decode: implement bypass function

Call the packet bypass callback if necessary and update the flow
state. In case of failure we switch to local bypassed state and set
capture bypassed state if the callback is successful.

src/decode.c

@@ -384,8 +384,18 @@ void PacketDefragPktSetupParent(Packet *parent)
 
 void PacketBypassCallback(Packet *p)
 {
-    if (p->BypassPacketsFlow) {
-        p->BypassPacketsFlow(p);
+    /* Don't try to bypass if flow is already out or
+     * if we have failed to do it once */
+    int state = SC_ATOMIC_GET(p->flow->flow_state);
+    if ((state == FLOW_STATE_LOCAL_BYPASSED) ||
+           (state == FLOW_STATE_CAPTURE_BYPASSED)) {
+        return;
+    }
+
+    if (p->BypassPacketsFlow && p->BypassPacketsFlow(p)) {
+        FlowUpdateState(p->flow, FLOW_STATE_CAPTURE_BYPASSED);
+    } else {
+        FlowUpdateState(p->flow, FLOW_STATE_LOCAL_BYPASSED);
     }
 }