procd: rework trigger handling

Open/close triggers array around service_triggers call to make using
multiple triggers easier to deal with.
The API was quite confusing, because some functions contained implicit
trigger open/close calls and some didn't.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

package/system/procd/files/procd.sh

@@ -72,7 +72,9 @@ _procd_open_service() {
 
 _procd_close_service() {
 	json_close_object
+	_procd_open_trigger
 	service_triggers
+	_procd_close_trigger
 	_procd_ubus_call set
 }
 
@@ -117,13 +119,27 @@ _procd_open_instance() {
 }
 
 _procd_open_trigger() {
+	let '_procd_trigger_open = _procd_trigger_open + 1'
+	[ "$_procd_trigger_open" -gt 1 ] && return
 	json_add_array "triggers"
 }
 
+_procd_close_trigger() {
+	let '_procd_trigger_open = _procd_trigger_open - 1'
+	[ "$_procd_trigger_open" -lt 1 ] || return
+	json_close_array
+}
+
 _procd_open_validate() {
+	json_select ..
 	json_add_array "validate"
 }
 
+_procd_close_validate() {
+	json_close_array
+	json_select triggers
+}
+
 _procd_add_jail() {
 	json_add_object "jail"
 	json_add_string name "$1"
@@ -331,14 +347,6 @@ _procd_close_instance() {
 	json_close_object
 }
 
-_procd_close_trigger() {
-	json_close_array
-}
-
-_procd_close_validate() {
-	json_close_array
-}
-
 _procd_add_instance() {
 	_procd_open_instance
 	_procd_set_param command "$@"