Followup r81034, remove the global statements

[mediawiki.git] / includes / WebRequest.php

<?php
/**
 * Deal with importing all those nasssty globals and things
 *
 * Copyright © 2003 Brion Vibber <brion@pobox.com>
 * http://www.mediawiki.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * The WebRequest class encapsulates getting at data passed in the
 * URL or via a POSTed form, handling remove of "magic quotes" slashes,
 * stripping illegal input characters and normalizing Unicode sequences.
 *
 * Usually this is used via a global singleton, $wgRequest. You should
 * not create a second WebRequest object; make a FauxRequest object if
 * you want to pass arbitrary data to some function in place of the web
 * input.
 *
 * @ingroup HTTP
 */
class WebRequest {
        protected $data, $headers = array();

        /**
         * Lazy-init response object
         * @var WebResponse
         */
        private $response;

        public function __construct() {
                /// @todo Fixme: this preemptive de-quoting can interfere with other web libraries
                ///        and increases our memory footprint. It would be cleaner to do on
                ///        demand; but currently we have no wrapper for $_SERVER etc.
                $this->checkMagicQuotes();

                // POST overrides GET data
                // We don't use $_REQUEST here to avoid interference from cookies...
                $this->data = $_POST + $_GET;
        }

        /**
         * Check for title, action, and/or variant data in the URL
         * and interpolate it into the GET variables.
         * This should only be run after $wgContLang is available,
         * as we may need the list of language variants to determine
         * available variant URLs.
         */
        public function interpolateTitle() {
                global $wgUsePathInfo;

                // bug 16019: title interpolation on API queries is useless and sometimes harmful
                if ( defined( 'MW_API' ) ) {
                        return;
                }

                if ( $wgUsePathInfo ) {
                        // PATH_INFO is mangled due to http://bugs.php.net/bug.php?id=31892
                        // And also by Apache 2.x, double slashes are converted to single slashes.
                        // So we will use REQUEST_URI if possible.
                        $matches = array();

                        if ( !empty( $_SERVER['REQUEST_URI'] ) ) {
                                // Slurp out the path portion to examine...
                                $url = $_SERVER['REQUEST_URI'];
                                if ( !preg_match( '!^https?://!', $url ) ) {
                                        $url = 'http://unused' . $url;
                                }
                                $a = parse_url( $url );
                                if( $a ) {
                                        $path = isset( $a['path'] ) ? $a['path'] : '';

                                        global $wgScript;
                                        if( $path == $wgScript ) {
                                                // Script inside a rewrite path?
                                                // Abort to keep from breaking...
                                                return;
                                        }
                                        // Raw PATH_INFO style
                                        $matches = $this->extractTitle( $path, "$wgScript/$1" );

                                        global $wgArticlePath;
                                        if( !$matches && $wgArticlePath ) {
                                                $matches = $this->extractTitle( $path, $wgArticlePath );
                                        }

                                        global $wgActionPaths;
                                        if( !$matches && $wgActionPaths ) {
                                                $matches = $this->extractTitle( $path, $wgActionPaths, 'action' );
                                        }

                                        global $wgVariantArticlePath, $wgContLang;
                                        if( !$matches && $wgVariantArticlePath ) {
                                                $variantPaths = array();
                                                foreach( $wgContLang->getVariants() as $variant ) {
                                                        $variantPaths[$variant] =
                                                                str_replace( '$2', $variant, $wgVariantArticlePath );
                                                }
                                                $matches = $this->extractTitle( $path, $variantPaths, 'variant' );
                                        }
                                }
                        } elseif ( isset( $_SERVER['ORIG_PATH_INFO'] ) && $_SERVER['ORIG_PATH_INFO'] != '' ) {
                                // Mangled PATH_INFO
                                // http://bugs.php.net/bug.php?id=31892
                                // Also reported when ini_get('cgi.fix_pathinfo')==false
                                $matches['title'] = substr( $_SERVER['ORIG_PATH_INFO'], 1 );

                        } elseif ( isset( $_SERVER['PATH_INFO'] ) && ($_SERVER['PATH_INFO'] != '') ) {
                                // Regular old PATH_INFO yay
                                $matches['title'] = substr( $_SERVER['PATH_INFO'], 1 );
                        }
                        foreach( $matches as $key => $val) {
                                $this->data[$key] = $_GET[$key] = $_REQUEST[$key] = $val;
                        }
                }
        }

