grpc/include/grpc++/server.h

/*
 *
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#ifndef GRPCXX_SERVER_H
#define GRPCXX_SERVER_H

#include <condition_variable>
#include <list>
#include <memory>
#include <mutex>

#include <grpc++/completion_queue.h>
#include <grpc++/config.h>
#include <grpc++/impl/call.h>
#include <grpc++/impl/service_type.h>
#include <grpc++/status.h>

struct grpc_server;

namespace grpc {
class AsynchronousService;
class GenericServerContext;
class AsyncGenericService;
class RpcService;
class RpcServiceMethod;
class ServerCredentials;
class ThreadPoolInterface;

// Currently it only supports handling rpcs in a single thread.
class Server GRPC_FINAL : private CallHook,
                          private AsynchronousService::DispatchImpl {
 public:
  ~Server();

  // Shutdown the server, block until all rpc processing finishes.
  void Shutdown();

  // Block waiting for all work to complete (the server must either
  // be shutting down or some other thread must call Shutdown for this
  // function to ever return)
  void Wait();

  CompletionQueue* cq() { return &cq_; }

 private:
  friend class AsyncGenericService;
  friend class ServerBuilder;

  class SyncRequest;
  class AsyncRequest;

  // ServerBuilder use only
  Server(ThreadPoolInterface* thread_pool, bool thread_pool_owned);
  Server() = delete;
  // Register a service. This call does not take ownership of the service.
  // The service must exist for the lifetime of the Server instance.
  bool RegisterService(RpcService* service);
  bool RegisterAsyncService(AsynchronousService* service);
  void RegisterAsyncGenericService(AsyncGenericService* service);
  // Add a listening port. Can be called multiple times.
  int AddPort(const grpc::string& addr, ServerCredentials* creds);
  // Start the server.
  bool Start();

  void HandleQueueClosed();
  void RunRpc();
  void ScheduleCallback();

  void PerformOpsOnCall(CallOpBuffer* ops, Call* call) GRPC_OVERRIDE;

  // DispatchImpl
  void RequestAsyncCall(void* registered_method, ServerContext* context,
                        grpc::protobuf::Message* request,
                        ServerAsyncStreamingInterface* stream,
                        CompletionQueue* cq, void* tag) GRPC_OVERRIDE;

  void RequestAsyncGenericCall(GenericServerContext* context,
                               ServerAsyncStreamingInterface* stream,
                               CompletionQueue* cq, void* tag);

  // Completion queue.
  CompletionQueue cq_;

  // Sever status
  std::mutex mu_;
  bool started_;
  bool shutdown_;
  // The number of threads which are running callbacks.
  int num_running_cb_;
  std::condition_variable callback_cv_;

  std::list<SyncRequest> sync_methods_;

  // Pointer to the c grpc server.
  grpc_server* const server_;

  ThreadPoolInterface* thread_pool_;
  // Whether the thread pool is created and owned by the server.
  bool thread_pool_owned_;
};

}  // namespace grpc

#endif  // GRPCXX_SERVER_H