nspawn: add new --network-zone= switch for automatically managed bridge devices

This adds a new concept of network "zones", which are little more than bridge
devices that are automatically managed by nspawn: when the first container
referencing a bridge is started, the bridge device is created, when the last
container referencing it is removed the bridge device is removed again. Besides
this logic --network-zone= is pretty much identical to --network-bridge=.

The usecase for this is to make it easy to run multiple related containers
(think MySQL in one and Apache in another) in a common, named virtual Ethernet
broadcast zone, that only exists as long as one of them is running, and fully
automatically managed otherwise.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/nspawn/nspawn-network.h b/src/nspawn/nspawn-network.h
index c5036ab470..3d8861e1e5 100644
--- a/src/nspawn/nspawn-network.h
+++ b/src/nspawn/nspawn-network.h
@@ -26,7 +26,8 @@
 int setup_veth(const char *machine_name, pid_t pid, char iface_name[IFNAMSIZ], bool bridge);
 int setup_veth_extra(const char *machine_name, pid_t pid, char **pairs);
 
-int setup_bridge(const char *veth_name, const char *bridge_name);
+int setup_bridge(const char *veth_name, const char *bridge_name, bool create);
+int remove_bridge(const char *bridge_name);
 
 int setup_macvlan(const char *machine_name, pid_t pid, char **ifaces);
 int setup_ipvlan(const char *machine_name, pid_t pid, char **ifaces);