2 * Copyright 2016 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #include <folly/portability/SysFile.h>
22 #include <folly/portability/Windows.h>
24 extern "C" int flock(int fd, int operation) {
25 HANDLE h = (HANDLE)_get_osfhandle(fd);
26 if (h == INVALID_HANDLE_VALUE) {
30 constexpr DWORD kMaxDWORD = std::numeric_limits<DWORD>::max();
31 if (operation & LOCK_UN) {
32 if (!UnlockFile(h, 0, 0, kMaxDWORD, kMaxDWORD)) {
37 | (operation & LOCK_NB ? LOCKFILE_FAIL_IMMEDIATELY : 0)
38 | (operation & LOCK_EX ? LOCKFILE_EXCLUSIVE_LOCK : 0)
41 if (!LockFileEx(h, flags, 0, kMaxDWORD, kMaxDWORD, &ov)) {