audio: extend -audio to allow creating a default backend
If "-audio BACKEND" is used without a model, the resulting backend
will be used whenever the audiodev property is not specified.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/audio/audio.c b/audio/audio.c
index 887219e..a5e6eb4 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -1820,7 +1820,7 @@
card->state = audio_init(NULL, errp);
if (!card->state) {
if (!QSIMPLEQ_EMPTY(&audiodevs)) {
- error_append_hint(errp, "Perhaps you wanted to set audiodev=%s?\n",
+ error_append_hint(errp, "Perhaps you wanted to use -audio or set audiodev=%s?\n",
QSIMPLEQ_FIRST(&audiodevs)->dev->id);
}
return false;
diff --git a/qemu-options.hx b/qemu-options.hx
index 840b83d..54a7e94 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -728,20 +728,22 @@
DEF("audio", HAS_ARG, QEMU_OPTION_audio,
+ "-audio [driver=]driver[,prop[=value][,...]]\n"
+ " specifies default audio backend when `audiodev` is not\n"
+ " used to create a machine or sound device;"
+ " options are the same as for -audiodev\n"
"-audio [driver=]driver,model=value[,prop[=value][,...]]\n"
" specifies the audio backend and device to use;\n"
" apart from 'model', options are the same as for -audiodev.\n"
" use '-audio model=help' to show possible devices.\n",
QEMU_ARCH_ALL)
SRST
-``-audio [driver=]driver,model=value[,prop[=value][,...]]``
- This option is a shortcut for configuring both the guest audio
- hardware and the host audio backend in one go.
- The driver option is the same as with the corresponding ``-audiodev`` option below.
- The guest hardware model can be set with ``model=modelname``.
-
- Use ``driver=help`` to list the available drivers,
- and ``model=help`` to list the available device types.
+``-audio [driver=]driver[,model=value][,prop[=value][,...]]``
+ If the ``model`` option is specified, ``-audio`` is a shortcut
+ for configuring both the guest audio hardware and the host audio
+ backend in one go. The guest hardware model can be set with
+ ``model=modelname``. Use ``model=help`` to list the available
+ device types.
The following two example do exactly the same, to show how ``-audio``
can be used to shorten the command line length:
@@ -750,6 +752,17 @@
|qemu_system| -audiodev pa,id=pa -device sb16,audiodev=pa
|qemu_system| -audio pa,model=sb16
+
+ If the ``model`` option is not specified, ``-audio`` is used to
+ configure a default audio backend that will be used whenever the
+ ``audiodev`` property is not set on a device or machine. In
+ particular, ``-audio none`` ensures that no audio is produced even
+ for machines that have embedded sound hardware.
+
+ In both cases, the driver option is the same as with the corresponding
+ ``-audiodev`` option below. Use ``driver=help`` to list the available
+ drivers.
+
ERST
DEF("audiodev", HAS_ARG, QEMU_OPTION_audiodev,
diff --git a/system/vl.c b/system/vl.c
index 7ca92d4..72be5a4 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -2935,7 +2935,7 @@
break;
case QEMU_OPTION_audio: {
bool help;
- char *model;
+ char *model = NULL;
Audiodev *dev = NULL;
Visitor *v;
QDict *dict = keyval_parse(optarg, "driver", &help, &error_fatal);
@@ -2948,22 +2948,25 @@
if (!qdict_haskey(dict, "id")) {
qdict_put_str(dict, "id", "audiodev0");
}
- if (!qdict_haskey(dict, "model")) {
- error_setg(&error_fatal, "Parameter 'model' is missing");
- }
- model = g_strdup(qdict_get_str(dict, "model"));
- qdict_del(dict, "model");
- if (is_help_option(model)) {
- show_valid_soundhw();
- exit(0);
+ if (qdict_haskey(dict, "model")) {
+ model = g_strdup(qdict_get_str(dict, "model"));
+ qdict_del(dict, "model");
+ if (is_help_option(model)) {
+ show_valid_soundhw();
+ exit(0);
+ }
}
v = qobject_input_visitor_new_keyval(QOBJECT(dict));
qobject_unref(dict);
visit_type_Audiodev(v, NULL, &dev, &error_fatal);
visit_free(v);
- audio_define(dev);
- select_soundhw(model, dev->id);
- g_free(model);
+ if (model) {
+ audio_define(dev);
+ select_soundhw(model, dev->id);
+ g_free(model);
+ } else {
+ audio_define_default(dev, &error_fatal);
+ }
break;
}
case QEMU_OPTION_h:
