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                         # @todo FIXME: Sometimes get nested arrays for $params,
 312                         # which leads to E_NOTICEs
 313                         $spec = implode( "\t", $params );
 314                         $out[$spec] = $params;
 315                 }
 316         }
 317         return array_values( $out );
 318 }
 319
 320 /**
 321  * Insert array into another array after the specified *KEY*
 322  *
 323  * @param array $array The array.
 324  * @param array $insert The array to insert.
 325  * @param mixed $after The key to insert after
 326  * @return array
 327  */
 328 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 329         // Find the offset of the element to insert after.
 330         $keys = array_keys( $array );
 331         $offsetByKey = array_flip( $keys );
 332
 333         $offset = $offsetByKey[$after];
 334
 335         // Insert at the specified offset
 336         $before = array_slice( $array, 0, $offset + 1, true );
 337         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 338
 339         $output = $before + $insert + $after;
 340
 341         return $output;
 342 }
 343
 344 /**
 345  * Recursively converts the parameter (an object) to an array with the same data
 346  *
 347  * @param object|array $objOrArray
 348  * @param bool $recursive
 349  * @return array
 350  */
 351 function wfObjectToArray( $objOrArray, $recursive = true ) {
 352         $array = array();
 353         if ( is_object( $objOrArray ) ) {
 354                 $objOrArray = get_object_vars( $objOrArray );
 355         }
 356         foreach ( $objOrArray as $key => $value ) {
 357                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 358                         $value = wfObjectToArray( $value );
 359                 }
 360
 361                 $array[$key] = $value;
 362         }
 363
 364         return $array;
 365 }
 366
 367 /**
 368  * Get a random decimal value between 0 and 1, in a way
 369  * not likely to give duplicate values for any realistic
 370  * number of articles.
 371  *
 372  * @return string
 373  */
 374 function wfRandom() {
 375         # The maximum random value is "only" 2^31-1, so get two random
 376         # values to reduce the chance of dupes
 377         $max = mt_getrandmax() + 1;
 378         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 379
 380         return $rand;
 381 }
 382
 383 /**
 384  * Get a random string containing a number of pseudo-random hex
 385  * characters.
 386  * @note This is not secure, if you are trying to generate some sort
 387  *       of token please use MWCryptRand instead.
 388  *
 389  * @param int $length The length of the string to generate
 390  * @return string
 391  * @since 1.20
 392  */
 393 function wfRandomString( $length = 32 ) {
 394         $str = '';
 395         for ( $n = 0; $n < $length; $n += 7 ) {
 396                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 397         }
 398         return substr( $str, 0, $length );
 399 }
 400
 401 /**
 402  * We want some things to be included as literal characters in our title URLs
 403  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 404  * all of the following should be safe:
 405  *
 406  * ;:@&=$-_.+!*'(),
 407  *
 408  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 409  * character which should not be encoded. More importantly, google chrome
 410  * always converts %7E back to ~, and converting it in this function can
 411  * cause a redirect loop (T105265).
 412  *
 413  * But + is not safe because it's used to indicate a space; &= are only safe in
 414  * paths and not in queries (and we don't distinguish here); ' seems kind of
 415  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 416  * is reserved, we don't care.  So the list we unescape is:
 417  *
 418  * ;:@$!*(),/~
 419  *
 420  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 421  * so no fancy : for IIS7.
 422  *
 423  * %2F in the page titles seems to fatally break for some reason.
 424  *
 425  * @param string $s
 426  * @return string
 427  */
 428 function wfUrlencode( $s ) {
 429         static $needle;
 430
 431         if ( is_null( $s ) ) {
 432                 $needle = null;
 433                 return '';
 434         }
 435
 436         if ( is_null( $needle ) ) {
 437                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' );
 438                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 439                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 440                 ) {
 441                         $needle[] = '%3A';
 442                 }
 443         }
 444
 445         $s = urlencode( $s );
 446         $s = str_ireplace(
 447                 $needle,
 448                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ),
 449                 $s
 450         );
 451
 452         return $s;
 453 }
 454
 455 /**
 456  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 457  * "days=7&limit=100". Options in the first array override options in the second.
 458  * Options set to null or false will not be output.
 459  *
 460  * @param array $array1 ( String|Array )
 461  * @param array $array2 ( String|Array )
 462  * @param string $prefix
 463  * @return string
 464  */
 465 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 466         if ( !is_null( $array2 ) ) {
 467                 $array1 = $array1 + $array2;
 468         }
 469
 470         $cgi = '';
 471         foreach ( $array1 as $key => $value ) {
 472                 if ( !is_null( $value ) && $value !== false ) {
 473                         if ( $cgi != '' ) {
 474                                 $cgi .= '&';
 475                         }
 476                         if ( $prefix !== '' ) {
 477                                 $key = $prefix . "[$key]";
 478                         }
 479                         if ( is_array( $value ) ) {
 480                                 $firstTime = true;
 481                                 foreach ( $value as $k => $v ) {
 482                                         $cgi .= $firstTime ? '' : '&';
 483                                         if ( is_array( $v ) ) {
 484                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 485                                         } else {
 486                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 487                                         }
 488                                         $firstTime = false;
 489                                 }
 490                         } else {
 491                                 if ( is_object( $value ) ) {
 492                                         $value = $value->__toString();
 493                                 }
 494                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 495                         }
 496                 }
 497         }
 498         return $cgi;
 499 }
 500
 501 /**
 502  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 503  * its argument and returns the same string in array form.  This allows compatibility
 504  * with legacy functions that accept raw query strings instead of nice
 505  * arrays.  Of course, keys and values are urldecode()d.
 506  *
 507  * @param string $query Query string
 508  * @return string[] Array version of input
 509  */
 510 function wfCgiToArray( $query ) {
 511         if ( isset( $query[0] ) && $query[0] == '?' ) {
 512                 $query = substr( $query, 1 );
 513         }
 514         $bits = explode( '&', $query );
 515         $ret = array();
 516         foreach ( $bits as $bit ) {
 517                 if ( $bit === '' ) {
 518                         continue;
 519                 }
 520                 if ( strpos( $bit, '=' ) === false ) {
 521                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 522                         $key = $bit;
 523                         $value = '';
 524                 } else {
 525                         list( $key, $value ) = explode( '=', $bit );
 526                 }
 527                 $key = urldecode( $key );
 528                 $value = urldecode( $value );
 529                 if ( strpos( $key, '[' ) !== false ) {
 530                         $keys = array_reverse( explode( '[', $key ) );
 531                         $key = array_pop( $keys );
 532                         $temp = $value;
 533                         foreach ( $keys as $k ) {
 534                                 $k = substr( $k, 0, -1 );
 535                                 $temp = array( $k => $temp );
 536                         }
 537                         if ( isset( $ret[$key] ) ) {
 538                                 $ret[$key] = array_merge( $ret[$key], $temp );
 539                         } else {
 540                                 $ret[$key] = $temp;
 541                         }
 542                 } else {
 543                         $ret[$key] = $value;
 544                 }
 545         }
 546         return $ret;
 547 }
 548
 549 /**
 550  * Append a query string to an existing URL, which may or may not already
 551  * have query string parameters already. If so, they will be combined.
 552  *
 553  * @param string $url
 554  * @param string|string[] $query String or associative array
 555  * @return string
 556  */
 557 function wfAppendQuery( $url, $query ) {
 558         if ( is_array( $query ) ) {
 559                 $query = wfArrayToCgi( $query );
 560         }
 561         if ( $query != '' ) {
 562                 if ( false === strpos( $url, '?' ) ) {
 563                         $url .= '?';
 564                 } else {
 565                         $url .= '&';
 566                 }
 567                 $url .= $query;
 568         }
 569         return $url;
 570 }
 571
 572 /**
 573  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 574  * is correct.
 575  *
 576  * The meaning of the PROTO_* constants is as follows:
 577  * PROTO_HTTP: Output a URL starting with http://
 578  * PROTO_HTTPS: Output a URL starting with https://
 579  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 580  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 581  *    on which protocol was used for the current incoming request
 582  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 583  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 584  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 585  *
 586  * @todo this won't work with current-path-relative URLs
 587  * like "subdir/foo.html", etc.
 588  *
 589  * @param string $url Either fully-qualified or a local path + query
 590  * @param string $defaultProto One of the PROTO_* constants. Determines the
 591  *    protocol to use if $url or $wgServer is protocol-relative
 592  * @return string Fully-qualified URL, current-path-relative URL or false if
 593  *    no valid URL can be constructed
 594  */
 595 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 596         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 597                 $wgHttpsPort;
 598         if ( $defaultProto === PROTO_CANONICAL ) {
 599                 $serverUrl = $wgCanonicalServer;
 600         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 601                 // Make $wgInternalServer fall back to $wgServer if not set
 602                 $serverUrl = $wgInternalServer;
 603         } else {
 604                 $serverUrl = $wgServer;
 605                 if ( $defaultProto === PROTO_CURRENT ) {
 606                         $defaultProto = $wgRequest->getProtocol() . '://';
 607                 }
 608         }
 609
 610         // Analyze $serverUrl to obtain its protocol
 611         $bits = wfParseUrl( $serverUrl );
 612         $serverHasProto = $bits && $bits['scheme'] != '';
 613
 614         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 615                 if ( $serverHasProto ) {
 616                         $defaultProto = $bits['scheme'] . '://';
 617                 } else {
 618                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 619                         // This really isn't supposed to happen. Fall back to HTTP in this
 620                         // ridiculous case.
 621                         $defaultProto = PROTO_HTTP;
 622                 }
 623         }
 624
 625         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 626
 627         if ( substr( $url, 0, 2 ) == '//' ) {
 628                 $url = $defaultProtoWithoutSlashes . $url;
 629         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 630                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 631                 // otherwise leave it alone.
 632                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 633         }
 634
 635         $bits = wfParseUrl( $url );
 636
 637         // ensure proper port for HTTPS arrives in URL
 638         // https://phabricator.wikimedia.org/T67184
 639         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 640                 $bits['port'] = $wgHttpsPort;
 641         }
 642
 643         if ( $bits && isset( $bits['path'] ) ) {
 644                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 645                 return wfAssembleUrl( $bits );
 646         } elseif ( $bits ) {
 647                 # No path to expand
 648                 return $url;
 649         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 650                 # URL is a relative path
 651                 return wfRemoveDotSegments( $url );
 652         }
 653
 654         # Expanded URL is not valid.
 655         return false;
 656 }
 657
 658 /**
 659  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 660  * if you need to edit part of a URL and put it back together.
 661  *
 662  * This is the basic structure used (brackets contain keys for $urlParts):
 663  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 664  *
 665  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 666  *
 667  * @since 1.19
 668  * @param array $urlParts URL parts, as output from wfParseUrl
 669  * @return string URL assembled from its component parts
 670  */
 671 function wfAssembleUrl( $urlParts ) {
 672         $result = '';
 673
 674         if ( isset( $urlParts['delimiter'] ) ) {
 675                 if ( isset( $urlParts['scheme'] ) ) {
 676                         $result .= $urlParts['scheme'];
 677                 }
 678
 679                 $result .= $urlParts['delimiter'];
 680         }
 681
 682         if ( isset( $urlParts['host'] ) ) {
 683                 if ( isset( $urlParts['user'] ) ) {
 684                         $result .= $urlParts['user'];
 685                         if ( isset( $urlParts['pass'] ) ) {
 686                                 $result .= ':' . $urlParts['pass'];
 687                         }
 688                         $result .= '@';
 689                 }
 690
 691                 $result .= $urlParts['host'];
 692
 693                 if ( isset( $urlParts['port'] ) ) {
 694                         $result .= ':' . $urlParts['port'];
 695                 }
 696         }
 697
 698         if ( isset( $urlParts['path'] ) ) {
 699                 $result .= $urlParts['path'];
 700         }
 701
 702         if ( isset( $urlParts['query'] ) ) {
 703                 $result .= '?' . $urlParts['query'];
 704         }
 705
 706         if ( isset( $urlParts['fragment'] ) ) {
 707                 $result .= '#' . $urlParts['fragment'];
 708         }
 709
 710         return $result;
 711 }
 712
 713 /**
 714  * Remove all dot-segments in the provided URL path.  For example,
 715  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 716  * RFC3986 section 5.2.4.
 717  *
 718  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 719  *
 720  * @param string $urlPath URL path, potentially containing dot-segments
 721  * @return string URL path with all dot-segments removed
 722  */
 723 function wfRemoveDotSegments( $urlPath ) {
 724         $output = '';
 725         $inputOffset = 0;
 726         $inputLength = strlen( $urlPath );
 727
 728         while ( $inputOffset < $inputLength ) {
 729                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 730                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 731                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 732                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 733                 $trimOutput = false;
 734
 735                 if ( $prefixLengthTwo == './' ) {
 736                         # Step A, remove leading "./"
 737                         $inputOffset += 2;
 738                 } elseif ( $prefixLengthThree == '../' ) {
 739                         # Step A, remove leading "../"
 740                         $inputOffset += 3;
 741                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 742                         # Step B, replace leading "/.$" with "/"
 743                         $inputOffset += 1;
 744                         $urlPath[$inputOffset] = '/';
 745                 } elseif ( $prefixLengthThree == '/./' ) {
 746                         # Step B, replace leading "/./" with "/"
 747                         $inputOffset += 2;
 748                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 749                         # Step C, replace leading "/..$" with "/" and
 750                         # remove last path component in output
 751                         $inputOffset += 2;
 752                         $urlPath[$inputOffset] = '/';
 753                         $trimOutput = true;
 754                 } elseif ( $prefixLengthFour == '/../' ) {
 755                         # Step C, replace leading "/../" with "/" and
 756                         # remove last path component in output
 757                         $inputOffset += 3;
 758                         $trimOutput = true;
 759                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 760                         # Step D, remove "^.$"
 761                         $inputOffset += 1;
 762                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 763                         # Step D, remove "^..$"
 764                         $inputOffset += 2;
 765                 } else {
 766                         # Step E, move leading path segment to output
 767                         if ( $prefixLengthOne == '/' ) {
 768                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 769                         } else {
 770                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 771                         }
 772                         if ( $slashPos === false ) {
 773                                 $output .= substr( $urlPath, $inputOffset );
 774                                 $inputOffset = $inputLength;
 775                         } else {
 776                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 777                                 $inputOffset += $slashPos - $inputOffset;
 778                         }
 779                 }
 780
 781                 if ( $trimOutput ) {
 782                         $slashPos = strrpos( $output, '/' );
 783                         if ( $slashPos === false ) {
 784                                 $output = '';
 785                         } else {
 786                                 $output = substr( $output, 0, $slashPos );
 787                         }
 788                 }
 789         }
 790
 791         return $output;
 792 }
 793
 794 /**
 795  * Returns a regular expression of url protocols
 796  *
 797  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 798  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 799  * @return string
 800  */
 801 function wfUrlProtocols( $includeProtocolRelative = true ) {
 802         global $wgUrlProtocols;
 803
 804         // Cache return values separately based on $includeProtocolRelative
 805         static $withProtRel = null, $withoutProtRel = null;
 806         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 807         if ( !is_null( $cachedValue ) ) {
 808                 return $cachedValue;
 809         }
 810
 811         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 812         // with LocalSettings files from 1.5
 813         if ( is_array( $wgUrlProtocols ) ) {
 814                 $protocols = array();
 815                 foreach ( $wgUrlProtocols as $protocol ) {
 816                         // Filter out '//' if !$includeProtocolRelative
 817                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 818                                 $protocols[] = preg_quote( $protocol, '/' );
 819                         }
 820                 }
 821
 822                 $retval = implode( '|', $protocols );
 823         } else {
 824                 // Ignore $includeProtocolRelative in this case
 825                 // This case exists for pre-1.6 compatibility, and we can safely assume
 826                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 827                 // URLs weren't supported until 1.18
 828                 $retval = $wgUrlProtocols;
 829         }
 830
 831         // Cache return value
 832         if ( $includeProtocolRelative ) {
 833                 $withProtRel = $retval;
 834         } else {
 835                 $withoutProtRel = $retval;
 836         }
 837         return $retval;
 838 }
 839
 840 /**
 841  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 842  * you need a regex that matches all URL protocols but does not match protocol-
 843  * relative URLs
 844  * @return string
 845  */
 846 function wfUrlProtocolsWithoutProtRel() {
 847         return wfUrlProtocols( false );
 848 }
 849
 850 /**
 851  * parse_url() work-alike, but non-broken.  Differences:
 852  *
 853  * 1) Does not raise warnings on bad URLs (just returns false).
