Move module sources to packages/Connectivity

Files that are planned to be part of the connectivity module are grouped
in packages/Connectivity, so they can be built separately and moved in
one operation with their history into packages/modules/Connectivity.

This places the files in the existing framework-connectivity-sources
filegroup instead of the current framework-core-sources filegroup. Both
are used the same way in framework-non-updatable-sources.

Bug: 171540887
Test: m
Change-Id: I62d9d91574ace6f5c4624035d190260c3126b91e
diff --git a/framework/src/android/net/SocketKeepalive.java b/framework/src/android/net/SocketKeepalive.java
new file mode 100644
index 0000000..d007a95
--- /dev/null
+++ b/framework/src/android/net/SocketKeepalive.java
@@ -0,0 +1,301 @@
+/*
+ * 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.IntDef;
+import android.annotation.IntRange;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.os.Binder;
+import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
+
+import java.io.IOException;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.concurrent.Executor;
+
+/**
+ * Allows applications to request that the system periodically send specific packets on their
+ * behalf, using hardware offload to save battery power.
+ *
+ * To request that the system send keepalives, call one of the methods that return a
+ * {@link SocketKeepalive} object, such as {@link ConnectivityManager#createSocketKeepalive},
+ * passing in a non-null callback. If the {@link SocketKeepalive} is successfully
+ * started, the callback's {@code onStarted} method will be called. If an error occurs,
+ * {@code onError} will be called, specifying one of the {@code ERROR_*} constants in this
+ * class.
+ *
+ * To stop an existing keepalive, call {@link SocketKeepalive#stop}. The system will call
+ * {@link SocketKeepalive.Callback#onStopped} if the operation was successful or
+ * {@link SocketKeepalive.Callback#onError} if an error occurred.
+ *
+ * For cellular, the device MUST support at least 1 keepalive slot.
+ *
+ * For WiFi, the device SHOULD support keepalive offload. If it does not, it MUST reply with
+ * {@link SocketKeepalive.Callback#onError} with {@code ERROR_UNSUPPORTED} to any keepalive offload
+ * request. If it does, it MUST support at least 3 concurrent keepalive slots.
+ */
+public abstract class SocketKeepalive implements AutoCloseable {
+    static final String TAG = "SocketKeepalive";
+
+    /**
+     * No errors.
+     * @hide
+     */
+    @SystemApi
+    public static final int SUCCESS = 0;
+
+    /** @hide */
+    public static final int NO_KEEPALIVE = -1;
+
+    /** @hide */
+    public static final int DATA_RECEIVED = -2;
+
+    /** @hide */
+    public static final int BINDER_DIED = -10;
+
+    /** The specified {@code Network} is not connected. */
+    public static final int ERROR_INVALID_NETWORK = -20;
+    /** The specified IP addresses are invalid. For example, the specified source IP address is
+     * not configured on the specified {@code Network}. */
+    public static final int ERROR_INVALID_IP_ADDRESS = -21;
+    /** The requested port is invalid. */
+    public static final int ERROR_INVALID_PORT = -22;
+    /** The packet length is invalid (e.g., too long). */
+    public static final int ERROR_INVALID_LENGTH = -23;
+    /** The packet transmission interval is invalid (e.g., too short). */
+    public static final int ERROR_INVALID_INTERVAL = -24;
+    /** The target socket is invalid. */
+    public static final int ERROR_INVALID_SOCKET = -25;
+    /** The target socket is not idle. */
+    public static final int ERROR_SOCKET_NOT_IDLE = -26;
+    /**
+     * The stop reason is uninitialized. This should only be internally used as initial state
+     * of stop reason, instead of propagating to application.
+     * @hide
+     */
+    public static final int ERROR_STOP_REASON_UNINITIALIZED = -27;
+
+    /** The device does not support this request. */
+    public static final int ERROR_UNSUPPORTED = -30;
+    /** @hide TODO: delete when telephony code has been updated. */
+    public static final int ERROR_HARDWARE_UNSUPPORTED = ERROR_UNSUPPORTED;
+    /** The hardware returned an error. */
+    public static final int ERROR_HARDWARE_ERROR = -31;
+    /** The limitation of resource is reached. */
+    public static final int ERROR_INSUFFICIENT_RESOURCES = -32;
+
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "ERROR_" }, value = {
+            ERROR_INVALID_NETWORK,
+            ERROR_INVALID_IP_ADDRESS,
+            ERROR_INVALID_PORT,
+            ERROR_INVALID_LENGTH,
+            ERROR_INVALID_INTERVAL,
+            ERROR_INVALID_SOCKET,
+            ERROR_SOCKET_NOT_IDLE
+    })
+    public @interface ErrorCode {}
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(value = {
+            SUCCESS,
+            ERROR_INVALID_LENGTH,
+            ERROR_UNSUPPORTED,
+            ERROR_INSUFFICIENT_RESOURCES,
+            ERROR_HARDWARE_UNSUPPORTED
+    })
+    public @interface KeepaliveEvent {}
+
+    /**
+     * The minimum interval in seconds between keepalive packet transmissions.
+     *
+     * @hide
+     **/
+    public static final int MIN_INTERVAL_SEC = 10;
+
+    /**
+     * The maximum interval in seconds between keepalive packet transmissions.
+     *
+     * @hide
+     **/
+    public static final int MAX_INTERVAL_SEC = 3600;
+
+    /**
+     * An exception that embarks an error code.
+     * @hide
+     */
+    public static class ErrorCodeException extends Exception {
+        public final int error;
