1 files changed, 145 insertions, 0 deletions
diff --git a/quickstep/src/com/android/quickstep/util/TISBindHelper.java b/quickstep/src/com/android/quickstep/util/TISBindHelper.java
new file mode 100644
index 0000000000..7b122c6c66
--- /dev/null
+++ b/quickstep/src/com/android/quickstep/util/TISBindHelper.java
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.quickstep.util;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.os.Handler;
+import android.os.IBinder;
+import android.util.Log;
+
+import com.android.quickstep.TouchInteractionService;
+import com.android.quickstep.TouchInteractionService.TISBinder;
+
+import java.util.ArrayList;
+import java.util.function.Consumer;
+
+/**
+ * Utility class to simplify binding to {@link TouchInteractionService}
+ */
+public class TISBindHelper implements ServiceConnection {
+
+    private static final String TAG = "TISBindHelper";
+
+    private static final long BACKOFF_MILLIS = 1000;
+
+    // Max backoff caps at 5 mins
+    private static final long MAX_BACKOFF_MILLIS = 10 * 60 * 1000;
+
+    private final Handler mHandler = new Handler();
+    private final Runnable mConnectionRunnable = this::internalBindToTIS;
+    private final Context mContext;
+    private final Consumer<TISBinder> mConnectionCallback;
+    private final ArrayList<Runnable> mPendingConnectedCallbacks = new ArrayList<>();
+
+    private short mConnectionAttempts;
+    private boolean mTisServiceBound;
+    private boolean mIsConnected;
+
+    public TISBindHelper(Context context, Consumer<TISBinder> connectionCallback) {
+        mContext = context;
+        mConnectionCallback = connectionCallback;
+        internalBindToTIS();
+    }
+
+    @Override
+    public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
+        if (!(iBinder instanceof TISBinder)) {
+            // Seems like there can be a race condition when user unlocks, which kills the TIS
+            // process and re-starts it. I guess in the meantime service can be connected to
+            // a killed TIS? Either way, unbind and try to re-connect in that case.
+            internalUnbindToTIS();
+            mHandler.postDelayed(mConnectionRunnable, BACKOFF_MILLIS);
+            return;
+        }
+
+        Log.d(TAG, "TIS service connected");
+        mIsConnected = true;
+        mConnectionCallback.accept((TISBinder) iBinder);
+        // Flush the pending callbacks
+        for (Runnable r : mPendingConnectedCallbacks) {
+            r.run();
+        }
+        mPendingConnectedCallbacks.clear();
+        resetServiceBindRetryState();
+    }
+
+    @Override
+    public void onServiceDisconnected(ComponentName componentName) { }
+
+    @Override
+    public void onBindingDied(ComponentName name) {
+        Log.w(TAG, "TIS binding died");
+        internalBindToTIS();
+    }
+
+    /**
+     * Runs the given {@param r} runnable when the service is connected.
+     */
+    public void runOnBindToTouchInteractionService(Runnable r) {
+        if (mIsConnected) {
+            r.run();
+        } else {
+            mPendingConnectedCallbacks.add(r);
+        }
+    }
+
+    /**
+     * Binds to {@link TouchInteractionService}. If the binding fails, attempts to retry via
+     * {@link #mConnectionRunnable}. Unbind via {@link #internalUnbindToTIS()}
+     */
+    private void internalBindToTIS() {
+        mTisServiceBound = mContext.bindService(new Intent(mContext, TouchInteractionService.class),
+                this, 0);
+        if (mTisServiceBound) {
+            resetServiceBindRetryState();
+            return;
+        }
+
+        Log.w(TAG, "Retrying TIS Binder connection attempt: " + mConnectionAttempts);
+        final long timeoutMs = (long) Math.min(
+                Math.scalb(BACKOFF_MILLIS, mConnectionAttempts), MAX_BACKOFF_MILLIS);
+        mHandler.postDelayed(mConnectionRunnable, timeoutMs);
+        mConnectionAttempts++;
+    }
+
+    /** See {@link #internalBindToTIS()} */
+    private void internalUnbindToTIS() {
+        if (mTisServiceBound) {
+            mContext.unbindService(this);
+            mTisServiceBound = false;
+        }
+    }
+
+    private void resetServiceBindRetryState() {
+        if (mHandler.hasCallbacks(mConnectionRunnable)) {
+            mHandler.removeCallbacks(mConnectionRunnable);
+        }
+        mConnectionAttempts = 0;
+    }
+
+    /**
+     * Called when the activity is destroyed to clear the binding
+     */
+    public void onDestroy() {
+        internalUnbindToTIS();
+        resetServiceBindRetryState();
+        mIsConnected = false;
+        mPendingConnectedCallbacks.clear();
+    }
+}