From: Maria Matejka <mq@ucw.cz>
Date: Fri, 24 Nov 2023 11:19:44 +0000 (+0100)
Subject: Channels now can have external obstacles temporarily blocking their shutdown
X-Git-Tag: v3.0.0~317
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f0da632b3c406c6c39a582e7a353737d90d16117;p=thirdparty%2Fbird.git

Channels now can have external obstacles temporarily blocking their shutdown
---

diff --git a/nest/proto.c b/nest/proto.c
index 72d94a282..6427afcd2 100644
--- a/nest/proto.c
+++ b/nest/proto.c
@@ -745,7 +745,7 @@ channel_check_stopped(struct channel *c)
   switch (c->channel_state)
   {
     case CS_STOP:
-      if (!EMPTY_LIST(c->roa_subscriptions) || c->out_req.hook || c->refeed_req.hook || c->in_req.hook || c->reload_req.hook)
+      if (c->obstacles || !EMPTY_LIST(c->roa_subscriptions) || c->out_req.hook || c->refeed_req.hook || c->in_req.hook || c->reload_req.hook)
 	return;
 
       channel_set_state(c, CS_DOWN);
@@ -753,7 +753,7 @@ channel_check_stopped(struct channel *c)
 
       break;
     case CS_PAUSE:
-      if (!EMPTY_LIST(c->roa_subscriptions) || c->out_req.hook || c->refeed_req.hook || c->reload_req.hook)
+      if (c->obstacles || !EMPTY_LIST(c->roa_subscriptions) || c->out_req.hook || c->refeed_req.hook || c->reload_req.hook)
 	return;
 
       channel_set_state(c, CS_START);
@@ -763,6 +763,19 @@ channel_check_stopped(struct channel *c)
   DBG("%s.%s: Channel requests/hooks stopped (in state %s)\n", c->proto->name, c->name, c_states[c->channel_state]);
 }
 
+void
+channel_add_obstacle(struct channel *c)
+{
+  c->obstacles++;
+}
+
+void
+channel_del_obstacle(struct channel *c)
+{
+  if (!--c->obstacles)
+    channel_check_stopped(c);
+}
+
 void
 channel_import_stopped(struct rt_import_request *req)
 {
diff --git a/nest/protocol.h b/nest/protocol.h
index 9b8b837d1..4c983ffc9 100644
--- a/nest/protocol.h
+++ b/nest/protocol.h
@@ -605,6 +605,8 @@ struct channel {
   u8 gr_lock;				/* Graceful restart mechanism should wait for this channel */
   u8 gr_wait;				/* Route export to channel is postponed until graceful restart */
 
+  u32 obstacles;			/* External obstacles remaining before cleanup */
+
   btime last_state_change;		/* Time of last state transition */
 
   struct rt_export_request reload_req;	/* Feeder for import reload */
@@ -692,6 +694,9 @@ void channel_set_state(struct channel *c, uint state);
 void channel_schedule_reload(struct channel *c, struct channel_import_request *cir);
 int channel_import_request_prefilter(struct channel_import_request *cir_head, const net_addr *n);
 
+void channel_add_obstacle(struct channel *c);
+void channel_del_obstacle(struct channel *c);
+
 static inline void channel_init(struct channel *c) { channel_set_state(c, CS_START); }
 static inline void channel_open(struct channel *c) { channel_set_state(c, CS_UP); }
 static inline void channel_close(struct channel *c) { channel_set_state(c, CS_STOP); }