src/cpp/common/completion_queue_cc.cc

/*
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#include <grpc++/completion_queue.h>

#include <memory>

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

namespace grpc {

static internal::GrpcLibraryInitializer g_gli_initializer;

CompletionQueue::CompletionQueue(grpc_completion_queue* take) : cq_(take) {
  InitialAvalanching();
}

void CompletionQueue::Shutdown() {
  g_gli_initializer.summon();
  CompleteAvalanching();
}

void CompletionQueue::CompleteAvalanching() {
  // Check if this was the last avalanching operation
  if (gpr_atm_no_barrier_fetch_add(&avalanches_in_flight_,
                                   static_cast<gpr_atm>(-1)) == 1) {
    grpc_completion_queue_shutdown(cq_);
  }
}

CompletionQueue::NextStatus CompletionQueue::AsyncNextInternal(
    void** tag, bool* ok, gpr_timespec deadline) {
  for (;;) {
    auto ev = grpc_completion_queue_next(cq_, deadline, nullptr);
    switch (ev.type) {
      case GRPC_QUEUE_TIMEOUT:
        return TIMEOUT;
      case GRPC_QUEUE_SHUTDOWN:
        return SHUTDOWN;
      case GRPC_OP_COMPLETE:
        auto cq_tag = static_cast<CompletionQueueTag*>(ev.tag);
        *ok = ev.success != 0;
        *tag = cq_tag;
        if (cq_tag->FinalizeResult(tag, ok)) {
          return GOT_EVENT;
        }
        break;
    }
  }
}

}  // namespace grpc