| 1 | //go:build windows |
| 2 | |
| 3 | package filelock |
| 4 | |
| 5 | import ( |
| 6 | "errors" |
| 7 | "os" |
| 8 | |
| 9 | "golang.org/x/sys/windows" |
| 10 | ) |
| 11 | |
| 12 | func tryLockFile(path string) (func(), error) { |
| 13 | return tryLockFileMode(path, ModeExclusive) |
| 14 | } |
| 15 | |
| 16 | func tryLockFileMode(path string, mode Mode) (func(), error) { |
| 17 | f, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR, 0o600) |
| 18 | if err != nil { |
| 19 | if errors.Is(err, windows.ERROR_SHARING_VIOLATION) { |
| 20 | return nil, ErrHeld |
| 21 | } |
| 22 | return nil, err |
| 23 | } |
| 24 | handle := windows.Handle(f.Fd()) |
| 25 | var overlapped windows.Overlapped |
| 26 | flags := uint32(windows.LOCKFILE_EXCLUSIVE_LOCK | windows.LOCKFILE_FAIL_IMMEDIATELY) |
| 27 | if mode == ModeShared { |
| 28 | flags = uint32(windows.LOCKFILE_FAIL_IMMEDIATELY) |
| 29 | } |
| 30 | if err := windows.LockFileEx(handle, flags, 0, 1, 0, &overlapped); err != nil { |
| 31 | _ = f.Close() |
| 32 | if errors.Is(err, windows.ERROR_LOCK_VIOLATION) || errors.Is(err, windows.ERROR_SHARING_VIOLATION) { |
| 33 | return nil, ErrHeld |
| 34 | } |
| 35 | return nil, err |
| 36 | } |
| 37 | return func() { |
| 38 | _ = windows.UnlockFileEx(handle, 0, 1, 0, &overlapped) |
| 39 | _ = f.Close() |
| 40 | }, nil |
| 41 | } |
| 42 |