 854  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 855  *    protocol-relative URLs) correctly.
 856  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2)).
 857  *
 858  * @param string $url A URL to parse
 859  * @return string[] Bits of the URL in an associative array, per PHP docs
 860  */
 861 function wfParseUrl( $url ) {
 862         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 863
 864         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 865         // bad that the easiest way to handle them is to just prepend 'http:' and
 866         // strip the protocol out later.
 867         $wasRelative = substr( $url, 0, 2 ) == '//';
 868         if ( $wasRelative ) {
 869                 $url = "http:$url";
 870         }
 871         MediaWiki\suppressWarnings();
 872         $bits = parse_url( $url );
 873         MediaWiki\restoreWarnings();
 874         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 875         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 876         if ( !$bits || !isset( $bits['scheme'] ) ) {
 877                 return false;
 878         }
 879
 880         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 881         $bits['scheme'] = strtolower( $bits['scheme'] );
 882
 883         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 884         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 885                 $bits['delimiter'] = '://';
 886         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 887                 $bits['delimiter'] = ':';
 888                 // parse_url detects for news: and mailto: the host part of an url as path
 889                 // We have to correct this wrong detection
 890                 if ( isset( $bits['path'] ) ) {
 891                         $bits['host'] = $bits['path'];
 892                         $bits['path'] = '';
 893                 }
 894         } else {
 895                 return false;
 896         }
 897
 898         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 899         if ( !isset( $bits['host'] ) ) {
 900                 $bits['host'] = '';
 901
 902                 // bug 45069
 903                 if ( isset( $bits['path'] ) ) {
 904                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 905                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 906                                 $bits['path'] = '/' . $bits['path'];
 907                         }
 908                 } else {
 909                         $bits['path'] = '';
 910                 }
 911         }
 912
 913         // If the URL was protocol-relative, fix scheme and delimiter
 914         if ( $wasRelative ) {
 915                 $bits['scheme'] = '';
 916                 $bits['delimiter'] = '//';
 917         }
 918         return $bits;
 919 }
 920
 921 /**
 922  * Take a URL, make sure it's expanded to fully qualified, and replace any
 923  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 924  * for more compact display and legibility for local audiences.
 925  *
 926  * @todo handle punycode domains too
 927  *
 928  * @param string $url
 929  * @return string
 930  */
 931 function wfExpandIRI( $url ) {
 932         return preg_replace_callback(
 933                 '/((?:%[89A-F][0-9A-F])+)/i',
 934                 'wfExpandIRI_callback',
 935                 wfExpandUrl( $url )
 936         );
 937 }
 938
 939 /**
 940  * Private callback for wfExpandIRI
 941  * @param array $matches
 942  * @return string
 943  */
 944 function wfExpandIRI_callback( $matches ) {
 945         return urldecode( $matches[1] );
 946 }
 947
 948 /**
 949  * Make URL indexes, appropriate for the el_index field of externallinks.
 950  *
 951  * @param string $url
 952  * @return array
 953  */
 954 function wfMakeUrlIndexes( $url ) {
 955         $bits = wfParseUrl( $url );
 956
 957         // Reverse the labels in the hostname, convert to lower case
 958         // For emails reverse domainpart only
 959         if ( $bits['scheme'] == 'mailto' ) {
 960                 $mailparts = explode( '@', $bits['host'], 2 );
 961                 if ( count( $mailparts ) === 2 ) {
 962                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 963                 } else {
 964                         // No domain specified, don't mangle it
 965                         $domainpart = '';
 966                 }
 967                 $reversedHost = $domainpart . '@' . $mailparts[0];
 968         } else {
 969                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 970         }
 971         // Add an extra dot to the end
 972         // Why? Is it in wrong place in mailto links?
 973         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 974                 $reversedHost .= '.';
 975         }
 976         // Reconstruct the pseudo-URL
 977         $prot = $bits['scheme'];
 978         $index = $prot . $bits['delimiter'] . $reversedHost;
 979         // Leave out user and password. Add the port, path, query and fragment
 980         if ( isset( $bits['port'] ) ) {
 981                 $index .= ':' . $bits['port'];
 982         }
 983         if ( isset( $bits['path'] ) ) {
 984                 $index .= $bits['path'];
 985         } else {
 986                 $index .= '/';
 987         }
 988         if ( isset( $bits['query'] ) ) {
 989                 $index .= '?' . $bits['query'];
 990         }
 991         if ( isset( $bits['fragment'] ) ) {
 992                 $index .= '#' . $bits['fragment'];
 993         }
 994
 995         if ( $prot == '' ) {
 996                 return array( "http:$index", "https:$index" );
 997         } else {
 998                 return array( $index );
 999         }
1000 }
1001
1002 /**
1003  * Check whether a given URL has a domain that occurs in a given set of domains
1004  * @param string $url URL
1005  * @param array $domains Array of domains (strings)
1006  * @return bool True if the host part of $url ends in one of the strings in $domains
1007  */
1008 function wfMatchesDomainList( $url, $domains ) {
1009         $bits = wfParseUrl( $url );
1010         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1011                 $host = '.' . $bits['host'];
1012                 foreach ( (array)$domains as $domain ) {
1013                         $domain = '.' . $domain;
1014                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1015                                 return true;
1016                         }
1017                 }
1018         }
1019         return false;
1020 }
1021
1022 /**
1023  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1024  * In normal operation this is a NOP.
1025  *
1026  * Controlling globals:
1027  * $wgDebugLogFile - points to the log file
1028  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1029  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1030  *
1031  * @since 1.25 support for additional context data
1032  *
1033  * @param string $text
1034  * @param string|bool $dest Unused
1035  * @param array $context Additional logging context data
1036  */
1037 function wfDebug( $text, $dest = 'all', array $context = array() ) {
1038         global $wgDebugRawPage, $wgDebugLogPrefix;
1039         global $wgDebugTimestamps, $wgRequestTime;
1040
1041         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1042                 return;
1043         }
1044
1045         $text = trim( $text );
1046
1047         // Inline logic from deprecated wfDebugTimer()
1048         if ( $wgDebugTimestamps ) {
1049                 $context['seconds_elapsed'] = sprintf(
1050                         '%6.4f',
1051                         microtime( true ) - $wgRequestTime
1052                 );
1053                 $context['memory_used'] = sprintf(
1054                         '%5.1fM',
1055                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1056                 );
1057         }
1058
1059         if ( $wgDebugLogPrefix !== '' ) {
1060                 $context['prefix'] = $wgDebugLogPrefix;
1061         }
1062
1063         $logger = LoggerFactory::getInstance( 'wfDebug' );
1064         $logger->debug( $text, $context );
1065 }
1066
1067 /**
1068  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1069  * @return bool
1070  */
1071 function wfIsDebugRawPage() {
1072         static $cache;
1073         if ( $cache !== null ) {
1074                 return $cache;
1075         }
1076         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1077         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1078                 || (
1079                         isset( $_SERVER['SCRIPT_NAME'] )
1080                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1081                 )
1082         ) {
1083                 $cache = true;
1084         } else {
1085                 $cache = false;
1086         }
1087         return $cache;
1088 }
1089
1090 /**
1091  * Get microsecond timestamps for debug logs
1092  *
1093  * @deprecated since 1.25
1094  * @return string
1095  */
1096 function wfDebugTimer() {
1097         global $wgDebugTimestamps, $wgRequestTime;
1098
1099         wfDeprecated( __METHOD__, '1.25' );
1100
1101         if ( !$wgDebugTimestamps ) {
1102                 return '';
1103         }
1104
1105         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
1106         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
1107         return "$prefix $mem  ";
1108 }
1109
1110 /**
1111  * Send a line giving PHP memory usage.
1112  *
1113  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1114  */
1115 function wfDebugMem( $exact = false ) {
1116         $mem = memory_get_usage();
1117         if ( !$exact ) {
1118                 $mem = floor( $mem / 1024 ) . ' KiB';
1119         } else {
1120                 $mem .= ' B';
1121         }
1122         wfDebug( "Memory usage: $mem\n" );
1123 }
1124
1125 /**
1126  * Send a line to a supplementary debug log file, if configured, or main debug
1127  * log if not.
1128  *
1129  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1130  * a string filename or an associative array mapping 'destination' to the
1131  * desired filename. The associative array may also contain a 'sample' key
1132  * with an integer value, specifying a sampling factor. Sampled log events
1133  * will be emitted with a 1 in N random chance.
1134  *
1135  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1136  * @since 1.25 support for additional context data
1137  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1138  *
1139  * @param string $logGroup
1140  * @param string $text
1141  * @param string|bool $dest Destination of the message:
1142  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1143  *     - 'log': only to the log and not in HTML
1144  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1145  *       discarded otherwise
1146  *   For backward compatibility, it can also take a boolean:
1147  *     - true: same as 'all'
1148  *     - false: same as 'private'
1149  * @param array $context Additional logging context data
1150  */
1151 function wfDebugLog(
1152         $logGroup, $text, $dest = 'all', array $context = array()
1153 ) {
1154         // Turn $dest into a string if it's a boolean (for b/c)
1155         if ( $dest === true ) {
1156                 $dest = 'all';
1157         } elseif ( $dest === false ) {
1158                 $dest = 'private';
1159         }
1160
1161         $text = trim( $text );
1162
1163         $logger = LoggerFactory::getInstance( $logGroup );
1164         $context['private'] = ( $dest === 'private' );
1165         $logger->info( $text, $context );
1166 }
1167
1168 /**
1169  * Log for database errors
1170  *
1171  * @since 1.25 support for additional context data
1172  *
1173  * @param string $text Database error message.
1174  * @param array $context Additional logging context data
1175  */
1176 function wfLogDBError( $text, array $context = array() ) {
1177         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1178         $logger->error( trim( $text ), $context );
1179 }
1180
1181 /**
1182  * Throws a warning that $function is deprecated
1183  *
1184  * @param string $function
1185  * @param string|bool $version Version of MediaWiki that the function
1186  *    was deprecated in (Added in 1.19).
1187  * @param string|bool $component Added in 1.19.
1188  * @param int $callerOffset How far up the call stack is the original
1189  *    caller. 2 = function that called the function that called
1190  *    wfDeprecated (Added in 1.20)
1191  *
1192  * @return null
1193  */
1194 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1195         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1196 }
1197
1198 /**
1199  * Send a warning either to the debug log or in a PHP error depending on
1200  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1201  *
1202  * @param string $msg Message to send
1203  * @param int $callerOffset Number of items to go back in the backtrace to
1204  *        find the correct caller (1 = function calling wfWarn, ...)
1205  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1206  *        only used when $wgDevelopmentWarnings is true
1207  */
1208 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1209         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1210 }
1211
1212 /**
1213  * Send a warning as a PHP error and the debug log. This is intended for logging
1214  * warnings in production. For logging development warnings, use WfWarn instead.
1215  *
1216  * @param string $msg Message to send
1217  * @param int $callerOffset Number of items to go back in the backtrace to
1218  *        find the correct caller (1 = function calling wfLogWarning, ...)
1219  * @param int $level PHP error level; defaults to E_USER_WARNING
1220  */
1221 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1222         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1223 }
1224
1225 /**
1226  * Log to a file without getting "file size exceeded" signals.
1227  *
1228  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1229  * send lines to the specified port, prefixed by the specified prefix and a space.
1230  * @since 1.25 support for additional context data
1231  *
1232  * @param string $text
1233  * @param string $file Filename
1234  * @param array $context Additional logging context data
1235  * @throws MWException
1236  * @deprecated since 1.25 Use MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1237  */
1238 function wfErrorLog( $text, $file, array $context = array() ) {
1239         wfDeprecated( __METHOD__, '1.25' );
1240         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1241         $context['destination'] = $file;
1242         $logger->info( trim( $text ), $context );
1243 }
1244
1245 /**
1246  * @todo document
1247  */
1248 function wfLogProfilingData() {
1249         global $wgDebugLogGroups, $wgDebugRawPage;
1250
1251         $context = RequestContext::getMain();
1252         $request = $context->getRequest();
1253
1254         $profiler = Profiler::instance();
1255         $profiler->setContext( $context );
1256         $profiler->logData();
1257
1258         $config = $context->getConfig();
1259         if ( $config->get( 'StatsdServer' ) ) {
1260                 try {
1261                         $statsdServer = explode( ':', $config->get( 'StatsdServer' ) );
1262                         $statsdHost = $statsdServer[0];
1263                         $statsdPort = isset( $statsdServer[1] ) ? $statsdServer[1] : 8125;
1264                         $statsdSender = new SocketSender( $statsdHost, $statsdPort );
1265                         $statsdClient = new SamplingStatsdClient( $statsdSender, true, false );
1266                         $statsdClient->send( $context->getStats()->getBuffer() );
1267                 } catch ( Exception $ex ) {
1268                         MWExceptionHandler::logException( $ex );
1269                 }
1270         }
1271
1272         # Profiling must actually be enabled...
1273         if ( $profiler instanceof ProfilerStub ) {
1274                 return;
1275         }
1276
1277         if ( isset( $wgDebugLogGroups['profileoutput'] )
1278                 && $wgDebugLogGroups['profileoutput'] === false
1279         ) {
1280                 // Explicitly disabled
1281                 return;
1282         }
1283         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1284                 return;
1285         }
1286
1287         $ctx = array( 'elapsed' => $request->getElapsedTime() );
1288         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1289                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1290         }
1291         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1292                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1293         }
1294         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1295                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1296         }
1297         if ( isset( $ctx['forwarded_for'] ) ||
1298                 isset( $ctx['client_ip'] ) ||
1299                 isset( $ctx['from'] ) ) {
1300                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1301         }
1302
1303         // Don't load $wgUser at this late stage just for statistics purposes
1304         // @todo FIXME: We can detect some anons even if it is not loaded.
1305         // See User::getId()
1306         $user = $context->getUser();
1307         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1308
1309         // Command line script uses a FauxRequest object which does not have
1310         // any knowledge about an URL and throw an exception instead.
1311         try {
1312                 $ctx['url'] = urldecode( $request->getRequestURL() );
1313         } catch ( Exception $ignored ) {
1314                 // no-op
1315         }
1316
1317         $ctx['output'] = $profiler->getOutput();
1318
1319         $log = LoggerFactory::getInstance( 'profileoutput' );
1320         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1321 }
1322
1323 /**
1324  * Increment a statistics counter
1325  *
1326  * @param string $key
1327  * @param int $count
1328  * @return void
1329  */
1330 function wfIncrStats( $key, $count = 1 ) {
1331         $stats = RequestContext::getMain()->getStats();
1332         $stats->updateCount( $key, $count );
1333 }
1334
1335 /**
1336  * Check whether the wiki is in read-only mode.
