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Altera_Forum's avatar
Altera_Forum
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21 years ago

LWIP standalong server bug?

Hi,

Examining the example lwip_server, in particular httpd.c.

When tcp_close is called the pcb is deallocated, so surely a tcp_new,bind must be performed again?

in the LWIP source tcp.c you can see the memp_free?

is there any good documentation for the LWIP rawapi, the little rawapi.txt file does not talk about pbuf management - such as is done within http_recv() for example?

is the pbuf_free() necessary? and should the tcp_recved(pcb, p->tot_len) not actually be tcp_recved(pcb,p->len) ? tot_len is the sze of the buffer and all other chained ones? (or so the LWIP source comments say?)

Are there any other examples of LWIP rawapi apps?

Thanks!

http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/huh.gif

Thanks!

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    21 years ago

    I&#39;m also trying to use the standalone LwIP Raw API in a more extensive application than the http-server example.

    I share the complaint that you made : the &#39;rawapi.txt &#39; documentation is far from complete.

    But to be maybe of a little help to you : the thesis written by Adam Dunkels (the original designer of LwIP) is available on the internet. in Chapter 4 it discusses in general how the TCP/IP stack works and you can find some more details about memory management and the use of the pbufs.

    You can find the thesis at

    http://www.sics.se/~adam/thesis.pdf (http://www.sics.se/~adam/thesis.pdf)

    I hope this answers some questions...