Check if SO_REUSEPORT is defined before using it.

[meshlink] / src / discovery.c

diff --git a/src/discovery.c b/src/discovery.c
index 65c197409808acbc65469f6139dc164b4fdba735..5cc1d4121b426a7d38de104769244991028a7b7f 100644 (file)
--- a/src/discovery.c
+++ b/src/discovery.c
@@ -1,3 +1,22 @@
+/*
+  discovery.c -- local network discovery
+  Copyright (C) 2014-2021 Guus Sliepen <guus@meshlink.io>
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along
+  with this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
 #define __APPLE_USE_RFC_3542
 #include "system.h"
 
@@ -413,8 +432,8 @@ static void addr_del(meshlink_handle_t *mesh, const discovery_address_t *addr) {
        memmove(p, p + 1, (mesh->discovery.addresses + --mesh->discovery.address_count - p) * sizeof(*p));
 }
 
-#if !defined(__linux) && (defined(RTM_NEWADDR) || defined(__APPLE__))
-static void scan_ifaddrs(meshlink_handle_t *mesh) {
+void scan_ifaddrs(meshlink_handle_t *mesh) {
+#ifdef HAVE_GETIFADDRS
        struct ifaddrs *ifa = NULL;
 
        if(getifaddrs(&ifa) == -1) {
@@ -512,8 +531,10 @@ static void scan_ifaddrs(meshlink_handle_t *mesh) {
        }
 
        freeifaddrs(ifa);
-}
+#else
+       (void)mesh;
 #endif
+}
 
 #if defined(__linux)
 static void netlink_getlink(int fd) {
@@ -885,7 +906,9 @@ bool discovery_start(meshlink_handle_t *mesh) {
                .in.sin_port = ntohs(5353),
        };
        setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+#ifdef SO_REUSEPORT
        setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
+#endif
        setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one8, sizeof(one8));
        setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl8, sizeof(ttl8));
 
@@ -906,7 +929,9 @@ bool discovery_start(meshlink_handle_t *mesh) {
        }
 
        setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+#ifdef SO_REUSEPORT
        setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
+#endif
        setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
        setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
        setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl));
@@ -932,9 +957,11 @@ bool discovery_start(meshlink_handle_t *mesh) {
                        netlink_getlink(sock);
                } else {
                        logger(mesh, MESHLINK_WARNING, "Could not bind AF_NETLINK socket: %s", strerror(errno));
+                       scan_ifaddrs(mesh);
                }
        } else {
                logger(mesh, MESHLINK_WARNING, "Could not open AF_NETLINK socket: %s", strerror(errno));
+               scan_ifaddrs(mesh);
        }
 
 #elif defined(__APPLE__)