tevent: Add an internal function tevent_epoll_set_panic_fallback().

Can be set externally, allows us to fallback if epoll
fails at runtime.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/lib/tevent/tevent_epoll.c b/lib/tevent/tevent_epoll.c
index c7936d3c94..8a48d1d33d 100644
--- a/lib/tevent/tevent_epoll.c
+++ b/lib/tevent/tevent_epoll.c
@@ -39,9 +39,33 @@ struct epoll_event_context {
 	int epoll_fd;
 
 	pid_t pid;
+
+	bool (*panic_fallback)(struct tevent_context *ev, bool replay);
 };
 
 /*
+  called to set the panic fallback function.
+*/
+_PRIVATE_ bool tevent_epoll_set_panic_fallback(struct tevent_context *ev,
+				bool (*panic_fallback)(struct tevent_context *ev,
+						       bool replay))
+{
+	struct epoll_event_context *epoll_ev;
+
+	if (ev->additional_data == NULL) {
+		return false;
+	}
+
+	epoll_ev = talloc_get_type(ev->additional_data,
+				struct epoll_event_context);
+	if (epoll_ev == NULL) {
+		return false;
+	}
+	epoll_ev->panic_fallback = panic_fallback;
+	return true;
+}
+
+/*
   called when a epoll call fails
 */
 static void epoll_panic(struct epoll_event_context *epoll_ev,