1// Copyright 2009 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
5package os
6
7import (
8	"internal/filepathlite"
9	"syscall"
10)
11
12// MkdirAll creates a directory named path,
13// along with any necessary parents, and returns nil,
14// or else returns an error.
15// The permission bits perm (before umask) are used for all
16// directories that MkdirAll creates.
17// If path is already a directory, MkdirAll does nothing
18// and returns nil.
19func MkdirAll(path string, perm FileMode) error {
20	// Fast path: if we can tell whether path is a directory or file, stop with success or error.
21	dir, err := Stat(path)
22	if err == nil {
23		if dir.IsDir() {
24			return nil
25		}
26		return &PathError{Op: "mkdir", Path: path, Err: syscall.ENOTDIR}
27	}
28
29	// Slow path: make sure parent exists and then call Mkdir for path.
30
31	// Extract the parent folder from path by first removing any trailing
32	// path separator and then scanning backward until finding a path
33	// separator or reaching the beginning of the string.
34	i := len(path) - 1
35	for i >= 0 && IsPathSeparator(path[i]) {
36		i--
37	}
38	for i >= 0 && !IsPathSeparator(path[i]) {
39		i--
40	}
41	if i < 0 {
42		i = 0
43	}
44
45	// If there is a parent directory, and it is not the volume name,
46	// recurse to ensure parent directory exists.
47	if parent := path[:i]; len(parent) > len(filepathlite.VolumeName(path)) {
48		err = MkdirAll(parent, perm)
49		if err != nil {
50			return err
51		}
52	}
53
54	// Parent now exists; invoke Mkdir and use its result.
55	err = Mkdir(path, perm)
56	if err != nil {
57		// Handle arguments like "foo/." by
58		// double-checking that directory doesn't exist.
59		dir, err1 := Lstat(path)
60		if err1 == nil && dir.IsDir() {
61			return nil
62		}
63		return err
64	}
65	return nil
66}
67
68// RemoveAll removes path and any children it contains.
69// It removes everything it can but returns the first error
70// it encounters. If the path does not exist, RemoveAll
71// returns nil (no error).
72// If there is an error, it will be of type [*PathError].
73func RemoveAll(path string) error {
74	return removeAll(path)
75}
76
77// endsWithDot reports whether the final component of path is ".".
78func endsWithDot(path string) bool {
79	if path == "." {
80		return true
81	}
82	if len(path) >= 2 && path[len(path)-1] == '.' && IsPathSeparator(path[len(path)-2]) {
83		return true
84	}
85	return false
86}
87