        /**
         * Internal URL rewriting function; tries to extract page title and,
         * optionally, one other fixed parameter value from a URL path.
         *
         * @param $path string: the URL path given from the client
         * @param $bases array: one or more URLs, optionally with $1 at the end
         * @param $key string: if provided, the matching key in $bases will be
         *             passed on as the value of this URL parameter
         * @return array of URL variables to interpolate; empty if no match
         */
        private function extractTitle( $path, $bases, $key=false ) {
                foreach( (array)$bases as $keyValue => $base ) {
                        // Find the part after $wgArticlePath
                        $base = str_replace( '$1', '', $base );
                        $baseLen = strlen( $base );
                        if( substr( $path, 0, $baseLen ) == $base ) {
                                $raw = substr( $path, $baseLen );
                                if( $raw !== '' ) {
                                        $matches = array( 'title' => rawurldecode( $raw ) );
                                        if( $key ) {
                                                $matches[$key] = $keyValue;
                                        }
                                        return $matches;
                                }
                        }
                }
                return array();
        }

        /**
         * Recursively strips slashes from the given array;
         * used for undoing the evil that is magic_quotes_gpc.
         *
         * @param $arr array: will be modified
         * @return array the original array
         */
        private function &fix_magic_quotes( &$arr ) {
                foreach( $arr as $key => $val ) {
                        if( is_array( $val ) ) {
                                $this->fix_magic_quotes( $arr[$key] );
                        } else {
                                $arr[$key] = stripslashes( $val );
                        }
                }
                return $arr;
        }

        /**
         * If magic_quotes_gpc option is on, run the global arrays
         * through fix_magic_quotes to strip out the stupid slashes.
         * WARNING: This should only be done once! Running a second
         * time could damage the values.
         */
        private function checkMagicQuotes() {
                $mustFixQuotes = function_exists( 'get_magic_quotes_gpc' )
                        && get_magic_quotes_gpc();
                if( $mustFixQuotes ) {
                        $this->fix_magic_quotes( $_COOKIE );
                        $this->fix_magic_quotes( $_ENV );
                        $this->fix_magic_quotes( $_GET );
                        $this->fix_magic_quotes( $_POST );
                        $this->fix_magic_quotes( $_REQUEST );
                        $this->fix_magic_quotes( $_SERVER );
                }
        }

        /**
         * Recursively normalizes UTF-8 strings in the given array.
         *
         * @param $data string or array
         * @return cleaned-up version of the given
         * @private
         */
        function normalizeUnicode( $data ) {
                if( is_array( $data ) ) {
                        foreach( $data as $key => $val ) {
                                $data[$key] = $this->normalizeUnicode( $val );
                        }
                } else {
                        global $wgContLang;
                        $data = $wgContLang->normalize( $data );
                }
                return $data;
        }

        /**
         * Fetch a value from the given array or return $default if it's not set.
         *
         * @param $arr Array
         * @param $name String
         * @param $default Mixed
         * @return mixed
         */
        private function getGPCVal( $arr, $name, $default ) {
                # PHP is so nice to not touch input data, except sometimes:
                # http://us2.php.net/variables.external#language.variables.external.dot-in-names
                # Work around PHP *feature* to avoid *bugs* elsewhere.
                $name = strtr( $name, '.', '_' );
                if( isset( $arr[$name] ) ) {
                        global $wgContLang;
                        $data = $arr[$name];
                        if( isset( $_GET[$name] ) && !is_array( $data ) ) {
                                # Check for alternate/legacy character encoding.
                                if( isset( $wgContLang ) ) {
                                        $data = $wgContLang->checkTitleEncoding( $data );
                                }
                        }
                        $data = $this->normalizeUnicode( $data );
                        return $data;
                } else {
                        taint( $default );
                        return $default;
                }
        }

        /**
         * Fetch a scalar from the input or return $default if it's not set.
         * Returns a string. Arrays are discarded. Useful for
         * non-freeform text inputs (e.g. predefined internal text keys
         * selected by a drop-down menu). For freeform input, see getText().
         *
         * @param $name String
         * @param $default String: optional default (or NULL)
         * @return String
         */
        public function getVal( $name, $default = null ) {
                $val = $this->getGPCVal( $this->data, $name, $default );
                if( is_array( $val ) ) {
                        $val = $default;
                }
                if( is_null( $val ) ) {
                        return $val;
                } else {
                        return (string)$val;
                }
        }

