Re: [PATCH v9 5/5] transport: add from_user parameter to is_transport_allowed

> On Wed, Dec 14, 2016 at 12:37:52PM -0800, Brandon Williams wrote:
> 
> > Naively looking at the code (and your longer suggestion), is there a
> > reason why we couldn't simply have http-walker set CURLOPT_PROTOCOLS
> > with get_curl_allowed_protocols(0) in the fetch_alternates() function?
> > That way we just override the CURLOPT_PROTOCOLS value when alternates
> > are involved.
> 
> No, because we may have many curl handles (especially for the
> http-walker, which wants to fetch several objects simultaneously), and
> they get recycled as needed for many requests.
> 
> So setting a restriction there on slot->curl will only cover the one
> handle, and miss other ones which may be used later (and likewise, that
> one handle with the restriction may get recycled and used for a
> non-alternate fetch, and would be unnecessarily restrictive).
> 
> That's why any curl-level settings have to happen when we call
> get_active_slot(), since that's when we know what we're actually using
> the handle for.