gRPC: disabled keepalive when sending control frames was blocked. If sending request body was not completed (u->request_body_sent is not set), the upstream keepalive module won't save such a connection. However, it is theoretically possible (though highly unlikely) that sending of some control frames can be blocked after the request body was sent. The ctx->output_blocked flag introduced to disable keepalive in such cases.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


cat << END >> $NGX_AUTO_HEADERS_H

#ifndef $have
#define $have  1
#endif

END