diff --git a/src/core/ngx_string.h b/src/core/ngx_string.h
index 0a78a06..de9b14b 100644
--- a/src/core/ngx_string.h
+++ b/src/core/ngx_string.h
@@ -5,6 +5,11 @@
 #include <ngx_config.h>
 
 
+typedef struct {
+    int   len;
+    char *data;
+} ngx_str_t;
+
 #if (WIN32)
 
 #define ngx_snprintf              _snprintf