From: Simon Schubert <2@0x2c.org>
Date: Mon, 28 Jun 2010 22:49:53 +0000 (+0200)
Subject: catch SIGHUP so that sleeps can be interrupted by the user
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=247523d6ea29cfb4df93a2fa197bb7b0f0ca8c0f;p=people%2Fms%2Fdma.git

catch SIGHUP so that sleeps can be interrupted by the user

A SIGHUP sent to the dma process will run the no-op signal handler and
break the sleep(3) call in deliver.
Do not increase the backoff if sleep was interrupted.

Submitted-by:  Peter Pentchev <roam@ringlet.net> (earlier version)
---

diff --git a/dma.c b/dma.c
index 61cae68..7012bba 100644
--- a/dma.c
+++ b/dma.c
@@ -82,6 +82,12 @@ struct config config = {
 };
 
 
+static void
+sighup_handler(int signo)
+{
+	(void)signo;	/* so that gcc doesn't complain */
+}
+
 static char *
 set_from(struct queue *queue, const char *osender)
 {
@@ -294,8 +300,8 @@ retry:
 				 MAX_TIMEOUT);
 			goto bounce;
 		}
-		sleep(backoff);
-		backoff *= 2;
+		if (sleep(backoff) == 0)
+			backoff *= 2;
 		if (backoff > MAX_RETRY)
 			backoff = MAX_RETRY;
 		goto retry;
@@ -358,6 +364,7 @@ show_queue(struct queue *queue)
 int
 main(int argc, char **argv)
 {
+	struct sigaction act;
 	char *sender = NULL;
 	struct queue queue;
 	int i, ch;
@@ -472,6 +479,12 @@ skipopts:
 
 	/* XXX fork root here */
 
+	act.sa_handler = sighup_handler;
+	act.sa_flags = 0;
+	sigemptyset(&act.sa_mask);
+	if (sigaction(SIGHUP, &act, NULL) != 0)
+		syslog(LOG_WARNING, "can not set signal handler: %m");
+
 	parse_conf(CONF_PATH);
 
 	if (config.authpath != NULL)