client/pkg/fileutil: use golang.org/x/sys/windows for FileLockEx
Use the FileLockEx wrapper and the corresponding LOCKFILE_* and error
constants from the golang.org/x/sys/windows package rather than
implementing these in the fileutil package.
@@ -22,31 +22,18 @@ import (
"fmt"
"os"
"syscall"
- "unsafe"
-)
-
-var (
- modkernel32 = syscall.NewLazyDLL("kernel32.dll")
- procLockFileEx = modkernel32.NewProc("LockFileEx")
- errLocked = errors.New("the process cannot access the file because another process has locked a portion of the file")
+ "golang.org/x/sys/windows"
)
-const (
- // https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
- LOCKFILE_EXCLUSIVE_LOCK = 2
- LOCKFILE_FAIL_IMMEDIATELY = 1
-
- // see https://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx
- errLockViolation syscall.Errno = 0x21
-)
+var errLocked = errors.New("the process cannot access the file because another process has locked a portion of the file")
func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
f, err := open(path, flag, perm)
if err != nil {
return nil, err
}
- if err := lockFile(syscall.Handle(f.Fd()), LOCKFILE_FAIL_IMMEDIATELY); err != nil {
+ if err := lockFile(windows.Handle(f.Fd()), windows.LOCKFILE_FAIL_IMMEDIATELY); err != nil {
f.Close()
return nil, err
}
@@ -58,7 +45,7 @@ func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
if err != nil {
return nil, err
}
- if err := lockFile(syscall.Handle(f.Fd()), 0); err != nil {
+ if err := lockFile(windows.Handle(f.Fd()), 0); err != nil {
f.Close()
return nil, err
}
@@ -95,32 +82,17 @@ func open(path string, flag int, perm os.FileMode) (*os.File, error) {
return os.NewFile(uintptr(fd), path), nil
}
-func lockFile(fd syscall.Handle, flags uint32) error {
- var flag uint32 = LOCKFILE_EXCLUSIVE_LOCK
- flag |= flags
- if fd == syscall.InvalidHandle {
+func lockFile(fd windows.Handle, flags uint32) error {
+ if fd == windows.InvalidHandle {
return nil
}
- err := lockFileEx(fd, flag, 1, 0, &syscall.Overlapped{})
+ err := windows.LockFileEx(fd, flags|windows.LOCKFILE_EXCLUSIVE_LOCK, 0, 1, 0, &windows.Overlapped{})
if err == nil {
return nil
} else if err.Error() == errLocked.Error() {
return ErrLocked
- } else if err != errLockViolation {
+ } else if err != windows.ERROR_LOCK_VIOLATION {
return err
}
return nil
}
-
-func lockFileEx(h syscall.Handle, flags, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
- var reserved uint32 = 0
- r1, _, e1 := syscall.Syscall6(procLockFileEx.Addr(), 6, uintptr(h), uintptr(flags), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
- if r1 == 0 {
- if e1 != 0 {
- err = error(e1)
- } else {
- err = syscall.EINVAL
- }
- }
- return err
-}
