friendica/include/config.php

<?php

/**
 * @file include/config.php
 * 
 *  @brief Arbitrary configuration storage
 * Note:
 * Please do not store booleans - convert to 0/1 integer values
 * The get_?config() functions return boolean false for keys that are unset,
 * and this could lead to subtle bugs.
 *
 * There are a few places in the code (such as the admin panel) where boolean
 * configurations need to be fixed as of 10/08/2011.
 */

/**
 * @brief Loads all configuration values of family into a cached storage.
 *
 * All configuration values of the system are stored in global cache
 * which is available under the global variable $a->config
 *
 * @param string $family
 *  The category of the configuration value
 * @return void
 */
function load_config($family) {
	global $a;

	$r = q("SELECT `v`, `k` FROM `config` WHERE `cat` = '%s'", dbesc($family));
	if(count($r)) {
		foreach($r as $rr) {
			$k = $rr['k'];
			if ($family === 'config') {
				$a->config[$k] = $rr['v'];
			} else {
				$a->config[$family][$k] = $rr['v'];
			}
		}
	} else if ($family != 'config') {
		// Negative caching
		$a->config[$family] = "!<unset>!";
	}
}

/**
 * @brief Get a particular user's config variable given the category name
 * ($family) and a key.
 *
 * Get a particular config value from the given category ($family)
 * and the $key from a cached storage in $a->config[$uid].
 * $instore is only used by the set_config function
 * to determine if the key already exists in the DB
 * If a key is found in the DB but doesn't exist in
 * local config cache, pull it into the cache so we don't have
 * to hit the DB again for this item.
 *
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to query
 * @param boolean $instore Determines if the key already exists in the DB
 * @return mixed Stored value or false if it does not exist
 */
function get_config($family, $key, $instore = false) {

	global $a;

	if(! $instore) {
		// Looking if the whole family isn't set
		if(isset($a->config[$family])) {
			if($a->config[$family] === '!<unset>!') {
				return false;
			}
		}

		if(isset($a->config[$family][$key])) {
			if($a->config[$family][$key] === '!<unset>!') {
				return false;
			}
			return $a->config[$family][$key];
		}
	}

	// If APC is enabled then fetch the data from there, else try XCache
	/*if (function_exists("apc_fetch") AND function_exists("apc_exists"))
		if (apc_exists($family."|".$key)) {
			$val = apc_fetch($family."|".$key);
			$a->config[$family][$key] = $val;

			if ($val === '!<unset>!')
				return false;
			else
				return $val;
		}
	elseif (function_exists("xcache_fetch") AND function_exists("xcache_isset"))
		if (xcache_isset($family."|".$key)) {
			$val = xcache_fetch($family."|".$key);
			$a->config[$family][$key] = $val;

			if ($val === '!<unset>!')
				return false;
			else
				return $val;
		}
	*/

	$ret = q("SELECT `v` FROM `config` WHERE `cat` = '%s' AND `k` = '%s' LIMIT 1",
		dbesc($family),
		dbesc($key)
	);
	if(count($ret)) {
		// manage array value
		$val = (preg_match("|^a:[0-9]+:{.*}$|s", $ret[0]['v'])?unserialize( $ret[0]['v']):$ret[0]['v']);
		$a->config[$family][$key] = $val;

		// If APC is enabled then store the data there, else try XCache
		/*if (function_exists("apc_store"))
			apc_store($family."|".$key, $val, 600);
		elseif (function_exists("xcache_set"))
			xcache_set($family."|".$key, $val, 600);*/

		return $val;
	}
	else {
		$a->config[$family][$key] = '!<unset>!';

		// If APC is enabled then store the data there, else try XCache
		/*if (function_exists("apc_store"))
			apc_store($family."|".$key, '!<unset>!', 600);
		elseif (function_exists("xcache_set"))
			xcache_set($family."|".$key, '!<unset>!', 600);*/
	}
	return false;
}

/**
 * @brief Sets a configuration value for system config
 *
 * Stores a config value ($value) in the category ($family) under the key ($key)
 * for the user_id $uid.
 *
 * Note: Please do not store booleans - convert to 0/1 integer values!
 *
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to set
 * @param string $value
 *  The value to store
 * @return mixed Stored $value or false if the database update failed
 */
function set_config($family,$key,$value) {
	global $a;

