Fix obtaining netmask on NetBSD.

diff --git a/net.c b/net.c
index 4502a3a5629c4af18caa910886484236649c9c7d..1d8e1055fe500b461a372b505df85bb815e8cbd3 100644 (file)
--- a/net.c
+++ b/net.c
@@ -285,6 +285,7 @@ do_interface(const char *ifname,
        char *p, *e;
        in_addr_t address, netmask;
        struct ifreq *ifr;
+       struct sockaddr_in *sin;
 
        if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
                return -1;
@@ -312,7 +313,7 @@ do_interface(const char *ifname,
                len *= 2;
        }
 
-       e = ifc.ifc_buf + ifc.ifc_len;
+       e = (char *)ifc.ifc_buf + ifc.ifc_len;
        for (p = ifc.ifc_buf; p < e;) {
                ifr = (struct ifreq *)p;
 
@@ -336,12 +337,14 @@ do_interface(const char *ifname,
                }
 
                if (ifr->ifr_addr.sa_family == AF_INET && addr) {
-                       address = ((struct sockaddr_in *)&ifr->ifr_addr)
-                                 ->sin_addr.s_addr;
+                       sin = (struct sockaddr_in *)&ifr->ifr_addr;
+                       address = sin->sin_addr.s_addr;
+                       /* Some platforms only partially fill the bits
+                        * set by the netmask, so we need to zero it now. */
+                       sin->sin_addr.s_addr = 0;
                        if (ioctl(s, SIOCGIFNETMASK, ifr) == -1)
                                continue;
-                       netmask = ((struct sockaddr_in *)&ifr->ifr_addr)
-                                 ->sin_addr.s_addr;
+                       netmask = sin->sin_addr.s_addr;
                        if (act == 1) {
                                addr->s_addr = address;
                                net->s_addr = netmask;