http: support file handles for HTTP_KEEP_ERROR

HTTP_KEEP_ERROR makes it easy to debug HTTP transport errors. In order
to make HTTP_KEEP_ERROR enabled for all requests, file handles need to
be supported.

Signed-off-by: Masaya Suzuki <masayasuzuki@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/http.c b/http.c
index eacc2a75ef2e41da9d5f5741defcf1952e6c01a3..ab4279a1ca6062576a294faac41f756d30e99b20 100644 (file)
--- a/http.c
+++ b/http.c
@@ -1952,16 +1952,26 @@ static int http_request_reauth(const char *url,
        /*
         * If we are using KEEP_ERROR, the previous request may have
         * put cruft into our output stream; we should clear it out before
-        * making our next request. We only know how to do this for
-        * the strbuf case, but that is enough to satisfy current callers.
+        * making our next request.
         */
        if (options && options->keep_error) {
                switch (target) {
                case HTTP_REQUEST_STRBUF:
                        strbuf_reset(result);
                        break;
+               case HTTP_REQUEST_FILE:
+                       if (fflush(result)) {
+                               error_errno("unable to flush a file");
+                               return HTTP_START_FAILED;
+                       }
+                       rewind(result);
+                       if (ftruncate(fileno(result), 0) < 0) {
+                               error_errno("unable to truncate a file");
+                               return HTTP_START_FAILED;
+                       }
+                       break;
                default:
-                       BUG("HTTP_KEEP_ERROR is only supported with strbufs");
+                       BUG("Unknown http_request target");
                }
        }