Avoid deadlock when activating signals.

Fixes bug 3048812.

Based on patch by Nicholas Marriott.

diff --git a/signal.c b/signal.c
index 3c474d33a413ef41ef90a63f3f3141e1a9d10868..1954223d6638002868955c8287962d53c203d201 100644 (file)
--- a/signal.c
+++ b/signal.c
@@ -89,8 +89,11 @@ evsig_cb(evutil_socket_t fd, short what, void *arg)
        (void)arg; /* Suppress "unused variable" warning. */
 
        n = recv(fd, signals, sizeof(signals), 0);
-       if (n == -1)
-               event_sock_err(1, fd, "%s: read", __func__);
+       if (n == -1) {
+               int err = evutil_socket_geterror(fd);
+               if (! EVUTIL_ERR_RW_RETRIABLE(err))
+                       event_sock_err(1, fd, "%s: recv", __func__);
+       }
 }
 
 int
@@ -121,6 +124,7 @@ evsig_init(struct event_base *base)
        memset(&base->sig.evsigcaught, 0, sizeof(sig_atomic_t)*NSIG);
 
        evutil_make_socket_nonblocking(base->sig.ev_signal_pair[0]);
+       evutil_make_socket_nonblocking(base->sig.ev_signal_pair[1]);
 
        event_assign(&base->sig.ev_signal, base, base->sig.ev_signal_pair[1],
                EV_READ | EV_PERSIST, evsig_cb, &base->sig.ev_signal);