These messages allow the guest to send the audio device volume to the
client. It uses an arbitrary scale of 16bits, which works good enough
for now.
Save VolumeState in {Playback,Record}State, so that we can send the
current volume on channel connection.
Note about future improvements:
- add exact dB support
- add client to guest volume change
Updated since v2:
- bumped record and playback interface minor version to allow
conditional compilation
Updated since v1:
- sync record volume on connection too
Since some spice C++ code is using code from common/, the C
functions need to be marked as such for the C++ compiler, otherwise
we'll get linkage issues.
Remove all uses of @end in the marshaller, instead just using
the C struct array-at-end-of-struct. To make this work we also remove
all use of @end for switches (making them C unions).
We drop the zero member of the notify message so that we can avoid this
use of @end for a primitive in the marshaller (plus its useless to send
over the wire).
We change the offsets and stuff in the migration messages to real pointers.
Right now we always assume pointers are stored as SPICE_ADDRESS,
i.e. 64bit, independent on the size sent on the network.
This is required for 64bit architectures of course, but slightly overkill
on 32bit architectures, so needs fixing when all SPICE_ADDRESS elements
can be made internal.
We move all message structs from spice-protocol to spice as
we want to be able to change these as needed internally. The
on-network format is no longer defined by these structures anyway,
but rather by the spice protocol description.