From 6d9c9dcb5b81c0fa7fc1a2efd12a8f3c0b278a08 Mon Sep 17 00:00:00 2001
From: Robert Wu <robertwu@google.com>
Date: Thu, 10 Mar 2022 23:09:47 +0000
Subject: [PATCH] BluetoothMidi: Remove unsafe code

In ag/16192242, several functions in Bluetooth relating to
characteristics were marked as unsafe and new ones were added.

This CL is meant to conform with these standards and potentially
remove a long standing bug.

Bug: 146385555
Test: Added Identity Reply/Request code to MIDIMatrix
and tested with Yamaha MD-BT01 for Android T->T, T->R, R->T
Change-Id: I07311296509d4d042fc92aec327f40993d2e6f54
---
 .../BluetoothMidiDevice.java                  | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
index 4c3b68958c0f..0e6249047980 100644
--- a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
+++ b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
@@ -150,6 +150,7 @@ public final class BluetoothMidiDevice {
         @Override
         public void onCharacteristicRead(BluetoothGatt gatt,
                 BluetoothGattCharacteristic characteristic,
+                byte[] value,
                 int status) {
             Log.d(TAG, "onCharacteristicRead " + status);
 
@@ -164,8 +165,8 @@ public final class BluetoothMidiDevice {
             BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
                     CLIENT_CHARACTERISTIC_CONFIG);
             if (descriptor != null) {
-                descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
-                boolean result = mBluetoothGatt.writeDescriptor(descriptor);
+                int result = mBluetoothGatt.writeDescriptor(descriptor,
+                        BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
                 Log.d(TAG, "writeDescriptor returned " + result);
             } else {
                 Log.e(TAG, "No CLIENT_CHARACTERISTIC_CONFIG for device " + mBluetoothDevice);
@@ -184,12 +185,13 @@ public final class BluetoothMidiDevice {
 
         @Override
         public void onCharacteristicChanged(BluetoothGatt gatt,
-                                            BluetoothGattCharacteristic characteristic) {
+                                            BluetoothGattCharacteristic characteristic,
+                                            byte[] value) {
             if (DEBUG) {
-                logByteArray("Received ", characteristic.getValue(), 0,
-                        characteristic.getValue().length);
+                logByteArray("Received BLE packet", value, 0,
+                        value.length);
             }
-            mPacketDecoder.decodePacket(characteristic.getValue(), mOutputReceiver);
+            mPacketDecoder.decodePacket(value, mOutputReceiver);
         }
 
         @Override
@@ -227,17 +229,14 @@ public final class BluetoothMidiDevice {
                 mCachedBuffer = new byte[count];
             }
             System.arraycopy(buffer, 0, mCachedBuffer, 0, count);
-            if (!mCharacteristic.setValue(mCachedBuffer)) {
-                Log.w(TAG, "could not set characteristic value");
-                return false;
-            }
 
             if (DEBUG) {
                 logByteArray("Sent ", mCharacteristic.getValue(), 0,
                        mCharacteristic.getValue().length);
             }
 
-            if (!mBluetoothGatt.writeCharacteristic(mCharacteristic)) {
+            if (mBluetoothGatt.writeCharacteristic(mCharacteristic, mCachedBuffer,
+                    mCharacteristic.getWriteType()) != BluetoothGatt.GATT_SUCCESS) {
                 Log.w(TAG, "could not write characteristic to Bluetooth GATT");
                 return false;
             }