1 | /* |
2 | * Copyright 2016-present Facebook, Inc. |
3 | * |
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 |
7 | * |
8 | * http://www.apache.org/licenses/LICENSE-2.0 |
9 | * |
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. |
15 | */ |
16 | |
17 | #include <folly/portability/SysFile.h> |
18 | |
19 | #ifdef _WIN32 |
20 | #include <limits> |
21 | |
22 | #include <folly/portability/Windows.h> |
23 | |
24 | extern "C" int flock(int fd, int operation) { |
25 | HANDLE h = (HANDLE)_get_osfhandle(fd); |
26 | if (h == INVALID_HANDLE_VALUE) { |
27 | return -1; |
28 | } |
29 | |
30 | constexpr DWORD kMaxDWORD = std::numeric_limits<DWORD>::max(); |
31 | if (operation & LOCK_UN) { |
32 | if (!UnlockFile(h, 0, 0, kMaxDWORD, kMaxDWORD)) { |
33 | return -1; |
34 | } |
35 | } else { |
36 | DWORD flags = DWORD( |
37 | (operation & LOCK_NB ? LOCKFILE_FAIL_IMMEDIATELY : 0) | |
38 | (operation & LOCK_EX ? LOCKFILE_EXCLUSIVE_LOCK : 0)); |
39 | OVERLAPPED ov = {}; |
40 | if (!LockFileEx(h, flags, 0, kMaxDWORD, kMaxDWORD, &ov)) { |
41 | return -1; |
42 | } |
43 | } |
44 | return 0; |
45 | } |
46 | #endif |
47 | |