ext/curl: Add CURLINFO_{USED_PROXY,HTTPAUTH_USED,PROXYAUTH_USED}

[Ayesh]

Adds support for curl_getinfo() info keys and additional array keys:

• CURLINFO_USED_PROXY - libcurl >= 8.7.9 - Zero if no proxy was used in the previous transfer or a non-zero value if a proxy was used.
• CURLINFO_HTTPAUTH_USED - libcurl >= 8.7.9 - Bitmask indicating the authentication method that was used in the previous HTTP request.
• CURLINFO_PROXYAUTH_USED - libcurl >= 8.12.0 - Bitmask indicating the authentication method that was used in the previous request done over an HTTP proxy.

curl_getinfo($ch);

[
	// ...
	"used_proxy" => 0,
	"httpauth_used" => 0,
	"proxyauth_used" => 0,
]

Because the built-in server ext/curl tests use does not support HTTP authentication, there is an online test that uses httpbin. It will be skipped by default unless online tests are run.

[devnexen]

Code wise it s very much correct, not entirely sure however how others will think of the online test.

[Ayesh]

Thank you @devnexen - I couldn't think of a way to test it with a local server. That said, we don't seem to be testing a lot of proxy/auth related features, nor any of the HTTP/2, HTTP/3, DoH, etc features either, so the online test is understandably a bit out of place.

If it makes more sense, I can remove the online test.

[cmb69]

Can we use Caddy instead of the online test? Caddy was introduced via #10669, and is used for a couple of tests (some jobs are actually running that).

[Ayesh]

Thank you @cmb69. I pushed removing httpbin, and with a new /http-basic-auth Caddy route with HTTP basic auth. I tested it locally with the same Caddyfile, but GH-Actions run will get skipped because the Curl version is older than 8.12.0.

[cmb69]

[…] but GH-Actions run will get skipped because the Curl version is older than 8.12.0.

It would be good to also have a job using recent cURL; possibly on Windows, since we're rather up to date there (at least for the master branch), but this is a separate issue.

Please see my comment below; I guess that should solve the Windows CI failure.

[cmb69]

Thank you!