1337  *
1338  * @return bool
1339  */
1340 function wfReadOnly() {
1341         return wfReadOnlyReason() !== false;
1342 }
1343
1344 /**
1345  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1346  *
1347  * @return string|bool String when in read-only mode; false otherwise
1348  */
1349 function wfReadOnlyReason() {
1350         global $wgReadOnly, $wgReadOnlyFile;
1351
1352         if ( $wgReadOnly === null ) {
1353                 // Set $wgReadOnly for faster access next time
1354                 if ( is_file( $wgReadOnlyFile ) && filesize( $wgReadOnlyFile ) > 0 ) {
1355                         $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1356                 } else {
1357                         $wgReadOnly = false;
1358                 }
1359                 // Callers use this method to be aware that data presented to a user
1360                 // may be very stale and thus allowing submissions can be problematic.
1361                 try {
1362                         if ( $wgReadOnly === false && wfGetLB()->getLaggedSlaveMode() ) {
1363                                 $wgReadOnly = 'The database has been automatically locked ' .
1364                                         'while the slave database servers catch up to the master';
1365                         }
1366                 } catch ( DBConnectionError $e ) {
1367                         $wgReadOnly = 'The database has been automatically locked ' .
1368                                 'until the slave database servers become available';
1369                 }
1370         }
1371
1372         return $wgReadOnly;
1373 }
1374
1375 /**
1376  * Return a Language object from $langcode
1377  *
1378  * @param Language|string|bool $langcode Either:
1379  *                  - a Language object
1380  *                  - code of the language to get the message for, if it is
1381  *                    a valid code create a language for that language, if
1382  *                    it is a string but not a valid code then make a basic
1383  *                    language object
1384  *                  - a boolean: if it's false then use the global object for
1385  *                    the current user's language (as a fallback for the old parameter
1386  *                    functionality), or if it is true then use global object
1387  *                    for the wiki's content language.
1388  * @return Language
1389  */
1390 function wfGetLangObj( $langcode = false ) {
1391         # Identify which language to get or create a language object for.
1392         # Using is_object here due to Stub objects.
1393         if ( is_object( $langcode ) ) {
1394                 # Great, we already have the object (hopefully)!
1395                 return $langcode;
1396         }
1397
1398         global $wgContLang, $wgLanguageCode;
1399         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1400                 # $langcode is the language code of the wikis content language object.
1401                 # or it is a boolean and value is true
1402                 return $wgContLang;
1403         }
1404
1405         global $wgLang;
1406         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1407                 # $langcode is the language code of user language object.
1408                 # or it was a boolean and value is false
1409                 return $wgLang;
1410         }
1411
1412         $validCodes = array_keys( Language::fetchLanguageNames() );
1413         if ( in_array( $langcode, $validCodes ) ) {
1414                 # $langcode corresponds to a valid language.
1415                 return Language::factory( $langcode );
1416         }
1417
1418         # $langcode is a string, but not a valid language code; use content language.
1419         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1420         return $wgContLang;
1421 }
1422
1423 /**
1424  * This is the function for getting translated interface messages.
1425  *
1426  * @see Message class for documentation how to use them.
1427  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1428  *
1429  * This function replaces all old wfMsg* functions.
1430  *
1431  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1432  * @param mixed $params,... Normal message parameters
1433  * @return Message
1434  *
1435  * @since 1.17
1436  *
1437  * @see Message::__construct
1438  */
1439 function wfMessage( $key /*...*/ ) {
1440         $params = func_get_args();
1441         array_shift( $params );
1442         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1443                 $params = $params[0];
1444         }
1445         return new Message( $key, $params );
1446 }
1447
1448 /**
1449  * This function accepts multiple message keys and returns a message instance
1450  * for the first message which is non-empty. If all messages are empty then an
1451  * instance of the first message key is returned.
1452  *
1453  * @param string|string[] $keys,... Message keys
1454  * @return Message
1455  *
1456  * @since 1.18
1457  *
1458  * @see Message::newFallbackSequence
1459  */
1460 function wfMessageFallback( /*...*/ ) {
1461         $args = func_get_args();
1462         return call_user_func_array( 'Message::newFallbackSequence', $args );
1463 }
1464
1465 /**
1466  * Get a message from anywhere, for the current user language.
1467  *
1468  * Use wfMsgForContent() instead if the message should NOT
1469  * change depending on the user preferences.
1470  *
1471  * @deprecated since 1.18
1472  *
1473  * @param string $key Lookup key for the message, usually
1474  *    defined in languages/Language.php
1475  *
1476  * Parameters to the message, which can be used to insert variable text into
1477  * it, can be passed to this function in the following formats:
1478  * - One per argument, starting at the second parameter
1479  * - As an array in the second parameter
1480  * These are not shown in the function definition.
1481  *
1482  * @return string
1483  */
1484 function wfMsg( $key ) {
1485         wfDeprecated( __METHOD__, '1.21' );
1486
1487         $args = func_get_args();
1488         array_shift( $args );
1489         return wfMsgReal( $key, $args );
1490 }
1491
1492 /**
1493  * Same as above except doesn't transform the message
1494  *
1495  * @deprecated since 1.18
1496  *
1497  * @param string $key
1498  * @return string
1499  */
1500 function wfMsgNoTrans( $key ) {
1501         wfDeprecated( __METHOD__, '1.21' );
1502
1503         $args = func_get_args();
1504         array_shift( $args );
1505         return wfMsgReal( $key, $args, true, false, false );
1506 }
1507
1508 /**
1509  * Get a message from anywhere, for the current global language
1510  * set with $wgLanguageCode.
1511  *
1512  * Use this if the message should NOT change dependent on the
1513  * language set in the user's preferences. This is the case for
1514  * most text written into logs, as well as link targets (such as
1515  * the name of the copyright policy page). Link titles, on the
1516  * other hand, should be shown in the UI language.
1517  *
1518  * Note that MediaWiki allows users to change the user interface
1519  * language in their preferences, but a single installation
1520  * typically only contains content in one language.
1521  *
1522  * Be wary of this distinction: If you use wfMsg() where you should
1523  * use wfMsgForContent(), a user of the software may have to
1524  * customize potentially hundreds of messages in
1525  * order to, e.g., fix a link in every possible language.
1526  *
1527  * @deprecated since 1.18
1528  *
1529  * @param string $key Lookup key for the message, usually
1530  *     defined in languages/Language.php
1531  * @return string
1532  */
1533 function wfMsgForContent( $key ) {
1534         wfDeprecated( __METHOD__, '1.21' );
1535
1536         global $wgForceUIMsgAsContentMsg;
1537         $args = func_get_args();
1538         array_shift( $args );
1539         $forcontent = true;
1540         if ( is_array( $wgForceUIMsgAsContentMsg )
1541                 && in_array( $key, $wgForceUIMsgAsContentMsg )
1542         ) {
1543                 $forcontent = false;
1544         }
1545         return wfMsgReal( $key, $args, true, $forcontent );
1546 }
1547
1548 /**
1549  * Same as above except doesn't transform the message
1550  *
1551  * @deprecated since 1.18
1552  *
1553  * @param string $key
1554  * @return string
1555  */
1556 function wfMsgForContentNoTrans( $key ) {
1557         wfDeprecated( __METHOD__, '1.21' );
1558
1559         global $wgForceUIMsgAsContentMsg;
1560         $args = func_get_args();
1561         array_shift( $args );
1562         $forcontent = true;
1563         if ( is_array( $wgForceUIMsgAsContentMsg )
1564                 && in_array( $key, $wgForceUIMsgAsContentMsg )
1565         ) {
1566                 $forcontent = false;
1567         }
1568         return wfMsgReal( $key, $args, true, $forcontent, false );
1569 }
1570
1571 /**
1572  * Really get a message
1573  *
1574  * @deprecated since 1.18
1575  *
1576  * @param string $key Key to get.
1577  * @param array $args
1578  * @param bool $useDB
1579  * @param string|bool $forContent Language code, or false for user lang, true for content lang.
1580  * @param bool $transform Whether or not to transform the message.
1581  * @return string The requested message.
1582  */
1583 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1584         wfDeprecated( __METHOD__, '1.21' );
1585
1586         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1587         $message = wfMsgReplaceArgs( $message, $args );
1588         return $message;
1589 }
1590
1591 /**
1592  * Fetch a message string value, but don't replace any keys yet.
1593  *
1594  * @deprecated since 1.18
1595  *
1596  * @param string $key
1597  * @param bool $useDB
1598  * @param string|bool $langCode Code of the language to get the message for, or
1599  *   behaves as a content language switch if it is a boolean.
1600  * @param bool $transform Whether to parse magic words, etc.
1601  * @return string
1602  */
1603 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1604         wfDeprecated( __METHOD__, '1.21' );
1605
1606         Hooks::run( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1607
1608         $cache = MessageCache::singleton();
1609         $message = $cache->get( $key, $useDB, $langCode );
1610         if ( $message === false ) {
1611                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1612         } elseif ( $transform ) {
1613                 $message = $cache->transform( $message );
1614         }
1615         return $message;
1616 }
1617
1618 /**
1619  * Replace message parameter keys on the given formatted output.
1620  *
1621  * @param string $message
1622  * @param array $args
1623  * @return string
1624  * @private
1625  */
1626 function wfMsgReplaceArgs( $message, $args ) {
1627         # Fix windows line-endings
1628         # Some messages are split with explode("\n", $msg)
1629         $message = str_replace( "\r", '', $message );
1630
1631         // Replace arguments
1632         if ( count( $args ) ) {
1633                 if ( is_array( $args[0] ) ) {
1634                         $args = array_values( $args[0] );
1635                 }
1636                 $replacementKeys = array();
1637                 foreach ( $args as $n => $param ) {
1638                         $replacementKeys['$' . ( $n + 1 )] = $param;
1639                 }
1640                 $message = strtr( $message, $replacementKeys );
1641         }
1642
1643         return $message;
1644 }
1645
1646 /**
1647  * Return an HTML-escaped version of a message.
1648  * Parameter replacements, if any, are done *after* the HTML-escaping,
1649  * so parameters may contain HTML (eg links or form controls). Be sure
1650  * to pre-escape them if you really do want plaintext, or just wrap
1651  * the whole thing in htmlspecialchars().
1652  *
1653  * @deprecated since 1.18
1654  *
1655  * @param string $key
1656  * @param string $args,... Parameters
1657  * @return string
1658  */
1659 function wfMsgHtml( $key ) {
1660         wfDeprecated( __METHOD__, '1.21' );
1661
1662         $args = func_get_args();
1663         array_shift( $args );
1664         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1665 }
1666
1667 /**
1668  * Return an HTML version of message
1669  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1670  * so parameters may contain HTML (eg links or form controls). Be sure
1671  * to pre-escape them if you really do want plaintext, or just wrap
1672  * the whole thing in htmlspecialchars().
1673  *
1674  * @deprecated since 1.18
1675  *
1676  * @param string $key
1677  * @param string $args,... Parameters
1678  * @return string
1679  */
1680 function wfMsgWikiHtml( $key ) {
1681         wfDeprecated( __METHOD__, '1.21' );
1682
1683         $args = func_get_args();
1684         array_shift( $args );
1685         return wfMsgReplaceArgs(
1686                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1687                 /* can't be set to false */ true, /* interface */ true )->getText(),
1688                 $args );
1689 }
1690
1691 /**
1692  * Returns message in the requested format
1693  *
1694  * @deprecated since 1.18
1695  *
1696  * @param string $key Key of the message
1697  * @param array $options Processing rules.
1698  *   Can take the following options:
1699  *     parse: parses wikitext to HTML
1700  *     parseinline: parses wikitext to HTML and removes the surrounding
1701  *       p's added by parser or tidy
1702  *     escape: filters message through htmlspecialchars
1703  *     escapenoentities: same, but allows entity references like &#160; through
1704  *     replaceafter: parameters are substituted after parsing or escaping
1705  *     parsemag: transform the message using magic phrases
1706  *     content: fetch message for content language instead of interface
1707  *   Also can accept a single associative argument, of the form 'language' => 'xx':
1708  *     language: Language object or language code to fetch message for
1709  *       (overridden by content).
1710  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1711  *
1712  * @return string
1713  */
1714 function wfMsgExt( $key, $options ) {
1715         wfDeprecated( __METHOD__, '1.21' );
1716
1717         $args = func_get_args();
1718         array_shift( $args );
1719         array_shift( $args );
1720         $options = (array)$options;
1721         $validOptions = array( 'parse', 'parseinline', 'escape', 'escapenoentities', 'replaceafter',
1722                 'parsemag', 'content' );
1723
1724         foreach ( $options as $arrayKey => $option ) {
1725                 if ( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1726                         // An unknown index, neither numeric nor "language"
1727                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1728                 } elseif ( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option, $validOptions ) ) {
1729                         // A numeric index with unknown value
1730                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1731                 }
1732         }
1733
1734         if ( in_array( 'content', $options, true ) ) {
1735                 $forContent = true;
1736                 $langCode = true;
1737                 $langCodeObj = null;
1738         } elseif ( array_key_exists( 'language', $options ) ) {
1739                 $forContent = false;
1740                 $langCode = wfGetLangObj( $options['language'] );
1741                 $langCodeObj = $langCode;
1742         } else {
1743                 $forContent = false;
1744                 $langCode = false;
1745                 $langCodeObj = null;
1746         }
1747
1748         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1749
1750         if ( !in_array( 'replaceafter', $options, true ) ) {
1751                 $string = wfMsgReplaceArgs( $string, $args );
1752         }
1753
1754         $messageCache = MessageCache::singleton();
1755         $parseInline = in_array( 'parseinline', $options, true );
1756         if ( in_array( 'parse', $options, true ) || $parseInline ) {
1757                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1758                 if ( $string instanceof ParserOutput ) {
1759                         $string = $string->getText();
1760                 }
1761
1762                 if ( $parseInline ) {
1763                         $string = Parser::stripOuterParagraph( $string );
1764                 }
1765         } elseif ( in_array( 'parsemag', $options, true ) ) {
1766                 $string = $messageCache->transform( $string,
1767                                 !$forContent, $langCodeObj );
1768         }
1769
1770         if ( in_array( 'escape', $options, true ) ) {
1771                 $string = htmlspecialchars( $string );
1772         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1773                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1774         }
1775
1776         if ( in_array( 'replaceafter', $options, true ) ) {
1777                 $string = wfMsgReplaceArgs( $string, $args );
1778         }
1779
1780         return $string;
1781 }
1782
1783 /**
1784  * Since wfMsg() and co suck, they don't return false if the message key they
1785  * looked up didn't exist but instead the key wrapped in <>'s, this function checks for the
1786  * nonexistence of messages by checking the MessageCache::get() result directly.
1787  *
1788  * @deprecated since 1.18. Use Message::isDisabled().
1789  *
1790  * @param string $key The message key looked up
1791  * @return bool True if the message *doesn't* exist.
1792  */
1793 function wfEmptyMsg( $key ) {
1794         wfDeprecated( __METHOD__, '1.21' );
1795
1796         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1797 }
1798
1799 /**
1800  * Fetch server name for use in error reporting etc.
1801  * Use real server name if available, so we know which machine
1802  * in a server farm generated the current page.
1803  *
1804  * @return string
1805  */
1806 function wfHostname() {
1807         static $host;
1808         if ( is_null( $host ) ) {
1809
1810                 # Hostname overriding
1811                 global $wgOverrideHostname;
1812                 if ( $wgOverrideHostname !== false ) {
1813                         # Set static and skip any detection
1814                         $host = $wgOverrideHostname;
1815                         return $host;
1816                 }
1817
1818                 if ( function_exists( 'posix_uname' ) ) {
1819                         // This function not present on Windows
1820                         $uname = posix_uname();
1821                 } else {
1822                         $uname = false;
1823                 }
1824                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1825                         $host = $uname['nodename'];
1826                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1827                         # Windows computer name
1828                         $host = getenv( 'COMPUTERNAME' );
1829                 } else {
1830                         # This may be a virtual server.
