wordpress学习第六篇（wp-includes/load.php）

<?php/** * These functions are needed to load WordPress. * * @internal This file must be parsable by PHP4. * * @package WordPress *//** * Turn register globals off. * * @access private * @since 2.1.0 * @return null Will return null if register_globals PHP directive was disabled */function wp_unregister_GLOBALS() {if ( !ini_get( 'register_globals' ) )return;if ( isset( $_REQUEST['GLOBALS'] ) )die( /*WP_I18N_GLOBALS_OVERWRITE*/'GLOBALS overwrite attempt detected'/*/WP_I18N_GLOBALS_OVERWRITE*/ );// Variables that shouldn't be unset$no_unset = array( 'GLOBALS', '_GET', '_POST', '_COOKIE', '_REQUEST', '_SERVER', '_ENV', '_FILES', 'table_prefix' );$input = array_merge( $_GET, $_POST, $_COOKIE, $_SERVER, $_ENV, $_FILES, isset( $_SESSION ) && is_array( $_SESSION ) ? $_SESSION : array() );foreach ( $input as $k => $v )if ( !in_array( $k, $no_unset ) && isset( $GLOBALS[$k] ) ) {$GLOBALS[$k] = null;unset( $GLOBALS[$k] );}}/** * Fix $_SERVER variables for various setups. * * @access private * @since 3.0.0 */function wp_fix_server_vars() {global $PHP_SELF;$default_server_values = array('SERVER_SOFTWARE' => '','REQUEST_URI' => '',);$_SERVER = array_merge( $default_server_values, $_SERVER );// Fix for IIS when running with PHP ISAPIif ( empty( $_SERVER['REQUEST_URI'] ) || ( php_sapi_name() != 'cgi-fcgi' && preg_match( '/^Microsoft-IIS\//', $_SERVER['SERVER_SOFTWARE'] ) ) ) {// IIS Mod-Rewriteif ( isset( $_SERVER['HTTP_X_ORIGINAL_URL'] ) ) {$_SERVER['REQUEST_URI'] = $_SERVER['HTTP_X_ORIGINAL_URL'];}// IIS Isapi_Rewriteelse if ( isset( $_SERVER['HTTP_X_REWRITE_URL'] ) ) {$_SERVER['REQUEST_URI'] = $_SERVER['HTTP_X_REWRITE_URL'];} else {// Use ORIG_PATH_INFO if there is no PATH_INFOif ( !isset( $_SERVER['PATH_INFO'] ) && isset( $_SERVER['ORIG_PATH_INFO'] ) )$_SERVER['PATH_INFO'] = $_SERVER['ORIG_PATH_INFO'];// Some IIS + PHP configurations puts the script-name in the path-info (No need to append it twice)if ( isset( $_SERVER['PATH_INFO'] ) ) {if ( $_SERVER['PATH_INFO'] == $_SERVER['SCRIPT_NAME'] )$_SERVER['REQUEST_URI'] = $_SERVER['PATH_INFO'];else$_SERVER['REQUEST_URI'] = $_SERVER['SCRIPT_NAME'] . $_SERVER['PATH_INFO'];}// Append the query string if it exists and isn't nullif ( ! empty( $_SERVER['QUERY_STRING'] ) ) {$_SERVER['REQUEST_URI'] .= '?' . $_SERVER['QUERY_STRING'];}}}// Fix for PHP as CGI hosts that set SCRIPT_FILENAME to something ending in php.cgi for all requestsif ( isset( $_SERVER['SCRIPT_FILENAME'] ) && ( strpos( $_SERVER['SCRIPT_FILENAME'], 'php.cgi' ) == strlen( $_SERVER['SCRIPT_FILENAME'] ) - 7 ) )$_SERVER['SCRIPT_FILENAME'] = $_SERVER['PATH_TRANSLATED'];// Fix for Dreamhost and other PHP as CGI hostsif ( strpos( $_SERVER['SCRIPT_NAME'], 'php.cgi' ) !== false )unset( $_SERVER['PATH_INFO'] );// Fix empty PHP_SELF$PHP_SELF = $_SERVER['PHP_SELF'];if ( empty( $PHP_SELF ) )$_SERVER['PHP_SELF'] = $PHP_SELF = preg_replace( '/(\?.*)?$/', '', $_SERVER["REQUEST_URI"] );}/** * Check for the required PHP version, and the MySQL extension or a database drop-in. * * Dies if requirements are not met. * * This function must be able to work without a complete environment set up. In wp-load.php, for * example, WP_CONTENT_DIR is defined and version.php is included before this function is called. * * @access private * @since 3.0.0 */function wp_check_php_mysql_versions() {// we can probably extend this function to check if wp_die() exists then use translated strings, and then use it in install.php etc.global $required_php_version, $wp_version;$php_version = phpversion();if ( version_compare( $required_php_version, $php_version, '>' ) )die( sprintf( /*WP_I18N_OLD_PHP*/'Your server is running PHP version %1$s but WordPress %2$s requires at least %3$s.'