arp: Convert to iov_tail

Use packet_data() and extract headers using IOV_REMOVE_HEADER()
rather than packet_get().

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

2 files changed, 9 insertions, 4 deletions

diff --git a/arp.c b/arp.c
index 9f1fede..b3ac420 100644
--- a/arp.c
+++ b/arp.c
@@ -74,14 +74,20 @@ int arp(const struct ctx *c, const struct pool *p)
 		struct arphdr ah;
 		struct arpmsg am;
 	} __attribute__((__packed__)) resp;
+	struct arphdr ah_storage;
+	struct ethhdr eh_storage;
+	struct arpmsg am_storage;
 	const struct ethhdr *eh;
 	const struct arphdr *ah;
 	const struct arpmsg *am;
+	struct iov_tail data;
 
-	eh = packet_get(p, 0, 0,			 sizeof(*eh), NULL);
-	ah = packet_get(p, 0, sizeof(*eh),		 sizeof(*ah), NULL);
-	am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
+	if (!packet_data(p, 0, &data))
+		return -1;
 
+	eh = IOV_REMOVE_HEADER(&data, eh_storage);
+	ah = IOV_REMOVE_HEADER(&data, ah_storage);
+	am = IOV_REMOVE_HEADER(&data, am_storage);
 	if (!eh || !ah || !am)
 		return -1;
 
diff --git a/packet.c b/packet.c
index 82adc9f..34b1722 100644
--- a/packet.c
+++ b/packet.c
@@ -201,7 +201,6 @@ void *packet_get_do(const struct pool *p, const size_t idx,
  * Return: false if packet index is invalid, true otherwise.
  * 	   If something wrong with @data, don't return at all (assert).
  */
-/* cppcheck-suppress unusedFunction */
 bool packet_data_do(const struct pool *p, size_t idx,
 		    struct iov_tail *data,
 		    const char *func, int line)