Verify Windows support, report appropriate errors when unsupported

This commit is contained in:
Jakob Borg 2014-12-04 12:08:04 +01:00
parent 2abe792f36
commit 5af6cbae2c

View File

@ -16,7 +16,9 @@
package symlinks
import (
"errors"
"os"
"path/filepath"
"runtime"
"github.com/syncthing/syncthing/internal/osutil"
@ -24,10 +26,19 @@ import (
)
var (
Supported = true
Supported = false
ErrUnsupported = errors.New("symlinks not supported")
)
func init() {
Supported = symlinksSupported()
}
func Read(path string) (string, uint32, error) {
if !Supported {
return "", 0, ErrUnsupported
}
var mode uint32
stat, err := os.Stat(path)
if err != nil {
@ -41,6 +52,10 @@ func Read(path string) (string, uint32, error) {
}
func IsSymlink(path string) (bool, error) {
if !Supported {
return false, ErrUnsupported
}
lstat, err := os.Lstat(path)
if err != nil {
return false, err
@ -49,6 +64,10 @@ func IsSymlink(path string) (bool, error) {
}
func Create(target, source string, flags uint32) error {
if !Supported {
return ErrUnsupported
}
return os.Symlink(osutil.NativeFilename(target), source)
}
@ -58,6 +77,10 @@ func ChangeType(path string, flags uint32) error {
return nil
}
if !Supported {
return ErrUnsupported
}
target, cflags, err := Read(path)
if err != nil {
return err
@ -80,3 +103,36 @@ func ChangeType(path string, flags uint32) error {
return Create(target, path, flags)
}, path)
}
func symlinksSupported() bool {
if runtime.GOOS != "windows" {
// Symlinks are supported. In practice there may be deviations (FAT
// filesystems etc), but these get handled and reported as the errors
// they are when they happen.
return true
}
// We try to create a symlink and verify that it looks like we expected.
// Needs administrator priviledges and a version higher than XP.
base := os.TempDir()
path := filepath.Join(base, "syncthing-symlink-test")
defer os.Remove(path)
err := Create(base, path, protocol.FlagDirectory)
if err != nil {
return false
}
isLink, err := IsSymlink(path)
if err != nil || !isLink {
return false
}
target, flags, err := Read(path)
if err != nil || osutil.NativeFilename(target) != base || flags&protocol.FlagDirectory == 0 {
return false
}
return true
}