From d27a5d3212ae1e2ee29f35abf3899a75af26ec71 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Tue, 11 Apr 2017 23:52:32 -0700
Subject: [PATCH] lightningd/lightningd: shutdown subdaemons on exit.
Especially under valgrind, we should give them some time to exit.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
lightningd/lightningd.c | 17 ++++++++++++++++-
lightningd/subd.c | 26 ++++++++++++++++++++++++++
lightningd/subd.h | 10 ++++++++++
3 files changed, 52 insertions(+), 1 deletion(-)
diff --git a/lightningd/lightningd.c b/lightningd/lightningd.c
index 58946d116..1e9be5abc 100644
--- a/lightningd/lightningd.c
+++ b/lightningd/lightningd.c
@@ -197,6 +197,20 @@ void derive_peer_seed(struct lightningd *ld, struct privkey *peer_seed,
ld->peer_counter++;
}
+static void shutdown_subdaemons(struct lightningd *ld)
+{
+ struct peer *p;
+
+ /* Let everyone shutdown cleanly. */
+ subd_shutdown(ld->hsm, 10);
+ subd_shutdown(ld->gossip, 10);
+
+ /* Duplicates are OK: no need to check here. */
+ list_for_each(&ld->peers, p, list)
+ if (p->owner)
+ subd_shutdown(p->owner, 0);
+}
+
int main(int argc, char *argv[])
{
struct lightningd *ld = new_lightningd(NULL);
@@ -250,7 +264,6 @@ int main(int argc, char *argv[])
#if 0
/* Load peers from database. */
db_load_peers(dstate);
-
#endif
for (;;) {
@@ -265,6 +278,8 @@ int main(int argc, char *argv[])
timer_expired(&ld->dstate, expired);
}
+ shutdown_subdaemons(ld);
+
tal_free(ld);
opt_free_table();
return 0;
diff --git a/lightningd/subd.c b/lightningd/subd.c
index 70754b340..cb58f5884 100644
--- a/lightningd/subd.c
+++ b/lightningd/subd.c
@@ -431,6 +431,32 @@ void subd_req_(const tal_t *ctx,
add_req(ctx, sd, type, num_fds_in, replycb, replycb_data);
}
+void subd_shutdown(struct subd *sd, unsigned int seconds)
+{
+ /* Idempotent. */
+ if (!sd->conn)
+ return;
+
+ log_debug(sd->log, "Shutting down");
+
+ /* No finished callback any more. */
+ sd->finished = NULL;
+ /* Don't free sd when we close connection manually. */
+ tal_steal(sd->ld, sd);
+ /* Close connection: should begin shutdown now. */
+ sd->conn = tal_free(sd->conn);
+
+ /* Do we actually want to wait? */
+ while (seconds) {
+ if (waitpid(sd->pid, NULL, WNOHANG) > 0) {
+ tal_del_destructor(sd, destroy_subd);
+ return;
+ }
+ sleep(1);
+ seconds--;
+ }
+}
+
char *opt_subd_debug(const char *optarg, struct lightningd *ld)
{
ld->dev_debug_subdaemon = optarg;
diff --git a/lightningd/subd.h b/lightningd/subd.h
index 6a00a7a55..b1c717686 100644
--- a/lightningd/subd.h
+++ b/lightningd/subd.h
@@ -113,6 +113,16 @@ void subd_req_(const tal_t *ctx,
bool (*replycb)(struct subd *, const u8 *, const int *, void *),
void *replycb_data);
+/**
+ * subd_shutdown - try to politely shut down a subdaemon.
+ * @subd: subd to shutdown.
+ * @seconds: maximum seconds to wait for it to exit.
+ *
+ * This closes the fd to the subdaemon, and gives it a little while to exit.
+ * The @finished callback will never be called.
+ */
+void subd_shutdown(struct subd *subd, unsigned int seconds);
+
char *opt_subd_debug(const char *optarg, struct lightningd *ld);
#endif /* LIGHTNING_LIGHTNINGD_SUBD_H */