Re: [PATCH 1/2] Fixes _is_git

[Chris Packham <judge.packham@gmail.com>]

On Wed, Feb 4, 2015 at 4:52 AM, Rémi Rampin <remirampin@gmail.com> wrote:
> 2015-02-02 12:24 UTC-05:00, Remi Rampin <remirampin@gmail.com>:
>>>  proc _is_git {path} {
>>> +       if {[file isfile $path]} {
>>> +               set fp [open $path r]
>>> +               gets $fp line
>>> +               close $fp
>>> +               if {[regexp "^gitdir: (.+)$" $line line link_target]} {
>
> 2015-02-03 3:44 UTC-05:00, Chris Packham <judge.packham@gmail.com>:
>> It might be simpler to use one of the 'string' commands e.g. string
>> wordend "gitdir: " I also suspect the string functions would be faster
>> than regexp but that probably doesn't matter.
>
> I want to check that the file actually begins with "gitdir: " and then
> extract the path, so I'm not sure if using string functions is that
> simple/fast.

Makes sense.

>
>>> +                       return [_is_git [file join [file dirname $path] $link_target]]
>
>> Do we want to avoid pathological cases of infinite recursion? Someone
>> would have to maliciously create such a situation.
>
> Limiting the recursion is very simple, but I'm not sure people are
> supposed to stumble on that. More importantly this probably calls for a
> different error message, thus a new error result that I am not ready to
> implement. But it could be another patch.
> But I suppose I can add a simple "return 0" limit to the recursion if
> needed, let me know.

It'd have to be fairly intentional to cause any real problems. The one
thing I was thinking was to factor out the part that checks for HEAD
info objects etc into a __is_git that _is_git could call thus
eliminating recursion but I don't see it really being anything more
than a theoretical issue.