| /* |
| * |
| * Copyright 2016 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H |
| #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include <ares.h> |
| #include "src/core/lib/iomgr/pollset_set.h" |
| #include "src/core/lib/iomgr/work_serializer.h" |
| |
| namespace grpc_core { |
| |
| /* A wrapped fd that integrates with the grpc iomgr of the current platform. |
| * A GrpcPolledFd knows how to create grpc platform-specific iomgr endpoints |
| * from "ares_socket_t" sockets, and then sign up for readability/writeability |
| * with that poller, and do shutdown and destruction. */ |
| class GrpcPolledFd { |
| public: |
| virtual ~GrpcPolledFd() {} |
| /* Called when c-ares library is interested and there's no pending callback */ |
| virtual void RegisterForOnReadableLocked(grpc_closure* read_closure) = 0; |
| /* Called when c-ares library is interested and there's no pending callback */ |
| virtual void RegisterForOnWriteableLocked(grpc_closure* write_closure) = 0; |
| /* Indicates if there is data left even after just being read from */ |
| virtual bool IsFdStillReadableLocked() = 0; |
| /* Called once and only once. Must cause cancellation of any pending |
| * read/write callbacks. */ |
| virtual void ShutdownLocked(grpc_error_handle error) = 0; |
| /* Get the underlying ares_socket_t that this was created from */ |
| virtual ares_socket_t GetWrappedAresSocketLocked() = 0; |
| /* A unique name, for logging */ |
| virtual const char* GetName() = 0; |
| }; |
| |
| /* A GrpcPolledFdFactory is 1-to-1 with and owned by the |
| * ares event driver. It knows how to create GrpcPolledFd's |
| * for the current platform, and the ares driver uses it for all of |
| * its fd's. */ |
| class GrpcPolledFdFactory { |
| public: |
| virtual ~GrpcPolledFdFactory() {} |
| /* Creates a new wrapped fd for the current platform */ |
| virtual GrpcPolledFd* NewGrpcPolledFdLocked( |
| ares_socket_t as, grpc_pollset_set* driver_pollset_set, |
| std::shared_ptr<grpc_core::WorkSerializer> work_serializer) = 0; |
| /* Optionally configures the ares channel after creation */ |
| virtual void ConfigureAresChannelLocked(ares_channel channel) = 0; |
| }; |
| |
| std::unique_ptr<GrpcPolledFdFactory> NewGrpcPolledFdFactory( |
| std::shared_ptr<grpc_core::WorkSerializer> work_serializer); |
| |
| } // namespace grpc_core |
| |
| #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H \ |
| */ |