The sound and microphone redirection channels (and in part TSMF)
did not properly decouple encoding/decoding from the backends used
to play/record sound.
Encapsulating encoding/decoding in rewritten freerdp_dsp_* functions
with variable backends, simplifying alsa/oss/pulse/... audio backends.
- fixed invalid, missing or additional arguments
- removed all type casts from arguments
- added missing (void*) typecasts for %p arguments
- use inttypes defines where appropriate
It will be completely possible to implement subsystem with only include/freerdp/server/shadow.h and libfreerdp-shadow.
Details as following:
1. Exported surface structure as subsystem implementations deeply depend on it to send image update
2. Export capture APIs. They are actually indepent APIs to help compare and calculate image difference.
3. Introduce API to trigger client frame update. Conceal details in subsystem->updateEvent
4. Pass client to client callbacks. Subsystem implementation may need to know 'which client' send the interaction event as well as the authentication request.
Add this support in callback definition before anyone really use shadow framework APIs to implement a custom subsystem.
Also added callback for client capability exchange
5. Remove X11_ShadowSubsystem Mac_ShadowSubsystem Win_ShadowSubsystem from libfreerdp-shadow.
Discard FREERDP_API mark on ShadowSubsystemEntry functions and make them be compiled together with shadow.c in CMakeLists.txt.
This is required from PR #2751.
Now subsystem implementations and shadow.c could be regarded as an example for shadow framework.
1. Introduce message queue in shadow client. No longer use subsytem->MsgPipe->out to deliver message to clients.
We used to use subsytem->MsgPipe->out for messages which need to be sent to client. But it's not correct. Only one client would get the message if multiple client exists
This problem make the fix in PR #2643 incomplete.
Introduced reference count based solution to release resource taken by the message.
Also added APIs for client message delivery.
Also fixed msg pipe in subsystem to clean resource when destroyed.
2. Discard unused StopEvent in client. We actually use quit message instead.
3. Enhance disposal of channels.
Free context for remdesk and encomsp channels. The original fix only stop the threads, but doesn't release resource.
Dispose channels earlier. The channels are built on client->vcm. Disposing channels after client->vcm is closed cause unknown behavior.
Original fix is #2644
4. Start to add audio support.
