lib: add sigevent_check api

Add an api that blocks application-handled signals (SIGINT,
SIGTERM, e.g.) then tests whether any signals have been received.
This helps to manage a race between signal reception and the poll
call in the main event loop.

Signed-off-by: Mark Stapp <mjs@voltanet.io>

1 files changed, 9 insertions, 0 deletions

diff --git a/lib/sigevent.h b/lib/sigevent.h
index a0ad88fcaa..4a39b22889 100644
--- a/lib/sigevent.h
+++ b/lib/sigevent.h
@@ -48,6 +48,15 @@ struct quagga_signal_t {
 extern void signal_init(struct thread_master *m, int sigc,
 			struct quagga_signal_t *signals);
 
+
+/*
+ * Check whether any signals have been received and are pending. This is done
+ * with the application's key signals blocked. The complete set of signals
+ * is returned in 'setp', so the caller can restore them when appropriate.
+ * If there are pending signals, returns 'true', 'false' otherwise.
+ */
+bool frr_sigevent_check(sigset_t *setp);
+
 /* check whether there are signals to handle, process any found */
 extern int quagga_sigevent_process(void);