Ticket #4779: http.10.4.php

<?php
/**
 * Simple HTTP request fallback system
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 * @author Jacob Santos <wordpress@santosj.name>
 */

/**
 * Abstract class for all of the fallback implementation
 * classes. The implementation classes will extend this class
 * to keep common API methods universal between different
 * functionality.
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 */
class WP_Http
{

        /**
         * PHP4 style Constructor - Calls PHP5 Style Constructor
         *
         * @since {@internal Version Unknown}}
         * @return WP_Http
         */
        function WP_Http()
        {
                $this->__construct();
        }

        /**
         * PHP5 style Constructor - Setup available transport if not available.
         *
         * @since {@internal Version Unknown}}
         * @return WP_Http
         */
        function __construct()
        {
                WP_Http::_getTransport();
        }

        /**
         * Tests the WordPress HTTP objects for an object to use and returns it.
         *
         * Tests all of the objects and returns the object that passes. Also caches
         * that object to be used later.
         *
         * @since {@internal Version Unknown}}
         * @access private
         *
         * @return object|null Null if no transports are available, HTTP transport object.
         */
        function &_getTransport()
        {
                static $working_transport;

                if( is_null($working_transport) ) {
                        if( true === WP_Http_Streams::test() )
                                $working_transport = new WP_Http_Streams();
                        else if( true ===  WP_Http_ExtHttp::test() )
                                $working_transport = new WP_Http_ExtHttp();
                        else if( true === WP_Http_Fopen::test() )
                                $working_transport = new WP_Http_Fopen();
                        else if( true === WP_Http_Fsockopen::test() )
                                $working_transport = new WP_Http_Fsockopen();
                }

                return $working_transport;
        }

        /**
         * Tests the WordPress HTTP objects for an object to use and returns it.
         *
         * Tests all of the objects and returns the object that passes. Also caches
         * that object to be used later. This is for posting content to a URL and
         * is used when there is a body. The plain Fopen Transport can not be used
         * to send content, but the streams transport can. This is a limitation that
         * is addressed here.
         *
         * @since {@internal Version Unknown}}
         * @access private
         *
         * @return object|null Null if no transports are available, HTTP transport object.
         */
        function &_postTransport()
        {
                static $working_transport;

                if( is_null($working_transport) ) {
                        if( true === WP_Http_Streams::test() )
                                $working_transport = new WP_Http_Streams();
                        else if( true ===  WP_Http_ExtHttp::test() )
                                $working_transport = new WP_Http_ExtHttp();
                        else if( true === WP_Http_Fsockopen::test() )
                                $working_transport = new WP_Http_Fsockopen();
                }

                return $working_transport;
        }

        /**
         * Retrieve the location and set the class properties after the site has been retrieved.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string $url
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs. Expects sanitized.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @param str|array $type Optional. Should be an already processed array with HTTP arguments.
         * @return boolean
         */
        function request($url, $args=array(), $headers=null, $body=null)
        {
                global $wp_version;

                $defaults = array(
                        'method' => 'GET', 'timeout' => 3,
                        'redirection' => 5, 'redirected' => false,
                        'httpversion' => '1.0'
                );

                $r = wp_parse_args( $args, $defaults );

                if( !is_null($headers) && !is_array($headers) ) {
                        $processedHeaders = WP_Http::processHeaders($headers);
                        $headers = $processedHeaders['headers'];
                } else {
                        $headers = array();
                }

                if( !isset($headers['user-agent']) || !isset($headers['User-Agent']) )
                        $headers['user-agent'] = apply_filters('http_headers_useragent', 'WordPress/'.$wp_version );

                if( is_null($body) )
                        $transport = WP_Http::_getTransport();
                else
                        $transport = WP_Http::_postTransport();

                return $transport->request($url, $headers, $body, $r);
        }

        /**
         * Uses the POST HTTP method.
         * 
         * Used for sending data that is expected to be in the body.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string $url The location of the site and page to retrieve.
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @return boolean
         */
        function post($url, $args=array(), $headers=null, $body=null)
        {
                $defaults = array('method' => 'POST');
                $r = wp_parse_args( $args, $defaults );
                return $this->request($url, $headers, $body, $r);
        }

