[Cin] Fwd: tried to make giflist, got segfault

[Phyllis Smith]

Attached is the Freelancer patch so if Andrew and Andrea ould test (and
Andrew look at the code) to see if it is usable, I would appreciate it.
(Andrea, cd to ...cinelerra-5.1/cinelerra   and do "patch < location of
downloaded patch"    should work.

On Mon, Dec 13, 2021 at 12:07 AM Andrew Randrianasulu <
randrianasulu at gmail.com> wrote:

>
>
> On Sunday, December 12, 2021, Phyllis Smith <phylsmith2017 at gmail.com>
> wrote:
>
>>
>>
>>> this patch prevent gif segfault problem (but all images become  the same
>>> for given list!) , but not sure about other, similar crashes you observed?
>>>
>> Andrew, patch works just like you stated and most importantly prevents
>> the crash.  Similar mod would have to be put into fileexr.C, filejpeg.C,
>> etc. but let me see if I can get the Freelancer to come up with a different
>> solution -- he keeps nagging me for something to do.
>>
>
> well, I think real solution should augment those filereaders with
> something like report_w, report_h and then caller must check if previous
> (cached) info remain the same for current frame.. so at first call we check
> those params and load them into var1_w, and var1_h, then set someflag
> we_read_first_info, then just copy var1_w/h to var2_w/h, repeat, now when
> we have someflag set (thus not first read) compare those two, abort reading
> of mismatched frame.
>
>
> after trying to write down it like this I even think we can name vars
> first_w, first_h and then check current fetched values against them, not
> re-loading pair for next/priv  frame at each step.
> this is for avoiding  quite expensive decoding, if I understand our code
> correctly!
>
> good luck to freelancer, good health to both of you...
>
>>
>> I agree that it needs a safeguard.  Let me know if you do not find a
>>>> solution because a freelancer wants to work on something and I thought he
>>>> might be able to actually do this.  Most of the problems are way too
>>>> difficult for someone not familiar with Cinelerra to even attempt to work
>>>> on.
>>>>
>>>
>>
>
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