Re: [RFC] globmatch() helper function
From: Steven Rostedt
Date: Wed Dec 17 2008 - 11:22:50 EST
On Wed, 2008-12-17 at 11:04 -0500, George Spelvin wrote:
>
> The problem is, what if some future thoughtless person feeds user data
> into the pattern argument?
>
> I could just take support for non-trailing * out entirely. That would be
> a different sort of documentation burden.
>
> Or I could just add an explicit 2-level stack. If you overflow the stack,
> matching always fails. Unfortunately, the code will be larger.
>
> Do people think that would be, on balance, better? It would be plenty
> good enough for the blacklist application.
Having a static function do the work and pass in a "depth" parameter
should be sufficient. As Andi mentioned, a depth of 10 should be plenty.
Like this:
static bool
globmatch_internal(const char *pat, const char *str, int depth)
{
if (depth > 10)
return false;
[...]
while (!globmatch_internal(pat+1, str, depth+1))
[...]
}
bool globmatch(const char *pat, const char *str)
{
return globmatch_internal(pat, str, 0);
}
Make sure you include a "Signed-off-by:" as well.
-- Steve
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