| /* |
| * Copyright (C) 2009 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.bluetooth; |
| |
| import android.bluetooth.IBluetoothCallback; |
| import android.os.ParcelUuid; |
| import android.os.RemoteException; |
| import android.util.Log; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.util.concurrent.locks.ReentrantReadWriteLock; |
| |
| /** |
| * A connected or connecting Bluetooth socket. |
| * |
| * <p>The interface for Bluetooth Sockets is similar to that of TCP sockets: |
| * {@link java.net.Socket} and {@link java.net.ServerSocket}. On the server |
| * side, use a {@link BluetoothServerSocket} to create a listening server |
| * socket. When a connection is accepted by the {@link BluetoothServerSocket}, |
| * it will return a new {@link BluetoothSocket} to manage the connection. |
| * On the client side, use a single {@link BluetoothSocket} to both initiate |
| * an outgoing connection and to manage the connection. |
| * |
| * <p>The most common type of Bluetooth socket is RFCOMM, which is the type |
| * supported by the Android APIs. RFCOMM is a connection-oriented, streaming |
| * transport over Bluetooth. It is also known as the Serial Port Profile (SPP). |
| * |
| * <p>To create a {@link BluetoothSocket} for connecting to a known device, use |
| * {@link BluetoothDevice#createRfcommSocketToServiceRecord |
| * BluetoothDevice.createRfcommSocketToServiceRecord()}. |
| * Then call {@link #connect()} to attempt a connection to the remote device. |
| * This call will block until a connection is established or the connection |
| * fails. |
| * |
| * <p>To create a {@link BluetoothSocket} as a server (or "host"), see the |
| * {@link BluetoothServerSocket} documentation. |
| * |
| * <p>Once the socket is connected, whether initiated as a client or accepted |
| * as a server, open the IO streams by calling {@link #getInputStream} and |
| * {@link #getOutputStream} in order to retrieve {@link java.io.InputStream} |
| * and {@link java.io.OutputStream} objects, respectively, which are |
| * automatically connected to the socket. |
| * |
| * <p>{@link BluetoothSocket} is thread |
| * safe. In particular, {@link #close} will always immediately abort ongoing |
| * operations and close the socket. |
| * |
| * <p class="note"><strong>Note:</strong> |
| * Requires the {@link android.Manifest.permission#BLUETOOTH} permission. |
| * |
| * {@see BluetoothServerSocket} |
| * {@see java.io.InputStream} |
| * {@see java.io.OutputStream} |
| */ |
| public final class BluetoothSocket implements Closeable { |
| private static final String TAG = "BluetoothSocket"; |
| |
| /** @hide */ |
| public static final int MAX_RFCOMM_CHANNEL = 30; |
| |
| /** Keep TYPE_ fields in sync with BluetoothSocket.cpp */ |
| /*package*/ static final int TYPE_RFCOMM = 1; |
| /*package*/ static final int TYPE_SCO = 2; |
| /*package*/ static final int TYPE_L2CAP = 3; |
| |
| /*package*/ static final int EBADFD = 77; |
| /*package*/ static final int EADDRINUSE = 98; |
| |
| private final int mType; /* one of TYPE_RFCOMM etc */ |
| private final BluetoothDevice mDevice; /* remote device */ |
| private final String mAddress; /* remote address */ |
| private final boolean mAuth; |
| private final boolean mEncrypt; |
| private final BluetoothInputStream mInputStream; |
| private final BluetoothOutputStream mOutputStream; |
| private final SdpHelper mSdp; |
| |
| private int mPort; /* RFCOMM channel or L2CAP psm */ |
| |
| private enum SocketState { |
| INIT, |
| CONNECTED, |
| CLOSED |
| } |
| |
| /** prevents all native calls after destroyNative() */ |
| private SocketState mSocketState; |
| |
| /** protects mSocketState */ |
| private final ReentrantReadWriteLock mLock; |
| |
| /** used by native code only */ |
| private int mSocketData; |
| |
| /** |
| * Construct a BluetoothSocket. |
| * @param type type of socket |
| * @param fd fd to use for connected socket, or -1 for a new socket |
| * @param auth require the remote device to be authenticated |
| * @param encrypt require the connection to be encrypted |
| * @param device remote device that this socket can connect to |
| * @param port remote port |
| * @param uuid SDP uuid |
| * @throws IOException On error, for example Bluetooth not available, or |
| * insufficient privileges |
| */ |
| /*package*/ BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, |
| BluetoothDevice device, int port, ParcelUuid uuid) throws IOException { |