        /**
         * Uses the GET HTTP method. 
         *
         * Used for sending data that is expected to be in the body.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @return boolean
         */
        function get($url, $args=array(), $headers=null, $body=null)
        {
                $defaults = array('method' => 'GET');
                $r = wp_parse_args( $args, $defaults );
                return $this->request($url, $headers, $body, $r);
        }

        /**
         * Uses the HEAD HTTP method. 
         *
         * Used for sending data that is expected to be in the body.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @return boolean
         */
        function head($url, $args=array(), $headers=null, $body=null)
        {
                $defaults = array('method' => 'HEAD');
                $r = wp_parse_args( $args, $defaults );
                return $this->request($url, $r, $headers, $body);
        }

        /**
         * Parses the responses and splits the parts into headers and body.
         *
         * @access public
         * @static
         * @since {@internal Version Unknown}}
         *
         * @param string $strResponse The full response string
         * @return array Array with 'headers' and 'body' keys.
         */
        function processResponse($strResponse)
        {
                list($theHeaders, $theBody) = explode("\r\n\r\n", $strResponse, 2);
                return array('headers' => $theHeaders, 'body' => $theBody);
        }

        /**
         * Whether response code is in the 400 range.
         *
         * @access public
         * @static
         * @since {@internal Version Unknown}}
         *
         * @param array $response Array with code and message keys
         * @return bool True if 40x Response, false if something else.
         */
        function is400Response($response)
        {
                if( (int) substr($response, 0, 1) == 4 )
                        return true;
                return false;
        }

        /**
         * Whether the headers returned a redirect location.
         *
         * @access public
         * @static
         * @since {@internal Version Unknown}}
         *
         * @param array $headers Array with headers
         * @return bool True if Location header is found.
         */
        function isRedirect($headers)
        {
                if( isset($headers['location']) )
                        return true;
                return false;
        }

        /**
         * Transform header string into an array.
         *
         * Will overwrite the last header value, if it is not empty.
         *
         * @access public
         * @static
         * @since {@internal Version Unknown}}
         *
         * @param string|array $headers
         * @return array
         */
        function processHeaders($headers)
        {
                if( is_array($headers) )
                        return $headers;

                $headers = explode("\n", str_replace(array("\r"), '', $headers) );

                $response = array('code' => 0, 'message' => '');

                $newheaders = array();
                foreach($headers as $tempheader) {
                        if( empty($tempheader) )
                                continue;

                        if( false === strpos($tempheader, ':') ) {
                                list( , $iResponseCode, $strResponseMsg) = explode(" ", $tempheader, 3);
                                $response['code'] = $iResponseCode;
                                $response['message'] = $strResponseMsg;
                                continue;
                        }

                        list($key, $value) = explode(":", $tempheader, 2);

                        if( !empty($value) )
                                $newheaders[strtolower($key)] = trim($value);
                }

                return array('response' => $response, 'headers' => $newheaders);
        }
}

/**
 * HTTP request method uses fsockopen function to retrieve the url.
 *
 * Preferred method since it works with all WordPress supported PHP versions.
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 */
class WP_Http_Fsockopen
{
        /**
         * Retrieve the location and set the class properties after the site has been retrieved.
         *
         * @since {@internal Version Unknown}}
         * @access public
         * @param string $url
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs. Expects sanitized.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @param str|array $type Optional. Should be an already processed array with HTTP arguments.
         * @return boolean
         */
        function request($url, $args=array(), $headers=null, $body=null)
        {
                $defaults = array(
                        'method' => 'GET', 'timeout' => 3,
                        'redirection' => 5, 'httpversion' => '1.0'
                );

                $r = wp_parse_args( $args, $defaults );

                $iError = null; // Store error number
                $strError = null; // Store error string

                $arrURL = parse_url($url);