1831                         $host = $_SERVER['SERVER_NAME'];
1832                 }
1833         }
1834         return $host;
1835 }
1836
1837 /**
1838  * Returns a script tag that stores the amount of time it took MediaWiki to
1839  * handle the request in milliseconds as 'wgBackendResponseTime'.
1840  *
1841  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1842  * hostname of the server handling the request.
1843  *
1844  * @return string
1845  */
1846 function wfReportTime() {
1847         global $wgRequestTime, $wgShowHostnames;
1848
1849         $responseTime = round( ( microtime( true ) - $wgRequestTime ) * 1000 );
1850         $reportVars = array( 'wgBackendResponseTime' => $responseTime );
1851         if ( $wgShowHostnames ) {
1852                 $reportVars['wgHostname'] = wfHostname();
1853         }
1854         return Skin::makeVariablesScript( $reportVars );
1855 }
1856
1857 /**
1858  * Safety wrapper for debug_backtrace().
1859  *
1860  * Will return an empty array if debug_backtrace is disabled, otherwise
1861  * the output from debug_backtrace() (trimmed).
1862  *
1863  * @param int $limit This parameter can be used to limit the number of stack frames returned
1864  *
1865  * @return array Array of backtrace information
1866  */
1867 function wfDebugBacktrace( $limit = 0 ) {
1868         static $disabled = null;
1869
1870         if ( is_null( $disabled ) ) {
1871                 $disabled = !function_exists( 'debug_backtrace' );
1872                 if ( $disabled ) {
1873                         wfDebug( "debug_backtrace() is disabled\n" );
1874                 }
1875         }
1876         if ( $disabled ) {
1877                 return array();
1878         }
1879
1880         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1881                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1882         } else {
1883                 return array_slice( debug_backtrace(), 1 );
1884         }
1885 }
1886
1887 /**
1888  * Get a debug backtrace as a string
1889  *
1890  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1891  *   Defaults to $wgCommandLineMode if unset.
1892  * @return string
1893  * @since 1.25 Supports $raw parameter.
1894  */
1895 function wfBacktrace( $raw = null ) {
1896         global $wgCommandLineMode;
1897
1898         if ( $raw === null ) {
1899                 $raw = $wgCommandLineMode;
1900         }
1901
1902         if ( $raw ) {
1903                 $frameFormat = "%s line %s calls %s()\n";
1904                 $traceFormat = "%s";
1905         } else {
1906                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1907                 $traceFormat = "<ul>\n%s</ul>\n";
1908         }
1909
1910         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1911                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1912                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1913                 $call = $frame['function'];
1914                 if ( !empty( $frame['class'] ) ) {
1915                         $call = $frame['class'] . $frame['type'] . $call;
1916                 }
1917                 return sprintf( $frameFormat, $file, $line, $call );
1918         }, wfDebugBacktrace() );
1919
1920         return sprintf( $traceFormat, implode( '', $frames ) );
1921 }
1922
1923 /**
1924  * Get the name of the function which called this function
1925  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1926  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1927  * wfGetCaller( 3 ) is the parent of that.
1928  *
1929  * @param int $level
1930  * @return string
1931  */
1932 function wfGetCaller( $level = 2 ) {
1933         $backtrace = wfDebugBacktrace( $level + 1 );
1934         if ( isset( $backtrace[$level] ) ) {
1935                 return wfFormatStackFrame( $backtrace[$level] );
1936         } else {
1937                 return 'unknown';
1938         }
1939 }
1940
1941 /**
1942  * Return a string consisting of callers in the stack. Useful sometimes
1943  * for profiling specific points.
1944  *
1945  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1946  * @return string
1947  */
1948 function wfGetAllCallers( $limit = 3 ) {
1949         $trace = array_reverse( wfDebugBacktrace() );
1950         if ( !$limit || $limit > count( $trace ) - 1 ) {
1951                 $limit = count( $trace ) - 1;
1952         }
1953         $trace = array_slice( $trace, -$limit - 1, $limit );
1954         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1955 }
1956
1957 /**
1958  * Return a string representation of frame
1959  *
1960  * @param array $frame
1961  * @return string
1962  */
1963 function wfFormatStackFrame( $frame ) {
1964         return isset( $frame['class'] ) ?
1965                 $frame['class'] . '::' . $frame['function'] :
1966                 $frame['function'];
1967 }
1968
1969 /* Some generic result counters, pulled out of SearchEngine */
1970
1971 /**
1972  * @todo document
1973  *
1974  * @param int $offset
1975  * @param int $limit
1976  * @return string
1977  */
1978 function wfShowingResults( $offset, $limit ) {
1979         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1980 }
1981
1982 /**
1983  * @todo document
1984  * @todo FIXME: We may want to blacklist some broken browsers
1985  *
1986  * @param bool $force
1987  * @return bool Whereas client accept gzip compression
1988  */
1989 function wfClientAcceptsGzip( $force = false ) {
1990         static $result = null;
1991         if ( $result === null || $force ) {
1992                 $result = false;
1993                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1994                         # @todo FIXME: We may want to blacklist some broken browsers
1995                         $m = array();
1996                         if ( preg_match(
1997                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1998                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1999                                         $m
2000                                 )
2001                         ) {
2002                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2003                                         $result = false;
2004                                         return $result;
2005                                 }
2006                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2007                                 $result = true;
2008                         }
2009                 }
2010         }
2011         return $result;
2012 }
2013
2014 /**
2015  * Obtain the offset and limit values from the request string;
2016  * used in special pages
2017  *
2018  * @param int $deflimit Default limit if none supplied
2019  * @param string $optionname Name of a user preference to check against
2020  * @return array
2021  * @deprecated since 1.24, just call WebRequest::getLimitOffset() directly
2022  */
2023 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2024         global $wgRequest;
2025         wfDeprecated( __METHOD__, '1.24' );
2026         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2027 }
2028
2029 /**
2030  * Escapes the given text so that it may be output using addWikiText()
2031  * without any linking, formatting, etc. making its way through. This
2032  * is achieved by substituting certain characters with HTML entities.
2033  * As required by the callers, "<nowiki>" is not used.
2034  *
2035  * @param string $text Text to be escaped
2036  * @return string
2037  */
2038 function wfEscapeWikiText( $text ) {
2039         static $repl = null, $repl2 = null;
2040         if ( $repl === null ) {
2041                 $repl = array(
2042                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2043                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2044                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
2045                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
2046                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
2047                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
2048                         "\n " => "\n&#32;", "\r " => "\r&#32;",
2049                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
2050                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
2051                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
2052                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
2053                         '__' => '_&#95;', '://' => '&#58;//',
2054                 );
2055
2056                 // We have to catch everything "\s" matches in PCRE
2057                 foreach ( array( 'ISBN', 'RFC', 'PMID' ) as $magic ) {
2058                         $repl["$magic "] = "$magic&#32;";
2059                         $repl["$magic\t"] = "$magic&#9;";
2060                         $repl["$magic\r"] = "$magic&#13;";
2061                         $repl["$magic\n"] = "$magic&#10;";
2062                         $repl["$magic\f"] = "$magic&#12;";
2063                 }
2064
2065                 // And handle protocols that don't use "://"
2066                 global $wgUrlProtocols;
2067                 $repl2 = array();
2068                 foreach ( $wgUrlProtocols as $prot ) {
2069                         if ( substr( $prot, -1 ) === ':' ) {
2070                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
2071                         }
2072                 }
2073                 $repl2 = $repl2 ? '/\b(' . join( '|', $repl2 ) . '):/i' : '/^(?!)/';
2074         }
2075         $text = substr( strtr( "\n$text", $repl ), 1 );
2076         $text = preg_replace( $repl2, '$1&#58;', $text );
2077         return $text;
2078 }
2079
2080 /**
2081  * Sets dest to source and returns the original value of dest
2082  * If source is NULL, it just returns the value, it doesn't set the variable
2083  * If force is true, it will set the value even if source is NULL
2084  *
2085  * @param mixed $dest
2086  * @param mixed $source
2087  * @param bool $force
2088  * @return mixed
2089  */
2090 function wfSetVar( &$dest, $source, $force = false ) {
2091         $temp = $dest;
2092         if ( !is_null( $source ) || $force ) {
2093                 $dest = $source;
2094         }
2095         return $temp;
2096 }
2097
2098 /**
2099  * As for wfSetVar except setting a bit
2100  *
2101  * @param int $dest
2102  * @param int $bit
2103  * @param bool $state
2104  *
2105  * @return bool
2106  */
2107 function wfSetBit( &$dest, $bit, $state = true ) {
2108         $temp = (bool)( $dest & $bit );
2109         if ( !is_null( $state ) ) {
2110                 if ( $state ) {
2111                         $dest |= $bit;
2112                 } else {
2113                         $dest &= ~$bit;
2114                 }
2115         }
2116         return $temp;
2117 }
2118
2119 /**
2120  * A wrapper around the PHP function var_export().
2121  * Either print it or add it to the regular output ($wgOut).
2122  *
2123  * @param mixed $var A PHP variable to dump.
2124  */
2125 function wfVarDump( $var ) {
2126         global $wgOut;
2127         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2128         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2129                 print $s;
2130         } else {
2131                 $wgOut->addHTML( $s );
2132         }
2133 }
2134
2135 /**
2136  * Provide a simple HTTP error.
2137  *
2138  * @param int|string $code
2139  * @param string $label
2140  * @param string $desc
2141  */
2142 function wfHttpError( $code, $label, $desc ) {
2143         global $wgOut;
2144         HttpStatus::header( $code );
2145         if ( $wgOut ) {
2146                 $wgOut->disable();
2147                 $wgOut->sendCacheControl();
2148         }
2149
2150         header( 'Content-type: text/html; charset=utf-8' );
2151         print '<!DOCTYPE html>' .
2152                 '<html><head><title>' .
2153                 htmlspecialchars( $label ) .
2154                 '</title></head><body><h1>' .
2155                 htmlspecialchars( $label ) .
2156                 '</h1><p>' .
2157                 nl2br( htmlspecialchars( $desc ) ) .
2158                 "</p></body></html>\n";
2159 }
2160
2161 /**
2162  * Clear away any user-level output buffers, discarding contents.
2163  *
2164  * Suitable for 'starting afresh', for instance when streaming
2165  * relatively large amounts of data without buffering, or wanting to
2166  * output image files without ob_gzhandler's compression.
2167  *
2168  * The optional $resetGzipEncoding parameter controls suppression of
2169  * the Content-Encoding header sent by ob_gzhandler; by default it
2170  * is left. See comments for wfClearOutputBuffers() for why it would
2171  * be used.
2172  *
2173  * Note that some PHP configuration options may add output buffer
2174  * layers which cannot be removed; these are left in place.
2175  *
2176  * @param bool $resetGzipEncoding
2177  */
2178 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2179         if ( $resetGzipEncoding ) {
2180                 // Suppress Content-Encoding and Content-Length
2181                 // headers from 1.10+s wfOutputHandler
2182                 global $wgDisableOutputCompression;
2183                 $wgDisableOutputCompression = true;
2184         }
2185         while ( $status = ob_get_status() ) {
2186                 if ( isset( $status['flags'] ) ) {
2187                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
2188                         $deleteable = ( $status['flags'] & $flags ) === $flags;
2189                 } elseif ( isset( $status['del'] ) ) {
2190                         $deleteable = $status['del'];
2191                 } else {
2192                         // Guess that any PHP-internal setting can't be removed.
2193                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
2194                 }
2195                 if ( !$deleteable ) {
2196                         // Give up, and hope the result doesn't break
2197                         // output behavior.
2198                         break;
2199                 }
2200                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
2201                         // Unit testing barrier to prevent this function from breaking PHPUnit.
2202                         break;
2203                 }
2204                 if ( !ob_end_clean() ) {
2205                         // Could not remove output buffer handler; abort now
2206                         // to avoid getting in some kind of infinite loop.
2207                         break;
2208                 }
2209                 if ( $resetGzipEncoding ) {
2210                         if ( $status['name'] == 'ob_gzhandler' ) {
2211                                 // Reset the 'Content-Encoding' field set by this handler
2212                                 // so we can start fresh.
2213                                 header_remove( 'Content-Encoding' );
2214                                 break;
2215                         }
2216                 }
2217         }
2218 }
2219
2220 /**
2221  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2222  *
2223  * Clear away output buffers, but keep the Content-Encoding header
2224  * produced by ob_gzhandler, if any.
2225  *
2226  * This should be used for HTTP 304 responses, where you need to
2227  * preserve the Content-Encoding header of the real result, but
2228  * also need to suppress the output of ob_gzhandler to keep to spec
2229  * and avoid breaking Firefox in rare cases where the headers and
2230  * body are broken over two packets.
2231  */
2232 function wfClearOutputBuffers() {
2233         wfResetOutputBuffers( false );
2234 }
2235
2236 /**
2237  * Converts an Accept-* header into an array mapping string values to quality
2238  * factors
2239  *
2240  * @param string $accept
2241  * @param string $def Default
2242  * @return float[] Associative array of string => float pairs
2243  */
2244 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2245         # No arg means accept anything (per HTTP spec)
2246         if ( !$accept ) {
2247                 return array( $def => 1.0 );
2248         }
2249
2250         $prefs = array();
2251
2252         $parts = explode( ',', $accept );
2253
2254         foreach ( $parts as $part ) {
2255                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2256                 $values = explode( ';', trim( $part ) );
2257                 $match = array();
2258                 if ( count( $values ) == 1 ) {
2259                         $prefs[$values[0]] = 1.0;
2260                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2261                         $prefs[$values[0]] = floatval( $match[1] );
2262                 }
2263         }
2264
2265         return $prefs;
2266 }
2267
2268 /**
2269  * Checks if a given MIME type matches any of the keys in the given
2270  * array. Basic wildcards are accepted in the array keys.
2271  *
2272  * Returns the matching MIME type (or wildcard) if a match, otherwise
2273  * NULL if no match.
2274  *
2275  * @param string $type
2276  * @param array $avail
2277  * @return string
2278  * @private
2279  */
2280 function mimeTypeMatch( $type, $avail ) {
2281         if ( array_key_exists( $type, $avail ) ) {
2282                 return $type;
2283         } else {
2284                 $parts = explode( '/', $type );
2285                 if ( array_key_exists( $parts[0] . '/*', $avail ) ) {
2286                         return $parts[0] . '/*';
2287                 } elseif ( array_key_exists( '*/*', $avail ) ) {
2288                         return '*/*';
2289                 } else {
2290                         return null;
2291                 }
2292         }
2293 }
2294
2295 /**
2296  * Returns the 'best' match between a client's requested internet media types
2297  * and the server's list of available types. Each list should be an associative
2298  * array of type to preference (preference is a float between 0.0 and 1.0).
2299  * Wildcards in the types are acceptable.
