rocksdb/port/win/env_default.cc

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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
// This source code is also licensed under the GPLv2 license found in the
// COPYING file in the root directory of this source tree.
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include <mutex>
#include <rocksdb/env.h>
#include "port/win/env_win.h"
namespace rocksdb {
namespace port {
// We choose to create this on the heap and using std::once for the following
// reasons
// 1) Currently available MS compiler does not implement atomic C++11
// initialization of
// function local statics
// 2) We choose not to destroy the env because joining the threads from the
// system loader
// which destroys the statics (same as from DLLMain) creates a system loader
// dead-lock.
// in this manner any remaining threads are terminated OK.
namespace {
std::once_flag winenv_once_flag;
Env* envptr;
};
}
Env* Env::Default() {
using namespace port;
std::call_once(winenv_once_flag, []() { envptr = new WinEnv(); });
return envptr;
}
}