ao/wasapi: make get_device_delay return an error code

1 files changed, 21 insertions, 12 deletions

diff --git a/audio/out/ao_wasapi.c b/audio/out/ao_wasapi.c
index b328fd61b2..dd862d27b7 100644
--- a/audio/out/ao_wasapi.c
+++ b/audio/out/ao_wasapi.c
@@ -36,18 +36,19 @@
 #include "osdep/timer.h"
 #include "osdep/io.h"
 
-static double get_device_delay(struct wasapi_state *state) {
+static HRESULT get_device_delay(struct wasapi_state *state, double *delay) {
     UINT64 sample_count = atomic_load(&state->sample_count);
     UINT64 position, qpc_position;
     HRESULT hr;
 
-    switch (hr = IAudioClock_GetPosition(state->pAudioClock, &position, &qpc_position)) {
-        case S_OK: case S_FALSE:
-            break;
-        default:
-            MP_ERR(state, "IAudioClock::GetPosition returned %s (0x%"PRIx32")\n",
-                   wasapi_explain_err(hr), (uint32_t)hr);
+    hr = IAudioClock_GetPosition(state->pAudioClock, &position, &qpc_position);
+    /* GetPosition succeeded, but the result may be inaccurate due to the length of the call */
+    /* http://msdn.microsoft.com/en-us/library/windows/desktop/dd370889%28v=vs.85%29.aspx */
+    if ( hr == S_FALSE) {
+        MP_DBG(state, "Possibly inaccurate device position.\n");
+        hr = S_OK;
     }
+    EXIT_ON_ERROR(hr);
 
     LARGE_INTEGER qpc_count;
     QueryPerformanceCounter(&qpc_count);
@@ -59,11 +60,15 @@ static double get_device_delay(struct wasapi_state *state) {
     position = position * state->format.Format.nSamplesPerSec / state->clock_frequency;
 
     double diff = sample_count - position;
-    double delay = diff / state->format.Format.nSamplesPerSec;
+    *delay = diff / state->format.Format.nSamplesPerSec;
 
-    MP_TRACE(state, "Device delay: %g samples (%g ms)\n", diff, delay * 1000);
+    MP_TRACE(state, "Device delay: %g samples (%g ms)\n", diff, *delay * 1000);
 
-    return delay;
+    return S_OK;
+exit_label:
+    MP_ERR(state, "Error getting device delay: %s (0x%"PRIx32")\n",
+           wasapi_explain_err(hr), (uint32_t)hr);
+    return hr;
 }
 
 static void thread_feed(struct ao *ao)
@@ -81,6 +86,9 @@ static void thread_feed(struct ao *ao)
         frame_count -= padding;
         MP_TRACE(ao, "Frame to fill: %"PRIu32". Padding: %"PRIu32"\n", frame_count, padding);
     }
+    double delay;
+    hr = get_device_delay(state, &delay);
+    EXIT_ON_ERROR(hr);
 
     BYTE *pData;
     hr = IAudioRenderClient_GetBuffer(state->pRenderClient,
@@ -88,9 +96,10 @@ static void thread_feed(struct ao *ao)
     EXIT_ON_ERROR(hr);
 
     BYTE *data[1] = {pData};
+
     ao_read_data(ao, (void**)data, frame_count, (int64_t) (
-                 mp_time_us() + get_device_delay(state) * 1e6 +
-                 frame_count * 1e6 / state->format.Format.nSamplesPerSec));
+                     mp_time_us() + delay * 1e6 +
+                     frame_count * 1e6 / state->format.Format.nSamplesPerSec));
 
     hr = IAudioRenderClient_ReleaseBuffer(state->pRenderClient,
                                           frame_count, 0);