# HG changeset patch
# User Valentin Bartenev <vbart@nginx.com>
# Date 1466099711 -10800
# Node ID d375f4210e412781e8086410f9054ddfacee95c2
# Parent  78533a74af1133e3b52aced2224e6564b09db514
HTTP/2: fixed the "http request count is zero" alert.

When the stream is terminated the HEADERS frame can still wait in the output
queue.  This frame can't be removed and must be sent to the client anyway,
since HTTP/2 uses stateful compression for headers.  So in order to postpone
closing and freeing memory of such stream the special close stream handler
is set to the write event.  After the HEADERS frame is sent the write event
is called and the stream will be finally closed.

Some events like receiving a RST_STREAM can trigger the read handler of such
stream in closing state and cause unexpected processing that can result in
another attempt to finalize the request.  To prevent it the read handler is
now set to ngx_http_empty_handler.

Thanks to Amazon.

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
@@ -3935,6 +3935,7 @@ ngx_http_v2_close_stream(ngx_http_v2_str
 
     if (stream->queued) {
         fc->write->handler = ngx_http_v2_close_stream_handler;
+        fc->read->handler = ngx_http_empty_handler;
         return;
     }