audio: exit(1) if audio backend failed to be found or initialized

If you specify a known backend but it isn't compiled in, or failed to
initialize, you get a simple warning and the "none" backend as a
fallback, and QEMU runs happily:

$ qemu-system-x86_64 -audiodev id=audio,driver=dsound
audio: Unknown audio driver `dsound'
audio: warning: Using timer based audio emulation
...

Instead, QEMU should fail to start:
$ qemu-system-x86_64 -audiodev id=audio,driver=dsound
audio: Unknown audio driver `dsound'
$

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=1983493

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20220822131021.975656-1-marcandre.lureau@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/softmmu/vl.c b/softmmu/vl.c
index 706bd7c..dea4005 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -1885,7 +1885,9 @@ static void qemu_create_early_backends(void)
      * setting machine properties, so they can be referred to.
      */
     configure_blockdev(&bdo_queue, machine_class, snapshot);
-    audio_init_audiodevs();
+    if (!audio_init_audiodevs()) {
+        exit(1);
+    }
 }