Re: [lwip-users] Re: Assertion : "tcp_enqueue: no pbufs on queue => both queues empty"

[Jonathan Larmour]

Kelvin Lawson wrote:
> > I use lwip in a embedded system, one time I have got this the 
> > following message:
> > "tcp_enqueue: no pbufs on queue => both queues empty"
> > Exactly on this line:
> > LWIP_ASSERT("tcp_enqueue: no pbufs on queue => both queues empty",
> >       pcb->unacked == NULL && pcb->unsent == NULL);
>
> I had this problem recently, and it was down to my setting for 
> TCP_SND_QUEUELEN. This must be less than 256, because the data type used 
> for storing the queue length (snd_queuelen) is 8 bits. Any larger and 
> the snd_queuelen counter will overflow.

Any developer care to make the obvious quick change? It's probably more 
effort overall for a developer if I submitted a patch rather than to just 
to do it:
#if (TCP_SND_QUEUELEN > 255)
  u16_t
#else
  u8_t
#endif
  snd_queuelen; /* Available buffer space for sending (in tcp_segs). */

and ditto for queuelen in tcp_enqueue() in tcp_out.c.

But if you prefer I can submit this as a patch.

Jifl
--
eCosCentric    http://www.eCosCentric.com/    The eCos and RedBoot experts
------["The best things in life aren't things."]------      Opinions==mine