                $secure_transport = false;

                if( !isset($arrURL['port']) ) {
                        if( (($arrURL['scheme'] == 'ssl' || $arrURL['scheme'] == 'https')) && extension_loaded('openssl') ) {
                                $arrURL['host'] = 'ssl://'.$arrURL['host'];
                                $arrURL['port'] = apply_filters('http_request_default_port', 443);
                                $secure_transport = true;
                        }
                        else
                                $arrURL['port'] = apply_filters('http_request_default_port', 80);
                }
                else
                        $arrURL['port'] = apply_filters('http_request_port', $arrURL['port']);

                if( true === $secure_transport )
                        $error_reporting = error_reporting(0);

                $handle = fsockopen($arrURL['host'], $arrURL['port'], $iError, $strError, apply_filters('http_request_timeout', absint($r['timeout']) ) );

                if( false === $handle ) {
                        return new WP_Error('http_request_failed', $iError.': '.$strError);
                }

                $requestPath = $arrURL['path'] . ( isset($arrURL['query']) ? '?' . $arrURL['query'] : '' );
                $requestPath = (empty($requestPath)) ? '/' : $requestPath;

                $strHeaders = '';
                $strHeaders .= strtoupper($r['method']).' '.$requestPath.' HTTP/'.$r['httpversion']."\r\n";
                $strHeaders .= 'Host: '.$arrURL['host']."\r\n";

                if( is_array($header) ) {
                        foreach( (array) $this->getHeaders() as $header => $headerValue)
                                $strHeaders .= $header.': '.$headerValue."\r\n";
                } else
                        $strHeaders .= $header;

                $strHeaders .= "\r\n";

                if( !is_null($body) )
                        $strHeaders .= $body;

                fwrite($handle, $strHeaders);

                $strResponse = '';
                while( !feof($handle) ) {
                        $strResponse .= fread($handle, 4096);
                }
                fclose($handle);

                if( true === $secure_transport )
                        error_reporting($error_reporting);

                $process = WP_Http::processResponse($strResponse);
                $arrHeaders = WP_Http::processHeaders($process['headers']);

                if( WP_Http::is400Response($arrHeaders['response']) )
                        return new WP_Error('http_request_failed', $arrHeaders['response']['code'] .': '. $arrHeaders['response']['message']);

                if( isset($arrHeaders['headers']['location']) ) {
                        if( $r['redirection']-- > 0 ) {
                                return $this->request($arrHeaders['headers']['location'], $r, $headers, $body);
                        } else
                                return new WP_Error('http_request_failed', __('Too many redirects.'));
                }

                return array('headers' => $arrHeaders['headers'], 'body' => $process['body'], 'response' => $arrHeaders['response']);
        }

        /**
         * Whether this class can be used for retrieving an URL.
         *
         * @since {@internal Version Unknown}}
         * @static
         * @return boolean False means this class can not be used, true means it can.
         */
        function test()
        {
                if( function_exists( 'fsockopen' ) )
                        return true;

                return false;
        }
}

/**
 * HTTP request method uses fopen function to retrieve the url.
 *
 * Requires PHP version greater than 4.3.0 for stream support. Does not allow
 * for $context support, but should still be okay, to write the headers, before
 * getting the response. Also requires that 'allow_url_fopen' to be enabled.
 *
 * Second preferred method for handling the retrieving the url for PHP 4.3+.
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 */
class WP_Http_Fopen
{
        /**
         * Retrieve the location and set the class properties after the site has been retrieved.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string $url
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs. Expects sanitized.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @param str|array $type Optional. Should be an already processed array with HTTP arguments.
         * @return boolean
         */
        function request($url, $args=array(), $headers=null, $body=null)
        {
                global $http_response_header;

                $defaults = array(
                        'method' => 'GET', 'timeout' => 3,
                        'redirection' => 5, 'httpversion' => '1.0'
                );

                $r = wp_parse_args( $args, $defaults );

                $arrURL = parse_url($url);

                if( 'http' != $arrURL['scheme'] || 'https' != $arrURL['scheme'] )
                        $url = str_replace($arrURL['scheme'], 'http', $url);

