From 5ab36719f1c100afe483c58d7fcb15f1fa231d2a Mon Sep 17 00:00:00 2001
From: "Nicholas J. Kain" <nicholas@kain.us>
Date: Fri, 25 Dec 2015 02:44:54 -0500
Subject: [PATCH] If a fd closes unexpectedly in epoll, print error and exit
 with failure.

Before the exit code would be success and no error message would print,
and it required a bit of control flow tracing to determine what would
actually happen.

No direct functional change (unless the supervising process cares about
the return code of ndhc on exit).
---
 src/ndhc.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/ndhc.c b/src/ndhc.c
index bee0b8e..56f29f0 100644
--- a/src/ndhc.c
+++ b/src/ndhc.c
@@ -306,20 +306,20 @@ static void do_ndhc_work(void)
             int fd = events[i].data.fd;
             if (fd == cs.signalFd) {
                 if (!(events[i].events & EPOLLIN))
-                    return;
+                    suicide("signalfd closed unexpectedly");
                 sev_signal = signal_dispatch();
             } else if (fd == cs.listenFd) {
                 if (!(events[i].events & EPOLLIN))
-                    return;
+                    suicide("listenfd closed unexpectedly");
                 sev_dhcp = dhcp_packet_get(&cs, &dhcp_packet, &dhcp_msgtype,
                                            &dhcp_srcaddr);
             } else if (fd == cs.arpFd) {
                 if (!(events[i].events & EPOLLIN))
-                    return;
+                    suicide("arpfd closed unexpectedly");
                 sev_arp = arp_packet_get(&cs);
             } else if (fd == cs.nlFd) {
                 if (!(events[i].events & EPOLLIN))
-                    return;
+                    suicide("nlfd closed unexpectedly");
                 sev_nl = nl_event_get(&cs);
             } else if (fd == ifchStream[0]) {
                 if (events[i].events & (EPOLLHUP|EPOLLERR|EPOLLRDHUP))
@@ -329,7 +329,7 @@ static void do_ndhc_work(void)
                     exit(EXIT_FAILURE);
             } else if (fd == cs.rfkillFd && client_config.enable_rfkill) {
                 if (!(events[i].events & EPOLLIN))
-                    return;
+                    suicide("rfkillfd closed unexpectedly");
                 sev_rfk = rfkill_get(&cs, 1, client_config.rfkillIdx);
             } else
                 suicide("epoll_wait: unknown fd");