Merged in alsa-pool (pull request #471)

alsa: handle pool buffer error and properly close chunks

Approved-by: Saxon Milton

device/alsa/alsa.go

@@ -30,6 +30,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"io"
 	"sync"
 	"time"
 
@@ -405,7 +406,6 @@ func (d *ALSA) input() {
 			d.l.Log(logger.Warning, "old audio data overwritten")
 		default:
 			d.l.Log(logger.Error, "unexpected ringbuffer error", "error", err.Error())
-			return
 		}
 	}
 }
@@ -413,13 +413,37 @@ func (d *ALSA) input() {
 // Read reads from the ringbuffer, returning the number of bytes read upon success.
 func (d *ALSA) Read(p []byte) (int, error) {
 	// Ready ringbuffer for read.
+	d.l.Log(logger.Debug, pkg+"getting next chunk ready")
 	_, err := d.buf.Next(rbNextTimeout)
 	if err != nil {
-		return 0, err
+		switch err {
+		case nil, io.EOF:
+			d.l.Log(logger.Debug, pkg+"EOF")
+			return 0, nil
+		case pool.ErrTimeout:
+			d.l.Log(logger.Debug, pkg+"pool buffer timeout")
+			return 0, nil
+		default:
+			d.l.Log(logger.Error, pkg+"unexpected error from Next", "error", err.Error())
+			return 0, nil
+		}
 	}
 
 	// Read from pool buffer.
-	return d.buf.Read(p)
+	d.l.Log(logger.Debug, pkg+"reading from buffer")
+	n, err := d.buf.Read(p)
+	if err != nil {
+		switch err {
+		case nil, io.EOF:
+			d.l.Log(logger.Debug, pkg+"EOF from Read, stopping")
+			return n, err
+		default:
+			d.l.Log(logger.Error, pkg+"unexpected error from Read", "error", err.Error())
+			return n, nil
+		}
+	}
+	d.l.Log(logger.Debug, fmt.Sprintf("%v read %v bytes", pkg, n))
+	return n, nil
 }
 
 // formatBuffer returns audio that has been converted to the desired format.