QUIC: added support for segmentation offloading. To improve output performance, UDP segmentation offloading is used if available. If there is a significant amount of data in an output queue and path is verified, QUIC packets are not sent one-by-one, but instead are collected in a buffer, which is then passed to kernel in a single sendmsg call, using UDP GSO. Such method greatly decreases number of system calls and thus system load.

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


    cat << END                                            >> $NGX_MAKEFILE

$NGX_LIBATOMIC/src/libatomic_ops.a:	$NGX_LIBATOMIC/Makefile
	cd $NGX_LIBATOMIC && \$(MAKE)

$NGX_LIBATOMIC/Makefile:	$NGX_MAKEFILE
	cd $NGX_LIBATOMIC \\
	&& if [ -f Makefile ]; then \$(MAKE) distclean; fi \\
	&& ./configure

END