audio: constify some add_capture() arguments

Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

audio/audio-be.c

@@ -182,8 +182,8 @@ void audio_be_set_volume_in(AudioBackend *be, SWVoiceIn *sw, Volume *vol)
 
 CaptureVoiceOut *audio_be_add_capture(
     AudioBackend *be,
-    struct audsettings *as,
-    struct audio_capture_ops *ops,
+    const struct audsettings *as,
+    const struct audio_capture_ops *ops,
     void *cb_opaque)
 {
     AudioBackendClass *klass = AUDIO_BACKEND_GET_CLASS(be);

audio/audio-mixeng-be.c

@@ -314,7 +314,7 @@ void audio_pcm_info_clear_buf (struct audio_pcm_info *info, void *buf, int len)
  * Capture
  */
 static CaptureVoiceOut *audio_pcm_capture_find_specific(AudioMixengBackend *s,
-                                                        struct audsettings *as)
+                                                        const struct audsettings *as)
 {
     CaptureVoiceOut *cap;
 
@@ -1585,8 +1585,8 @@ static const char *audio_mixeng_backend_get_id(AudioBackend *be)
 
 static CaptureVoiceOut *audio_mixeng_backend_add_capture(
     AudioBackend *be,
-    struct audsettings *as,
-    struct audio_capture_ops *ops,
+    const struct audsettings *as,
+    const struct audio_capture_ops *ops,
     void *cb_opaque);
 
 static void audio_mixeng_backend_del_capture(
@@ -1710,8 +1710,8 @@ static const VMStateDescription vmstate_audio = {
 
 static CaptureVoiceOut *audio_mixeng_backend_add_capture(
     AudioBackend *be,
-    struct audsettings *as,
-    struct audio_capture_ops *ops,
+    const struct audsettings *as,
+    const struct audio_capture_ops *ops,
     void *cb_opaque)
 {
     AudioMixengBackend *s = AUDIO_MIXENG_BACKEND(be);

include/qemu/audio-capture.h

@@ -21,8 +21,8 @@ typedef struct CaptureState {
 
 CaptureVoiceOut *audio_be_add_capture(
     AudioBackend *be,
-    struct audsettings *as,
-    struct audio_capture_ops *ops,
+    const struct audsettings *as,
+    const struct audio_capture_ops *ops,
     void *opaque);
 
 void audio_be_del_capture(

include/qemu/audio.h

@@ -96,8 +96,8 @@ typedef struct AudioBackendClass {
     size_t (*read)(AudioBackend *be, SWVoiceIn *sw, void *buf, size_t size);
     int (*get_buffer_size_out)(AudioBackend *be, SWVoiceOut *sw);
     CaptureVoiceOut *(*add_capture)(AudioBackend *be,
-                                    struct audsettings *as,
-                                    struct audio_capture_ops *ops,
+                                    const struct audsettings *as,
+                                    const struct audio_capture_ops *ops,
                                     void *cb_opaque);
     void (*del_capture)(AudioBackend *be, CaptureVoiceOut *cap, void *cb_opaque);