1 // 2 // Copyright 2015 gRPC authors. 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #ifndef GRPC_SRC_CORE_CLIENT_CHANNEL_CONNECTOR_H 18 #define GRPC_SRC_CORE_CLIENT_CHANNEL_CONNECTOR_H 19 20 #include <grpc/support/port_platform.h> 21 22 #include "src/core/channelz/channelz.h" 23 #include "src/core/lib/channel/channel_args.h" 24 #include "src/core/lib/iomgr/closure.h" 25 #include "src/core/lib/iomgr/error.h" 26 #include "src/core/lib/iomgr/iomgr_fwd.h" 27 #include "src/core/lib/iomgr/resolved_address.h" 28 #include "src/core/lib/transport/transport.h" 29 #include "src/core/util/orphanable.h" 30 #include "src/core/util/ref_counted_ptr.h" 31 #include "src/core/util/time.h" 32 33 namespace grpc_core { 34 35 // Interface for connection-establishment functionality. 36 // Each transport that supports client channels (e.g., not inproc) must 37 // supply an implementation of this. 38 class SubchannelConnector : public InternallyRefCounted<SubchannelConnector> { 39 public: 40 struct Args { 41 // Address to connect to. 42 grpc_resolved_address* address; 43 // Set of pollsets interested in this connection. 44 grpc_pollset_set* interested_parties; 45 // Deadline for connection. 46 Timestamp deadline; 47 // Channel args to be passed to handshakers and transport. 48 ChannelArgs channel_args; 49 }; 50 51 struct Result { 52 // The connected transport. 53 Transport* transport = nullptr; 54 // Channel args to be passed to filters. 55 ChannelArgs channel_args; 56 // Channelz socket node of the connected transport, if any. 57 RefCountedPtr<channelz::SocketNode> socket_node; 58 ResetResult59 void Reset() { 60 if (transport != nullptr) { 61 transport->Orphan(); 62 transport = nullptr; 63 } 64 channel_args = ChannelArgs(); 65 socket_node.reset(); 66 } 67 }; 68 69 // Attempts to connect. 70 // When complete, populates *result and invokes notify. 71 // Only one connection attempt may be in progress at any one time. 72 virtual void Connect(const Args& args, Result* result, 73 grpc_closure* notify) = 0; 74 75 // Cancels any in-flight connection attempt and shuts down the 76 // connector. 77 virtual void Shutdown(grpc_error_handle error) = 0; 78 Orphan()79 void Orphan() override { 80 Shutdown(GRPC_ERROR_CREATE("Subchannel disconnected")); 81 Unref(); 82 } 83 }; 84 85 } // namespace grpc_core 86 87 #endif // GRPC_SRC_CORE_CLIENT_CHANNEL_CONNECTOR_H 88