code review 5683072: godoc: fix potential index out-of-bounds error

godoc: fix potential index out-of-bounds error

[gri, 2012-02-22 06:43:56]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[bradfitz, 2012-02-22 06:47:24]

LGTM

On Wed, Feb 22, 2012 at 5:43 PM, <gri@golang.org> wrote:

> Reviewers: golang-dev_googlegroups.com,
>
> Message:
> Hello golang-dev@googlegroups.com,
>
> I'd like you to review this change to
> https://go.googlecode.com/hg/
>
>
> Description:
> godoc: fix potential index out-of-bounds error
>
> Please review this at
http://codereview.appspot.com/**5683072/<http://codereview.appspot.com/5683072/>
>
> Affected files:
>  M src/cmd/godoc/mapping.go
>
>
> Index: src/cmd/godoc/mapping.go
> ==============================**==============================**=======
> --- a/src/cmd/godoc/mapping.go
> +++ b/src/cmd/godoc/mapping.go
> @@ -139,6 +139,8 @@
>        }
>  }
>
> +const sep = string(filepath.Separator)
> +
>  // splitFirst splits a path at the first path separator and returns
>  // the path's head (the top-most directory specified by the path) and
>  // its tail (the rest of the path). If there is no path separator,
> @@ -146,7 +148,7 @@
>  // Specifically, splitFirst("foo") == splitFirst("foo/").
>  //
>  func splitFirst(path string) (head, tail string) {
> -       if i := strings.Index(path, string(filepath.Separator)); i > 0 {
> +       if i := strings.Index(path, sep); i > 0 {
>                // 0 < i < len(path)
>                return path[0:i], path[i+1:]
>        }
> @@ -179,7 +181,7 @@
>  func (m *Mapping) ToRelative(fpath string) string {
>        for _, e := range m.list {
>                // if fpath has prefix e.path, the next character must be a
> separator (was issue 3096)
> -               if strings.HasPrefix(fpath, e.path) && fpath[len(e.path)]
> == filepath.Separator {
> +               if strings.HasPrefix(fpath, e.path+sep) {
>                        spath := filepath.ToSlash(fpath)
>                        // /absolute/prefix/foo -> prefix/foo
>                        return path.Join(e.prefix, spath[len(e.path):]) //
> Join will remove a trailing '/'
>
>
>

[dsymonds, 2012-02-22 06:49:43]

LGTM

[gri, 2012-02-22 06:50:02]

*** Submitted as http://code.google.com/p/go/source/detail?r=19b7572f50e3 ***

godoc: fix potential index out-of-bounds error

R=golang-dev, bradfitz, dsymonds
CC=golang-dev
http://codereview.appspot.com/5683072