src/node/ext/completion_queue_async_worker.cc

/*
 *
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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#include <node.h>
#include <nan.h>

#include "grpc/grpc.h"
#include "grpc/support/time.h"
#include "completion_queue_async_worker.h"
#include "event.h"
#include "tag.h"

namespace grpc {
namespace node {

const int max_queue_threads = 2;

using v8::Function;
using v8::Handle;
using v8::Object;
using v8::Persistent;
using v8::Value;

grpc_completion_queue *CompletionQueueAsyncWorker::queue;

int CompletionQueueAsyncWorker::current_threads;
int CompletionQueueAsyncWorker::waiting_next_calls;

CompletionQueueAsyncWorker::CompletionQueueAsyncWorker()
    : NanAsyncWorker(NULL) {}

CompletionQueueAsyncWorker::~CompletionQueueAsyncWorker() {}

void CompletionQueueAsyncWorker::Execute() {
  result = grpc_completion_queue_next(queue, gpr_inf_future);
}

grpc_completion_queue *CompletionQueueAsyncWorker::GetQueue() { return queue; }

void CompletionQueueAsyncWorker::Next() {
  NanScope();
  if (current_threads < max_queue_threads) {
    CompletionQueueAsyncWorker *worker = new CompletionQueueAsyncWorker();
    NanAsyncQueueWorker(worker);
  } else {
    waiting_next_calls += 1;
  }
}

void CompletionQueueAsyncWorker::Init(Handle<Object> exports) {
  NanScope();
  current_threads = 0;
  waiting_next_calls = 0;
  queue = grpc_completion_queue_create();
}

void CompletionQueueAsyncWorker::HandleOKCallback() {
  NanScope();
  if (waiting_next_calls > 0) {
    waiting_next_calls -= 1;
    CompletionQueueAsyncWorker *worker = new CompletionQueueAsyncWorker();
    NanAsyncQueueWorker(worker);
  } else {
    current_threads -= 1;
  }
  NanCallback event_callback(GetTagHandle(result->tag).As<Function>());
  Handle<Value> argv[] = {CreateEventObject(result)};

  DestroyTag(result->tag);
  grpc_event_finish(result);
  result = NULL;

  event_callback.Call(1, argv);
}

}  // namespace node
}  // namespace grpc