libBLOC

diff --git a/tree/tree_remove.c b/tree/tree_remove.c
new file mode 100644
index 0000000..6510a03
--- /dev/null
+++ b/tree/tree_remove.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2023 Barry
+ *
+ * This file is part of Barry's Little Objects in C Library (libBLOC).
+ *
+ * libBLOC is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * libBLOC is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTIBILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * libBLOC.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <BLOC/object.h>
+#include <BLOC/tree.h>
+#include "../assert.h"
+#include "../object.h"
+#include "tree.h"
+
+/* Find a node recursively */
+static struct TreeNode *
+_tree_find(Tree *t, struct TreeNode *root, void *obj)
+{
+	if (!root)
+		return NULL;
+	if (root->header.obj == obj)
+		return root;
+	if (t->compare(root->header.obj, obj) > 0)
+		return _tree_find(t, root->left, obj);
+	else
+		return _tree_find(t, root->right, obj);
+}
+
+/* Remove a node from a tree recursively */
+static struct TreeNode *
+_tree_remove_r(Tree *t, struct TreeNode *parent, struct TreeNode *child)
+{
+	/* Remove node */
+	struct TreeNode *tmp;
+	if (t->compare(parent->header.obj, child->header.obj) > 0) {
+		parent->left = _tree_remove_r(t, parent->left, child);
+	} else if (t->compare(parent->header.obj, child->header.obj) < 0) {
+		parent->right = _tree_remove_r(t, parent->right, child);
+	} else {
+		/* Less that two children: adopt child if available */
+		if (!child->left)
+			return child->right;
+		if (!child->right)
+			return child->left;
+		/* Two children: swap for logical successor */
+		tmp = (struct TreeNode *) child->header.next;
+		if (child->right != tmp)
+			tmp->right = _tree_remove_r(t, child->right, tmp);
+		tmp->left = child->left;
+		return tmp;
+	}
+
+	/* Balance */
+	if (_tree_count(parent->right) > _tree_count(parent->left) + 1)
+		return _tree_rotate_left(parent);
+	if (_tree_count(parent->left) > _tree_count(parent->right) + 1)
+		return _tree_rotate_right(parent);
+	return parent;
+}
+
+/* Remove an object from a tree */
+void
+tree_remove(Tree *tree, void *obj)
+{
+	ASSERT(tree);
+	ASSERT(obj);
+	struct ObjectHeader *header = object_header(obj);
+	ASSERT(header->magic == OBJECT_MAGIC);
+	if (!tree->header.start)
+		return;
+	if (tree->type && tree->type != header->type)
+		return;
+	obj_lock(tree);
+
+	/* Search for object */
+	struct TreeNode *node = _tree_find(tree, tree->root, obj);
+	if (!node) {
+		obj_unlock(tree);
+		return;
+	}
+
+	/* Unlink from tree */
+	tree->root = _tree_remove_r(tree, tree->root, node);
+
+	/* Unlink from linear list*/
+	if (tree->header.start == &node->header)
+		tree->header.start = node->header.next;
+	if (tree->header.end == &node->header)
+		tree->header.end = node->header.prev;
+	if (node->header.prev)
+		node->header.prev->next = node->header.next;
+	if (node->header.next)
+		node->header.next->prev = node->header.prev;
+
+	obj_put(node->header.obj);
+	tree->header.entries--;
+	free(node);
+
+	obj_unlock(tree);
+}