talk/internal/audio/check.go

package audio

import (
	"context"
	"fmt"
	"time"
)

// Check verifies that the sink name is ready without producing sound: null
// is always ready; oto initializes the audio context (default format 44.1
// kHz stereo 16 bit) and waits for it to become ready, so "no audio device"
// (servers, containers, missing PulseAudio/ALSA library) shows up in
// `talk doctor` rather than at the first announcement.
func Check(ctx context.Context, name string) error {
	switch name {
	case NameNull:
		return nil
	case NameOto:
		c, err := contextFor(pcmFormat{SampleRate: 44100, Channels: 2, BitsPerCoded: 16})
		if err != nil {
			return err
		}
		select {
		case <-c.ready:
			if err := c.ctx.Err(); err != nil {
				return fmt.Errorf("oto: initialization failed: %w", err)
			}
			return nil
		case <-ctx.Done():
			return fmt.Errorf("oto: audio device not responding (%v)", ctx.Err())
		case <-time.After(5 * time.Second):
			return fmt.Errorf("oto: audio device not responding within 5 s")
		}
	default:
		return fmt.Errorf("unknown audio sink %q (allowed: %q, %q)", name, NameOto, NameNull)
	}
}