web/wp-includes/cron.php
branchwordpress
changeset 109 03b0d1493584
child 132 4d4862461b8d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/wp-includes/cron.php	Wed Dec 23 17:55:33 2009 +0000
@@ -0,0 +1,397 @@
+<?php
+/**
+ * WordPress CRON API
+ *
+ * @package WordPress
+ */
+
+/**
+ * Schedules a hook to run only once.
+ *
+ * Schedules a hook which will be executed once by the Wordpress actions core at
+ * a time which you specify. The action will fire off when someone visits your
+ * WordPress site, if the schedule time has passed.
+ *
+ * @since 2.1.0
+ * @link http://codex.wordpress.org/Function_Reference/wp_schedule_single_event
+ *
+ * @param int $timestamp Timestamp for when to run the event.
+ * @param string $hook Action hook to execute when cron is run.
+ * @param array $args Optional. Arguments to pass to the hook's callback function.
+ */
+function wp_schedule_single_event( $timestamp, $hook, $args = array()) {
+	// don't schedule a duplicate if there's already an identical event due in the next 10 minutes
+	$next = wp_next_scheduled($hook, $args);
+	if ( $next && $next <= $timestamp + 600 )
+		return;
+
+	$crons = _get_cron_array();
+	$key = md5(serialize($args));
+	$crons[$timestamp][$hook][$key] = array( 'schedule' => false, 'args' => $args );
+	uksort( $crons, "strnatcasecmp" );
+	_set_cron_array( $crons );
+}
+
+/**
+ * Schedule a periodic event.
+ *
+ * Schedules a hook which will be executed by the WordPress actions core on a
+ * specific interval, specified by you. The action will trigger when someone
+ * visits your WordPress site, if the scheduled time has passed.
+ *
+ * Valid values for the recurrence are hourly, daily and twicedaily.  These can
+ * be extended using the cron_schedules filter in wp_get_schedules().
+ *
+ * @since 2.1.0
+ *
+ * @param int $timestamp Timestamp for when to run the event.
+ * @param string $recurrence How often the event should recur.
+ * @param string $hook Action hook to execute when cron is run.
+ * @param array $args Optional. Arguments to pass to the hook's callback function.
+ * @return bool|null False on failure, null when complete with scheduling event.
+ */
+function wp_schedule_event( $timestamp, $recurrence, $hook, $args = array()) {
+	$crons = _get_cron_array();
+	$schedules = wp_get_schedules();
+	$key = md5(serialize($args));
+	if ( !isset( $schedules[$recurrence] ) )
+		return false;
+	$crons[$timestamp][$hook][$key] = array( 'schedule' => $recurrence, 'args' => $args, 'interval' => $schedules[$recurrence]['interval'] );
+	uksort( $crons, "strnatcasecmp" );
+	_set_cron_array( $crons );
+}
+
+/**
+ * Reschedule a recurring event.
+ *
+ * @since 2.1.0
+ *
+ * @param int $timestamp Timestamp for when to run the event.
+ * @param string $recurrence How often the event should recur.
+ * @param string $hook Action hook to execute when cron is run.
+ * @param array $args Optional. Arguments to pass to the hook's callback function.
+ * @return bool|null False on failure. Null when event is rescheduled.
+ */
+function wp_reschedule_event( $timestamp, $recurrence, $hook, $args = array()) {
+	$crons = _get_cron_array();
+	$schedules = wp_get_schedules();
+	$key = md5(serialize($args));
+	$interval = 0;
+
+	// First we try to get it from the schedule
+	if ( 0 == $interval )
+		$interval = $schedules[$recurrence]['interval'];
+	// Now we try to get it from the saved interval in case the schedule disappears
+	if ( 0 == $interval )
+		$interval = $crons[$timestamp][$hook][$key]['interval'];
+	// Now we assume something is wrong and fail to schedule
+	if ( 0 == $interval )
+		return false;
+
+	$now = time();
+
+    if ( $timestamp >= $now )
+        $timestamp = $now + $interval;
+    else
+        $timestamp = $now + ($interval - (($now - $timestamp) % $interval));
+
+	wp_schedule_event( $timestamp, $recurrence, $hook, $args );
+}
+
+/**
+ * Unschedule a previously scheduled cron job.
+ *
+ * The $timestamp and $hook parameters are required, so that the event can be
+ * identified.
+ *
+ * @since 2.1.0
+ *
+ * @param int $timestamp Timestamp for when to run the event.
+ * @param string $hook Action hook, the execution of which will be unscheduled.
+ * @param array $args Arguments to pass to the hook's callback function.
+ * Although not passed to a callback function, these arguments are used
+ * to uniquely identify the scheduled event, so they should be the same
+ * as those used when originally scheduling the event.
