///////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  File:   RoutingContract.gs
//  Note:   Contract definition for interacting with the IP Routing module
//

using Microsoft.Singularity.Channels;
using Microsoft.Singularity.Directory;

namespace NetStack.Contracts
{
    public rep struct Network
    {
        public uint network;
        public uint netmask;
    }

    public rep struct RouteEntry
    {
        public Network network;
        public uint gateway;
        public uint ifaddr;
        public uint metric;
        public uint tag;
    }

    public contract RoutingContract : ServiceContract
    {
        // This is the name under which the routing module
        // registers itself with the name server.
        public const string ModuleName = "/dev/routing";

        // Response messages
        out message RoutingTable(RouteEntry[] in ExHeap routes);
        out message Err();
        out message NoRouteFound();
        out message Route(RouteEntry route);
        out message OK();

        // Request messages
        in message GetRoutingTable();
        in message AddRoute(Network dest, uint gateway, uint ifaddr);

        in message DeleteRoute(Network dest);

        // Find routes towards the indicated destination or network
        in message FindHostRoute(uint dest);
        in message FindNetRoute(Network dest);

        // Find a route specific to this target host
        in message FindSpecificHostRoute(uint dest);

        // Find a route to this exact network
        in message FindSpecificNetRoute(Network dest);

        out message Ready();
        override state Start : Ready! -> ReadyState;

        state ReadyState : one
        {
            GetRoutingTable? -> RoutingTable! -> ReadyState;
            AddRoute? -> (Err! or OK!) -> ReadyState;
            DeleteRoute? -> (NoRouteFound! or OK!) -> ReadyState;

            FindHostRoute? -> (Route! or NoRouteFound!) -> ReadyState;
            FindNetRoute? -> (Route! or NoRouteFound!) -> ReadyState;
            FindSpecificHostRoute? -> (Route! or NoRouteFound!) -> ReadyState;
            FindSpecificNetRoute? -> (Route! or NoRouteFound!) -> ReadyState;
        }
    }
}