View file File name : Output.php Content :<?php /** * CodeIgniter * * An open source application development framework for PHP * * This content is released under the MIT License (MIT) * * Copyright (c) 2014 - 2019, British Columbia Institute of Technology * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * @package CodeIgniter * @author EllisLab Dev Team * @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/) * @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/) * @license https://opensource.org/licenses/MIT MIT License * @link https://codeigniter.com * @since Version 1.0.0 * @filesource */ defined('BASEPATH') OR exit('No direct script access allowed'); /** * Output Class * * Responsible for sending final output to the browser. * * @package CodeIgniter * @subpackage Libraries * @category Output * @author EllisLab Dev Team * @link https://codeigniter.com/user_guide/libraries/output.html */ class CI_Output { /** * Final output string * * @var string */ public $final_output; /** * Cache expiration time * * @var int */ public $cache_expiration = 0; /** * List of server headers * * @var array */ public $headers = array(); /** * List of mime types * * @var array */ public $mimes = array(); /** * Mime-type for the current page * * @var string */ protected $mime_type = 'text/html'; /** * Enable Profiler flag * * @var bool */ public $enable_profiler = FALSE; /** * php.ini zlib.output_compression flag * * @var bool */ protected $_zlib_oc = FALSE; /** * CI output compression flag * * @var bool */ protected $_compress_output = FALSE; /** * List of profiler sections * * @var array */ protected $_profiler_sections = array(); /** * Parse markers flag * * Whether or not to parse variables like {elapsed_time} and {memory_usage}. * * @var bool */ public $parse_exec_vars = TRUE; /** * mbstring.func_overload flag * * @var bool */ protected static $func_overload; /** * Class constructor * * Determines whether zLib output compression will be used. * * @return void */ public function __construct() { $this->_zlib_oc = (bool) ini_get('zlib.output_compression'); $this->_compress_output = ( $this->_zlib_oc === FALSE && config_item('compress_output') === TRUE && extension_loaded('zlib') ); isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload')); // Get mime types for later $this->mimes =& get_mimes(); log_message('info', 'Output Class Initialized'); } // -------------------------------------------------------------------- /** * Get Output * * Returns the current output string. * * @return string */ public function get_output() { return $this->final_output; } // -------------------------------------------------------------------- /** * Set Output * * Sets the output string. * * @param string $output Output data * @return CI_Output */ public function set_output($output) { $this->final_output = $output; return $this; } // -------------------------------------------------------------------- /** * Append Output * * Appends data onto the output string. * * @param string $output Data to append * @return CI_Output */ public function append_output($output) { $this->final_output .= $output; return $this; } // -------------------------------------------------------------------- /** * Set Header * * Lets you set a server header which will be sent with the final output. * * Note: If a file is cached, headers will not be sent. * @todo We need to figure out how to permit headers to be cached. * * @param string $header Header * @param bool $replace Whether to replace the old header value, if already set * @return CI_Output */ public function set_header($header, $replace = TRUE) { // If zlib.output_compression is enabled it will compress the output, // but it will not modify the content-length header to compensate for // the reduction, causing the browser to hang waiting for more data. // We'll just skip content-length in those cases. if ($this->_zlib_oc && strncasecmp($header, 'content-length', 14) === 0) { return $this; } $this->headers[] = array($header, $replace); return $this; } // -------------------------------------------------------------------- /** * Set Content-Type Header * * @param string $mime_type Extension of the file we're outputting * @param string $charset Character set (default: NULL) * @return CI_Output */ public function set_content_type($mime_type, $charset = NULL) { if (strpos($mime_type, '/') === FALSE) { $extension = ltrim($mime_type, '.'); // Is this extension supported? if (isset($this->mimes[$extension])) { $mime_type =& $this->mimes[$extension]; if (is_array($mime_type)) { $mime_type = current($mime_type); } } } $this->mime_type = $mime_type; if (empty($charset)) { $charset = config_item('charset'); } $header = 'Content-Type: '.