[vlc-devel] [PATCH 2/7] mmdevice: follow default device changes

[Thomas Guillem]

Restart and request the new default device when it's changed by Windows and
when the "Default" virtual device is selected by VLC.

Refs #19638
---
 modules/audio_output/mmdevice.c | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/modules/audio_output/mmdevice.c b/modules/audio_output/mmdevice.c
index 48d05ad2d6..525f16ff6a 100644
--- a/modules/audio_output/mmdevice.c
+++ b/modules/audio_output/mmdevice.c
@@ -37,6 +37,7 @@ DEFINE_PROPERTYKEY(PKEY_Device_FriendlyName, 0xa45c254e, 0xdf1c, 0x4efd,
    0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 14);
 
 #include <vlc_common.h>
+#include <vlc_atomic.h>
 #include <vlc_plugin.h>
 #include <vlc_aout.h>
 #include <vlc_charset.h>
@@ -93,6 +94,7 @@ struct aout_sys_t
     float requested_volume; /**< Requested volume, negative if none */
     signed char requested_mute; /**< Requested mute, negative if none */
     wchar_t *acquired_device; /**< Acquired device identifier, NULL if none */
+    atomic_bool request_default_device;
     CRITICAL_SECTION lock;
     CONDITION_VARIABLE work;
     CONDITION_VARIABLE ready;
@@ -136,11 +138,30 @@ static int TimeGet(audio_output_t *aout, mtime_t *restrict delay)
     return SUCCEEDED(hr) ? 0 : -1;
 }
 
+static bool CheckDefaultDevice(audio_output_t *aout)
+{
+    aout_sys_t *sys = aout->sys;
+    if (!atomic_exchange(&sys->request_default_device, false))
+        return false;
+
+    if (sys->acquired_device != default_device)
+        return false;
+
+    DeviceSelect(aout, NULL);
+    return true; /* Should restart */
+}
+
 static void Play(audio_output_t *aout, block_t *block)
 {
     aout_sys_t *sys = aout->sys;
     HRESULT hr;
 
+    if (CheckDefaultDevice(aout))
+    {
+        block_Release(block);
+        return;
+    }
+
     EnterMTA();
     hr = aout_stream_Play(sys->stream, block);
     LeaveMTA();
@@ -166,6 +187,9 @@ static void Flush(audio_output_t *aout, bool wait)
     aout_sys_t *sys = aout->sys;
     HRESULT hr;
 
+    if (CheckDefaultDevice(aout))
+        return;
+
     EnterMTA();
     hr = aout_stream_Flush(sys->stream, wait);
     LeaveMTA();
@@ -571,7 +595,9 @@ vlc_MMNotificationClient_OnDefaultDeviceChange(IMMNotificationClient *this,
     if (role != eConsole)
         return S_OK;
 
-    msg_Dbg(aout, "default device changed: %ls", wid); /* TODO? migrate */
+    msg_Dbg(aout, "default device changed: %ls", wid);
+    atomic_store(&sys->request_default_device, true);
+
     return S_OK;
 }
 
@@ -1089,6 +1115,8 @@ static int Start(audio_output_t *aout, audio_sample_format_t *restrict fmt)
 {
     aout_sys_t *sys = aout->sys;
 
+    CheckDefaultDevice(aout);
+
     if (sys->dev == NULL)
         return -1;
 
@@ -1225,6 +1253,7 @@ static int Open(vlc_object_t *obj)
     sys->duck.lpVtbl = &vlc_AudioVolumeDuckNotification;
     sys->refs = 1;
     sys->ducks = 0;
+    atomic_init(&sys->request_default_device, false);
 
     sys->gain = 1.f;
     sys->requested_device = default_device;
-- 
2.11.0