[conntrack-tools,4/4] conntrackd: introduce RequestResync option

diff --git a/conntrackd.conf.5 b/conntrackd.conf.5
index 4a4f2e2..6ac0fb6 100644
--- a/conntrackd.conf.5
+++ b/conntrackd.conf.5
@@ -195,6 +195,15 @@  messages are directly sent through the dedicated link.
 This option is set off by default.
 
 .TP
+.BI "RequestResync <seconds>"
+Request the other node a complete resync. This should help resolve
+synchronization more easily if they happen in your environment.
+
+Example: RequestResync 60
+
+This option is set off by default.
+
+.TP
 .BI "DisableExternalCache <on|off>"
 Same as in \fBFTFW\fP mode.
 
diff --git a/include/conntrackd.h b/include/conntrackd.h
index 27e43db..4cfb373 100644
--- a/include/conntrackd.h
+++ b/include/conntrackd.h
@@ -111,6 +111,7 @@  struct ct_conf {
 	int event_iterations_limit;
 	int systemd;
 	int running_mode;
+	int request_resync;
 	struct {
 		int error_queue_length;
 	} channelc;
diff --git a/include/resync.h b/include/resync.h
index 5986600..75cd7dd 100644
--- a/include/resync.h
+++ b/include/resync.h
@@ -3,5 +3,6 @@ 
 
 void resync_req(void);
 void resync_send(int (*do_cache_to_tx)(void *data1, void *data2));
+void resync_run_init(void);
 
 #endif /*_RESYNC_H_ */
diff --git a/src/read_config_lex.l b/src/read_config_lex.l
index a378269..664b818 100644
--- a/src/read_config_lex.l
+++ b/src/read_config_lex.l
@@ -136,6 +136,7 @@  notrack		[N|n][O|o][T|t][R|r][A|a][C|c][K|k]
 "ExpectMax"			{ return T_HELPER_EXPECT_MAX; }
 "ExpectTimeout"			{ return T_HELPER_EXPECT_TIMEOUT; }
 "Systemd"			{ return T_SYSTEMD; }
+"RequestResync"			{ return T_REQUEST_RESYNC; }
 
 {is_on}			{ return T_ON; }
 {is_off}		{ return T_OFF; }
diff --git a/src/read_config_yy.y b/src/read_config_yy.y
index 2c08d4e..0509bd3 100644
--- a/src/read_config_yy.y
+++ b/src/read_config_yy.y
@@ -81,7 +81,7 @@  enum {
 %token T_OPTIONS T_TCP_WINDOW_TRACKING T_EXPECT_SYNC
 %token T_HELPER T_HELPER_QUEUE_NUM T_HELPER_QUEUE_LEN T_HELPER_POLICY
 %token T_HELPER_EXPECT_TIMEOUT T_HELPER_EXPECT_MAX
-%token T_SYSTEMD
+%token T_SYSTEMD T_REQUEST_RESYNC
 
 %token <string> T_IP T_PATH_VAL
 %token <val> T_NUMBER
@@ -777,6 +777,7 @@  sync_mode_notrack_line: timeout
 		      | purge
 		      | disable_internal_cache
 		      | disable_external_cache
+		      | request_resync
 		      ;
 
 disable_internal_cache: T_DISABLE_INTERNAL_CACHE T_ON
@@ -804,6 +805,11 @@  resend_queue_size: T_RESEND_QUEUE_SIZE T_NUMBER
 	conf.resend_queue_size = $2;
 };
 
+request_resync: T_REQUEST_RESYNC T_NUMBER
+{
+	conf.request_resync = $2;
+};
+
 window_size: T_WINDOWSIZE T_NUMBER
 {
 	conf.window_size = $2;
diff --git a/src/resync.c b/src/resync.c
index dbb2b6f..4310d6b 100644
--- a/src/resync.c
+++ b/src/resync.c
@@ -23,6 +23,9 @@ 
 #include "queue_tx.h"
 #include "resync.h"
 #include "cache.h"
+#include "alarm.h"
+
+static struct alarm_block	resync_run_alarm;
 
 void resync_req(void)
 {
@@ -38,3 +41,21 @@  void resync_send(int (*do_cache_to_tx)(void *data1, void *data2))
 	cache_iterate(STATE(mode)->internal->exp.data,
 		      NULL, do_cache_to_tx);
 }
+
+static void resync_run(struct alarm_block *a, void *data)
+{
+	resync_req();
+	add_alarm(&resync_run_alarm, CONFIG(request_resync), 0);
+}
+
+void resync_run_init(void)
+{
+	if (CONFIG(request_resync) == 0)
+		return;
+
+	dlog(LOG_NOTICE, "setting up atomatic resync requests every %d "
+	     "seconds", CONFIG(request_resync));
+
+	init_alarm(&resync_run_alarm, NULL,  resync_run);
+	add_alarm(&resync_run_alarm, CONFIG(request_resync), 0);
+}
diff --git a/src/run.c b/src/run.c
index 1fe6cba..4ff2186 100644
--- a/src/run.c
+++ b/src/run.c
@@ -31,6 +31,7 @@ 
 #include "date.h"
 #include "internal.h"
 #include "systemd.h"
+#include "resync.h"
 
 #include <errno.h>
 #include <signal.h>
@@ -284,6 +285,8 @@  init(void)
 #endif
 	time(&STATE(stats).daemon_start_time);
 
+	resync_run_init();
+
 	dlog(LOG_NOTICE, "initialization completed");
 
 	return 0;