                $handle = fopen($url, 'rb');

                if(!$handle)
                        return new WP_Error('http_request_failed', sprintf(__("Could not open handle for fopen() to %s"), $url));

                if( function_exists('stream_set_timeout') )
                        stream_set_timeout($handle, apply_filters('http_request_timeout', $r['timeout']) );

                $strResponse = '';
                while(!feof($handle)) {
                        $strResponse .= fread($handle, 4096);
                }

                $theHeaders = '';
                if( function_exists('stream_get_meta_data') ) {
                        $meta = stream_get_meta_data($handle);
                        $theHeaders = $meta['wrapper_data'];
                } else {
                        $theHeaders = $http_response_header;
                }
                fclose($handle);

                $processedHeaders = WP_Http::processHeaders($theHeaders);
                return array('headers' => $processedHeaders['headers'], 'body' => $strResponse, 'response' => $processedHeaders['response']);
        }

        /**
         * Whether this class can be used for retrieving an URL.
         *
         * @static
         * @return boolean False means this class can not be used, true means it can.
         */
        function test()
        {
                if( !function_exists('fopen') || (function_exists('ini_get') && true != ini_get('allow_url_fopen')) )
                        return false;

                return true;
        }
}

/**
 * HTTP request method uses Streams to retrieve the url.
 *
 * Requires PHP 5.0+ and uses fopen with stream context. Requires that
 * 'allow_url_fopen' PHP setting to be enabled.
 *
 * Second preferred method for getting the URL, for PHP 5.
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 */
class WP_Http_Streams
{
        /**
         * Retrieve the location and set the class properties after the site has been retrieved.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string $url
         * @param str|array $args Optional. Override the defaults.
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs. Expects sanitized.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @return boolean
         */
        function request($url, $args=array(), $headers=null, $body=null)
        {
                $defaults = array(
                        'method' => 'GET', 'timeout' => 3,
                        'redirection' => 5, 'httpversion' => '1.0'
                );

                $r = wp_parse_args( $args, $defaults );

                $arrURL = parse_url($url);

                if( 'http' != $arrURL['scheme'] || 'https' != $arrURL['scheme'] )
                        $url = str_replace($arrURL['scheme'], 'http', $url);

                $arrContext = array('http' => 
                        array(
                                'method' => strtoupper($r['method']),
                                'user-agent' => $headers['User-Agent'],
                                'max_redirects' => $r['redirection'],
                                'protocol_version' => (float) $r['httpversion'],
                                'header' => $headers
                        )
                );

                if( !is_null($body) )
                        $arrContext['http']['content'] = $body;

                $context = stream_context_create($arrContext);

                $handle = fopen($url, 'rb', false, $context);

                stream_set_timeout($handle, apply_filters('http_request_stream_timeout', $this->timeout) );

                if(!$handle)
                        return new WP_Error('http_request_failed', sprintf(__("Could not open handle for fopen() to %s"), $url));

                $strResponse = stream_get_contents($handle);
                $meta = stream_get_meta_data($handle);

                fclose($handle);

                $processedHeaders = WP_Http::processHeaders($meta['wrapper_data']);
                return array('headers' => $processedHeaders['headers'], 'body' => $strResponse, 'response' => $processedHeaders['response']);
        }

        /**
         * Whether this class can be used for retrieving an URL.
         *
         * @static
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @return boolean False means this class can not be used, true means it can.
         */
        function test()
        {
                if( !function_exists('fopen') || (function_exists('ini_get') && true != ini_get('allow_url_fopen')) )
                        return false;

                if( version_compare(PHP_VERSION, '5.0', '<') )
                        return false;

                return true;
        }
}

/**
 * HTTP request method uses HTTP extension to retrieve the url.
 *
 * Requires the HTTP extension to be installed.
 *
 * Last ditch effort to retrieve the URL before complete failure.
 *
 * @package WordPress
 * @subpackage HTTP
 * @since {@internal Version Unknown}}
 */
class WP_Http_ExtHTTP
{
        /**
         * Retrieve the location and set the class properties after the site has been retrieved.
         *
         * @access public
         * @since {@internal Version Unknown}}
         *
         * @param string $url
         * @param str|array $args Optional. Override the defaults.
         * @param string|array $headers Optional. Either the header string or array of Header name and value pairs. Expects sanitized.
         * @param string $body Optional. The body that should be sent. Expected to be already processed.
         * @return boolean
         */
        function request($url, $args=array(), $headers=null, $body=null)
        {
                global $wp_version;

