Merge pull request #91 from merrill-oakland/sessionlocks

More granular session locking support

Author: Mikko Koppanen

memcached.ini

@@ -12,6 +12,18 @@ memcached.sess_locking = On
 ; the default is 150000
 memcached.sess_lock_wait = 150000
 
+; The maximum time, in seconds, to wait for a session lock
+; before timing out.
+; Setting to 0 results in default behavior, which is to
+; use max_execution_time.
+memcached.sess_lock_max_wait = 0;
+
+; The time, in seconds, before a lock should release itself.
+; Setting to 0 results in the default behaviour, which is to
+; use the memcached.sess_lock_max_wait setting. If that is
+; also 0, max_execution_time will be used.
+memcached.sess_lock_expire = 0;
+
 ; memcached session key prefix
 ; valid values are strings less than 219 bytes long
 ; the default value is "memc.sess.key."

php_memcached.c

@@ -295,6 +295,8 @@ PHP_INI_BEGIN()
 	STD_PHP_INI_ENTRY("memcached.sess_consistent_hash",	"0",		PHP_INI_ALL, OnUpdateBool,		sess_consistent_hash_enabled,	zend_php_memcached_globals,	php_memcached_globals)
 	STD_PHP_INI_ENTRY("memcached.sess_binary",		"0",		PHP_INI_ALL, OnUpdateBool,		sess_binary_enabled,	zend_php_memcached_globals,	php_memcached_globals)
 	STD_PHP_INI_ENTRY("memcached.sess_lock_wait",		"150000",	PHP_INI_ALL, OnUpdateLongGEZero,sess_lock_wait,			zend_php_memcached_globals,	php_memcached_globals)
+	STD_PHP_INI_ENTRY("memcached.sess_lock_max_wait",		"0",	PHP_INI_ALL, OnUpdateLongGEZero, sess_lock_max_wait,			zend_php_memcached_globals,	php_memcached_globals)
+	STD_PHP_INI_ENTRY("memcached.sess_lock_expire",		"0",	PHP_INI_ALL, OnUpdateLongGEZero, sess_lock_expire,			zend_php_memcached_globals,	php_memcached_globals)
 	STD_PHP_INI_ENTRY("memcached.sess_prefix",		"memc.sess.key.",	PHP_INI_ALL, OnUpdateString, sess_prefix,		zend_php_memcached_globals,	php_memcached_globals)
 
 	STD_PHP_INI_ENTRY("memcached.sess_number_of_replicas",	"0",	PHP_INI_ALL, OnUpdateLongGEZero,	sess_number_of_replicas,	zend_php_memcached_globals,	php_memcached_globals)
@@ -3155,6 +3157,8 @@ static void php_memc_init_globals(zend_php_memcached_globals *php_memcached_glob
 	MEMC_G(sess_remove_failed_enabled) = 0;
 	MEMC_G(sess_prefix) = NULL;
 	MEMC_G(sess_lock_wait) = 0;
+	MEMC_G(sess_lock_max_wait) = 0;
+	MEMC_G(sess_lock_expire) = 0;
 	MEMC_G(sess_locked) = 0;
 	MEMC_G(sess_lock_key) = NULL;
 	MEMC_G(sess_lock_key_len) = 0;

php_memcached.h

@@ -62,6 +62,8 @@ ZEND_BEGIN_MODULE_GLOBALS(php_memcached)
 #ifdef HAVE_MEMCACHED_SESSION
 	zend_bool sess_locking_enabled;
 	long  sess_lock_wait;
+	long  sess_lock_max_wait;
+	long  sess_lock_expire;
 	char* sess_prefix;
 	zend_bool sess_locked;
 	char* sess_lock_key;

php_memcached_session.c

@@ -49,20 +49,25 @@ static int php_memc_sess_lock(memcached_st *memc, const char *key TSRMLS_DC)
 	int lock_key_len = 0;
 	unsigned long attempts;
 	long write_retry_attempts = 0;
-	long lock_maxwait;
+	long lock_maxwait = MEMC_G(sess_lock_max_wait);
 	long lock_wait = MEMC_G(sess_lock_wait);
+	long lock_expire = MEMC_G(sess_lock_expire);
 	time_t expiration;
 	memcached_return status;
 	/* set max timeout for session_start = max_execution_time.  (c) Andrei Darashenka, Richter & Poweleit GmbH */
-
-	lock_maxwait = zend_ini_long(ZEND_STRS("max_execution_time"), 0);
 	if (lock_maxwait <= 0) {
-		lock_maxwait = MEMC_SESS_LOCK_EXPIRATION;
+		lock_maxwait = zend_ini_long(ZEND_STRS("max_execution_time"), 0);
+		if (lock_maxwait <= 0) {
+			lock_maxwait = MEMC_SESS_LOCK_EXPIRATION;
+		}
 	}
 	if (lock_wait == 0) {
 		lock_wait = MEMC_SESS_DEFAULT_LOCK_WAIT;
 	}
-	expiration  = time(NULL) + lock_maxwait + 1;
+	if (lock_expire <= 0) {
+		lock_expire = lock_maxwait;
+	}
+	expiration  = time(NULL) + lock_expire + 1;
 	attempts = (unsigned long)((1000000.0 / lock_wait) * lock_maxwait);
 
 	/* Set the number of write retry attempts to the number of replicas times the number of attempts to remove a server */