Add a "need_carrier" argument to nm_device_is_available(), to allow
distinguishing between "device is not available", "device is fully
available", and "device is available except for not having carrier".
Adjust various parts of NMDevice and NMManager to allow for the
possibility of activating a connection with :carrier-detect = "no" on
a device with no carrier, and to avoid auto-disconnecting devices with
:carrier-detect = "on-activate".
https://bugzilla.gnome.org/show_bug.cgi?id=688284
Move some duplicated carrier-handling code into NMDevice (which can
introspect itself to see if it's a subclass that has carrier).
The "mostly ignore carrier" special handling for bridges and bonds is
now also handled as part of the NMDevice-level carrier handling.
https://bugzilla.gnome.org/show_bug.cgi?id=688284
The bridge master's carrier follows IFF_UP when no ports are added
and the ports' carrier when ports are added, so we shouldn't
depend on carrier when deciding whether to activate a bridge which
may not have any ports. Also when the
The code flow is actually somewhat simpler this way since the
subclasses don't have to ask NMDeviceWired for the address
every time. Plus then NMDeviceWired doesn't have to know
anything about its subclasses in the constructor.
When no slave is present, dynamic IP configuration (DHCPv4, DHCPv6,
IPv6 autoconf) cannot proceed. But static and link-local
configuration can. So if IPv4 requires DHCP but IPv6 is static,
it makes no sense to block IPv6 configuration from proceeding
just because DHCPv4 cannot.
