drupal/includes/bootstrap.inc

461 lines
12 KiB
PHP

<?php
// $Id$
/**
* @file
* Functions that need to be loaded on every Drupal request.
*/
define('CACHE_PERMANENT', 0);
define('CACHE_TEMPORARY', -1);
/**
* Locate the appropriate configuration file.
*
* Try finding a matching configuration file by stripping the website's
* URI from left to right. If no configuration file is found, return the
* default value, "conf".
*/
function conf_init() {
$uri = $_SERVER['PHP_SELF'];
$file = strtolower(strtr($_SERVER['HTTP_HOST'] . substr($uri, 0, strrpos($uri, '/')), '/:', '..'));
while (strlen($file) > 4) {
if (file_exists('includes/'. $file .'.php')) {
return $file;
}
else {
$file = substr($file, strpos($file, '.') + 1);
}
}
return 'conf';
}
/**
* Load the persistent variable table.
*
* The variable table is composed of values that have been saved in the table
* with variable_set() as well as those explicitly specified in the configuration
* file.
*/
function variable_init($conf = array()) {
// NOTE: caching the variables improves performance with 20% when serving cached pages.
if ($cached = cache_get('variables')) {
$variables = unserialize($cached->data);
}
else {
$result = db_query('SELECT * FROM {variable}');
while ($variable = db_fetch_object($result)) {
$variables[$variable->name] = unserialize($variable->value);
}
cache_set('variables', serialize($variables));
}
foreach ($conf as $name => $value) {
$variables[$name] = $value;
}
return $variables;
}
/**
* Return a persistent variable.
*
* @param $name
* The name of the variable to return.
* @param $default
* The default value to use if this variable has never been set.
* @return
* The value of the variable.
*/
function variable_get($name, $default) {
global $conf;
return isset($conf[$name]) ? $conf[$name] : $default;
}
/**
* Set a persistent variable.
*
* @param $name
* The name of the variable to set.
* @param $value
* The value to set. This can be any PHP data type; these functions take care
* of serialization as necessary.
*/
function variable_set($name, $value) {
global $conf;
db_query("DELETE FROM {variable} WHERE name = '%s'", $name);
db_query("INSERT INTO {variable} (name, value) VALUES ('%s', '%s')", $name, serialize($value));
cache_clear_all('variables');
$conf[$name] = $value;
}
/**
* Unset a persistent variable.
*
* @param $name
* The name of the variable to undefine.
*/
function variable_del($name) {
global $conf;
db_query("DELETE FROM {variable} WHERE name = '%s'", $name);
cache_clear_all('variables');
unset($conf[$name]);
}
/**
* Return data from the persistent cache.
*
* @param $key
* The cache ID of the data to retrieve.
*/
function cache_get($key) {
$cache = db_fetch_object(db_query("SELECT data, created, headers FROM {cache} WHERE cid = '%s'", $key));
if (isset($cache->data)) {
$cache->data = db_decode_blob($cache->data);
return $cache;
}
return 0;
}
/**
* Store data in the persistent cache.
*
* @param $cid
* The cache ID of the data to store.
* @param $data
* The data to store in the cache. Complex data types must be serialized first.
* @param $expire
* One of the following values:
* - CACHE_PERMANENT: Indicates that the item should never be removed unless
* explicitly told to using cache_clear_all() with a cache ID.
* - CACHE_TEMPORARY: Indicates that the item should be removed at the next
* general cache wipe.
* - A Unix timestamp: Indicates that the item should be kept at least until
* the given time, after which it behaves like CACHE_TEMPORARY.
* @param $headers
* A string containing HTTP header information for cached pages.
*/
function cache_set($cid, $data, $expire = CACHE_PERMANENT, $headers = NULL) {
$data = db_encode_blob($data);
db_query("UPDATE {cache} SET data = '%s', created = %d, expire = %d, headers = '%s' WHERE cid = '%s'", $data, time(), $expire, $headers, $cid);
if (!db_affected_rows()) {
@db_query("INSERT INTO {cache} (cid, data, created, expire, headers) VALUES ('%s', '%s', %d, %d, '%s')", $cid, $data, time(), $expire, $headers);
}
}
/**
* Expire data from the cache.