/*/WP_I18N_OLD_PHP*/, $php_version, $wp_version, $required_php_version ) );if ( !extension_loaded( 'mysql' ) && !file_exists( WP_CONTENT_DIR . '/db.php' ) )die( /*WP_I18N_OLD_MYSQL*/'Your PHP installation appears to be missing the MySQL extension which is required by WordPress.'/*/WP_I18N_OLD_MYSQL*/ );}/** * Don't load all of WordPress when handling a favicon.ico request. * Instead, send the headers for a zero-length favicon and bail. * * @since 3.0.0 */function wp_favicon_request() {if ( '/favicon.ico' == $_SERVER['REQUEST_URI'] ) {header('Content-Type: image/vnd.microsoft.icon');header('Content-Length: 0');exit;}}/** * Dies with a maintenance message when conditions are met. * * Checks for a file in the WordPress root directory named ".maintenance". * This file will contain the variable $upgrading, set to the time the file * was created. If the file was created less than 10 minutes ago, WordPress * enters maintenance mode and displays a message. * * The default message can be replaced by using a drop-in (maintenance.php in * the wp-content directory). * * @access private * @since 3.0.0 */function wp_maintenance() {if ( !file_exists( ABSPATH . '.maintenance' ) || defined( 'WP_INSTALLING' ) )return;global $upgrading;include( ABSPATH . '.maintenance' );// If the $upgrading timestamp is older than 10 minutes, don't die.if ( ( time() - $upgrading ) >= 600 )return;if ( file_exists( WP_CONTENT_DIR . '/maintenance.php' ) ) {require_once( WP_CONTENT_DIR . '/maintenance.php' );die();}$protocol = $_SERVER["SERVER_PROTOCOL"];if ( 'HTTP/1.1' != $protocol && 'HTTP/1.0' != $protocol )$protocol = 'HTTP/1.0';header( "$protocol 503 Service Unavailable", true, 503 );header( 'Content-Type: text/html; charset=utf-8' );header( 'Retry-After: 600' );?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title><?php echo /*WP_I18N_MAINTENANCE*/'Maintenance'/*/WP_I18N_MAINTENANCE*/; ?></title></head><body><h1><?php echo /*WP_I18N_MAINT_MSG*/'Briefly unavailable for scheduled maintenance. Check back in a minute.'/*/WP_I18N_MAINT_MSG*/; ?></h1></body></html><?phpdie();}/** * PHP 4 standard microtime start capture. * * @access private * @since 0.71 * @global int $timestart Seconds and Microseconds added together from when function is called. * @return bool Always returns true. */function timer_start() {global $timestart;$mtime = explode( ' ', microtime() );$timestart = $mtime[1] + $mtime[0];return true;}/** * Return and/or display the time from the page start to when function is called. * * You can get the results and print them by doing: * <code> * $nTimePageTookToExecute = timer_stop(); * echo $nTimePageTookToExecute; * </code> * * Or instead, you can do: * <code> * timer_stop(1); * </code> * which will do what the above does. If you need the result, you can assign it to a variable, but * most cases, you only need to echo it. * * @since 0.71 * @global int $timestart Seconds and Microseconds added together from when timer_start() is called * @global int $timeend  Seconds and Microseconds added together from when function is called * * @param int $display Use '0' or null to not echo anything and 1 to echo the total time * @param int $precision The amount of digits from the right of the decimal to display. Default is 3. * @return float The "second.microsecond" finished time calculation */function timer_stop( $display = 0, $precision = 3 ) { // if called like timer_stop(1), will echo $timetotalglobal $timestart, $timeend;$mtime = microtime();$mtime = explode( ' ', $mtime );$timeend = $mtime[1] + $mtime[0];$timetotal = $timeend - $timestart;$r = ( function_exists( 'number_format_i18n' ) ) ? number_format_i18n( $timetotal, $precision ) : number_format( $timetotal, $precision );if ( $display )echo $r;return $r;}/** * Sets PHP error handling and handles WordPress debug mode. * * Uses three constants: WP_DEBUG, WP_DEBUG_DISPLAY, and WP_DEBUG_LOG. All three can be * defined in wp-config.php. Example: <code> define( 'WP_DEBUG', true ); </code> * * WP_DEBUG_DISPLAY and WP_DEBUG_LOG perform no function unless WP_DEBUG is true. * WP_DEBUG defaults to false. * * When WP_DEBUG is true, all PHP notices are reported. WordPress will also display * notices, including one when a deprecated WordPress function, function argument, * or file is used. Deprecated code may be removed from a later version. * * It is strongly recommended that plugin and theme developers use WP_DEBUG in their * development environments. * * When WP_DEBUG_DISPLAY is true, WordPress will force errors to be displayed. * WP_DEBUG_DISPLAY defaults to true. Defining it as false prevents WordPress from * changing the global configuration setting. (Defining WP_DEBUG_DISPLAY as false * will never force errors to be hidden.) * * When WP_DEBUG_LOG is true, errors will be logged to wp-content/debug.log. * WP_DEBUG_LOG defaults to false. * * @access private * @since 3.0.0 */function wp_debug_mode() {if ( WP_DEBUG ) {// E_DEPRECATED is a core PHP constant in PHP 5.3. Don't define this yourself.// The two statements are equivalent, just one is for 5.3+ and for less than 5.3.if ( defined( 'E_DEPRECATED' ) )error_reporting( E_ALL & ~E_DEPRECATED & ~E_STRICT );elseerror_reporting( E_ALL );if ( WP_DEBUG_DISPLAY )ini_set( 'display_errors', 1 );if ( WP_DEBUG_LOG ) {ini_set( 'log_errors', 1 );ini_set( 'error_log', WP_CONTENT_DIR . '/debug.log' );}} else {error_reporting( E_CORE_ERROR | E_CORE_WARNING | E_COMPILE_ERROR | E_ERROR | E_WARNING | E_PARSE | E_USER_ERROR | E_USER_WARNING | E_RECOVERABLE_ERROR );}}/** * Sets the location of the language directory. * * To set directory manually, define <code>WP_LANG_DIR</code> in wp-config.php. * * If the language directory exists within WP_CONTENT_DIR that is used * Otherwise if the language directory exists within WPINC, that's used * Finally, If neither of the preceeding directories is found, * WP_CONTENT_DIR/languages is used. * * The WP_LANG_DIR constant was introduced in 2.1.0. * * @access private * @since 3.0.0 */function wp_set_lang_dir() {if ( !defined( 'WP_LANG_DIR' ) ) {if ( file_exists( WP_CONTENT_DIR . '/languages' ) && @is_dir( WP_CONTENT_DIR . '/languages' ) || !