From: Sam Tannous <stannous@cumulusnetworks.com>
Date: Tue, 8 Jul 2014 19:15:44 +0000 (-0400)
Subject: make agentx socket non-blocking
X-Git-Tag: 0.7.10~26
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b93e39a167360898368640eb2a113ce7b5cea9f4;p=thirdparty%2Flldpd.git

make agentx socket non-blocking

This patch makes the lldpd socket non-blocking. And also adds a brief
retry.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Sam Tannous <stannous@cumulusnetworks.com>
---

diff --git a/src/daemon/agent_priv.c b/src/daemon/agent_priv.c
index 10929e47..88e8e958 100644
--- a/src/daemon/agent_priv.c
+++ b/src/daemon/agent_priv.c
@@ -80,12 +80,27 @@ static int
 agent_priv_unix_send(netsnmp_transport *t, void *buf, int size,
     void **opaque, int *olength)
 {
-	int rc = -1;
+	int rc = -1, retry = 4;
+	useconds_t usecs = 250000;
+
 	if (t != NULL && t->sock >= 0) {
 		while (rc < 0) {
 			rc = send(t->sock, buf, size, 0);
-			if (rc < 0 && errno != EINTR) {
-				break;
+			if (rc < 0) {
+				if (errno == EAGAIN || errno == EWOULDBLOCK) {
+					if (--retry <= 0)
+						break;
+
+					log_info("snmp", "%s: retrying after "
+						"%d secs...\n", __FUNCTION__,
+						usecs);
+					usleep(usecs);
+					continue;
+				} else if (errno != EINTR) {
+					log_info("snmp", "%s: failed with %s\n",
+						__FUNCTION__, strerror(errno));
+					break;
+				}
 			}
 		}
 	}
diff --git a/src/daemon/priv.c b/src/daemon/priv.c
index b6341e44..187d90d9 100644
--- a/src/daemon/priv.c
+++ b/src/daemon/priv.c
@@ -354,6 +354,17 @@ asroot_snmp_socket()
 		must_write(PRIV_PRIVILEGED, &rc, sizeof(int));
 		return;
         }
+
+	if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) {
+		log_warn("privsep", "cannot set sock %s to non-block : %s",
+                          addr->sun_path, strerror(errno));
+
+		close(sock);
+		rc = -1;
+		must_write(PRIV_PRIVILEGED, &rc, sizeof(int));
+		return;
+	}
+
 	must_write(PRIV_PRIVILEGED, &rc, sizeof(int));
 	send_fd(PRIV_PRIVILEGED, sock);
 	close(sock);