd, $desc, $pipes );
2772         if ( !$proc ) {
2773                 wfDebugLog( 'exec', "proc_open() failed: $cmd" );
2774                 $retval = -1;
2775                 return '';
2776         }
2777         $outBuffer = $logBuffer = '';
2778         $emptyArray = array();
2779         $status = false;
2780         $logMsg = false;
2781
2782         /* According to the documentation, it is possible for stream_select()
2783          * to fail due to EINTR. I haven't managed to induce this in testing
2784          * despite sending various signals. If it did happen, the error
2785          * message would take the form:
2786          *
2787          * stream_select(): unable to select [4]: Interrupted system call (max_fd=5)
2788          *
2789          * where [4] is the value of the macro EINTR and "Interrupted system
2790          * call" is string which according to the Linux manual is "possibly"
2791          * localised according to LC_MESSAGES.
2792          */
2793         $eintr = defined( 'SOCKET_EINTR' ) ? SOCKET_EINTR : 4;
2794         $eintrMessage = "stream_select(): unable to select [$eintr]";
2795
2796         // Build a table mapping resource IDs to pipe FDs to work around a
2797         // PHP 5.3 issue in which stream_select() does not preserve array keys
2798         // <https://bugs.php.net/bug.php?id=53427>.
2799         $fds = array();
2800         foreach ( $pipes as $fd => $pipe ) {
2801                 $fds[(int)$pipe] = $fd;
2802         }
2803
2804         $running = true;
2805         $timeout = null;
2806         $numReadyPipes = 0;
2807
2808         while ( $running === true || $numReadyPipes !== 0 ) {
2809                 if ( $running ) {
2810                         $status = proc_get_status( $proc );
2811                         // If the process has terminated, switch to nonblocking selects
2812                         // for getting any data still waiting to be read.
2813                         if ( !$status['running'] ) {
2814                                 $running = false;
2815                                 $timeout = 0;
2816                         }
2817                 }
2818
2819                 $readyPipes = $pipes;
2820
2821                 // Clear last error
2822                 // @codingStandardsIgnoreStart Generic.PHP.NoSilencedErrors.Discouraged
2823                 @trigger_error( '' );
2824                 $numReadyPipes = @stream_select( $readyPipes, $emptyArray, $emptyArray, $timeout );
2825                 if ( $numReadyPipes === false ) {
2826                         // @codingStandardsIgnoreEnd
2827                         $error = error_get_last();
2828                         if ( strncmp( $error['message'], $eintrMessage, strlen( $eintrMessage ) ) == 0 ) {
2829                                 continue;
2830                         } else {
2831                                 trigger_error( $error['message'], E_USER_WARNING );
2832                                 $logMsg = $error['message'];
2833                                 break;
2834                         }
2835                 }
2836                 foreach ( $readyPipes as $pipe ) {
2837                         $block = fread( $pipe, 65536 );
2838                         $fd = $fds[(int)$pipe];
2839                         if ( $block === '' ) {
2840                                 // End of file
2841                                 fclose( $pipes[$fd] );
2842                                 unset( $pipes[$fd] );
2843                                 if ( !$pipes ) {
2844                                         break 2;
2845                                 }
2846                         } elseif ( $block === false ) {
2847                                 // Read error
2848                                 $logMsg = "Error reading from pipe";
2849                                 break 2;
2850                         } elseif ( $fd == 1 ) {
2851                                 // From stdout
2852                                 $outBuffer .= $block;
2853                         } elseif ( $fd == 3 ) {
2854                                 // From log FD
2855                                 $logBuffer .= $block;
2856                                 if ( strpos( $block, "\n" ) !== false ) {
2857                                         $lines = explode( "\n", $logBuffer );
2858                                         $logBuffer = array_pop( $lines );
2859                                         foreach ( $lines as $line ) {
2860                                                 wfDebugLog( 'exec', $line );
2861                                         }
2862                                 }
2863                         }
2864                 }
2865         }
2866
2867         foreach ( $pipes as $pipe ) {
2868                 fclose( $pipe );
2869         }
2870
2871         // Use the status previously collected if possible, since proc_get_status()
2872         // just calls waitpid() which will not return anything useful the second time.
2873         if ( $running ) {
2874                 $status = proc_get_status( $proc );
2875         }
2876
2877         if ( $logMsg !== false ) {
2878                 // Read/select error
2879                 $retval = -1;
2880                 proc_close( $proc );
2881         } elseif ( $status['signaled'] ) {
2882                 $logMsg = "Exited with signal {$status['termsig']}";
2883                 $retval = 128 + $status['termsig'];
2884                 proc_close( $proc );
2885         } else {
2886                 if ( $status['running'] ) {
2887                         $retval = proc_close( $proc );
2888                 } else {
2889                         $retval = $status['exitcode'];
2890                         proc_close( $proc );
2891                 }
2892                 if ( $retval == 127 ) {
2893                         $logMsg = "Possibly missing executable file";
2894                 } elseif ( $retval >= 129 && $retval <= 192 ) {
2895                         $logMsg = "Probably exited with signal " . ( $retval - 128 );
2896                 }
2897         }
2898
2899         if ( $logMsg !== false ) {
2900                 wfDebugLog( 'exec', "$logMsg: $cmd" );
2901         }
2902
2903         return $outBuffer;
2904 }
2905
2906 /**
2907  * Execute a shell command, returning both stdout and stderr. Convenience
2908  * function, as all the arguments to wfShellExec can become unwieldy.
2909  *
2910  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2911  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2912  *   or an array of unescaped arguments, in which case each value will be escaped
2913  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2914  * @param null|mixed &$retval Optional, will receive the program's exit code.