        /**
         * Set an aribtrary value into our get/post data.
         *
         * @param $key String: key name to use
         * @param $value Mixed: value to set
         * @return Mixed: old value if one was present, null otherwise
         */
        public function setVal( $key, $value ) {
                $ret = isset( $this->data[$key] ) ? $this->data[$key] : null;
                $this->data[$key] = $value;
                return $ret;
        }

        /**
         * Fetch an array from the input or return $default if it's not set.
         * If source was scalar, will return an array with a single element.
         * If no source and no default, returns NULL.
         *
         * @param $name String
         * @param $default Array: optional default (or NULL)
         * @return Array
         */
        public function getArray( $name, $default = null ) {
                $val = $this->getGPCVal( $this->data, $name, $default );
                if( is_null( $val ) ) {
                        return null;
                } else {
                        return (array)$val;
                }
        }

        /**
         * Fetch an array of integers, or return $default if it's not set.
         * If source was scalar, will return an array with a single element.
         * If no source and no default, returns NULL.
         * If an array is returned, contents are guaranteed to be integers.
         *
         * @param $name String
         * @param $default Array: option default (or NULL)
         * @return Array of ints
         */
        public function getIntArray( $name, $default = null ) {
                $val = $this->getArray( $name, $default );
                if( is_array( $val ) ) {
                        $val = array_map( 'intval', $val );
                }
                return $val;
        }

        /**
         * Fetch an integer value from the input or return $default if not set.
         * Guaranteed to return an integer; non-numeric input will typically
         * return 0.
         *
         * @param $name String
         * @param $default Integer
         * @return Integer
         */
        public function getInt( $name, $default = 0 ) {
                return intval( $this->getVal( $name, $default ) );
        }

        /**
         * Fetch an integer value from the input or return null if empty.
         * Guaranteed to return an integer or null; non-numeric input will
         * typically return null.
         *
         * @param $name String
         * @return Integer
         */
        public function getIntOrNull( $name ) {
                $val = $this->getVal( $name );
                return is_numeric( $val )
                        ? intval( $val )
                        : null;
        }

        /**
         * Fetch a boolean value from the input or return $default if not set.
         * Guaranteed to return true or false, with normal PHP semantics for
         * boolean interpretation of strings.
         *
         * @param $name String
         * @param $default Boolean
         * @return Boolean
         */
        public function getBool( $name, $default = false ) {
                return (bool)$this->getVal( $name, $default );
        }
        
        /**
         * Fetch a boolean value from the input or return $default if not set.
         * Unlike getBool, the string "false" will result in boolean false, which is
         * useful when interpreting information sent from JavaScript.
         *
         * @param $name String
         * @param $default Boolean
         * @return Boolean
         */
        public function getFuzzyBool( $name, $default = false ) {
                return $this->getBool( $name, $default ) && strcasecmp( $this->getVal( $name ), 'false' ) !== 0;
        }

        /**
         * Return true if the named value is set in the input, whatever that
         * value is (even "0"). Return false if the named value is not set.
         * Example use is checking for the presence of check boxes in forms.
         *
         * @param $name String
         * @return Boolean
         */
        public function getCheck( $name ) {
                # Checkboxes and buttons are only present when clicked
                # Presence connotes truth, abscense false
                $val = $this->getVal( $name, null );
                return isset( $val );
        }

        /**
         * Fetch a text string from the given array or return $default if it's not
         * set. Carriage returns are stripped from the text, and with some language
         * modules there is an input transliteration applied. This should generally
         * be used for form <textarea> and <input> fields. Used for user-supplied
         * freeform text input (for which input transformations may be required - e.g.
         * Esperanto x-coding).
         *
         * @param $name String
         * @param $default String: optional
         * @return String
         */
        public function getText( $name, $default = '' ) {
                global $wgContLang;
                $val = $this->getVal( $name, $default );
                return str_replace( "\r\n", "\n",
                        $wgContLang->recodeInput( $val ) );
        }

        /**
         * Extracts the given named values into an array.
         * If no arguments are given, returns all input values.
         * No transformation is performed on the values.
         */
        public function getValues() {
                $names = func_get_args();
                if ( count( $names ) == 0 ) {
                        $names = array_keys( $this->data );
                }

