netdev-bsd: Don't assume 'struct netdev' has offset 0.

The data items returned by netdev_get_devices() are "struct netdev *"s.
The code fixed up by this commit used them as "struct netdev_bsd *",
which happens to work because struct netdev happens to be at offset 0 in
each struct but it's better to do a proper cast in case someday
struct netdev gets moved to a nonzero offset.

Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/lib/netdev-bsd.c b/lib/netdev-bsd.c
index 79643e1..2e49c94 100644 (file)
--- a/lib/netdev-bsd.c
+++ b/lib/netdev-bsd.c
@@ -267,7 +267,8 @@ netdev_bsd_cache_cb(const struct rtbsd_change *change,
         shash_init(&device_shash);
         netdev_get_devices(&netdev_bsd_class, &device_shash);
         SHASH_FOR_EACH (node, &device_shash) {
         shash_init(&device_shash);
         netdev_get_devices(&netdev_bsd_class, &device_shash);
         SHASH_FOR_EACH (node, &device_shash) {

-            dev = node->data;
+            struct netdev *netdev = node->data;
+            dev = netdev_bsd_cast(netdev);

             dev->cache_valid = 0;
             netdev_bsd_changed(dev);
         }
             dev->cache_valid = 0;
             netdev_bsd_changed(dev);
         }


@@ -1208,7 +1209,8 @@ find_netdev_by_kernel_name(const char *kernel_name)
     shash_init(&device_shash);
     netdev_get_devices(&netdev_tap_class, &device_shash);
     SHASH_FOR_EACH(node, &device_shash) {
     shash_init(&device_shash);
     netdev_get_devices(&netdev_tap_class, &device_shash);
     SHASH_FOR_EACH(node, &device_shash) {

-        struct netdev_bsd * const dev = node->data;
+        struct netdev *netdev = node->data;
+        struct netdev_bsd * const dev = netdev_bsd_cast(netdev);

 
         if (!strcmp(dev->kernel_name, kernel_name)) {
             shash_destroy(&device_shash);
 
         if (!strcmp(dev->kernel_name, kernel_name)) {
             shash_destroy(&device_shash);