[PATCH v2] ipvsadm: fix compiling tool on distros with only libnl-1

[Jesper Dangaard Brouer <brouer@redhat.com>]

Some distros have not moved to libnl3 yet.  Add a fallback option
for compiling on distro's with only libnl1.

Using pkg-config to detect what versions of libnl is available.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
---
V2: My git mail config were wrongly configured, and the orig
    patch only reached RedHat recipients, thus I'm resending
    hoping my email client does not screw the patches...

 libipvs/Makefile  |    5 +++++
 libipvs/libipvs.c |    5 +++++
 2 files changed, 10 insertions(+)

diff --git a/libipvs/Makefile b/libipvs/Makefile
index a527a7f..eafc3e5 100644
--- a/libipvs/Makefile
+++ b/libipvs/Makefile
@@ -10,6 +10,11 @@ INCLUDE		+= $(shell if [ -f ../../ip_vs.h ]; then	\
 		     echo "-I../../."; fi;)
 DEFINES		= $(shell if [ ! -f ../../ip_vs.h ]; then	\
 		    echo "-DHAVE_NET_IP_VS_H"; fi;)
+DEFINES		+= $(shell if which pkg-config > /dev/null 2>&1; then \
+			 if   pkg-config --exists libnl-3.0; then :; \
+			 elif pkg-config --exists libnl-2.0; then :; \
+			 elif pkg-config --exists libnl-1; \
+			 then echo "-DFALLBACK_LIBNL1"; fi; fi)
 
 .PHONY		= all clean install dist distclean rpm rpms
 STATIC_LIB	= libipvs.a
diff --git a/libipvs/libipvs.c b/libipvs/libipvs.c
index c3c3b0a..2b066d2 100644
--- a/libipvs/libipvs.c
+++ b/libipvs/libipvs.c
@@ -32,6 +32,11 @@ static void* ipvs_func = NULL;
 struct ip_vs_getinfo ipvs_info;
 
 #ifdef LIBIPVS_USE_NL
+#ifdef FALLBACK_LIBNL1
+#define nl_sock         nl_handle
+#define nl_socket_alloc nl_handle_alloc
+#define nl_socket_free  nl_handle_destroy
+#endif
 static struct nl_sock *sock = NULL;
 static int family, try_nl = 1;
 #endif