// Copyright (c) 2013-2014 Sandstorm Development Group, Inc. and contributors // Licensed under the MIT License: // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. #ifndef CAPNP_RPC_TWOPARTY_H_ #define CAPNP_RPC_TWOPARTY_H_ #if defined(__GNUC__) && !CAPNP_HEADER_WARNINGS #pragma GCC system_header #endif #include "rpc.h" #include "message.h" #include <kj/async-io.h> #include <capnp/rpc-twoparty.capnp.h> namespace capnp { namespace rpc { namespace twoparty { typedef VatId SturdyRefHostId; // For backwards-compatibility with version 0.4. } } typedef VatNetwork<rpc::twoparty::VatId, rpc::twoparty::ProvisionId, rpc::twoparty::RecipientId, rpc::twoparty::ThirdPartyCapId, rpc::twoparty::JoinResult> TwoPartyVatNetworkBase; class TwoPartyVatNetwork: public TwoPartyVatNetworkBase, private TwoPartyVatNetworkBase::Connection { // A `VatNetwork` that consists of exactly two parties communicating over an arbitrary byte // stream. This is used to implement the common case of a client/server network. // // See `ez-rpc.h` for a simple interface for setting up two-party clients and servers. // Use `TwoPartyVatNetwork` only if you need the advanced features. public: TwoPartyVatNetwork(kj::AsyncIoStream& stream, rpc::twoparty::Side side, ReaderOptions receiveOptions = ReaderOptions()); KJ_DISALLOW_COPY(TwoPartyVatNetwork); kj::Promise<void> onDisconnect() { return disconnectPromise.addBranch(); } // Returns a promise that resolves when the peer disconnects. rpc::twoparty::Side getSide() { return side; } // implements VatNetwork ----------------------------------------------------- kj::Maybe<kj::Own<TwoPartyVatNetworkBase::Connection>> connect( rpc::twoparty::VatId::Reader ref) override; kj::Promise<kj::Own<TwoPartyVatNetworkBase::Connection>> accept() override; private: class OutgoingMessageImpl; class IncomingMessageImpl; kj::AsyncIoStream& stream; rpc::twoparty::Side side; MallocMessageBuilder peerVatId; ReaderOptions receiveOptions; bool accepted = false; kj::Maybe<kj::Promise<void>> previousWrite; // Resolves when the previous write completes. This effectively serves as the write queue. // Becomes null when shutdown() is called. kj::Own<kj::PromiseFulfiller<kj::Own<TwoPartyVatNetworkBase::Connection>>> acceptFulfiller; // Fulfiller for the promise returned by acceptConnectionAsRefHost() on the client side, or the // second call on the server side. Never fulfilled, because there is only one connection. kj::ForkedPromise<void> disconnectPromise = nullptr; class FulfillerDisposer: public kj::Disposer { // Hack: TwoPartyVatNetwork is both a VatNetwork and a VatNetwork::Connection. Whet the RPC // system detects (or initiates) a disconnection, it drops its reference to the Connection. // When all references have been dropped, then we want onDrained() to fire. So we hand out // Own<Connection>s with this disposer attached, so that we can detect when they are dropped. public: mutable kj::Own<kj::PromiseFulfiller<void>> fulfiller; mutable uint refcount = 0; void disposeImpl(void* pointer) const override; }; FulfillerDisposer disconnectFulfiller; kj::Own<TwoPartyVatNetworkBase::Connection> asConnection(); // Returns a pointer to this with the disposer set to drainedFulfiller. // implements Connection ----------------------------------------------------- rpc::twoparty::VatId::Reader getPeerVatId() override; kj::Own<OutgoingRpcMessage> newOutgoingMessage(uint firstSegmentWordSize) override; kj::Promise<kj::Maybe<kj::Own<IncomingRpcMessage>>> receiveIncomingMessage() override; kj::Promise<void> shutdown() override; }; class TwoPartyServer: private kj::TaskSet::ErrorHandler { // Convenience class which implements a simple server which accepts connections on a listener // socket and serices them as two-party connections. public: explicit TwoPartyServer(Capability::Client bootstrapInterface); kj::Promise<void> listen(kj::ConnectionReceiver& listener); // Listens for connections on the given listener. The returned promise never resolves unless an // exception is thrown while trying to accept. You may discard the returned promise to cancel // listening. private: Capability::Client bootstrapInterface; kj::TaskSet tasks; struct AcceptedConnection; void taskFailed(kj::Exception&& exception) override; }; class TwoPartyClient { // Convenience class which implements a simple client. public: explicit TwoPartyClient(kj::AsyncIoStream& connection); TwoPartyClient(kj::AsyncIoStream& connection, Capability::Client bootstrapInterface, rpc::twoparty::Side side = rpc::twoparty::Side::CLIENT); Capability::Client bootstrap(); // Get the server's bootstrap interface. inline kj::Promise<void> onDisconnect() { return network.onDisconnect(); } private: TwoPartyVatNetwork network; RpcSystem<rpc::twoparty::VatId> rpcSystem; }; } // namespace capnp #endif // CAPNP_RPC_TWOPARTY_H_