net/queue: introduce NetQueueDeliverFunc

net/queue.c has logic to send/queue/flush packets but a
qemu_deliver_packet_iov() call is hardcoded. Abstract this
func so that we can use our own deliver function in netfilter.

Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
diff --git a/net/queue.c b/net/queue.c
index cf8db3a..16dddf0 100644
--- a/net/queue.c
+++ b/net/queue.c
@@ -52,13 +52,14 @@
     void *opaque;
     uint32_t nq_maxlen;
     uint32_t nq_count;
+    NetQueueDeliverFunc *deliver;
 
     QTAILQ_HEAD(packets, NetPacket) packets;
 
     unsigned delivering : 1;
 };
 
-NetQueue *qemu_new_net_queue(void *opaque)
+NetQueue *qemu_new_net_queue(NetQueueDeliverFunc *deliver, void *opaque)
 {
     NetQueue *queue;
 
@@ -67,6 +68,7 @@
     queue->opaque = opaque;
     queue->nq_maxlen = 10000;
     queue->nq_count = 0;
+    queue->deliver = deliver;
 
     QTAILQ_INIT(&queue->packets);
 
@@ -158,7 +160,7 @@
     };
 
     queue->delivering = 1;
-    ret = qemu_deliver_packet_iov(sender, flags, &iov, 1, queue->opaque);
+    ret = queue->deliver(sender, flags, &iov, 1, queue->opaque);
     queue->delivering = 0;
 
     return ret;
@@ -173,7 +175,7 @@
     ssize_t ret = -1;
 
     queue->delivering = 1;
-    ret = qemu_deliver_packet_iov(sender, flags, iov, iovcnt, queue->opaque);
+    ret = queue->deliver(sender, flags, iov, iovcnt, queue->opaque);
     queue->delivering = 0;
 
     return ret;