Acquiring redis lock with existence check.

Signed-off-by: tianhe1986 <w1s2j3229@163.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/system/libraries/Session/drivers/Session_redis_driver.php b/system/libraries/Session/drivers/Session_redis_driver.php
index 2aeb77267..8fc0a45da 100644
--- a/system/libraries/Session/drivers/Session_redis_driver.php
+++ b/system/libraries/Session/drivers/Session_redis_driver.php
@@ -365,7 +365,16 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 				continue;
 			}
 
-			if ( ! $this->_redis->setex($lock_key, 300, time()))
+			if ($ttl === -2)
+			{
+				$set_result = $this->_redis->set($lock_key, time(), array('nx', 'ex' => 300));
+			}
+			else
+			{
+				$set_result = $this->_redis->setex($lock_key, 300, time());
+			}
+
+			if ( ! $set_result)
 			{
 				log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id);
 				return FALSE;