2300  *
2301  * @param array $cprefs Client's acceptable type list
2302  * @param array $sprefs Server's offered types
2303  * @return string
2304  *
2305  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2306  * XXX: generalize to negotiate other stuff
2307  */
2308 function wfNegotiateType( $cprefs, $sprefs ) {
2309         $combine = array();
2310
2311         foreach ( array_keys( $sprefs ) as $type ) {
2312                 $parts = explode( '/', $type );
2313                 if ( $parts[1] != '*' ) {
2314                         $ckey = mimeTypeMatch( $type, $cprefs );
2315                         if ( $ckey ) {
2316                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2317                         }
2318                 }
2319         }
2320
2321         foreach ( array_keys( $cprefs ) as $type ) {
2322                 $parts = explode( '/', $type );
2323                 if ( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2324                         $skey = mimeTypeMatch( $type, $sprefs );
2325                         if ( $skey ) {
2326                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2327                         }
2328                 }
2329         }
2330
2331         $bestq = 0;
2332         $besttype = null;
2333
2334         foreach ( array_keys( $combine ) as $type ) {
2335                 if ( $combine[$type] > $bestq ) {
2336                         $besttype = $type;
2337                         $bestq = $combine[$type];
2338                 }
2339         }
2340
2341         return $besttype;
2342 }
2343
2344 /**
2345  * Reference-counted warning suppression
2346  *
2347  * @deprecated since 1.26, use MediaWiki\suppressWarnings() directly
2348  * @param bool $end
2349  */
2350 function wfSuppressWarnings( $end = false ) {
2351         MediaWiki\suppressWarnings( $end );
2352 }
2353
2354 /**
2355  * @deprecated since 1.26, use MediaWiki\restoreWarnings() directly
2356  * Restore error level to previous value
2357  */
2358 function wfRestoreWarnings() {
2359         MediaWiki\suppressWarnings( true );
2360 }
2361
2362 # Autodetect, convert and provide timestamps of various types
2363
2364 /**
2365  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2366  */
2367 define( 'TS_UNIX', 0 );
2368
2369 /**
2370  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2371  */
2372 define( 'TS_MW', 1 );
2373
2374 /**
2375  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2376  */
2377 define( 'TS_DB', 2 );
2378
2379 /**
2380  * RFC 2822 format, for E-mail and HTTP headers
2381  */
2382 define( 'TS_RFC2822', 3 );
2383
2384 /**
2385  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2386  *
2387  * This is used by Special:Export
2388  */
2389 define( 'TS_ISO_8601', 4 );
2390
2391 /**
2392  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2393  *
2394  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2395  *       DateTime tag and page 36 for the DateTimeOriginal and
2396  *       DateTimeDigitized tags.
2397  */
2398 define( 'TS_EXIF', 5 );
2399
2400 /**
2401  * Oracle format time.
2402  */
2403 define( 'TS_ORACLE', 6 );
2404
2405 /**
2406  * Postgres format time.
2407  */
2408 define( 'TS_POSTGRES', 7 );
2409
2410 /**
2411  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2412  */
2413 define( 'TS_ISO_8601_BASIC', 9 );
2414
2415 /**
2416  * Get a timestamp string in one of various formats
2417  *
2418  * @param mixed $outputtype A timestamp in one of the supported formats, the
2419  *   function will autodetect which format is supplied and act accordingly.
2420  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2421  * @return string|bool String / false The same date in the format specified in $outputtype or false
2422  */
2423 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2424         try {
2425                 $timestamp = new MWTimestamp( $ts );
2426                 return $timestamp->getTimestamp( $outputtype );
2427         } catch ( TimestampException $e ) {
2428                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2429                 return false;
2430         }
2431 }
2432
2433 /**
2434  * Return a formatted timestamp, or null if input is null.
2435  * For dealing with nullable timestamp columns in the database.
2436  *
2437  * @param int $outputtype
2438  * @param string $ts
2439  * @return string
2440  */
2441 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2442         if ( is_null( $ts ) ) {
2443                 return null;
2444         } else {
2445                 return wfTimestamp( $outputtype, $ts );
2446         }
2447 }
2448
2449 /**
2450  * Convenience function; returns MediaWiki timestamp for the present time.
2451  *
2452  * @return string
2453  */
2454 function wfTimestampNow() {
2455         # return NOW
2456         return wfTimestamp( TS_MW, time() );
2457 }
2458
2459 /**
2460  * Check if the operating system is Windows
2461  *
2462  * @return bool True if it's Windows, false otherwise.
2463  */
2464 function wfIsWindows() {
2465         static $isWindows = null;
2466         if ( $isWindows === null ) {
2467                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2468         }
2469         return $isWindows;
2470 }
2471
2472 /**
2473  * Check if we are running under HHVM
2474  *
2475  * @return bool
2476  */
2477 function wfIsHHVM() {
2478         return defined( 'HHVM_VERSION' );
2479 }
2480
2481 /**
2482  * Tries to get the system directory for temporary files. First
2483  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2484  * environment variables are then checked in sequence, and if none are
2485  * set try sys_get_temp_dir().
2486  *
2487  * NOTE: When possible, use instead the tmpfile() function to create
2488  * temporary files to avoid race conditions on file creation, etc.
2489  *
2490  * @return string
2491  */
2492 function wfTempDir() {
2493         global $wgTmpDirectory;
2494
2495         if ( $wgTmpDirectory !== false ) {
2496                 return $wgTmpDirectory;
2497         }
2498
2499         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2500
2501         foreach ( $tmpDir as $tmp ) {
2502                 if ( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2503                         return $tmp;
2504                 }
2505         }
2506         return sys_get_temp_dir();
2507 }
2508
2509 /**
2510  * Make directory, and make all parent directories if they don't exist
2511  *
2512  * @param string $dir Full path to directory to create
2513  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2514  * @param string $caller Optional caller param for debugging.
2515  * @throws MWException
2516  * @return bool
2517  */
2518 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2519         global $wgDirectoryMode;
2520
2521         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2522                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2523         }
2524
2525         if ( !is_null( $caller ) ) {
2526                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2527         }
2528
2529         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2530                 return true;
2531         }
2532
2533         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2534
2535         if ( is_null( $mode ) ) {
2536                 $mode = $wgDirectoryMode;
2537         }
2538
2539         // Turn off the normal warning, we're doing our own below
2540         MediaWiki\suppressWarnings();
2541         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2542         MediaWiki\restoreWarnings();
2543
2544         if ( !$ok ) {
2545                 //directory may have been created on another request since we last checked
2546                 if ( is_dir( $dir ) ) {
2547                         return true;
2548                 }
2549
2550                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2551                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2552         }
2553         return $ok;
2554 }
2555
2556 /**
2557  * Remove a directory and all its content.
2558  * Does not hide error.
2559  * @param string $dir
2560  */
2561 function wfRecursiveRemoveDir( $dir ) {
2562         wfDebug( __FUNCTION__ . "( $dir )\n" );
2563         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2564         if ( is_dir( $dir ) ) {
2565                 $objects = scandir( $dir );
2566                 foreach ( $objects as $object ) {
2567                         if ( $object != "." && $object != ".." ) {
2568                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2569                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2570                                 } else {
2571                                         unlink( $dir . '/' . $object );
2572                                 }
2573                         }
2574                 }
2575                 reset( $objects );
2576                 rmdir( $dir );
2577         }
2578 }
2579
2580 /**
2581  * @param int $nr The number to format
2582  * @param int $acc The number of digits after the decimal point, default 2
2583  * @param bool $round Whether or not to round the value, default true
2584  * @return string
2585  */
2586 function wfPercent( $nr, $acc = 2, $round = true ) {
2587         $ret = sprintf( "%.${acc}f", $nr );
2588         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2589 }
2590
2591 /**
2592  * Safety wrapper around ini_get() for boolean settings.
2593  * The values returned from ini_get() are pre-normalized for settings
2594  * set via php.ini or php_flag/php_admin_flag... but *not*
2595  * for those set via php_value/php_admin_value.
2596  *
2597  * It's fairly common for people to use php_value instead of php_flag,
2598  * which can leave you with an 'off' setting giving a false positive
2599  * for code that just takes the ini_get() return value as a boolean.
2600  *
2601  * To make things extra interesting, setting via php_value accepts
2602  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2603  * Unrecognized values go false... again opposite PHP's own coercion
2604  * from string to bool.
2605  *
2606  * Luckily, 'properly' set settings will always come back as '0' or '1',
2607  * so we only have to worry about them and the 'improper' settings.
2608  *
2609  * I frickin' hate PHP... :P
2610  *
2611  * @param string $setting
2612  * @return bool
2613  */
2614 function wfIniGetBool( $setting ) {
2615         $val = strtolower( ini_get( $setting ) );
2616         // 'on' and 'true' can't have whitespace around them, but '1' can.
2617         return $val == 'on'
2618                 || $val == 'true'
2619                 || $val == 'yes'
2620                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2621 }
2622
2623 /**
2624  * Windows-compatible version of escapeshellarg()
2625  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2626  * function puts single quotes in regardless of OS.
2627  *
2628  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2629  * earlier distro releases of PHP)
2630  *
2631  * @param string ... strings to escape and glue together, or a single array of strings parameter
2632  * @return string
2633  */
2634 function wfEscapeShellArg( /*...*/ ) {
2635         wfInitShellLocale();
2636
2637         $args = func_get_args();
2638         if ( count( $args ) === 1 && is_array( reset( $args ) ) ) {
2639                 // If only one argument has been passed, and that argument is an array,
2640                 // treat it as a list of arguments
2641                 $args = reset( $args );
2642         }
2643
2644         $first = true;
2645         $retVal = '';
2646         foreach ( $args as $arg ) {
2647                 if ( !$first ) {
2648                         $retVal .= ' ';
2649                 } else {
2650                         $first = false;
2651                 }
2652
2653                 if ( wfIsWindows() ) {
2654                         // Escaping for an MSVC-style command line parser and CMD.EXE
2655                         // @codingStandardsIgnoreStart For long URLs
2656                         // Refs:
2657                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2658                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2659                         //  * Bug #13518
2660                         //  * CR r63214
2661                         // Double the backslashes before any double quotes. Escape the double quotes.
2662                         // @codingStandardsIgnoreEnd
2663                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2664                         $arg = '';
2665                         $iteration = 0;
2666                         foreach ( $tokens as $token ) {
2667                                 if ( $iteration % 2 == 1 ) {
2668                                         // Delimiter, a double quote preceded by zero or more slashes
2669                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2670                                 } elseif ( $iteration % 4 == 2 ) {
2671                                         // ^ in $token will be outside quotes, need to be escaped
2672                                         $arg .= str_replace( '^', '^^', $token );
2673                                 } else { // $iteration % 4 == 0
2674                                         // ^ in $token will appear inside double quotes, so leave as is
2675                                         $arg .= $token;
2676                                 }
2677                                 $iteration++;
2678                         }
2679                         // Double the backslashes before the end of the string, because
2680                         // we will soon add a quote
2681                         $m = array();
2682                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2683                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2684                         }
2685
2686                         // Add surrounding quotes
2687                         $retVal .= '"' . $arg . '"';
2688                 } else {
2689                         $retVal .= escapeshellarg( $arg );
2690                 }
2691         }
2692         return $retVal;
2693 }
2694
2695 /**
2696  * Check if wfShellExec() is effectively disabled via php.ini config
2697  *
2698  * @return bool|string False or one of (safemode,disabled)
2699  * @since 1.22
2700  */
2701 function wfShellExecDisabled() {
2702         static $disabled = null;
2703         if ( is_null( $disabled ) ) {
2704                 if ( wfIniGetBool( 'safe_mode' ) ) {
2705                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2706                         $disabled = 'safemode';
2707                 } elseif ( !function_exists( 'proc_open' ) ) {
2708                         wfDebug( "proc_open() is disabled\n" );
2709                         $disabled = 'disabled';
2710                 } else {
2711                         $disabled = false;
2712                 }
2713         }
2714         return $disabled;
2715 }
2716
2717 /**
2718  * Execute a shell command, with time and memory limits mirrored from the PHP
2719  * configuration if supported.
2720  *
2721  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2722  *   or an array of unescaped arguments, in which case each value will be escaped
2723  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2724  * @param null|mixed &$retval Optional, will receive the program's exit code.
2725  *   (non-zero is usually failure). If there is an error from
2726  *   read, select, or proc_open(), this will be set to -1.
2727  * @param array $environ Optional environment variables which should be
2728  *   added to the executed command environment.
2729  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2730  *   this overwrites the global wgMaxShell* limits.
2731  * @param array $options Array of options:
2732  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2733  *     including errors from limit.sh
2734  *   - profileMethod: By default this function will profile based on the calling
2735  *     method. Set this to a string for an alternative method to profile from
2736  *
2737  * @return string Collected stdout as a string
2738  */
2739 function wfShellExec( $cmd, &$retval = null, $environ = array(),
2740         $limits = array(), $options = array()
2741 ) {
2742         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2743                 $wgMaxShellWallClockTime, $wgShellCgroup;
2744
2745         $disabled = wfShellExecDisabled();
2746         if ( $disabled ) {
2747                 $retval = 1;
2748                 return $disabled == 'safemode' ?
2749                         'Unable to run external programs in safe mode.' :
2750                         'Unable to run external programs, proc_open() is disabled.';
2751         }
2752
2753         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2754         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2755
2756         wfInitShellLocale();
2757
2758         $envcmd = '';
2759         foreach ( $environ as $k => $v ) {
2760                 if ( wfIsWindows() ) {
2761                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2762                          * appear in the environment variable, so we must use carat escaping as documented in
2763                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2764                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2765                          * are listed there but doesn't appear to need it.
2766                          */
2767                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2768                 } else {
2769                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2770                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2771                          */
2772                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2773                 }
2774         }
2775         if ( is_array( $cmd ) ) {
2776                 $cmd = wfEscapeShellArg( $cmd );
2777         }
2778
2779         $cmd = $envcmd . $cmd;
2780
2781         $useLogPipe = false;
2782         if ( is_executable( '/bin/bash' ) ) {
2783                 $time = intval( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2784                 if ( isset( $limits['walltime'] ) ) {
2785                         $wallTime = intval( $limits['walltime'] );
2786                 } elseif ( isset( $limits['time'] ) ) {
2787                         $wallTime = $time;
2788                 } else {
2789                         $wallTime = intval( $wgMaxShellWallClockTime );
2790                 }
2791                 $mem = intval( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2792                 $filesize = intval( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2793
2794                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2795                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2796                                 escapeshellarg( $cmd ) . ' ' .
2797                                 escapeshellarg(
2798                                         "MW_INCLUDE_STDERR=" . ( $includeStderr ? '1' : '' ) . ';' .
2799                                         "MW_CPU_LIMIT=$time; " .
2800                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2801                                         "MW_MEM_LIMIT=$mem; " .
2802                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2803                                         "MW_WALL_CLOCK_LIMIT=$wallTime; " .
2804                                         "MW_USE_LOG_PIPE=yes"
2805                                 );
2806                         $useLogPipe = true;
2807                 } elseif ( $includeStderr ) {
2808                         $cmd .= ' 2>&1';
2809                 }
2810         } elseif ( $includeStderr ) {
2811                 $cmd .= ' 2>&1';
2812         }
2813         wfDebug( "wfShellExec: $cmd\n" );
2814
2815         $desc = array(
2816                 0 => array( 'file', 'php://stdin', 'r' ),
2817                 1 => array( 'pipe', 'w' ),
2818                 2 => array( 'file', 'php://stderr', 'w' ) );
2819         if ( $useLogPipe ) {
2820                 $desc[3] = array( 'pipe', 'w' );
2821         }
2822         $pipes = null;
2823         $scoped = Profiler::instance()->scopedProfileIn( __FUNCTION__ . '-' . $profileMethod );
2824         $proc = proc_open( $cmd, $desc, $pipes );
2825         if ( !$proc ) {
2826                 wfDebugLog( 'exec', "proc_open() failed: $cmd" );
2827                 $retval = -1;
2828                 return '';
2829         }
2830         $outBuffer = $logBuffer = '';
2831         $emptyArray = array();
2832         $status = false;
2833         $logMsg = false;
2834
2835         // According to the documentation, it is possible for stream_select()
2836         // to fail due to EINTR. I haven't managed to induce this in testing
2837         // despite sending various signals. If it did happen, the error
2838         // message would take the form:
2839         //
2840         // stream_select(): unable to select [4]: Interrupted system call (max_fd=5)
2841         //
2842         // where [4] is the value of the macro EINTR and "Interrupted system
2843         // call" is string which according to the Linux manual is "possibly"
2844         // localised according to LC_MESSAGES.
