chromium/third_party/grpc/src/include/grpcpp/completion_queue.h

//
//
// Copyright 2015 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.
//
//

/// A completion queue implements a concurrent producer-consumer queue, with
/// two main API-exposed methods: \a Next and \a AsyncNext. These
/// methods are the essential component of the gRPC C++ asynchronous API.
/// There is also a \a Shutdown method to indicate that a given completion queue
/// will no longer have regular events. This must be called before the
/// completion queue is destroyed.
/// All completion queue APIs are thread-safe and may be used concurrently with
/// any other completion queue API invocation; it is acceptable to have
/// multiple threads calling \a Next or \a AsyncNext on the same or different
/// completion queues, or to call these methods concurrently with a \a Shutdown
/// elsewhere.
/// \remark{All other API calls on completion queue should be completed before
/// a completion queue destructor is called.}
#ifndef GRPCPP_COMPLETION_QUEUE_H
#define GRPCPP_COMPLETION_QUEUE_H

#include <list>

#include <grpc/grpc.h>
#include <grpc/support/atm.h>
#include <grpc/support/log.h>
#include <grpc/support/time.h>
#include <grpcpp/impl/codegen/rpc_service_method.h>
#include <grpcpp/impl/codegen/status.h>
#include <grpcpp/impl/codegen/sync.h>
#include <grpcpp/impl/codegen/time.h>
#include <grpcpp/impl/completion_queue_tag.h>
#include <grpcpp/impl/grpc_library.h>
#include <grpcpp/impl/sync.h>

struct grpc_completion_queue;

namespace grpc {
template <class R>
class ClientReader;
template <class W>
class ClientWriter;
template <class W, class R>
class ClientReaderWriter;
template <class R>
class ServerReader;
template <class W>
class ServerWriter;
namespace internal {
template <class W, class R>
class ServerReaderWriterBody;

template <class ResponseType>
void UnaryRunHandlerHelper(
    const grpc::internal::MethodHandler::HandlerParameter&, ResponseType*,
    grpc::Status&);
template <class ServiceType, class RequestType, class ResponseType,
          class BaseRequestType, class BaseResponseType>
class RpcMethodHandler;
template <class ServiceType, class RequestType, class ResponseType>
class ClientStreamingHandler;
template <class ServiceType, class RequestType, class ResponseType>
class ServerStreamingHandler;
template <class Streamer, bool WriteNeeded>
class TemplatedBidiStreamingHandler;
template <grpc::StatusCode code>
class ErrorMethodHandler;
}  // namespace internal

class Channel;
class ChannelInterface;
class Server;
class ServerBuilder;
class ServerContextBase;
class ServerInterface;

namespace internal {
class CompletionQueueTag;
class RpcMethod;
template <class InputMessage, class OutputMessage>
class BlockingUnaryCallImpl;
template <class Op1, class Op2, class Op3, class Op4, class Op5, class Op6>
class CallOpSet;
}  // namespace internal

/// A thin wrapper around \ref grpc_completion_queue (see \ref
/// src/core/lib/surface/completion_queue.h).
/// See \ref doc/cpp/perf_notes.md for notes on best practices for high
/// performance servers.
class CompletionQueue : private grpc::internal::GrpcLibrary { … };

/// A specific type of completion queue used by the processing of notifications
/// by servers. Instantiated by \a ServerBuilder or Server (for health checker).
class ServerCompletionQueue : public CompletionQueue { … };

}  // namespace grpc

#endif  // GRPCPP_COMPLETION_QUEUE_H