add audio support, trying to manage MSD device

http/hw/stream/extprocess.go

@@ -4,6 +4,7 @@ import (
 	"io"
 	"os"
 	"os/exec"
+	"rkkvm/config"
 	"sync"
 
 	log "github.com/sirupsen/logrus"
@@ -25,7 +26,7 @@ type ExtProcess struct {
 func Init(path string, args []string) *ExtProcess {
 	return &ExtProcess{
 		args: args,
-		path: path,
+		path: config.RootFS + path,
 	}
 }
 
@@ -41,7 +42,7 @@ func (u *ExtProcess) Start() {
 	u.stopChan = make(chan struct{})
 	u.finished = make(chan struct{})
 
-	log.Debug("Starting external process...")
+	log.Debugf("Starting external process: %s %v", u.path, u.args)
 	u.cmd = exec.Command(u.path, u.args...)
 	u.cmd.Stdout = os.Stdout
 	u.cmd.Stderr = os.Stderr
@@ -99,8 +100,6 @@ func (u *ExtProcess) Stop() {
 		log.Errorf("Failed to close stdin: %v", err)
 	}
 
-	log.Info("waiting for finish")
-
 	select {
 	case <-u.finished:
 		log.Info("stopped as expected")