| // Copyright 2020 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 cache |
| |
| import ( |
| "fmt" |
| "path/filepath" |
| "syscall" |
| ) |
| |
| func init() { |
| checkPathCase = windowsCheckPathCase |
| } |
| |
| func windowsCheckPathCase(path string) error { |
| // Back in the day, Windows used to have short and long filenames, and |
| // it still supports those APIs. GetLongPathName gets the real case for a |
| // path, so we can use it here. Inspired by |
| // http://stackoverflow.com/q/2113822. |
| |
| // Short paths can be longer than long paths, and unicode, so be generous. |
| buflen := 4 * len(path) |
| namep, err := syscall.UTF16PtrFromString(path) |
| if err != nil { |
| return err |
| } |
| short := make([]uint16, buflen) |
| n, err := syscall.GetShortPathName(namep, &short[0], uint32(len(short)*2)) // buflen is in bytes. |
| if err != nil { |
| return err |
| } |
| if int(n) > len(short)*2 { |
| return fmt.Errorf("short buffer too short: %v vs %v*2", n, len(short)) |
| } |
| long := make([]uint16, buflen) |
| n, err = syscall.GetLongPathName(&short[0], &long[0], uint32(len(long)*2)) |
| if err != nil { |
| return err |
| } |
| if int(n) > len(long)*2 { |
| return fmt.Errorf("long buffer too short: %v vs %v*2", n, len(long)) |
| } |
| longstr := syscall.UTF16ToString(long) |
| |
| isRoot := func(p string) bool { |
| return p[len(p)-1] == filepath.Separator |
| } |
| for got, want := path, longstr; !isRoot(got) && !isRoot(want); got, want = filepath.Dir(got), filepath.Dir(want) { |
| if g, w := filepath.Base(got), filepath.Base(want); g != w { |
| return fmt.Errorf("case mismatch in path %q: component %q is listed by Windows as %q", path, g, w) |
| } |
| } |
| return nil |
| } |