From 05e910cec691f8333383a746876015e99ff088db Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 2 Oct 2011 19:22:08 +0200
Subject: [PATCH] make versioned lists more flexible by using an external
 comparator

---
 interface-ip.c | 27 ++++++++++++++++++++++-----
 interface-ip.h |  7 +++++--
 utils.c        | 20 +++++++-------------
 utils.h        | 11 ++++-------
 4 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/interface-ip.c b/interface-ip.c
index 2e2e9d8..0845169 100644
--- a/interface-ip.c
+++ b/interface-ip.c
@@ -10,6 +10,24 @@
 #include "ubus.h"
 #include "system.h"
 
+static int
+addr_cmp(const void *k1, const void *k2, void *ptr)
+{
+	const struct device_addr *a1 = k1, *a2 = k2;
+
+	return memcmp(&a1->mask, &a2->mask,
+		sizeof(*a1) - offsetof(struct device_addr, mask));
+}
+
+static int
+route_cmp(const void *k1, const void *k2, void *ptr)
+{
+	const struct device_route *r1 = k1, *r2 = k2;
+
+	return memcmp(&r1->mask, &r2->mask,
+		sizeof(*r1) - offsetof(struct device_route, mask));
+}
+
 static void
 interface_update_proto_addr(struct vlist_tree *tree,
 			    struct vlist_node *node_new,
@@ -65,9 +83,8 @@ interface_update_proto_route(struct vlist_tree *tree,
 void
 interface_ip_init(struct interface *iface)
 {
-	vlist_init(&iface->proto_route, interface_update_proto_route,
-		   struct device_route, node, mask, addr);
-	vlist_init(&iface->proto_addr, interface_update_proto_addr,
-		   struct device_addr, node, mask, addr);
+	vlist_init(&iface->proto_route, route_cmp, interface_update_proto_route,
+		   struct device_route, node);
+	vlist_init(&iface->proto_addr, addr_cmp, interface_update_proto_addr,
+		   struct device_addr, node);
 }
-
diff --git a/interface-ip.h b/interface-ip.h
index ba7b6c8..057f0d0 100644
--- a/interface-ip.h
+++ b/interface-ip.h
@@ -24,6 +24,7 @@ struct device_addr {
 
 	enum device_addr_flags flags;
 
+	/* must be last */
 	unsigned int mask;
 	union if_addr addr;
 };
@@ -34,10 +35,12 @@ struct device_route {
 	enum device_addr_flags flags;
 	bool keep;
 
-	unsigned int mask;
-	union if_addr addr;
 	union if_addr nexthop;
 	struct device *device;
+
+	/* must be last */
+	unsigned int mask;
+	union if_addr addr;
 };
 
 void interface_ip_init(struct interface *iface);
diff --git a/utils.c b/utils.c
index 15f0525..42d3176 100644
--- a/utils.c
+++ b/utils.c
@@ -7,22 +7,15 @@ 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)
+__vlist_init(struct vlist_tree *tree, avl_tree_comp cmp,
+	     vlist_update_cb update, int offset)
 {
-	tree->data_offset = offset;
-	tree->data_len = len;
+	tree->node_offset = offset;
 	tree->update = update;
 	tree->version = 1;
 
-	avl_init(&tree->avl, vlist_cmp, 0, tree);
+	avl_init(&tree->avl, cmp, 0, tree);
 }
 
 void
@@ -37,11 +30,12 @@ vlist_add(struct vlist_tree *tree, struct vlist_node *node)
 {
 	struct vlist_node *old_node = NULL;
 	struct avl_node *anode;
+	void *key = (char *) node - tree->node_offset;
 
-	node->avl.key = (char *) node + tree->data_offset;
+	node->avl.key = key;
 	node->version = tree->version;
 
-	anode = avl_find(&tree->avl, (char *) node + tree->data_offset);
+	anode = avl_find(&tree->avl, key);
 	if (anode) {
 		old_node = container_of(anode, struct vlist_node, avl);
 		avl_delete(&tree->avl, anode);
diff --git a/utils.h b/utils.h
index e872dc5..c8101e7 100644
--- a/utils.h
+++ b/utils.h
@@ -27,9 +27,7 @@ struct vlist_tree {
 	struct avl_tree avl;
 
 	vlist_update_cb update;
-
-	int data_offset;
-	int data_len;
+	int node_offset;
 
 	int version;
 };
@@ -39,11 +37,10 @@ struct vlist_node {
 	int version;
 };
 
-void __vlist_init(struct vlist_tree *tree, vlist_update_cb update, int offset, int len);
+void __vlist_init(struct vlist_tree *tree, avl_tree_comp cmp, vlist_update_cb update, int offset);
 
-#define vlist_init(tree, update, type, vlist, first, last) \
-	__vlist_init(tree, update, offsetof(type, first) - offsetof(type, vlist), \
-		     offsetof(type, last) - offsetof(type, first) + sizeof(((type *) 0)->last))
+#define vlist_init(tree, cmp, update, type, node) \
+	__vlist_init(tree, cmp, update, offsetof(type, node))
 
 void vlist_add(struct vlist_tree *tree, struct vlist_node *node);
 void vlist_delete(struct vlist_tree *tree, struct vlist_node *node);
-- 
2.25.1