                $defaults = array(
                        'method' => 'GET', 'timeout' => 3,
                        'redirection' => 5, 'httpversion' => '1.0',
                        'user_agent' => apply_filters('http_headers_useragent', 'WordPress/'.$wp_version)
                );

                $r = wp_parse_args( $args, $defaults );

                if( isset($headers['User-Agent']) )
                        unset($headers['User-Agent']);

                switch($r['method'])
                {
                        case 'GET':
                                $r['method'] = HTTP_METH_GET;
                                break;
                        case 'POST':
                                $r['method'] = HTTP_METH_POST;
                                break;
                        case 'HEAD':
                                $r['method'] = HTTP_METH_HEAD;
                                break;
                        default:
                                $r['method'] = HTTP_METH_GET;
                }

                $arrURL = parse_url($url);

                if( 'http' != $arrURL['scheme'] || 'https' != $arrURL['scheme'] )
                        $url = str_replace($arrURL['scheme'], 'http', $url);

                $options = array(
                        'timeout' => $this->timeout,
                        'connecttimeout' => apply_filters('http_request_stream_timeout', $this->timeout),
                        'redirect' => apply_filters('http_request_redirect', 3),
                        'useragent' => $r['user_agent'],
                        'headers' => $headers,
                );

                $strResponse = http_request($r['method'], $url, $body, $options, $info);

                if( false === $strResponse )
                        return new WP_Error('http_request_failed', $info['response_code'] .': '. $info['error']);

                list($theHeaders, $theBody) = explode("\r\n\r\n", $strResponse, 2);
                $theHeaders = WP_Http::processHeaders($theHeaders);

                $theResponse = array();
                $theResponse['response']['code'] = $info['response_code'];
                $theResponse['response']['message'] = get_status_header_desc($info['response_code']);

                return array('headers' => $theHeaders['headers'], 'body' => $theBody, 'response' => $theResponse);
        }

        /**
         * Whether this class can be used for retrieving an URL.
         *
         * @static
         * @since {@internal Version Unknown}}
         *
         * @return boolean False means this class can not be used, true means it can.
         */
        function test()
        {
                if( function_exists('http_request') )
                        return true;

                return false;
        }
}

/**
 * Returns the initialized WP_Http Object
 *
 * @since {@internal Version Unknown}}
 * @access private
 *
 * @return WP_Http HTTP Transport object.
 */
function &_wp_http_get_object() {
        static $http;

        if( is_null($http) )
                $http = new WP_Http();

        return $http;
}

/**
 * Retrieve the raw response from the HTTP request.
 *
 * The array structure is a little complex.
 *
 * <code>
 * $res = array( 'headers' =>
 *              'response' => array('code', 'message'),
 *              'headers' => array()
 * );
 * </code>
 *
 * All of the headers in $res['headers']['headers'] are with the name as the key
 * and the value as the value. So to get the User-Agent, you would do the
 * following.
 *
 * <code>
 * $user_agent = $res['headers']['headers']['user-agent'];
 * </code>
 *
 * The body is the raw response content and can be retrieved from $res['body'].
 *
 * This function is called first to make the request and there are other API
 * functions to abstract out the above convoluted setup.
 *
 * @since {@internal Version Unknown}}
 *
 * @param string $url Site URL to retrieve.
 * @param array $args Optional. Override the defaults.
 * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
 * @param string $body Optional. The body that should be sent. Expected to be already processed.
 * @return string The body of the response
 */
function wp_remote_request($url, $args=array(), $headers=null, $body=null) {
        $objFetchSite = _wp_http_get_object();

