Re: [PATCH] Handle DT_UNKNOWN in gconv-modules.d

[Siddhesh Poyarekar <siddhesh@sourceware.org>]

On 6/9/21 10:51 PM, Adhemerval Zanella wrote:
> 
> 
> On 09/06/2021 01:38, Siddhesh Poyarekar via Libc-alpha wrote:
>> On filesystems that do not support dt_type, a regular file shows up as
>> DT_UNKNOWN.  Fall back to using lstat64 to read file properties in
>> such cases.
> 
> The patch looks ok, but two things raised checking on this code: 1.
> the code is essentially the same on both places and 2. the use of
> alloca() even when it is assured that is bounded and 2.
> 
> The former would be nice if could consolidate it (even by adding
> a file where both iconvconfig and iconv could include or even
> by a GLIBC_PRIVATE symbol), but it is not a deal breaker.

I tried to do this but the code came out clumsier because the result 
(call to handle_file vs read_conf_file) have different semantics.

> But I think we should move away from alloca, even when we know it
> is bounded (sorry if I didn't catch on the previous patch).  For
> this specific usage we can use asprintf to create the path or use
> a static PATH_MAX buffer.

I agree, a static PATH_MAX makes sense, I'll do that.

Thanks,
Siddhesh