2845         $eintr = defined( 'SOCKET_EINTR' ) ? SOCKET_EINTR : 4;
2846         $eintrMessage = "stream_select(): unable to select [$eintr]";
2847
2848         // Build a table mapping resource IDs to pipe FDs to work around a
2849         // PHP 5.3 issue in which stream_select() does not preserve array keys
2850         // <https://bugs.php.net/bug.php?id=53427>.
2851         $fds = array();
2852         foreach ( $pipes as $fd => $pipe ) {
2853                 $fds[(int)$pipe] = $fd;
2854         }
2855
2856         $running = true;
2857         $timeout = null;
2858         $numReadyPipes = 0;
2859
2860         while ( $running === true || $numReadyPipes !== 0 ) {
2861                 if ( $running ) {
2862                         $status = proc_get_status( $proc );
2863                         // If the process has terminated, switch to nonblocking selects
2864                         // for getting any data still waiting to be read.
2865                         if ( !$status['running'] ) {
2866                                 $running = false;
2867                                 $timeout = 0;
2868                         }
2869                 }
2870
2871                 $readyPipes = $pipes;
2872
2873                 // Clear last error
2874                 // @codingStandardsIgnoreStart Generic.PHP.NoSilencedErrors.Discouraged
2875                 @trigger_error( '' );
2876                 $numReadyPipes = @stream_select( $readyPipes, $emptyArray, $emptyArray, $timeout );
2877                 if ( $numReadyPipes === false ) {
2878                         // @codingStandardsIgnoreEnd
2879                         $error = error_get_last();
2880                         if ( strncmp( $error['message'], $eintrMessage, strlen( $eintrMessage ) ) == 0 ) {
2881                                 continue;
2882                         } else {
2883                                 trigger_error( $error['message'], E_USER_WARNING );
2884                                 $logMsg = $error['message'];
2885                                 break;
2886                         }
2887                 }
2888                 foreach ( $readyPipes as $pipe ) {
2889                         $block = fread( $pipe, 65536 );
2890                         $fd = $fds[(int)$pipe];
2891                         if ( $block === '' ) {
2892                                 // End of file
2893                                 fclose( $pipes[$fd] );
2894                                 unset( $pipes[$fd] );
2895                                 if ( !$pipes ) {
2896                                         break 2;
2897                                 }
2898                         } elseif ( $block === false ) {
2899                                 // Read error
2900                                 $logMsg = "Error reading from pipe";
2901                                 break 2;
2902                         } elseif ( $fd == 1 ) {
2903                                 // From stdout
2904                                 $outBuffer .= $block;
2905                         } elseif ( $fd == 3 ) {
2906                                 // From log FD
2907                                 $logBuffer .= $block;
2908                                 if ( strpos( $block, "\n" ) !== false ) {
2909                                         $lines = explode( "\n", $logBuffer );
2910                                         $logBuffer = array_pop( $lines );
2911                                         foreach ( $lines as $line ) {
2912                                                 wfDebugLog( 'exec', $line );
2913                                         }
2914                                 }
2915                         }
2916                 }
2917         }
2918
2919         foreach ( $pipes as $pipe ) {
2920                 fclose( $pipe );
2921         }
2922
2923         // Use the status previously collected if possible, since proc_get_status()
2924         // just calls waitpid() which will not return anything useful the second time.
2925         if ( $running ) {
2926                 $status = proc_get_status( $proc );
2927         }
2928
2929         if ( $logMsg !== false ) {
2930                 // Read/select error
2931                 $retval = -1;
2932                 proc_close( $proc );
2933         } elseif ( $status['signaled'] ) {
2934                 $logMsg = "Exited with signal {$status['termsig']}";
2935                 $retval = 128 + $status['termsig'];
2936                 proc_close( $proc );
2937         } else {
2938                 if ( $status['running'] ) {
2939                         $retval = proc_close( $proc );
2940                 } else {
2941                         $retval = $status['exitcode'];
2942                         proc_close( $proc );
2943                 }
2944                 if ( $retval == 127 ) {
2945                         $logMsg = "Possibly missing executable file";
2946                 } elseif ( $retval >= 129 && $retval <= 192 ) {
2947                         $logMsg = "Probably exited with signal " . ( $retval - 128 );
2948                 }
2949         }
2950
2951         if ( $logMsg !== false ) {
2952                 wfDebugLog( 'exec', "$logMsg: $cmd" );
2953         }
2954
2955         return $outBuffer;
2956 }
2957
2958 /**
2959  * Execute a shell command, returning both stdout and stderr. Convenience
2960  * function, as all the arguments to wfShellExec can become unwieldy.
2961  *
2962  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2963  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2964  *   or an array of unescaped arguments, in which case each value will be escaped
2965  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2966  * @param null|mixed &$retval Optional, will receive the program's exit code.
2967  *   (non-zero is usually failure)
2968  * @param array $environ Optional environment variables which should be
2969  *   added to the executed command environment.
2970  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2971  *   this overwrites the global wgMaxShell* limits.
2972  * @return string Collected stdout and stderr as a string
2973  */
2974 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2975         return wfShellExec( $cmd, $retval, $environ, $limits,
2976                 array( 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ) );
2977 }
2978
2979 /**
2980  * Workaround for http://bugs.php.net/bug.php?id=45132
2981  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2982  */
2983 function wfInitShellLocale() {
2984         static $done = false;
2985         if ( $done ) {
2986                 return;
2987         }
2988         $done = true;
2989         global $wgShellLocale;
2990         if ( !wfIniGetBool( 'safe_mode' ) ) {
2991                 putenv( "LC_CTYPE=$wgShellLocale" );
2992                 setlocale( LC_CTYPE, $wgShellLocale );
2993         }
2994 }
2995
2996 /**
2997  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2998  * Note that $parameters should be a flat array and an option with an argument
2999  * should consist of two consecutive items in the array (do not use "--option value").
3000  *
3001  * @param string $script MediaWiki cli script path
3002  * @param array $parameters Arguments and options to the script
3003  * @param array $options Associative array of options:
3004  *              'php': The path to the php executable
3005  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
3006  * @return string
3007  */
3008 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
3009         global $wgPhpCli;
3010         // Give site config file a chance to run the script in a wrapper.
3011         // The caller may likely want to call wfBasename() on $script.
3012         Hooks::run( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
3013         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
3014         if ( isset( $options['wrapper'] ) ) {
3015                 $cmd[] = $options['wrapper'];
3016         }
3017         $cmd[] = $script;
3018         // Escape each parameter for shell
3019         return wfEscapeShellArg( array_merge( $cmd, $parameters ) );
3020 }
3021
3022 /**
3023  * wfMerge attempts to merge differences between three texts.
3024  * Returns true for a clean merge and false for failure or a conflict.
3025  *
3026  * @param string $old
3027  * @param string $mine
3028  * @param string $yours
3029  * @param string $result
3030  * @return bool
3031  */
3032 function wfMerge( $old, $mine, $yours, &$result ) {
3033         global $wgDiff3;
3034
3035         # This check may also protect against code injection in
3036         # case of broken installations.
3037         MediaWiki\suppressWarnings();
3038         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
3039         MediaWiki\restoreWarnings();
3040
3041         if ( !$haveDiff3 ) {
3042                 wfDebug( "diff3 not found\n" );
3043                 return false;
3044         }
3045
3046         # Make temporary files
3047         $td = wfTempDir();
3048         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3049         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
3050         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
3051
3052         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
3053         #       a newline character. To avoid this, we normalize the trailing whitespace before
3054         #       creating the diff.
3055
3056         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
3057         fclose( $oldtextFile );
3058         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
3059         fclose( $mytextFile );
3060         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
3061         fclose( $yourtextFile );
3062
3063         # Check for a conflict
3064         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '--overlap-only', $mytextName,
3065                 $oldtextName, $yourtextName );
3066         $handle = popen( $cmd, 'r' );
3067
3068         if ( fgets( $handle, 1024 ) ) {
3069                 $conflict = true;
3070         } else {
3071                 $conflict = false;
3072         }
3073         pclose( $handle );
3074
3075         # Merge differences
3076         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '-e', '--merge', $mytextName,
3077                 $oldtextName, $yourtextName );
3078         $handle = popen( $cmd, 'r' );
3079         $result = '';
3080         do {
3081                 $data = fread( $handle, 8192 );
3082                 if ( strlen( $data ) == 0 ) {
3083                         break;
3084                 }
3085                 $result .= $data;
3086         } while ( true );
3087         pclose( $handle );
3088         unlink( $mytextName );
3089         unlink( $oldtextName );
3090         unlink( $yourtextName );
3091
3092         if ( $result === '' && $old !== '' && !$conflict ) {
3093                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3094                 $conflict = true;
3095         }
3096         return !$conflict;
3097 }
3098
3099 /**
3100  * Returns unified plain-text diff of two texts.
3101  * "Useful" for machine processing of diffs.
3102  *
3103  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
3104  *
3105  * @param string $before The text before the changes.
3106  * @param string $after The text after the changes.
3107  * @param string $params Command-line options for the diff command.
3108  * @return string Unified diff of $before and $after
3109  */
3110 function wfDiff( $before, $after, $params = '-u' ) {
3111         if ( $before == $after ) {
3112                 return '';
3113         }
3114
3115         global $wgDiff;
3116         MediaWiki\suppressWarnings();
3117         $haveDiff = $wgDiff && file_exists( $wgDiff );
3118         MediaWiki\restoreWarnings();
3119
3120         # This check may also protect against code injection in
3121         # case of broken installations.
3122         if ( !$haveDiff ) {
3123                 wfDebug( "diff executable not found\n" );
3124                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3125                 $format = new UnifiedDiffFormatter();
3126                 return $format->format( $diffs );
3127         }
3128
3129         # Make temporary files
3130         $td = wfTempDir();
3131         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3132         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3133
3134         fwrite( $oldtextFile, $before );
3135         fclose( $oldtextFile );
3136         fwrite( $newtextFile, $after );
3137         fclose( $newtextFile );
3138
3139         // Get the diff of the two files
3140         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3141
3142         $h = popen( $cmd, 'r' );
3143         if ( !$h ) {
3144                 unlink( $oldtextName );
3145                 unlink( $newtextName );
3146                 throw new Exception( __METHOD__ . '(): popen() failed' );
3147         }
3148
3149         $diff = '';
3150
3151         do {
3152                 $data = fread( $h, 8192 );
3153                 if ( strlen( $data ) == 0 ) {
3154                         break;
3155                 }
3156                 $diff .= $data;
3157         } while ( true );
3158
3159         // Clean up
3160         pclose( $h );
3161         unlink( $oldtextName );
3162         unlink( $newtextName );
3163
3164         // Kill the --- and +++ lines. They're not useful.
3165         $diff_lines = explode( "\n", $diff );
3166         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
3167                 unset( $diff_lines[0] );
3168         }
3169         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
3170                 unset( $diff_lines[1] );
3171         }
3172
3173         $diff = implode( "\n", $diff_lines );
3174
3175         return $diff;
3176 }
3177
3178 /**
3179  * This function works like "use VERSION" in Perl, the program will die with a
3180  * backtrace if the current version of PHP is less than the version provided
3181  *
3182  * This is useful for extensions which due to their nature are not kept in sync
3183  * with releases, and might depend on other versions of PHP than the main code
3184  *
3185  * Note: PHP might die due to parsing errors in some cases before it ever
3186  *       manages to call this function, such is life
3187  *
3188  * @see perldoc -f use
3189  *
3190  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3191  * @throws MWException
3192  */
3193 function wfUsePHP( $req_ver ) {
3194         $php_ver = PHP_VERSION;
3195
3196         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3197                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3198         }
3199 }
3200
3201 /**
3202  * This function works like "use VERSION" in Perl except it checks the version
3203  * of MediaWiki, the program will die with a backtrace if the current version
3204  * of MediaWiki is less than the version provided.
3205  *
3206  * This is useful for extensions which due to their nature are not kept in sync
3207  * with releases
3208  *
3209  * Note: Due to the behavior of PHP's version_compare() which is used in this
3210  * function, if you want to allow the 'wmf' development versions add a 'c' (or
3211  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
3212  * targeted version number. For example if you wanted to allow any variation
3213  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
3214  * not result in the same comparison due to the internal logic of
3215  * version_compare().
3216  *
3217  * @see perldoc -f use
3218  *
3219  * @deprecated since 1.26, use the "requires' property of extension.json
3220  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3221  * @throws MWException
3222  */
3223 function wfUseMW( $req_ver ) {
3224         global $wgVersion;
3225
3226         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3227                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3228         }
3229 }
3230
3231 /**
3232  * Return the final portion of a pathname.
3233  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3234  * http://bugs.php.net/bug.php?id=33898
3235  *
3236  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3237  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3238  *
3239  * @param string $path
3240  * @param string $suffix String to remove if present
3241  * @return string
3242  */
3243 function wfBaseName( $path, $suffix = '' ) {
3244         if ( $suffix == '' ) {
3245                 $encSuffix = '';
3246         } else {
3247                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
3248         }
3249
3250         $matches = array();
3251         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3252                 return $matches[1];
3253         } else {
3254                 return '';
3255         }
3256 }
3257
3258 /**
3259  * Generate a relative path name to the given file.
3260  * May explode on non-matching case-insensitive paths,
3261  * funky symlinks, etc.
3262  *
3263  * @param string $path Absolute destination path including target filename
3264  * @param string $from Absolute source path, directory only
3265  * @return string
3266  */
3267 function wfRelativePath( $path, $from ) {
3268         // Normalize mixed input on Windows...
3269         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3270         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3271
3272         // Trim trailing slashes -- fix for drive root
3273         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3274         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3275
3276         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3277         $against = explode( DIRECTORY_SEPARATOR, $from );
3278
3279         if ( $pieces[0] !== $against[0] ) {
3280                 // Non-matching Windows drive letters?
3281                 // Return a full path.
3282                 return $path;
3283         }
3284
3285         // Trim off common prefix
3286         while ( count( $pieces ) && count( $against )
3287                 && $pieces[0] == $against[0] ) {
3288                 array_shift( $pieces );
3289                 array_shift( $against );
3290         }
3291
3292         // relative dots to bump us to the parent
3293         while ( count( $against ) ) {
3294                 array_unshift( $pieces, '..' );
3295                 array_shift( $against );
3296         }
3297
3298         array_push( $pieces, wfBaseName( $path ) );
3299
3300         return implode( DIRECTORY_SEPARATOR, $pieces );
3301 }
3302
3303 /**
3304  * Convert an arbitrarily-long digit string from one numeric base
3305  * to another, optionally zero-padding to a minimum column width.
3306  *
3307  * Supports base 2 through 36; digit values 10-36 are represented
3308  * as lowercase letters a-z. Input is case-insensitive.
3309  *
3310  * @param string $input Input number
3311  * @param int $sourceBase Base of the input number
3312  * @param int $destBase Desired base of the output
3313  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3314  * @param bool $lowercase Whether to output in lowercase or uppercase
3315  * @param string $engine Either "gmp", "bcmath", or "php"
3316  * @return string|bool The output number as a string, or false on error
3317  */
3318 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1,
3319         $lowercase = true, $engine = 'auto'
3320 ) {
3321         $input = (string)$input;
3322         if (
3323                 $sourceBase < 2 ||
3324                 $sourceBase > 36 ||
3325                 $destBase < 2 ||
3326                 $destBase > 36 ||
3327                 $sourceBase != (int)$sourceBase ||
3328                 $destBase != (int)$destBase ||
3329                 $pad != (int)$pad ||
3330                 !preg_match(
3331                         "/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i",
3332                         $input
3333                 )
3334         ) {
3335                 return false;
3336         }
3337
3338         static $baseChars = array(
3339                 10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
3340                 16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
3341                 22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
3342                 28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
3343                 34 => 'y', 35 => 'z',
3344
3345                 '0' => 0, '1' => 1, '2' => 2, '3' => 3, '4' => 4, '5' => 5,
3346                 '6' => 6, '7' => 7, '8' => 8, '9' => 9, 'a' => 10, 'b' => 11,
3347                 'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
3348                 'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
3349                 'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
3350                 'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
3351         );
3352
3353         if ( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
3354                 // Removing leading zeros works around broken base detection code in
3355                 // some PHP versions (see <https://bugs.php.net/bug.php?id=50175> and
3356                 // <https://bugs.php.net/bug.php?id=55398>).
