nginx with custom modules crashes in gzip crc32()

[agentzh]

On Wed, Oct 19, 2011 at 8:20 AM, artemg <nginx-forum at nginx.us> wrote:
> 0-0-400, or even 0-0-0 chain, and data can be added in next chain. I am
> doing buffering to match some patterns. In fact of this I see in error
> log:
>
> [alert] 31974#0: *98657 zero size buf in writer t:1 r:1 f:0
> 0000000001714FE0 0000000001F8D290-0000000001F8D290 0000000000000000 0-0
> while sending to client
>
> Is that ok, to have zero size bufs, or I need to modify the chain, not
> to pass them forward to other modules?
>

Passing zero-size non-special bufs to the downstream output filters is
surely BAD. You have to fix it :)

Also, using tools like valgrind's memcheck to find memory issues in
your modules is highly recommended and can often save you huge number
of hours of debugging :)

Regards,
-agentzh