                $retVal = array();
                foreach ( $names as $name ) {
                        $value = $this->getVal( $name );
                        if ( !is_null( $value ) ) {
                                $retVal[$name] = $value;
                        }
                }
                return $retVal;
        }

        /**
         * Returns true if the present request was reached by a POST operation,
         * false otherwise (GET, HEAD, or command-line).
         *
         * Note that values retrieved by the object may come from the
         * GET URL etc even on a POST request.
         *
         * @return Boolean
         */
        public function wasPosted() {
                return $_SERVER['REQUEST_METHOD'] == 'POST';
        }

        /**
         * Returns true if there is a session cookie set.
         * This does not necessarily mean that the user is logged in!
         *
         * If you want to check for an open session, use session_id()
         * instead; that will also tell you if the session was opened
         * during the current request (in which case the cookie will
         * be sent back to the client at the end of the script run).
         *
         * @return Boolean
         */
        public function checkSessionCookie() {
                return isset( $_COOKIE[ session_name() ] );
        }

        /**
         * Get a cookie from the $_COOKIE jar
         *
         * @param $key String: the name of the cookie
         * @param $prefix String: a prefix to use for the cookie name, if not $wgCookiePrefix
         * @param $default Mixed: what to return if the value isn't found
         * @return Mixed: cookie value or $default if the cookie not set
         */
        public function getCookie( $key, $prefix = null, $default = null ) {
                if( $prefix === null ) {
                        global $wgCookiePrefix;
                        $prefix = $wgCookiePrefix;
                }
                return $this->getGPCVal( $_COOKIE, $prefix . $key , $default );
        }

        /**
         * Return the path portion of the request URI.
         *
         * @return String
         */
        public function getRequestURL() {
                if( isset( $_SERVER['REQUEST_URI']) && strlen($_SERVER['REQUEST_URI']) ) {
                        $base = $_SERVER['REQUEST_URI'];
                } elseif( isset( $_SERVER['SCRIPT_NAME'] ) ) {
                        // Probably IIS; doesn't set REQUEST_URI
                        $base = $_SERVER['SCRIPT_NAME'];
                        if( isset( $_SERVER['QUERY_STRING'] ) && $_SERVER['QUERY_STRING'] != '' ) {
                                $base .= '?' . $_SERVER['QUERY_STRING'];
                        }
                } else {
                        // This shouldn't happen!
                        throw new MWException( "Web server doesn't provide either " .
                                "REQUEST_URI or SCRIPT_NAME. Report details of your " .
                                "web server configuration to http://bugzilla.wikimedia.org/" );
                }
                // User-agents should not send a fragment with the URI, but
                // if they do, and the web server passes it on to us, we
                // need to strip it or we get false-positive redirect loops
                // or weird output URLs
                $hash = strpos( $base, '#' );
                if( $hash !== false ) {
                        $base = substr( $base, 0, $hash );
                }
                if( $base{0} == '/' ) {
                        return $base;
                } else {
                        // We may get paths with a host prepended; strip it.
                        return preg_replace( '!^[^:]+://[^/]+/!', '/', $base );
                }
        }

        /**
         * Return the request URI with the canonical service and hostname.
         *
         * @return String
         */
        public function getFullRequestURL() {
                global $wgServer;
                return $wgServer . $this->getRequestURL();
        }

        /**
         * Take an arbitrary query and rewrite the present URL to include it
         * @param $query String: query string fragment; do not include initial '?'
         *
         * @return String
         */
        public function appendQuery( $query ) {
                global $wgTitle;
                $basequery = '';
                foreach( $_GET as $var => $val ) {
                        if ( $var == 'title' ) {
                                continue;
                        }
                        if ( is_array( $val ) ) {
                                /* This will happen given a request like
                                 * http://en.wikipedia.org/w/index.php?title[]=Special:Userlogin&returnto[]=Main_Page
                                 */
                                continue;
                        }
                        $basequery .= '&' . urlencode( $var ) . '=' . urlencode( $val );
                }
                $basequery .= '&' . $query;

                # Trim the extra &
                $basequery = substr( $basequery, 1 );
                return $wgTitle->getLocalURL( $basequery );
        }