$mime_type .(empty($charset) ? '' : '; charset='.$charset); $this->headers[] = array($header, TRUE); return $this; } // -------------------------------------------------------------------- /** * Get Current Content-Type Header * * @return string 'text/html', if not already set */ public function get_content_type() { for ($i = 0, $c = count($this->headers); $i < $c; $i++) { if (sscanf($this->headers[$i][0], 'Content-Type: %[^;]', $content_type) === 1) { return $content_type; } } return 'text/html'; } // -------------------------------------------------------------------- /** * Get Header * * @param string $header * @return string */ public function get_header($header) { // Combine headers already sent with our batched headers $headers = array_merge( // We only need [x][0] from our multi-dimensional array array_map('array_shift', $this->headers), headers_list() ); if (empty($headers) OR empty($header)) { return NULL; } // Count backwards, in order to get the last matching header for ($c = count($headers) - 1; $c > -1; $c--) { if (strncasecmp($header, $headers[$c], $l = self::strlen($header)) === 0) { return trim(self::substr($headers[$c], $l+1)); } } return NULL; } // -------------------------------------------------------------------- /** * Set HTTP Status Header * * As of version 1.7.2, this is an alias for common function * set_status_header(). * * @param int $code Status code (default: 200) * @param string $text Optional message * @return CI_Output */ public function set_status_header($code = 200, $text = '') { set_status_header($code, $text); return $this; } // -------------------------------------------------------------------- /** * Enable/disable Profiler * * @param bool $val TRUE to enable or FALSE to disable * @return CI_Output */ public function enable_profiler($val = TRUE) { $this->enable_profiler = is_bool($val) ? $val : TRUE; return $this; } // -------------------------------------------------------------------- /** * Set Profiler Sections * * Allows override of default/config settings for * Profiler section display. * * @param array $sections Profiler sections * @return CI_Output */ public function set_profiler_sections($sections) { if (isset($sections['query_toggle_count'])) { $this->_profiler_sections['query_toggle_count'] = (int) $sections['query_toggle_count']; unset($sections['query_toggle_count']); } foreach ($sections as $section => $enable) { $this->_profiler_sections[$section] = ($enable !== FALSE); } return $this; } // -------------------------------------------------------------------- /** * Set Cache * * @param int $time Cache expiration time in minutes * @return CI_Output */ public function cache($time) { $this->cache_expiration = is_numeric($time) ? $time : 0; return $this; } // -------------------------------------------------------------------- /** * Display Output * * Processes and sends finalized output data to the browser along * with any server headers and profile data. It also stops benchmark * timers so the page rendering speed and memory usage can be shown. * * Note: All "view" data is automatically put into $this->final_output * by controller class. * * @uses CI_Output::$final_output * @param string $output Output data override * @return void */ public function _display($output = '') { // Note: We use load_class() because we can't use $CI =& get_instance() // since this function is sometimes called by the caching mechanism, // which happens before the CI super object is available. $BM =& load_class('Benchmark', 'core'); $CFG =& load_class('Config', 'core'); // Grab the super object if we can. if (class_exists('CI_Controller', FALSE)) { $CI =& get_instance(); } // -------------------------------------------------------------------- // Set the output data if ($output === '') { $output =& $this->final_output; } // -------------------------------------------------------------------- // Do we need to write a cache file? Only if the controller does not have its // own _output() method and we are not dealing with a cache file, which we // can determine by the existence of the $CI object above if ($this->cache_expiration > 0 && isset($CI) && ! method_exists($CI, '_output')) { $this->_write_cache($output); } // -------------------------------------------------------------------- // Parse out the elapsed time and memory usage, // then swap the pseudo-variables with the data $elapsed = $BM->elapsed_time('total_execution_time_start', 'total_execution_time_end'); if ($this->parse_exec_vars === TRUE) { $memory = round(memory_get_usage() / 1024 / 1024, 2).'MB'; $output = str_replace(array('{elapsed_time}', '{memory_usage}'), array($elapsed, $memory), $output); } // -------------------------------------------------------------------- // Is compression requested? if (isset($CI) // This means that we're not serving a cache file, if we were, it would already be compressed && $this->_compress_output === TRUE && isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE) { ob_start('ob_gzhandler'); } // -------------------------------------------------------------------- // Are there any server headers to send? if (count($this->headers) > 0) { foreach ($this->headers as $header) { @header($header[0], $header[1]); } } // -------------------------------------------------------------------- // Does the $CI object exist? // If not we know we are dealing with a cache file so we'll // simply echo out the data and exit. if ( ! isset($CI)) { if ($this->_compress_output === TRUE) { if (isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE) { header('Content-Encoding: gzip'); header('Content-Length: '.self::strlen($output)); } else { // User agent doesn't support gzip compression, // so we'll have to decompress our cache $output = gzinflate(self::substr($output, 10, -8)); } } echo $output; log_message('info', 'Final output sent to browser'); log_message('debug', 'Total execution time: '.$elapsed); return; } // -------------------------------------------------------------------- // Do we need to generate profile data? // If so, load the Profile class and run it. if ($this->enable_profiler === TRUE) { $CI->load->library('profiler'); if ( ! empty($this->_profiler_sections)) { $CI->profiler->set_sections($this->_profiler_sections); } // If the output data contains closing </body> and </html> tags // we will remove them and add them back after we insert the profile data $output = preg_replace('|</body>.*?</html>|is', '', $output, -1, $count).$CI->profiler->run(); if ($count > 0) { $output .= '</body></html>'; } } // Does the controller contain a function named _output()? // If so send the output there. Otherwise, echo it. if (method_exists($CI, '_output')) { $CI->_output($output); } else { echo $output; // Send it to the browser! } log_message('info', 'Final output sent to browser'); log_message('debug', 'Total execution time: '.$elapsed); } // -------------------------------------------------------------------- /** * Write Cache * * @param string $output Output data to cache * @return void */ public function _write_cache($output) { $CI =& get_instance(); $path = $CI->config->item('cache_path'); $cache_path = ($path === '') ? APPPATH.'cache/' : $path; if ( ! is_dir($cache_path) OR ! is_really_writable($cache_path)) { log_message('error', 'Unable to write cache file: '.$cache_path); return; } $uri = $CI->config->item('base_url') .$CI->config->item('index_page') .$CI->uri->uri_string(); if (($cache_query_string = $CI->config->item('cache_query_string')) && ! empty($_SERVER['QUERY_STRING'])) { if (is_array($cache_query_string)) { $uri .= '?'.http_build_query(array_intersect_key($_GET, array_flip($cache_query_string))); } else { $uri .= '?'.$_SERVER['QUERY_STRING']; } } $cache_path .= md5($uri); if ( ! $fp = @fopen($cache_path, 'w+b')) { log_message('error', 'Unable to write cache file: '.$cache_path); return; } if ( ! flock($fp, LOCK_EX)) { log_message('error', 'Unable to secure a file lock for file at: '.$cache_path); fclose($fp); return; } // If output compression is enabled, compress the cache // itself, so that we don't have to do that each time // we're serving it if ($this->_compress_output === TRUE) { $output = gzencode($output); if ($this->get_header('content-type') === NULL) { $this->set_content_type($this->mime_type); } } $expire = time() + ($this->cache_expiration * 60); // Put together our serialized info. $cache_info = serialize(array( 'expire' => $expire, 'headers' => $this->headers )); $output = $cache_info.'ENDCI--->'.$output; for ($written = 0, $length = self::strlen($output); $written < $length; $written += $result) { if (($result = fwrite($fp, self::substr($output, $written))) === FALSE) { break; } } flock($fp, LOCK_UN); fclose($fp); if ( ! is_int($result)) { @unlink($cache_path); log_message('error', 'Unable to write the complete cache content at: '.$cache_path); return; } chmod($cache_path, 0640); log_message('debug', 'Cache file written: '.