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 use MediaWiki\ProcOpenError;
  30 use MediaWiki\Session\SessionManager;
  31 use MediaWiki\MediaWikiServices;
  32 use MediaWiki\Shell\Shell;
  33 use Wikimedia\ScopedCallback;
  34 use Wikimedia\Rdbms\DBReplicationWaitError;
  35
  36 // Hide compatibility functions from Doxygen
  37 /// @cond
  38 /**
  39  * Compatibility functions
  40  *
  41  * We support PHP 5.5.9 and up.
  42  * Re-implementations of newer functions or functions in non-standard
  43  * PHP extensions may be included here.
  44  */
  45
  46 // hash_equals function only exists in PHP >= 5.6.0
  47 // https://secure.php.net/hash_equals
  48 if ( !function_exists( 'hash_equals' ) ) {
  49         /**
  50          * Check whether a user-provided string is equal to a fixed-length secret string
  51          * without revealing bytes of the secret string through timing differences.
  52          *
  53          * The usual way to compare strings (PHP's === operator or the underlying memcmp()
  54          * function in C) is to compare corresponding bytes and stop at the first difference,
  55          * which would take longer for a partial match than for a complete mismatch. This
  56          * is not secure when one of the strings (e.g. an HMAC or token) must remain secret
  57          * and the other may come from an attacker. Statistical analysis of timing measurements
  58          * over many requests may allow the attacker to guess the string's bytes one at a time
  59          * (and check his guesses) even if the timing differences are extremely small.
  60          *
  61          * When making such a security-sensitive comparison, it is essential that the sequence
  62          * in which instructions are executed and memory locations are accessed not depend on
  63          * the secret string's value. HOWEVER, for simplicity, we do not attempt to minimize
  64          * the inevitable leakage of the string's length. That is generally known anyway as
  65          * a chararacteristic of the hash function used to compute the secret value.
  66          *
  67          * Longer explanation: http://www.emerose.com/timing-attacks-explained
  68          *
  69          * @codeCoverageIgnore
  70          * @param string $known_string Fixed-length secret string to compare against
  71          * @param string $user_string User-provided string
  72          * @return bool True if the strings are the same, false otherwise
  73          */
  74         function hash_equals( $known_string, $user_string ) {
  75                 // Strict type checking as in PHP's native implementation
  76                 if ( !is_string( $known_string ) ) {
  77                         trigger_error( 'hash_equals(): Expected known_string to be a string, ' .
  78                                 gettype( $known_string ) . ' given', E_USER_WARNING );
  79
  80                         return false;
  81                 }
  82
  83                 if ( !is_string( $user_string ) ) {
  84                         trigger_error( 'hash_equals(): Expected user_string to be a string, ' .
  85                                 gettype( $user_string ) . ' given', E_USER_WARNING );
  86
  87                         return false;
  88                 }
  89
  90                 $known_string_len = strlen( $known_string );
  91                 if ( $known_string_len !== strlen( $user_string ) ) {
  92                         return false;
  93                 }
  94
  95                 $result = 0;
  96                 for ( $i = 0; $i < $known_string_len; $i++ ) {
  97                         $result |= ord( $known_string[$i] ) ^ ord( $user_string[$i] );
  98                 }
  99
 100                 return ( $result === 0 );
 101         }
 102 }
 103 /// @endcond
 104
 105 /**
 106  * Load an extension
 107  *
 108  * This queues an extension to be loaded through
 109  * the ExtensionRegistry system.
 110  *
 111  * @param string $ext Name of the extension to load
 112  * @param string|null $path Absolute path of where to find the extension.json file
 113  * @since 1.25
 114  */
 115 function wfLoadExtension( $ext, $path = null ) {
 116         if ( !$path ) {
 117                 global $wgExtensionDirectory;
 118                 $path = "$wgExtensionDirectory/$ext/extension.json";
 119         }
 120         ExtensionRegistry::getInstance()->queue( $path );
 121 }
 122
 123 /**
 124  * Load multiple extensions at once
 125  *
 126  * Same as wfLoadExtension, but more efficient if you
 127  * are loading multiple extensions.
 128  *
 129  * If you want to specify custom paths, you should interact with
 130  * ExtensionRegistry directly.
 131  *
 132  * @see wfLoadExtension
 133  * @param string[] $exts Array of extension names to load
 134  * @since 1.25
 135  */
 136 function wfLoadExtensions( array $exts ) {
 137         global $wgExtensionDirectory;
 138         $registry = ExtensionRegistry::getInstance();
 139         foreach ( $exts as $ext ) {
 140                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
 141         }
 142 }
 143
 144 /**
 145  * Load a skin
 146  *
 147  * @see wfLoadExtension
 148  * @param string $skin Name of the extension to load
 149  * @param string|null $path Absolute path of where to find the skin.json file
 150  * @since 1.25
 151  */
 152 function wfLoadSkin( $skin, $path = null ) {
 153         if ( !$path ) {
 154                 global $wgStyleDirectory;
 155                 $path = "$wgStyleDirectory/$skin/skin.json";
 156         }
 157         ExtensionRegistry::getInstance()->queue( $path );
 158 }
 159
 160 /**
 161  * Load multiple skins at once
 162  *
 163  * @see wfLoadExtensions
 164  * @param string[] $skins Array of extension names to load
 165  * @since 1.25
 166  */
 167 function wfLoadSkins( array $skins ) {
 168         global $wgStyleDirectory;
 169         $registry = ExtensionRegistry::getInstance();
 170         foreach ( $skins as $skin ) {
 171                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 172         }
 173 }
 174
 175 /**
 176  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 177  * @param array $a
 178  * @param array $b
 179  * @return array
 180  */
 181 function wfArrayDiff2( $a, $b ) {
 182         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 183 }
 184
 185 /**
 186  * @param array|string $a
 187  * @param array|string $b
 188  * @return int
 189  */
 190 function wfArrayDiff2_cmp( $a, $b ) {
 191         if ( is_string( $a ) && is_string( $b ) ) {
 192                 return strcmp( $a, $b );
 193         } elseif ( count( $a ) !== count( $b ) ) {
 194                 return count( $a ) < count( $b ) ? -1 : 1;
 195         } else {
 196                 reset( $a );
 197                 reset( $b );
 198                 while ( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 199                         $cmp = strcmp( $valueA, $valueB );
 200                         if ( $cmp !== 0 ) {
 201                                 return $cmp;
 202                         }
 203                 }
 204                 return 0;
 205         }
 206 }
 207
 208 /**
 209  * Like array_filter with ARRAY_FILTER_USE_BOTH, but works pre-5.6.
 210  *
 211  * @param array $arr
 212  * @param callable $callback Will be called with the array value and key (in that order) and
 213  *   should return a bool which will determine whether the array element is kept.
 214  * @return array
 215  */
 216 function wfArrayFilter( array $arr, callable $callback ) {
 217         if ( defined( 'ARRAY_FILTER_USE_BOTH' ) ) {
 218                 return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 219         }
 220         $filteredKeys = array_filter( array_keys( $arr ), function ( $key ) use ( $arr, $callback ) {
 221                 return call_user_func( $callback, $arr[$key], $key );
 222         } );
 223         return array_intersect_key( $arr, array_fill_keys( $filteredKeys, true ) );
 224 }
 225
 226 /**
 227  * Like array_filter with ARRAY_FILTER_USE_KEY, but works pre-5.6.
 228  *
 229  * @param array $arr
 230  * @param callable $callback Will be called with the array key and should return a bool which
 231  *   will determine whether the array element is kept.
 232  * @return array
 233  */
 234 function wfArrayFilterByKey( array $arr, callable $callback ) {
 235         return wfArrayFilter( $arr, function ( $val, $key ) use ( $callback ) {
 236                 return call_user_func( $callback, $key );
 237         } );
 238 }
 239
 240 /**
 241  * Appends to second array if $value differs from that in $default
 242  *
 243  * @param string|int $key
 244  * @param mixed $value
 245  * @param mixed $default
 246  * @param array &$changed Array to alter
 247  * @throws MWException
 248  */
 249 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 250         if ( is_null( $changed ) ) {
 251                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 252         }
 253         if ( $default[$key] !== $value ) {
 254                 $changed[$key] = $value;
 255         }
 256 }
 257
 258 /**
 259  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 260  * e.g.
 261  *     wfMergeErrorArrays(
 262  *       [ [ 'x' ] ],
 263  *       [ [ 'x', '2' ] ],
 264  *       [ [ 'x' ] ],
 265  *       [ [ 'y' ] ]
 266  *     );
 267  * returns:
 268  *     [
 269  *       [ 'x', '2' ],
 270  *       [ 'x' ],
 271  *       [ 'y' ]
 272  *     ]
 273  *
 274  * @param array $array1,...
 275  * @return array
 276  */
 277 function wfMergeErrorArrays( /*...*/ ) {
 278         $args = func_get_args();
 279         $out = [];
 280         foreach ( $args as $errors ) {
 281                 foreach ( $errors as $params ) {
 282                         $originalParams = $params;
 283                         if ( $params[0] instanceof MessageSpecifier ) {
 284                                 $msg = $params[0];
 285                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 286                         }
 287                         # @todo FIXME: Sometimes get nested arrays for $params,
 288                         # which leads to E_NOTICEs
 289                         $spec = implode( "\t", $params );
 290                         $out[$spec] = $originalParams;
 291                 }
 292         }
 293         return array_values( $out );
 294 }
 295
 296 /**
 297  * Insert array into another array after the specified *KEY*
 298  *
 299  * @param array $array The array.
 300  * @param array $insert The array to insert.
 301  * @param mixed $after The key to insert after
 302  * @return array
 303  */
 304 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 305         // Find the offset of the element to insert after.
 306         $keys = array_keys( $array );
 307         $offsetByKey = array_flip( $keys );
 308
 309         $offset = $offsetByKey[$after];
 310
 311         // Insert at the specified offset
 312         $before = array_slice( $array, 0, $offset + 1, true );
 313         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 314
 315         $output = $before + $insert + $after;
 316
 317         return $output;
 318 }
 319
 320 /**
 321  * Recursively converts the parameter (an object) to an array with the same data
 322  *
 323  * @param object|array $objOrArray
 324  * @param bool $recursive
 325  * @return array
 326  */
 327 function wfObjectToArray( $objOrArray, $recursive = true ) {
 328         $array = [];
 329         if ( is_object( $objOrArray ) ) {
 330                 $objOrArray = get_object_vars( $objOrArray );
 331         }
 332         foreach ( $objOrArray as $key => $value ) {
 333                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 334                         $value = wfObjectToArray( $value );
 335                 }
 336
 337                 $array[$key] = $value;
 338         }
 339
 340         return $array;
 341 }
 342
 343 /**
 344  * Get a random decimal value between 0 and 1, in a way
 345  * not likely to give duplicate values for any realistic
 346  * number of articles.
 347  *
 348  * @note This is designed for use in relation to Special:RandomPage
 349  *       and the page_random database field.
 350  *
 351  * @return string
 352  */
 353 function wfRandom() {
 354         // The maximum random value is "only" 2^31-1, so get two random
 355         // values to reduce the chance of dupes
 356         $max = mt_getrandmax() + 1;
 357         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 358         return $rand;
 359 }
 360
 361 /**
 362  * Get a random string containing a number of pseudo-random hex characters.
 363  *
 364  * @note This is not secure, if you are trying to generate some sort
 365  *       of token please use MWCryptRand instead.
 366  *
 367  * @param int $length The length of the string to generate
 368  * @return string
 369  * @since 1.20
 370  */
 371 function wfRandomString( $length = 32 ) {
 372         $str = '';
 373         for ( $n = 0; $n < $length; $n += 7 ) {
 374                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 375         }
 376         return substr( $str, 0, $length );
 377 }
 378
 379 /**
 380  * We want some things to be included as literal characters in our title URLs
 381  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 382  * all of the following should be safe:
 383  *
 384  * ;:@&=$-_.+!*'(),
 385  *
 386  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 387  * character which should not be encoded. More importantly, google chrome
 388  * always converts %7E back to ~, and converting it in this function can
 389  * cause a redirect loop (T105265).
 390  *
 391  * But + is not safe because it's used to indicate a space; &= are only safe in
 392  * paths and not in queries (and we don't distinguish here); ' seems kind of
 393  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 394  * is reserved, we don't care.  So the list we unescape is:
 395  *
 396  * ;:@$!*(),/~
 397  *
 398  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 399  * so no fancy : for IIS7.
 400  *
 401  * %2F in the page titles seems to fatally break for some reason.
 402  *
 403  * @param string $s
 404  * @return string
 405  */
 406 function wfUrlencode( $s ) {
 407         static $needle;
 408
 409         if ( is_null( $s ) ) {
 410                 $needle = null;
 411                 return '';
 412         }
 413
 414         if ( is_null( $needle ) ) {
 415                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 416                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 417                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 418                 ) {
 419                         $needle[] = '%3A';
 420                 }
 421         }
 422
 423         $s = urlencode( $s );
 424         $s = str_ireplace(
 425                 $needle,
 426                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 427                 $s
 428         );
 429
 430         return $s;
 431 }
 432
 433 /**
 434  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 435  * "days=7&limit=100". Options in the first array override options in the second.
 436  * Options set to null or false will not be output.
