From 4d05bf9359058896163bec3c649daa87bc266675 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Sun, 7 Mar 2021 13:26:56 +0100
Subject: [PATCH] Mark affected services as dirty if their rdeps are dirty

Provided a configuration that looks like this:

ospfd.conf:
    service [2345] <!pid/zebra> log ospfd -A 127.0.0.1 -u root -g root -- OSPF daemon

zebra.conf:
    service [2345] <!> log zebra -A 127.0.0.1 -u root -g root -- Zebra Routing daemon

If zebra.conf is changed, we restart it when `initctl reload` is issued.

This change ensures that ospfd is also restarted, because ospfd depends
on zebra, we must restart it too.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 src/cond-w.c  | 20 --------------------
 src/conf.c    |  2 ++
 src/service.c | 32 ++++++++++++++++++++++++++++++++
 src/service.h |  1 +
 src/svc.h     | 20 ++++++++++++++++++++
 5 files changed, 55 insertions(+), 20 deletions(-)

diff --git a/src/cond-w.c b/src/cond-w.c
index e5f7456e..daa90d08 100644
--- a/src/cond-w.c
+++ b/src/cond-w.c
@@ -162,26 +162,6 @@ int cond_set_path(const char *path, enum cond_state new)
 	return new != old;
 }
 
-/* Has condition in configuration and cond is allowed? */
-static int svc_has_cond(svc_t *svc)
-{
-	if (!svc->cond[0])
-		return 0;
-
-	switch (svc->type) {
-	case SVC_TYPE_SERVICE:
-	case SVC_TYPE_TASK:
-	case SVC_TYPE_RUN:
-	case SVC_TYPE_SYSV:
-		return 1;
-
-	default:
-		break;
-	}
-
-	return 0;
-}
-
 static void cond_update(const char *name)
 {
 	svc_t *svc, *iter = NULL;
diff --git a/src/conf.c b/src/conf.c
index f34cf34a..8cb91d78 100644
--- a/src/conf.c
+++ b/src/conf.c
@@ -697,6 +697,8 @@ int conf_reload(void)
 
 	globfree(&gl);
 
+	/* Mark any reverse deps as chenaged. */
+	service_update_rdeps();
 done:
 	/* Drop record of all .conf changes */
 	drop_changes();
diff --git a/src/service.c b/src/service.c
index e56adee7..cf04fa56 100644
--- a/src/service.c
+++ b/src/service.c
@@ -1250,6 +1250,38 @@ void service_monitor(pid_t lost, int status)
 	sm_step(&sm);
 }
 
+static void svc_mark_affected(char *cond)
+{
+	svc_t *svc, *iter = NULL;
+
+	for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0)) {
+		if (!svc_has_cond(svc))
+			continue;
+
+		if (cond_affects(cond, svc->cond))
+			svc_mark_dirty(svc);
+	}
+}
+
+/*
+ * Called on conf_reload() to update service reverse dependencies.
+ * E.g., if ospfd depends on zebra and the zebra Finit conf has
+ * changed, we need to mark the ospfd Finit conf as changed too.
+ */
+void service_update_rdeps(void)
+{
+	svc_t *svc, *iter = NULL;
+
+	for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0)) {
+		char cond[MAX_COND_LEN];
+
+		if (!svc_is_changed(svc))
+			continue;
+
+		svc_mark_affected(mkcond(svc, cond, sizeof(cond)));
+	}
+}
+
 static void service_retry(svc_t *svc)
 {
 	int timeout;
diff --git a/src/service.h b/src/service.h
index b1ee2081..e9688868 100644
--- a/src/service.h
+++ b/src/service.h
@@ -33,6 +33,7 @@ void      service_unregister     (svc_t *svc);
 
 void      service_runtask_clean  (void);
 void      service_reload_dynamic (void);
+void      service_update_rdeps   (void);
 
 int       service_step           (svc_t *svc);
 void      service_step_all       (int types);
diff --git a/src/svc.h b/src/svc.h
index cf510127..edd38d87 100644
--- a/src/svc.h
+++ b/src/svc.h
@@ -208,6 +208,26 @@ static inline void svc_missing     (svc_t *svc) { if (svc) svc->block = SVC_BLOC
 static inline void svc_restarting  (svc_t *svc) { if (svc) svc->block = SVC_BLOCK_RESTARTING; }
 static inline void svc_crashing    (svc_t *svc) { if (svc) svc->block = SVC_BLOCK_CRASHING; }
 
+/* Has condition in configuration and cond is allowed? */
+static inline int svc_has_cond(svc_t *svc)
+{
+	if (!svc->cond[0])
+		return 0;
+
+	switch (svc->type) {
+	case SVC_TYPE_SERVICE:
+	case SVC_TYPE_TASK:
+	case SVC_TYPE_RUN:
+	case SVC_TYPE_SYSV:
+		return 1;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static inline char *svc_status(svc_t *svc)
 {
 	if (!svc)