+ */
+function wp_unschedule_event( $timestamp, $hook, $args = array() ) {
+	$crons = _get_cron_array();
+	$key = md5(serialize($args));
+	unset( $crons[$timestamp][$hook][$key] );
+	if ( empty($crons[$timestamp][$hook]) )
+		unset( $crons[$timestamp][$hook] );
+	if ( empty($crons[$timestamp]) )
+		unset( $crons[$timestamp] );
+	_set_cron_array( $crons );
+}
+
+/**
+ * Unschedule all cron jobs attached to a specific hook.
+ *
+ * @since 2.1.0
+ *
+ * @param string $hook Action hook, the execution of which will be unscheduled.
+ * @param mixed $args,... Optional. Event arguments.
+ */
+function wp_clear_scheduled_hook( $hook ) {
+	$args = array_slice( func_get_args(), 1 );
+
+	while ( $timestamp = wp_next_scheduled( $hook, $args ) )
+		wp_unschedule_event( $timestamp, $hook, $args );
+}
+
+/**
+ * Retrieve the next timestamp for a cron event.
+ *
+ * @since 2.1.0
+ *
+ * @param string $hook Action hook to execute when cron is run.
+ * @param array $args Optional. Arguments to pass to the hook's callback function.
+ * @return bool|int The UNIX timestamp of the next time the scheduled event will occur.
+ */
+function wp_next_scheduled( $hook, $args = array() ) {
+	$crons = _get_cron_array();
+	$key = md5(serialize($args));
+	if ( empty($crons) )
+		return false;
+	foreach ( $crons as $timestamp => $cron ) {
+		if ( isset( $cron[$hook][$key] ) )
+			return $timestamp;
+	}
+	return false;
+}
+
+/**
+ * Send request to run cron through HTTP request that doesn't halt page loading.
+ *
+ * @since 2.1.0
+ *
+ * @return null Cron could not be spawned, because it is not needed to run.
+ */
+function spawn_cron( $local_time = 0 ) {
+
+	if ( !$local_time )
+		$local_time = time();
+
+	if ( defined('DOING_CRON') || isset($_GET['doing_wp_cron']) )
+		return;
+
+	/*
+	 * do not even start the cron if local server timer has drifted
+	 * such as due to power failure, or misconfiguration
+	 */
+	$timer_accurate = check_server_timer( $local_time );
+	if ( !$timer_accurate )
+		return;
+
+	/*
+	* multiple processes on multiple web servers can run this code concurrently
+	* try to make this as atomic as possible by setting doing_cron switch
+	*/
+	$flag = get_transient('doing_cron');
+
+	if ( $flag > $local_time + 10*60 )
+		$flag = 0;
+
+	// don't run if another process is currently running it or more than once every 60 sec.
+	if ( $flag + 60 > $local_time )
+		return;
+
+	//sanity check
+	$crons = _get_cron_array();
+	if ( !is_array($crons) )
+		return;
+
+	$keys = array_keys( $crons );
+	if ( isset($keys[0]) && $keys[0] > $local_time )
+		return;
+
+	if ( defined('ALTERNATE_WP_CRON') && ALTERNATE_WP_CRON ) {
+		if ( !empty($_POST) || defined('DOING_AJAX') )
+			return;
+
+		set_transient( 'doing_cron', $local_time );
+
+		ob_start();
+		wp_redirect( add_query_arg('doing_wp_cron', '', stripslashes($_SERVER['REQUEST_URI'])) );
+		echo ' ';
+
+		// flush any buffers and send the headers
+		while ( @ob_end_flush() );
+		flush();
+
+		@include_once(ABSPATH . 'wp-cron.php');
+		return;
+	}
+
+	set_transient( 'doing_cron', $local_time );
+
+	$cron_url = get_option( 'siteurl' ) . '/wp-cron.php?doing_wp_cron';
+	wp_remote_post( $cron_url, array('timeout' => 0.01, 'blocking' => false, 'sslverify' => apply_filters('https_local_ssl_verify', true)) );
+}
+
+/**
+ * Run scheduled callbacks or spawn cron for all scheduled events.
+ *
+ * @since 2.1.0
+ *
+ * @return null When doesn't need to run Cron.