$cache_path); // Send HTTP cache-control headers to browser to match file cache settings. $this->set_cache_header($_SERVER['REQUEST_TIME'], $expire); } // -------------------------------------------------------------------- /** * Update/serve cached output * * @uses CI_Config * @uses CI_URI * * @param object &$CFG CI_Config class instance * @param object &$URI CI_URI class instance * @return bool TRUE on success or FALSE on failure */ public function _display_cache(&$CFG, &$URI) { $cache_path = ($CFG->item('cache_path') === '') ? APPPATH.'cache/' : $CFG->item('cache_path'); // Build the file path. The file name is an MD5 hash of the full URI $uri = $CFG->item('base_url').$CFG->item('index_page').$URI->uri_string; if (($cache_query_string = $CFG->item('cache_query_string')) && ! empty($_SERVER['QUERY_STRING'])) { if (is_array($cache_query_string)) { $uri .= '?'.http_build_query(array_intersect_key($_GET, array_flip($cache_query_string))); } else { $uri .= '?'.$_SERVER['QUERY_STRING']; } } $filepath = $cache_path.md5($uri); if ( ! file_exists($filepath) OR ! $fp = @fopen($filepath, 'rb')) { return FALSE; } flock($fp, LOCK_SH); $cache = (filesize($filepath) > 0) ? fread($fp, filesize($filepath)) : ''; flock($fp, LOCK_UN); fclose($fp); // Look for embedded serialized file info. if ( ! preg_match('/^(.*)ENDCI--->/', $cache, $match)) { return FALSE; } $cache_info = unserialize($match[1]); $expire = $cache_info['expire']; $last_modified = filemtime($filepath); // Has the file expired? if ($_SERVER['REQUEST_TIME'] >= $expire && is_really_writable($cache_path)) { // If so we'll delete it. @unlink($filepath); log_message('debug', 'Cache file has expired. File deleted.'); return FALSE; } // Send the HTTP cache control headers $this->set_cache_header($last_modified, $expire); // Add headers from cache file. foreach ($cache_info['headers'] as $header) { $this->set_header($header[0], $header[1]); } // Display the cache $this->_display(self::substr($cache, self::strlen($match[0]))); log_message('debug', 'Cache file is current. Sending it to browser.'); return TRUE; } // -------------------------------------------------------------------- /** * Delete cache * * @param string $uri URI string * @return bool */ public function delete_cache($uri = '') { $CI =& get_instance(); $cache_path = $CI->config->item('cache_path'); if ($cache_path === '') { $cache_path = APPPATH.'cache/'; } if ( ! is_dir($cache_path)) { log_message('error', 'Unable to find cache path: '.$cache_path); return FALSE; } if (empty($uri)) { $uri = $CI->uri->uri_string(); if (($cache_query_string = $CI->config->item('cache_query_string')) && ! empty($_SERVER['QUERY_STRING'])) { if (is_array($cache_query_string)) { $uri .= '?'.http_build_query(array_intersect_key($_GET, array_flip($cache_query_string))); } else { $uri .= '?'.$_SERVER['QUERY_STRING']; } } } $cache_path .= md5($CI->config->item('base_url').$CI->config->item('index_page').ltrim($uri, '/')); if ( ! @unlink($cache_path)) { log_message('error', 'Unable to delete cache file for '.$uri); return FALSE; } return TRUE; } // -------------------------------------------------------------------- /** * Set Cache Header * * Set the HTTP headers to match the server-side file cache settings * in order to reduce bandwidth. * * @param int $last_modified Timestamp of when the page was last modified * @param int $expiration Timestamp of when should the requested page expire from cache * @return void */ public function set_cache_header($last_modified, $expiration) { $max_age = $expiration - $_SERVER['REQUEST_TIME']; if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && $last_modified <= strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE'])) { $this->set_status_header(304); exit; } header('Pragma: public'); header('Cache-Control: max-age='.$max_age.', public'); header('Expires: '.gmdate('D, d M Y H:i:s', $expiration).' GMT'); header('Last-modified: '.gmdate('D, d M Y H:i:s', $last_modified).' GMT'); } // -------------------------------------------------------------------- /** * Byte-safe strlen() * * @param string $str * @return int */ protected static function strlen($str) { return (self::$func_overload) ? mb_strlen($str, '8bit') : strlen($str); } // -------------------------------------------------------------------- /** * Byte-safe substr() * * @param string $str * @param int $start * @param int $length * @return string */ protected static function substr($str, $start, $length = NULL) { if (self::$func_overload) { // mb_substr($str, $start, null, '8bit') returns an empty // string on PHP 5.3 isset($length) OR $length = ($start >= 0 ? self::strlen($str) - $start : -$start); return mb_substr($str, $start, $length, '8bit'); } return isset($length) ? substr($str, $start, $length) : substr($str, $start); } }