Don't hold the mutex for more than 20 seconds.

Jeremy.

1 files changed, 32 insertions, 4 deletions

diff --git a/source/lib/messages.c b/source/lib/messages.c
index b745cbaf8bd..7d0da4b158b 100644
--- a/source/lib/messages.c
+++ b/source/lib/messages.c
@@ -464,6 +464,17 @@ BOOL message_send_all(TDB_CONTEXT *conn_tdb, int msg_type,
 	return True;
 }
 
+static VOLATILE sig_atomic_t gotalarm;
+
+/***************************************************************
+ Signal function to tell us we timed out.
+****************************************************************/
+
+static void gotalarm_sig(void)
+{
+	gotalarm = 1;
+}
+
 /**
  * Lock the messaging tdb based on a string - this is used as a primitive
  * form of mutex between smbd instances. 
@@ -471,16 +482,33 @@ BOOL message_send_all(TDB_CONTEXT *conn_tdb, int msg_type,
  * @param name A string identifying the name of the mutex.
  */
 
-BOOL message_named_mutex(const char *name)
+BOOL message_named_mutex(char *name, unsigned int timeout)
 {
 	TDB_DATA key;
+	int ret;
 
-	if (!message_init()) return False;
+	if (!message_init())
+		return False;
 
 	key.dptr = name;
 	key.dsize = strlen(name)+1;
 
-	return (tdb_chainlock(tdb, key) == 0);
+	if (timeout) {
+		gotalarm = 0;
+		CatchSignal(SIGALRM, SIGNAL_CAST gotalarm_sig);
+		alarm(timeout);
+	}
+
+	ret = tdb_chainlock(tdb, key);
+
+	if (timeout) {
+		alarm(0);
+		CatchSignal(SIGALRM, SIGNAL_CAST SIG_IGN);
+		if (gotalarm)
+			return False;
+	}
+
+	return (ret == 0);
 }
 
 /**
@@ -489,7 +517,7 @@ BOOL message_named_mutex(const char *name)
  * @param name A string identifying the name of the mutex.
  */
 
-void message_named_mutex_release(const char *name)
+void message_named_mutex_release(char *name)
 {
 	TDB_DATA key;