-
Notifications
You must be signed in to change notification settings - Fork 23
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
This backend may integrate a bit better in desktop environments for example. It also supports instantaneous volume updates, instead of waiting around 500ms due to the ALSA buffer size. Tested on a PipeWire system, which implements the same protocol.
- Loading branch information
Showing
7 changed files
with
232 additions
and
10 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,186 @@ | ||
| package output | ||
|
|
||
| import ( | ||
| "fmt" | ||
| "io" | ||
| "sync" | ||
|
|
||
| librespot "github.com/devgianlu/go-librespot" | ||
| "github.com/jfreymuth/pulse" | ||
| "github.com/jfreymuth/pulse/proto" | ||
| log "github.com/sirupsen/logrus" | ||
| ) | ||
|
|
||
| type pulseAudioOutput struct { | ||
| sampleRate int | ||
| reader librespot.Float32Reader | ||
| client *pulse.Client | ||
| stream *pulse.PlaybackStream | ||
| volume proto.Volume | ||
| volumeLock sync.Mutex | ||
| externalVolumeUpdate chan float32 | ||
| err chan error | ||
| } | ||
|
|
||
| func newPulseAudioOutput(reader librespot.Float32Reader, sampleRate int, channels int, externalVolumeUpdate chan float32) (*pulseAudioOutput, error) { | ||
| // Initialize the PulseAudio client. | ||
| // The device name is shown by PulseAudio volume controls (usually built | ||
| // into a desktop environment), so we might want to use device_name here. | ||
| // We could also maybe change the application icon name by device_type. | ||
| client, err := pulse.NewClient(pulse.ClientApplicationName("go-librespot"), pulse.ClientApplicationIconName("speaker")) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| out := &pulseAudioOutput{ | ||
| sampleRate: sampleRate, | ||
| reader: reader, | ||
| client: client, | ||
| externalVolumeUpdate: externalVolumeUpdate, | ||
| err: make(chan error, 2), | ||
| } | ||
|
|
||
| // Create a new playback. | ||
| var channelOpt pulse.PlaybackOption | ||
| if channels == 1 { | ||
| channelOpt = pulse.PlaybackMono | ||
| } else if channels == 2 { | ||
| channelOpt = pulse.PlaybackStereo | ||
| } else { | ||
| return nil, fmt.Errorf("cannot play %d channels, pulse only supports mono and stereo", channels) | ||
| } | ||
| volumeUpdates := make(chan proto.ChannelVolumes, 1) | ||
| out.stream, err = out.client.NewPlayback(pulse.Float32Reader(out.float32Reader), pulse.PlaybackSampleRate(out.sampleRate), channelOpt, pulse.PlaybackVolumeChanges(volumeUpdates)) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
|
|
||
| // Read the initial volume from PulseAudio. | ||
| // PulseAudio strongly recommends against setting a default volume at | ||
| // startup (especially if it's 100%), so instead we just follow the | ||
| // PulseAudio provided volume. | ||
| cvol, _ := out.stream.Volume() | ||
| out.volume = cvol.Avg() | ||
| sendVolumeUpdate(externalVolumeUpdate, float32(out.volume.Norm())) | ||
|
|
||
| // Listen for volume changes (through the volume mixer application, usually | ||
| // built into the desktop environment), and send them back to Spotify. | ||
| go func() { | ||
| for cvol := range volumeUpdates { | ||
| volume := cvol.Avg() | ||
|
|
||
| out.volumeLock.Lock() | ||
| if volume != out.volume { | ||
| sendVolumeUpdate(externalVolumeUpdate, float32(volume.Norm())) | ||
| out.volume = volume | ||
| } | ||
| out.volumeLock.Unlock() | ||
| } | ||
| }() | ||
|
|
||
| return out, nil | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) float32Reader(buf []float32) (int, error) { | ||
| n, err := out.reader.Read(buf) | ||
| if err != nil { | ||
| if err == io.EOF { | ||
| // Might happen, so translate this error message. | ||
| return n, pulse.EndOfData | ||
| } | ||
|
|
||
| // Encountered another error. This will result in a stopped player, so | ||
| // send the error back to the player using a non-blocking send. | ||
| select { | ||
| case out.err <- err: | ||
| default: | ||
| } | ||
| return n, err | ||
| } | ||
| return n, err | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) Pause() error { | ||
| if out.stream.Running() { | ||
| // Stop() will stop new samples from being requested, but will continue | ||
| // to play whatever is in the buffer. | ||
| out.stream.Stop() | ||
|
|
||
| // To really stop playback *now*, we have to also flush everything | ||
| // that's in the buffer. | ||
| err := out.client.RawRequest(&proto.FlushPlaybackStream{ | ||
| StreamIndex: out.stream.StreamIndex(), | ||
| }, nil) | ||
| if err != nil { | ||
| return fmt.Errorf("Pause: could not flush playback: %e", err) | ||
| } | ||
| } else { | ||
| // Nothing to do: we're already paused. | ||
| } | ||
|
|
||
| return nil | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) Resume() error { | ||
| // Start the stream. This will start reading samples from out.reader and | ||
| // push it to PulseAudio. It will do nothing if the playback is already | ||
| // started. | ||
| out.stream.Start() | ||
| return nil | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) Drop() error { | ||
| if out.stream.Running() { | ||
| // Drop all samples while running. This happens when seeking. | ||
| // So we stop playback, flush the buffer, and restart it again to clear | ||
| // what's in the buffer. Presumably, all new samples from this point on | ||
| // are the new samples (isn't there a race condition here with | ||
| // SwitchingAudioSource?). | ||
| out.stream.Stop() | ||
| err := out.client.RawRequest(&proto.FlushPlaybackStream{ | ||
| StreamIndex: out.stream.StreamIndex(), | ||
| }, nil) | ||
| if err != nil { | ||
| return fmt.Errorf("Drop: could not flush playback: %e", err) | ||
| } | ||
| out.stream.Start() | ||
| } else { | ||
| // This sometimes happens. But we don't need to do anything: we already | ||
| // flushed the buffer in Pause(). | ||
| } | ||
| return nil | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) DelayMs() (int64, error) { | ||
| samples := out.stream.BufferSize() | ||
| delay := int64(samples) * 1000 / int64(out.sampleRate) | ||
| return delay, nil | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) SetVolume(vol float32) { | ||
| volume := proto.NormVolume(float64(vol)) | ||
|
|
||
| out.volumeLock.Lock() | ||
| if volume == out.volume { | ||
| out.volumeLock.Unlock() | ||
| return | ||
| } | ||
| out.volume = volume | ||
| sendVolumeUpdate(out.externalVolumeUpdate, vol) | ||
| out.volumeLock.Unlock() | ||
|
|
||
| cvol := proto.ChannelVolumes{volume} | ||
| err := out.stream.SetVolume(cvol) | ||
| if err != nil { | ||
| log.Warnln("failed to set volume:", err) | ||
| } | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) Error() <-chan error { | ||
| return out.err | ||
| } | ||
|
|
||
| func (out *pulseAudioOutput) Close() error { | ||
| out.stream.Close() | ||
| out.client.Close() | ||
| return nil | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters