Re: [lwip-users] Choosing the right lwip API...

[Jonathan Larmour]

DownyTif wrote:
> I do have some more questions on this topic... I decided to test the speed
> improvements using the RAW API. This API allows me to use only one thread to
> do whatever I want instead of two threads using the sequential API because
> the "recv" is blocking and I need to send data in the idle time.
>
> 1- I just read from the Wiki that the RAW API can only be used by the main
> thread?? In my project, I need the main thread to call
> "vTaskStartScheduler()" to run FreeRTOS for multithreading, which never
> returns. So, I can't use my main thread to manage the RAW API, but I can
> call "tcp_new", "tcp_bind", "tcp_listen" and "tcp_accept" before. Is that
> sufficient?

It just means a single thread. It doesn't have to be the thread used for 
main(). What really matters is that nothing can call into lwIP core code 
from more than one context at the same time, whether it be another thread, 
interrupt handler, etc.

> 2- 
> What do I need to call to use/init the RAW API? For the sequential, I was
> using sys_init(), mem_init(), memp_init(), pbuf_init(), netif_init(),
> tcpip_init(EthernetConfigInterface, NULL). I'm not sure if I still need
> those... or if I'm missing something.

What version of lwIP are you using? For 1.3.0, you can use lwip_init() 
instead for much of it, except for tcpip_init (which is specific to when 
using the sequential or sockets APIs). See src/core/init.c. I would have 
hoped it would be in the wiki, but from a look around I'm not sure it's 
there yet.

Actually it should also be described in doc/rawapi.txt in the source 
distribution. Patches welcome from anyone who's tried it recently!

> 3-
> I haven't found it, so I think it would be good to have a little resume of
> what are the #defines needed by all the API. For example, if I want to use
> the RAW API, I must absolutly define some values in the lwipopts.h file.
> Personally, I'm not sure I have everything configured ok..

Most of the defines are still relevant when using the raw API. And the 
ones that aren't relevant are ignored. After all, the sequential API is 
essentially just a user of the raw API itself.

Jifl
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