 437  *
 438  * @param array $array1 ( String|Array )
 439  * @param array|null $array2 ( String|Array )
 440  * @param string $prefix
 441  * @return string
 442  */
 443 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 444         if ( !is_null( $array2 ) ) {
 445                 $array1 = $array1 + $array2;
 446         }
 447
 448         $cgi = '';
 449         foreach ( $array1 as $key => $value ) {
 450                 if ( !is_null( $value ) && $value !== false ) {
 451                         if ( $cgi != '' ) {
 452                                 $cgi .= '&';
 453                         }
 454                         if ( $prefix !== '' ) {
 455                                 $key = $prefix . "[$key]";
 456                         }
 457                         if ( is_array( $value ) ) {
 458                                 $firstTime = true;
 459                                 foreach ( $value as $k => $v ) {
 460                                         $cgi .= $firstTime ? '' : '&';
 461                                         if ( is_array( $v ) ) {
 462                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 463                                         } else {
 464                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 465                                         }
 466                                         $firstTime = false;
 467                                 }
 468                         } else {
 469                                 if ( is_object( $value ) ) {
 470                                         $value = $value->__toString();
 471                                 }
 472                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 473                         }
 474                 }
 475         }
 476         return $cgi;
 477 }
 478
 479 /**
 480  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 481  * its argument and returns the same string in array form.  This allows compatibility
 482  * with legacy functions that accept raw query strings instead of nice
 483  * arrays.  Of course, keys and values are urldecode()d.
 484  *
 485  * @param string $query Query string
 486  * @return string[] Array version of input
 487  */
 488 function wfCgiToArray( $query ) {
 489         if ( isset( $query[0] ) && $query[0] == '?' ) {
 490                 $query = substr( $query, 1 );
 491         }
 492         $bits = explode( '&', $query );
 493         $ret = [];
 494         foreach ( $bits as $bit ) {
 495                 if ( $bit === '' ) {
 496                         continue;
 497                 }
 498                 if ( strpos( $bit, '=' ) === false ) {
 499                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 500                         $key = $bit;
 501                         $value = '';
 502                 } else {
 503                         list( $key, $value ) = explode( '=', $bit );
 504                 }
 505                 $key = urldecode( $key );
 506                 $value = urldecode( $value );
 507                 if ( strpos( $key, '[' ) !== false ) {
 508                         $keys = array_reverse( explode( '[', $key ) );
 509                         $key = array_pop( $keys );
 510                         $temp = $value;
 511                         foreach ( $keys as $k ) {
 512                                 $k = substr( $k, 0, -1 );
 513                                 $temp = [ $k => $temp ];
 514                         }
 515                         if ( isset( $ret[$key] ) ) {
 516                                 $ret[$key] = array_merge( $ret[$key], $temp );
 517                         } else {
 518                                 $ret[$key] = $temp;
 519                         }
 520                 } else {
 521                         $ret[$key] = $value;
 522                 }
 523         }
 524         return $ret;
 525 }
 526
 527 /**
 528  * Append a query string to an existing URL, which may or may not already
 529  * have query string parameters already. If so, they will be combined.
 530  *
 531  * @param string $url
 532  * @param string|string[] $query String or associative array
 533  * @return string
 534  */
 535 function wfAppendQuery( $url, $query ) {
 536         if ( is_array( $query ) ) {
 537                 $query = wfArrayToCgi( $query );
 538         }
 539         if ( $query != '' ) {
 540                 // Remove the fragment, if there is one
 541                 $fragment = false;
 542                 $hashPos = strpos( $url, '#' );
 543                 if ( $hashPos !== false ) {
 544                         $fragment = substr( $url, $hashPos );
 545                         $url = substr( $url, 0, $hashPos );
 546                 }
 547
 548                 // Add parameter
 549                 if ( false === strpos( $url, '?' ) ) {
 550                         $url .= '?';
 551                 } else {
 552                         $url .= '&';
 553                 }
 554                 $url .= $query;
 555
 556                 // Put the fragment back
 557                 if ( $fragment !== false ) {
 558                         $url .= $fragment;
 559                 }
 560         }
 561         return $url;
 562 }
 563
 564 /**
 565  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 566  * is correct.
 567  *
 568  * The meaning of the PROTO_* constants is as follows:
 569  * PROTO_HTTP: Output a URL starting with http://
 570  * PROTO_HTTPS: Output a URL starting with https://
 571  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 572  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 573  *    on which protocol was used for the current incoming request
 574  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 575  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 576  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 577  *
 578  * @todo this won't work with current-path-relative URLs
 579  * like "subdir/foo.html", etc.
 580  *
 581  * @param string $url Either fully-qualified or a local path + query
 582  * @param string $defaultProto One of the PROTO_* constants. Determines the
 583  *    protocol to use if $url or $wgServer is protocol-relative
 584  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 585  *    no valid URL can be constructed
 586  */
 587 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 588         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 589                 $wgHttpsPort;
 590         if ( $defaultProto === PROTO_CANONICAL ) {
 591                 $serverUrl = $wgCanonicalServer;
 592         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 593                 // Make $wgInternalServer fall back to $wgServer if not set
 594                 $serverUrl = $wgInternalServer;
 595         } else {
 596                 $serverUrl = $wgServer;
 597                 if ( $defaultProto === PROTO_CURRENT ) {
 598                         $defaultProto = $wgRequest->getProtocol() . '://';
 599                 }
 600         }
 601
 602         // Analyze $serverUrl to obtain its protocol
 603         $bits = wfParseUrl( $serverUrl );
 604         $serverHasProto = $bits && $bits['scheme'] != '';
 605
 606         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 607                 if ( $serverHasProto ) {
 608                         $defaultProto = $bits['scheme'] . '://';
 609                 } else {
 610                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 611                         // This really isn't supposed to happen. Fall back to HTTP in this
 612                         // ridiculous case.
 613                         $defaultProto = PROTO_HTTP;
 614                 }
 615         }
 616
 617         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 618
 619         if ( substr( $url, 0, 2 ) == '//' ) {
 620                 $url = $defaultProtoWithoutSlashes . $url;
 621         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 622                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 623                 // otherwise leave it alone.
 624                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 625         }
 626
 627         $bits = wfParseUrl( $url );
 628
 629         // ensure proper port for HTTPS arrives in URL
 630         // https://phabricator.wikimedia.org/T67184
 631         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 632                 $bits['port'] = $wgHttpsPort;
 633         }
 634
 635         if ( $bits && isset( $bits['path'] ) ) {
 636                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 637                 return wfAssembleUrl( $bits );
 638         } elseif ( $bits ) {
 639                 # No path to expand
 640                 return $url;
 641         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 642                 # URL is a relative path
 643                 return wfRemoveDotSegments( $url );
 644         }
 645
 646         # Expanded URL is not valid.
 647         return false;
 648 }
 649
 650 /**
 651  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 652  * if you need to edit part of a URL and put it back together.
 653  *
 654  * This is the basic structure used (brackets contain keys for $urlParts):
 655  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 656  *
 657  * @todo Need to integrate this into wfExpandUrl (see T34168)
 658  *
 659  * @since 1.19
 660  * @param array $urlParts URL parts, as output from wfParseUrl
 661  * @return string URL assembled from its component parts
 662  */
 663 function wfAssembleUrl( $urlParts ) {
 664         $result = '';
 665
 666         if ( isset( $urlParts['delimiter'] ) ) {
 667                 if ( isset( $urlParts['scheme'] ) ) {
 668                         $result .= $urlParts['scheme'];
 669                 }
 670
 671                 $result .= $urlParts['delimiter'];
 672         }
 673
 674         if ( isset( $urlParts['host'] ) ) {
 675                 if ( isset( $urlParts['user'] ) ) {
 676                         $result .= $urlParts['user'];
 677                         if ( isset( $urlParts['pass'] ) ) {
 678                                 $result .= ':' . $urlParts['pass'];
 679                         }
 680                         $result .= '@';
 681                 }
 682
 683                 $result .= $urlParts['host'];
 684
 685                 if ( isset( $urlParts['port'] ) ) {
 686                         $result .= ':' . $urlParts['port'];
 687                 }
 688         }
 689
 690         if ( isset( $urlParts['path'] ) ) {
 691                 $result .= $urlParts['path'];
 692         }
 693
 694         if ( isset( $urlParts['query'] ) ) {
 695                 $result .= '?' . $urlParts['query'];
 696         }
 697
 698         if ( isset( $urlParts['fragment'] ) ) {
 699                 $result .= '#' . $urlParts['fragment'];
 700         }
 701
 702         return $result;
 703 }
 704
 705 /**
 706  * Remove all dot-segments in the provided URL path.  For example,
 707  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 708  * RFC3986 section 5.2.4.
 709  *
 710  * @todo Need to integrate this into wfExpandUrl (see T34168)
 711  *
 712  * @param string $urlPath URL path, potentially containing dot-segments
 713  * @return string URL path with all dot-segments removed
 714  */
 715 function wfRemoveDotSegments( $urlPath ) {
 716         $output = '';
 717         $inputOffset = 0;
 718         $inputLength = strlen( $urlPath );
 719
 720         while ( $inputOffset < $inputLength ) {
 721                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 722                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 723                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 724                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 725                 $trimOutput = false;
 726
 727                 if ( $prefixLengthTwo == './' ) {
 728                         # Step A, remove leading "./"
 729                         $inputOffset += 2;
 730                 } elseif ( $prefixLengthThree == '../' ) {
 731                         # Step A, remove leading "../"
 732                         $inputOffset += 3;
 733                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 734                         # Step B, replace leading "/.$" with "/"
 735                         $inputOffset += 1;
 736                         $urlPath[$inputOffset] = '/';
 737                 } elseif ( $prefixLengthThree == '/./' ) {
 738                         # Step B, replace leading "/./" with "/"
 739                         $inputOffset += 2;
 740                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 741                         # Step C, replace leading "/..$" with "/" and
 742                         # remove last path component in output
 743                         $inputOffset += 2;
 744                         $urlPath[$inputOffset] = '/';
 745                         $trimOutput = true;
 746                 } elseif ( $prefixLengthFour == '/../' ) {
 747                         # Step C, replace leading "/../" with "/" and
 748                         # remove last path component in output
 749                         $inputOffset += 3;
 750                         $trimOutput = true;
 751                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 752                         # Step D, remove "^.$"
 753                         $inputOffset += 1;
 754                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 755                         # Step D, remove "^..$"
 756                         $inputOffset += 2;
 757                 } else {
 758                         # Step E, move leading path segment to output
 759                         if ( $prefixLengthOne == '/' ) {
 760                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 761                         } else {
 762                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 763                         }
 764                         if ( $slashPos === false ) {
 765                                 $output .= substr( $urlPath, $inputOffset );
 766                                 $inputOffset = $inputLength;
 767                         } else {
 768                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 769                                 $inputOffset += $slashPos - $inputOffset;
 770                         }
 771                 }
 772
 773                 if ( $trimOutput ) {
 774                         $slashPos = strrpos( $output, '/' );
 775                         if ( $slashPos === false ) {
 776                                 $output = '';
 777                         } else {
 778                                 $output = substr( $output, 0, $slashPos );
 779                         }
 780                 }
 781         }
 782
 783         return $output;
 784 }
 785
 786 /**
 787  * Returns a regular expression of url protocols
 788  *
 789  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 790  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 791  * @return string
 792  */
 793 function wfUrlProtocols( $includeProtocolRelative = true ) {
 794         global $wgUrlProtocols;
 795
 796         // Cache return values separately based on $includeProtocolRelative
 797         static $withProtRel = null, $withoutProtRel = null;
 798         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 799         if ( !is_null( $cachedValue ) ) {
 800                 return $cachedValue;
 801         }
 802
 803         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 804         // with LocalSettings files from 1.5
 805         if ( is_array( $wgUrlProtocols ) ) {
 806                 $protocols = [];
 807                 foreach ( $wgUrlProtocols as $protocol ) {
 808                         // Filter out '//' if !$includeProtocolRelative
 809                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 810                                 $protocols[] = preg_quote( $protocol, '/' );
 811                         }
 812                 }
 813
 814                 $retval = implode( '|', $protocols );
 815         } else {
 816                 // Ignore $includeProtocolRelative in this case
 817                 // This case exists for pre-1.6 compatibility, and we can safely assume
 818                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 819                 // URLs weren't supported until 1.18
 820                 $retval = $wgUrlProtocols;
 821         }
 822
 823         // Cache return value
 824         if ( $includeProtocolRelative ) {
 825                 $withProtRel = $retval;
 826         } else {
 827                 $withoutProtRel = $retval;
 828         }
 829         return $retval;
 830 }
 831
 832 /**
 833  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 834  * you need a regex that matches all URL protocols but does not match protocol-
 835  * relative URLs
 836  * @return string
 837  */
 838 function wfUrlProtocolsWithoutProtRel() {
 839         return wfUrlProtocols( false );
 840 }
 841
 842 /**
 843  * parse_url() work-alike, but non-broken.  Differences:
 844  *
 845  * 1) Does not raise warnings on bad URLs (just returns false).
 846  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 847  *    protocol-relative URLs) correctly.
 848  * 3) Adds a "delimiter" element to the array (see (2)).
