audio: Add functions to initialize buffers

These functions can be used to re-initialize buffers when hardware
parameters change due to device hotplug, for example.

Signed-off-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Reviewed-by: Phil Dennis-Jordan <phil@philjordan.eu>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20260304-coreaudio-v8-5-bf1d40731e73@rsg.ci.i.u-tokyo.ac.jp>

2 files changed, 20 insertions, 6 deletions

diff --git a/audio/audio-mixeng-be.c b/audio/audio-mixeng-be.c
index 5878b23e04..f7d73d8560 100644
--- a/audio/audio-mixeng-be.c
+++ b/audio/audio-mixeng-be.c
@@ -1187,14 +1187,20 @@ void audio_run(AudioMixengBackend *s, const char *msg)
     }
 }
 
+void audio_generic_initialize_buffer_in(HWVoiceIn *hw)
+{
+    g_free(hw->buf_emul);
+    hw->size_emul = hw->samples * hw->info.bytes_per_frame;
+    hw->buf_emul = g_malloc(hw->size_emul);
+    hw->pos_emul = hw->pending_emul = 0;
+}
+
 void audio_generic_run_buffer_in(HWVoiceIn *hw)
 {
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
 
     if (unlikely(!hw->buf_emul)) {
-        hw->size_emul = hw->samples * hw->info.bytes_per_frame;
-        hw->buf_emul = g_malloc(hw->size_emul);
-        hw->pos_emul = hw->pending_emul = 0;
+        audio_generic_initialize_buffer_in(hw);
     }
 
     while (hw->pending_emul < hw->size_emul) {
@@ -1227,6 +1233,14 @@ void audio_generic_put_buffer_in(HWVoiceIn *hw, void *buf, size_t size)
     hw->pending_emul -= size;
 }
 
+void audio_generic_initialize_buffer_out(HWVoiceOut *hw)
+{
+    g_free(hw->buf_emul);
+    hw->size_emul = hw->samples * hw->info.bytes_per_frame;
+    hw->buf_emul = g_malloc(hw->size_emul);
+    hw->pos_emul = hw->pending_emul = 0;
+}
+
 size_t audio_generic_buffer_get_free(HWVoiceOut *hw)
 {
     if (hw->buf_emul) {
@@ -1260,9 +1274,7 @@ void audio_generic_run_buffer_out(HWVoiceOut *hw)
 void *audio_generic_get_buffer_out(HWVoiceOut *hw, size_t *size)
 {
     if (unlikely(!hw->buf_emul)) {
-        hw->size_emul = hw->samples * hw->info.bytes_per_frame;
-        hw->buf_emul = g_malloc(hw->size_emul);
-        hw->pos_emul = hw->pending_emul = 0;
+        audio_generic_initialize_buffer_out(hw);
     }
 
     *size = MIN(hw->size_emul - hw->pending_emul,
diff --git a/audio/audio_int.h b/audio/audio_int.h
index 06f79ade6b..290cf373b4 100644
--- a/audio/audio_int.h
+++ b/audio/audio_int.h
@@ -141,9 +141,11 @@ static inline void *advance(void *p, size_t incr)
 int wav_start_capture(AudioBackend *state, CaptureState *s, const char *path,
                       int freq, int bits, int nchannels);
 
+void audio_generic_initialize_buffer_in(HWVoiceIn *hw);
 void audio_generic_run_buffer_in(HWVoiceIn *hw);
 void *audio_generic_get_buffer_in(HWVoiceIn *hw, size_t *size);
 void audio_generic_put_buffer_in(HWVoiceIn *hw, void *buf, size_t size);
+void audio_generic_initialize_buffer_out(HWVoiceOut *hw);
 void audio_generic_run_buffer_out(HWVoiceOut *hw);
 size_t audio_generic_buffer_get_free(HWVoiceOut *hw);
 void *audio_generic_get_buffer_out(HWVoiceOut *hw, size_t *size);