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//go:build !windows
package rawfilelock
import (
"time"
"golang.org/x/sys/unix"
)
type fileHandle uintptr
func openHandle(path string, mode int) (fileHandle, error) {
mode |= unix.O_CLOEXEC
fd, err := unix.Open(path, mode, 0o644)
return fileHandle(fd), err
}
func lockHandle(fd fileHandle, lType LockType, nonblocking bool) error {
fType := unix.F_RDLCK
if lType != ReadLock {
fType = unix.F_WRLCK
}
lk := unix.Flock_t{
Type: int16(fType),
Whence: int16(unix.SEEK_SET),
Start: 0,
Len: 0,
}
cmd := unix.F_SETLKW
if nonblocking {
cmd = unix.F_SETLK
}
for {
err := unix.FcntlFlock(uintptr(fd), cmd, &lk)
if err == nil || nonblocking {
return err
}
time.Sleep(10 * time.Millisecond)
}
}
func unlockAndCloseHandle(fd fileHandle) {
unix.Close(int(fd))
}
func closeHandle(fd fileHandle) {
unix.Close(int(fd))
}
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