        /**
         * HTML-safe version of appendQuery().
         *
         * @param $query String: query string fragment; do not include initial '?'
         * @return String
         */
        public function escapeAppendQuery( $query ) {
                return htmlspecialchars( $this->appendQuery( $query ) );
        }

        public function appendQueryValue( $key, $value, $onlyquery = false ) {
                return $this->appendQueryArray( array( $key => $value ), $onlyquery );
        }

        /**
         * Appends or replaces value of query variables.
         *
         * @param $array Array of values to replace/add to query
         * @param $onlyquery Bool: whether to only return the query string and not
         *                   the complete URL
         * @return String
         */
        public function appendQueryArray( $array, $onlyquery = false ) {
                global $wgTitle;
                $newquery = $_GET;
                unset( $newquery['title'] );
                $newquery = array_merge( $newquery, $array );
                $query = wfArrayToCGI( $newquery );
                return $onlyquery ? $query : $wgTitle->getLocalURL( $query );
        }

        /**
         * Check for limit and offset parameters on the input, and return sensible
         * defaults if not given. The limit must be positive and is capped at 5000.
         * Offset must be positive but is not capped.
         *
         * @param $deflimit Integer: limit to use if no input and the user hasn't set the option.
         * @param $optionname String: to specify an option other than rclimit to pull from.
         * @return array first element is limit, second is offset
         */
        public function getLimitOffset( $deflimit = 50, $optionname = 'rclimit' ) {
                global $wgUser;

                $limit = $this->getInt( 'limit', 0 );
                if( $limit < 0 ) {
                        $limit = 0;
                }
                if( ( $limit == 0 ) && ( $optionname != '' ) ) {
                        $limit = (int)$wgUser->getOption( $optionname );
                }
                if( $limit <= 0 ) {
                        $limit = $deflimit;
                }
                if( $limit > 5000 ) {
                        $limit = 5000; # We have *some* limits...
                }

                $offset = $this->getInt( 'offset', 0 );
                if( $offset < 0 ) {
                        $offset = 0;
                }

                return array( $limit, $offset );
        }

        /**
         * Return the path to the temporary file where PHP has stored the upload.
         *
         * @param $key String:
         * @return string or NULL if no such file.
         */
        public function getFileTempname( $key ) {
                $file = new WebRequestUpload( $this, $key );
                return $file->getTempName();
        }

        /**
         * Return the size of the upload, or 0.
         *
         * @deprecated
         * @param $key String:
         * @return integer
         */
        public function getFileSize( $key ) {
                $file = new WebRequestUpload( $this, $key );
                return $file->getSize();
        }

        /**
         * Return the upload error or 0
         *
         * @param $key String:
         * @return integer
         */
        public function getUploadError( $key ) {
                $file = new WebRequestUpload( $this, $key );
                return $file->getError();
        }

        /**
         * Return the original filename of the uploaded file, as reported by
         * the submitting user agent. HTML-style character entities are
         * interpreted and normalized to Unicode normalization form C, in part
         * to deal with weird input from Safari with non-ASCII filenames.
         *
         * Other than this the name is not verified for being a safe filename.
         *
         * @param $key String:
         * @return string or NULL if no such file.
         */
        public function getFileName( $key ) {
                $file = new WebRequestUpload( $this, $key );
                return $file->getName();
        }

        /**
         * Return a WebRequestUpload object corresponding to the key
         *
         * @param @key string
         * @return WebRequestUpload
         */
        public function getUpload( $key ) {
                return new WebRequestUpload( $this, $key );
        }

        /**
         * Return a handle to WebResponse style object, for setting cookies,
         * headers and other stuff, for Request being worked on.
         *
         * @return WebResponse
         */
        public function response() {
                /* Lazy initialization of response object for this request */
                if ( !is_object( $this->response ) ) {
                        $class = ( $this instanceof FauxRequest ) ? 'FauxResponse' : 'WebResponse';
                        $this->response = new $class();
                }
                return $this->response;
        }

        /**
         * Get a request header, or false if it isn't set
         * @param $name String: case-insensitive header name
         */
        public function getHeader( $name ) {
                $name = strtoupper( $name );
                if ( function_exists( 'apache_request_headers' ) ) {
                        if ( !$this->headers ) {
                                foreach ( apache_request_headers() as $tempName => $tempValue ) {
                                        $this->headers[ strtoupper( $tempName ) ] = $tempValue;
                                }
                        }
                        if ( isset( $this->headers[$name] ) ) {
                                return $this->headers[$name];
                        } else {
                                return false;
                        }
                } else {
                        $name = 'HTTP_' . str_replace( '-', '_', $name );
                        if ( $name === 'HTTP_CONTENT_LENGTH' && !isset( $_SERVER[$name] ) ) {
                                $name = 'CONTENT_LENGTH';
                        }
                        if ( isset( $_SERVER[$name] ) ) {
                                return $_SERVER[$name];
                        } else {
                                return false;
                        }
                }
        }