 849  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 850  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 851  *    a line feed character.
 852  *
 853  * @param string $url A URL to parse
 854  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 855  *   Possible fields:
 856  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 857  *       be an empty string for protocol-relative URLs.
 858  *   - delimiter: either '://', ':' or '//'. Always present.
 859  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 860  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 861  *       Missing when there is no username.
 862  *   - pass: password, same as above.
 863  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 864  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 865  *   - fragment: the part after #, can be missing.
 866  */
 867 function wfParseUrl( $url ) {
 868         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 869
 870         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 871         // bad that the easiest way to handle them is to just prepend 'http:' and
 872         // strip the protocol out later.
 873         $wasRelative = substr( $url, 0, 2 ) == '//';
 874         if ( $wasRelative ) {
 875                 $url = "http:$url";
 876         }
 877         MediaWiki\suppressWarnings();
 878         $bits = parse_url( $url );
 879         MediaWiki\restoreWarnings();
 880         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 881         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 882         if ( !$bits || !isset( $bits['scheme'] ) ) {
 883                 return false;
 884         }
 885
 886         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 887         $bits['scheme'] = strtolower( $bits['scheme'] );
 888
 889         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 890         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 891                 $bits['delimiter'] = '://';
 892         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 893                 $bits['delimiter'] = ':';
 894                 // parse_url detects for news: and mailto: the host part of an url as path
 895                 // We have to correct this wrong detection
 896                 if ( isset( $bits['path'] ) ) {
 897                         $bits['host'] = $bits['path'];
 898                         $bits['path'] = '';
 899                 }
 900         } else {
 901                 return false;
 902         }
 903
 904         /* Provide an empty host for eg. file:/// urls (see T30627) */
 905         if ( !isset( $bits['host'] ) ) {
 906                 $bits['host'] = '';
 907
 908                 // See T47069
 909                 if ( isset( $bits['path'] ) ) {
 910                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 911                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 912                                 $bits['path'] = '/' . $bits['path'];
 913                         }
 914                 } else {
 915                         $bits['path'] = '';
 916                 }
 917         }
 918
 919         // If the URL was protocol-relative, fix scheme and delimiter
 920         if ( $wasRelative ) {
 921                 $bits['scheme'] = '';
 922                 $bits['delimiter'] = '//';
 923         }
 924         return $bits;
 925 }
 926
 927 /**
 928  * Take a URL, make sure it's expanded to fully qualified, and replace any
 929  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 930  * for more compact display and legibility for local audiences.
 931  *
 932  * @todo handle punycode domains too
 933  *
 934  * @param string $url
 935  * @return string
 936  */
 937 function wfExpandIRI( $url ) {
 938         return preg_replace_callback(
 939                 '/((?:%[89A-F][0-9A-F])+)/i',
 940                 'wfExpandIRI_callback',
 941                 wfExpandUrl( $url )
 942         );
 943 }
 944
 945 /**
 946  * Private callback for wfExpandIRI
 947  * @param array $matches
 948  * @return string
 949  */
 950 function wfExpandIRI_callback( $matches ) {
 951         return urldecode( $matches[1] );
 952 }
 953
 954 /**
 955  * Make URL indexes, appropriate for the el_index field of externallinks.
 956  *
 957  * @param string $url
 958  * @return array
 959  */
 960 function wfMakeUrlIndexes( $url ) {
 961         $bits = wfParseUrl( $url );
 962
 963         // Reverse the labels in the hostname, convert to lower case
 964         // For emails reverse domainpart only
 965         if ( $bits['scheme'] == 'mailto' ) {
 966                 $mailparts = explode( '@', $bits['host'], 2 );
 967                 if ( count( $mailparts ) === 2 ) {
 968                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 969                 } else {
 970                         // No domain specified, don't mangle it
 971                         $domainpart = '';
 972                 }
 973                 $reversedHost = $domainpart . '@' . $mailparts[0];
 974         } else {
 975                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 976         }
 977         // Add an extra dot to the end
 978         // Why? Is it in wrong place in mailto links?
 979         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 980                 $reversedHost .= '.';
 981         }
 982         // Reconstruct the pseudo-URL
 983         $prot = $bits['scheme'];
 984         $index = $prot . $bits['delimiter'] . $reversedHost;
 985         // Leave out user and password. Add the port, path, query and fragment
 986         if ( isset( $bits['port'] ) ) {
 987                 $index .= ':' . $bits['port'];
 988         }
 989         if ( isset( $bits['path'] ) ) {
 990                 $index .= $bits['path'];
 991         } else {
 992                 $index .= '/';
 993         }
 994         if ( isset( $bits['query'] ) ) {
 995                 $index .= '?' . $bits['query'];
 996         }
 997         if ( isset( $bits['fragment'] ) ) {
 998                 $index .= '#' . $bits['fragment'];
 999         }
1000
1001         if ( $prot == '' ) {
1002                 return [ "http:$index", "https:$index" ];
1003         } else {
1004                 return [ $index ];
1005         }
1006 }
1007
1008 /**
1009  * Check whether a given URL has a domain that occurs in a given set of domains
1010  * @param string $url URL
1011  * @param array $domains Array of domains (strings)
1012  * @return bool True if the host part of $url ends in one of the strings in $domains
1013  */
1014 function wfMatchesDomainList( $url, $domains ) {
1015         $bits = wfParseUrl( $url );
1016         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1017                 $host = '.' . $bits['host'];
1018                 foreach ( (array)$domains as $domain ) {
1019                         $domain = '.' . $domain;
1020                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1021                                 return true;
1022                         }
1023                 }
1024         }
1025         return false;
1026 }
1027
1028 /**
1029  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1030  * In normal operation this is a NOP.
1031  *
1032  * Controlling globals:
1033  * $wgDebugLogFile - points to the log file
1034  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1035  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1036  *
1037  * @since 1.25 support for additional context data
1038  *
1039  * @param string $text
1040  * @param string|bool $dest Destination of the message:
1041  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1042  *     - 'private': excluded from HTML output
1043  *   For backward compatibility, it can also take a boolean:
1044  *     - true: same as 'all'
1045  *     - false: same as 'private'
1046  * @param array $context Additional logging context data
1047  */
1048 function wfDebug( $text, $dest = 'all', array $context = [] ) {
1049         global $wgDebugRawPage, $wgDebugLogPrefix;
1050         global $wgDebugTimestamps, $wgRequestTime;
1051
1052         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1053                 return;
1054         }
1055
1056         $text = trim( $text );
1057
1058         if ( $wgDebugTimestamps ) {
1059                 $context['seconds_elapsed'] = sprintf(
1060                         '%6.4f',
1061                         microtime( true ) - $wgRequestTime
1062                 );
1063                 $context['memory_used'] = sprintf(
1064                         '%5.1fM',
1065                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1066                 );
1067         }
1068
1069         if ( $wgDebugLogPrefix !== '' ) {
1070                 $context['prefix'] = $wgDebugLogPrefix;
1071         }
1072         $context['private'] = ( $dest === false || $dest === 'private' );
1073
1074         $logger = LoggerFactory::getInstance( 'wfDebug' );
1075         $logger->debug( $text, $context );
1076 }
1077
1078 /**
1079  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1080  * @return bool
1081  */
1082 function wfIsDebugRawPage() {
1083         static $cache;
1084         if ( $cache !== null ) {
1085                 return $cache;
1086         }
1087         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1088         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1089                 || (
1090                         isset( $_SERVER['SCRIPT_NAME'] )
1091                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1092                 )
1093         ) {
1094                 $cache = true;
1095         } else {
1096                 $cache = false;
1097         }
1098         return $cache;
1099 }
1100
1101 /**
1102  * Send a line giving PHP memory usage.
1103  *
1104  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1105  */
1106 function wfDebugMem( $exact = false ) {
1107         $mem = memory_get_usage();
1108         if ( !$exact ) {
1109                 $mem = floor( $mem / 1024 ) . ' KiB';
1110         } else {
1111                 $mem .= ' B';
1112         }
1113         wfDebug( "Memory usage: $mem\n" );
1114 }
1115
1116 /**
1117  * Send a line to a supplementary debug log file, if configured, or main debug
1118  * log if not.
1119  *
1120  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1121  * a string filename or an associative array mapping 'destination' to the
1122  * desired filename. The associative array may also contain a 'sample' key
1123  * with an integer value, specifying a sampling factor. Sampled log events
1124  * will be emitted with a 1 in N random chance.
1125  *
1126  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1127  * @since 1.25 support for additional context data
1128  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1129  *
1130  * @param string $logGroup
1131  * @param string $text
1132  * @param string|bool $dest Destination of the message:
1133  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1134  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1135  *       discarded otherwise
1136  *   For backward compatibility, it can also take a boolean:
1137  *     - true: same as 'all'
1138  *     - false: same as 'private'
1139  * @param array $context Additional logging context data
1140  */
1141 function wfDebugLog(
1142         $logGroup, $text, $dest = 'all', array $context = []
1143 ) {
1144         $text = trim( $text );
1145
1146         $logger = LoggerFactory::getInstance( $logGroup );
1147         $context['private'] = ( $dest === false || $dest === 'private' );
1148         $logger->info( $text, $context );
1149 }
1150
1151 /**
1152  * Log for database errors
1153  *
1154  * @since 1.25 support for additional context data
1155  *
1156  * @param string $text Database error message.
1157  * @param array $context Additional logging context data
1158  */
1159 function wfLogDBError( $text, array $context = [] ) {
1160         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1161         $logger->error( trim( $text ), $context );
1162 }
1163
1164 /**
1165  * Throws a warning that $function is deprecated
1166  *
1167  * @param string $function
1168  * @param string|bool $version Version of MediaWiki that the function
1169  *    was deprecated in (Added in 1.19).
1170  * @param string|bool $component Added in 1.19.
1171  * @param int $callerOffset How far up the call stack is the original
1172  *    caller. 2 = function that called the function that called
1173  *    wfDeprecated (Added in 1.20)
1174  *
1175  * @return null
1176  */
1177 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1178         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1179 }
1180
1181 /**
1182  * Send a warning either to the debug log or in a PHP error depending on
1183  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1184  *
1185  * @param string $msg Message to send
1186  * @param int $callerOffset Number of items to go back in the backtrace to
1187  *        find the correct caller (1 = function calling wfWarn, ...)
1188  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1189  *        only used when $wgDevelopmentWarnings is true
1190  */
1191 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1192         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1193 }
1194
1195 /**
1196  * Send a warning as a PHP error and the debug log. This is intended for logging
1197  * warnings in production. For logging development warnings, use WfWarn instead.
1198  *
1199  * @param string $msg Message to send
1200  * @param int $callerOffset Number of items to go back in the backtrace to
1201  *        find the correct caller (1 = function calling wfLogWarning, ...)
1202  * @param int $level PHP error level; defaults to E_USER_WARNING
1203  */
1204 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1205         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1206 }
1207
1208 /**
1209  * Log to a file without getting "file size exceeded" signals.
1210  *
1211  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1212  * send lines to the specified port, prefixed by the specified prefix and a space.
1213  * @since 1.25 support for additional context data
1214  *
1215  * @param string $text
1216  * @param string $file Filename
1217  * @param array $context Additional logging context data
1218  * @throws MWException
1219  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1220  */
1221 function wfErrorLog( $text, $file, array $context = [] ) {
1222         wfDeprecated( __METHOD__, '1.25' );
1223         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1224         $context['destination'] = $file;
1225         $logger->info( trim( $text ), $context );
1226 }
1227
1228 /**
1229  * @todo document
1230  */
1231 function wfLogProfilingData() {
1232         global $wgDebugLogGroups, $wgDebugRawPage;
1233
1234         $context = RequestContext::getMain();
1235         $request = $context->getRequest();
1236
1237         $profiler = Profiler::instance();
1238         $profiler->setContext( $context );
1239         $profiler->logData();
1240
1241         $config = $context->getConfig();
1242         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1243         if ( $config->get( 'StatsdServer' ) && $stats->hasData() ) {
1244                 try {
1245                         $statsdServer = explode( ':', $config->get( 'StatsdServer' ) );
1246                         $statsdHost = $statsdServer[0];
1247                         $statsdPort = isset( $statsdServer[1] ) ? $statsdServer[1] : 8125;
1248                         $statsdSender = new SocketSender( $statsdHost, $statsdPort );
1249                         $statsdClient = new SamplingStatsdClient( $statsdSender, true, false );
1250                         $statsdClient->setSamplingRates( $config->get( 'StatsdSamplingRates' ) );
1251                         $statsdClient->send( $stats->getData() );
1252                 } catch ( Exception $ex ) {
1253                         MWExceptionHandler::logException( $ex );
1254                 }
1255         }
1256
1257         # Profiling must actually be enabled...
1258         if ( $profiler instanceof ProfilerStub ) {
1259                 return;
1260         }
1261
1262         if ( isset( $wgDebugLogGroups['profileoutput'] )
1263                 && $wgDebugLogGroups['profileoutput'] === false
1264         ) {
1265                 // Explicitly disabled
1266                 return;
1267         }
1268         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1269                 return;
1270         }
1271
1272         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1273         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1274                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1275         }
1276         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1277                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1278         }
1279         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1280                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1281         }
1282         if ( isset( $ctx['forwarded_for'] ) ||
1283                 isset( $ctx['client_ip'] ) ||
1284                 isset( $ctx['from'] ) ) {
1285                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1286         }
1287
1288         // Don't load $wgUser at this late stage just for statistics purposes
1289         // @todo FIXME: We can detect some anons even if it is not loaded.
