Add rbtree iterator implementation

src/__internal/include.h

@@ -64,6 +64,17 @@ extern int    libcdsb_builtin_vtype_compare_values   (const void* s0, vtype t0,
 extern int    libcdsb_builtin_vtype_compare_values_eq(const void* s0, const void* s1, vtype t)            pure__ wur__;
 extern hash_t libcdsb_builtin_vtype_hash             (const void* value, vtype type)                      pure__ wur__;
 
+ainline(stack_t* libcdsb_builtin_stack_insert(stack_t* x, void* v)) {
+    stack_t* p = x->prev;
+
+    if (!is_null(x->prev = malloc(sizeof(*x)))) {
+        x->prev->prev  = p;
+        x->prev->value = v;
+    } else abort();
+
+    return x->prev;
+}
+
 #define aligned_alloc   libcdsb_aalloc
 #define malloc          libcdsb_malloc
 #define calloc          libcdsb_calloc
@@ -72,7 +83,9 @@ extern hash_t libcdsb_builtin_vtype_hash             (const void* value, vtype t
 #define stack_init      libcdsb_stack_init
 #define stack_push      libcdsb_stack_push
 #define stack_push_many libcdsb_stack_push_many
+#define stack_insert    libcdsb_builtin_stack_insert
 #define stack_pop       libcdsb_stack_pop
+#define stack_reverse   libcdsb_stack_reverse
 #define stack_flush     libcdsb_stack_flush
 #define strlen          libcdsb_strlen
 #define strasciilen     libcdsb_strasciilen