make global the rbtree color handling macros

src/core/ngx_rbtree.c

diff --git a/src/core/ngx_rbtree.c b/src/core/ngx_rbtree.c
index a9d6305..0a5753c 100644
--- a/src/core/ngx_rbtree.c
+++ b/src/core/ngx_rbtree.c
@@ -13,12 +13,6 @@
  * the "Introduction to Algorithms" by Cormen, Leiserson and Rivest.
  */
 
-#define ngx_rbt_red(node)           ((node)->color = 1)
-#define ngx_rbt_black(node)         ((node)->color = 0)
-#define ngx_rbt_is_red(node)        ((node)->color)
-#define ngx_rbt_is_black(node)      (!ngx_rbt_is_red(node))
-#define ngx_rbt_copy_color(n1, n2)  (n1->color = n2->color)
-
 
 static ngx_inline void ngx_rbtree_left_rotate(ngx_rbtree_node_t **root,
     ngx_rbtree_node_t *sentinel, ngx_rbtree_node_t *node);

src/core/ngx_rbtree.h

diff --git a/src/core/ngx_rbtree.h b/src/core/ngx_rbtree.h
index 16524ff..d7250f8 100644
--- a/src/core/ngx_rbtree.h
+++ b/src/core/ngx_rbtree.h
@@ -50,9 +50,16 @@
     ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel);
 
 
+#define ngx_rbt_red(node)               ((node)->color = 1)
+#define ngx_rbt_black(node)             ((node)->color = 0)
+#define ngx_rbt_is_red(node)            ((node)->color)
+#define ngx_rbt_is_black(node)          (!ngx_rbt_is_red(node))
+#define ngx_rbt_copy_color(n1, n2)      (n1->color = n2->color)
+
+
 /* a sentinel must be black */
 
-#define ngx_rbtree_sentinel_init(node)   node->color = 0
+#define ngx_rbtree_sentinel_init(node)  ngx_rbt_black(node)
 
 
 static ngx_inline ngx_rbtree_node_t *