1290         // See User::getId()
1291         $user = $context->getUser();
1292         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1293
1294         // Command line script uses a FauxRequest object which does not have
1295         // any knowledge about an URL and throw an exception instead.
1296         try {
1297                 $ctx['url'] = urldecode( $request->getRequestURL() );
1298         } catch ( Exception $ignored ) {
1299                 // no-op
1300         }
1301
1302         $ctx['output'] = $profiler->getOutput();
1303
1304         $log = LoggerFactory::getInstance( 'profileoutput' );
1305         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1306 }
1307
1308 /**
1309  * Increment a statistics counter
1310  *
1311  * @param string $key
1312  * @param int $count
1313  * @return void
1314  */
1315 function wfIncrStats( $key, $count = 1 ) {
1316         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1317         $stats->updateCount( $key, $count );
1318 }
1319
1320 /**
1321  * Check whether the wiki is in read-only mode.
1322  *
1323  * @return bool
1324  */
1325 function wfReadOnly() {
1326         return MediaWikiServices::getInstance()->getReadOnlyMode()
1327                 ->isReadOnly();
1328 }
1329
1330 /**
1331  * Check if the site is in read-only mode and return the message if so
1332  *
1333  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1334  * for replica DB lag. This may result in DB connection being made.
1335  *
1336  * @return string|bool String when in read-only mode; false otherwise
1337  */
1338 function wfReadOnlyReason() {
1339         return MediaWikiServices::getInstance()->getReadOnlyMode()
1340                 ->getReason();
1341 }
1342
1343 /**
1344  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1345  *
1346  * @return string|bool String when in read-only mode; false otherwise
1347  * @since 1.27
1348  */
1349 function wfConfiguredReadOnlyReason() {
1350         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1351                 ->getReason();
1352 }
1353
1354 /**
1355  * Return a Language object from $langcode
1356  *
1357  * @param Language|string|bool $langcode Either:
1358  *                  - a Language object
1359  *                  - code of the language to get the message for, if it is
1360  *                    a valid code create a language for that language, if
1361  *                    it is a string but not a valid code then make a basic
1362  *                    language object
1363  *                  - a boolean: if it's false then use the global object for
1364  *                    the current user's language (as a fallback for the old parameter
1365  *                    functionality), or if it is true then use global object
1366  *                    for the wiki's content language.
1367  * @return Language
1368  */
1369 function wfGetLangObj( $langcode = false ) {
1370         # Identify which language to get or create a language object for.
1371         # Using is_object here due to Stub objects.
1372         if ( is_object( $langcode ) ) {
1373                 # Great, we already have the object (hopefully)!
1374                 return $langcode;
1375         }
1376
1377         global $wgContLang, $wgLanguageCode;
1378         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1379                 # $langcode is the language code of the wikis content language object.
1380                 # or it is a boolean and value is true
1381                 return $wgContLang;
1382         }
1383
1384         global $wgLang;
1385         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1386                 # $langcode is the language code of user language object.
1387                 # or it was a boolean and value is false
1388                 return $wgLang;
1389         }
1390
1391         $validCodes = array_keys( Language::fetchLanguageNames() );
1392         if ( in_array( $langcode, $validCodes ) ) {
1393                 # $langcode corresponds to a valid language.
1394                 return Language::factory( $langcode );
1395         }
1396
1397         # $langcode is a string, but not a valid language code; use content language.
1398         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1399         return $wgContLang;
1400 }
1401
1402 /**
1403  * This is the function for getting translated interface messages.
1404  *
1405  * @see Message class for documentation how to use them.
1406  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1407  *
1408  * This function replaces all old wfMsg* functions.
1409  *
1410  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1411  * @param mixed $params,... Normal message parameters
1412  * @return Message
1413  *
1414  * @since 1.17
1415  *
1416  * @see Message::__construct
1417  */
1418 function wfMessage( $key /*...*/ ) {
1419         $message = new Message( $key );
1420
1421         // We call Message::params() to reduce code duplication
1422         $params = func_get_args();
1423         array_shift( $params );
1424         if ( $params ) {
1425                 call_user_func_array( [ $message, 'params' ], $params );
1426         }
1427
1428         return $message;
1429 }
1430
1431 /**
1432  * This function accepts multiple message keys and returns a message instance
1433  * for the first message which is non-empty. If all messages are empty then an
1434  * instance of the first message key is returned.
1435  *
1436  * @param string|string[] $keys,... Message keys
1437  * @return Message
1438  *
1439  * @since 1.18
1440  *
1441  * @see Message::newFallbackSequence
1442  */
1443 function wfMessageFallback( /*...*/ ) {
1444         $args = func_get_args();
1445         return call_user_func_array( 'Message::newFallbackSequence', $args );
1446 }
1447
1448 /**
1449  * Replace message parameter keys on the given formatted output.
1450  *
1451  * @param string $message
1452  * @param array $args
1453  * @return string
1454  * @private
1455  */
1456 function wfMsgReplaceArgs( $message, $args ) {
1457         # Fix windows line-endings
1458         # Some messages are split with explode("\n", $msg)
1459         $message = str_replace( "\r", '', $message );
1460
1461         // Replace arguments
1462         if ( is_array( $args ) && $args ) {
1463                 if ( is_array( $args[0] ) ) {
1464                         $args = array_values( $args[0] );
1465                 }
1466                 $replacementKeys = [];
1467                 foreach ( $args as $n => $param ) {
1468                         $replacementKeys['$' . ( $n + 1 )] = $param;
1469                 }
1470                 $message = strtr( $message, $replacementKeys );
1471         }
1472
1473         return $message;
1474 }
1475
1476 /**
1477  * Fetch server name for use in error reporting etc.
1478  * Use real server name if available, so we know which machine
1479  * in a server farm generated the current page.
1480  *
1481  * @return string
1482  */
1483 function wfHostname() {
1484         static $host;
1485         if ( is_null( $host ) ) {
1486                 # Hostname overriding
1487                 global $wgOverrideHostname;
1488                 if ( $wgOverrideHostname !== false ) {
1489                         # Set static and skip any detection
1490                         $host = $wgOverrideHostname;
1491                         return $host;
1492                 }
1493
1494                 if ( function_exists( 'posix_uname' ) ) {
1495                         // This function not present on Windows
1496                         $uname = posix_uname();
1497                 } else {
1498                         $uname = false;
1499                 }
1500                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1501                         $host = $uname['nodename'];
1502                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1503                         # Windows computer name
1504                         $host = getenv( 'COMPUTERNAME' );
1505                 } else {
1506                         # This may be a virtual server.
1507                         $host = $_SERVER['SERVER_NAME'];
1508                 }
1509         }
1510         return $host;
1511 }
1512
1513 /**
1514  * Returns a script tag that stores the amount of time it took MediaWiki to
1515  * handle the request in milliseconds as 'wgBackendResponseTime'.
1516  *
1517  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1518  * hostname of the server handling the request.
1519  *
1520  * @return string
1521  */
1522 function wfReportTime() {
1523         global $wgRequestTime, $wgShowHostnames;
1524
1525         $responseTime = round( ( microtime( true ) - $wgRequestTime ) * 1000 );
1526         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1527         if ( $wgShowHostnames ) {
1528                 $reportVars['wgHostname'] = wfHostname();
1529         }
1530         return Skin::makeVariablesScript( $reportVars );
1531 }
1532
1533 /**
1534  * Safety wrapper for debug_backtrace().
1535  *
1536  * Will return an empty array if debug_backtrace is disabled, otherwise
1537  * the output from debug_backtrace() (trimmed).
1538  *
1539  * @param int $limit This parameter can be used to limit the number of stack frames returned
1540  *
1541  * @return array Array of backtrace information
1542  */
1543 function wfDebugBacktrace( $limit = 0 ) {
1544         static $disabled = null;
1545
1546         if ( is_null( $disabled ) ) {
1547                 $disabled = !function_exists( 'debug_backtrace' );
1548                 if ( $disabled ) {
1549                         wfDebug( "debug_backtrace() is disabled\n" );
1550                 }
1551         }
1552         if ( $disabled ) {
1553                 return [];
1554         }
1555
1556         if ( $limit ) {
1557                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1558         } else {
1559                 return array_slice( debug_backtrace(), 1 );
1560         }
1561 }
1562
1563 /**
1564  * Get a debug backtrace as a string
1565  *
1566  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1567  *   Defaults to $wgCommandLineMode if unset.
1568  * @return string
1569  * @since 1.25 Supports $raw parameter.
1570  */
1571 function wfBacktrace( $raw = null ) {
1572         global $wgCommandLineMode;
1573
1574         if ( $raw === null ) {
1575                 $raw = $wgCommandLineMode;
1576         }
1577
1578         if ( $raw ) {
1579                 $frameFormat = "%s line %s calls %s()\n";
1580                 $traceFormat = "%s";
1581         } else {
1582                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1583                 $traceFormat = "<ul>\n%s</ul>\n";
1584         }
1585
1586         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1587                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1588                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1589                 $call = $frame['function'];
1590                 if ( !empty( $frame['class'] ) ) {
1591                         $call = $frame['class'] . $frame['type'] . $call;
1592                 }
1593                 return sprintf( $frameFormat, $file, $line, $call );
1594         }, wfDebugBacktrace() );
1595
1596         return sprintf( $traceFormat, implode( '', $frames ) );
1597 }
1598
1599 /**
1600  * Get the name of the function which called this function
1601  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1602  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1603  * wfGetCaller( 3 ) is the parent of that.
1604  *
1605  * @param int $level
1606  * @return string
1607  */
1608 function wfGetCaller( $level = 2 ) {
1609         $backtrace = wfDebugBacktrace( $level + 1 );
1610         if ( isset( $backtrace[$level] ) ) {
1611                 return wfFormatStackFrame( $backtrace[$level] );
1612         } else {
1613                 return 'unknown';
1614         }
1615 }
1616
1617 /**
1618  * Return a string consisting of callers in the stack. Useful sometimes
1619  * for profiling specific points.
1620  *
1621  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1622  * @return string
1623  */
1624 function wfGetAllCallers( $limit = 3 ) {
1625         $trace = array_reverse( wfDebugBacktrace() );
1626         if ( !$limit || $limit > count( $trace ) - 1 ) {
1627                 $limit = count( $trace ) - 1;
1628         }
1629         $trace = array_slice( $trace, -$limit - 1, $limit );
1630         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1631 }
1632
1633 /**
1634  * Return a string representation of frame
1635  *
1636  * @param array $frame
1637  * @return string
1638  */
1639 function wfFormatStackFrame( $frame ) {
1640         if ( !isset( $frame['function'] ) ) {
1641                 return 'NO_FUNCTION_GIVEN';
1642         }
1643         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1644                 $frame['class'] . $frame['type'] . $frame['function'] :
1645                 $frame['function'];
1646 }
1647
1648 /* Some generic result counters, pulled out of SearchEngine */
1649
1650 /**
1651  * @todo document
1652  *
1653  * @param int $offset
1654  * @param int $limit
1655  * @return string
1656  */
1657 function wfShowingResults( $offset, $limit ) {
1658         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1659 }
1660
1661 /**
1662  * Whether the client accept gzip encoding
1663  *
1664  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1665  * Use this when considering to send a gzip-encoded response to the client.
1666  *
1667  * @param bool $force Forces another check even if we already have a cached result.
1668  * @return bool
1669  */
1670 function wfClientAcceptsGzip( $force = false ) {
1671         static $result = null;
1672         if ( $result === null || $force ) {
1673                 $result = false;
1674                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1675                         # @todo FIXME: We may want to blacklist some broken browsers
1676                         $m = [];
1677                         if ( preg_match(
1678                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1679                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1680                                         $m
1681                                 )
1682                         ) {
1683                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1684                                         $result = false;
1685                                         return $result;
1686                                 }
1687                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1688                                 $result = true;
1689                         }
1690                 }
1691         }
1692         return $result;
1693 }
1694
1695 /**
1696  * Escapes the given text so that it may be output using addWikiText()
1697  * without any linking, formatting, etc. making its way through. This
1698  * is achieved by substituting certain characters with HTML entities.
1699  * As required by the callers, "<nowiki>" is not used.