2915  *   (non-zero is usually failure)
2916  * @param array $environ Optional environment variables which should be
2917  *   added to the executed command environment.
2918  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2919  *   this overwrites the global wgMaxShell* limits.
2920  * @return string Collected stdout and stderr as a string
2921  */
2922 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2923         return wfShellExec( $cmd, $retval, $environ, $limits,
2924                 array( 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ) );
2925 }
2926
2927 /**
2928  * Workaround for http://bugs.php.net/bug.php?id=45132
2929  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2930  */
2931 function wfInitShellLocale() {
2932         static $done = false;
2933         if ( $done ) {
2934                 return;
2935         }
2936         $done = true;
2937         global $wgShellLocale;
2938         if ( !wfIniGetBool( 'safe_mode' ) ) {
2939                 putenv( "LC_CTYPE=$wgShellLocale" );
2940                 setlocale( LC_CTYPE, $wgShellLocale );
2941         }
2942 }
2943
2944 /**
2945  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2946  * Note that $parameters should be a flat array and an option with an argument
2947  * should consist of two consecutive items in the array (do not use "--option value").
2948  *
2949  * @param string $script MediaWiki cli script path
2950  * @param array $parameters Arguments and options to the script
2951  * @param array $options Associative array of options:
2952  *              'php': The path to the php executable
2953  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2954  * @return string
2955  */
2956 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2957         global $wgPhpCli;
2958         // Give site config file a chance to run the script in a wrapper.
2959         // The caller may likely want to call wfBasename() on $script.
2960         Hooks::run( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2961         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2962         if ( isset( $options['wrapper'] ) ) {
2963                 $cmd[] = $options['wrapper'];
2964         }
2965         $cmd[] = $script;
2966         // Escape each parameter for shell
2967         return wfEscapeShellArg( array_merge( $cmd, $parameters ) );
2968 }
2969
2970 /**
2971  * wfMerge attempts to merge differences between three texts.
2972  * Returns true for a clean merge and false for failure or a conflict.
2973  *
2974  * @param string $old
2975  * @param string $mine
2976  * @param string $yours
2977  * @param string $result
2978  * @return bool
2979  */
2980 function wfMerge( $old, $mine, $yours, &$result ) {
2981         global $wgDiff3;
2982
2983         # This check may also protect against code injection in
2984         # case of broken installations.
2985         MediaWiki\suppressWarnings();
2986         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2987         MediaWiki\restoreWarnings();
2988
2989         if ( !$haveDiff3 ) {
2990                 wfDebug( "diff3 not found\n" );
2991                 return false;
2992         }
2993
2994         # Make temporary files
2995         $td = wfTempDir();
2996         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2997         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2998         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2999
3000         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
3001         #       a newline character. To avoid this, we normalize the trailing whitespace before
3002         #       creating the diff.
3003
3004         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
3005         fclose( $oldtextFile );
3006         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
3007         fclose( $mytextFile );
3008         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
3009         fclose( $yourtextFile );
3010
3011         # Check for a conflict
3012         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '--overlap-only', $mytextName,
3013                 $oldtextName, $yourtextName );
3014         $handle = popen( $cmd, 'r' );
3015
3016         if ( fgets( $handle, 1024 ) ) {
3017                 $conflict = true;
3018         } else {
3019                 $conflict = false;
3020         }
3021         pclose( $handle );
3022
3023         # Merge differences
3024         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '-e', '--merge', $mytextName,
3025                 $oldtextName, $yourtextName );
3026         $handle = popen( $cmd, 'r' );
3027         $result = '';
3028         do {
3029                 $data = fread( $handle, 8192 );
3030                 if ( strlen( $data ) == 0 ) {
3031                         break;
3032                 }
3033                 $result .= $data;
3034         } while ( true );
3035         pclose( $handle );
3036         unlink( $mytextName );
3037         unlink( $oldtextName );
3038         unlink( $yourtextName );
3039
3040         if ( $result === '' && $old !== '' && !$conflict ) {
3041                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3042                 $conflict = true;
3043         }
3044         return !$conflict;
3045 }
3046
3047 /**
3048  * Returns unified plain-text diff of two texts.
3049  * "Useful" for machine processing of diffs.
3050  *
3051  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
3052  *
3053  * @param string $before The text before the changes.
3054  * @param string $after The text after the changes.
3055  * @param string $params Command-line options for the diff command.
3056  * @return string Unified diff of $before and $after
3057  */
3058 function wfDiff( $before, $after, $params = '-u' ) {
3059         if ( $before == $after ) {
3060                 return '';
3061         }
3062
3063         global $wgDiff;
3064         MediaWiki\suppressWarnings();
3065         $haveDiff = $wgDiff && file_exists( $wgDiff );
3066         MediaWiki\restoreWarnings();
3067
3068         # This check may also protect against code injection in
3069         # case of broken installations.
3070         if ( !$haveDiff ) {
3071                 wfDebug( "diff executable not found\n" );
3072                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3073                 $format = new UnifiedDiffFormatter();
3074                 return $format->format( $diffs );
3075         }
3076
3077         # Make temporary files
3078         $td = wfTempDir();
3079         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3080         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3081
3082         fwrite( $oldtextFile, $before );
3083         fclose( $oldtextFile );
3084         fwrite( $newtextFile, $after );
3085         fclose( $newtextFile );
3086
3087         // Get the diff of the two files
3088         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3089
3090         $h = popen( $cmd, 'r' );
3091         if ( !$h ) {
3092                 unlink( $oldtextName );
3093                 unlink( $newtextName );
3094                 throw new Exception( __METHOD__ . '(): popen() failed' );
3095         }
3096
3097         $diff = '';
3098
3099         do {
3100                 $data = fread( $h, 8192 );
3101                 if ( strlen( $data ) == 0 ) {
3102                         break;
3103                 }
3104                 $diff .= $data;
3105         } while ( true );
3106
3107         // Clean up
3108         pclose( $h );
3109         unlink( $oldtextName );
3110         unlink( $newtextName );
3111
3112         // Kill the --- and +++ lines. They're not useful.
