summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/spf13/afero/basepath.go
blob: 616ff8ff74c5326169f257519571a45f99629c59 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
package afero

import (
	"os"
	"path/filepath"
	"runtime"
	"strings"
	"time"
)

var _ Lstater = (*BasePathFs)(nil)

// The BasePathFs restricts all operations to a given path within an Fs.
// The given file name to the operations on this Fs will be prepended with
// the base path before calling the base Fs.
// Any file name (after filepath.Clean()) outside this base path will be
// treated as non existing file.
//
// Note that it does not clean the error messages on return, so you may
// reveal the real path on errors.
type BasePathFs struct {
	source Fs
	path   string
}

type BasePathFile struct {
	File
	path string
}

func (f *BasePathFile) Name() string {
	sourcename := f.File.Name()
	return strings.TrimPrefix(sourcename, filepath.Clean(f.path))
}

func NewBasePathFs(source Fs, path string) Fs {
	return &BasePathFs{source: source, path: path}
}

// on a file outside the base path it returns the given file name and an error,
// else the given file with the base path prepended
func (b *BasePathFs) RealPath(name string) (path string, err error) {
	if err := validateBasePathName(name); err != nil {
		return name, err
	}

	bpath := filepath.Clean(b.path)
	path = filepath.Clean(filepath.Join(bpath, name))
	if !strings.HasPrefix(path, bpath) {
		return name, os.ErrNotExist
	}

	return path, nil
}

func validateBasePathName(name string) error {
	if runtime.GOOS != "windows" {
		// Not much to do here;
		// the virtual file paths all look absolute on *nix.
		return nil
	}

	// On Windows a common mistake would be to provide an absolute OS path
	// We could strip out the base part, but that would not be very portable.
	if filepath.IsAbs(name) {
		return os.ErrNotExist
	}

	return nil
}

func (b *BasePathFs) Chtimes(name string, atime, mtime time.Time) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "chtimes", Path: name, Err: err}
	}
	return b.source.Chtimes(name, atime, mtime)
}

func (b *BasePathFs) Chmod(name string, mode os.FileMode) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "chmod", Path: name, Err: err}
	}
	return b.source.Chmod(name, mode)
}

func (b *BasePathFs) Name() string {
	return "BasePathFs"
}

func (b *BasePathFs) Stat(name string) (fi os.FileInfo, err error) {
	if name, err = b.RealPath(name); err != nil {
		return nil, &os.PathError{Op: "stat", Path: name, Err: err}
	}
	return b.source.Stat(name)
}

func (b *BasePathFs) Rename(oldname, newname string) (err error) {
	if oldname, err = b.RealPath(oldname); err != nil {
		return &os.PathError{Op: "rename", Path: oldname, Err: err}
	}
	if newname, err = b.RealPath(newname); err != nil {
		return &os.PathError{Op: "rename", Path: newname, Err: err}
	}
	return b.source.Rename(oldname, newname)
}

func (b *BasePathFs) RemoveAll(name string) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "remove_all", Path: name, Err: err}
	}
	return b.source.RemoveAll(name)
}

func (b *BasePathFs) Remove(name string) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "remove", Path: name, Err: err}
	}
	return b.source.Remove(name)
}

func (b *BasePathFs) OpenFile(name string, flag int, mode os.FileMode) (f File, err error) {
	if name, err = b.RealPath(name); err != nil {
		return nil, &os.PathError{Op: "openfile", Path: name, Err: err}
	}
	sourcef, err := b.source.OpenFile(name, flag, mode)
	if err != nil {
		return nil, err
	}
	return &BasePathFile{sourcef, b.path}, nil
}

func (b *BasePathFs) Open(name string) (f File, err error) {
	if name, err = b.RealPath(name); err != nil {
		return nil, &os.PathError{Op: "open", Path: name, Err: err}
	}
	sourcef, err := b.source.Open(name)
	if err != nil {
		return nil, err
	}
	return &BasePathFile{File: sourcef, path: b.path}, nil
}

func (b *BasePathFs) Mkdir(name string, mode os.FileMode) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "mkdir", Path: name, Err: err}
	}
	return b.source.Mkdir(name, mode)
}

func (b *BasePathFs) MkdirAll(name string, mode os.FileMode) (err error) {
	if name, err = b.RealPath(name); err != nil {
		return &os.PathError{Op: "mkdir", Path: name, Err: err}
	}
	return b.source.MkdirAll(name, mode)
}

func (b *BasePathFs) Create(name string) (f File, err error) {
	if name, err = b.RealPath(name); err != nil {
		return nil, &os.PathError{Op: "create", Path: name, Err: err}
	}
	sourcef, err := b.source.Create(name)
	if err != nil {
		return nil, err
	}
	return &BasePathFile{File: sourcef, path: b.path}, nil
}

func (b *BasePathFs) LstatIfPossible(name string) (os.FileInfo, bool, error) {
	name, err := b.RealPath(name)
	if err != nil {
		return nil, false, &os.PathError{Op: "lstat", Path: name, Err: err}
	}
	if lstater, ok := b.source.(Lstater); ok {
		return lstater.LstatIfPossible(name)
	}
	fi, err := b.source.Stat(name)
	return fi, false, err
}

// vim: ts=4 sw=4 noexpandtab nolist syn=go