lib/fs: harmonize CreateSymlink definitions (fixes #4567)

GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4632
LGTM: imsodin, AudriusButkevicius

lib/fs/basicfs_windows.go

@@ -28,7 +28,7 @@ func (BasicFilesystem) ReadSymlink(path string) (string, error) {
 	return "", errNotSupported
 }
 
-func (BasicFilesystem) CreateSymlink(path, target string) error {
+func (BasicFilesystem) CreateSymlink(target, name string) error {
 	return errNotSupported
 }
 

lib/fs/errorfs.go

@@ -20,7 +20,7 @@ type errorFilesystem struct {
 func (fs *errorFilesystem) Chmod(name string, mode FileMode) error                      { return fs.err }
 func (fs *errorFilesystem) Chtimes(name string, atime time.Time, mtime time.Time) error { return fs.err }
 func (fs *errorFilesystem) Create(name string) (File, error)                            { return nil, fs.err }
-func (fs *errorFilesystem) CreateSymlink(name, target string) error                     { return fs.err }
+func (fs *errorFilesystem) CreateSymlink(target, name string) error                     { return fs.err }
 func (fs *errorFilesystem) DirNames(name string) ([]string, error)                      { return nil, fs.err }
 func (fs *errorFilesystem) Lstat(name string) (FileInfo, error)                         { return nil, fs.err }
 func (fs *errorFilesystem) Mkdir(name string, perm FileMode) error                      { return fs.err }

lib/fs/filesystem.go

@@ -21,7 +21,7 @@ type Filesystem interface {
 	Chmod(name string, mode FileMode) error
 	Chtimes(name string, atime time.Time, mtime time.Time) error
 	Create(name string) (File, error)
-	CreateSymlink(name, target string) error
+	CreateSymlink(target, name string) error
 	DirNames(name string) ([]string, error)
 	Lstat(name string) (FileInfo, error)
 	Mkdir(name string, perm FileMode) error

lib/fs/logfs.go

@@ -44,9 +44,9 @@ func (fs *logFilesystem) Create(name string) (File, error) {
 	return file, err
 }
 
-func (fs *logFilesystem) CreateSymlink(name, target string) error {
-	err := fs.Filesystem.CreateSymlink(name, target)
-	l.Debugln(getCaller(), fs.Type(), fs.URI(), "CreateSymlink", name, target, err)
+func (fs *logFilesystem) CreateSymlink(target, name string) error {
+	err := fs.Filesystem.CreateSymlink(target, name)
+	l.Debugln(getCaller(), fs.Type(), fs.URI(), "CreateSymlink", target, name, err)
 	return err
 }