rocksdb/util/random.cc
Daniel Black bfbcec2339 Gcc 7 error expansion to defined
Summary:
sorry if these gcc-7/clang-4 cleanups are getting tedious.
Closes https://github.com/facebook/rocksdb/pull/1658

Differential Revision: D4318792

Pulled By: yiwu-arbug

fbshipit-source-id: 8e85891
2016-12-13 18:39:14 -08:00

39 lines
1013 B
C++

// 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.
//
#include "util/random.h"
#include <stdint.h>
#include <string.h>
#include <thread>
#include <utility>
#include "port/likely.h"
#include "util/thread_local.h"
#ifdef ROCKSDB_SUPPORT_THREAD_LOCAL
#define STORAGE_DECL static __thread
#else
#define STORAGE_DECL static
#endif
namespace rocksdb {
Random* Random::GetTLSInstance() {
STORAGE_DECL Random* tls_instance;
STORAGE_DECL std::aligned_storage<sizeof(Random)>::type tls_instance_bytes;
auto rv = tls_instance;
if (UNLIKELY(rv == nullptr)) {
size_t seed = std::hash<std::thread::id>()(std::this_thread::get_id());
rv = new (&tls_instance_bytes) Random((uint32_t)seed);
tls_instance = rv;
}
return rv;
}
} // namespace rocksdb