[PATCH v2 2/2] iproute/iprule: restore support for kernel versions missing RTA_TABLE routing attribute

[Eugene Rudoy]

iproute/iprule applets fail to compile when compiled using kernel versions < 2.6.19

 iproute.c: In function 'print_route':
 iproute.c:85:9: error: 'RTA_TABLE' undeclared (first use in this function)
 iproute.c:85:9: note: each undeclared identifier is reported only once for each function it appears in
 iproute.c: In function 'iproute_modify':
 iproute.c:467:36: error: 'RTA_TABLE' undeclared (first use in this function)

Fix it by partially #ifdef'ing the code added in b42107f21538e39d9a344376372f8261aed589b2

Signed-off-by: Eugene Rudoy <gene.devel at gmail.com>
---

 v2: change the order of if/else-branches to reduce the number of #ifdef's
     as suggested by Walter Harms
---
 networking/libiproute/iproute.c | 14 ++++++++++----
 networking/libiproute/iprule.c  | 19 ++++++++++++++-----
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/networking/libiproute/iproute.c b/networking/libiproute/iproute.c
index e8b26cb2f..9b3d9c3b8 100644
--- a/networking/libiproute/iproute.c
+++ b/networking/libiproute/iproute.c
@@ -14,6 +14,9 @@
 #include "rt_names.h"
 #include "utils.h"
 
+#include <linux/version.h>
+#define HAVE_RTA_TABLE (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,19))
+
 #ifndef RTAX_RTTVAR
 #define RTAX_RTTVAR RTAX_HOPS
 #endif
@@ -81,9 +84,11 @@ static int FAST_FUNC print_route(const struct sockaddr_nl *who UNUSED_PARAM,
 	memset(tb, 0, sizeof(tb));
 	parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
 
+#if HAVE_RTA_TABLE
 	if (tb[RTA_TABLE])
 		tid = *(uint32_t *)RTA_DATA(tb[RTA_TABLE]);
 	else
+#endif
 		tid = r->rtm_table;
 
 	if (r->rtm_family == AF_INET6)
@@ -459,12 +464,13 @@ IF_FEATURE_IP_RULE(ARG_table,)
 			NEXT_ARG();
 			if (rtnl_rttable_a2n(&tid, *argv))
 				invarg_1_to_2(*argv, keyword_table);
-			if (tid < 256)
-				req.r.rtm_table = tid;
-			else {
+#if HAVE_RTA_TABLE
+			if (tid > 255) {
 				req.r.rtm_table = RT_TABLE_UNSPEC;
 				addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
-			}
+			} else
+#endif
+				req.r.rtm_table = tid;
 #endif
 		} else if (arg == ARG_dev || arg == ARG_oif) {
 			NEXT_ARG();
diff --git a/networking/libiproute/iprule.c b/networking/libiproute/iprule.c
index 9938b4793..772890982 100644
--- a/networking/libiproute/iprule.c
+++ b/networking/libiproute/iprule.c
@@ -24,6 +24,9 @@
 #include "rt_names.h"
 #include "utils.h"
 
+#include <linux/version.h>
+#define HAVE_RTA_TABLE (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,19))
+
 /* If you add stuff here, update iprule_full_usage */
 static const char keywords[] ALIGN1 =
 	"from\0""to\0""preference\0""order\0""priority\0"
@@ -120,9 +123,12 @@ static int FAST_FUNC print_rule(const struct sockaddr_nl *who UNUSED_PARAM,
 		printf("iif %s ", (char*)RTA_DATA(tb[RTA_IIF]));
 	}
 
+#if HAVE_RTA_TABLE
 	if (tb[RTA_TABLE])
 		printf("lookup %s ", rtnl_rttable_n2a(*(uint32_t*)RTA_DATA(tb[RTA_TABLE])));
-	else if (r->rtm_table)
+	else
+#endif
+	if (r->rtm_table)
 		printf("lookup %s ", rtnl_rttable_n2a(r->rtm_table));
 
 	if (tb[FRA_SUPPRESS_PREFIXLEN]) {
@@ -266,12 +272,15 @@ static int iprule_modify(int cmd, char **argv)
 			NEXT_ARG();
 			if (rtnl_rttable_a2n(&tid, *argv))
 				invarg_1_to_2(*argv, "table ID");
-			if (tid < 256)
-				req.r.rtm_table = tid;
-			else {
+
+#if HAVE_RTA_TABLE
+			if (tid > 255) {
 				req.r.rtm_table = RT_TABLE_UNSPEC;
 				addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
-			}
+			} else
+#endif
+				req.r.rtm_table = tid;
+
 			table_ok = 1;
 		} else if (key == ARG_suppress_prefixlength) {
 			int prefix_length;
-- 
2.14.2