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|
//go:build !sqlite3_flock
package vfs
import (
"io"
"os"
"time"
"golang.org/x/sys/unix"
)
func osSync(file *os.File, _ /*fullsync*/, _ /*dataonly*/ bool) error {
// SQLite trusts Linux's fdatasync for all fsync's.
for {
err := unix.Fdatasync(int(file.Fd()))
if err != unix.EINTR {
return err
}
}
}
func osAllocate(file *os.File, size int64) error {
if size == 0 {
return nil
}
for {
err := unix.Fallocate(int(file.Fd()), 0, 0, size)
if err == unix.EOPNOTSUPP {
break
}
if err != unix.EINTR {
return err
}
}
off, err := file.Seek(0, io.SeekEnd)
if err != nil {
return err
}
if size <= off {
return nil
}
return file.Truncate(size)
}
func osReadLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
return osLock(file, unix.F_RDLCK, start, len, timeout, _IOERR_RDLOCK)
}
func osWriteLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
return osLock(file, unix.F_WRLCK, start, len, timeout, _IOERR_LOCK)
}
func osLock(file *os.File, typ int16, start, len int64, timeout time.Duration, def _ErrorCode) _ErrorCode {
lock := unix.Flock_t{
Type: typ,
Start: start,
Len: len,
}
var err error
switch {
default:
err = unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLK, &lock)
case timeout < 0:
err = unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLKW, &lock)
}
return osLockErrorCode(err, def)
}
func osUnlock(file *os.File, start, len int64) _ErrorCode {
lock := unix.Flock_t{
Type: unix.F_UNLCK,
Start: start,
Len: len,
}
for {
err := unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLK, &lock)
if err == nil {
return _OK
}
if err != unix.EINTR {
return _IOERR_UNLOCK
}
}
}
|
