On Mon, 29 Sep 2008, Vlad Grachov wrote:

Thanks! But I do have a few comments on this:

First, please give us at least a week to respond until you resend the same
stuff. You can check http://curl.haxx.se/lxr/source/TODO-RELEASE to figure out
if your issue is added for pending "action".

Then, you post libcurl stuff to the users list which we generally
discourage since you cut out the vast majority of libcurl hackers that hang
out on the correct list: curl-library

Thirdly, your patch to libssh2 should be posted to the libssh2 list for
consideration for that project. I would also suggest that you add a man page
for the new function, to make it easier to the libssh2 crowd to understand the
function and how to use it.

> The problem is related to libssh2 as well because LIBSSH2_ERROR_EAGAIN
> return code does not provide any information about the cause of would-block.
> Regardless of whether recv() or send() returned EAGAIN all the information
> curl can get from libssh2 is the one and same LIBSSH2_ERROR_EAGAIN error
> code.
>
> The proposed 2 patches are a patch to libssh2 and a patch to curl. They
> modify the libraries in a minor way.

Since this libcurl patch makes libcurl depend on this change in libssh2 it
would also make sense to do a "best effort" for the cases where the libssh2 is
not up-to-date with this. That is, #ifdefed on
HAVE_LIBSSH2_SESSION_BLOCK_DIRECTION.

But also, I would rather change the libssh2 function's meaning to instead be
"I want you to wait for these actions on the socket before you call the
libssh2 function again" since that would then allow libssh2 to actually wait
for multiple actions without the API having to be changed again. The function
would then return 1 or 2 bits set in a bitmask.

The libcurl part of the patch would then also need to be modified accordingly.

> The patched curl no longer waste CPU when the socket would block. Tested
> under Linux and Windows.

That's indeed very nice to see!

-- 
  / daniel.haxx.se
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