Created a macro for tree find to prevent duplicating this code in insert and delete.

include/tr/tree.h

@@ -29,6 +29,27 @@
 #define TR_TREE_LEFT(node)		(NULL!=(node)?(node)->left:NULL)
 #define TR_TREE_PARENT(node)	(NULL!=(node)?(node)->parent:NULL)
 
+/*
+ * Find data in a tree. 
+ * Attention: This will change node, so normally you need to copy
+ * it before using this macro.
+ * Also be aware that found needs to be a valid lvalue and an integer.
+ */
+#define TR_TREE_FIND(node, search, found, comp)        \
+	(found) = -1;                                      \
+	while((node) && ((node)->left || (node)->right)) { \
+		(found) = (comp)((node)->data, (search));      \
+		if (0 != (found)) {                            \
+			if (0 < (found)) {                         \
+				(node) = (node)->left;                 \
+			} else {                                   \
+				(node) = (node)->right;                \
+			}                                          \
+		} else {                                       \
+			break;                                     \
+		}                                              \
+	}
+
 #define TR_TREE_CHILD(node) \
 	(NULL==TR_TREE_RIGHT((node))?TR_TREE_LEFT((node)):TR_TREE_RIGHT((node)))
 

src/tree/delete.c

@@ -28,35 +28,16 @@ TR_treeDelete(TR_Tree * this, const void * search, TR_TreeComp comp)
 {
 	TR_Tree   node = *this;
 	TR_Tree   del_node;
+	int       found;
 
 	void    * data;
 
-	/*
-	 * first search for it and if its found return the data
-	 * and we are done...
-	 */
-	while (NULL != node) {
-		int comparison = comp(node->data, search);
-
-		if (0 < comparison) {
-			node = TR_TREE_LEFT(node);
-			continue;
-		}
-
-		if (0 > comparison) {
-			node = TR_TREE_RIGHT(node);
-			continue;
-		}
-
-		if (0 == comparison) {
-			break;
-		}
-	}   
+	TR_TREE_FIND(node, search, found, comp);
 
 	/*
 	 * nothing was found...return NULL to indicate this.
 	 */
-	if (NULL == node) {
+	if (found != 0) {
 		return NULL;
 	}
 

src/tree/find.c

@@ -25,25 +25,12 @@
 void *
 TR_treeFind(TR_Tree this, const void * search, TR_TreeComp comp)
 {
-	while (NULL != this) {
-		int comparison = comp(this->data, search);
+	TR_Tree node = this;
+	int     found;
 
-		if (0 < comparison) {
-			this = TR_TREE_LEFT(this);
-			continue;
-		}
+	TR_TREE_FIND(node, search, found, comp);
 
-		if (0 > comparison) {
-			this = TR_TREE_RIGHT(this);
-			continue;
-		}
-
-		if (0 == comparison) {
-			break;
-		}
-	}   
-
-	return NULL != this ? this->data : NULL;
+	return found == 0 ? node->data : NULL;
 }
 
 // vim: set ts=4 sw=4:

src/tree/insert.c

@@ -28,6 +28,9 @@ TR_treeInsert(TR_Tree * this, const void * search, TR_TreeComp comp)
 {
 	TR_Tree node     = *this;
 	TR_Tree new_node = NULL;
+	int     found;
+
+	TR_TREE_FIND(node, search, found, comp);
 
 	/*
 	 * insert the node or return the one in tree if comparison
@@ -40,43 +43,24 @@ TR_treeInsert(TR_Tree * this, const void * search, TR_TreeComp comp)
 		 */
 		*this = node = new_node = TR_new(TR_Tree, search);
 	} else {
-		/*
-		 * first search for it and if its found return the data
-		 * and we are done...
-		 */
-		while (NULL != node) {
-			int comparison = comp(node->data, search);
-
-			if (0 < comparison) {
-				if (NULL != TR_TREE_LEFT(node)) {
-					node = TR_TREE_LEFT(node);
-					continue;
-				} else {
-					node->left = TR_new(TR_Tree, search);
-					node->left->parent = node;
-					node = new_node = node->left;
-					break;
-				}
-			}
-
-			if (0 > comparison) {
-				if (NULL != TR_TREE_RIGHT(node)) {
-					node = TR_TREE_RIGHT(node);
-					continue;
-				} else {
-					node->right = TR_new(TR_Tree, search);
-					node->right->parent = node;
-					node = new_node = node->right;
-					break;
-				}
-			}
-
-			if (0 == comparison) {
-				// as this is insert and not find this will overwrite an existing value,
-				// but return the previos one so that it can be freed if neccessary.
-				void * data = node->data;
-				node->data = (void *)search;
-				return data;
+		if (found == 0) {
+			// we found an element
+			// as this is insert and not find this will overwrite an existing
+			// value, but return the previous one so that it can be freed if
+			// neccessary.
+			void * data = node->data;
+			node->data = (void *)search;
+			return data;
+		} else {
+			// not found
+			if (0 < found) {
+				node->left = TR_new(TR_Tree, search);
+				node->left->parent = node;
+				node = new_node = node->left;
+			} else {
+				node->right = TR_new(TR_Tree, search);
+				node->right->parent = node;
+				node = new_node = node->right;
 			}
 		}
 	}
@@ -114,13 +98,13 @@ TR_treeInsert(TR_Tree * this, const void * search, TR_TreeComp comp)
 				&& node->parent == node->parent->parent->left) {
 
 			TR_TREE_ROTATE(left, this, node->parent);
-			node = TR_TREE_LEFT(node);
+			node = node->left;
 
 		} else if (node == node->parent->left
 				&& node->parent == node->parent->parent->right) {
 
 			TR_TREE_ROTATE(right, this, node->parent);
-			node = TR_TREE_RIGHT(node);
+			node = node->right;
 
 		}
 

trdata.h

@@ -11,13 +11,13 @@
 #define HAVE_MEMORY_H 1
 
 /* Define to 1 if you have the `memset' function. */
-/* #undef HAVE_MEMSET */
+#define HAVE_MEMSET 1
 
 /* Define to 1 if you have the <stdarg.h> header file. */
 #define HAVE_STDARG_H 1
 
 /* Define to 1 if stdbool.h conforms to C99. */
-/* #undef HAVE_STDBOOL_H */
+#define HAVE_STDBOOL_H 1
 
 /* Define to 1 if you have the <stdint.h> header file. */
 #define HAVE_STDINT_H 1