3113         $diff_lines = explode( "\n", $diff );
3114         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
3115                 unset( $diff_lines[0] );
3116         }
3117         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
3118                 unset( $diff_lines[1] );
3119         }
3120
3121         $diff = implode( "\n", $diff_lines );
3122
3123         return $diff;
3124 }
3125
3126 /**
3127  * This function works like "use VERSION" in Perl, the program will die with a
3128  * backtrace if the current version of PHP is less than the version provided
3129  *
3130  * This is useful for extensions which due to their nature are not kept in sync
3131  * with releases, and might depend on other versions of PHP than the main code
3132  *
3133  * Note: PHP might die due to parsing errors in some cases before it ever
3134  *       manages to call this function, such is life
3135  *
3136  * @see perldoc -f use
3137  *
3138  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3139  * @throws MWException
3140  */
3141 function wfUsePHP( $req_ver ) {
3142         $php_ver = PHP_VERSION;
3143
3144         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3145                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3146         }
3147 }
3148
3149 /**
3150  * This function works like "use VERSION" in Perl except it checks the version
3151  * of MediaWiki, the program will die with a backtrace if the current version
3152  * of MediaWiki is less than the version provided.
3153  *
3154  * This is useful for extensions which due to their nature are not kept in sync
3155  * with releases
3156  *
3157  * Note: Due to the behavior of PHP's version_compare() which is used in this
3158  * function, if you want to allow the 'wmf' development versions add a 'c' (or
3159  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
3160  * targeted version number. For example if you wanted to allow any variation
3161  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
3162  * not result in the same comparison due to the internal logic of
3163  * version_compare().
3164  *
3165  * @see perldoc -f use
3166  *
3167  * @deprecated since 1.26, use the "requires' property of extension.json
3168  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3169  * @throws MWException
3170  */
3171 function wfUseMW( $req_ver ) {
3172         global $wgVersion;
3173
3174         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3175                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3176         }
3177 }
3178
3179 /**
3180  * Return the final portion of a pathname.
3181  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3182  * http://bugs.php.net/bug.php?id=33898
3183  *
3184  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3185  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3186  *
3187  * @param string $path
3188  * @param string $suffix String to remove if present
3189  * @return string
3190  */
3191 function wfBaseName( $path, $suffix = '' ) {
3192         if ( $suffix == '' ) {
3193                 $encSuffix = '';
3194         } else {
3195                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
3196         }
3197
3198         $matches = array();
3199         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3200                 return $matches[1];
3201         } else {
3202                 return '';
3203         }
3204 }
3205
3206 /**
3207  * Generate a relative path name to the given file.
3208  * May explode on non-matching case-insensitive paths,
3209  * funky symlinks, etc.
3210  *
3211  * @param string $path Absolute destination path including target filename
3212  * @param string $from Absolute source path, directory only
3213  * @return string
3214  */
3215 function wfRelativePath( $path, $from ) {
3216         // Normalize mixed input on Windows...
3217         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3218         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3219
3220         // Trim trailing slashes -- fix for drive root
3221         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3222         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3223
3224         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3225         $against = explode( DIRECTORY_SEPARATOR, $from );
3226
3227         if ( $pieces[0] !== $against[0] ) {
3228                 // Non-matching Windows drive letters?
3229                 // Return a full path.
3230                 return $path;
3231         }
3232
3233         // Trim off common prefix
3234         while ( count( $pieces ) && count( $against )
3235                 && $pieces[0] == $against[0] ) {
3236                 array_shift( $pieces );
3237                 array_shift( $against );
3238         }
3239
3240         // relative dots to bump us to the parent
3241         while ( count( $against ) ) {
3242                 array_unshift( $pieces, '..' );
3243                 array_shift( $against );
3244         }
3245
3246         array_push( $pieces, wfBaseName( $path ) );
3247
3248         return implode( DIRECTORY_SEPARATOR, $pieces );
3249 }
3250
3251 /**
3252  * Convert an arbitrarily-long digit string from one numeric base
3253  * to another, optionally zero-padding to a minimum column width.
3254  *
3255  * Supports base 2 through 36; digit values 10-36 are represented
3256  * as lowercase letters a-z. Input is case-insensitive.
3257  *
3258  * @deprecated 1.27 Use Wikimedia\base_convert() directly
3259  *
3260  * @param string $input Input number
3261  * @param int $sourceBase Base of the input number
3262  * @param int $destBase Desired base of the output
3263  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3264  * @param bool $lowercase Whether to output in lowercase or uppercase
3265  * @param string $engine Either "gmp", "bcmath", or "php"
3266  * @return string|bool The output number as a string, or false on error
3267  */
3268 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1,
3269         $lowercase = true, $engine = 'auto'
3270 ) {
3271         return Wikimedia\base_convert( $input, $sourceBase, $destBase, $pad, $lowercase, $engine );
3272 }
3273
3274 /**
3275  * Check if there is sufficient entropy in php's built-in session generation
3276  *
3277  * @return bool True = there is sufficient entropy
3278  */
3279 function wfCheckEntropy() {
3280         return (
3281                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3282                         || ini_get( 'session.entropy_file' )
3283                 )
3284                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3285 }
3286
3287 /**
3288  * Override session_id before session startup if php's built-in
3289  * session generation code is not secure.