| if (type == BluetoothSocket.TYPE_RFCOMM && uuid == null && fd == -1) { |
| if (port < 1 || port > MAX_RFCOMM_CHANNEL) { |
| throw new IOException("Invalid RFCOMM channel: " + port); |
| } |
| } |
| if (uuid == null) { |
| mPort = port; |
| mSdp = null; |
| } else { |
| mSdp = new SdpHelper(device, uuid); |
| mPort = -1; |
| } |
| mType = type; |
| mAuth = auth; |
| mEncrypt = encrypt; |
| mDevice = device; |
| if (device == null) { |
| mAddress = null; |
| } else { |
| mAddress = device.getAddress(); |
| } |
| if (fd == -1) { |
| initSocketNative(); |
| } else { |
| initSocketFromFdNative(fd); |
| } |
| mInputStream = new BluetoothInputStream(this); |
| mOutputStream = new BluetoothOutputStream(this); |
| mSocketState = SocketState.INIT; |
| mLock = new ReentrantReadWriteLock(); |
| } |
| |
| /** |
| * Construct a BluetoothSocket from address. Used by native code. |
| * @param type type of socket |
| * @param fd fd to use for connected socket, or -1 for a new socket |
| * @param auth require the remote device to be authenticated |
| * @param encrypt require the connection to be encrypted |
| * @param address remote device that this socket can connect to |
| * @param port remote port |
| * @throws IOException On error, for example Bluetooth not available, or |
| * insufficient privileges |
| */ |
| private BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, String address, |
| int port) throws IOException { |
| this(type, fd, auth, encrypt, new BluetoothDevice(address), port, null); |
| } |
| |
| /** @hide */ |
| @Override |
| protected void finalize() throws Throwable { |
| try { |
| close(); |
| } finally { |
| super.finalize(); |
| } |
| } |
| |
| /** |
| * Attempt to connect to a remote device. |
| * <p>This method will block until a connection is made or the connection |
| * fails. If this method returns without an exception then this socket |
| * is now connected. |
| * <p>Creating new connections to |
| * remote Bluetooth devices should not be attempted while device discovery |
| * is in progress. Device discovery is a heavyweight procedure on the |
| * Bluetooth adapter and will significantly slow a device connection. |
| * Use {@link BluetoothAdapter#cancelDiscovery()} to cancel an ongoing |
| * discovery. Discovery is not managed by the Activity, |
| * but is run as a system service, so an application should always call |
| * {@link BluetoothAdapter#cancelDiscovery()} even if it |
| * did not directly request a discovery, just to be sure. |
| * <p>{@link #close} can be used to abort this call from another thread. |
| * @throws IOException on error, for example connection failure |
| */ |
| public void connect() throws IOException { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed"); |
| |
| if (mSdp != null) { |
| mPort = mSdp.doSdp(); // blocks |
| } |
| |
| connectNative(); // blocks |
| mSocketState = SocketState.CONNECTED; |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| /** |
| * Immediately close this socket, and release all associated resources. |
| * <p>Causes blocked calls on this socket in other threads to immediately |
| * throw an IOException. |
| */ |
| public void close() throws IOException { |
| // abort blocking operations on the socket |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) return; |
| if (mSdp != null) { |
| mSdp.cancel(); |
| } |
| abortNative(); |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| |
| // all native calls are guaranteed to immediately return after |
| // abortNative(), so this lock should immediately acquire |
| mLock.writeLock().lock(); |
| try { |
| mSocketState = SocketState.CLOSED; |
| destroyNative(); |
| } finally { |
| mLock.writeLock().unlock(); |
| } |
| } |
| |
| /** |
| * Get the remote device this socket is connecting, or connected, to. |
| * @return remote device |
| */ |
| public BluetoothDevice getRemoteDevice() { |
| return mDevice; |
| } |
| |
| /** |
| * Get the input stream associated with this socket. |
| * <p>The input stream will be returned even if the socket is not yet |
| * connected, but operations on that stream will throw IOException until |
| * the associated socket is connected. |
| * @return InputStream |
| */ |
| public InputStream getInputStream() throws IOException { |
| return mInputStream; |
| } |
| |
| /** |
| * Get the output stream associated with this socket. |
| * <p>The output stream will be returned even if the socket is not yet |
| * connected, but operations on that stream will throw IOException until |
