1/* 2Copyright (c) for portions of walk.go are held by The Go Authors, 2009 and are 3provided under the BSD license. 4 5https://github.com/golang/go/blob/master/LICENSE 6 7Copyright The Helm Authors. 8Licensed under the Apache License, Version 2.0 (the "License"); 9you may not use this file except in compliance with the License. 10You may obtain a copy of the License at 11 12http://www.apache.org/licenses/LICENSE-2.0 13 14Unless required by applicable law or agreed to in writing, software 15distributed under the License is distributed on an "AS IS" BASIS, 16WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 17See the License for the specific language governing permissions and 18limitations under the License. 19*/ 20 21package sympath 22 23import ( 24 "log" 25 "os" 26 "path/filepath" 27 "sort" 28 29 "github.com/pkg/errors" 30) 31 32// Walk walks the file tree rooted at root, calling walkFn for each file or directory 33// in the tree, including root. All errors that arise visiting files and directories 34// are filtered by walkFn. The files are walked in lexical order, which makes the 35// output deterministic but means that for very large directories Walk can be 36// inefficient. Walk follows symbolic links. 37func Walk(root string, walkFn filepath.WalkFunc) error { 38 info, err := os.Lstat(root) 39 if err != nil { 40 err = walkFn(root, nil, err) 41 } else { 42 err = symwalk(root, info, walkFn) 43 } 44 if err == filepath.SkipDir { 45 return nil 46 } 47 return err 48} 49 50// readDirNames reads the directory named by dirname and returns 51// a sorted list of directory entries. 52func readDirNames(dirname string) ([]string, error) { 53 f, err := os.Open(dirname) 54 if err != nil { 55 return nil, err 56 } 57 names, err := f.Readdirnames(-1) 58 f.Close() 59 if err != nil { 60 return nil, err 61 } 62 sort.Strings(names) 63 return names, nil 64} 65 66// symwalk recursively descends path, calling walkFn. 67func symwalk(path string, info os.FileInfo, walkFn filepath.WalkFunc) error { 68 // Recursively walk symlinked directories. 69 if IsSymlink(info) { 70 resolved, err := filepath.EvalSymlinks(path) 71 if err != nil { 72 return errors.Wrapf(err, "error evaluating symlink %s", path) 73 } 74 log.Printf("found symbolic link in path: %s resolves to %s", path, resolved) 75 if info, err = os.Lstat(resolved); err != nil { 76 return err 77 } 78 if err := symwalk(path, info, walkFn); err != nil && err != filepath.SkipDir { 79 return err 80 } 81 return nil 82 } 83 84 if err := walkFn(path, info, nil); err != nil { 85 return err 86 } 87 88 if !info.IsDir() { 89 return nil 90 } 91 92 names, err := readDirNames(path) 93 if err != nil { 94 return walkFn(path, info, err) 95 } 96 97 for _, name := range names { 98 filename := filepath.Join(path, name) 99 fileInfo, err := os.Lstat(filename) 100 if err != nil { 101 if err := walkFn(filename, fileInfo, err); err != nil && err != filepath.SkipDir { 102 return err 103 } 104 } else { 105 err = symwalk(filename, fileInfo, walkFn) 106 if err != nil { 107 if (!fileInfo.IsDir() && !IsSymlink(fileInfo)) || err != filepath.SkipDir { 108 return err 109 } 110 } 111 } 112 } 113 return nil 114} 115 116// IsSymlink is used to determine if the fileinfo is a symbolic link. 117func IsSymlink(fi os.FileInfo) bool { 118 return fi.Mode()&os.ModeSymlink != 0 119} 120