3290  */
3291 function wfFixSessionID() {
3292         // If the cookie or session id is already set we already have a session and should abort
3293         if ( isset( $_COOKIE[session_name()] ) || session_id() ) {
3294                 return;
3295         }
3296
3297         // PHP's built-in session entropy is enabled if:
3298         // - entropy_file is set or you're on Windows with php 5.3.3+
3299         // - AND entropy_length is > 0
3300         // We treat it as disabled if it doesn't have an entropy length of at least 32
3301         $entropyEnabled = wfCheckEntropy();
3302
3303         // If built-in entropy is not enabled or not sufficient override PHP's
3304         // built in session id generation code
3305         if ( !$entropyEnabled ) {
3306                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, " .
3307                         "overriding session id generation using our cryptrand source.\n" );
3308                 session_id( MWCryptRand::generateHex( 32 ) );
3309         }
3310 }
3311
3312 /**
3313  * Reset the session_id
3314  *
3315  * @since 1.22
3316  */
3317 function wfResetSessionID() {
3318         global $wgCookieSecure;
3319         $oldSessionId = session_id();
3320         $cookieParams = session_get_cookie_params();
3321         if ( wfCheckEntropy() && $wgCookieSecure == $cookieParams['secure'] ) {
3322                 session_regenerate_id( false );
3323         } else {
3324                 $tmp = $_SESSION;
3325                 session_destroy();
3326                 wfSetupSession( MWCryptRand::generateHex( 32 ) );
3327                 $_SESSION = $tmp;
3328         }
3329         $newSessionId = session_id();
3330 }
3331
3332 /**
3333  * Initialise php session
3334  *
3335  * @param bool $sessionId
3336  */
3337 function wfSetupSession( $sessionId = false ) {
3338         global $wgSessionsInObjectCache, $wgSessionHandler;
3339         global $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
3340
3341         if ( $wgSessionsInObjectCache ) {
3342                 ObjectCacheSessionHandler::install();
3343         } elseif ( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3344                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3345                 # hasn't already been set to the desired value (that causes errors)
3346                 ini_set( 'session.save_handler', $wgSessionHandler );
3347         }
3348
3349         session_set_cookie_params(
3350                 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
3351         session_cache_limiter( 'private, must-revalidate' );
3352         if ( $sessionId ) {
3353                 session_id( $sessionId );
3354         } else {
3355                 wfFixSessionID();
3356         }
3357
3358         MediaWiki\suppressWarnings();
3359         session_start();
3360         MediaWiki\restoreWarnings();
3361
3362         if ( $wgSessionsInObjectCache ) {
3363                 ObjectCacheSessionHandler::renewCurrentSession();
3364         }
3365 }
3366
3367 /**
3368  * Get an object from the precompiled serialized directory
3369  *
3370  * @param string $name
3371  * @return mixed The variable on success, false on failure
3372  */
3373 function wfGetPrecompiledData( $name ) {
3374         global $IP;
3375
3376         $file = "$IP/serialized/$name";
3377         if ( file_exists( $file ) ) {
3378                 $blob = file_get_contents( $file );
3379                 if ( $blob ) {
3380                         return unserialize( $blob );
3381                 }
3382         }
3383         return false;
3384 }
3385
3386 /**
3387  * Make a cache key for the local wiki.
3388  *
3389  * @param string $args,...
3390  * @return string
3391  */
3392 function wfMemcKey( /*...*/ ) {
3393         return call_user_func_array(
3394                 array( ObjectCache::getLocalClusterInstance(), 'makeKey' ),
3395                 func_get_args()
3396         );
3397 }
3398
3399 /**
3400  * Make a cache key for a foreign DB.
3401  *
3402  * Must match what wfMemcKey() would produce in context of the foreign wiki.
3403  *
3404  * @param string $db
3405  * @param string $prefix
3406  * @param string $args,...
3407  * @return string
3408  */
3409 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
3410         $args = array_slice( func_get_args(), 2 );
3411         $keyspace = $prefix ? "$db-$prefix" : $db;
3412         return call_user_func_array(
3413                 array( ObjectCache::getLocalClusterInstance(), 'makeKeyInternal' ),
3414                 array( $keyspace, $args )
3415         );
3416 }
3417
3418 /**
3419  * Make a cache key with database-agnostic prefix.
3420  *
3421  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
3422  * instead. Must have a prefix as otherwise keys that use a database name
3423  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
3424  *
3425  * @since 1.26
3426  * @param string $args,...
3427  * @return string
3428  */
3429 function wfGlobalCacheKey( /*...*/ ) {
3430         return call_user_func_array(
3431                 array( ObjectCache::getLocalClusterInstance(), 'makeGlobalKey' ),
3432                 func_get_args()
3433         );
3434 }
3435
3436 /**
3437  * Get an ASCII string identifying this wiki
3438  * This is used as a prefix in memcached keys
3439  *
3440  * @return string
3441  */
3442 function wfWikiID() {
3443         global $wgDBprefix, $wgDBname;
3444         if ( $wgDBprefix ) {
3445                 return "$wgDBname-$wgDBprefix";
3446         } else {
3447                 return $wgDBname;
3448         }
3449 }
3450
3451 /**
3452  * Split a wiki ID into DB name and table prefix
3453  *
3454  * @param string $wiki
3455  *
3456  * @return array
3457  */
3458 function wfSplitWikiID( $wiki ) {
3459         $bits = explode( '-', $wiki, 2 );
3460         if ( count( $bits ) < 2 ) {
3461                 $bits[] = '';
3462         }
3463         return $bits;
3464 }
3465
3466 /**
3467  * Get a Database object.