3357                 $result = gmp_strval( gmp_init( ltrim( $input, '0' ) ?: '0', $sourceBase ), $destBase );
3358         } elseif ( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
3359                 $decimal = '0';
3360                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3361                         $decimal = bcmul( $decimal, $sourceBase );
3362                         $decimal = bcadd( $decimal, $baseChars[$char] );
3363                 }
3364
3365                 // @codingStandardsIgnoreStart Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
3366                 for ( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
3367                         $result .= $baseChars[bcmod( $decimal, $destBase )];
3368                 }
3369                 // @codingStandardsIgnoreEnd
3370
3371                 $result = strrev( $result );
3372         } else {
3373                 $inDigits = array();
3374                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3375                         $inDigits[] = $baseChars[$char];
3376                 }
3377
3378                 // Iterate over the input, modulo-ing out an output digit
3379                 // at a time until input is gone.
3380                 $result = '';
3381                 while ( $inDigits ) {
3382                         $work = 0;
3383                         $workDigits = array();
3384
3385                         // Long division...
3386                         foreach ( $inDigits as $digit ) {
3387                                 $work *= $sourceBase;
3388                                 $work += $digit;
3389
3390                                 if ( $workDigits || $work >= $destBase ) {
3391                                         $workDigits[] = (int)( $work / $destBase );
3392                                 }
3393                                 $work %= $destBase;
3394                         }
3395
3396                         // All that division leaves us with a remainder,
3397                         // which is conveniently our next output digit.
3398                         $result .= $baseChars[$work];
3399
3400                         // And we continue!
3401                         $inDigits = $workDigits;
3402                 }
3403
3404                 $result = strrev( $result );
3405         }
3406
3407         if ( !$lowercase ) {
3408                 $result = strtoupper( $result );
3409         }
3410
3411         return str_pad( $result, $pad, '0', STR_PAD_LEFT );
3412 }
3413
3414 /**
3415  * Check if there is sufficient entropy in php's built-in session generation
3416  *
3417  * @return bool True = there is sufficient entropy
3418  */
3419 function wfCheckEntropy() {
3420         return (
3421                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3422                         || ini_get( 'session.entropy_file' )
3423                 )
3424                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3425 }
3426
3427 /**
3428  * Override session_id before session startup if php's built-in
3429  * session generation code is not secure.
3430  */
3431 function wfFixSessionID() {
3432         // If the cookie or session id is already set we already have a session and should abort
3433         if ( isset( $_COOKIE[session_name()] ) || session_id() ) {
3434                 return;
3435         }
3436
3437         // PHP's built-in session entropy is enabled if:
3438         // - entropy_file is set or you're on Windows with php 5.3.3+
3439         // - AND entropy_length is > 0
3440         // We treat it as disabled if it doesn't have an entropy length of at least 32
3441         $entropyEnabled = wfCheckEntropy();
3442
3443         // If built-in entropy is not enabled or not sufficient override PHP's
3444         // built in session id generation code
3445         if ( !$entropyEnabled ) {
3446                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, " .
3447                         "overriding session id generation using our cryptrand source.\n" );
3448                 session_id( MWCryptRand::generateHex( 32 ) );
3449         }
3450 }
3451
3452 /**
3453  * Reset the session_id
3454  *
3455  * @since 1.22
3456  */
3457 function wfResetSessionID() {
3458         global $wgCookieSecure;
3459         $oldSessionId = session_id();
3460         $cookieParams = session_get_cookie_params();
3461         if ( wfCheckEntropy() && $wgCookieSecure == $cookieParams['secure'] ) {
3462                 session_regenerate_id( false );
3463         } else {
3464                 $tmp = $_SESSION;
3465                 session_destroy();
3466                 wfSetupSession( MWCryptRand::generateHex( 32 ) );
3467                 $_SESSION = $tmp;
3468         }
3469         $newSessionId = session_id();
3470 }
3471
3472 /**
3473  * Initialise php session
3474  *
3475  * @param bool $sessionId
3476  */
3477 function wfSetupSession( $sessionId = false ) {
3478         global $wgSessionsInObjectCache, $wgSessionHandler;
3479         global $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
3480
3481         if ( $wgSessionsInObjectCache ) {
3482                 ObjectCacheSessionHandler::install();
3483         } elseif ( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3484                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3485                 # hasn't already been set to the desired value (that causes errors)
3486                 ini_set( 'session.save_handler', $wgSessionHandler );
3487         }
3488
3489         session_set_cookie_params(
3490                 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
3491         session_cache_limiter( 'private, must-revalidate' );
3492         if ( $sessionId ) {
3493                 session_id( $sessionId );
3494         } else {
3495                 wfFixSessionID();
3496         }
3497
3498         MediaWiki\suppressWarnings();
3499         session_start();
3500         MediaWiki\restoreWarnings();
3501
3502         if ( $wgSessionsInObjectCache ) {
3503                 ObjectCacheSessionHandler::renewCurrentSession();
3504         }
3505 }
3506
3507 /**
3508  * Get an object from the precompiled serialized directory
3509  *
3510  * @param string $name
3511  * @return mixed The variable on success, false on failure
3512  */
3513 function wfGetPrecompiledData( $name ) {
3514         global $IP;
3515
3516         $file = "$IP/serialized/$name";
3517         if ( file_exists( $file ) ) {
3518                 $blob = file_get_contents( $file );
3519                 if ( $blob ) {
3520                         return unserialize( $blob );
3521                 }
3522         }
3523         return false;
3524 }
3525
3526 /**
3527  * Make a cache key for the local wiki.
3528  *
3529  * @param string $args,...
3530  * @return string
3531  */
3532 function wfMemcKey( /*...*/ ) {
3533         global $wgCachePrefix;
3534         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3535         $args = func_get_args();
3536         $key = $prefix . ':' . implode( ':', $args );
3537         return strtr( $key, ' ', '_' );
3538 }
3539
3540 /**
3541  * Make a cache key for a foreign DB.
3542  *
3543  * Must match what wfMemcKey() would produce in context of the foreign wiki.
3544  *
3545  * @param string $db
3546  * @param string $prefix
3547  * @param string $args,...
3548  * @return string
3549  */
3550 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
3551         $args = array_slice( func_get_args(), 2 );
3552         if ( $prefix ) {
3553                 // Match wfWikiID() logic
3554                 $key = "$db-$prefix:" . implode( ':', $args );
3555         } else {
3556                 $key = $db . ':' . implode( ':', $args );
3557         }
3558         return strtr( $key, ' ', '_' );
3559 }
3560
3561 /**
3562  * Make a cache key with database-agnostic prefix.
3563  *
3564  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
3565  * instead. Must have a prefix as otherwise keys that use a database name
3566  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
3567  *
3568  * @since 1.26
3569  * @param string $args,...
3570  * @return string
3571  */
3572 function wfGlobalCacheKey( /*...*/ ) {
3573         $args = func_get_args();
3574         $key = 'global:' . implode( ':', $args );
3575         return strtr( $key, ' ', '_' );
3576 }
3577
3578 /**
3579  * Get an ASCII string identifying this wiki
3580  * This is used as a prefix in memcached keys
3581  *
3582  * @return string
3583  */
3584 function wfWikiID() {
3585         global $wgDBprefix, $wgDBname;
3586         if ( $wgDBprefix ) {
3587                 return "$wgDBname-$wgDBprefix";
3588         } else {
3589                 return $wgDBname;
3590         }
3591 }
3592
3593 /**
3594  * Split a wiki ID into DB name and table prefix
3595  *
3596  * @param string $wiki
3597  *
3598  * @return array
3599  */
3600 function wfSplitWikiID( $wiki ) {
3601         $bits = explode( '-', $wiki, 2 );
3602         if ( count( $bits ) < 2 ) {
3603                 $bits[] = '';
3604         }
3605         return $bits;
3606 }
3607
3608 /**
3609  * Get a Database object.
3610  *
3611  * @param int $db Index of the connection to get. May be DB_MASTER for the
3612  *            master (for write queries), DB_SLAVE for potentially lagged read
3613  *            queries, or an integer >= 0 for a particular server.
3614  *
3615  * @param string|string[] $groups Query groups. An array of group names that this query
3616  *                belongs to. May contain a single string if the query is only
3617  *                in one group.
3618  *
3619  * @param string|bool $wiki The wiki ID, or false for the current wiki
3620  *
3621  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3622  * will always return the same object, unless the underlying connection or load
3623  * balancer is manually destroyed.
3624  *
3625  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3626  * updater to ensure that a proper database is being updated.
3627  *
3628  * @return DatabaseBase
3629  */
3630 function wfGetDB( $db, $groups = array(), $wiki = false ) {
3631         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3632 }
3633
3634 /**
3635  * Get a load balancer object.
3636  *
3637  * @param string|bool $wiki Wiki ID, or false for the current wiki
3638  * @return LoadBalancer
3639  */
3640 function wfGetLB( $wiki = false ) {
3641         return wfGetLBFactory()->getMainLB( $wiki );
3642 }
3643
3644 /**
3645  * Get the load balancer factory object
3646  *
3647  * @return LBFactory
3648  */
3649 function wfGetLBFactory() {
3650         return LBFactory::singleton();
3651 }
3652
3653 /**
3654  * Find a file.
3655  * Shortcut for RepoGroup::singleton()->findFile()
3656  *
3657  * @param string $title String or Title object
3658  * @param array $options Associative array of options (see RepoGroup::findFile)
3659  * @return File|bool File, or false if the file does not exist
3660  */
3661 function wfFindFile( $title, $options = array() ) {
3662         return RepoGroup::singleton()->findFile( $title, $options );
3663 }
3664
3665 /**
3666  * Get an object referring to a locally registered file.
3667  * Returns a valid placeholder object if the file does not exist.
3668  *
3669  * @param Title|string $title
3670  * @return LocalFile|null A File, or null if passed an invalid Title
3671  */
3672 function wfLocalFile( $title ) {
3673         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3674 }
3675
3676 /**
3677  * Should low-performance queries be disabled?
3678  *
3679  * @return bool
3680  * @codeCoverageIgnore
3681  */
3682 function wfQueriesMustScale() {
3683         global $wgMiserMode;
3684         return $wgMiserMode
3685                 || ( SiteStats::pages() > 100000
3686                 && SiteStats::edits() > 1000000
3687                 && SiteStats::users() > 10000 );
3688 }
3689
3690 /**
3691  * Get the path to a specified script file, respecting file
3692  * extensions; this is a wrapper around $wgScriptExtension etc.
3693  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3694  *
3695  * @param string $script Script filename, sans extension
3696  * @return string
3697  */
3698 function wfScript( $script = 'index' ) {
3699         global $wgScriptPath, $wgScriptExtension, $wgScript, $wgLoadScript;
3700         if ( $script === 'index' ) {
3701                 return $wgScript;
3702         } elseif ( $script === 'load' ) {
3703                 return $wgLoadScript;
3704         } else {
3705                 return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3706         }
3707 }
3708
3709 /**
3710  * Get the script URL.
3711  *
3712  * @return string Script URL
3713  */
3714 function wfGetScriptUrl() {
3715         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3716                 #
3717                 # as it was called, minus the query string.
3718                 #
3719                 # Some sites use Apache rewrite rules to handle subdomains,
3720                 # and have PHP set up in a weird way that causes PHP_SELF
3721                 # to contain the rewritten URL instead of the one that the
3722                 # outside world sees.
3723                 #
3724                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3725                 # provides containing the "before" URL.
3726                 return $_SERVER['SCRIPT_NAME'];
3727         } else {
3728                 return $_SERVER['URL'];
3729         }
3730 }
3731
3732 /**
3733  * Convenience function converts boolean values into "true"
3734  * or "false" (string) values
3735  *
3736  * @param bool $value
3737  * @return string
3738  */
3739 function wfBoolToStr( $value ) {
3740         return $value ? 'true' : 'false';
3741 }
3742
3743 /**
3744  * Get a platform-independent path to the null file, e.g. /dev/null
3745  *
3746  * @return string
3747  */
3748 function wfGetNull() {
3749         return wfIsWindows() ? 'NUL' : '/dev/null';
3750 }
3751
3752 /**
3753  * Waits for the slaves to catch up to the master position
3754  *
3755  * Use this when updating very large numbers of rows, as in maintenance scripts,
3756  * to avoid causing too much lag. Of course, this is a no-op if there are no slaves.
3757  *
3758  * By default this waits on the main DB cluster of the current wiki.
3759  * If $cluster is set to "*" it will wait on all DB clusters, including
3760  * external ones. If the lag being waiting on is caused by the code that
3761  * does this check, it makes since to use $ifWritesSince, particularly if
3762  * cluster is "*", to avoid excess overhead.
3763  *
3764  * Never call this function after a big DB write that is still in a transaction.
3765  * This only makes sense after the possible lag inducing changes were committed.
3766  *
3767  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
3768  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
3769  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
3770  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
3771  * @return bool Success (able to connect and no timeouts reached)
3772  */
3773 function wfWaitForSlaves(
3774         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3775 ) {
3776         // B/C: first argument used to be "max seconds of lag"; ignore such values
3777         $ifWritesSince = ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null;
3778
3779         if ( $timeout === null ) {
3780                 $timeout = ( PHP_SAPI === 'cli' ) ? 86400 : 10;
3781         }
3782
3783         // Figure out which clusters need to be checked
3784         /** @var LoadBalancer[] $lbs */
3785         $lbs = array();
3786         if ( $cluster === '*' ) {
3787                 wfGetLBFactory()->forEachLB( function ( LoadBalancer $lb ) use ( &$lbs ) {
3788                         $lbs[] = $lb;
3789                 } );
3790         } elseif ( $cluster !== false ) {
3791                 $lbs[] = wfGetLBFactory()->getExternalLB( $cluster );
3792         } else {
3793                 $lbs[] = wfGetLB( $wiki );
3794         }
3795
3796         // Get all the master positions of applicable DBs right now.
3797         // This can be faster since waiting on one cluster reduces the
3798         // time needed to wait on the next clusters.
3799         $masterPositions = array_fill( 0, count( $lbs ), false );
3800         foreach ( $lbs as $i => $lb ) {
3801                 if ( $lb->getServerCount() <= 1 ) {
3802                         // Bug 27975 - Don't try to wait for slaves if there are none
3803                         // Prevents permission error when getting master position
3804                         continue;
3805                 } elseif ( $ifWritesSince && $lb->lastMasterChangeTimestamp() < $ifWritesSince ) {
3806                         continue; // no writes since the last wait
3807                 }
3808                 $masterPositions[$i] = $lb->getMasterPos();
3809         }
3810
3811         $ok = true;
3812         foreach ( $lbs as $i => $lb ) {
3813                 if ( $masterPositions[$i] ) {
3814                         // The DBMS may not support getMasterPos() or the whole
3815                         // load balancer might be fake (e.g. $wgAllDBsAreLocalhost).
3816                         $ok = $lb->waitForAll( $masterPositions[$i], $timeout ) && $ok;
3817                 }
3818         }
3819
3820         return $ok;
3821 }
3822
3823 /**
3824  * Count down from $seconds to zero on the terminal, with a one-second pause
3825  * between showing each number. For use in command-line scripts.
