vendor/github.com/spf13/afero/path.go

   1 // Copyright ©2015 The Go Authors
   2 // Copyright ©2015 Steve Francia <spf@spf13.com>
   3 //
   4 // Licensed under the Apache License, Version 2.0 (the "License");
   5 // you may not use this file except in compliance with the License.
   6 // You may obtain a copy of the License at
   7 //
   8 //     http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15
  16 package afero
  17
  18 import (
  19         "os"
  20         "path/filepath"
  21         "sort"
  22 )
  23
  24 // readDirNames reads the directory named by dirname and returns
  25 // a sorted list of directory entries.
  26 // adapted from https://golang.org/src/path/filepath/path.go
  27 func readDirNames(fs Fs, dirname string) ([]string, error) {
  28         f, err := fs.Open(dirname)
  29         if err != nil {
  30                 return nil, err
  31         }
  32         names, err := f.Readdirnames(-1)
  33         f.Close()
  34         if err != nil {
  35                 return nil, err
  36         }
  37         sort.Strings(names)
  38         return names, nil
  39 }
  40
  41 // walk recursively descends path, calling walkFn
  42 // adapted from https://golang.org/src/path/filepath/path.go
  43 func walk(fs Fs, path string, info os.FileInfo, walkFn filepath.WalkFunc) error {
  44         err := walkFn(path, info, nil)
  45         if err != nil {
  46                 if info.IsDir() && err == filepath.SkipDir {
  47                         return nil
  48                 }
  49                 return err
  50         }
  51
  52         if !info.IsDir() {
  53                 return nil
  54         }
  55
  56         names, err := readDirNames(fs, path)
  57         if err != nil {
  58                 return walkFn(path, info, err)
  59         }
  60
  61         for _, name := range names {
  62                 filename := filepath.Join(path, name)
  63                 fileInfo, err := lstatIfPossible(fs, filename)
  64                 if err != nil {
  65                         if err := walkFn(filename, fileInfo, err); err != nil && err != filepath.SkipDir {
  66                                 return err
  67                         }
  68                 } else {
  69                         err = walk(fs, filename, fileInfo, walkFn)
  70                         if err != nil {
  71                                 if !fileInfo.IsDir() || err != filepath.SkipDir {
  72                                         return err
  73                                 }
  74                         }
  75                 }
  76         }
  77         return nil
  78 }
  79
  80 // if the filesystem supports it, use Lstat, else use fs.Stat
  81 func lstatIfPossible(fs Fs, path string) (os.FileInfo, error) {
  82         if lfs, ok := fs.(Lstater); ok {
  83                 fi, _, err := lfs.LstatIfPossible(path)
  84                 return fi, err
  85         }
  86         return fs.Stat(path)
  87 }
  88
  89 // Walk walks the file tree rooted at root, calling walkFn for each file or
  90 // directory in the tree, including root. All errors that arise visiting files
  91 // and directories are filtered by walkFn. The files are walked in lexical
  92 // order, which makes the output deterministic but means that for very
  93 // large directories Walk can be inefficient.
  94 // Walk does not follow symbolic links.
  95
  96 func (a Afero) Walk(root string, walkFn filepath.WalkFunc) error {
  97         return Walk(a.Fs, root, walkFn)
  98 }
  99
 100 func Walk(fs Fs, root string, walkFn filepath.WalkFunc) error {
 101         info, err := lstatIfPossible(fs, root)
 102         if err != nil {
 103                 return walkFn(root, nil, err)
 104         }
 105         return walk(fs, root, info, walkFn)
 106 }