3468  *
3469  * @param int $db Index of the connection to get. May be DB_MASTER for the
3470  *            master (for write queries), DB_SLAVE for potentially lagged read
3471  *            queries, or an integer >= 0 for a particular server.
3472  *
3473  * @param string|string[] $groups Query groups. An array of group names that this query
3474  *                belongs to. May contain a single string if the query is only
3475  *                in one group.
3476  *
3477  * @param string|bool $wiki The wiki ID, or false for the current wiki
3478  *
3479  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3480  * will always return the same object, unless the underlying connection or load
3481  * balancer is manually destroyed.
3482  *
3483  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3484  * updater to ensure that a proper database is being updated.
3485  *
3486  * @return DatabaseBase
3487  */
3488 function wfGetDB( $db, $groups = array(), $wiki = false ) {
3489         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3490 }
3491
3492 /**
3493  * Get a load balancer object.
3494  *
3495  * @param string|bool $wiki Wiki ID, or false for the current wiki
3496  * @return LoadBalancer
3497  */
3498 function wfGetLB( $wiki = false ) {
3499         return wfGetLBFactory()->getMainLB( $wiki );
3500 }
3501
3502 /**
3503  * Get the load balancer factory object
3504  *
3505  * @return LBFactory
3506  */
3507 function wfGetLBFactory() {
3508         return LBFactory::singleton();
3509 }
3510
3511 /**
3512  * Find a file.
3513  * Shortcut for RepoGroup::singleton()->findFile()
3514  *
3515  * @param string $title String or Title object
3516  * @param array $options Associative array of options (see RepoGroup::findFile)
3517  * @return File|bool File, or false if the file does not exist
3518  */
3519 function wfFindFile( $title, $options = array() ) {
3520         return RepoGroup::singleton()->findFile( $title, $options );
3521 }
3522
3523 /**
3524  * Get an object referring to a locally registered file.
3525  * Returns a valid placeholder object if the file does not exist.
3526  *
3527  * @param Title|string $title
3528  * @return LocalFile|null A File, or null if passed an invalid Title
3529  */
3530 function wfLocalFile( $title ) {
3531         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3532 }
3533
3534 /**
3535  * Should low-performance queries be disabled?
3536  *
3537  * @return bool
3538  * @codeCoverageIgnore
3539  */
3540 function wfQueriesMustScale() {
3541         global $wgMiserMode;
3542         return $wgMiserMode
3543                 || ( SiteStats::pages() > 100000
3544                 && SiteStats::edits() > 1000000
3545                 && SiteStats::users() > 10000 );
3546 }
3547
3548 /**
3549  * Get the path to a specified script file, respecting file
3550  * extensions; this is a wrapper around $wgScriptPath etc.
3551  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3552  *
3553  * @param string $script Script filename, sans extension
3554  * @return string
3555  */
3556 function wfScript( $script = 'index' ) {
3557         global $wgScriptPath, $wgScript, $wgLoadScript;
3558         if ( $script === 'index' ) {
3559                 return $wgScript;
3560         } elseif ( $script === 'load' ) {
3561                 return $wgLoadScript;
3562         } else {
3563                 return "{$wgScriptPath}/{$script}.php";
3564         }
3565 }
3566
3567 /**
3568  * Get the script URL.
3569  *
3570  * @return string Script URL
3571  */
3572 function wfGetScriptUrl() {
3573         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3574                 /* as it was called, minus the query string.
3575                  *
3576                  * Some sites use Apache rewrite rules to handle subdomains,
3577                  * and have PHP set up in a weird way that causes PHP_SELF
3578                  * to contain the rewritten URL instead of the one that the
3579                  * outside world sees.
3580                  *
3581                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
3582                  * provides containing the "before" URL.
3583                  */
3584                 return $_SERVER['SCRIPT_NAME'];
3585         } else {
3586                 return $_SERVER['URL'];
3587         }
3588 }
3589
3590 /**
3591  * Convenience function converts boolean values into "true"
3592  * or "false" (string) values
3593  *
3594  * @param bool $value
3595  * @return string
3596  */
3597 function wfBoolToStr( $value ) {
3598         return $value ? 'true' : 'false';
3599 }
3600
3601 /**
3602  * Get a platform-independent path to the null file, e.g. /dev/null
3603  *
3604  * @return string
3605  */
3606 function wfGetNull() {
3607         return wfIsWindows() ? 'NUL' : '/dev/null';
3608 }
3609
3610 /**
3611  * Waits for the slaves to catch up to the master position
3612  *
3613  * Use this when updating very large numbers of rows, as in maintenance scripts,
3614  * to avoid causing too much lag. Of course, this is a no-op if there are no slaves.
3615  *
3616  * By default this waits on the main DB cluster of the current wiki.
3617  * If $cluster is set to "*" it will wait on all DB clusters, including
3618  * external ones. If the lag being waiting on is caused by the code that
3619  * does this check, it makes since to use $ifWritesSince, particularly if
3620  * cluster is "*", to avoid excess overhead.
3621  *
3622  * Never call this function after a big DB write that is still in a transaction.
3623  * This only makes sense after the possible lag inducing changes were committed.