        /**
         * Get data from $_SESSION
         *
         * @param $key String: name of key in $_SESSION
         * @return Mixed
         */
        public function getSessionData( $key ) {
                if( !isset( $_SESSION[$key] ) ) {
                        return null;
                }
                return $_SESSION[$key];
        }

        /**
         * Set session data
         *
         * @param $key String: name of key in $_SESSION
         * @param $data Mixed
         */
        public function setSessionData( $key, $data ) {
                $_SESSION[$key] = $data;
        }

        /**
         * Returns true if the PATH_INFO ends with an extension other than a script
         * extension. This could confuse IE for scripts that send arbitrary data which
         * is not HTML but may be detected as such.
         *
         * Various past attempts to use the URL to make this check have generally
         * run up against the fact that CGI does not provide a standard method to
         * determine the URL. PATH_INFO may be mangled (e.g. if cgi.fix_pathinfo=0),
         * but only by prefixing it with the script name and maybe some other stuff,
         * the extension is not mangled. So this should be a reasonably portable
         * way to perform this security check.
         */
        public function isPathInfoBad() {
                global $wgScriptExtension;

                if ( !isset( $_SERVER['PATH_INFO'] ) ) {
                        return false;
                }
                $pi = $_SERVER['PATH_INFO'];
                $dotPos = strrpos( $pi, '.' );
                if ( $dotPos === false ) {
                        return false;
                }
                $ext = substr( $pi, $dotPos );
                return !in_array( $ext, array( $wgScriptExtension, '.php', '.php5' ) );
        }

        /**
         * Parse the Accept-Language header sent by the client into an array
         * @return array( languageCode => q-value ) sorted by q-value in descending order
         * May contain the "language" '*', which applies to languages other than those explicitly listed.
         * This is aligned with rfc2616 section 14.4
         */
        public function getAcceptLang() {
                // Modified version of code found at http://www.thefutureoftheweb.com/blog/use-accept-language-header
                $acceptLang = $this->getHeader( 'Accept-Language' );
                if ( !$acceptLang ) {
                        return array();
                }

                // Return the language codes in lower case
                $acceptLang = strtolower( $acceptLang );

                // Break up string into pieces (languages and q factors)
                $lang_parse = null;
                preg_match_all( '/([a-z]{1,8}(-[a-z]{1,8})?|\*)\s*(;\s*q\s*=\s*(1|0(\.[0-9]+)?)?)?/',
                        $acceptLang, $lang_parse );

                if ( !count( $lang_parse[1] ) ) {
                        return array();
                }

                // Create a list like "en" => 0.8
                $langs = array_combine( $lang_parse[1], $lang_parse[4] );
                // Set default q factor to 1
                foreach ( $langs as $lang => $val ) {
                        if ( $val === '' ) {
                                $langs[$lang] = 1;
                        } else if ( $val == 0 ) {
                                unset($langs[$lang]);
                        }
                }

                // Sort list
                arsort( $langs, SORT_NUMERIC );
                return $langs;
        }
}

/**
 * Object to access the $_FILES array
 */
class WebRequestUpload {
        protected $request;
        protected $doesExist;
        protected $fileInfo;

        /**
         * Constructor. Should only be called by WebRequest
         *
         * @param $request WebRequest The associated request
         * @param $key string Key in $_FILES array (name of form field)
         */
        public function __construct( $request, $key ) {
                $this->request = $request;
                $this->doesExist = isset( $_FILES[$key] );
                if ( $this->doesExist ) {
                        $this->fileInfo = $_FILES[$key];
                }
        }

        /**
         * Return whether a file with this name was uploaded.
         *
         * @return bool
         */
        public function exists() {
                return $this->doesExist;
        }

        /**
         * Return the original filename of the uploaded file
         *
         * @return mixed Filename or null if non-existent
         */
        public function getName() {
                if ( !$this->exists() ) {
                        return null;
                }

                global $wgContLang;
                $name = $this->fileInfo['name'];

