1 files changed, 65 insertions, 1 deletions
diff --git a/utils.c b/utils.c
index cf0718a..15f0525 100644
--- a/utils.c
+++ b/utils.c
@@ -1,8 +1,72 @@
 #include <string.h>
 #include "utils.h"
 
-int avl_strcmp(const void *k1, const void *k2, void *ptr)
+int
+avl_strcmp(const void *k1, const void *k2, void *ptr)
 {
 	return strcmp(k1, k2);
 }
 
+static int
+vlist_cmp(const void *k1, const void *k2, void *ptr)
+{
+	struct vlist_tree *vl = ptr;
+	return memcmp(k1, k2, vl->data_len);
+}
+
+void
+__vlist_init(struct vlist_tree *tree, vlist_update_cb update, int offset, int len)
+{
+	tree->data_offset = offset;
+	tree->data_len = len;
+	tree->update = update;
+	tree->version = 1;
+
+	avl_init(&tree->avl, vlist_cmp, 0, tree);
+}
+
+void
+vlist_delete(struct vlist_tree *tree, struct vlist_node *node)
+{
+	avl_delete(&tree->avl, &node->avl);
+	tree->update(tree, NULL, node);
+}
+
+void
+vlist_add(struct vlist_tree *tree, struct vlist_node *node)
+{
+	struct vlist_node *old_node = NULL;
+	struct avl_node *anode;
+
+	node->avl.key = (char *) node + tree->data_offset;
+	node->version = tree->version;
+
+	anode = avl_find(&tree->avl, (char *) node + tree->data_offset);
+	if (anode) {
+		old_node = container_of(anode, struct vlist_node, avl);
+		avl_delete(&tree->avl, anode);
+	}
+
+	avl_insert(&tree->avl, &node->avl);
+	tree->update(tree, node, old_node);
+}
+
+void
+vlist_flush(struct vlist_tree *tree)
+{
+	struct vlist_node *node, *tmp;
+
+	avl_for_each_element_safe(&tree->avl, node, avl, tmp) {
+		if (node->version == tree->version)
+			continue;
+
+		vlist_delete(tree, node);
+	}
+}
+
+void
+vlist_flush_all(struct vlist_tree *tree)
+{
+	tree->version++;
+	vlist_flush(tree);
+}