confile_utils: improve network parser

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

src/lxc/confile.c

@@ -545,8 +545,8 @@ static int set_config_net_ipvlan_isolation(const char *key, const char *value,
 static int set_config_net_hwaddr(const char *key, const char *value,
 				 struct lxc_conf *lxc_conf, void *data)
 {
+	__do_free char *new_value = NULL;
 	struct lxc_netdev *netdev = data;
-	char *new_value;
 
 	if (lxc_config_value_empty(value))
 		return clr_config_net_hwaddr(key, lxc_conf, data);
@@ -560,13 +560,10 @@ static int set_config_net_hwaddr(const char *key, const char *value,
 
 	rand_complete_hwaddr(new_value);
 
-	if (lxc_config_value_empty(new_value)) {
-		free(new_value);
-		netdev->hwaddr = NULL;
-		return 0;
-	}
-
-	netdev->hwaddr = new_value;
+	if (lxc_config_value_empty(new_value))
+		free_disarm(netdev->hwaddr);
+	else
+		netdev->hwaddr = move_ptr(new_value);
 
 	return 0;
 }

src/lxc/confile_utils.c

@@ -169,19 +169,16 @@ struct lxc_netdev *lxc_network_add(struct lxc_list *networks, int idx, bool tail
 	if (!netdev)
 		return ret_set_errno(NULL, ENOMEM);
 
-	memset(netdev, 0, sizeof(*netdev));
 	lxc_list_init(&netdev->ipv4);
 	lxc_list_init(&netdev->ipv6);
 
 	/* give network a unique index */
 	netdev->idx = idx;
 
 	/* prepare new list */
-	newlist = zalloc(sizeof(*newlist));
+	newlist = lxc_list_new();
 	if (!newlist)
 		return ret_set_errno(NULL, ENOMEM);
-
-	lxc_list_init(newlist);
 	newlist->elem = netdev;
 
 	if (tail)
@@ -199,25 +196,27 @@ struct lxc_netdev *lxc_network_add(struct lxc_list *networks, int idx, bool tail
 struct lxc_netdev *lxc_get_netdev_by_idx(struct lxc_conf *conf,
 					 unsigned int idx, bool allocate)
 {
-	struct lxc_netdev *netdev = NULL;
 	struct lxc_list *networks = &conf->network;
 	struct lxc_list *insert = networks;
 
 	/* lookup network */
 	if (!lxc_list_empty(networks)) {
 		lxc_list_for_each(insert, networks) {
-			netdev = insert->elem;
+			struct lxc_netdev *netdev = insert->elem;
+
+			/* found network device */
 			if (netdev->idx == idx)
 				return netdev;
-			else if (netdev->idx > idx)
+
+			if (netdev->idx > idx)
 				break;
 		}
 	}
 
-	if (!allocate)
-		return ret_set_errno(NULL, EINVAL);
+	if (allocate)
+		return lxc_network_add(insert, idx, true);
 
-	return lxc_network_add(insert, idx, true);
+	return NULL;
 }
 
 void lxc_log_configured_netdevs(const struct lxc_conf *conf)
@@ -452,19 +451,21 @@ static void lxc_free_netdev(struct lxc_netdev *netdev)
 	free(netdev);
 }
 
-define_cleanup_function(struct lxc_netdev *, lxc_free_netdev);
-
 bool lxc_remove_nic_by_idx(struct lxc_conf *conf, unsigned int idx)
 {
-	call_cleaner(lxc_free_netdev) struct lxc_netdev *netdev = NULL;
 	struct lxc_list *cur, *next;
 
+	if (lxc_list_empty(&conf->network))
+		return false;
+
 	lxc_list_for_each_safe(cur, &conf->network, next) {
-		netdev = cur->elem;
+		struct lxc_netdev *netdev = cur->elem;
+
 		if (netdev->idx != idx)
 			continue;
 
 		lxc_list_del(cur);
+		lxc_free_netdev(netdev);
 		return true;
 	}