Add documentation

include/ucore/rbtree.h

@@ -26,11 +26,66 @@ struct RBTree {
 	int (*compare)(const void *a, const void *b);
 };
 
+/** Remove a node from the tree.
+ *
+ * @param root Root of the tree
+ * @param node Node to remove, the node must exist in the tree
+ */
 void uc_rb_remove(RBTree *root, RBNode *node);
+
+/** Find a node in the tree.
+ *
+ * The value to find will be in a node->data pointer, the compare
+ * function of the tree is used to find the matching item.
+ *
+ * @param root Root of the tree
+ * @param val The value to find.
+ * @return the found node
+ */
 RBNode *uc_rb_find(RBTree *root, const void *val);
+
+/** insert a new node
+ *
+ * The actual value to insert must be in node->data.
+ * Of node->data matches an existing item in the tree,
+ * the existing node will be replaced and returned.
+ *
+ * @param root Root of the tree
+ * @param child The node to insert
+ * @return NULL, or an existing node if the new node replaced
+ *         an existing node.
+ */
 RBNode *uc_rb_insert(RBTree *root, RBNode *child);
+
+/** get the first node in the tree.
+ * the tree keeps the items in a sorted order, this
+ * will be the node where the compare function determins as the
+ * smallest node.
+ *
+ * @param root Root of the tree
+ * @return the first node, or null if the tree is empty
+ */
 RBNode *uc_rb_first(const RBTree *root);
+
+/** Get the next node in the tree.
+ * the tree keeps the items in a sorted order, this
+ * will be the node after, based on the compare function ,
+ * the given node
+ *
+ * @param node The previous node
+ * @return the node after the passed in node, or NULL if the
+ *         passed in node was the last.
+ */
 RBNode *uc_rb_next(RBNode *node);
+
+/** Get the last node in the tree.
+ * the tree keeps the items in a sorted order, this
+ * will be the node where the compare function determins as the
+ * greatest node.
+ *
+ * @param root Root of the tree
+ * @return the last node, or null if the tree is empty
+ */
 RBNode *uc_rb_last(const RBTree *root);
 
 #ifdef __cplusplus