Replace size_t in shared memory by uint32_t

Eventually we may want to use uint64_t, but will need to confirm atomicity.

Bug: 12381724
Change-Id: Ia2c591d262d22b47b6f7dab4b9d9faa14b86d865

2 files changed, 18 insertions, 6 deletions

diff --git a/include/private/media/AudioTrackShared.h b/include/private/media/AudioTrackShared.h
index b5a4c0b..3901e79 100644
--- a/include/private/media/AudioTrackShared.h
+++ b/include/private/media/AudioTrackShared.h
@@ -65,7 +65,9 @@ typedef SingleStateQueue<StaticAudioTrackState> StaticAudioTrackSingleStateQueue
 struct AudioTrackSharedStatic {
     StaticAudioTrackSingleStateQueue::Shared
                     mSingleStateQueue;
-    size_t          mBufferPosition;    // updated asynchronously by server,
+    // This field should be a size_t, but since it is located in shared memory we
+    // force to 32-bit.  The client and server may have different typedefs for size_t.
+    uint32_t        mBufferPosition;    // updated asynchronously by server,
                                         // "for entertainment purposes only"
 };
 
@@ -104,7 +106,9 @@ struct audio_track_cblk_t
 
 private:
 
-                size_t      mMinimum;       // server wakes up client if available >= mMinimum
+                // This field should be a size_t, but since it is located in shared memory we
+                // force to 32-bit.  The client and server may have different typedefs for size_t.
+                uint32_t    mMinimum;       // server wakes up client if available >= mMinimum
 
                 // Channel volumes are fixed point U4.12, so 0x1000 means 1.0.
                 // Left channel is in [0:15], right channel is in [16:31].
@@ -241,7 +245,11 @@ public:
     }
 
     void        setMinimum(size_t minimum) {
-        mCblk->mMinimum = minimum;
+        // This can only happen on a 64-bit client
+        if (minimum > UINT32_MAX) {
+            minimum = UINT32_MAX;
+        }
+        mCblk->mMinimum = (uint32_t) minimum;
     }
 
     // Return the number of frames that would need to be obtained and released
diff --git a/include/private/media/StaticAudioTrackState.h b/include/private/media/StaticAudioTrackState.h
index 46a5946..d483061 100644
--- a/include/private/media/StaticAudioTrackState.h
+++ b/include/private/media/StaticAudioTrackState.h
@@ -25,9 +25,13 @@ namespace android {
 // state is wrapped by a SingleStateQueue.
 struct StaticAudioTrackState {
     // do not define constructors, destructors, or virtual methods
-    size_t  mLoopStart;
-    size_t  mLoopEnd;
-    int     mLoopCount;
+
+    // These fields should both be size_t, but since they are located in shared memory we
+    // force to 32-bit.  The client and server may have different typedefs for size_t.
+    uint32_t    mLoopStart;
+    uint32_t    mLoopEnd;
+
+    int         mLoopCount;
 };
 
 }   // namespace android