From 31cf41f50dddca5d06f07450647de1debab44eb5 Mon Sep 17 00:00:00 2001 From: Sedat Dilek Date: Sun, 28 Jul 2013 12:34:39 +0200 Subject: [PATCH] netlink.c: Fix build failure when NETLINK_NO_ENOBUFS is not defined My build with radvd-1.9.3 and the Freetz build-system breaks with a Linux-kernel v2.6.13.1 like this: netlink.c: In function 'netlink_socket': netlink.c:84:41: error: 'NETLINK_NO_ENOBUFS' undeclared (first use in this function) netlink.c:84:41: note: each undeclared identifier is reported only once for each function it appears in make[2]: *** [netlink.o] Error 1 This is obvious as my kernel-sources have no "NETLINK_NO_ENOBUFS" definition in "include/linux/netlink.h". The culprit is the else-if line here: [ netlink.c ] int netlink_socket(void) { ... if (sock == -1) { flog(LOG_ERR, "Unable to open netlink socket: %s", strerror(errno)); } else if (setsockopt(sock, SOL_NETLINK, NETLINK_NO_ENOBUFS, &val, sizeof(val)) < 0 ) { flog(LOG_ERR, "Unable to setsockopt NETLINK_NO_ENOBUFS: %s", strerror(errno)); } ... The NETLINK_NO_ENOBUFS socket flag was first introduced with Linux-kernel v2.6.29-rc7: commit 38938bfe3489394e2eed5e40c9bb8f66a2ce1405 "netlink: add NETLINK_NO_ENOBUFS socket flag" The issue in radvd was introduced with: commit de9a8849258b2a6a125d686dcb9c424affad354d "setsockopt NETLINK_NO_ENOBUFS" I have added extra checks for SOL_NETLINK and NETLINK_NO_ENOBUFS definitions which fixes the issue for me. NOTE: Compile-tested only! Signed-off-by: Sedat Dilek --- netlink.c | 2 ++ 1 file changed, 2 insertions(+) diff --git netlink.c netlink.c index a37ccad..d405731 100644 --- netlink.c +++ netlink.c @@ -81,9 +81,11 @@ int netlink_socket(void) if (sock == -1) { flog(LOG_ERR, "Unable to open netlink socket: %s", strerror(errno)); } +#if defined SOL_NETLINK && defined NETLINK_NO_ENOBUFS else if (setsockopt(sock, SOL_NETLINK, NETLINK_NO_ENOBUFS, &val, sizeof(val)) < 0 ) { flog(LOG_ERR, "Unable to setsockopt NETLINK_NO_ENOBUFS: %s", strerror(errno)); } +#endif memset(&snl, 0, sizeof(snl)); snl.nl_family = AF_NETLINK; -- 1.8.3.4