        return $objFetchSite->request($url, $headers, $body, $args);
}

/**
 * Retrieve the raw response from the HTTP request using the GET method.
 *
 * @see wp_remote_request() For more information on the response array format.
 *
 * @since {@internal Version Unknown}}
 *
 * @param string $url Site URL to retrieve.
 * @param array $args Optional. Override the defaults.
 * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
 * @param string $body Optional. The body that should be sent. Expected to be already processed.
 * @return string The body of the response
 */
function wp_remote_get($url, $args=array(), $headers=null, $body=null) {
        $objFetchSite = _wp_http_get_object();

        return $objFetchSite->get($url, $headers, $body, $args);
}

/**
 * Retrieve the raw response from the HTTP request using the POST method.
 *
 * @see wp_remote_request() For more information on the response array format.
 *
 * @since {@internal Version Unknown}}
 *
 * @param string $url Site URL to retrieve.
 * @param array $args Optional. Override the defaults.
 * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
 * @param string $body Optional. The body that should be sent. Expected to be already processed.
 * @return string The body of the response
 */
function wp_remote_post($url, $args=array(), $headers=null, $body=null) {
        $objFetchSite = _wp_http_get_object();

        return $objFetchSite->post($url, $headers, $body, $args);
}

/**
 * Retrieve the raw response from the HTTP request using the HEAD method.
 *
 * @see wp_remote_request() For more information on the response array format.
 *
 * @since {@internal Version Unknown}}
 *
 * @param string $url Site URL to retrieve.
 * @param array $args Optional. Override the defaults.
 * @param string|array $headers Optional. Either the header string or array of Header name and value pairs.
 * @param string $body Optional. The body that should be sent. Expected to be already processed.
 * @return string The body of the response
 */
function wp_remote_head($url, $args=array(), $headers=null, $body=null) {
        $objFetchSite = _wp_http_get_object();

        return $objFetchSite->head($url, $headers, $body, $args);
}

/**
 * Retrieve only the headers from the raw response.
 *
 * @since {@internal Version Unknown}}
 *
 * @param array $response HTTP response.
 * @return array The headers of the response. Empty array if incorrect parameter given.
 */
function wp_remote_retrieve_headers(&$response) {
        if( !isset($response['headers']) || !is_array($response['headers']))
                return array();

        return $response['headers'];
}

/**
 * Retrieve a single header by name from the raw response.
 *
 * @since {@internal Version Unknown}}
 *
 * @param array $response
 * @param string $header Header name to retrieve value from.
 * @return array The header value. Empty string on if incorrect parameter given.
 */
function wp_remote_retrieve_header(&$response, $header) {
        if( !isset($response['headers']) || !is_array($response['headers']))
                return '';

        if( array_key_exists($header, $response['headers']) )
                return $response['headers'][$header];

        return '';
}

/**
 * Retrieve only the response code from the raw response.
 *
 * Will return an empty array if incorrect parameter value is given.
 *
 * @since {@internal Version Unknown}}
 *
 * @param array $response HTTP response.
 * @return array The keys 'code' and 'message' give information on the response.
 */
function wp_remote_retrieve_response_code(&$response) {
        if( !isset($response['response']) || !is_array($response['response']))
                return '';

        return $response['response']['code'];
}

/**
 * Retrieve only the response message from the raw response.
 *
 * Will return an empty array if incorrect parameter value is given.
 *
 * @since {@internal Version Unknown}}
 *
 * @param array $response HTTP response.
 * @return array The keys 'code' and 'message' give information on the response.
 */
function wp_remote_retrieve_response_message(&$response) {
        if( !isset($response['response']) || !is_array($response['response']))
                return '';

        return $response['response']['message'];
}

/**
 * Retrieve only the body from the raw response.
 *
 * @since {@internal Version Unknown}}
 *
 * @param array $response HTTP response.
 * @return string The body of the response. Empty string if no body or incorrect parameter given.
 */
function wp_remote_retrieve_body(&$response) {
        if( !isset($response['body']) )
                return '';

        return $response['body'];
}

?>