network: return negative idx for legacy networks

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

diff --git a/src/lxc/confile_network_legacy.c b/src/lxc/confile_network_legacy.c
index 33a053b1e8f89ef6fe2fdab3ddb5600f1073e8cd..14aef21ea06ba50f8a9265c211b4229439bb4f69 100644 (file)
--- a/src/lxc/confile_network_legacy.c
+++ b/src/lxc/confile_network_legacy.c
@@ -229,13 +229,18 @@ static int get_network_netdev_idx(const char *key)
        int ret, idx;
 
        if (*key < '0' || *key > '9')
-               return -1;
+               return EINVAL;
 
        ret = sscanf(key, "%d", &idx);
        if (ret != 1)
-               return -1;
+               return EINVAL;
 
-       return idx;
+       /* Since we've implemented the new network parser legacy networks are
+        * recorded using a negative index starting from -1. To preserve the old
+        * behavior we need this function to return the appropriate negative
+        * index.
+        */
+       return -(++idx);
 }
 
 /*
@@ -247,21 +252,19 @@ static struct lxc_netdev *get_netdev_from_key(const char *key,
 {
        int idx;
        struct lxc_list *it;
-       int i = 0;
        struct lxc_netdev *netdev = NULL;
 
        idx = get_network_netdev_idx(key);
-       if (idx == -1)
+       if (idx == EINVAL)
                return NULL;
 
        lxc_list_for_each(it, network) {
-               if (idx == i++) {
-                       netdev = it->elem;
-                       break;
-               }
+               netdev = it->elem;
+               if (idx == netdev->idx)
+                       return netdev;
        }
 
-       return netdev;
+       return NULL;
 }
 
 int lxc_list_nicconfigs_legacy(struct lxc_conf *c, const char *key, char *retv,
@@ -323,7 +326,7 @@ static struct lxc_netdev *network_netdev(const char *key, const char *value,
                return NULL;
        }
 
-       if (get_network_netdev_idx(key + 12) == -1)
+       if (get_network_netdev_idx(key + 12) == EINVAL)
                netdev = lxc_list_last_elem(network);
        else
                netdev = get_netdev_from_key(key + 12, network);