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.

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


echo $ngx_n "checking for system byte ordering ...$ngx_c"

cat << END >> $NGX_AUTOCONF_ERR

----------------------------------------
checking for system byte ordering

END


cat << END > $NGX_AUTOTEST.c

int main(void) {
    int i = 0x11223344;
    char *p;

    p = (char *) &i;
    if (*p == 0x44) return 0;
    return 1;
}

END

ngx_test="$CC $CC_TEST_FLAGS $CC_AUX_FLAGS \
          -o $NGX_AUTOTEST $NGX_AUTOTEST.c $NGX_LD_OPT $ngx_feature_libs"

eval "$ngx_test >> $NGX_AUTOCONF_ERR 2>&1"

if [ -x $NGX_AUTOTEST ]; then
    if $NGX_AUTOTEST >/dev/null 2>&1; then
        echo " little endian"
        have=NGX_HAVE_LITTLE_ENDIAN . auto/have
    else
        echo " big endian"
    fi

    rm -rf $NGX_AUTOTEST*

else
    rm -rf $NGX_AUTOTEST*

    echo
    echo "$0: error: cannot detect system byte ordering"
    exit 1
fi