3624  *
3625  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
3626  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
3627  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
3628  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
3629  * @return bool Success (able to connect and no timeouts reached)
3630  */
3631 function wfWaitForSlaves(
3632         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3633 ) {
3634         // B/C: first argument used to be "max seconds of lag"; ignore such values
3635         $ifWritesSince = ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null;
3636
3637         if ( $timeout === null ) {
3638                 $timeout = ( PHP_SAPI === 'cli' ) ? 86400 : 10;
3639         }
3640
3641         // Figure out which clusters need to be checked
3642         /** @var LoadBalancer[] $lbs */
3643         $lbs = array();
3644         if ( $cluster === '*' ) {
3645                 wfGetLBFactory()->forEachLB( function ( LoadBalancer $lb ) use ( &$lbs ) {
3646                         $lbs[] = $lb;
3647                 } );
3648         } elseif ( $cluster !== false ) {
3649                 $lbs[] = wfGetLBFactory()->getExternalLB( $cluster );
3650         } else {
3651                 $lbs[] = wfGetLB( $wiki );
3652         }
3653
3654         // Get all the master positions of applicable DBs right now.
3655         // This can be faster since waiting on one cluster reduces the
3656         // time needed to wait on the next clusters.
3657         $masterPositions = array_fill( 0, count( $lbs ), false );
3658         foreach ( $lbs as $i => $lb ) {
3659                 if ( $lb->getServerCount() <= 1 ) {
3660                         // Bug 27975 - Don't try to wait for slaves if there are none
3661                         // Prevents permission error when getting master position
3662                         continue;
3663                 } elseif ( $ifWritesSince && $lb->lastMasterChangeTimestamp() < $ifWritesSince ) {
3664                         continue; // no writes since the last wait
3665                 }
3666                 $masterPositions[$i] = $lb->getMasterPos();
3667         }
3668
3669         $ok = true;
3670         foreach ( $lbs as $i => $lb ) {
3671                 if ( $masterPositions[$i] ) {
3672                         // The DBMS may not support getMasterPos() or the whole
3673                         // load balancer might be fake (e.g. $wgAllDBsAreLocalhost).
3674                         $ok = $lb->waitForAll( $masterPositions[$i], $timeout ) && $ok;
3675                 }
3676         }
3677
3678         return $ok;
3679 }
3680
3681 /**
3682  * Count down from $seconds to zero on the terminal, with a one-second pause
3683  * between showing each number. For use in command-line scripts.
3684  *
3685  * @codeCoverageIgnore
3686  * @param int $seconds
3687  */
3688 function wfCountDown( $seconds ) {
3689         for ( $i = $seconds; $i >= 0; $i-- ) {
3690                 if ( $i != $seconds ) {
3691                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3692                 }
3693                 echo $i;
3694                 flush();
3695                 if ( $i ) {
3696                         sleep( 1 );
3697                 }
3698         }
3699         echo "\n";
3700 }
3701
3702 /**
3703  * Replace all invalid characters with -
3704  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3705  * By default, $wgIllegalFileChars = ':'
3706  *
3707  * @param string $name Filename to process
3708  * @return string
3709  */
3710 function wfStripIllegalFilenameChars( $name ) {
3711         global $wgIllegalFileChars;
3712         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3713         $name = wfBaseName( $name );
3714         $name = preg_replace(
3715                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3716                 '-',
3717                 $name
3718         );
3719         return $name;
3720 }
3721
3722 /**
3723  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3724  *
3725  * @return int Resulting value of the memory limit.
3726  */
3727 function wfMemoryLimit() {
3728         global $wgMemoryLimit;
3729         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3730         if ( $memlimit != -1 ) {
3731                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3732                 if ( $conflimit == -1 ) {
3733                         wfDebug( "Removing PHP's memory limit\n" );
3734                         MediaWiki\suppressWarnings();
3735                         ini_set( 'memory_limit', $conflimit );
3736                         MediaWiki\restoreWarnings();
3737                         return $conflimit;
3738                 } elseif ( $conflimit > $memlimit ) {
3739                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3740                         MediaWiki\suppressWarnings();
3741                         ini_set( 'memory_limit', $conflimit );
3742                         MediaWiki\restoreWarnings();
3743                         return $conflimit;
3744                 }
3745         }
3746         return $memlimit;
3747 }
3748
3749 /**
3750  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3751  *
3752  * @return int Prior time limit
3753  * @since 1.26
3754  */
3755 function wfTransactionalTimeLimit() {
3756         global $wgTransactionalTimeLimit;
3757
3758         $timeLimit = ini_get( 'max_execution_time' );
3759         // Note that CLI scripts use 0
3760         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3761                 set_time_limit( $wgTransactionalTimeLimit );
3762         }
3763
3764         ignore_user_abort( true ); // ignore client disconnects
3765
3766         return $timeLimit;
3767 }
3768
3769 /**
3770  * Converts shorthand byte notation to integer form
3771  *
3772  * @param string $string
3773  * @param int $default Returned if $string is empty
3774  * @return int
3775  */
3776 function wfShorthandToInteger( $string = '', $default = -1 ) {
3777         $string = trim( $string );
3778         if ( $string === '' ) {
3779                 return $default;
3780         }
3781         $last = $string[strlen( $string ) - 1];
3782         $val = intval( $string );
3783         switch ( $last ) {
3784                 case 'g':
3785                 case 'G':
3786                         $val *= 1024;
3787                         // break intentionally missing
3788                 case 'm':
3789                 case 'M':
3790                         $val *= 1024;
3791                         // break intentionally missing
3792                 case 'k':
3793                 case 'K':
3794                         $val *= 1024;
3795         }
3796
3797         return $val;
3798 }
3799
3800 /**
3801  * Get the normalised IETF language tag
3802  * See unit test for examples.