@is_dir(ABSPATH . WPINC . '/languages') ) {define( 'WP_LANG_DIR', WP_CONTENT_DIR . '/languages' ); // no leading slash, no trailing slash, full path, not relative to ABSPATHif ( !defined( 'LANGDIR' ) ) {// Old static relative path maintained for limited backwards compatibility - won't work in some casesdefine( 'LANGDIR', 'wp-content/languages' );}} else {define( 'WP_LANG_DIR', ABSPATH . WPINC . '/languages' ); // no leading slash, no trailing slash, full path, not relative to ABSPATHif ( !defined( 'LANGDIR' ) ) {// Old relative path maintained for backwards compatibilitydefine( 'LANGDIR', WPINC . '/languages' );}}}}/** * Load the correct database class file. * * This function is used to load the database class file either at runtime or by * wp-admin/setup-config.php. We must globalize $wpdb to ensure that it is * defined globally by the inline code in wp-db.php. * * @since 2.5.0 * @global $wpdb WordPress Database Object */function require_wp_db() {global $wpdb;require_once( ABSPATH . WPINC . '/wp-db.php' );if ( file_exists( WP_CONTENT_DIR . '/db.php' ) )require_once( WP_CONTENT_DIR . '/db.php' );if ( isset( $wpdb ) )return;$wpdb = new wpdb( DB_USER, DB_PASSWORD, DB_NAME, DB_HOST );}/** * Sets the database table prefix and the format specifiers for database table columns. * * Columns not listed here default to %s. * * @see wpdb::$field_types Since 2.8.0 * @see wpdb::prepare() * @see wpdb::insert() * @see wpdb::update() * @see wpdb::set_prefix() * * @access private * @since 3.0.0 */function wp_set_wpdb_vars() {global $wpdb, $table_prefix;if ( !empty( $wpdb->error ) )dead_db();$wpdb->field_types = array( 'post_author' => '%d', 'post_parent' => '%d', 'menu_order' => '%d', 'term_id' => '%d', 'term_group' => '%d', 'term_taxonomy_id' => '%d','parent' => '%d', 'count' => '%d','object_id' => '%d', 'term_order' => '%d', 'ID' => '%d', 'commment_ID' => '%d', 'comment_post_ID' => '%d', 'comment_parent' => '%d','user_id' => '%d', 'link_id' => '%d', 'link_owner' => '%d', 'link_rating' => '%d', 'option_id' => '%d', 'blog_id' => '%d', 'meta_id' => '%d', 'post_id' => '%d','user_status' => '%d', 'umeta_id' => '%d', 'comment_karma' => '%d', 'comment_count' => '%d',// multisite:'active' => '%d', 'cat_id' => '%d', 'deleted' => '%d', 'lang_id' => '%d', 'mature' => '%d', 'public' => '%d', 'site_id' => '%d', 'spam' => '%d',);$prefix = $wpdb->set_prefix( $table_prefix );if ( is_wp_error( $prefix ) )wp_die( /*WP_I18N_BAD_PREFIX*/'<strong>ERROR</strong>: <code>$table_prefix</code> in <code>wp-config.php</code> can only contain numbers, letters, and underscores.'/*/WP_I18N_BAD_PREFIX*/ );}/** * Starts the WordPress object cache. * * If an object-cache.php file exists in the wp-content directory, * it uses that drop-in as an external object cache. * * @access private * @since 3.0.0 */function wp_start_object_cache() {global $_wp_using_ext_object_cache;$first_init = false; if ( ! function_exists( 'wp_cache_init' ) ) {if ( file_exists( WP_CONTENT_DIR . '/object-cache.php' ) ) {require_once ( WP_CONTENT_DIR . '/object-cache.php' );$_wp_using_ext_object_cache = true;} else {require_once ( ABSPATH . WPINC . '/cache.php' );$_wp_using_ext_object_cache = false;}$first_init = true;} else if ( !$_wp_using_ext_object_cache && file_exists( WP_CONTENT_DIR . '/object-cache.php' ) ) {// Sometimes advanced-cache.php can load object-cache.php before it is loaded here.// This breaks the function_exists check above and can result in $_wp_using_ext_object_cache// being set incorrectly.  Double check if an external cache exists.$_wp_using_ext_object_cache = true;}// If cache supports reset, reset instead of init if already initialized.// Reset signals to the cache that global IDs have changed and it may need to update keys// and cleanup caches.if ( !