From: Arran Cudbard-Bell <a.cudbardb@freeradius.org>
Date: Sat, 28 Aug 2021 16:43:34 +0000 (-0500)
Subject: Add pid reaping function
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7e7c59279a786a6ad9f2c4470ea4cf6f41807d2e;p=thirdparty%2Ffreeradius-server.git

Add pid reaping function
---

diff --git a/src/lib/util/event.c b/src/lib/util/event.c
index b37a48a928e..5dfc3ae54e0 100644
--- a/src/lib/util/event.c
+++ b/src/lib/util/event.c
@@ -1679,6 +1679,32 @@ int _fr_event_pid_wait(NDEBUG_LOCATION_ARGS
 	return 0;
 }
 
+/** Does the actual reaping of PIDs
+ *
+ */
+static void _fr_event_pid_reap_cb(UNUSED fr_event_list_t *el, pid_t pid, int status, UNUSED void *uctx)
+{
+	waitpid(pid, &status, WNOHANG);	/* Don't block the process if there's a logic error somewhere */
+}
+
+/** Asynchronously wait for a PID to exit, then reap it
+ *
+ * This is intended to be used when we no longer care about a process
+ * exiting, but we still want to clean up its state so we don't have
+ * zombie processes sticking around.
+ *
+ * @param[in] el	to use to reap the process.
+ * @param[in] pid	to reap.
+ * @return
+ *	- -1 if we couldn't find the process or it has already exited/been reaped.
+ *      - 0 on success (we setup a process handler).
+ */
+int _fr_event_pid_reap(NDEBUG_LOCATION_ARGS fr_event_list_t *el, pid_t pid)
+{
+	return _fr_event_pid_wait(NDEBUG_LOCATION_VALS NULL, el, NULL, pid, _fr_event_pid_reap_cb, NULL);
+}
+
+
 /** Add a user callback to the event list.
  *
  * @param[in] el	Containing the timer events.
diff --git a/src/lib/util/event.h b/src/lib/util/event.h
index babb65b5d11..03ea604a532 100644
--- a/src/lib/util/event.h
+++ b/src/lib/util/event.h
@@ -257,6 +257,10 @@ int		_fr_event_pid_wait(NDEBUG_LOCATION_ARGS
 				   CC_HINT(nonnull(NDEBUG_LOCATION_NONNULL(2)));
 #define		fr_event_pid_wait(...) _fr_event_pid_wait(NDEBUG_LOCATION_EXP __VA_ARGS__)
 
+int		_fr_event_pid_reap(NDEBUG_LOCATION_ARGS fr_event_list_t *el, pid_t pid)
+				   CC_HINT(nonnull(NDEBUG_LOCATION_NONNULL(1)));
+#define		fr_event_pid_reap(...) _fr_event_pid_reap(NDEBUG_LOCATION_EXP __VA_ARGS__)
+
 int		fr_event_timer_run(fr_event_list_t *el, fr_time_t *when);
 
 uintptr_t      	fr_event_user_insert(fr_event_list_t *el, fr_event_user_handler_t user, void *uctx) CC_HINT(nonnull(1,2));