	// If $a->config[$family] has been previously set to '!<unset>!', then
	// $a->config[$family][$key] will evaluate to $a->config[$family][0], and
	// $a->config[$family][$key] = $value will be equivalent to
	// $a->config[$family][0] = $value[0] (this causes infuriating bugs),
	// so unset the family before assigning a value to a family's key
	if($a->config[$family] === '!<unset>!')
		unset($a->config[$family]);

	// manage array value
	$dbvalue = (is_array($value)?serialize($value):$value);
	$dbvalue = (is_bool($dbvalue) ? intval($dbvalue) : $dbvalue);
	if(get_config($family,$key,true) === false) {
		$a->config[$family][$key] = $value;
		$ret = q("INSERT INTO `config` ( `cat`, `k`, `v` ) VALUES ( '%s', '%s', '%s' ) ",
			dbesc($family),
			dbesc($key),
			dbesc($dbvalue)
		);
		if($ret)
			return $value;
		return $ret;
	}

	$ret = q("UPDATE `config` SET `v` = '%s' WHERE `cat` = '%s' AND `k` = '%s'",
		dbesc($dbvalue),
		dbesc($family),
		dbesc($key)
	);

	$a->config[$family][$key] = $value;

	// If APC is enabled then store the data there, else try XCache
	/*if (function_exists("apc_store"))
		apc_store($family."|".$key, $value, 600);
	elseif (function_exists("xcache_set"))
		xcache_set($family."|".$key, $value, 600);*/

	if($ret)
		return $value;
	return $ret;
}

/**
 * @brief Deletes the given key from the system configuration.
 *
 * Removes the configured value from the stored cache in $a->config
 * and removes it from the database.
 *
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to delete
 * @return mixed
 */
function del_config($family,$key) {

	global $a;
	if(x($a->config[$family],$key))
		unset($a->config[$family][$key]);
	$ret = q("DELETE FROM `config` WHERE `cat` = '%s' AND `k` = '%s'",
		dbesc($family),
		dbesc($key)
	);
	// If APC is enabled then delete the data from there, else try XCache
	/*if (function_exists("apc_delete"))
		apc_delete($family."|".$key);
	elseif (function_exists("xcache_unset"))
		xcache_unset($family."|".$key);*/

	return $ret;
}

/**
 * @brief Loads all configuration values of a user's config family into a cached storage.
 *
 * All configuration values of the given user are stored in global cache
 * which is available under the global variable $a->config[$uid].
 *
 * @param string $uid
 *  The user_id
 * @param string $family
 *  The category of the configuration value
 * @return void
 */
function load_pconfig($uid,$family) {
	global $a;
	$r = q("SELECT `v`,`k` FROM `pconfig` WHERE `cat` = '%s' AND `uid` = %d",
		dbesc($family),
		intval($uid)
	);
	if(count($r)) {
		foreach($r as $rr) {
			$k = $rr['k'];
			$a->config[$uid][$family][$k] = $rr['v'];
		}
	} else if ($family != 'config') {
		// Negative caching
		$a->config[$uid][$family] = "!<unset>!";
	}
}

/**
 * @brief Get a particular user's config variable given the category name
 * ($family) and a key.
 *
 * Get a particular user's config value from the given category ($family)
 * and the $key from a cached storage in $a->config[$uid].
 *
 * @param string $uid
 *  The user_id
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to query
 * @param boolean $instore
 * Determines if the key already exists in the DB
 * @return mixed Stored value or false if it does not exist
 */
function get_pconfig($uid,$family, $key, $instore = false) {

	global $a;

	if(! $instore) {
		// Looking if the whole family isn't set
		if(isset($a->config[$uid][$family])) {
			if($a->config[$uid][$family] === '!<unset>!') {
				return false;
			}
		}

		if(isset($a->config[$uid][$family][$key])) {
			if($a->config[$uid][$family][$key] === '!<unset>!') {
				return false;
			}
			return $a->config[$uid][$family][$key];
		}
	}

