Upstream: avoid closing client connection in edge case. If proxy_cache is enabled, and proxy_no_cache tests true, it was previously possible for the client connection to be closed after a 304. The fix is to recheck r->header_only after the final cacheability is determined, and end the request if no longer cacheable. Example configuration: proxy_cache foo; proxy_cache_bypass 1; proxy_no_cache 1; If a client sends If-None-Match, and the upstream server returns 200 with a matching ETag, no body should be returned to the client. At the start of ngx_http_upstream_send_response proxy_no_cache is not yet tested, thus cacheable is still 1 and downstream_error is set. However, by the time the downstream_error check is done in process_request, proxy_no_cache has been tested and cacheable is set to 0. The client connection is then closed, regardless of keepalive.

ngx_addon_name=ngx_mysql

HTTP_MODULES="$HTTP_MODULES ngx_http_mysql_test_module"

HTTP_INCS="$HTTP_INCS $ngx_addon_dir"
HTTP_DEPS="$HTTP_DEPS $ngx_addon_dir/ngx_mysql.h"
#CORE_LIBS="$CORE_LIBS -lmd"

USE_SHA1=YES

NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/ngx_mysql.c"
NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_mysql_test.c"