                # Safari sends filenames in HTML-encoded Unicode form D...
                # Horrid and evil! Let's try to make some kind of sense of it.
                $name = Sanitizer::decodeCharReferences( $name );
                $name = $wgContLang->normalize( $name );
                wfDebug( __METHOD__ . ": {$this->fileInfo['name']} normalized to '$name'\n" );
                return $name;
        }

        /**
         * Return the file size of the uploaded file
         *
         * @return int File size or zero if non-existent
         */
        public function getSize() {
                if ( !$this->exists() ) {
                        return 0;
                }

                return $this->fileInfo['size'];
        }

        /**
         * Return the path to the temporary file
         *
         * @return mixed Path or null if non-existent
         */
        public function getTempName() {
                if ( !$this->exists() ) {
                        return null;
                }

                return $this->fileInfo['tmp_name'];
        }

        /**
         * Return the upload error. See link for explanation
         * http://www.php.net/manual/en/features.file-upload.errors.php
         *
         * @return int One of the UPLOAD_ constants, 0 if non-existent
         */
        public function getError() {
                if ( !$this->exists() ) {
                        return 0; # UPLOAD_ERR_OK
                }

                return $this->fileInfo['error'];
        }

        /**
         * Returns whether this upload failed because of overflow of a maximum set
         * in php.ini
         *
         * @return bool
         */
        public function isIniSizeOverflow() {
                if ( $this->getError() == UPLOAD_ERR_INI_SIZE ) {
                        # PHP indicated that upload_max_filesize is exceeded
                        return true;
                }

                $contentLength = $this->request->getHeader( 'CONTENT_LENGTH' );
                if ( $contentLength > wfShorthandToInteger( ini_get( 'post_max_size' ) ) ) {
                        # post_max_size is exceeded
                        return true;
                }

                return false;
        }
}

/**
 * WebRequest clone which takes values from a provided array.
 *
 * @ingroup HTTP
 */
class FauxRequest extends WebRequest {
        private $wasPosted = false;
        private $session = array();

        /**
         * @param $data Array of *non*-urlencoded key => value pairs, the
         *   fake GET/POST values
         * @param $wasPosted Bool: whether to treat the data as POST
         * @param $session Mixed: session array or null
         */
        public function __construct( $data, $wasPosted = false, $session = null ) {
                if( is_array( $data ) ) {
                        $this->data = $data;
                } else {
                        throw new MWException( "FauxRequest() got bogus data" );
                }
                $this->wasPosted = $wasPosted;
                if( $session )
                        $this->session = $session;
        }

        private function notImplemented( $method ) {
                throw new MWException( "{$method}() not implemented" );
        }

        public function getText( $name, $default = '' ) {
                # Override; don't recode since we're using internal data
                return (string)$this->getVal( $name, $default );
        }

        public function getValues() {
                return $this->data;
        }

        public function wasPosted() {
                return $this->wasPosted;
        }

        public function checkSessionCookie() {
                return false;
        }

        public function getRequestURL() {
                $this->notImplemented( __METHOD__ );
        }

        public function appendQuery( $query ) {
                global $wgTitle;
                $basequery = '';
                foreach( $this->data as $var => $val ) {
                        if ( $var == 'title' ) {
                                continue;
                        }
                        if ( is_array( $val ) ) {
                                /* This will happen given a request like
                                 * http://en.wikipedia.org/w/index.php?title[]=Special:Userlogin&returnto[]=Main_Page
                                 */
                                continue;
                        }
                        $basequery .= '&' . urlencode( $var ) . '=' . urlencode( $val );
                }
                $basequery .= '&' . $query;

                # Trim the extra &
                $basequery = substr( $basequery, 1 );
                return $wgTitle->getLocalURL( $basequery );
        }

        public function getHeader( $name ) {
                return isset( $this->headers[$name] ) ? $this->headers[$name] : false;
        }

        public function setHeader( $name, $val ) {
                $this->headers[$name] = $val;
        }

        public function getSessionData( $key ) {
                if( isset( $this->session[$key] ) )
                        return $this->session[$key];
        }

        public function setSessionData( $key, $data ) {
                $this->session[$key] = $data;
        }

        public function isPathInfoBad() {
                return false;
        }
}