	// If APC is enabled then fetch the data from there, else try XCache
	/*if (function_exists("apc_fetch") AND function_exists("apc_exists"))
		if (apc_exists($uid."|".$family."|".$key)) {
			$val = apc_fetch($uid."|".$family."|".$key);
			$a->config[$uid][$family][$key] = $val;

			if ($val === '!<unset>!')
				return false;
			else
				return $val;
		}
	elseif (function_exists("xcache_get") AND function_exists("xcache_isset"))
		if (xcache_isset($uid."|".$family."|".$key)) {
			$val = xcache_get($uid."|".$family."|".$key);
			$a->config[$uid][$family][$key] = $val;

			if ($val === '!<unset>!')
				return false;
			else
				return $val;
		}*/


	$ret = q("SELECT `v` FROM `pconfig` WHERE `uid` = %d AND `cat` = '%s' AND `k` = '%s' LIMIT 1",
		intval($uid),
		dbesc($family),
		dbesc($key)
	);

	if(count($ret)) {
		$val = (preg_match("|^a:[0-9]+:{.*}$|s", $ret[0]['v'])?unserialize( $ret[0]['v']):$ret[0]['v']);
		$a->config[$uid][$family][$key] = $val;

		// If APC is enabled then store the data there, else try XCache
		/*if (function_exists("apc_store"))
			apc_store($uid."|".$family."|".$key, $val, 600);
		elseif (function_exists("xcache_set"))
			xcache_set($uid."|".$family."|".$key, $val, 600);*/

		return $val;
	}
	else {
		$a->config[$uid][$family][$key] = '!<unset>!';

		// If APC is enabled then store the data there, else try XCache
		/*if (function_exists("apc_store"))
			apc_store($uid."|".$family."|".$key, '!<unset>!', 600);
		elseif (function_exists("xcache_set"))
			xcache_set($uid."|".$family."|".$key, '!<unset>!', 600);*/
	}
	return false;
}

/**
 * @brief Sets a configuration value for a user
 *
 * Stores a config value ($value) in the category ($family) under the key ($key)
 * for the user_id $uid.
 *
 * @note Please do not store booleans - convert to 0/1 integer values!
 *
 * @param string $uid
 *  The user_id
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to set
 * @param string $value
 *  The value to store
 * @return mixed Stored $value or false
 */
function set_pconfig($uid,$family,$key,$value) {

	global $a;

	// manage array value
	$dbvalue = (is_array($value)?serialize($value):$value);

	if(get_pconfig($uid,$family,$key,true) === false) {
		$a->config[$uid][$family][$key] = $value;
		$ret = q("INSERT INTO `pconfig` ( `uid`, `cat`, `k`, `v` ) VALUES ( %d, '%s', '%s', '%s' ) ",
			intval($uid),
			dbesc($family),
			dbesc($key),
			dbesc($dbvalue)
		);
		if($ret) 
			return $value;
		return $ret;
	}
	$ret = q("UPDATE `pconfig` SET `v` = '%s' WHERE `uid` = %d AND `cat` = '%s' AND `k` = '%s'",
		dbesc($dbvalue),
		intval($uid),
		dbesc($family),
		dbesc($key)
	);

	$a->config[$uid][$family][$key] = $value;

	// If APC is enabled then store the data there, else try XCache
	/*if (function_exists("apc_store"))
		apc_store($uid."|".$family."|".$key, $value, 600);
	elseif (function_exists("xcache_set"))
		xcache_set($uid."|".$family."|".$key, $value, 600);*/


	if($ret)
		return $value;
	return $ret;
}

/**
 * @brief Deletes the given key from the users's configuration.
 *
 * Removes the configured value from the stored cache in $a->config[$uid]
 * and removes it from the database.
 *
 * @param string $uid The user_id
 * @param string $family
 *  The category of the configuration value
 * @param string $key
 *  The configuration key to delete
 * @return mixed
 */
function del_pconfig($uid,$family,$key) {

	global $a;
	if(x($a->config[$uid][$family],$key))
		unset($a->config[$uid][$family][$key]);
	$ret = q("DELETE FROM `pconfig` WHERE `uid` = %d AND `cat` = '%s' AND `k` = '%s'",
		intval($uid),
		dbesc($family),
		dbesc($key)
	);
	return $ret;
}