From: Gerrit Renker <grenker@cscs.ch>
Date: Wed, 3 Mar 2010 16:57:14 +0000 (+0100)
Subject: net: revert restricting SO_REUSEADDR
X-Git-Tag: v0.4.2~30
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=8cf2884a87db0eca0aa2f382c9850335332682b3

net: revert restricting SO_REUSEADDR

This reverts part of commit a5927501e41fa3fca2975452617474e78ffecc48
(08_refactor-makesock.diff, 25 Feb 2010), which restricted by default
SO_REUSEADDR to connection-oriented protocols only - it used to be
set on all passive sockets.

However, the same problem exists also for UDP, whenever connecting
more than one listener on the same host, hence revert it.
---

diff --git a/net.c b/net.c
index aeeca20e..b44d1d3e 100644
--- a/net.c
+++ b/net.c
@@ -384,7 +384,7 @@ int makesock(unsigned l4type, bool passive,
 	struct addrinfo *local = NULL, *src,
 			*remote = NULL, *dst, hints;
 	unsigned int	l3type = AF_UNSPEC;
-	int		rc, sockfd = -1,
+	int		rc, on = 1, sockfd = -1,
 			socktype = sock_type(l4type);
 	char port[6]; /* port number has at most 5 digits */
 
@@ -429,6 +429,18 @@ int makesock(unsigned l4type, bool passive,
 		if (sockfd < 0)
 			goto get_next_dst;
 
+		/*
+		 * Reuse the address on passive sockets to avoid failure on
+		 * restart (protocols using listen()) and when creating
+		 * multiple listener instances (UDP multicast).
+		 */
+		if (passive && setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
+						  &on, sizeof(on)) == -1) {
+			rc = errno;
+			PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n",
+				       strerror(rc));
+			return -ERRNO_TO_PARA_ERROR(rc);
+		}
 		flowopt_setopts(sockfd, fo);
 
 		if (src) {
@@ -480,15 +492,8 @@ get_next_src:
  */
 int para_listen(unsigned l4type, uint16_t port, struct flowopts *fo)
 {
-	int fd, ret;
-
-	if (fo == NULL)
-		fo = flowopt_new();
-
-	/* Reuse the address to avoid failure on restart. */
-	OPT_ENABLE(fo, SOL_SOCKET, SO_REUSEADDR);
+	int ret, fd = makesock(l4type, 1, NULL, port, fo);
 
-	fd = makesock(l4type, 1, NULL, port, fo);
 	if (fd > 0) {
 		ret = listen(fd, BACKLOG);
 		if (ret < 0) {