Pipewire 0.3.44 introduced PW_KEY_TARGET_OBJECT, which is to be used to specify target connection nodes for streams. This parameter takes either a node path (PW_KEY_NODE_NAME) or serial number (PW_KEY_OBJECT_SERIAL) to specify a target node. The former is used in this case since the path is already being retrieved and stored for other purposes.
The target_id parameter in pw_stream_connect() is now deprecated and should always be PW_ID_ANY when PW_KEY_TARGET_OBJECT is used.
Make the default device metadata node persist for the lifetime of the hotplug loop so the default source/sink devices will be updated if they change during runtime.
With Pipewire now requiring a minimum version 0.3.24, the PW_KEY_CONTEXT_PROFILE_MODULES value is no longer required for legacy compatability and can be safely removed.
The io_list_check_add() and io_list_remove() functions are only ever called from within the Pipewire thread loop, so the locks are redundant. io_list_sort() is called from within a lock in the device detection function, so those additional locks are redundant as well.
Remove the hard upper limit of 8192 samples and instead use the buffer sizes provided by Pipewire to determine the size of the intermediate input buffer and whether double buffering is required for output streams. This allows for higher latency streams to potentially avoid double-buffering in the output case, and we can guarantee that the intermediate input buffer will always be large enough to handle whatever Pipewire may deliver.
As the buffer size calculations occur in a callback in the Pipewire processing thread itself, the stream readiness check has been modified to wait on two distinct flags set when the buffers have been configured and when the stream is ready and running.
The context and stream creation functions will destroy the passed properties object on failure, so no need to do it manually.
The pw_properties_free() function pointer is no longer needed, so it can be removed.
- use SDL_bool if possible
- assume NULL/SDL_FALSE filled impl
- skip zfill of current_audio at the beginning of SDL_AudioInit (done before the init() calls)
Pipewire, as of 0.3.22, uses client config files to load modules instead of explicitly specifying them (PW_KEY_CONTEXT_PROFILE_MODULES is deprecated). Use the new method to load the realtime module to boost the audio thread priority.
See SDL bug #4703. This implements two new hints:
- SDL_APP_NAME
- SDL_SCREENSAVER_INHIBIT_ACTIVITY_NAME
The former is the successor to SDL_HINT_AUDIO_DEVICE_APP_NAME, and acts
as a generic "application name" used both by audio drivers and DBUS
screensaver inhibition. If SDL_AUDIO_DEVICE_APP_NAME is set, it will
still take priority over SDL_APP_NAME.
The second allows the "activity name" used by
org.freedesktop.ScreenSavver's Inhibit method, which are often shown in
the UI as the reason the screensaver (and/or suspend/other
power-managment features) are disabled.
Some of the SDL_AudioDevice struct members aren't initialized until after returning from the OpenDevice function. Since Pipewire uses it's own processing threads, the callbacks can be entered before all members of SDL_AudioDevice are initialized, such as work_buffer, callbackspec and the processing stream, which creates a race condition. Don't use these members when in the paused state to avoid potentially using uninitialized values and memory.
Removes the node nickname from sink/source nodes as it doesn't provide any useful information and names now match those used in Pulseaudio, so any stored configuration data will be compatible between the two audio backends.
Constify the min/max period variables, use a #define for the base clock rate used in the calculations and note that changing the upper limit can have dire side effects as it's a hard limit in Pipewire.
Replace "magic numbers" with #defines, explain the requirements when using the userdata pointer in the node_object struct and a few other minor code and comment cleanups.
Use the 'R' (rear) prefixed designations for the rear audio channels instead of 'S' (surround). Surround designated channels are only used in the 8 channel configuration.
Further refactor the device enumeration code to retrieve the default sink/source node IDs from the metadata node. Use the retrieved IDs to sort the device list so that the default devices are at the beginning and thus are the first reported to SDL.
The latency of source nodes can change depending on the overall latency of the processing graph. Incoming audio must therefore always be buffered to ensure uninterrupted delivery.
The SDL_AudioStream path was removed in the input callback as the only thing it was used for was buffering audio outside of Pipewire's min/max period sizes, and that case is now handled by the omnipresent buffer.
Extend device enumeration to retrieve the channel count and default sample rate for sink and source nodes. This required a fairly significant rework of the enumeration procedure as multiple callbacks are involved now. Sink/source nodes are tracked in a separate list during the enumeration process so they can be cleaned up if a device is removed before completion. These changes also simplify any future efforts that may be needed to retrieve additional configuration information from the nodes.
Ozkan Sezer
Ethan Lee
Frank Praznik
Ryan C. Gordon
pionere
Sam Lantinga
David Gow
Oschowa
Frank Praznik