Add alloca_packet() macro

2 files changed, 10 insertions, 6 deletions

diff --git a/src/packet.h b/src/packet.h
index 286192e..07c0f3b 100644
--- a/src/packet.h
+++ b/src/packet.h
@@ -29,6 +29,8 @@
 
 #include "types.h"
 
+#include <alloca.h>
+
 #include <arpa/inet.h>
 
 
@@ -41,6 +43,13 @@ struct __attribute__((packed)) gp_babel_packet {
 	uint8_t tlv[];
 };
 
+#define alloca_packet(size) ({ \
+			gp_babel_packet_t *__packet = alloca(sizeof(gp_babel_packet_t)+size); \
+			__packet->version = htons(GP_BABEL_VERSION);	\
+			__packet->len = 0;				\
+			__packet;					\
+		})
+
 static inline size_t gp_babel_packet_size(const gp_babel_packet_t *packet) {
 	return sizeof(gp_babel_packet_t)+ntohs(packet->len);
 }
diff --git a/src/send.c b/src/send.c
index 5f06218..7fc9453 100644
--- a/src/send.c
+++ b/src/send.c
@@ -30,8 +30,6 @@
 #include "tlv.h"
 #include "tlv_types.h"
 
-#include <alloca.h>
-
 
 static void add_ihus(gmrf_t *gmrf, gp_babel_packet_t *packet, size_t max_len, const gp_babel_iface_t *iface) {
 	const gp_babel_neigh_t *neigh;
@@ -52,10 +50,7 @@ static void add_ihus(gmrf_t *gmrf, gp_babel_packet_t *packet, size_t max_len, co
 void gp_babel_send_hellos(gmrf_t *gmrf, gmrf_context_t *ctx) {
 	gmrf_logf(gmrf, LOG_DEBUG, "sending hellos...");
 
-	gp_babel_packet_t *packet = alloca(sizeof(gp_babel_packet_t)+GP_BABEL_PACKET_MAX);
-
-	packet->version = htons(GP_BABEL_VERSION);
-	packet->len = 0;
+	gp_babel_packet_t *packet = alloca_packet(GP_BABEL_PACKET_MAX);
 
 	gp_babel_tlv_hello_t *hello = gp_babel_tlv_add(packet, GP_BABEL_PACKET_MAX, TLV_HELLO, sizeof(gp_babel_tlv_hello_t));
 	if (!hello)