SNI: reuse selected configuration for all requests in a connection. Previously, only the first request in a connection was assigned the configuration selected by SNI. All subsequent requests initially used the default server's configuration, ignoring SNI, which was wrong. Now all subsequent requests in a connection will initially use the configuration selected by SNI. This is done by storing a pointer to configuration in http connection object. It points to default server's configuration initially, but changed upon receipt of SNI. (The request's configuration can be further refined when parsing the request line and Host: header.) This change was not made specific to SNI as it also allows slightly faster access to configuration without the request object.

scgi_param  REQUEST_METHOD     $request_method;
scgi_param  REQUEST_URI        $request_uri;
scgi_param  QUERY_STRING       $query_string;
scgi_param  CONTENT_TYPE       $content_type;

scgi_param  DOCUMENT_URI       $document_uri;
scgi_param  DOCUMENT_ROOT      $document_root;
scgi_param  SCGI               1;
scgi_param  SERVER_PROTOCOL    $server_protocol;
scgi_param  HTTPS              $https if_not_empty;

scgi_param  REMOTE_ADDR        $remote_addr;
scgi_param  REMOTE_PORT        $remote_port;
scgi_param  SERVER_PORT        $server_port;
scgi_param  SERVER_NAME        $server_name;