From: Elias Fleckenstein <eliasfleckenstein@web.de>
Date: Thu, 26 Aug 2021 11:09:01 +0000 (+0200)
Subject: Bintree: allow custom comparators
X-Git-Url: https://git.lizzy.rs/?a=commitdiff_plain;h=5f7ef396d3338db2377b226cc83b56ad507a1dd6;p=dragonstd.git

Bintree: allow custom comparators
---

diff --git a/bintree.c b/bintree.c
index f68fa1e..6587e12 100644
--- a/bintree.c
+++ b/bintree.c
@@ -2,11 +2,17 @@
 #include <stdlib.h>
 #include "bintree.h"
 
-Bintree bintree_create(size_t key_size)
+static int bintree_compare_mem(void *v1, void *v2, Bintree *tree)
+{
+	return memcmp(v1, v2, tree->key_size);
+}
+
+Bintree bintree_create(size_t key_size, BintreeComparator cmp)
 {
 	return (Bintree) {
 		.root = NULL,
 		.key_size = key_size,
+		.cmp = cmp ? cmp : &bintree_compare_mem,
 	};
 }
 
@@ -15,7 +21,7 @@ static BintreeNode **search_recursive(Bintree *tree, BintreeNode **nodeptr, void
 	if (*nodeptr) {
 		int cond;
 
-		if ((cond = memcmp((*nodeptr)->key, key, tree->key_size)) == 0)
+		if ((cond = tree->cmp((*nodeptr)->key, key, tree)) == 0)
 			return nodeptr;
 		else if (cond > 0)
 			return search_recursive(tree, &(*nodeptr)->left, key);
diff --git a/bintree.h b/bintree.h
index 0e6e877..9dd0cfa 100644
--- a/bintree.h
+++ b/bintree.h
@@ -3,6 +3,11 @@
 
 #include <stddef.h>
 
+struct Bintree;
+
+typedef int (*BintreeComparator)(void *v1, void *v2, struct Bintree *tree);
+typedef void (*BintreeFreeFunction)(void *value, void *arg);
+
 typedef struct BintreeNode
 {
 	void *key;
@@ -11,15 +16,14 @@ typedef struct BintreeNode
 	struct BintreeNode *right;
 } BintreeNode;
 
-typedef struct
+typedef struct Bintree
 {
 	BintreeNode *root;
 	size_t key_size;
+	BintreeComparator cmp;
 } Bintree;
 
-typedef void (*BintreeFreeFunction)(void *value, void *arg);
-
-Bintree bintree_create(size_t key_size);
+Bintree bintree_create(size_t key_size, BintreeComparator cmp);
 BintreeNode **bintree_search(Bintree *tree, void *key);
 void bintree_add_node(Bintree *tree, BintreeNode **nodeptr, void *key, void *value);
 void bintree_clear(Bintree *tree, BintreeFreeFunction func, void *arg);