From: Jo-Philipp Wich <jo@mein.io>
Date: Tue, 13 Dec 2016 16:27:13 +0000 (+0100)
Subject: service: add reload_signal property
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=f800ecf860addd4fc7f1acde76a9adbd4b1f50e7;p=project%2Fprocd.git

service: add reload_signal property

Introduce a new optional property "reload_signal" which - if set - instructs
procd to not terminate and restart supervised processes upon changes, but to
send them a kill() signal instead.

This is useful for services which fully support native config reload upon
receipt of a signal.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
---

diff --git a/service/instance.c b/service/instance.c
index 8838049..018db3c 100644
--- a/service/instance.c
+++ b/service/instance.c
@@ -54,6 +54,7 @@ enum {
 	INSTANCE_ATTR_TRACE,
 	INSTANCE_ATTR_SECCOMP,
 	INSTANCE_ATTR_PIDFILE,
+	INSTANCE_ATTR_RELOADSIG,
 	__INSTANCE_ATTR_MAX
 };
 
@@ -77,6 +78,7 @@ static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
 	[INSTANCE_ATTR_TRACE] = { "trace", BLOBMSG_TYPE_BOOL },
 	[INSTANCE_ATTR_SECCOMP] = { "seccomp", BLOBMSG_TYPE_STRING },
 	[INSTANCE_ATTR_PIDFILE] = { "pidfile", BLOBMSG_TYPE_STRING },
+	[INSTANCE_ATTR_RELOADSIG] = { "reload_signal", BLOBMSG_TYPE_INT32 },
 };
 
 enum {
@@ -551,6 +553,12 @@ instance_restart(struct service_instance *in)
 {
 	if (!in->proc.pending)
 		return;
+
+	if (in->reload_signal) {
+		kill(in->proc.pid, in->reload_signal);
+		return;
+	}
+
 	in->halt = false;
 	in->restart = true;
 	kill(in->proc.pid, SIGTERM);
@@ -854,6 +862,9 @@ instance_config_parse(struct service_instance *in)
 			in->pidfile = pidfile;
 	}
 
+	if (tb[INSTANCE_ATTR_RELOADSIG])
+		in->reload_signal = blobmsg_get_u32(tb[INSTANCE_ATTR_RELOADSIG]);
+
 	if (!in->trace && tb[INSTANCE_ATTR_JAIL])
 		in->has_jail = instance_jail_parse(in, tb[INSTANCE_ATTR_JAIL]);
 
@@ -1021,6 +1032,9 @@ void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 		blobmsg_close_table(b, e);
 	}
 
+	if (in->reload_signal)
+		blobmsg_add_u32(b, "reload_signal", in->reload_signal);
+
 	if (in->respawn) {
 		void *r = blobmsg_open_table(b, "respawn");
 		blobmsg_add_u32(b, "threshold", in->respawn_threshold);
diff --git a/service/instance.h b/service/instance.h
index 6f95a2a..3cc2009 100644
--- a/service/instance.h
+++ b/service/instance.h
@@ -49,6 +49,7 @@ struct service_instance {
 	bool restart;
 	bool respawn;
 	int respawn_count;
+	int reload_signal;
 	struct timespec start;
 
 	bool trace;