3803  *
3804  * @param string $code The language code.
3805  * @return string The language code which complying with BCP 47 standards.
3806  */
3807 function wfBCP47( $code ) {
3808         $codeSegment = explode( '-', $code );
3809         $codeBCP = array();
3810         foreach ( $codeSegment as $segNo => $seg ) {
3811                 // when previous segment is x, it is a private segment and should be lc
3812                 if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3813                         $codeBCP[$segNo] = strtolower( $seg );
3814                 // ISO 3166 country code
3815                 } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3816                         $codeBCP[$segNo] = strtoupper( $seg );
3817                 // ISO 15924 script code
3818                 } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3819                         $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3820                 // Use lowercase for other cases
3821                 } else {
3822                         $codeBCP[$segNo] = strtolower( $seg );
3823                 }
3824         }
3825         $langCode = implode( '-', $codeBCP );
3826         return $langCode;
3827 }
3828
3829 /**
3830  * Get a specific cache object.
3831  *
3832  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3833  * @return BagOStuff
3834  */
3835 function wfGetCache( $cacheType ) {
3836         return ObjectCache::getInstance( $cacheType );
3837 }
3838
3839 /**
3840  * Get the main cache object
3841  *
3842  * @return BagOStuff
3843  */
3844 function wfGetMainCache() {
3845         global $wgMainCacheType;
3846         return ObjectCache::getInstance( $wgMainCacheType );
3847 }
3848
3849 /**
3850  * Get the cache object used by the message cache
3851  *
3852  * @return BagOStuff
3853  */
3854 function wfGetMessageCacheStorage() {
3855         global $wgMessageCacheType;
3856         return ObjectCache::getInstance( $wgMessageCacheType );
3857 }
3858
3859 /**
3860  * Get the cache object used by the parser cache
3861  *
3862  * @return BagOStuff
3863  */
3864 function wfGetParserCacheStorage() {
3865         global $wgParserCacheType;
3866         return ObjectCache::getInstance( $wgParserCacheType );
3867 }
3868
3869 /**
3870  * Call hook functions defined in $wgHooks
3871  *
3872  * @param string $event Event name
3873  * @param array $args Parameters passed to hook functions
3874  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3875  *
3876  * @return bool True if no handler aborted the hook
3877  * @deprecated 1.25 - use Hooks::run
3878  */
3879 function wfRunHooks( $event, array $args = array(), $deprecatedVersion = null ) {
3880         return Hooks::run( $event, $args, $deprecatedVersion );
3881 }
3882
3883 /**
3884  * Wrapper around php's unpack.
3885  *
3886  * @param string $format The format string (See php's docs)
3887  * @param string $data A binary string of binary data
3888  * @param int|bool $length The minimum length of $data or false. This is to
3889  *      prevent reading beyond the end of $data. false to disable the check.
3890  *
3891  * Also be careful when using this function to read unsigned 32 bit integer
3892  * because php might make it negative.
3893  *
3894  * @throws MWException If $data not long enough, or if unpack fails
3895  * @return array Associative array of the extracted data
3896  */
3897 function wfUnpack( $format, $data, $length = false ) {
3898         if ( $length !== false ) {
3899                 $realLen = strlen( $data );
3900                 if ( $realLen < $length ) {
3901                         throw new MWException( "Tried to use wfUnpack on a "
3902                                 . "string of length $realLen, but needed one "
3903                                 . "of at least length $length."
3904                         );
3905                 }
3906         }
3907
3908         MediaWiki\suppressWarnings();
3909         $result = unpack( $format, $data );
3910         MediaWiki\restoreWarnings();
3911
3912         if ( $result === false ) {
3913                 // If it cannot extract the packed data.
3914                 throw new MWException( "unpack could not unpack binary data" );
3915         }
3916         return $result;
3917 }
3918
3919 /**
3920  * Determine if an image exists on the 'bad image list'.
3921  *
3922  * The format of MediaWiki:Bad_image_list is as follows:
3923  *    * Only list items (lines starting with "*") are considered
3924  *    * The first link on a line must be a link to a bad image
3925  *    * Any subsequent links on the same line are considered to be exceptions,
3926  *      i.e. articles where the image may occur inline.
3927  *
3928  * @param string $name The image name to check
3929  * @param Title|bool $contextTitle The page on which the image occurs, if known
3930  * @param string $blacklist Wikitext of a file blacklist
3931  * @return bool
3932  */
3933 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3934         # Handle redirects; callers almost always hit wfFindFile() anyway,
3935         # so just use that method because it has a fast process cache.
3936         $file = wfFindFile( $name ); // get the final name
3937         $name = $file ? $file->getTitle()->getDBkey() : $name;
3938
3939         # Run the extension hook
3940         $bad = false;
3941         if ( !Hooks::run( 'BadImage', array( $name, &$bad ) ) ) {
3942                 return $bad;
3943         }
3944
3945         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3946         $key = wfMemcKey( 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist ) );
3947         $badImages = $cache->get( $key );
3948
3949         if ( $badImages === false ) { // cache miss
3950                 if ( $blacklist === null ) {
3951                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3952                 }
3953                 # Build the list now
3954                 $badImages = array();
3955                 $lines = explode( "\n", $blacklist );
3956                 foreach ( $lines as $line ) {
3957                         # List items only
3958                         if ( substr( $line, 0, 1 ) !== '*' ) {
3959                                 continue;
3960                         }
3961
3962                         # Find all links
3963                         $m = array();
3964                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3965                                 continue;
3966                         }
3967
3968                         $exceptions = array();
3969                         $imageDBkey = false;
3970                         foreach ( $m[1] as $i => $titleText ) {
3971                                 $title = Title::newFromText( $titleText );
3972                                 if ( !is_null( $title ) ) {
3973                                         if ( $i == 0 ) {
3974                                                 $imageDBkey = $title->getDBkey();
3975                                         } else {
3976                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3977                                         }
3978                                 }
3979                         }
3980
3981                         if ( $imageDBkey !== false ) {
3982                                 $badImages[$imageDBkey] = $exceptions;
3983                         }
3984                 }
3985                 $cache->set( $key, $badImages, 60 );
3986         }
3987
3988         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3989         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3990
3991         return $bad;
3992 }
3993
3994 /**
3995  * Determine whether the client at a given source IP is likely to be able to
3996  * access the wiki via HTTPS.