*
* @param $cid
* If set, the cache ID to delete. Otherwise, all cache entries that can expire
* are deleted.
*
* @param $wildcard
* If set to true, the $cid is treated as a substring to match rather than a
* complete ID.
*/
function cache_clear_all($cid = NULL, $wildcard = false) {
if (empty($cid)) {
db_query("DELETE FROM {cache} WHERE expire != %d AND expire < %d", CACHE_PERMANENT, time());
}
else {
if ($wildcard) {
db_query("DELETE FROM {cache} WHERE cid LIKE '%%%s%%'", $cid);
}
else {
db_query("DELETE FROM {cache} WHERE cid = '%s'", $cid);
}
}
}
/**
* Store the current page in the cache.
*/
function page_set_cache() {
global $user, $base_url;
if (!$user->uid && $_SERVER['REQUEST_METHOD'] == 'GET') {
// This will fail in some cases, see page_get_cache() for the explanation.
if ($data = ob_get_contents()) {
if (function_exists('gzencode')) {
if (version_compare(phpversion(), '4.2', '>=')) {
$data = gzencode($data, 9, FORCE_GZIP);
}
else {
$data = gzencode($data, FORCE_GZIP);
}
}
cache_set($base_url . request_uri(), $data, CACHE_TEMPORARY, drupal_get_headers());
}
}
}
/**
* Retrieve the current page from the cache.
*
* Note, we do not serve cached pages when status messages are waiting (from
* a redirected form submission which was completed).
* Because the output handler is not activated, the resulting page will not
* get cached either.
*/
function page_get_cache() {
global $user, $base_url;
$cache = NULL;
if (!$user->uid && $_SERVER['REQUEST_METHOD'] == 'GET' && count(drupal_set_message()) == 0) {
$cache = cache_get($base_url . request_uri());
if (empty($cache)) {
ob_start();
}
}
return $cache;
}
/**
* Set HTTP headers in preparation for a page response.
*/
function drupal_page_header() {
if (variable_get('dev_timer', 0)) {
timer_start();
}
if (variable_get('cache', 0)) {
if ($cache = page_get_cache()) {
// Set default values:
$date = gmdate('D, d M Y H:i:s', $cache->created) .' GMT';
$etag = '"'. md5($date) .'"';
// Check http headers:
$modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? $_SERVER['HTTP_IF_MODIFIED_SINCE'] == $date : NULL;
if (!empty($_SERVER['HTTP_IF_MODIFIED_SINCE']) && ($timestamp = strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE'])) != -1) {
$modified_since = $cache->created <= $timestamp;
}
else {
$modified_since = NULL;
}
$none_match = !empty($_SERVER['HTTP_IF_NONE_MATCH']) ? $_SERVER['HTTP_IF_NONE_MATCH'] == $etag : NULL;
// The type checking here is very important, be careful when changing entries.
if (($modified_since !== NULL || $none_match !== NULL) && $modified_since !== false && $none_match !== false) {
header('HTTP/1.0 304 Not Modified');
exit();
}
// Send appropriate response:
header("Last-Modified: $date");
header("ETag: $etag");
// Determine if the browser accepts gzipped data.
if (@strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') === false && function_exists('gzencode')) {
// Strip the gzip header and run uncompress.
$cache->data = gzinflate(substr(substr($cache->data, 10), 0, -8));
}
elseif (function_exists('gzencode')) {
header('Content-Encoding: gzip');
}
// Send the original request's headers. We send them one after
// another so PHP's header() function can deal with duplicate
// headers.
$headers = explode("\n", $cache->headers);
foreach ($headers as $header) {
header($header);
}
print $cache->data;
// Call all init() and exit() hooks without including all modules.
// Only use those hooks for critical operations.
foreach (bootstrap_hooks() as $hook) {
module_invoke_all($hook);
}
exit();
}
}
}
/**
* Define the critical hooks that force modules to always be loaded.
*/
function bootstrap_hooks() {
return array('init', 'exit');
}
/**
* Unserializes and appends elements from a serialized string.
