1 files changed, 78 insertions, 0 deletions
diff --git a/core/java/android/net/TcpSocketKeepalive.java b/core/java/android/net/TcpSocketKeepalive.java
new file mode 100644
index 000000000000..8f6ee7bf2950
--- /dev/null
+++ b/core/java/android/net/TcpSocketKeepalive.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2019 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 android.net;
+
+import android.annotation.NonNull;
+import android.os.Binder;
+import android.os.RemoteException;
+import android.util.Log;
+
+import java.io.FileDescriptor;
+import java.net.Socket;
+import java.util.concurrent.Executor;
+
+/** @hide */
+final class TcpSocketKeepalive extends SocketKeepalive {
+
+    private final Socket mSocket;
+
+    TcpSocketKeepalive(@NonNull IConnectivityManager service,
+            @NonNull Network network,
+            @NonNull Socket socket,
+            @NonNull Executor executor,
+            @NonNull Callback callback) {
+        super(service, network, executor, callback);
+        mSocket = socket;
+    }
+
+    /**
+     * Starts keepalives. {@code mSocket} must be a connected TCP socket.
+     *
+     * - The application must not write to or read from the socket after calling this method, until
+     *   onDataReceived, onStopped, or onError are called. If it does, the keepalive will fail
+     *   with {@link #ERROR_SOCKET_NOT_IDLE}, or {@code #ERROR_INVALID_SOCKET} if the socket
+     *   experienced an error (as in poll(2) returned POLLERR); if this happens, the data received
+     *   from the socket may be invalid, and the socket can't be recovered.
+     * - If the socket has data in the send or receive buffer, then this call will fail with
+     *   {@link #ERROR_SOCKET_NOT_IDLE} and can be retried after the data has been processed.
+     *   An app could ensure this by using an application-layer protocol where it can receive
+     *   acknowledgement that it will go into keepalive mode. It could then go into keepalive
+     *   mode after having read the acknowledgement, draining the socket.
+     */
+    @Override
+    void startImpl(int intervalSec) {
+        try {
+            final FileDescriptor fd = mSocket.getFileDescriptor$();
+            mService.startTcpKeepalive(mNetwork, fd, intervalSec, mMessenger, new Binder());
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error starting packet keepalive: ", e);
+            stopLooper();
+        }
+    }
+
+    @Override
+    void stopImpl() {
+        try {
+            if (mSlot != null) {
+                mService.stopKeepalive(mNetwork, mSlot);
+            }
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error stopping packet keepalive: ", e);
+            stopLooper();
+        }
+    }
+}