1700  *
1701  * @param string $text Text to be escaped
1702  * @return string
1703  */
1704 function wfEscapeWikiText( $text ) {
1705         global $wgEnableMagicLinks;
1706         static $repl = null, $repl2 = null;
1707         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1708                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1709                 // in those situations
1710                 $repl = [
1711                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1712                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1713                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1714                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1715                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1716                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1717                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1718                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1719                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1720                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1721                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1722                         '__' => '_&#95;', '://' => '&#58;//',
1723                 ];
1724
1725                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1726                 // We have to catch everything "\s" matches in PCRE
1727                 foreach ( $magicLinks as $magic ) {
1728                         $repl["$magic "] = "$magic&#32;";
1729                         $repl["$magic\t"] = "$magic&#9;";
1730                         $repl["$magic\r"] = "$magic&#13;";
1731                         $repl["$magic\n"] = "$magic&#10;";
1732                         $repl["$magic\f"] = "$magic&#12;";
1733                 }
1734
1735                 // And handle protocols that don't use "://"
1736                 global $wgUrlProtocols;
1737                 $repl2 = [];
1738                 foreach ( $wgUrlProtocols as $prot ) {
1739                         if ( substr( $prot, -1 ) === ':' ) {
1740                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1741                         }
1742                 }
1743                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1744         }
1745         $text = substr( strtr( "\n$text", $repl ), 1 );
1746         $text = preg_replace( $repl2, '$1&#58;', $text );
1747         return $text;
1748 }
1749
1750 /**
1751  * Sets dest to source and returns the original value of dest
1752  * If source is NULL, it just returns the value, it doesn't set the variable
1753  * If force is true, it will set the value even if source is NULL
1754  *
1755  * @param mixed &$dest
1756  * @param mixed $source
1757  * @param bool $force
1758  * @return mixed
1759  */
1760 function wfSetVar( &$dest, $source, $force = false ) {
1761         $temp = $dest;
1762         if ( !is_null( $source ) || $force ) {
1763                 $dest = $source;
1764         }
1765         return $temp;
1766 }
1767
1768 /**
1769  * As for wfSetVar except setting a bit
1770  *
1771  * @param int &$dest
1772  * @param int $bit
1773  * @param bool $state
1774  *
1775  * @return bool
1776  */
1777 function wfSetBit( &$dest, $bit, $state = true ) {
1778         $temp = (bool)( $dest & $bit );
1779         if ( !is_null( $state ) ) {
1780                 if ( $state ) {
1781                         $dest |= $bit;
1782                 } else {
1783                         $dest &= ~$bit;
1784                 }
1785         }
1786         return $temp;
1787 }
1788
1789 /**
1790  * A wrapper around the PHP function var_export().
1791  * Either print it or add it to the regular output ($wgOut).
1792  *
1793  * @param mixed $var A PHP variable to dump.
1794  */
1795 function wfVarDump( $var ) {
1796         global $wgOut;
1797         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1798         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1799                 print $s;
1800         } else {
1801                 $wgOut->addHTML( $s );
1802         }
1803 }
1804
1805 /**
1806  * Provide a simple HTTP error.
1807  *
1808  * @param int|string $code
1809  * @param string $label
1810  * @param string $desc
1811  */
1812 function wfHttpError( $code, $label, $desc ) {
1813         global $wgOut;
1814         HttpStatus::header( $code );
1815         if ( $wgOut ) {
1816                 $wgOut->disable();
1817                 $wgOut->sendCacheControl();
1818         }
1819
1820         MediaWiki\HeaderCallback::warnIfHeadersSent();
1821         header( 'Content-type: text/html; charset=utf-8' );
1822         print '<!DOCTYPE html>' .
1823                 '<html><head><title>' .
1824                 htmlspecialchars( $label ) .
1825                 '</title></head><body><h1>' .
1826                 htmlspecialchars( $label ) .
1827                 '</h1><p>' .
1828                 nl2br( htmlspecialchars( $desc ) ) .
1829                 "</p></body></html>\n";
1830 }
1831
1832 /**
1833  * Clear away any user-level output buffers, discarding contents.
1834  *
1835  * Suitable for 'starting afresh', for instance when streaming
1836  * relatively large amounts of data without buffering, or wanting to
1837  * output image files without ob_gzhandler's compression.
1838  *
1839  * The optional $resetGzipEncoding parameter controls suppression of
1840  * the Content-Encoding header sent by ob_gzhandler; by default it
1841  * is left. See comments for wfClearOutputBuffers() for why it would
1842  * be used.
1843  *
1844  * Note that some PHP configuration options may add output buffer
1845  * layers which cannot be removed; these are left in place.
1846  *
1847  * @param bool $resetGzipEncoding
1848  */
1849 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1850         if ( $resetGzipEncoding ) {
1851                 // Suppress Content-Encoding and Content-Length
1852                 // headers from 1.10+s wfOutputHandler
1853                 global $wgDisableOutputCompression;
1854                 $wgDisableOutputCompression = true;
1855         }
1856         while ( $status = ob_get_status() ) {
1857                 if ( isset( $status['flags'] ) ) {
1858                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1859                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1860                 } elseif ( isset( $status['del'] ) ) {
1861                         $deleteable = $status['del'];
1862                 } else {
1863                         // Guess that any PHP-internal setting can't be removed.
1864                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1865                 }
1866                 if ( !$deleteable ) {
1867                         // Give up, and hope the result doesn't break
1868                         // output behavior.
1869                         break;
1870                 }
1871                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1872                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1873                         break;
1874                 }
1875                 if ( !ob_end_clean() ) {
1876                         // Could not remove output buffer handler; abort now
1877                         // to avoid getting in some kind of infinite loop.
1878                         break;
1879                 }
1880                 if ( $resetGzipEncoding ) {
1881                         if ( $status['name'] == 'ob_gzhandler' ) {
1882                                 // Reset the 'Content-Encoding' field set by this handler
1883                                 // so we can start fresh.
1884                                 header_remove( 'Content-Encoding' );
1885                                 break;
1886                         }
1887                 }
1888         }
1889 }
1890
1891 /**
1892  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1893  *
1894  * Clear away output buffers, but keep the Content-Encoding header
1895  * produced by ob_gzhandler, if any.
1896  *
1897  * This should be used for HTTP 304 responses, where you need to
1898  * preserve the Content-Encoding header of the real result, but
1899  * also need to suppress the output of ob_gzhandler to keep to spec
1900  * and avoid breaking Firefox in rare cases where the headers and
1901  * body are broken over two packets.
1902  */
1903 function wfClearOutputBuffers() {
1904         wfResetOutputBuffers( false );
1905 }
1906
1907 /**
1908  * Converts an Accept-* header into an array mapping string values to quality
1909  * factors
1910  *
1911  * @param string $accept
1912  * @param string $def Default
1913  * @return float[] Associative array of string => float pairs
1914  */
1915 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1916         # No arg means accept anything (per HTTP spec)
1917         if ( !$accept ) {
1918                 return [ $def => 1.0 ];
1919         }
1920
1921         $prefs = [];
1922
1923         $parts = explode( ',', $accept );
1924
1925         foreach ( $parts as $part ) {
1926                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1927                 $values = explode( ';', trim( $part ) );
1928                 $match = [];
1929                 if ( count( $values ) == 1 ) {
1930                         $prefs[$values[0]] = 1.0;
1931                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1932                         $prefs[$values[0]] = floatval( $match[1] );
1933                 }
1934         }
1935
1936         return $prefs;
1937 }
1938
1939 /**
1940  * Checks if a given MIME type matches any of the keys in the given
1941  * array. Basic wildcards are accepted in the array keys.
1942  *
1943  * Returns the matching MIME type (or wildcard) if a match, otherwise
1944  * NULL if no match.
1945  *
1946  * @param string $type
1947  * @param array $avail
1948  * @return string
1949  * @private
1950  */
1951 function mimeTypeMatch( $type, $avail ) {
1952         if ( array_key_exists( $type, $avail ) ) {
1953                 return $type;
1954         } else {
1955                 $mainType = explode( '/', $type )[0];
1956                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1957                         return "$mainType/*";
1958                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1959                         return '*/*';
1960                 } else {
1961                         return null;
1962                 }
1963         }
1964 }
1965
1966 /**
1967  * Returns the 'best' match between a client's requested internet media types
1968  * and the server's list of available types. Each list should be an associative
1969  * array of type to preference (preference is a float between 0.0 and 1.0).
1970  * Wildcards in the types are acceptable.
1971  *
1972  * @param array $cprefs Client's acceptable type list
1973  * @param array $sprefs Server's offered types
1974  * @return string
1975  *
1976  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1977  * XXX: generalize to negotiate other stuff
1978  */
1979 function wfNegotiateType( $cprefs, $sprefs ) {
1980         $combine = [];
1981
1982         foreach ( array_keys( $sprefs ) as $type ) {
1983                 $subType = explode( '/', $type )[1];
1984                 if ( $subType != '*' ) {
1985                         $ckey = mimeTypeMatch( $type, $cprefs );
1986                         if ( $ckey ) {
1987                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1988                         }
1989                 }
1990         }
1991
1992         foreach ( array_keys( $cprefs ) as $type ) {
1993                 $subType = explode( '/', $type )[1];
1994                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1995                         $skey = mimeTypeMatch( $type, $sprefs );
1996                         if ( $skey ) {
1997                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1998                         }
1999                 }
2000         }
2001
2002         $bestq = 0;
2003         $besttype = null;
2004
2005         foreach ( array_keys( $combine ) as $type ) {
2006                 if ( $combine[$type] > $bestq ) {
2007                         $besttype = $type;
2008                         $bestq = $combine[$type];
2009                 }
2010         }
2011
2012         return $besttype;
2013 }
2014
2015 /**
2016  * Reference-counted warning suppression
2017  *
2018  * @deprecated since 1.26, use MediaWiki\suppressWarnings() directly
2019  * @param bool $end
2020  */
2021 function wfSuppressWarnings( $end = false ) {
2022         MediaWiki\suppressWarnings( $end );
2023 }
2024
2025 /**
2026  * @deprecated since 1.26, use MediaWiki\restoreWarnings() directly
2027  * Restore error level to previous value
2028  */
2029 function wfRestoreWarnings() {
2030         MediaWiki\suppressWarnings( true );
2031 }
2032
2033 /**
2034  * Get a timestamp string in one of various formats
2035  *
2036  * @param mixed $outputtype A timestamp in one of the supported formats, the
2037  *   function will autodetect which format is supplied and act accordingly.
2038  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2039  * @return string|bool String / false The same date in the format specified in $outputtype or false
2040  */
2041 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2042         $ret = MWTimestamp::convert( $outputtype, $ts );
2043         if ( $ret === false ) {
2044                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2045         }
2046         return $ret;
2047 }
2048
2049 /**
2050  * Return a formatted timestamp, or null if input is null.
2051  * For dealing with nullable timestamp columns in the database.
2052  *
2053  * @param int $outputtype
2054  * @param string $ts
2055  * @return string
2056  */
2057 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2058         if ( is_null( $ts ) ) {
2059                 return null;
2060         } else {
2061                 return wfTimestamp( $outputtype, $ts );
2062         }
2063 }
2064
2065 /**
2066  * Convenience function; returns MediaWiki timestamp for the present time.
2067  *
2068  * @return string
2069  */
2070 function wfTimestampNow() {
2071         # return NOW
2072         return MWTimestamp::now( TS_MW );
2073 }
2074
2075 /**
2076  * Check if the operating system is Windows
2077  *
2078  * @return bool True if it's Windows, false otherwise.
2079  */
2080 function wfIsWindows() {
2081         static $isWindows = null;
2082         if ( $isWindows === null ) {
2083                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2084         }
2085         return $isWindows;
2086 }
2087
2088 /**
2089  * Check if we are running under HHVM
2090  *
2091  * @return bool
2092  */
2093 function wfIsHHVM() {
2094         return defined( 'HHVM_VERSION' );
2095 }
2096
2097 /**
2098  * Tries to get the system directory for temporary files. First
2099  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2100  * environment variables are then checked in sequence, then
2101  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2102  *
2103  * NOTE: When possible, use instead the tmpfile() function to create
2104  * temporary files to avoid race conditions on file creation, etc.
2105  *
2106  * @return string
2107  */
2108 function wfTempDir() {
2109         global $wgTmpDirectory;
2110
2111         if ( $wgTmpDirectory !== false ) {
2112                 return $wgTmpDirectory;
2113         }
2114
2115         return TempFSFile::getUsableTempDirectory();
2116 }
2117
2118 /**
2119  * Make directory, and make all parent directories if they don't exist
2120  *
2121  * @param string $dir Full path to directory to create
2122  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2123  * @param string $caller Optional caller param for debugging.
2124  * @throws MWException
2125  * @return bool
2126  */
2127 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2128         global $wgDirectoryMode;
2129
2130         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2131                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2132         }
2133
2134         if ( !is_null( $caller ) ) {
2135                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2136         }
2137
2138         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2139                 return true;
2140         }
2141
2142         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2143
2144         if ( is_null( $mode ) ) {
2145                 $mode = $wgDirectoryMode;
2146         }
2147
2148         // Turn off the normal warning, we're doing our own below
2149         MediaWiki\suppressWarnings();
2150         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2151         MediaWiki\restoreWarnings();
2152
2153         if ( !$ok ) {
2154                 // directory may have been created on another request since we last checked
2155                 if ( is_dir( $dir ) ) {
2156                         return true;
2157                 }
2158
2159                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2160                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2161         }
2162         return $ok;
2163 }
2164
2165 /**
2166  * Remove a directory and all its content.
2167  * Does not hide error.