3826  *
3827  * @codeCoverageIgnore
3828  * @param int $seconds
3829  */
3830 function wfCountDown( $seconds ) {
3831         for ( $i = $seconds; $i >= 0; $i-- ) {
3832                 if ( $i != $seconds ) {
3833                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3834                 }
3835                 echo $i;
3836                 flush();
3837                 if ( $i ) {
3838                         sleep( 1 );
3839                 }
3840         }
3841         echo "\n";
3842 }
3843
3844 /**
3845  * Replace all invalid characters with -
3846  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3847  * By default, $wgIllegalFileChars = ':'
3848  *
3849  * @param string $name Filename to process
3850  * @return string
3851  */
3852 function wfStripIllegalFilenameChars( $name ) {
3853         global $wgIllegalFileChars;
3854         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3855         $name = wfBaseName( $name );
3856         $name = preg_replace(
3857                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3858                 '-',
3859                 $name
3860         );
3861         return $name;
3862 }
3863
3864 /**
3865  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3866  *
3867  * @return int Resulting value of the memory limit.
3868  */
3869 function wfMemoryLimit() {
3870         global $wgMemoryLimit;
3871         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3872         if ( $memlimit != -1 ) {
3873                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3874                 if ( $conflimit == -1 ) {
3875                         wfDebug( "Removing PHP's memory limit\n" );
3876                         MediaWiki\suppressWarnings();
3877                         ini_set( 'memory_limit', $conflimit );
3878                         MediaWiki\restoreWarnings();
3879                         return $conflimit;
3880                 } elseif ( $conflimit > $memlimit ) {
3881                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3882                         MediaWiki\suppressWarnings();
3883                         ini_set( 'memory_limit', $conflimit );
3884                         MediaWiki\restoreWarnings();
3885                         return $conflimit;
3886                 }
3887         }
3888         return $memlimit;
3889 }
3890
3891 /**
3892  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3893  *
3894  * @return int Prior time limit
3895  * @since 1.26
3896  */
3897 function wfTransactionalTimeLimit() {
3898         global $wgTransactionalTimeLimit;
3899
3900         $timeLimit = ini_get( 'max_execution_time' );
3901         // Note that CLI scripts use 0
3902         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3903                 set_time_limit( $wgTransactionalTimeLimit );
3904         }
3905
3906         ignore_user_abort( true ); // ignore client disconnects
3907
3908         return $timeLimit;
3909 }
3910
3911 /**
3912  * Converts shorthand byte notation to integer form
3913  *
3914  * @param string $string
3915  * @return int
3916  */
3917 function wfShorthandToInteger( $string = '' ) {
3918         $string = trim( $string );
3919         if ( $string === '' ) {
3920                 return -1;
3921         }
3922         $last = $string[strlen( $string ) - 1];
3923         $val = intval( $string );
3924         switch ( $last ) {
3925                 case 'g':
3926                 case 'G':
3927                         $val *= 1024;
3928                         // break intentionally missing
3929                 case 'm':
3930                 case 'M':
3931                         $val *= 1024;
3932                         // break intentionally missing
3933                 case 'k':
3934                 case 'K':
3935                         $val *= 1024;
3936         }
3937
3938         return $val;
3939 }
3940
3941 /**
3942  * Get the normalised IETF language tag
3943  * See unit test for examples.
3944  *
3945  * @param string $code The language code.
3946  * @return string The language code which complying with BCP 47 standards.
3947  */
3948 function wfBCP47( $code ) {
3949         $codeSegment = explode( '-', $code );
3950         $codeBCP = array();
3951         foreach ( $codeSegment as $segNo => $seg ) {
3952                 // when previous segment is x, it is a private segment and should be lc
3953                 if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3954                         $codeBCP[$segNo] = strtolower( $seg );
3955                 // ISO 3166 country code
3956                 } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3957                         $codeBCP[$segNo] = strtoupper( $seg );
3958                 // ISO 15924 script code
3959                 } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3960                         $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3961                 // Use lowercase for other cases
3962                 } else {
3963                         $codeBCP[$segNo] = strtolower( $seg );
3964                 }
3965         }
3966         $langCode = implode( '-', $codeBCP );
3967         return $langCode;
3968 }
3969
3970 /**
3971  * Get a specific cache object.
3972  *
3973  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3974  * @return BagOStuff
3975  */
3976 function wfGetCache( $cacheType ) {
3977         return ObjectCache::getInstance( $cacheType );
3978 }
3979
3980 /**
3981  * Get the main cache object
3982  *
3983  * @return BagOStuff
3984  */
3985 function wfGetMainCache() {
3986         global $wgMainCacheType;
3987         return ObjectCache::getInstance( $wgMainCacheType );
3988 }
3989
3990 /**
3991  * Get the cache object used by the message cache
3992  *
3993  * @return BagOStuff
3994  */
3995 function wfGetMessageCacheStorage() {
3996         global $wgMessageCacheType;
3997         return ObjectCache::getInstance( $wgMessageCacheType );
3998 }
3999
4000 /**
4001  * Get the cache object used by the parser cache
4002  *
4003  * @return BagOStuff
4004  */
4005 function wfGetParserCacheStorage() {
4006         global $wgParserCacheType;
4007         return ObjectCache::getInstance( $wgParserCacheType );
4008 }
4009
4010 /**
4011  * Call hook functions defined in $wgHooks
4012  *
4013  * @param string $event Event name
4014  * @param array $args Parameters passed to hook functions
4015  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
4016  *
4017  * @return bool True if no handler aborted the hook
4018  * @deprecated 1.25 - use Hooks::run
4019  */
4020 function wfRunHooks( $event, array $args = array(), $deprecatedVersion = null ) {
4021         return Hooks::run( $event, $args, $deprecatedVersion );
4022 }
4023
4024 /**
4025  * Wrapper around php's unpack.
4026  *
4027  * @param string $format The format string (See php's docs)
4028  * @param string $data A binary string of binary data
4029  * @param int|bool $length The minimum length of $data or false. This is to
4030  *      prevent reading beyond the end of $data. false to disable the check.
4031  *
4032  * Also be careful when using this function to read unsigned 32 bit integer
4033  * because php might make it negative.
4034  *
4035  * @throws MWException If $data not long enough, or if unpack fails
4036  * @return array Associative array of the extracted data
4037  */
4038 function wfUnpack( $format, $data, $length = false ) {
4039         if ( $length !== false ) {
4040                 $realLen = strlen( $data );
4041                 if ( $realLen < $length ) {
4042                         throw new MWException( "Tried to use wfUnpack on a "
4043                                 . "string of length $realLen, but needed one "
4044                                 . "of at least length $length."
4045                         );
4046                 }
4047         }
4048
4049         MediaWiki\suppressWarnings();
4050         $result = unpack( $format, $data );
4051         MediaWiki\restoreWarnings();
4052
4053         if ( $result === false ) {
4054                 // If it cannot extract the packed data.
4055                 throw new MWException( "unpack could not unpack binary data" );
4056         }
4057         return $result;
4058 }
4059
4060 /**
4061  * Determine if an image exists on the 'bad image list'.
4062  *
4063  * The format of MediaWiki:Bad_image_list is as follows:
4064  *    * Only list items (lines starting with "*") are considered
4065  *    * The first link on a line must be a link to a bad image
4066  *    * Any subsequent links on the same line are considered to be exceptions,
4067  *      i.e. articles where the image may occur inline.
4068  *
4069  * @param string $name The image name to check
4070  * @param Title|bool $contextTitle The page on which the image occurs, if known
4071  * @param string $blacklist Wikitext of a file blacklist
4072  * @return bool
4073  */
4074 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
4075         # Handle redirects
4076         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
4077         if ( $redirectTitle ) {
4078                 $name = $redirectTitle->getDBkey();
4079         }
4080
4081         # Run the extension hook
4082         $bad = false;
4083         if ( !Hooks::run( 'BadImage', array( $name, &$bad ) ) ) {
4084                 return $bad;
4085         }
4086
4087         $cache = ObjectCache::newAccelerator( 'hash' );
4088         $key = wfMemcKey( 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist ) );
4089         $badImages = $cache->get( $key );
4090
4091         if ( $badImages === false ) { // cache miss
4092                 if ( $blacklist === null ) {
4093                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
4094                 }
4095                 # Build the list now
4096                 $badImages = array();
4097                 $lines = explode( "\n", $blacklist );
4098                 foreach ( $lines as $line ) {
4099                         # List items only
4100                         if ( substr( $line, 0, 1 ) !== '*' ) {
4101                                 continue;
4102                         }
4103
4104                         # Find all links
4105                         $m = array();
4106                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
4107                                 continue;
4108                         }
4109
4110                         $exceptions = array();
4111                         $imageDBkey = false;
4112                         foreach ( $m[1] as $i => $titleText ) {
4113                                 $title = Title::newFromText( $titleText );
4114                                 if ( !is_null( $title ) ) {
4115                                         if ( $i == 0 ) {
4116                                                 $imageDBkey = $title->getDBkey();
4117                                         } else {
4118                                                 $exceptions[$title->getPrefixedDBkey()] = true;
4119                                         }
4120                                 }
4121                         }
4122
4123                         if ( $imageDBkey !== false ) {
4124                                 $badImages[$imageDBkey] = $exceptions;
4125                         }
4126                 }
4127                 $cache->set( $key, $badImages, 60 );
4128         }
4129
4130         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4131         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4132
4133         return $bad;
4134 }
4135
4136 /**
4137  * Determine whether the client at a given source IP is likely to be able to
4138  * access the wiki via HTTPS.
4139  *
4140  * @param string $ip The IPv4/6 address in the normal human-readable form
4141  * @return bool
4142  */
4143 function wfCanIPUseHTTPS( $ip ) {
4144         $canDo = true;
4145         Hooks::run( 'CanIPUseHTTPS', array( $ip, &$canDo ) );
4146         return !!$canDo;
4147 }
4148
4149 /**
4150  * Determine input string is represents as infinity
4151  *
4152  * @param string $str The string to determine
4153  * @return bool
4154  * @since 1.25
4155  */
4156 function wfIsInfinity( $str ) {
4157         $infinityValues = array( 'infinite', 'indefinite', 'infinity', 'never' );
4158         return in_array( $str, $infinityValues );
4159 }
4160
4161 /**
4162  * Work out the IP address based on various globals
4163  * For trusted proxies, use the XFF client IP (first of the chain)
4164  *
4165  * @deprecated since 1.19; call $wgRequest->getIP() directly.
4166  * @return string
4167  */
4168 function wfGetIP() {
4169         wfDeprecated( __METHOD__, '1.19' );
4170         global $wgRequest;
4171         return $wgRequest->getIP();
4172 }
4173
4174 /**
4175  * Checks if an IP is a trusted proxy provider.
4176  * Useful to tell if X-Forwarded-For data is possibly bogus.
4177  * Squid cache servers for the site are whitelisted.
4178  * @deprecated Since 1.24, use IP::isTrustedProxy()
4179  *
4180  * @param string $ip
4181  * @return bool
4182  */
4183 function wfIsTrustedProxy( $ip ) {
4184         wfDeprecated( __METHOD__, '1.24' );
4185         return IP::isTrustedProxy( $ip );
4186 }
4187
4188 /**
4189  * Checks if an IP matches a proxy we've configured.
4190  * @deprecated Since 1.24, use IP::isConfiguredProxy()
4191  *
4192  * @param string $ip
4193  * @return bool
4194  * @since 1.23 Supports CIDR ranges in $wgSquidServersNoPurge
4195  */
4196 function wfIsConfiguredProxy( $ip ) {
4197         wfDeprecated( __METHOD__, '1.24' );
4198         return IP::isConfiguredProxy( $ip );
4199 }
4200
4201 /**
4202  * Returns true if these thumbnail parameters match one that MediaWiki
4203  * requests from file description pages and/or parser output.
4204  *
4205  * $params is considered non-standard if they involve a non-standard
4206  * width or any non-default parameters aside from width and page number.
4207  * The number of possible files with standard parameters is far less than
4208  * that of all combinations; rate-limiting for them can thus be more generious.
4209  *
4210  * @param File $file
4211  * @param array $params
4212  * @return bool
4213  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
4214  */
4215 function wfThumbIsStandard( File $file, array $params ) {
4216         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
4217
4218         $multipliers = array( 1 );
4219         if ( $wgResponsiveImages ) {
4220                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
4221                 // @see Linker::processResponsiveImages
4222                 $multipliers[] = 1.5;
4223                 $multipliers[] = 2;
4224         }
4225
4226         $handler = $file->getHandler();
4227         if ( !$handler || !isset( $params['width'] ) ) {
4228                 return false;
4229         }
4230
4231         $basicParams = array();
4232         if ( isset( $params['page'] ) ) {
4233                 $basicParams['page'] = $params['page'];
4234         }
4235
4236         $thumbLimits = array();
4237         $imageLimits = array();
4238         // Expand limits to account for multipliers
4239         foreach ( $multipliers as $multiplier ) {
4240                 $thumbLimits = array_merge( $thumbLimits, array_map(
4241                         function ( $width ) use ( $multiplier ) {
4242                                 return round( $width * $multiplier );
4243                         }, $wgThumbLimits )
4244                 );
4245                 $imageLimits = array_merge( $imageLimits, array_map(
4246                         function ( $pair ) use ( $multiplier ) {
4247                                 return array(
4248                                         round( $pair[0] * $multiplier ),
4249                                         round( $pair[1] * $multiplier ),
4250                                 );
4251                         }, $wgImageLimits )
4252                 );
4253         }
4254
4255         // Check if the width matches one of $wgThumbLimits
4256         if ( in_array( $params['width'], $thumbLimits ) ) {
4257                 $normalParams = $basicParams + array( 'width' => $params['width'] );
4258                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
4259                 $handler->normaliseParams( $file, $normalParams );
4260         } else {
4261                 // If not, then check if the width matchs one of $wgImageLimits
4262                 $match = false;
4263                 foreach ( $imageLimits as $pair ) {
4264                         $normalParams = $basicParams + array( 'width' => $pair[0], 'height' => $pair[1] );
4265                         // Decide whether the thumbnail should be scaled on width or height.
4266                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
4267                         $handler->normaliseParams( $file, $normalParams );
4268                         // Check if this standard thumbnail size maps to the given width
4269                         if ( $normalParams['width'] == $params['width'] ) {
4270                                 $match = true;
4271                                 break;
4272                         }
4273                 }
4274                 if ( !$match ) {
4275                         return false; // not standard for description pages
4276                 }
4277         }
4278
4279         // Check that the given values for non-page, non-width, params are just defaults
4280         foreach ( $params as $key => $value ) {
4281                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
4282                         return false;
4283                 }
4284         }
4285
4286         return true;
4287 }
4288
4289 /**
4290  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
4291  *
4292  * Values that exist in both values will be combined with += (all values of the array
4293  * of $newValues will be added to the values of the array of $baseArray, while values,
4294  * that exists in both, the value of $baseArray will be used).
4295  *
4296  * @param array $baseArray The array where you want to add the values of $newValues to
4297  * @param array $newValues An array with new values
4298  * @return array The combined array
4299  * @since 1.26
4300  */
4301 function wfArrayPlus2d( array $baseArray, array $newValues ) {
4302         // First merge items that are in both arrays
4303         foreach ( $baseArray as $name => &$groupVal ) {
4304                 if ( isset( $newValues[$name] ) ) {
4305                         $groupVal += $newValues[$name];
4306                 }
4307         }
4308         // Now add items that didn't exist yet
4309         $baseArray += $newValues;
4310
4311         return $baseArray;
4312 }