commit bcbe92fb080420551125994f3b15c139019da694
author Sebastian Ottlik <ottlik@fzi.de> Wed Oct 02 12:23:14 2013 +0200
committer Stefan Weil <sw@weilnetz.de> Wed Oct 02 19:20:31 2013 +0200
tree 6d9c945c3cdaf9613465799ce68ecd97ee41ca95
parent 6669ca13c39a8515cc634695698d3dea5f39be1c

net: call socket_set_fast_reuse instead of setting SO_REUSEADDR

SO_REUSEADDR should be avoided on Windows but is desired on other operating
systems. So instead of setting it we call socket_set_fast_reuse that will result
in the appropriate behaviour on all operating systems.

An exception to this rule are multicast sockets where it is sensible to have
multiple sockets listen on the same ip and port and we should set SO_REUSEADDR
on windows.

Signed-off-by: Sebastian Ottlik <ottlik@fzi.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>

net/socket.c

diff --git a/net/socket.c b/net/socket.c
index e61309d..fb21e20 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -262,6 +262,11 @@
         return -1;
     }
 
+    /* Allow multiple sockets to bind the same multicast ip and port by setting
+     * SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
+     * on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
+     * only on posix systems.
+     */
     val = 1;
     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
     if (ret < 0) {
@@ -510,7 +515,7 @@
     NetClientState *nc;
     NetSocketState *s;
     struct sockaddr_in saddr;
-    int fd, val, ret;
+    int fd, ret;
 
     if (parse_host_port(&saddr, host_str) < 0)
         return -1;
@@ -522,9 +527,7 @@
     }
     qemu_set_nonblock(fd);
 
-    /* allow fast reuse */
-    val = 1;
-    qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
+    socket_set_fast_reuse(fd);
 
     ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
     if (ret < 0) {
@@ -645,7 +648,7 @@
                                  const char *lhost)
 {
     NetSocketState *s;
-    int fd, val, ret;
+    int fd, ret;
     struct sockaddr_in laddr, raddr;
 
     if (parse_host_port(&laddr, lhost) < 0) {
@@ -661,11 +664,9 @@
         perror("socket(PF_INET, SOCK_DGRAM)");
         return -1;
     }
-    val = 1;
-    ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
-                          &val, sizeof(val));
+
+    ret = socket_set_fast_reuse(fd);
     if (ret < 0) {
-        perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
         closesocket(fd);
         return -1;
     }