AudioTrack: Improve pause handling.
Add pauseAndWait() method to ensure that the pause is completed
(ramped to silence) before any other operation, especially flush().
Incorporate into MediaPlayer pause().
Test: Clarity video with scrubbing bar.
Test: Ringtone and Alarm playback.
Bug: 196194083
Change-Id: Id8842c6c8abfd76d11b8316a95052c2e0da7fb7c
diff --git a/media/libaudioclient/AudioTrack.cpp b/media/libaudioclient/AudioTrack.cpp
index 5f802de..3bc666b 100644
--- a/media/libaudioclient/AudioTrack.cpp
+++ b/media/libaudioclient/AudioTrack.cpp
@@ -21,6 +21,7 @@
#include <inttypes.h>
#include <math.h>
#include <sys/resource.h>
+#include <thread>
#include <android/media/IAudioPolicyService.h>
#include <android-base/macros.h>
@@ -947,6 +948,44 @@
mAudioTrack->flush();
}
+bool AudioTrack::pauseAndWait(const std::chrono::milliseconds& timeout)
+{
+ using namespace std::chrono_literals;
+
+ pause();
+
+ AutoMutex lock(mLock);
+ // offload and direct tracks do not wait because pause volume ramp is handled by hardware.
+ if (isOffloadedOrDirect_l()) return true;
+
+ // Wait for the track state to be anything besides pausing.
+ // This ensures that the volume has ramped down.
+ constexpr auto SLEEP_INTERVAL_MS = 10ms;
+ auto begin = std::chrono::steady_clock::now();
+ while (true) {
+ // wait for state to change
+ const int state = mProxy->getState();
+
+ mLock.unlock(); // only local variables accessed until lock.
+ auto elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(
+ std::chrono::steady_clock::now() - begin);
+ if (state != CBLK_STATE_PAUSING) {
+ ALOGV("%s: success state:%d after %lld ms", __func__, state, elapsed.count());
+ return true;
+ }
+ std::chrono::milliseconds remaining = timeout - elapsed;
+ if (remaining.count() <= 0) {
+ ALOGW("%s: timeout expired state:%d still pausing:%d after %lld ms",
+ __func__, state, CBLK_STATE_PAUSING, elapsed.count());
+ return false;
+ }
+ // It is conceivable that the track is restored while sleeping;
+ // as this logic is advisory, we allow that.
+ std::this_thread::sleep_for(std::min(remaining, SLEEP_INTERVAL_MS));
+ mLock.lock();
+ }
+}
+
void AudioTrack::pause()
{
const int64_t beginNs = systemTime();