Re: [Qemu-devel] [Qemu-trivial] [PATCH] curl: Don't set curl options on the handle just before it's going to be deleted.

[Richard W.M. Jones]

On Mon, Jun 10, 2013 at 07:34:52PM +0400, Michael Tokarev wrote:
> 10.06.2013 17:19, Richard W.M. Jones wrote:
> > From: "Richard W.M. Jones" <address@hidden>
> > 
> > (Found by Kamil Dudka)
> > 
> > Signed-off-by: Richard W.M. Jones <address@hidden>
> > ---
> >  block/curl.c | 1 -
> >  1 file changed, 1 deletion(-)
> > 
> > diff --git a/block/curl.c b/block/curl.c
> > index b634ccf..bf31efe 100644
> > --- a/block/curl.c
> > +++ b/block/curl.c
> > @@ -453,7 +453,6 @@ static int curl_open(BlockDriverState *bs, QDict 
> > *options, int flags)
> >          goto out;
> >      curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
> >      curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void 
> > *)curl_read_cb);
> > -    curl_easy_setopt(state->curl, CURLOPT_NOBODY, 0);
> >      if (d)
> >          s->len = (size_t)d;
> >      else if(!s->len)
> 
> Adding a bit more context:
> 
> 
>     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
>     curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void 
> *)curl_size_cb);
>     if (curl_easy_perform(state->curl))
>         goto out;
>     curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
>     curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void 
> *)curl_read_cb);
> =>> curl_easy_setopt(state->curl, CURLOPT_NOBODY, 0);
>     if (d)
>         s->len = (size_t)d;
>     else if(!s->len)
>         goto out;
>     DPRINTF("CURL: Size = %zd\n", s->len);
> 
>     curl_clean_state(state);
>     curl_easy_cleanup(state->curl);
>     state->curl = NULL;
> 
> So indeed, the curl object is being removed here a few lines down the code.
> 
> But it looks like the previous call to curl_easy_setopt, to set WRITEFUNCTION,
> is also not very useful. Should we probably want to remove that too, or don't
> remove either of these?

Yes you're right.  For some reason I "saw" another call to
curl_easy_perform which obviously isn't there in reality.  Will send a
v2 patch shortly after I've done a bit of testing.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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