[nginx] HTTP/2: write logs when refusing streams with data.

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/ab16126a06a0
branches:  
changeset: 6516:ab16126a06a0
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Mon Apr 18 21:18:24 2016 +0300
description:
HTTP/2: write logs when refusing streams with data.

Refusing streams is known to be incorrectly handled at least by IE, Edge
and Safari.  Make sure to provide appropriate logging to simplify fixing
this in the affected browsers.

diffstat:

 src/http/v2/ngx_http_v2.c |  4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diffs (14 lines):

diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c
@@ -1060,6 +1060,10 @@ ngx_http_v2_state_headers(ngx_http_v2_co
 
     if (!h2c->settings_ack && !(h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG))
     {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent stream with data "
+                      "before settings were acknowledged");
+
         status = NGX_HTTP_V2_REFUSED_STREAM;
         goto rst_stream;
     }