From f57201989b82e683e0d437747b7318c3e24fe0d3 Mon Sep 17 00:00:00 2001
From: Samuel Ortiz <sameo@linux.intel.com>
Date: Fri, 9 Sep 2016 18:45:31 +0200
Subject: [PATCH] qemu: Use null QMP logger when the logger parameter is nil

Or else LaunchQemu() ends up dereferencing a nil pointer and panic'ing.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
---
 qemu.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/qemu.go b/qemu.go
index 88af0217b..6014d36a9 100644
--- a/qemu.go
+++ b/qemu.go
@@ -49,6 +49,10 @@ import (
 // will be returned if the launch succeeds.  Otherwise a string containing
 // the contents of stderr + a Go error object will be returned.
 func LaunchQemu(ctx context.Context, params []string, fds []*os.File, logger QMPLog) (string, error) {
+	if logger == nil {
+		logger = qmpNullLogger{}
+	}
+
 	errStr := ""
 	cmd := exec.Command("qemu-system-x86_64", params...)
 	if len(fds) > 0 {