*
* @param $obj
* The object to which the elements are appended.
* @param $field
* The attribute of $obj whose value should be unserialized.
*/
function drupal_unpack($obj, $field = 'data') {
if ($obj->$field && $data = unserialize($obj->$field)) {
foreach ($data as $key => $value) {
if (!isset($obj->$key)) {
$obj->$key = $value;
}
}
}
return $obj;
}
/**
* Return the URI of the referring page.
*/
function referer_uri() {
if (isset($_SERVER['HTTP_REFERER'])) {
return check_url($_SERVER['HTTP_REFERER']);
}
}
/**
* Return a component of the current Drupal path.
*
* When viewing a page at the path "admin/node/configure", for example, arg(0)
* would return "admin", arg(1) would return "node", and arg(2) would return
* "configure".
*
* Avoid use of this function where possible, as resulting code is hard to read.
* Instead, attempt to use named arguments in menu callback functions. See the
* explanation in menu.inc for how to construct callbacks that take arguments.
*/
function arg($index) {
static $arguments, $q;
if (empty($arguments) || $q != $_GET['q']) {
$arguments = explode('/', $_GET['q']);
}
if (array_key_exists($index, $arguments)) {
return $arguments[$index];
}
}
/**
* Prepare user input for use in a database query, preventing SQL injection attacks.
*/
function check_query($text) {
return addslashes($text);
}
/**
* Prepare user input for use in a URI.
*
* We replace ( and ) with their entity equivalents to prevent XSS attacks.
*/
function check_url($uri) {
$uri = htmlspecialchars($uri, ENT_QUOTES);
$uri = strtr($uri, array('(' => '&040;', ')' => '&041;'));
return $uri;
}
/**
* Since request_uri() is only available on Apache, we generate an
* equivalent using other environment vars.
*/
function request_uri() {
if (isset($_SERVER['REQUEST_URI'])) {
$uri = $_SERVER['REQUEST_URI'];
}
else {
if (isset($_SERVER['argv'])) {
$uri = $_SERVER['PHP_SELF'] .'?'. $_SERVER['argv'][0];
}
else {
$uri = $_SERVER['PHP_SELF'] .'?'. $_SERVER['QUERY_STRING'];
}
}
return check_url($uri);
}
/**
* Begin a global timer, for benchmarking of page execution time.
*/
function timer_start() {
global $timer;
list($usec, $sec) = explode(' ', microtime());
$timer = (float)$usec + (float)$sec;
}
/**
* Log a system message.
*
* @param $type
* The category to which this message belongs.
* @param $message
* The message to store in the log.
* @param $link
* A link to associate with the message.
*/
function watchdog($type, $message, $link = NULL) {
global $user;
db_query("INSERT INTO {watchdog} (uid, type, message, link, location, hostname, timestamp) VALUES (%d, '%s', '%s', '%s', '%s', '%s', %d)", $user->uid, $type, $message, $link, request_uri(), $_SERVER['REMOTE_ADDR'], time());
}
/**
* Set a message for the user to see.
*
* The message is stored in the session so that it can persist through a redirect.
*
* If called with no arguments, this function returns all set messages without
* clearing them.
*/
function drupal_set_message($message = NULL, $type = 'status') {
if (isset($message)) {
if (!isset($_SESSION['messages'])) {
$_SESSION['messages'] = array();
}
if (!isset($_SESSION['messages'][$type])) {
$_SESSION['messages'][$type] = array();
}
$_SESSION['messages'][$type][] = $message;
}
return $_SESSION['messages'];
}
/**
* Return all messages that have been set.
*
* As a side effect, this function clears the message queue.
*/
function drupal_get_messages() {
$messages = drupal_set_message();
$_SESSION['messages'] = array();
return $messages;
}
unset($conf);
$config = conf_init();
include_once "includes/$config.php";
include_once 'includes/database.inc';
include_once 'includes/session.inc';
include_once 'includes/module.inc';
// Initialize configuration variables, using values from conf.php if available.
$conf = variable_init(isset($conf) ? $conf : array());
?>