Upstream: fixed X-Accel-Expires/Cache-Control/Expires handling. Previously, if caching was disabled due to Expires in the past, nginx failed to cache the response even if it was cacheable as per subsequently parsed Cache-Control header (ticket #964). Similarly, if caching was disabled due to Expires in the past, "Cache-Control: no-cache" or "Cache-Control: max-age=0", caching was not used if it was cacheable as per subsequently parsed X-Accel-Expires header. Fix is to avoid disabling caching immediately after parsing Expires in the past or Cache-Control, but rather set flags which are later checked by ngx_http_upstream_process_headers() (and cleared by "Cache-Control: max-age" and X-Accel-Expires). Additionally, now X-Accel-Expires does not prevent parsing of cache control extensions, notably stale-while-revalidate and stale-if-error. This ensures that order of the X-Accel-Expires and Cache-Control headers is not important. Prodded by Vadim Fedorenko and Yugo Horie.

VER=	$(shell grep 'define NGINX_VERSION' src/core/nginx.h		\
		| sed -e 's/^.*"\(.*\)".*/\1/')
NGINX=	nginx-$(VER)
TEMP=	tmp
XSLS?=	xslscript.pl


all:		changes

changes:	$(TEMP)/$(NGINX)/CHANGES.ru				\
		$(TEMP)/$(NGINX)/CHANGES


$(TEMP)/$(NGINX)/CHANGES.ru:	docs/dtd/changes.dtd			\
				docs/xml/nginx/changes.xml		\
				docs/xml/change_log_conf.xml		\
				docs/xslt/changes.xslt

	mkdir -p $(TEMP)/$(NGINX)

	xmllint --noout --valid docs/xml/nginx/changes.xml
	xsltproc --stringparam lang ru					\
		-o $@ docs/xslt/changes.xslt docs/xml/nginx/changes.xml


$(TEMP)/$(NGINX)/CHANGES:	docs/dtd/changes.dtd			\
				docs/xml/nginx/changes.xml		\
				docs/xml/change_log_conf.xml		\
				docs/xslt/changes.xslt

	mkdir -p $(TEMP)/$(NGINX)

	xmllint --noout --valid docs/xml/nginx/changes.xml
	xsltproc --stringparam lang en					\
		-o $@ docs/xslt/changes.xslt docs/xml/nginx/changes.xml


docs/xslt/changes.xslt:		docs/xsls/changes.xsls

	$(XSLS) -o $@ $<