2168  * @param string $dir
2169  */
2170 function wfRecursiveRemoveDir( $dir ) {
2171         wfDebug( __FUNCTION__ . "( $dir )\n" );
2172         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2173         if ( is_dir( $dir ) ) {
2174                 $objects = scandir( $dir );
2175                 foreach ( $objects as $object ) {
2176                         if ( $object != "." && $object != ".." ) {
2177                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2178                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2179                                 } else {
2180                                         unlink( $dir . '/' . $object );
2181                                 }
2182                         }
2183                 }
2184                 reset( $objects );
2185                 rmdir( $dir );
2186         }
2187 }
2188
2189 /**
2190  * @param int $nr The number to format
2191  * @param int $acc The number of digits after the decimal point, default 2
2192  * @param bool $round Whether or not to round the value, default true
2193  * @return string
2194  */
2195 function wfPercent( $nr, $acc = 2, $round = true ) {
2196         $ret = sprintf( "%.${acc}f", $nr );
2197         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2198 }
2199
2200 /**
2201  * Safety wrapper around ini_get() for boolean settings.
2202  * The values returned from ini_get() are pre-normalized for settings
2203  * set via php.ini or php_flag/php_admin_flag... but *not*
2204  * for those set via php_value/php_admin_value.
2205  *
2206  * It's fairly common for people to use php_value instead of php_flag,
2207  * which can leave you with an 'off' setting giving a false positive
2208  * for code that just takes the ini_get() return value as a boolean.
2209  *
2210  * To make things extra interesting, setting via php_value accepts
2211  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2212  * Unrecognized values go false... again opposite PHP's own coercion
2213  * from string to bool.
2214  *
2215  * Luckily, 'properly' set settings will always come back as '0' or '1',
2216  * so we only have to worry about them and the 'improper' settings.
2217  *
2218  * I frickin' hate PHP... :P
2219  *
2220  * @param string $setting
2221  * @return bool
2222  */
2223 function wfIniGetBool( $setting ) {
2224         $val = strtolower( ini_get( $setting ) );
2225         // 'on' and 'true' can't have whitespace around them, but '1' can.
2226         return $val == 'on'
2227                 || $val == 'true'
2228                 || $val == 'yes'
2229                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2230 }
2231
2232 /**
2233  * Version of escapeshellarg() that works better on Windows.
2234  *
2235  * Originally, this fixed the incorrect use of single quotes on Windows
2236  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2237  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2238  *
2239  * @param string $args,... strings to escape and glue together,
2240  *  or a single array of strings parameter
2241  * @return string
2242  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2243  */
2244 function wfEscapeShellArg( /*...*/ ) {
2245         $args = func_get_args();
2246
2247         return call_user_func_array( Shell::class . '::escape', $args );
2248 }
2249
2250 /**
2251  * Check if wfShellExec() is effectively disabled via php.ini config
2252  *
2253  * @return bool|string False or 'disabled'
2254  * @since 1.22
2255  * @deprecated since 1.30 use MediaWiki\Shell::isDisabled()
2256  */
2257 function wfShellExecDisabled() {
2258         return Shell::isDisabled() ? 'disabled' : false;
2259 }
2260
2261 /**
2262  * Execute a shell command, with time and memory limits mirrored from the PHP
2263  * configuration if supported.
2264  *
2265  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2266  *   or an array of unescaped arguments, in which case each value will be escaped
2267  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2268  * @param null|mixed &$retval Optional, will receive the program's exit code.
2269  *   (non-zero is usually failure). If there is an error from
2270  *   read, select, or proc_open(), this will be set to -1.
2271  * @param array $environ Optional environment variables which should be
2272  *   added to the executed command environment.
2273  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2274  *   this overwrites the global wgMaxShell* limits.
2275  * @param array $options Array of options:
2276  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2277  *     including errors from limit.sh
2278  *   - profileMethod: By default this function will profile based on the calling
2279  *     method. Set this to a string for an alternative method to profile from
2280  *
2281  * @return string Collected stdout as a string
2282  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2283  */
2284 function wfShellExec( $cmd, &$retval = null, $environ = [],
2285         $limits = [], $options = []
2286 ) {
2287         if ( Shell::isDisabled() ) {
2288                 $retval = 1;
2289                 // Backwards compatibility be upon us...
2290                 return 'Unable to run external programs, proc_open() is disabled.';
2291         }
2292
2293         if ( is_array( $cmd ) ) {
2294                 $cmd = Shell::escape( $cmd );
2295         }
2296
2297         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2298         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2299
2300         try {
2301                 $result = Shell::command( [] )
2302                         ->unsafeParams( (array)$cmd )
2303                         ->environment( $environ )
2304                         ->limits( $limits )
2305                         ->includeStderr( $includeStderr )
2306                         ->profileMethod( $profileMethod )
2307                         ->execute();
2308         } catch ( ProcOpenError $ex ) {
2309                 $retval = -1;
2310                 return '';
2311         }
2312
2313         $retval = $result->getExitCode();
2314
2315         return $result->getStdout();
2316 }
2317
2318 /**
2319  * Execute a shell command, returning both stdout and stderr. Convenience
2320  * function, as all the arguments to wfShellExec can become unwieldy.
2321  *
2322  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2323  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2324  *   or an array of unescaped arguments, in which case each value will be escaped
2325  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2326  * @param null|mixed &$retval Optional, will receive the program's exit code.
2327  *   (non-zero is usually failure)
2328  * @param array $environ Optional environment variables which should be
2329  *   added to the executed command environment.
2330  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2331  *   this overwrites the global wgMaxShell* limits.
2332  * @return string Collected stdout and stderr as a string
2333  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2334  */
2335 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2336         return wfShellExec( $cmd, $retval, $environ, $limits,
2337                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2338 }
2339
2340 /**
2341  * Formerly set the locale for locale-sensitive operations
2342  *
2343  * This is now done in Setup.php.
2344  *
2345  * @deprecated since 1.30, no longer needed
2346  * @see $wgShellLocale
2347  */
2348 function wfInitShellLocale() {
2349 }
2350
2351 /**
2352  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2353  * Note that $parameters should be a flat array and an option with an argument
2354  * should consist of two consecutive items in the array (do not use "--option value").
2355  *
2356  * @param string $script MediaWiki cli script path
2357  * @param array $parameters Arguments and options to the script
2358  * @param array $options Associative array of options:
2359  *     'php': The path to the php executable
2360  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2361  * @return string
2362  */
2363 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2364         global $wgPhpCli;
2365         // Give site config file a chance to run the script in a wrapper.
2366         // The caller may likely want to call wfBasename() on $script.
2367         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2368         $cmd = isset( $options['php'] ) ? [ $options['php'] ] : [ $wgPhpCli ];
2369         if ( isset( $options['wrapper'] ) ) {
2370                 $cmd[] = $options['wrapper'];
2371         }
2372         $cmd[] = $script;
2373         // Escape each parameter for shell
2374         return Shell::escape( array_merge( $cmd, $parameters ) );
2375 }
2376
2377 /**
2378  * wfMerge attempts to merge differences between three texts.
2379  * Returns true for a clean merge and false for failure or a conflict.
2380  *
2381  * @param string $old
2382  * @param string $mine
2383  * @param string $yours
2384  * @param string &$result
2385  * @return bool
2386  */
2387 function wfMerge( $old, $mine, $yours, &$result ) {
2388         global $wgDiff3;
2389
2390         # This check may also protect against code injection in
2391         # case of broken installations.
2392         MediaWiki\suppressWarnings();
2393         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2394         MediaWiki\restoreWarnings();
2395
2396         if ( !$haveDiff3 ) {
2397                 wfDebug( "diff3 not found\n" );
2398                 return false;
2399         }
2400
2401         # Make temporary files
2402         $td = wfTempDir();
2403         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2404         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2405         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2406
2407         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2408         #       a newline character. To avoid this, we normalize the trailing whitespace before
2409         #       creating the diff.
2410
2411         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2412         fclose( $oldtextFile );
2413         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2414         fclose( $mytextFile );
2415         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2416         fclose( $yourtextFile );
2417
2418         # Check for a conflict
2419         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2420                 $oldtextName, $yourtextName );
2421         $handle = popen( $cmd, 'r' );
2422
2423         if ( fgets( $handle, 1024 ) ) {
2424                 $conflict = true;
2425         } else {
2426                 $conflict = false;
2427         }
2428         pclose( $handle );
2429
2430         # Merge differences
2431         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2432                 $oldtextName, $yourtextName );
2433         $handle = popen( $cmd, 'r' );
2434         $result = '';
2435         do {
2436                 $data = fread( $handle, 8192 );
2437                 if ( strlen( $data ) == 0 ) {
2438                         break;
2439                 }
2440                 $result .= $data;
2441         } while ( true );
2442         pclose( $handle );
2443         unlink( $mytextName );
2444         unlink( $oldtextName );
2445         unlink( $yourtextName );
2446
2447         if ( $result === '' && $old !== '' && !$conflict ) {
2448                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2449                 $conflict = true;
2450         }
2451         return !$conflict;
2452 }
2453
2454 /**
2455  * Returns unified plain-text diff of two texts.
2456  * "Useful" for machine processing of diffs.
2457  *
2458  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2459  *
2460  * @param string $before The text before the changes.
2461  * @param string $after The text after the changes.
2462  * @param string $params Command-line options for the diff command.
2463  * @return string Unified diff of $before and $after
2464  */
2465 function wfDiff( $before, $after, $params = '-u' ) {
2466         if ( $before == $after ) {
2467                 return '';
2468         }
2469
2470         global $wgDiff;
2471         MediaWiki\suppressWarnings();
2472         $haveDiff = $wgDiff && file_exists( $wgDiff );
2473         MediaWiki\restoreWarnings();
2474
2475         # This check may also protect against code injection in
2476         # case of broken installations.
2477         if ( !$haveDiff ) {
2478                 wfDebug( "diff executable not found\n" );
2479                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2480                 $format = new UnifiedDiffFormatter();
2481                 return $format->format( $diffs );
2482         }
2483
2484         # Make temporary files
2485         $td = wfTempDir();
2486         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2487         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2488
2489         fwrite( $oldtextFile, $before );
2490         fclose( $oldtextFile );
2491         fwrite( $newtextFile, $after );
2492         fclose( $newtextFile );
2493
2494         // Get the diff of the two files
2495         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2496
2497         $h = popen( $cmd, 'r' );
2498         if ( !$h ) {
2499                 unlink( $oldtextName );
2500                 unlink( $newtextName );
2501                 throw new Exception( __METHOD__ . '(): popen() failed' );
2502         }
2503
2504         $diff = '';
2505
2506         do {
2507                 $data = fread( $h, 8192 );
2508                 if ( strlen( $data ) == 0 ) {
2509                         break;
2510                 }
2511                 $diff .= $data;
2512         } while ( true );
2513
2514         // Clean up
2515         pclose( $h );
2516         unlink( $oldtextName );
2517         unlink( $newtextName );
2518
2519         // Kill the --- and +++ lines. They're not useful.
2520         $diff_lines = explode( "\n", $diff );
2521         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2522                 unset( $diff_lines[0] );
2523         }
2524         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2525                 unset( $diff_lines[1] );
2526         }
2527
2528         $diff = implode( "\n", $diff_lines );
2529
2530         return $diff;
2531 }
2532
2533 /**
2534  * This function works like "use VERSION" in Perl, the program will die with a
2535  * backtrace if the current version of PHP is less than the version provided
2536  *
2537  * This is useful for extensions which due to their nature are not kept in sync
2538  * with releases, and might depend on other versions of PHP than the main code
2539  *
2540  * Note: PHP might die due to parsing errors in some cases before it ever
2541  *       manages to call this function, such is life
2542  *
2543  * @see perldoc -f use
2544  *
2545  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2546  *
2547  * @deprecated since 1.30
2548  *
2549  * @throws MWException
2550  */
2551 function wfUsePHP( $req_ver ) {
2552         $php_ver = PHP_VERSION;
2553
2554         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2555                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2556         }
2557 }
2558
2559 /**
2560  * This function works like "use VERSION" in Perl except it checks the version
2561  * of MediaWiki, the program will die with a backtrace if the current version
2562  * of MediaWiki is less than the version provided.
2563  *
2564  * This is useful for extensions which due to their nature are not kept in sync
2565  * with releases
2566  *
2567  * Note: Due to the behavior of PHP's version_compare() which is used in this
2568  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2569  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2570  * targeted version number. For example if you wanted to allow any variation
2571  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2572  * not result in the same comparison due to the internal logic of
2573  * version_compare().
2574  *
2575  * @see perldoc -f use
2576  *
2577  * @deprecated since 1.26, use the "requires" property of extension.json
2578  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2579  * @throws MWException
2580  */
2581 function wfUseMW( $req_ver ) {
2582         global $wgVersion;
2583
2584         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2585                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2586         }
2587 }
2588
2589 /**
2590  * Return the final portion of a pathname.
2591  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2592  * https://bugs.php.net/bug.php?id=33898
2593  *
2594  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2595  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2596  *
2597  * @param string $path
2598  * @param string $suffix String to remove if present
2599  * @return string
2600  */
2601 function wfBaseName( $path, $suffix = '' ) {
2602         if ( $suffix == '' ) {
2603                 $encSuffix = '';
2604         } else {
2605                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2606         }
2607
2608         $matches = [];
2609         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2610                 return $matches[1];
2611         } else {
2612                 return '';
2613         }
2614 }
2615
2616 /**
2617  * Generate a relative path name to the given file.
2618  * May explode on non-matching case-insensitive paths,
2619  * funky symlinks, etc.