| * the associated socket is connected. |
| * @return OutputStream |
| */ |
| public OutputStream getOutputStream() throws IOException { |
| return mOutputStream; |
| } |
| |
| /** |
| * Get the connection status of this socket, ie, whether there is an active connection with |
| * remote device. |
| * @return true if connected |
| * false if not connected |
| */ |
| public boolean isConnected() { |
| return (mSocketState == SocketState.CONNECTED); |
| } |
| |
| /** |
| * Currently returns unix errno instead of throwing IOException, |
| * so that BluetoothAdapter can check the error code for EADDRINUSE |
| */ |
| /*package*/ int bindListen() { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) return EBADFD; |
| return bindListenNative(); |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| /*package*/ BluetoothSocket accept(int timeout) throws IOException { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed"); |
| |
| BluetoothSocket acceptedSocket = acceptNative(timeout); |
| mSocketState = SocketState.CONNECTED; |
| return acceptedSocket; |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| /*package*/ int available() throws IOException { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed"); |
| return availableNative(); |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| /*package*/ int read(byte[] b, int offset, int length) throws IOException { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed"); |
| return readNative(b, offset, length); |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| /*package*/ int write(byte[] b, int offset, int length) throws IOException { |
| mLock.readLock().lock(); |
| try { |
| if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed"); |
| return writeNative(b, offset, length); |
| } finally { |
| mLock.readLock().unlock(); |
| } |
| } |
| |
| private native void initSocketNative() throws IOException; |
| private native void initSocketFromFdNative(int fd) throws IOException; |
| private native void connectNative() throws IOException; |
| private native int bindListenNative(); |
| private native BluetoothSocket acceptNative(int timeout) throws IOException; |
| private native int availableNative() throws IOException; |
| private native int readNative(byte[] b, int offset, int length) throws IOException; |
| private native int writeNative(byte[] b, int offset, int length) throws IOException; |
| private native void abortNative() throws IOException; |
| private native void destroyNative() throws IOException; |
| /** |
| * Throws an IOException for given posix errno. Done natively so we can |
| * use strerr to convert to string error. |
| */ |
| /*package*/ native void throwErrnoNative(int errno) throws IOException; |
| |
| /** |
| * Helper to perform blocking SDP lookup. |
| */ |
| private static class SdpHelper extends IBluetoothCallback.Stub { |
| private final IBluetooth service; |
| private final ParcelUuid uuid; |
| private final BluetoothDevice device; |
| private int channel; |
| private boolean canceled; |
| public SdpHelper(BluetoothDevice device, ParcelUuid uuid) { |
| service = BluetoothDevice.getService(); |
| this.device = device; |
| this.uuid = uuid; |
| canceled = false; |
| } |
| /** |
| * Returns the RFCOMM channel for the UUID, or throws IOException |
| * on failure. |
| */ |
| public synchronized int doSdp() throws IOException { |
| if (canceled) throw new IOException("Service discovery canceled"); |
| channel = -1; |
| |
| boolean inProgress = false; |
| try { |
| inProgress = service.fetchRemoteUuids(device.getAddress(), uuid, this); |
| } catch (RemoteException e) {Log.e(TAG, "", e);} |
| |
| if (!inProgress) throw new IOException("Unable to start Service Discovery"); |
| |
| try { |
| /* 12 second timeout as a precaution - onRfcommChannelFound |
| * should always occur before the timeout */ |
| wait(12000); // block |
| |
| } catch (InterruptedException e) {} |
| |
| if (canceled) throw new IOException("Service discovery canceled"); |
| if (channel < 1) throw new IOException("Service discovery failed"); |
| |
| return channel; |
| } |
| /** Object cannot be re-used after calling cancel() */ |
| public synchronized void cancel() { |
| if (!canceled) { |
| canceled = true; |
| channel = -1; |
| notifyAll(); // unblock |
| } |
| } |
| public synchronized void onRfcommChannelFound(int channel) { |
| if (!canceled) { |
| this.channel = channel; |
| notifyAll(); // unblock |
| } |
| } |
| } |
| } |