Venkat Akella found out that libcurl did not like HTTP responses that simply

responded with a single status line and no headers nor body. Starting now, a
HTTP response on a persistent connection (i.e not set to be closed after the
response has been taken care of) must have Content-Length or chunked
encoding set, or libcurl will simply assume that there is no body.

To my horror I learned that we had no less than 57(!) test cases that did bad
HTTP responses like this, and even the test http server (sws) responded badly
when queried by the test system if it is the test system. So although the
actual fix for the problem was tiny, going through all the newly failing test
cases got really painful and boring.

lib/transfer.c

@@ -501,9 +501,19 @@ CURLcode Curl_readwrite(struct connectdata *conn,
                   k->keepon |= KEEP_WRITE;
                 }
               }
-              else
+              else {
                 k->header = FALSE; /* no more header to parse! */
 
+                if((k->size == -1) && !conn->bits.chunk && !conn->bits.close)
+                  /* When connection is not to get closed, but no
+                     Content-Length nor Content-Encoding chunked have been
+                     received, there is no body in this response. We don't set
+                     stop_reading TRUE since that would also prevent necessary
+                     authentication actions to take place. */
+                  conn->bits.no_body = TRUE;
+
+              }
+
               if (417 == k->httpcode) {
                 /*
                  * we got: "417 Expectation Failed" this means: