[netcf-devel] [PATCH] fix wrong status of bridge devices

[Hendrik Schwartke]

The IFF_RUNNING flag is not set on a bridge device if there are no
devices attached to it. So bridges without attached devices are reported
as inactive. Destroying inactive devices leads to an error and thus the
device can't be removed (easily) from the operating system.

This patch checks if the device is a bridge and if so ignores the IFF_RUNNING
flag.
---
 src/dutil_linux.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/dutil_linux.c b/src/dutil_linux.c
index 7af741e..2db166a 100644
--- a/src/dutil_linux.c
+++ b/src/dutil_linux.c
@@ -456,6 +456,15 @@ void modprobed_unalias_bond(struct netcf *ncf, const char *name) {
 
 int if_is_active(struct netcf *ncf, const char *intf) {
     struct ifreq ifr;
+    short flags_to_check = IFF_UP;
+
+    /*
+     * IFF_RUNNING is set on a bridge only if there is at least one
+     * network device attached.
+     */
+    if(if_type(ncf, intf) != NETCF_IFACE_TYPE_BRIDGE) {
+        flags_to_check |= IFF_RUNNING;
+    }
 
     MEMZERO(&ifr, 1);
     strncpy(ifr.ifr_name, intf, sizeof(ifr.ifr_name));
@@ -463,7 +472,7 @@ int if_is_active(struct netcf *ncf, const char *intf) {
     if (ioctl(ncf->driver->ioctl_fd, SIOCGIFFLAGS, &ifr))  {
         return 0;
     }
-    return ((ifr.ifr_flags & (IFF_UP|IFF_RUNNING)) == (IFF_UP|IFF_RUNNING));
+    return ((ifr.ifr_flags & flags_to_check) == flags_to_check);
 }
 
 netcf_if_type_t if_type(struct netcf *ncf, const char *intf) {
-- 
1.9.1