Re: [PATCH v2 1/8] fast-import: tighten path unquoting

From: Thalia Archibald <thalia@archibald.dev>
Date: Apr 10, 2024, 08:44 UTC
Message-ID: <784B5318-F155-4D93-8085-62ACA63432E5@archibald.dev>
In-Reply-To: <CAPx1GvfgC46n_5fk3dHxg7dn393UVMi0CtHKqQ_GAaqnV_ECCQ@mail.gmail.com>

On Apr 10, 2024, at 01:18, Chris Torek <chris.torek@gmail.com> wrote:

Show 19 quoted lines

> On Tue, Apr 9, 2024 at 11:30 PM Patrick Steinhardt <ps@pks.im> wrote:
>>> +             if (include_spaces)
>>> +                     *endp = p + strlen(p);
>>> +             else
>>> +                     *endp = strchr(p, ' ');
>>> +             strbuf_add(sb, p, *endp - p);
>> 
>> strchr(3P) may return a NULL pointer in case there is no space, which
>> would make us segfault here when dereferencing `*endp`. We should
>> probably add a testcase that would hit this edge case.
> 
> Note that you can do:
> 
>    *endp = p + strcspn(p, " ");
> 
> (though `strcspn` is a fundamentally harder operation since it
> takes a string argument). Everything depends on whether you
> want to test for an explicit "there was no space at all" case of
> course; performance considerations are secondary.

I thought strchr returned a pointer to the terminating NUL byte if the needle was not found. Turns out it does return NULL in that case, as you say. strchrnul does what I want here and I’ve replaced it with that.

I’ve added a test covering this case.

Thalia