+        public ErrorCodeException(final int error, final Throwable e) {
+            super(e);
+            this.error = error;
+        }
+        public ErrorCodeException(final int error) {
+            this.error = error;
+        }
+    }
+
+    /**
+     * This socket is invalid.
+     * See the error code for details, and the optional cause.
+     * @hide
+     */
+    public static class InvalidSocketException extends ErrorCodeException {
+        public InvalidSocketException(final int error, final Throwable e) {
+            super(error, e);
+        }
+        public InvalidSocketException(final int error) {
+            super(error);
+        }
+    }
+
+    @NonNull final IConnectivityManager mService;
+    @NonNull final Network mNetwork;
+    @NonNull final ParcelFileDescriptor mPfd;
+    @NonNull final Executor mExecutor;
+    @NonNull final ISocketKeepaliveCallback mCallback;
+    // TODO: remove slot since mCallback could be used to identify which keepalive to stop.
+    @Nullable Integer mSlot;
+
+    SocketKeepalive(@NonNull IConnectivityManager service, @NonNull Network network,
+            @NonNull ParcelFileDescriptor pfd,
+            @NonNull Executor executor, @NonNull Callback callback) {
+        mService = service;
+        mNetwork = network;
+        mPfd = pfd;
+        mExecutor = executor;
+        mCallback = new ISocketKeepaliveCallback.Stub() {
+            @Override
+            public void onStarted(int slot) {
+                final long token = Binder.clearCallingIdentity();
+                try {
+                    mExecutor.execute(() -> {
+                        mSlot = slot;
+                        callback.onStarted();
+                    });
+                } finally {
+                    Binder.restoreCallingIdentity(token);
+                }
+            }
+
+            @Override
+            public void onStopped() {
+                final long token = Binder.clearCallingIdentity();
+                try {
+                    executor.execute(() -> {
+                        mSlot = null;
+                        callback.onStopped();
+                    });
+                } finally {
+                    Binder.restoreCallingIdentity(token);
+                }
+            }
+
+            @Override
+            public void onError(int error) {
+                final long token = Binder.clearCallingIdentity();
+                try {
+                    executor.execute(() -> {
+                        mSlot = null;
+                        callback.onError(error);
+                    });
+                } finally {
+                    Binder.restoreCallingIdentity(token);
+                }
+            }
+
+            @Override
+            public void onDataReceived() {
+                final long token = Binder.clearCallingIdentity();
+                try {
+                    executor.execute(() -> {
+                        mSlot = null;
+                        callback.onDataReceived();
+                    });
+                } finally {
+                    Binder.restoreCallingIdentity(token);
+                }
+            }
+        };
+    }
+
+    /**
+     * Request that keepalive be started with the given {@code intervalSec}. See
+     * {@link SocketKeepalive}. If the remote binder dies, or the binder call throws an exception
+     * when invoking start or stop of the {@link SocketKeepalive}, a {@link RemoteException} will be
+     * thrown into the {@code executor}. This is typically not important to catch because the remote
+     * party is the system, so if it is not in shape to communicate through binder the system is
+     * probably going down anyway. If the caller cares regardless, it can use a custom
+     * {@link Executor} to catch the {@link RemoteException}.
+     *
+     * @param intervalSec The target interval in seconds between keepalive packet transmissions.
+     *                    The interval should be between 10 seconds and 3600 seconds, otherwise
+     *                    {@link #ERROR_INVALID_INTERVAL} will be returned.
+     */
+    public final void start(@IntRange(from = MIN_INTERVAL_SEC, to = MAX_INTERVAL_SEC)
+            int intervalSec) {
+        startImpl(intervalSec);
+    }
+
+    abstract void startImpl(int intervalSec);
+
+    /**
+     * Requests that keepalive be stopped. The application must wait for {@link Callback#onStopped}
+     * before using the object. See {@link SocketKeepalive}.
+     */
+    public final void stop() {
+        stopImpl();
+    }
+
+    abstract void stopImpl();
+
+    /**
+     * Deactivate this {@link SocketKeepalive} and free allocated resources. The instance won't be
+     * usable again if {@code close()} is called.
+     */
+    @Override
+    public final void close() {
+        stop();
+        try {
+            mPfd.close();
+        } catch (IOException e) {
+            // Nothing much can be done.
+        }
+    }
+
+    /**
+     * The callback which app can use to learn the status changes of {@link SocketKeepalive}. See
+     * {@link SocketKeepalive}.
+     */
+    public static class Callback {
+        /** The requested keepalive was successfully started. */
+        public void onStarted() {}
+        /** The keepalive was successfully stopped. */
+        public void onStopped() {}
+        /** An error occurred. */
+        public void onError(@ErrorCode int error) {}
+        /** The keepalive on a TCP socket was stopped because the socket received data. This is
+         * never called for UDP sockets. */
+        public void onDataReceived() {}
+    }
+}