| // Copyright 2018 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // +build darwin dragonfly freebsd hurd illumos linux netbsd openbsd |
| |
| package filelock |
| |
| import ( |
| "io/fs" |
| "syscall" |
| ) |
| |
| type lockType int16 |
| |
| const ( |
| readLock lockType = syscall.LOCK_SH |
| writeLock lockType = syscall.LOCK_EX |
| ) |
| |
| func lock(f File, lt lockType) (err error) { |
| for { |
| err = syscall.Flock(int(f.Fd()), int(lt)) |
| if err != syscall.EINTR { |
| break |
| } |
| } |
| if err != nil { |
| return &fs.PathError{ |
| Op: lt.String(), |
| Path: f.Name(), |
| Err: err, |
| } |
| } |
| return nil |
| } |
| |
| func unlock(f File) error { |
| return lock(f, syscall.LOCK_UN) |
| } |
| |
| func isNotSupported(err error) bool { |
| return err == syscall.ENOSYS || err == syscall.ENOTSUP || err == syscall.EOPNOTSUPP || err == ErrNotSupported |
| } |
