net: add a client type code

This is so as to allow APIs which operate on specific client types
without having to add a function table entry which is only implemented
by a single client type.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/net.h b/net.h
index c96f291..f592ffb 100644
--- a/net.h
+++ b/net.h
@@ -26,6 +26,16 @@
 
 /* VLANs support */
 
+typedef enum {
+    NET_CLIENT_TYPE_NONE,
+    NET_CLIENT_TYPE_NIC,
+    NET_CLIENT_TYPE_SLIRP,
+    NET_CLIENT_TYPE_TAP,
+    NET_CLIENT_TYPE_SOCKET,
+    NET_CLIENT_TYPE_VDE,
+    NET_CLIENT_TYPE_DUMP
+} net_client_type;
+
 typedef int (NetCanReceive)(VLANClientState *);
 typedef ssize_t (NetReceive)(VLANClientState *, const uint8_t *, size_t);
 typedef ssize_t (NetReceiveIOV)(VLANClientState *, const struct iovec *, int);
@@ -33,6 +43,7 @@
 typedef void (LinkStatusChanged)(VLANClientState *);
 
 struct VLANClientState {
+    net_client_type type;
     NetReceive *receive;
     NetReceiveIOV *receive_iov;
     /* Packets may still be sent if this returns zero.  It's used to