$first_init && function_exists('wp_cache_reset') )wp_cache_reset();elsewp_cache_init();if ( function_exists( 'wp_cache_add_global_groups' ) ) {wp_cache_add_global_groups( array( 'users', 'userlogins', 'usermeta', 'user_meta', 'site-transient', 'site-options', 'site-lookup', 'blog-lookup', 'blog-details', 'rss', 'global-posts' ) );wp_cache_add_non_persistent_groups( array( 'comment', 'counts', 'plugins' ) );}}/** * Redirects to the installer if WordPress is not installed. * * Dies with an error message when multisite is enabled. * * @access private * @since 3.0.0 */function wp_not_installed() {if ( is_multisite() ) {if ( ! is_blog_installed() && ! defined( 'WP_INSTALLING' ) )wp_die( __( 'The site you have requested is not installed properly. Please contact the system administrator.' ) );} elseif ( ! is_blog_installed() && false === strpos( $_SERVER['PHP_SELF'], 'install.php' ) && !defined( 'WP_INSTALLING' ) ) {$link = wp_guess_url() . '/wp-admin/install.php';require( ABSPATH . WPINC . '/kses.php' );require( ABSPATH . WPINC . '/pluggable.php' );require( ABSPATH . WPINC . '/formatting.php' );wp_redirect( $link );die();}}/** * Returns array of must-use plugin files to be included in global scope. * * The default directory is wp-content/mu-plugins. To change the default directory * manually, define <code>WPMU_PLUGIN_DIR</code> and <code>WPMU_PLUGIN_URL</code> * in wp-config.php. * * @access private * @since 3.0.0 * @return array Files to include */function wp_get_mu_plugins() {$mu_plugins = array();if ( !is_dir( WPMU_PLUGIN_DIR ) )return $mu_plugins;if ( ! $dh = opendir( WPMU_PLUGIN_DIR ) )return $mu_plugins;while ( ( $plugin = readdir( $dh ) ) !== false ) {if ( substr( $plugin, -4 ) == '.php' )$mu_plugins[] = WPMU_PLUGIN_DIR . '/' . $plugin;}closedir( $dh );sort( $mu_plugins );return $mu_plugins;}/** * Returns array of plugin files to be included in global scope. * * The default directory is wp-content/plugins. To change the default directory * manually, define <code>WP_PLUGIN_DIR</code> and <code>WP_PLUGIN_URL</code> * in wp-config.php. * * @access private * @since 3.0.0 * @return array Files to include */function wp_get_active_and_valid_plugins() {$plugins = array();$active_plugins = (array) get_option( 'active_plugins', array() );// Check for hacks file if the option is enabledif ( get_option( 'hack_file' ) && file_exists( ABSPATH . 'my-hacks.php' ) ) {_deprecated_file( 'my-hacks.php', '1.5' );array_unshift( $plugins, ABSPATH . 'my-hacks.php' );}if ( empty( $active_plugins ) || defined( 'WP_INSTALLING' ) )return $plugins;$network_plugins = is_multisite() ? wp_get_active_network_plugins() : false;foreach ( $active_plugins as $plugin ) {if ( ! validate_file( $plugin ) // $plugin must validate as file&& '.php' == substr( $plugin, -4 ) // $plugin must end with '.php'&& file_exists( WP_PLUGIN_DIR . '/' . $plugin ) // $plugin must exist// not already included as a network plugin&& ( ! $network_plugins || ! in_array( WP_PLUGIN_DIR . '/' . $plugin, $network_plugins ) ))$plugins[] = WP_PLUGIN_DIR . '/' . $plugin;}return $plugins;}/** * Sets internal encoding using mb_internal_encoding(). * * In most cases the default internal encoding is latin1, which is of no use, * since we want to use the mb_ functions for utf-8 strings. * * @access private * @since 3.0.0 */function wp_set_internal_encoding() {if ( function_exists( 'mb_internal_encoding' ) ) {if ( !