src/cpp/server/server_context.cc

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#include <grpc++/server_context.h>

#include <grpc/grpc.h>
#include <grpc/support/log.h>
#include <grpc++/impl/call.h>
#include <grpc++/impl/sync.h>
#include <grpc++/time.h>

#include "src/cpp/common/create_auth_context.h"

namespace grpc {

// CompletionOp

class ServerContext::CompletionOp GRPC_FINAL : public CallOpSetInterface {
 public:
  // initial refs: one in the server context, one in the cq
  CompletionOp() : refs_(2), finalized_(false), cancelled_(0) {}

  void FillOps(grpc_op* ops, size_t* nops) GRPC_OVERRIDE;
  bool FinalizeResult(void** tag, bool* status) GRPC_OVERRIDE;

  bool CheckCancelled(CompletionQueue* cq);

  void Unref();

 private:
  grpc::mutex mu_;
  int refs_;
  bool finalized_;
  int cancelled_;
};

void ServerContext::CompletionOp::Unref() {
  grpc::unique_lock<grpc::mutex> lock(mu_);
  if (--refs_ == 0) {
    lock.unlock();
    delete this;
  }
}

bool ServerContext::CompletionOp::CheckCancelled(CompletionQueue* cq) {
  cq->TryPluck(this);
  grpc::lock_guard<grpc::mutex> g(mu_);
  return finalized_ ? cancelled_ != 0 : false;
}

void ServerContext::CompletionOp::FillOps(grpc_op* ops, size_t* nops) {
  ops->op = GRPC_OP_RECV_CLOSE_ON_SERVER;
  ops->data.recv_close_on_server.cancelled = &cancelled_;
  ops->flags = 0;
  *nops = 1;
}

bool ServerContext::CompletionOp::FinalizeResult(void** tag, bool* status) {
  grpc::unique_lock<grpc::mutex> lock(mu_);
  finalized_ = true;
  if (!*status) cancelled_ = 1;
  if (--refs_ == 0) {
    lock.unlock();
    delete this;
  }
  return false;
}

// ServerContext body

ServerContext::ServerContext()
    : completion_op_(nullptr),
      call_(nullptr),
      cq_(nullptr),
      sent_initial_metadata_(false) {}

ServerContext::ServerContext(gpr_timespec deadline, grpc_metadata* metadata,
                             size_t metadata_count)
    : completion_op_(nullptr),
      deadline_(deadline),
      call_(nullptr),
      cq_(nullptr),
      sent_initial_metadata_(false) {
  for (size_t i = 0; i < metadata_count; i++) {
    client_metadata_.insert(std::make_pair(
        grpc::string(metadata[i].key),
        grpc::string(metadata[i].value,
                     metadata[i].value + metadata[i].value_length)));
  }
}

ServerContext::~ServerContext() {
  if (call_) {
    grpc_call_destroy(call_);
  }
  if (completion_op_) {
    completion_op_->Unref();
  }
}

void ServerContext::BeginCompletionOp(Call* call) {
  GPR_ASSERT(!completion_op_);
  completion_op_ = new CompletionOp();
  call->PerformOps(completion_op_);
}

void ServerContext::AddInitialMetadata(const grpc::string& key,
                                       const grpc::string& value) {
  initial_metadata_.insert(std::make_pair(key, value));
}

void ServerContext::AddTrailingMetadata(const grpc::string& key,
                                        const grpc::string& value) {
  trailing_metadata_.insert(std::make_pair(key, value));
}

bool ServerContext::IsCancelled() {
  return completion_op_ && completion_op_->CheckCancelled(cq_);
}

void ServerContext::set_call(grpc_call* call) {
  call_ = call;
  auth_context_ = CreateAuthContext(call);
}

}  // namespace grpc