ipld-eth-server/vendor/golang.org/x/tools/godoc/vfs/emptyvfs.go
2018-08-07 10:51:34 -05:00

90 lines
2.0 KiB
Go

// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package vfs
import (
"fmt"
"os"
"time"
)
// NewNameSpace returns a NameSpace pre-initialized with an empty
// emulated directory mounted on the root mount point "/". This
// allows directory traversal routines to work properly even if
// a folder is not explicitly mounted at root by the user.
func NewNameSpace() NameSpace {
ns := NameSpace{}
ns.Bind("/", &emptyVFS{}, "/", BindReplace)
return ns
}
// type emptyVFS emulates a FileSystem consisting of an empty directory
type emptyVFS struct{}
// Open implements Opener. Since emptyVFS is an empty directory, all
// attempts to open a file should returns errors.
func (e *emptyVFS) Open(path string) (ReadSeekCloser, error) {
if path == "/" {
return nil, fmt.Errorf("open: / is a directory")
}
return nil, os.ErrNotExist
}
// Stat returns os.FileInfo for an empty directory if the path is
// is root "/" or error. os.FileInfo is implemented by emptyVFS
func (e *emptyVFS) Stat(path string) (os.FileInfo, error) {
if path == "/" {
return e, nil
}
return nil, os.ErrNotExist
}
func (e *emptyVFS) Lstat(path string) (os.FileInfo, error) {
return e.Stat(path)
}
// ReadDir returns an empty os.FileInfo slice for "/", else error.
func (e *emptyVFS) ReadDir(path string) ([]os.FileInfo, error) {
if path == "/" {
return []os.FileInfo{}, nil
}
return nil, os.ErrNotExist
}
func (e *emptyVFS) String() string {
return "emptyVFS(/)"
}
func (e *emptyVFS) RootType(path string) RootType {
return ""
}
// These functions below implement os.FileInfo for the single
// empty emulated directory.
func (e *emptyVFS) Name() string {
return "/"
}
func (e *emptyVFS) Size() int64 {
return 0
}
func (e *emptyVFS) Mode() os.FileMode {
return os.ModeDir | os.ModePerm
}
func (e *emptyVFS) ModTime() time.Time {
return time.Time{}
}
func (e *emptyVFS) IsDir() bool {
return true
}
func (e *emptyVFS) Sys() interface{} {
return nil
}