@mb_internal_encoding( get_option( 'blog_charset' ) ) )mb_internal_encoding( 'UTF-8' );}}/** * Add magic quotes to $_GET, $_POST, $_COOKIE, and $_SERVER. * * Also forces $_REQUEST to be $_GET + $_POST. If $_SERVER, $_COOKIE, * or $_ENV are needed, use those superglobals directly. * * @access private * @since 3.0.0 */function wp_magic_quotes() {// If already slashed, strip.if ( get_magic_quotes_gpc() ) {$_GET    = stripslashes_deep( $_GET    );$_POST   = stripslashes_deep( $_POST   );$_COOKIE = stripslashes_deep( $_COOKIE );}// Escape with wpdb.$_GET    = add_magic_quotes( $_GET    );$_POST   = add_magic_quotes( $_POST   );$_COOKIE = add_magic_quotes( $_COOKIE );$_SERVER = add_magic_quotes( $_SERVER );// Force REQUEST to be GET + POST.$_REQUEST = array_merge( $_GET, $_POST );}/** * Runs just before PHP shuts down execution. * * @access private * @since 1.2.0 */function shutdown_action_hook() {do_action( 'shutdown' );wp_cache_close();}/** * Copy an object. * * @since 2.7.0 * @deprecated 3.2 * * @param object $object The object to clone * @return object The cloned object */function wp_clone( $object ) {// Use parens for clone to accommodate PHP 4.  See #17880return clone( $object );}/** * Whether the current request is for a network or blog admin page * * Does not inform on whether the user is an admin! Use capability checks to * tell if the user should be accessing a section or not. * * @since 1.5.1 * * @return bool True if inside WordPress administration pages. */function is_admin() {if ( defined( 'WP_ADMIN' ) )return WP_ADMIN;return false;}/** * Whether the current request is for a blog admin screen /wp-admin/ * * Does not inform on whether the user is a blog admin! Use capability checks to * tell if the user should be accessing a section or not. * * @since 3.1.0 * * @return bool True if inside WordPress network administration pages. */function is_blog_admin() {if ( defined( 'WP_BLOG_ADMIN' ) )return WP_BLOG_ADMIN;return false;}/** * Whether the current request is for a network admin screen /wp-admin/network/ * * Does not inform on whether the user is a network admin! Use capability checks to * tell if the user should be accessing a section or not. * * @since 3.1.0 * * @return bool True if inside WordPress network administration pages. */function is_network_admin() {if ( defined( 'WP_NETWORK_ADMIN' ) )return WP_NETWORK_ADMIN;return false;}/** * Whether the current request is for a user admin screen /wp-admin/user/ * * Does not inform on whether the user is an admin! Use capability checks to * tell if the user should be accessing a section or not. * * @since 3.1.0 * * @return bool True if inside WordPress user administration pages. */function is_user_admin() {if ( defined( 'WP_USER_ADMIN' ) )return WP_USER_ADMIN;return false;}/** * Whether Multisite support is enabled * * @since 3.0.0 * * @return bool True if multisite is enabled, false otherwise. */function is_multisite() {if ( defined( 'MULTISITE' ) )return MULTISITE;if ( defined( 'SUBDOMAIN_INSTALL' ) || defined( 'VHOST' ) || defined( 'SUNRISE' ) )return true;return false;}?>

这个文件都是一些函数。
wp_unregister_GLOBALS()，wp_fix_server_vars()，wp_check_php_mysql_versions()，wp_favicon_request()，wp_maintenance()，timer_start()，timer_stop()，wp_debug_mode(),wp_set_lang_dir(),require_wp_db(),wp_set_wpdb_vars(),wp_start_object_cache(),wp_not_installed(), wp_get_mu_plugins(), wp_get_active_and_valid_plugins(), wp_set_internal_encoding(), wp_magic_quotes(), shutdown_action_hook(), wp_clone( $object ), is_admin(), is_blog_admin(),is_network_admin(), is_user_admin(), is_multisite(), 一共24个函数。其中有几个常用的函数，比如is_admin()。