3997  *
3998  * @param string $ip The IPv4/6 address in the normal human-readable form
3999  * @return bool
4000  */
4001 function wfCanIPUseHTTPS( $ip ) {
4002         $canDo = true;
4003         Hooks::run( 'CanIPUseHTTPS', array( $ip, &$canDo ) );
4004         return !!$canDo;
4005 }
4006
4007 /**
4008  * Determine input string is represents as infinity
4009  *
4010  * @param string $str The string to determine
4011  * @return bool
4012  * @since 1.25
4013  */
4014 function wfIsInfinity( $str ) {
4015         $infinityValues = array( 'infinite', 'indefinite', 'infinity', 'never' );
4016         return in_array( $str, $infinityValues );
4017 }
4018
4019 /**
4020  * Returns true if these thumbnail parameters match one that MediaWiki
4021  * requests from file description pages and/or parser output.
4022  *
4023  * $params is considered non-standard if they involve a non-standard
4024  * width or any non-default parameters aside from width and page number.
4025  * The number of possible files with standard parameters is far less than
4026  * that of all combinations; rate-limiting for them can thus be more generious.
4027  *
4028  * @param File $file
4029  * @param array $params
4030  * @return bool
4031  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
4032  */
4033 function wfThumbIsStandard( File $file, array $params ) {
4034         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
4035
4036         $multipliers = array( 1 );
4037         if ( $wgResponsiveImages ) {
4038                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
4039                 // @see Linker::processResponsiveImages
4040                 $multipliers[] = 1.5;
4041                 $multipliers[] = 2;
4042         }
4043
4044         $handler = $file->getHandler();
4045         if ( !$handler || !isset( $params['width'] ) ) {
4046                 return false;
4047         }
4048
4049         $basicParams = array();
4050         if ( isset( $params['page'] ) ) {
4051                 $basicParams['page'] = $params['page'];
4052         }
4053
4054         $thumbLimits = array();
4055         $imageLimits = array();
4056         // Expand limits to account for multipliers
4057         foreach ( $multipliers as $multiplier ) {
4058                 $thumbLimits = array_merge( $thumbLimits, array_map(
4059                         function ( $width ) use ( $multiplier ) {
4060                                 return round( $width * $multiplier );
4061                         }, $wgThumbLimits )
4062                 );
4063                 $imageLimits = array_merge( $imageLimits, array_map(
4064                         function ( $pair ) use ( $multiplier ) {
4065                                 return array(
4066                                         round( $pair[0] * $multiplier ),
4067                                         round( $pair[1] * $multiplier ),
4068                                 );
4069                         }, $wgImageLimits )
4070                 );
4071         }
4072
4073         // Check if the width matches one of $wgThumbLimits
4074         if ( in_array( $params['width'], $thumbLimits ) ) {
4075                 $normalParams = $basicParams + array( 'width' => $params['width'] );
4076                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
4077                 $handler->normaliseParams( $file, $normalParams );
4078         } else {
4079                 // If not, then check if the width matchs one of $wgImageLimits
4080                 $match = false;
4081                 foreach ( $imageLimits as $pair ) {
4082                         $normalParams = $basicParams + array( 'width' => $pair[0], 'height' => $pair[1] );
4083                         // Decide whether the thumbnail should be scaled on width or height.
4084                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
4085                         $handler->normaliseParams( $file, $normalParams );
4086                         // Check if this standard thumbnail size maps to the given width
4087                         if ( $normalParams['width'] == $params['width'] ) {
4088                                 $match = true;
4089                                 break;
4090                         }
4091                 }
4092                 if ( !$match ) {
4093                         return false; // not standard for description pages
4094                 }
4095         }
4096
4097         // Check that the given values for non-page, non-width, params are just defaults
4098         foreach ( $params as $key => $value ) {
4099                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
4100                         return false;
4101                 }
4102         }
4103
4104         return true;
4105 }
4106
4107 /**
4108  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
4109  *
4110  * Values that exist in both values will be combined with += (all values of the array
4111  * of $newValues will be added to the values of the array of $baseArray, while values,
4112  * that exists in both, the value of $baseArray will be used).
4113  *
4114  * @param array $baseArray The array where you want to add the values of $newValues to
4115  * @param array $newValues An array with new values
4116  * @return array The combined array
4117  * @since 1.26
4118  */
4119 function wfArrayPlus2d( array $baseArray, array $newValues ) {
4120         // First merge items that are in both arrays
4121         foreach ( $baseArray as $name => &$groupVal ) {
4122                 if ( isset( $newValues[$name] ) ) {
4123                         $groupVal += $newValues[$name];
4124                 }
4125         }
4126         // Now add items that didn't exist yet
4127         $baseArray += $newValues;
4128
4129         return $baseArray;
4130 }