+ */
+function wp_cron() {
+
+	// Prevent infinite loops caused by lack of wp-cron.php
+	if ( strpos($_SERVER['REQUEST_URI'], '/wp-cron.php') !== false || ( defined('DISABLE_WP_CRON') && DISABLE_WP_CRON ) )
+		return;
+
+	if ( false === $crons = _get_cron_array() )
+		return;
+
+	$local_time = time();
+	$keys = array_keys( $crons );
+	if ( isset($keys[0]) && $keys[0] > $local_time )
+		return;
+
+	$schedules = wp_get_schedules();
+	foreach ( $crons as $timestamp => $cronhooks ) {
+		if ( $timestamp > $local_time ) break;
+		foreach ( (array) $cronhooks as $hook => $args ) {
+			if ( isset($schedules[$hook]['callback']) && !call_user_func( $schedules[$hook]['callback'] ) )
+				continue;
+			spawn_cron( $local_time );
+			break 2;
+		}
+	}
+}
+
+/**
+ * Retrieve supported and filtered Cron recurrences.
+ *
+ * The supported recurrences are 'hourly' and 'daily'. A plugin may add more by
+ * hooking into the 'cron_schedules' filter. The filter accepts an array of
+ * arrays. The outer array has a key that is the name of the schedule or for
+ * example 'weekly'. The value is an array with two keys, one is 'interval' and
+ * the other is 'display'.
+ *
+ * The 'interval' is a number in seconds of when the cron job should run. So for
+ * 'hourly', the time is 3600 or 60*60. For weekly, the value would be
+ * 60*60*24*7 or 604800. The value of 'interval' would then be 604800.
+ *
+ * The 'display' is the description. For the 'weekly' key, the 'display' would
+ * be <code>__('Once Weekly')</code>.
+ *
+ * For your plugin, you will be passed an array. you can easily add your
+ * schedule by doing the following.
+ * <code>
+ * // filter parameter variable name is 'array'
+ *	$array['weekly'] = array(
+ *		'interval' => 604800,
+ *		'display' => __('Once Weekly')
+ *	);
+ * </code>
+ *
+ * @since 2.1.0
+ *
+ * @return array
+ */
+function wp_get_schedules() {
+	$schedules = array(
+		'hourly' => array( 'interval' => 3600, 'display' => __('Once Hourly') ),
+		'twicedaily' => array( 'interval' => 43200, 'display' => __('Twice Daily') ),
+		'daily' => array( 'interval' => 86400, 'display' => __('Once Daily') ),
+	);
+	return array_merge( apply_filters( 'cron_schedules', array() ), $schedules );
+}
+
+/**
+ * Retrieve Cron schedule for hook with arguments.
+ *
+ * @since 2.1.0
+ *
+ * @param string $hook Action hook to execute when cron is run.
+ * @param array $args Optional. Arguments to pass to the hook's callback function.
+ * @return string|bool False, if no schedule. Schedule on success.
+ */
+function wp_get_schedule($hook, $args = array()) {
+	$crons = _get_cron_array();
+	$key = md5(serialize($args));
+	if ( empty($crons) )
+		return false;
+	foreach ( $crons as $timestamp => $cron ) {
+		if ( isset( $cron[$hook][$key] ) )
+			return $cron[$hook][$key]['schedule'];
+	}
+	return false;
+}
+
+//
+// Private functions
+//
+
+/**
+ * Retrieve cron info array option.
+ *
+ * @since 2.1.0
+ * @access private
+ *
+ * @return array CRON info array.
+ */
+function _get_cron_array()  {
+	$cron = get_option('cron');
+	if ( ! is_array($cron) )
+		return false;
+
+	if ( !isset($cron['version']) )
+		$cron = _upgrade_cron_array($cron);
+
+	unset($cron['version']);
+
+	return $cron;
+}
+
+/**
+ * Updates the CRON option with the new CRON array.
+ *
+ * @since 2.1.0
+ * @access private
+ *
+ * @param array $cron Cron info array from {@link _get_cron_array()}.
+ */
+function _set_cron_array($cron) {
+	$cron['version'] = 2;
+	update_option( 'cron', $cron );
+}
+
+/**
+ * Upgrade a Cron info array.
+ *
+ * This function upgrades the Cron info array to version 2.
+ *
+ * @since 2.1.0
+ * @access private
+ *
+ * @param array $cron Cron info array from {@link _get_cron_array()}.
+ * @return array An upgraded Cron info array.
+ */
+function _upgrade_cron_array($cron) {
+	if ( isset($cron['version']) && 2 == $cron['version'])
+		return $cron;
+
+	$new_cron = array();
+
+	foreach ( (array) $cron as $timestamp => $hooks) {
+		foreach ( (array) $hooks as $hook => $args ) {
+			$key = md5(serialize($args['args']));
+			$new_cron[$timestamp][$hook][$key] = $args;
+		}
+	}
+
+	$new_cron['version'] = 2;
+	update_option( 'cron', $new_cron );
+	return $new_cron;
+}
+
+// stub for checking server timer accuracy, using outside standard time sources
+function check_server_timer( $local_time ) {
+	return true;
+}
+
+?>