# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1382105624 -14400
# Node ID 7ed23dcfea3d3d7fa3924d924414bd9cb341b163
# Parent  4bfa982dbf0e3adda92c0b9657f3ee851a583c6e
Headers filter: empty Cache-Control is no longer added.

Much like with other headers, "add_header Cache-Control $value;" no longer
results in anything added to response headers if $value evaluates to an
empty string.

diff --git a/src/http/modules/ngx_http_headers_filter_module.c b/src/http/modules/ngx_http_headers_filter_module.c
--- a/src/http/modules/ngx_http_headers_filter_module.c
+++ b/src/http/modules/ngx_http_headers_filter_module.c
@@ -339,6 +339,10 @@ ngx_http_add_cache_control(ngx_http_requ
 {
     ngx_table_elt_t  *cc, **ccp;
 
+    if (value->len == 0) {
+        return NGX_OK;
+    }
+
     ccp = r->headers_out.cache_control.elts;
 
     if (ccp == NULL) {