libdaemon: add support for 'exit when idle'

2 files changed, 40 insertions, 18 deletions

diff --git a/libdaemon/server/daemon-server.c b/libdaemon/server/daemon-server.c
index e3759ab2e..4a0d5cf00 100644
--- a/libdaemon/server/daemon-server.c
+++ b/libdaemon/server/daemon-server.c
@@ -80,6 +80,24 @@ static void _exit_handler(int sig __attribute__((unused)))
 
 #  include <stdio.h>
 
+static inline int _is_idle(daemon_state s)
+{
+	return _systemd_activation && s.idle && s.idle->is_idle && !s.threads->next;
+}
+
+static inline struct timeval *_get_timeout(daemon_state s)
+{
+	return (_systemd_activation && s.idle) ? s.idle->ptimeout : NULL;
+}
+
+static inline void _reset_timeout(daemon_state s)
+{
+	if (s.idle) {
+		s.idle->ptimeout->tv_sec = 1;
+		s.idle->ptimeout->tv_usec = 0;
+	}
+}
+
 static int _set_oom_adj(const char *oom_adj_path, int val)
 {
 	FILE *fp;
@@ -508,18 +526,12 @@ static void reap(daemon_state s, int waiting)
 	}
 }
 
-static inline int no_clients(daemon_state s)
-{
-	return s.threads->next == NULL;
-}
-
 void daemon_start(daemon_state s)
 {
-	struct timeval timeout;
+	unsigned timeout_count;
 	int failed = 0;
 	log_state _log = { { 0 } };
 	thread_state _threads = { .next = NULL };
-	unsigned timeout_count = 0;
 
 	/*
 	 * Switch to C locale to avoid reading large locale-archive file used by
@@ -590,12 +602,11 @@ void daemon_start(daemon_state s)
 			failed = 1;
 
 	while (!_shutdown_requested && !failed) {
-		timeout.tv_sec = s.wait_secs;
-		timeout.tv_usec = 0;
+		_reset_timeout(s);
 		fd_set in;
 		FD_ZERO(&in);
 		FD_SET(s.socket_fd, &in);
-		if (select(FD_SETSIZE, &in, NULL, NULL, s.idle ? &timeout : NULL) < 0 && errno != EINTR)
+		if (select(FD_SETSIZE, &in, NULL, NULL, _get_timeout(s)) < 0 && errno != EINTR)
 			perror("select error");
 		if (FD_ISSET(s.socket_fd, &in)) {
 			timeout_count = 0;
@@ -606,8 +617,9 @@ void daemon_start(daemon_state s)
 		reap(s, 0);
 
 		/* s.idle == NULL equals no shutdown on timeout */
-		if (s.idle && no_clients(s) && s.idle(s.private)) {
-			if (++timeout_count >= s.max_timeouts) {
+		if (_is_idle(s)) {
+			DEBUGLOG(&s, "Timeout No. %d", timeout_count + 1);
+			if (++timeout_count >= _get_max_timeouts(s)) {
 				INFO(&s, "Maximum number of timeouts exceeded");
 				break;
 			}
diff --git a/libdaemon/server/daemon-server.h b/libdaemon/server/daemon-server.h
index e507acae1..e6839c9d6 100644
--- a/libdaemon/server/daemon-server.h
+++ b/libdaemon/server/daemon-server.h
@@ -35,8 +35,17 @@ typedef struct {
 	struct buffer buffer;
 } response;
 
+struct timeval;
+
+typedef struct {
+	volatile unsigned is_idle;
+	unsigned max_timeouts;
+	struct timeval *ptimeout;
+} daemon_idle;
+
 struct daemon_state;
 
+
 /*
  * Craft a simple reply, without the need to construct a config_tree. See
  * daemon_send_simple in daemon-client.h for the description of the parameters.
@@ -64,8 +73,6 @@ static inline const char *daemon_request_str(request r, const char *path, const
  */
 typedef response (*handle_request)(struct daemon_state s, client_handle h, request r);
 
-typedef int (*is_idle_fn)(void *private);
-
 typedef struct {
 	uint32_t log_config[32];
 	void *backend_state[32];
@@ -102,10 +109,8 @@ typedef struct daemon_state {
 	struct thread_state *threads;
 	void *private; /* the global daemon state */
 
-	/* timeouts handling */
-	is_idle_fn idle; /* daemon specific function, NULL == no shutdown on timeout */
-	unsigned max_timeouts; /* max allowed timeouts */
-	unsigned wait_secs; /* secs to wait in select loop */
+	/* suport for shutdown on idle */
+	daemon_idle *idle;
 } daemon_state;
 
 typedef struct thread_state {
@@ -173,4 +178,9 @@ void daemon_log_enable(log_state *s, int outlet, int type, int enable);
  */
 int daemon_log_parse(log_state *s, int outlet, const char *types, int enable);
 
+static inline unsigned _get_max_timeouts(daemon_state s)
+{
+	return s.idle ? s.idle->max_timeouts : 0;
+}
+
 #endif