CVS commit: src/usr.sbin/ypbind

[David A. Holland]

Module Name:    src
Committed By:   dholland
Date:           Tue Jun 10 17:19:36 UTC 2014

Modified Files:
        src/usr.sbin/ypbind: ypbind.c

Log Message:
Add a SIGHUP handler; upon SIGHUP do an extra nag_servers on any
domain that's in DEAD state. This lets you explicitly rescue ypbind
from its exponential backoff when you know the world's back up.


To generate a diff of this commit:
cvs rdiff -u -r1.96 -r1.97 src/usr.sbin/ypbind/ypbind.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/usr.sbin/ypbind/ypbind.c
diff -u src/usr.sbin/ypbind/ypbind.c:1.96 src/usr.sbin/ypbind/ypbind.c:1.97
--- src/usr.sbin/ypbind/ypbind.c:1.96	Tue Jun 10 17:19:22 2014
+++ src/usr.sbin/ypbind/ypbind.c	Tue Jun 10 17:19:36 2014
@@ -1,4 +1,4 @@
-/*	$NetBSD: ypbind.c,v 1.96 2014/06/10 17:19:22 dholland Exp $	*/
+/*	$NetBSD: ypbind.c,v 1.97 2014/06/10 17:19:36 dholland Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993 Theo de Raadt <dera...@fsa.ca>
@@ -28,7 +28,7 @@
 
 #include <sys/cdefs.h>
 #ifndef LINT
-__RCSID("$NetBSD: ypbind.c,v 1.96 2014/06/10 17:19:22 dholland Exp $");
+__RCSID("$NetBSD: ypbind.c,v 1.97 2014/06/10 17:19:36 dholland Exp $");
 #endif
 
 #include <sys/types.h>
@@ -50,6 +50,7 @@ __RCSID("$NetBSD: ypbind.c,v 1.96 2014/0
 #include <ifaddrs.h>
 #include <limits.h>
 #include <netdb.h>
+#include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -133,6 +134,9 @@ static unsigned long rmtcr_port;
 /* The ypbind service transports */
 static SVCXPRT *udptransp, *tcptransp;
 
+/* set if we get SIGHUP */
+static sig_atomic_t hupped;
+
 ////////////////////////////////////////////////////////////
 // utilities
 
@@ -1533,6 +1537,51 @@ checkwork(void)
 	}
 }
 
+/*
+ * Process a hangup signal.
+ *
+ * Do an extra nag_servers() for any domains that are DEAD. This way
+ * if you know things are back up you can restore service by sending
+ * ypbind a SIGHUP rather than waiting for the timeout period.
+ */
+static void
+dohup(void)
+{
+	struct domain *dom;
+
+	hupped = 0;
+	for (dom = domains; dom != NULL; dom = dom->dom_next) {
+		if (dom->dom_state == DOM_DEAD) {
+			(void)nag_servers(dom);
+		}
+	}
+}
+
+/*
+ * Receive a hangup signal.
+ */
+static void
+hup(int __unused sig)
+{
+	hupped = 1;
+}
+
+/*
+ * Initialize hangup processing.
+ */
+static void
+starthup(void)
+{
+	struct sigaction sa;
+
+	sa.sa_handler = hup;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_RESTART;
+	if (sigaction(SIGHUP, &sa, NULL) == -1) {
+		err(1, "sigaction");
+	}
+}
+
 ////////////////////////////////////////////////////////////
 // main
 
@@ -1615,6 +1664,9 @@ main(int argc, char *argv[])
 	if (lockfd == -1)
 		err(1, "Cannot create %s", _PATH_YPBIND_LOCK);
 
+	/* Accept hangups. */
+	starthup();
+
 	/* Initialize sunrpc stuff. */
 	sunrpc_setup();
 
@@ -1672,12 +1724,24 @@ main(int argc, char *argv[])
 		switch (select(width, &fdsr, NULL, NULL, &tv)) {
 		case 0:
 			/* select timed out - check for timer-based work */
+			if (hupped) {
+				dohup();
+			}
 			checkwork();
 			break;
 		case -1:
-			yp_log(LOG_WARNING, "select: %s", strerror(errno));
+			if (hupped) {
+				dohup();
+			}
+			if (errno != EINTR) {
+				yp_log(LOG_WARNING, "select: %s",
+				       strerror(errno));
+			}
 			break;
 		default:
+			if (hupped) {
+				dohup();
+			}
 			/* incoming of our own; read it */
 			if (FD_ISSET(rpcsock, &fdsr))
 				(void)handle_replies();
@@ -1716,4 +1780,3 @@ main(int argc, char *argv[])
 		}
 	}
 }
-