Enhance SIGINT handler.

child.c

@@ -1,6 +1,6 @@
 /* -*-pgsql-c-*- */
 /*
- * $Header: /cvsroot/pgpool/pgpool-II/child.c,v 1.36 2009/11/14 13:22:32 t-ishii Exp $
+ * $Header: /cvsroot/pgpool/pgpool-II/child.c,v 1.37 2009/12/02 14:19:56 t-ishii Exp $
  *
  * pgpool: a language independent connection pool server for PostgreSQL
  * written by Tatsuo Ishii
@@ -74,7 +74,7 @@ static void connection_count_down(void);
 /*
  * non 0 means SIGTERM(smart shutdown) or SIGINT(fast shutdown) has arrived
  */
-static int exit_request;
+volatile sig_atomic_t exit_request = 0;
 
 static int idle;		/* non 0 means this child is in idle state */
 static int accepted = 0;
@@ -174,11 +174,7 @@ void do_child(int unix_fd, int inet_fd)
 		StartupPacket *sp;
 
 		/* pgpool stop request already sent? */
-		if (exit_request)
-		{
-			die(0);
-			child_exit(0);
-		}
+		check_stop_request();
 
 		idle = 1;
 		accepted = 0;
@@ -1211,37 +1207,30 @@ static POOL_CONNECTION_POOL *connect_backend(StartupPacket *sp, POOL_CONNECTION
 }
 
 /*
- * signal handler for SIGINT and SIGQUUT
+ * signal handler for SIGTERM, SIGINT and SIGQUUT
  */
 static RETSIGTYPE die(int sig)
 {
-	exit_request = 1;
+	pool_debug("child received shutdown request signal %d", sig);
 
-	pool_debug("child receives shutdown request signal %d", sig);
+	exit_request = sig;
 
 	switch (sig)
 	{
 		case SIGTERM:	/* smart shutdown */
 			if (idle == 0)
 			{
 				pool_debug("child receives smart shutdown request but it's not in idle state");
-				return;
 			}
 			break;
 
 		case SIGINT:	/* fast shutdown */
 		case SIGQUIT:	/* immediate shutdown */
-			child_exit(0);
 			break;
 		default:
+			pool_error("die() received unknown signal: %d", sig);
 			break;
 	}
-
-	/*
-	 * child_exit() does this. So we don't need it.
-	 * send_frontend_exits();
-	 */
-	child_exit(0);
 }
 
 /*
@@ -1862,3 +1851,22 @@ static RETSIGTYPE reload_config_handler(int sig)
 {
 	got_sighup = 1;
 }
+
+/*
+ * Exit myself if SIGTERM, SIGINT or SIGQUIT has been sent
+ */
+void check_stop_request(void)
+{
+    /*
+	 * If smart shutdown was requested but we are not in idle state,
+	 * do not exit
+	 */
+	if (exit_request == SIGTERM && idle == 0)
+		return;
+
+	if (exit_request)
+	{
+		reset_variables();
+		child_exit(0);
+	}
+}

pool.h

@@ -1,7 +1,7 @@
 /* -*-pgsql-c-*- */
 /*
  *
- * $Header: /cvsroot/pgpool/pgpool-II/pool.h,v 1.45 2009/11/15 08:27:35 t-ishii Exp $
+ * $Header: /cvsroot/pgpool/pgpool-II/pool.h,v 1.46 2009/12/02 14:19:56 t-ishii Exp $
  *
  * pgpool: a language independent connection pool server for PostgreSQL 
  * written by Tatsuo Ishii
@@ -650,6 +650,7 @@ extern void finish_recovery(void);
 extern void pool_set_nonblock(int fd);
 extern void pool_unset_nonblock(int fd);
 extern void cancel_request(CancelPacket *sp);
+extern void check_stop_request(void);
 
 /* pool_process_query.c */
 void free_select_result(POOL_SELECT_RESULT *result);

pool_process_query.c

@@ -1,6 +1,6 @@
 /* -*-pgsql-c-*- */
 /*
- * $Header: /cvsroot/pgpool/pgpool-II/pool_process_query.c,v 1.176 2009/11/29 11:56:59 t-ishii Exp $
+ * $Header: /cvsroot/pgpool/pgpool-II/pool_process_query.c,v 1.177 2009/12/02 14:19:56 t-ishii Exp $
  *
  * pgpool: a language independent connection pool server for PostgreSQL
  * written by Tatsuo Ishii
@@ -150,6 +150,8 @@ POOL_STATUS pool_process_query(POOL_CONNECTION *frontend,
 
 		}
 
+		check_stop_request();
+
 		/*
 		 * if all backends do not have any pending data in the
 		 * receiving data cache, then issue select(2) to wait for new