radiodiodio/audio/audio.go

package audio

import (
	"fmt"
	"os"
	"os/signal"
	"time"
	"../icecast"
)

type Next func() (string, error)

func Start(next_cb Next)  {

	sig := make(chan os.Signal, 1)
	signal.Notify(sig, os.Interrupt, os.Kill)	

	samplerate := 44100
	bytes_per_sample := 1
	channels := 1
	bytes_per_sec := int(samplerate) * channels * bytes_per_sample

	_, er := icecast.Connect()
	chk(er)

	audio := make([]byte, 2 * 1024)
	dt := time.Second * time.Duration(len(audio)) / time.Duration(bytes_per_sec)

	for fname, exit := next_cb(); exit == nil; fname, exit = next_cb() {

		r, e := os.Open(fname)
		chk(e)
		defer r.Close()

		now := time.Now()

		for {

			n, err := r.Read(audio)
			if n == 0 {
				break
			}
			chk(err)

			pre := time.Now()

			icecast.Send(audio)

			post := time.Now()
			lag := time.Duration((post.Sub(pre)))

			select {
				case <-sig:
					return
				default:
			}

			dt = (time.Second * time.Duration(n) / time.Duration(bytes_per_sec)) - lag
			
			time.Sleep(dt)		

		}

		fmt.Println(time.Duration(time.Now().Sub(now)))

	}

}


func chk(err error) {
	if err != nil {
		panic(err)
	}
}