Add IAudioTrack::getTimestamp()

with dummy implementation in AudioFlinger::TrackHandle, and
implement AudioTrack::getTimestamp() using IAudioTrack.

Also document invariant that mAudioTrack and control block are always
non-0 after successful initialization.

Change-Id: I9861d1454cff7decf795d5d5898ac7999a9f3b7e

1 files changed, 29 insertions, 1 deletions

diff --git a/media/libmedia/IAudioTrack.cpp b/media/libmedia/IAudioTrack.cpp
index a2b49a3..f0d75ba 100644
--- a/media/libmedia/IAudioTrack.cpp
+++ b/media/libmedia/IAudioTrack.cpp
@@ -39,7 +39,8 @@ enum {
     ALLOCATE_TIMED_BUFFER,
     QUEUE_TIMED_BUFFER,
     SET_MEDIA_TIME_TRANSFORM,
-    SET_PARAMETERS
+    SET_PARAMETERS,
+    GET_TIMESTAMP,
 };
 
 class BpAudioTrack : public BpInterface<IAudioTrack>
@@ -166,6 +167,21 @@ public:
         }
         return status;
     }
+
+    virtual status_t getTimestamp(AudioTimestamp& timestamp) {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioTrack::getInterfaceDescriptor());
+        status_t status = remote()->transact(GET_TIMESTAMP, data, &reply);
+        if (status == NO_ERROR) {
+            status = reply.readInt32();
+            if (status == NO_ERROR) {
+                timestamp.mPosition = reply.readInt32();
+                timestamp.mTime.tv_sec = reply.readInt32();
+                timestamp.mTime.tv_nsec = reply.readInt32();
+            }
+        }
+        return status;
+    }
 };
 
 IMPLEMENT_META_INTERFACE(AudioTrack, "android.media.IAudioTrack");
@@ -241,6 +257,18 @@ status_t BnAudioTrack::onTransact(
             reply->writeInt32(setParameters(keyValuePairs));
             return NO_ERROR;
         } break;
+        case GET_TIMESTAMP: {
+            CHECK_INTERFACE(IAudioTrack, data, reply);
+            AudioTimestamp timestamp;
+            status_t status = getTimestamp(timestamp);
+            reply->writeInt32(status);
+            if (status == NO_ERROR) {
+                reply->writeInt32(timestamp.mPosition);
+                reply->writeInt32(timestamp.mTime.tv_sec);
+                reply->writeInt32(timestamp.mTime.tv_nsec);
+            }
+            return NO_ERROR;
+        } break;
         default:
             return BBinder::onTransact(code, data, reply, flags);
     }