From 1526d634034670d57a21f8361df35c7830e451bc Mon Sep 17 00:00:00 2001
From: Jan Vidar Krey <janvidar@extatic.org>
Date: Tue, 5 Aug 2014 13:08:46 +0200
Subject: [PATCH] Simplify list_clear(), allow NULL as free() function pointer.

This makes it redundant to create a null_free() or dummy_free() function
that does nothing.
---
 src/core/commands.c       | 6 ++----
 src/network/dnsresolver.c | 7 +------
 src/util/list.c           | 5 +++++
 src/util/rbtree.c         | 4 +---
 4 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/src/core/commands.c b/src/core/commands.c
index d808ffc..ef3e4e5 100644
--- a/src/core/commands.c
+++ b/src/core/commands.c
@@ -31,8 +31,6 @@ static int send_command_not_found(struct command_base* cbase, struct hub_user* u
 static int send_command_syntax_error(struct command_base* cbase, struct hub_user* user);
 static int send_command_missing_arguments(struct command_base* cbase, struct hub_user* user, struct hub_command* cmd);
 
-static void null_free(void* ptr) { }
-
 struct command_base
 {
 	struct hub_info* hub;
@@ -424,7 +422,7 @@ static int command_whoip(struct command_base* cbase, struct hub_user* user, stru
 	ret = uman_get_user_by_addr(cbase->hub->users, users, arg->data.range);
 	if (!ret)
 	{
-		list_clear(users, &null_free);
+		list_clear(users, NULL);
 		list_destroy(users);
 		return command_status(cbase, user, cmd, cbuf_create_const("No users found."));
 	}
@@ -439,7 +437,7 @@ static int command_whoip(struct command_base* cbase, struct hub_user* user, stru
 	cbuf_append(buf, "\n");
 
 	send_message(cbase, user, buf);
-	list_clear(users, &null_free);
+	list_clear(users, NULL);
 	list_destroy(users);
 	return 0;
 }
diff --git a/src/network/dnsresolver.c b/src/network/dnsresolver.c
index c470d13..d3ff25e 100644
--- a/src/network/dnsresolver.c
+++ b/src/network/dnsresolver.c
@@ -109,11 +109,6 @@ void net_dns_destroy()
 	g_dns = NULL;
 }
 
-static void dummy_free(void* ptr)
-{
-}
-
-
 void net_dns_process()
 {
 	struct net_dns_result* result;
@@ -148,7 +143,7 @@ void net_dns_process()
 		}
 	});
 
-	list_clear(g_dns->results, &dummy_free);
+	list_clear(g_dns->results, NULL);
 	uhub_mutex_unlock(&g_dns->mutex);
 }
 
diff --git a/src/util/list.c b/src/util/list.c
index daba290..9e67dc8 100644
--- a/src/util/list.c
+++ b/src/util/list.c
@@ -40,11 +40,16 @@ void list_destroy(struct linked_list* list)
 	}
 }
 
+static void dummy_free(void* ptr)
+{
+}
 
 void list_clear(struct linked_list* list, void (*free_handle)(void* ptr))
 {
 	struct node* node = list->first;
 	struct node* tmp = NULL;
+	if (free_handle == NULL)
+		free_handle = &dummy_free;
 	while (node)
 	{
 		tmp = node->next;
diff --git a/src/util/rbtree.c b/src/util/rbtree.c
index 3fb4e99..ae61f2e 100644
--- a/src/util/rbtree.c
+++ b/src/util/rbtree.c
@@ -318,12 +318,10 @@ static struct rb_node* rb_it_set(struct rb_tree* tree, struct rb_node* n)
 	return n;
 }
 
-static void null_free(void* ptr) { }
-
 struct rb_node* rb_tree_first(struct rb_tree* tree)
 {
 	struct rb_node* n = tree->root;
-	list_clear(tree->iterator.stack, &null_free);
+	list_clear(tree->iterator.stack, NULL);
 	while (n->link[0])
 	{
 		push(tree, n);