/* * Minio Cloud Storage, (C) 2015 Minio, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package fs import ( "errors" "os" "path/filepath" "sort" ) // Walk walks the file tree rooted at root, calling walkFn for each file or // directory in the tree, including root. func Walk(root string, walkFn WalkFunc) error { info, err := os.Lstat(root) if err != nil { return walkFn(root, nil, err) } return walk(root, info, walkFn) } // readDirNames reads the directory named by dirname and returns // a sorted list of directory entries. func readDirNames(dirname string) ([]string, error) { f, err := os.Open(dirname) if err != nil { return nil, err } names, err := f.Readdirnames(-1) f.Close() if err != nil { return nil, err } sort.Strings(names) return names, nil } // WalkFunc is the type of the function called for each file or directory // visited by Walk. The path argument contains the argument to Walk as a // prefix; that is, if Walk is called with "dir", which is a directory // containing the file "a", the walk function will be called with argument // "dir/a". The info argument is the os.FileInfo for the named path. type WalkFunc func(path string, info os.FileInfo, err error) error // ErrSkipDir is used as a return value from WalkFuncs to indicate that // the directory named in the call is to be skipped. It is not returned // as an error by any function. var ErrSkipDir = errors.New("skip this directory") // ErrSkipFile is used as a return value from WalkFuncs to indicate that // the file named in the call is to be skipped. It is not returned // as an error by any function. var ErrSkipFile = errors.New("skip this file") // walk recursively descends path, calling w. func walk(path string, info os.FileInfo, walkFn WalkFunc) error { err := walkFn(path, info, nil) if err != nil { if info.Mode().IsDir() && err == ErrSkipDir { return nil } if info.Mode().IsRegular() && err == ErrSkipFile { return nil } return err } if !info.IsDir() { return nil } names, err := readDirNames(path) if err != nil { return walkFn(path, info, err) } for _, name := range names { filename := filepath.Join(path, name) fileInfo, err := os.Lstat(filename) if err != nil { if err := walkFn(filename, fileInfo, err); err != nil && err != ErrSkipDir && err != ErrSkipFile { return err } } else { err = walk(filename, fileInfo, walkFn) if err != nil { if err == ErrSkipDir || err == ErrSkipFile { return nil } return err } } } return nil }