aaudio: refactor references to shared FIFO

Reduce passing of raw pointers.
Use shared_ptrs and unique_ptrs.
Simplify memory management.

Refactor FifoBuffer into two subclasses so that
the internal memory management is simpler.

Bug: 151650670
Test: OboeTester "TEST OUTPUT"
Test: disable EXCLUSIVE mode
Test: OboeTester "ECHO INPUT TO OUTPUT"
Test: disable INPUT EXCLUSIVE mode
Change-Id: I10981767f8719f3cc3525df211285c53219a7979
diff --git a/services/oboeservice/AAudioServiceStreamShared.cpp b/services/oboeservice/AAudioServiceStreamShared.cpp
index f2cf016..e88a81e 100644
--- a/services/oboeservice/AAudioServiceStreamShared.cpp
+++ b/services/oboeservice/AAudioServiceStreamShared.cpp
@@ -59,12 +59,7 @@
 
     result << AAudioServiceStreamBase::dump();
 
-    auto fifo = mAudioDataQueue->getFifoBuffer();
-    int32_t readCounter = fifo->getReadCounter();
-    int32_t writeCounter = fifo->getWriteCounter();
-    result << std::setw(10) << writeCounter;
-    result << std::setw(10) << readCounter;
-    result << std::setw(8) << (writeCounter - readCounter);
+    result << mAudioDataQueue->dump();
     result << std::setw(8) << getXRunCount();
 
     return result.str();
@@ -180,7 +175,7 @@
     {
         std::lock_guard<std::mutex> lock(mAudioDataQueueLock);
         // Create audio data shared memory buffer for client.
-        mAudioDataQueue = new SharedRingBuffer();
+        mAudioDataQueue = std::make_shared<SharedRingBuffer>();
         result = mAudioDataQueue->allocate(calculateBytesPerFrame(), getBufferCapacity());
         if (result != AAUDIO_OK) {
             ALOGE("%s() could not allocate FIFO with %d frames",
@@ -203,18 +198,6 @@
     return result;
 }
 
-aaudio_result_t AAudioServiceStreamShared::close_l()  {
-    aaudio_result_t result = AAudioServiceStreamBase::close_l();
-
-    {
-        std::lock_guard<std::mutex> lock(mAudioDataQueueLock);
-        delete mAudioDataQueue;
-        mAudioDataQueue = nullptr;
-    }
-
-    return result;
-}
-
 /**
  * Get an immutable description of the data queue created by this service.
  */
@@ -273,3 +256,37 @@
     *positionFrames = position;
     return result;
 }
+
+void AAudioServiceStreamShared::writeDataIfRoom(int64_t mmapFramesRead,
+                                                const void *buffer, int32_t numFrames) {
+    int64_t clientFramesWritten = 0;
+
+    // Lock the AudioFifo to protect against close.
+    std::lock_guard <std::mutex> lock(mAudioDataQueueLock);
+
+    if (mAudioDataQueue != nullptr) {
+        std::shared_ptr<FifoBuffer> fifo = mAudioDataQueue->getFifoBuffer();
+        // Determine offset between framePosition in client's stream
+        // vs the underlying MMAP stream.
+        clientFramesWritten = fifo->getWriteCounter();
+        // There are two indices that refer to the same frame.
+        int64_t positionOffset = mmapFramesRead - clientFramesWritten;
+        setTimestampPositionOffset(positionOffset);
+
+        // Is the buffer too full to write a burst?
+        if (fifo->getEmptyFramesAvailable() < getFramesPerBurst()) {
+            incrementXRunCount();
+        } else {
+            fifo->write(buffer, numFrames);
+        }
+        clientFramesWritten = fifo->getWriteCounter();
+    }
+
+    if (clientFramesWritten > 0) {
+        // This timestamp represents the completion of data being written into the
+        // client buffer. It is sent to the client and used in the timing model
+        // to decide when data will be available to read.
+        Timestamp timestamp(clientFramesWritten, AudioClock::getNanoseconds());
+        markTransferTime(timestamp);
+    }
+}