emptyvfs.go

Documentation: golang.org/x/tools/godoc/vfs

     1  // Copyright 2016 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package vfs
     6  
     7  import (
     8  	"fmt"
     9  	"os"
    10  	"time"
    11  )
    12  
    13  // NewNameSpace returns a NameSpace pre-initialized with an empty
    14  // emulated directory mounted on the root mount point "/". This
    15  // allows directory traversal routines to work properly even if
    16  // a folder is not explicitly mounted at root by the user.
    17  func NewNameSpace() NameSpace {
    18  	ns := NameSpace{}
    19  	ns.Bind("/", &emptyVFS{}, "/", BindReplace)
    20  	return ns
    21  }
    22  
    23  // type emptyVFS emulates a FileSystem consisting of an empty directory
    24  type emptyVFS struct{}
    25  
    26  // Open implements Opener. Since emptyVFS is an empty directory, all
    27  // attempts to open a file should returns errors.
    28  func (e *emptyVFS) Open(path string) (ReadSeekCloser, error) {
    29  	if path == "/" {
    30  		return nil, fmt.Errorf("open: / is a directory")
    31  	}
    32  	return nil, os.ErrNotExist
    33  }
    34  
    35  // Stat returns os.FileInfo for an empty directory if the path is
    36  // is root "/" or error. os.FileInfo is implemented by emptyVFS
    37  func (e *emptyVFS) Stat(path string) (os.FileInfo, error) {
    38  	if path == "/" {
    39  		return e, nil
    40  	}
    41  	return nil, os.ErrNotExist
    42  }
    43  
    44  func (e *emptyVFS) Lstat(path string) (os.FileInfo, error) {
    45  	return e.Stat(path)
    46  }
    47  
    48  // ReadDir returns an empty os.FileInfo slice for "/", else error.
    49  func (e *emptyVFS) ReadDir(path string) ([]os.FileInfo, error) {
    50  	if path == "/" {
    51  		return []os.FileInfo{}, nil
    52  	}
    53  	return nil, os.ErrNotExist
    54  }
    55  
    56  func (e *emptyVFS) String() string {
    57  	return "emptyVFS(/)"
    58  }
    59  
    60  func (e *emptyVFS) RootType(path string) RootType {
    61  	return ""
    62  }
    63  
    64  // These functions below implement os.FileInfo for the single
    65  // empty emulated directory.
    66  
    67  func (e *emptyVFS) Name() string {
    68  	return "/"
    69  }
    70  
    71  func (e *emptyVFS) Size() int64 {
    72  	return 0
    73  }
    74  
    75  func (e *emptyVFS) Mode() os.FileMode {
    76  	return os.ModeDir | os.ModePerm
    77  }
    78  
    79  func (e *emptyVFS) ModTime() time.Time {
    80  	return time.Time{}
    81  }
    82  
    83  func (e *emptyVFS) IsDir() bool {
    84  	return true
    85  }
    86  
    87  func (e *emptyVFS) Sys() interface{} {
    88  	return nil
    89  }
    90
View as plain text