url: Add option CURLOPT_HAPPY_EYEBALLS_TIMEOUT

- Add new option CURLOPT_HAPPY_EYEBALLS_TIMEOUT to set libcurl's happy
  eyeball timeout value.

- Add new optval macro CURL_HET_DEFAULT to represent the default happy
  eyeballs timeout value (currently 200 ms).

- Add new tool option --happy-eyeballs-timeout-ms to expose
  CURLOPT_HAPPY_EYEBALLS_TIMEOUT. The -ms suffix is used because the
  other -timeout options in the tool expect seconds not milliseconds.

Closes https://github.com/curl/curl/pull/2260

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/connect.c b/lib/connect.c
index c3add43cc..1a27ae135 100644
--- a/lib/connect.c
+++ b/lib/connect.c
@@ -783,7 +783,8 @@ CURLcode Curl_is_connected(struct connectdata *conn,
 
       /* should we try another protocol family? */
       if(i == 0 && conn->tempaddr[1] == NULL &&
-         Curl_timediff(now, conn->connecttime) >= HAPPY_EYEBALLS_TIMEOUT) {
+         (Curl_timediff(now, conn->connecttime) >=
+          data->set.happy_eyeballs_timeout)) {
         trynextip(conn, sockindex, 1);
       }
     }
@@ -1206,7 +1207,8 @@ CURLcode Curl_connecthost(struct connectdata *conn,  /* context */
   }
 
   data->info.numconnects++; /* to track the number of connections made */
-  Curl_expire(conn->data, HAPPY_EYEBALLS_TIMEOUT, EXPIRE_HAPPY_EYEBALLS);
+  Curl_expire(conn->data, data->set.happy_eyeballs_timeout,
+              EXPIRE_HAPPY_EYEBALLS);
 
   return CURLE_OK;
 }