Re: [Qemu-devel] [PATCH] block/curl: Implement the libcurl timer callback interface

[Paolo Bonzini <pbonzini@redhat.com>]

Il 16/01/2014 10:55, Peter Maydell ha scritto:
> On 16 January 2014 08:38, Paolo Bonzini <pbonzini@redhat.com> wrote:
>> Il 15/01/2014 23:15, Peter Maydell ha scritto:
>>>
>>>>> +    curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
>>> The libcurl docs say "This function was added in libcurl 7.15.4, and
>>>  is deemed stable since 7.16.0. " So if we want to keep supporting
>>> pre-7.16 libcurl then we need to retain the multi_socket_all codepath.
>>>
>>> On the other hand 7.16 was released in October 2006. What's
>>> the oldest version we actually care about?
>>
>> I say 7.16 :)
> 
> What dos RHEL5 ship? That's usually our benchmark for
> "oldest thing we need to support". Ubuntu 10.04 LTS (lucid)
> and Debian oldstable (squeeze) both ship something more
> recent than 7.16, so we're OK there.
> 
> We should probably update the configure test to check for
> curl_multi_socket_action() rather than curl_multi_setopt().

It ships 7.15.5.  But curl_multi_socket_action is used only if there is
a timeouts, and curl_multi_timeout_do will never be called before
7.16.0.  Your patch calls aio_timer_init unconditionally, but the timer
will never be activated with timer_mod (which I think is a fine thing to
do).

Paolo