2620  *
2621  * @param string $path Absolute destination path including target filename
2622  * @param string $from Absolute source path, directory only
2623  * @return string
2624  */
2625 function wfRelativePath( $path, $from ) {
2626         // Normalize mixed input on Windows...
2627         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2628         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2629
2630         // Trim trailing slashes -- fix for drive root
2631         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2632         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2633
2634         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2635         $against = explode( DIRECTORY_SEPARATOR, $from );
2636
2637         if ( $pieces[0] !== $against[0] ) {
2638                 // Non-matching Windows drive letters?
2639                 // Return a full path.
2640                 return $path;
2641         }
2642
2643         // Trim off common prefix
2644         while ( count( $pieces ) && count( $against )
2645                 && $pieces[0] == $against[0] ) {
2646                 array_shift( $pieces );
2647                 array_shift( $against );
2648         }
2649
2650         // relative dots to bump us to the parent
2651         while ( count( $against ) ) {
2652                 array_unshift( $pieces, '..' );
2653                 array_shift( $against );
2654         }
2655
2656         array_push( $pieces, wfBaseName( $path ) );
2657
2658         return implode( DIRECTORY_SEPARATOR, $pieces );
2659 }
2660
2661 /**
2662  * Convert an arbitrarily-long digit string from one numeric base
2663  * to another, optionally zero-padding to a minimum column width.
2664  *
2665  * Supports base 2 through 36; digit values 10-36 are represented
2666  * as lowercase letters a-z. Input is case-insensitive.
2667  *
2668  * @deprecated since 1.27 Use Wikimedia\base_convert() directly
2669  *
2670  * @param string $input Input number
2671  * @param int $sourceBase Base of the input number
2672  * @param int $destBase Desired base of the output
2673  * @param int $pad Minimum number of digits in the output (pad with zeroes)
2674  * @param bool $lowercase Whether to output in lowercase or uppercase
2675  * @param string $engine Either "gmp", "bcmath", or "php"
2676  * @return string|bool The output number as a string, or false on error
2677  */
2678 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1,
2679         $lowercase = true, $engine = 'auto'
2680 ) {
2681         return Wikimedia\base_convert( $input, $sourceBase, $destBase, $pad, $lowercase, $engine );
2682 }
2683
2684 /**
2685  * Reset the session id
2686  *
2687  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2688  * @since 1.22
2689  */
2690 function wfResetSessionID() {
2691         wfDeprecated( __FUNCTION__, '1.27' );
2692         $session = SessionManager::getGlobalSession();
2693         $delay = $session->delaySave();
2694
2695         $session->resetId();
2696
2697         // Make sure a session is started, since that's what the old
2698         // wfResetSessionID() did.
2699         if ( session_id() !== $session->getId() ) {
2700                 wfSetupSession( $session->getId() );
2701         }
2702
2703         ScopedCallback::consume( $delay );
2704 }
2705
2706 /**
2707  * Initialise php session
2708  *
2709  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2710  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2711  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2712  *  here), then calling $session->persist().
2713  * @param bool|string $sessionId
2714  */
2715 function wfSetupSession( $sessionId = false ) {
2716         wfDeprecated( __FUNCTION__, '1.27' );
2717
2718         if ( $sessionId ) {
2719                 session_id( $sessionId );
2720         }
2721
2722         $session = SessionManager::getGlobalSession();
2723         $session->persist();
2724
2725         if ( session_id() !== $session->getId() ) {
2726                 session_id( $session->getId() );
2727         }
2728         MediaWiki\quietCall( 'session_start' );
2729 }
2730
2731 /**
2732  * Get an object from the precompiled serialized directory
2733  *
2734  * @param string $name
2735  * @return mixed The variable on success, false on failure
2736  */
2737 function wfGetPrecompiledData( $name ) {
2738         global $IP;
2739
2740         $file = "$IP/serialized/$name";
2741         if ( file_exists( $file ) ) {
2742                 $blob = file_get_contents( $file );
2743                 if ( $blob ) {
2744                         return unserialize( $blob );
2745                 }
2746         }
2747         return false;
2748 }
2749
2750 /**
2751  * Make a cache key for the local wiki.
2752  *
2753  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2754  * @param string $args,...
2755  * @return string
2756  */
2757 function wfMemcKey( /*...*/ ) {
2758         return call_user_func_array(
2759                 [ ObjectCache::getLocalClusterInstance(), 'makeKey' ],
2760                 func_get_args()
2761         );
2762 }
2763
2764 /**
2765  * Make a cache key for a foreign DB.
2766  *
2767  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2768  *
2769  * @param string $db
2770  * @param string $prefix
2771  * @param string $args,...
2772  * @return string
2773  */
2774 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2775         $args = array_slice( func_get_args(), 2 );
2776         $keyspace = $prefix ? "$db-$prefix" : $db;
2777         return call_user_func_array(
2778                 [ ObjectCache::getLocalClusterInstance(), 'makeKeyInternal' ],
2779                 [ $keyspace, $args ]
2780         );
2781 }
2782
2783 /**
2784  * Make a cache key with database-agnostic prefix.
2785  *
2786  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2787  * instead. Must have a prefix as otherwise keys that use a database name
2788  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2789  *
2790  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2791  * @since 1.26
2792  * @param string $args,...
2793  * @return string
2794  */
2795 function wfGlobalCacheKey( /*...*/ ) {
2796         return call_user_func_array(
2797                 [ ObjectCache::getLocalClusterInstance(), 'makeGlobalKey' ],
2798                 func_get_args()
2799         );
2800 }
2801
2802 /**
2803  * Get an ASCII string identifying this wiki
2804  * This is used as a prefix in memcached keys
2805  *
2806  * @return string
2807  */
2808 function wfWikiID() {
2809         global $wgDBprefix, $wgDBname;
2810         if ( $wgDBprefix ) {
2811                 return "$wgDBname-$wgDBprefix";
2812         } else {
2813                 return $wgDBname;
2814         }
2815 }
2816
2817 /**
2818  * Split a wiki ID into DB name and table prefix
2819  *
2820  * @param string $wiki
2821  *
2822  * @return array
2823  */
2824 function wfSplitWikiID( $wiki ) {
2825         $bits = explode( '-', $wiki, 2 );
2826         if ( count( $bits ) < 2 ) {
2827                 $bits[] = '';
2828         }
2829         return $bits;
2830 }
2831
2832 /**
2833  * Get a Database object.
2834  *
2835  * @param int $db Index of the connection to get. May be DB_MASTER for the
2836  *            master (for write queries), DB_REPLICA for potentially lagged read
2837  *            queries, or an integer >= 0 for a particular server.
2838  *
2839  * @param string|string[] $groups Query groups. An array of group names that this query
2840  *                belongs to. May contain a single string if the query is only
2841  *                in one group.
2842  *
2843  * @param string|bool $wiki The wiki ID, or false for the current wiki
2844  *
2845  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2846  * will always return the same object, unless the underlying connection or load
2847  * balancer is manually destroyed.
2848  *
2849  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2850  * updater to ensure that a proper database is being updated.
2851  *
2852  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2853  *       on an injected instance of LoadBalancer.
2854  *
2855  * @return \Wikimedia\Rdbms\Database
2856  */
2857 function wfGetDB( $db, $groups = [], $wiki = false ) {
2858         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2859 }
2860
2861 /**
2862  * Get a load balancer object.
2863  *
2864  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2865  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2866  *
2867  * @param string|bool $wiki Wiki ID, or false for the current wiki
2868  * @return \Wikimedia\Rdbms\LoadBalancer
2869  */
2870 function wfGetLB( $wiki = false ) {
2871         if ( $wiki === false ) {
2872                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2873         } else {
2874                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2875                 return $factory->getMainLB( $wiki );
2876         }
2877 }
2878
2879 /**
2880  * Get the load balancer factory object
2881  *
2882  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2883  *
2884  * @return \Wikimedia\Rdbms\LBFactory
2885  */
2886 function wfGetLBFactory() {
2887         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2888 }
2889
2890 /**
2891  * Find a file.
2892  * Shortcut for RepoGroup::singleton()->findFile()
2893  *
2894  * @param string $title String or Title object
2895  * @param array $options Associative array of options (see RepoGroup::findFile)
2896  * @return File|bool File, or false if the file does not exist
2897  */
2898 function wfFindFile( $title, $options = [] ) {
2899         return RepoGroup::singleton()->findFile( $title, $options );
2900 }
2901
2902 /**
2903  * Get an object referring to a locally registered file.
2904  * Returns a valid placeholder object if the file does not exist.
2905  *
2906  * @param Title|string $title
2907  * @return LocalFile|null A File, or null if passed an invalid Title
2908  */
2909 function wfLocalFile( $title ) {
2910         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2911 }
2912
2913 /**
2914  * Should low-performance queries be disabled?
2915  *
2916  * @return bool
2917  * @codeCoverageIgnore
2918  */
2919 function wfQueriesMustScale() {
2920         global $wgMiserMode;
2921         return $wgMiserMode
2922                 || ( SiteStats::pages() > 100000
2923                 && SiteStats::edits() > 1000000
2924                 && SiteStats::users() > 10000 );
2925 }
2926
2927 /**
2928  * Get the path to a specified script file, respecting file
2929  * extensions; this is a wrapper around $wgScriptPath etc.
2930  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2931  *
2932  * @param string $script Script filename, sans extension
2933  * @return string
2934  */
2935 function wfScript( $script = 'index' ) {
2936         global $wgScriptPath, $wgScript, $wgLoadScript;
2937         if ( $script === 'index' ) {
2938                 return $wgScript;
2939         } elseif ( $script === 'load' ) {
2940                 return $wgLoadScript;
2941         } else {
2942                 return "{$wgScriptPath}/{$script}.php";
2943         }
2944 }
2945
2946 /**
2947  * Get the script URL.
2948  *
2949  * @return string Script URL
2950  */
2951 function wfGetScriptUrl() {
2952         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2953                 /* as it was called, minus the query string.
2954                  *
2955                  * Some sites use Apache rewrite rules to handle subdomains,
2956                  * and have PHP set up in a weird way that causes PHP_SELF
2957                  * to contain the rewritten URL instead of the one that the
2958                  * outside world sees.
2959                  *
2960                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2961                  * provides containing the "before" URL.
2962                  */
2963                 return $_SERVER['SCRIPT_NAME'];
2964         } else {
2965                 return $_SERVER['URL'];
2966         }
2967 }
2968
2969 /**
2970  * Convenience function converts boolean values into "true"
2971  * or "false" (string) values
2972  *
2973  * @param bool $value
2974  * @return string
2975  */
2976 function wfBoolToStr( $value ) {
2977         return $value ? 'true' : 'false';
2978 }
2979
2980 /**
2981  * Get a platform-independent path to the null file, e.g. /dev/null
2982  *
2983  * @return string
2984  */
2985 function wfGetNull() {
2986         return wfIsWindows() ? 'NUL' : '/dev/null';
2987 }
2988
2989 /**
2990  * Waits for the replica DBs to catch up to the master position
2991  *
2992  * Use this when updating very large numbers of rows, as in maintenance scripts,
2993  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2994  *
2995  * By default this waits on the main DB cluster of the current wiki.
2996  * If $cluster is set to "*" it will wait on all DB clusters, including
2997  * external ones. If the lag being waiting on is caused by the code that
2998  * does this check, it makes since to use $ifWritesSince, particularly if
2999  * cluster is "*", to avoid excess overhead.
3000  *
3001  * Never call this function after a big DB write that is still in a transaction.
3002  * This only makes sense after the possible lag inducing changes were committed.
3003  *
3004  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
3005  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
3006  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
3007  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
3008  * @return bool Success (able to connect and no timeouts reached)
3009  * @deprecated since 1.27 Use LBFactory::waitForReplication
3010  */
3011 function wfWaitForSlaves(
3012         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3013 ) {
3014         if ( $timeout === null ) {
3015                 $timeout = ( PHP_SAPI === 'cli' ) ? 86400 : 10;
3016         }
3017
3018         if ( $cluster === '*' ) {
3019                 $cluster = false;
3020                 $wiki = false;
3021         } elseif ( $wiki === false ) {
3022                 $wiki = wfWikiID();
3023         }
3024
3025         try {
3026                 wfGetLBFactory()->waitForReplication( [
3027                         'wiki' => $wiki,
3028                         'cluster' => $cluster,
3029                         'timeout' => $timeout,
3030                         // B/C: first argument used to be "max seconds of lag"; ignore such values
3031                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
3032                 ] );
3033         } catch ( DBReplicationWaitError $e ) {
3034                 return false;
3035         }
3036
3037         return true;
3038 }
3039
3040 /**
3041  * Count down from $seconds to zero on the terminal, with a one-second pause
3042  * between showing each number. For use in command-line scripts.
3043  *
3044  * @codeCoverageIgnore
3045  * @param int $seconds
3046  */
3047 function wfCountDown( $seconds ) {
3048         for ( $i = $seconds; $i >= 0; $i-- ) {
3049                 if ( $i != $seconds ) {
3050                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3051                 }
3052                 echo $i;
3053                 flush();
3054                 if ( $i ) {
3055                         sleep( 1 );
3056                 }
3057         }
3058         echo "\n";
3059 }
3060
3061 /**
3062  * Replace all invalid characters with '-'.
