CONNECT: Revert Curl_proxyCONNECT back to 7.29.0 design

This reverts commit cb3e6dfa3511 and instead fixes the problem
differently.

The reverted commit addressed a test failure in test 1021 by simplifying
and generalizing the code flow in a way that damaged the
performance. Now we modify the flow so that Curl_proxyCONNECT() again
does as much as possible in one go, yet still do test 1021 with and
without valgrind. It failed due to mistakes in the multi state machine.

Bug: http://curl.haxx.se/bug/view.cgi?id=1397
Reported-by: Paul Saab

1 files changed, 10 insertions, 6 deletions

diff --git a/lib/multi.c b/lib/multi.c
index ca975a056..1e5b3c8df 100644
--- a/lib/multi.c
+++ b/lib/multi.c
@@ -1137,11 +1137,7 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi,
       data->result = Curl_http_connect(data->easy_conn, &protocol_connect);
 
       if(data->easy_conn->bits.proxy_connect_closed) {
-        /* reset the error buffer */
-        if(data->set.errorbuffer)
-          data->set.errorbuffer[0] = '\0';
-        data->state.errorbuf = FALSE;
-
+        /* connect back to proxy again */
         data->result = CURLE_OK;
         result = CURLM_CALL_MULTI_PERFORM;
         multistate(data, CURLM_STATE_CONNECT);
@@ -1167,7 +1163,15 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi,
                                                &protocol_connect);
       }
 
-      if(CURLE_OK != data->result) {
+      if(data->easy_conn->bits.proxy_connect_closed) {
+        /* connect back to proxy again since it was closed in a proxy CONNECT
+           setup */
+        data->result = CURLE_OK;
+        result = CURLM_CALL_MULTI_PERFORM;
+        multistate(data, CURLM_STATE_CONNECT);
+        break;
+      }
+      else if(CURLE_OK != data->result) {
         /* failure detected */
         /* Just break, the cleaning up is handled all in one place */
         disconnect_conn = TRUE;