[PATCH] http: support CURLPROXY_HTTPS

[Wei Shuyu <wsy@dogben.com>]

HTTP proxy over SSL is supported by curl since 7.52.0.
This is very useful for networks with protocol whitelist.

Signed-off-by: Wei Shuyu <wsy@dogben.com>
---
 http.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/http.c b/http.c
index 215bebef1..32d33261c 100644
--- a/http.c
+++ b/http.c
@@ -865,6 +865,11 @@ static CURL *get_curl_handle(void)
 		else if (starts_with(curl_http_proxy, "socks"))
 			curl_easy_setopt(result,
 				CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
+#endif
+#if LIBCURL_VERSION_NUM >= 0x073400
+		else if (starts_with(curl_http_proxy, "https"))
+			curl_easy_setopt(result,
+				CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
 #endif
 		if (strstr(curl_http_proxy, "://"))
 			credential_from_url(&proxy_auth, curl_http_proxy);
-- 
2.15.1