3063  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3064  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3065  *
3066  * @param string $name Filename to process
3067  * @return string
3068  */
3069 function wfStripIllegalFilenameChars( $name ) {
3070         global $wgIllegalFileChars;
3071         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3072         $name = preg_replace(
3073                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3074                 '-',
3075                 $name
3076         );
3077         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3078         $name = wfBaseName( $name );
3079         return $name;
3080 }
3081
3082 /**
3083  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3084  *
3085  * @return int Resulting value of the memory limit.
3086  */
3087 function wfMemoryLimit() {
3088         global $wgMemoryLimit;
3089         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3090         if ( $memlimit != -1 ) {
3091                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3092                 if ( $conflimit == -1 ) {
3093                         wfDebug( "Removing PHP's memory limit\n" );
3094                         MediaWiki\suppressWarnings();
3095                         ini_set( 'memory_limit', $conflimit );
3096                         MediaWiki\restoreWarnings();
3097                         return $conflimit;
3098                 } elseif ( $conflimit > $memlimit ) {
3099                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3100                         MediaWiki\suppressWarnings();
3101                         ini_set( 'memory_limit', $conflimit );
3102                         MediaWiki\restoreWarnings();
3103                         return $conflimit;
3104                 }
3105         }
3106         return $memlimit;
3107 }
3108
3109 /**
3110  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3111  *
3112  * @return int Prior time limit
3113  * @since 1.26
3114  */
3115 function wfTransactionalTimeLimit() {
3116         global $wgTransactionalTimeLimit;
3117
3118         $timeLimit = ini_get( 'max_execution_time' );
3119         // Note that CLI scripts use 0
3120         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3121                 set_time_limit( $wgTransactionalTimeLimit );
3122         }
3123
3124         ignore_user_abort( true ); // ignore client disconnects
3125
3126         return $timeLimit;
3127 }
3128
3129 /**
3130  * Converts shorthand byte notation to integer form
3131  *
3132  * @param string $string
3133  * @param int $default Returned if $string is empty
3134  * @return int
3135  */
3136 function wfShorthandToInteger( $string = '', $default = -1 ) {
3137         $string = trim( $string );
3138         if ( $string === '' ) {
3139                 return $default;
3140         }
3141         $last = $string[strlen( $string ) - 1];
3142         $val = intval( $string );
3143         switch ( $last ) {
3144                 case 'g':
3145                 case 'G':
3146                         $val *= 1024;
3147                         // break intentionally missing
3148                 case 'm':
3149                 case 'M':
3150                         $val *= 1024;
3151                         // break intentionally missing
3152                 case 'k':
3153                 case 'K':
3154                         $val *= 1024;
3155         }
3156
3157         return $val;
3158 }
3159
3160 /**
3161  * Get the normalised IETF language tag
3162  * See unit test for examples.
3163  *
3164  * @param string $code The language code.
3165  * @return string The language code which complying with BCP 47 standards.
3166  */
3167 function wfBCP47( $code ) {
3168         $codeSegment = explode( '-', $code );
3169         $codeBCP = [];
3170         foreach ( $codeSegment as $segNo => $seg ) {
3171                 // when previous segment is x, it is a private segment and should be lc
3172                 if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3173                         $codeBCP[$segNo] = strtolower( $seg );
3174                 // ISO 3166 country code
3175                 } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3176                         $codeBCP[$segNo] = strtoupper( $seg );
3177                 // ISO 15924 script code
3178                 } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3179                         $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3180                 // Use lowercase for other cases
3181                 } else {
3182                         $codeBCP[$segNo] = strtolower( $seg );
3183                 }
3184         }
3185         $langCode = implode( '-', $codeBCP );
3186         return $langCode;
3187 }
3188
3189 /**
3190  * Get a specific cache object.
3191  *
3192  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3193  * @return BagOStuff
3194  */
3195 function wfGetCache( $cacheType ) {
3196         return ObjectCache::getInstance( $cacheType );
3197 }
3198
3199 /**
3200  * Get the main cache object
3201  *
3202  * @return BagOStuff
3203  */
3204 function wfGetMainCache() {
3205         global $wgMainCacheType;
3206         return ObjectCache::getInstance( $wgMainCacheType );
3207 }
3208
3209 /**
3210  * Get the cache object used by the message cache
3211  *
3212  * @return BagOStuff
3213  */
3214 function wfGetMessageCacheStorage() {
3215         global $wgMessageCacheType;
3216         return ObjectCache::getInstance( $wgMessageCacheType );
3217 }
3218
3219 /**
3220  * Get the cache object used by the parser cache
3221  *
3222  * @deprecated since 1.30, use MediaWikiServices::getParserCache()->getCacheStorage()
3223  * @return BagOStuff
3224  */
3225 function wfGetParserCacheStorage() {
3226         global $wgParserCacheType;
3227         return ObjectCache::getInstance( $wgParserCacheType );
3228 }
3229
3230 /**
3231  * Call hook functions defined in $wgHooks
3232  *
3233  * @param string $event Event name
3234  * @param array $args Parameters passed to hook functions
3235  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3236  *
3237  * @return bool True if no handler aborted the hook
3238  * @deprecated since 1.25 - use Hooks::run
3239  */
3240 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3241         return Hooks::run( $event, $args, $deprecatedVersion );
3242 }
3243
3244 /**
3245  * Wrapper around php's unpack.
3246  *
3247  * @param string $format The format string (See php's docs)
3248  * @param string $data A binary string of binary data
3249  * @param int|bool $length The minimum length of $data or false. This is to
3250  *      prevent reading beyond the end of $data. false to disable the check.
3251  *
3252  * Also be careful when using this function to read unsigned 32 bit integer
3253  * because php might make it negative.
3254  *
3255  * @throws MWException If $data not long enough, or if unpack fails
3256  * @return array Associative array of the extracted data
3257  */
3258 function wfUnpack( $format, $data, $length = false ) {
3259         if ( $length !== false ) {
3260                 $realLen = strlen( $data );
3261                 if ( $realLen < $length ) {
3262                         throw new MWException( "Tried to use wfUnpack on a "
3263                                 . "string of length $realLen, but needed one "
3264                                 . "of at least length $length."
3265                         );
3266                 }
3267         }
3268
3269         MediaWiki\suppressWarnings();
3270         $result = unpack( $format, $data );
3271         MediaWiki\restoreWarnings();
3272
3273         if ( $result === false ) {
3274                 // If it cannot extract the packed data.
3275                 throw new MWException( "unpack could not unpack binary data" );
3276         }
3277         return $result;
3278 }
3279
3280 /**
3281  * Determine if an image exists on the 'bad image list'.
3282  *
3283  * The format of MediaWiki:Bad_image_list is as follows:
3284  *    * Only list items (lines starting with "*") are considered
3285  *    * The first link on a line must be a link to a bad image
3286  *    * Any subsequent links on the same line are considered to be exceptions,
3287  *      i.e. articles where the image may occur inline.
3288  *
3289  * @param string $name The image name to check
3290  * @param Title|bool $contextTitle The page on which the image occurs, if known
3291  * @param string $blacklist Wikitext of a file blacklist
3292  * @return bool
3293  */
3294 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3295         # Handle redirects; callers almost always hit wfFindFile() anyway,
3296         # so just use that method because it has a fast process cache.
3297         $file = wfFindFile( $name ); // get the final name
3298         $name = $file ? $file->getTitle()->getDBkey() : $name;
3299
3300         # Run the extension hook
3301         $bad = false;
3302         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3303                 return (bool)$bad;
3304         }
3305
3306         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3307         $key = $cache->makeKey(
3308                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3309         );
3310         $badImages = $cache->get( $key );
3311
3312         if ( $badImages === false ) { // cache miss
3313                 if ( $blacklist === null ) {
3314                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3315                 }
3316                 # Build the list now
3317                 $badImages = [];
3318                 $lines = explode( "\n", $blacklist );
3319                 foreach ( $lines as $line ) {
3320                         # List items only
3321                         if ( substr( $line, 0, 1 ) !== '*' ) {
3322                                 continue;
3323                         }
3324
3325                         # Find all links
3326                         $m = [];
3327                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3328                                 continue;
3329                         }
3330
3331                         $exceptions = [];
3332                         $imageDBkey = false;
3333                         foreach ( $m[1] as $i => $titleText ) {
3334                                 $title = Title::newFromText( $titleText );
3335                                 if ( !is_null( $title ) ) {
3336                                         if ( $i == 0 ) {
3337                                                 $imageDBkey = $title->getDBkey();
3338                                         } else {
3339                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3340                                         }
3341                                 }
3342                         }
3343
3344                         if ( $imageDBkey !== false ) {
3345                                 $badImages[$imageDBkey] = $exceptions;
3346                         }
3347                 }
3348                 $cache->set( $key, $badImages, 60 );
3349         }
3350
3351         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3352         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3353
3354         return $bad;
3355 }
3356
3357 /**
3358  * Determine whether the client at a given source IP is likely to be able to
3359  * access the wiki via HTTPS.
3360  *
3361  * @param string $ip The IPv4/6 address in the normal human-readable form
3362  * @return bool
3363  */
3364 function wfCanIPUseHTTPS( $ip ) {
3365         $canDo = true;
3366         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3367         return !!$canDo;
3368 }
3369
3370 /**
3371  * Determine input string is represents as infinity
3372  *
3373  * @param string $str The string to determine
3374  * @return bool
3375  * @since 1.25
3376  */
3377 function wfIsInfinity( $str ) {
3378         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3379         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3380         return in_array( $str, $infinityValues );
3381 }
3382
3383 /**
3384  * Returns true if these thumbnail parameters match one that MediaWiki
3385  * requests from file description pages and/or parser output.
3386  *
3387  * $params is considered non-standard if they involve a non-standard
3388  * width or any non-default parameters aside from width and page number.
3389  * The number of possible files with standard parameters is far less than
3390  * that of all combinations; rate-limiting for them can thus be more generious.
3391  *
3392  * @param File $file
3393  * @param array $params
3394  * @return bool
3395  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3396  */
3397 function wfThumbIsStandard( File $file, array $params ) {
3398         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3399
3400         $multipliers = [ 1 ];
3401         if ( $wgResponsiveImages ) {
3402                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3403                 // @see Linker::processResponsiveImages
3404                 $multipliers[] = 1.5;
3405                 $multipliers[] = 2;
3406         }
3407
3408         $handler = $file->getHandler();
3409         if ( !$handler || !isset( $params['width'] ) ) {
3410                 return false;
3411         }
3412
3413         $basicParams = [];
3414         if ( isset( $params['page'] ) ) {
3415                 $basicParams['page'] = $params['page'];
3416         }
3417
3418         $thumbLimits = [];
3419         $imageLimits = [];
3420         // Expand limits to account for multipliers
3421         foreach ( $multipliers as $multiplier ) {
3422                 $thumbLimits = array_merge( $thumbLimits, array_map(
3423                         function ( $width ) use ( $multiplier ) {
3424                                 return round( $width * $multiplier );
3425                         }, $wgThumbLimits )
3426                 );
3427                 $imageLimits = array_merge( $imageLimits, array_map(
3428                         function ( $pair ) use ( $multiplier ) {
3429                                 return [
3430                                         round( $pair[0] * $multiplier ),
3431                                         round( $pair[1] * $multiplier ),
3432                                 ];
3433                         }, $wgImageLimits )
3434                 );
3435         }
3436
3437         // Check if the width matches one of $wgThumbLimits
3438         if ( in_array( $params['width'], $thumbLimits ) ) {
3439                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3440                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3441                 $handler->normaliseParams( $file, $normalParams );
3442         } else {
3443                 // If not, then check if the width matchs one of $wgImageLimits
3444                 $match = false;
3445                 foreach ( $imageLimits as $pair ) {
3446                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3447                         // Decide whether the thumbnail should be scaled on width or height.
3448                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3449                         $handler->normaliseParams( $file, $normalParams );
3450                         // Check if this standard thumbnail size maps to the given width
3451                         if ( $normalParams['width'] == $params['width'] ) {
3452                                 $match = true;
3453                                 break;
3454                         }
3455                 }
3456                 if ( !$match ) {
3457                         return false; // not standard for description pages
3458                 }
3459         }
3460
3461         // Check that the given values for non-page, non-width, params are just defaults
3462         foreach ( $params as $key => $value ) {
3463                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3464                         return false;
3465                 }
3466         }
3467
3468         return true;
3469 }
3470
3471 /**
3472  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3473  *
3474  * Values that exist in both values will be combined with += (all values of the array
3475  * of $newValues will be added to the values of the array of $baseArray, while values,
3476  * that exists in both, the value of $baseArray will be used).
3477  *
3478  * @param array $baseArray The array where you want to add the values of $newValues to
3479  * @param array $newValues An array with new values
3480  * @return array The combined array
3481  * @since 1.26
3482  */
3483 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3484         // First merge items that are in both arrays
3485         foreach ( $baseArray as $name => &$groupVal ) {
3486                 if ( isset( $newValues[$name] ) ) {
3487                         $groupVal += $newValues[$name];
3488                 }
3489         }
3490         // Now add items that didn't exist yet
3491         $baseArray += $newValues;
3492
3493         return $baseArray;
3494 }