[lwip-devel] [bug #46289] tcp_write fails with ERR_MEM if TCP_SND_QUEUELEN is reached

[Ambroz Bizjak]

Follow-up Comment #2, bug #46289 (project lwip):

Hey,
I think it can be done that way. But, I'm a bit afraid that this would make
the two functions very tightly coupled, and one could change the tcp_write()
logic while forgetting to make the appropriate change in the
tcp_write_partly() calculating the available space, breaking it.

So I have a counter-proposal. We make the partial writes an optional feature
enabled with e.g. LWIP_TCP_PARTIAL_WRITE. With partial writes disabled, the
pretty much stays as it is right now, so just a tcp_write() function. With
partial writes enabled, the current tcp_write() code actually becomes the new
tcp_write_partly(), which works the same as my tcp_write_ext() (flag enabled
partial mode). And in this case we also have a tcp_write() wrapper on top of
tcp_write_partly().

Finally I think I we can get away without a TCP_WRITE_FLAG_PARTIAL flag if we
just look at whether written_len is not NULL.

    _______________________________________________________

Reply to this item at:

  <http://savannah.nongnu.org/bugs/?46289>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.nongnu.org/