diff options
Diffstat (limited to 'core/java/android/bluetooth/BluetoothSocket.java')
| -rw-r--r-- | core/java/android/bluetooth/BluetoothSocket.java | 355 |
1 files changed, 283 insertions, 72 deletions
diff --git a/core/java/android/bluetooth/BluetoothSocket.java b/core/java/android/bluetooth/BluetoothSocket.java index fd8885e..dbcc758 100644 --- a/core/java/android/bluetooth/BluetoothSocket.java +++ b/core/java/android/bluetooth/BluetoothSocket.java @@ -16,83 +16,128 @@ 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; /** - * Represents a connected or connecting Bluetooth Socket. + * 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 intiate + * 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. * - * Currently only supports RFCOMM sockets. + * <p>{@link BluetoothSocket} is thread + * safe. In particular, {@link #close} will always immediately abort ongoing + * operations and close the socket. * - * RFCOMM is a connection orientated, streaming transport over Bluetooth. It is - * also known as the Serial Port Profile (SPP). + * <p class="note"><strong>Note:</strong> + * Requires the {@link android.Manifest.permission#BLUETOOTH} permission. * - * TODO: Consider implementing SCO and L2CAP sockets. - * TODO: Clean up javadoc grammer and formatting. - * TODO: Remove @hide - * @hide + * {@see BluetoothServerSocket} + * {@see java.io.InputStream} + * {@see java.io.OutputStream} */ public final class BluetoothSocket implements Closeable { - private final int mPort; + 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 mSocketData; /* used by native code only */ + private int mPort; /* RFCOMM channel or L2CAP psm */ - /** - * Construct a secure RFCOMM socket ready to start an outgoing connection. - * Call #connect on the returned #BluetoothSocket to begin the connection. - * The remote device will be authenticated and communication on this socket - * will be encrypted. - * @param address remote Bluetooth address that this socket can connect to - * @param port remote port - * @return an RFCOMM BluetoothSocket - * @throws IOException on error, for example Bluetooth not available, or - * insufficient permissions. - */ - public static BluetoothSocket createRfcommSocket(String address, int port) - throws IOException { - return new BluetoothSocket(-1, true, true, address, port); - } + /** prevents all native calls after destroyNative() */ + private boolean mClosed; - /** - * Construct an insecure RFCOMM socket ready to start an outgoing - * connection. - * Call #connect on the returned #BluetoothSocket to begin the connection. - * The remote device will not be authenticated and communication on this - * socket will not be encrypted. - * @param address remote Bluetooth address that this socket can connect to - * @param port remote port - * @return An RFCOMM BluetoothSocket - * @throws IOException On error, for example Bluetooth not available, or - * insufficient permissions. - */ - public static BluetoothSocket createInsecureRfcommSocket(String address, int port) - throws IOException { - return new BluetoothSocket(-1, false, false, address, port); - } + /** protects mClosed */ + private final ReentrantReadWriteLock mLock; + + /** used by native code only */ + private int mSocketData; /** - * Construct a Bluetooth. + * 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 address remote Bluetooth address that this socket can connect to + * @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 priveleges */ - /*package*/ BluetoothSocket(int fd, boolean auth, boolean encrypt, String address, int port) - throws IOException { + /*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; - mAddress = address; - mPort = port; + mDevice = device; + if (device == null) { + mAddress = null; + } else { + mAddress = device.getAddress(); + } if (fd == -1) { initSocketNative(); } else { @@ -100,8 +145,27 @@ public final class BluetoothSocket implements Closeable { } mInputStream = new BluetoothInputStream(this); mOutputStream = new BluetoothOutputStream(this); + mClosed = false; + 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 priveleges + */ + 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 { @@ -113,37 +177,67 @@ public final class BluetoothSocket implements Closeable { /** * Attempt to connect to a remote device. - * This method will block until a connection is made or the connection + * <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. #close can be used to abort this call from another - * thread. - * @throws IOException On error, for example connection failure + * is now connected. + * <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 { - connectNative(mAddress, mPort, -1); + mLock.readLock().lock(); + try { + if (mClosed) throw new IOException("socket closed"); + + if (mSdp != null) { + mPort = mSdp.doSdp(); // blocks + } + + connectNative(); // blocks + } finally { + mLock.readLock().unlock(); + } } /** - * Closes this socket. - * This will cause other blocking calls on this socket to immediately + * 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 { - closeNative(); + // abort blocking operations on the socket + mLock.readLock().lock(); + try { + if (mClosed) 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 immediatley acquire + mLock.writeLock().lock(); + try { + mClosed = true; + destroyNative(); + } finally { + mLock.writeLock().unlock(); + } } /** - * Return the address we are connecting, or connected, to. - * @return Bluetooth address, or null if this socket has not yet attempted - * or established a connection. + * Get the remote device this socket is connecting, or connected, to. + * @return remote device */ - public String getAddress() { - return mAddress; + public BluetoothDevice getRemoteDevice() { + return mDevice; } /** * Get the input stream associated with this socket. - * The input stream will be returned even if the socket is not yet + * <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 @@ -154,7 +248,7 @@ public final class BluetoothSocket implements Closeable { /** * Get the output stream associated with this socket. - * The output stream will be returned even if the socket is not yet + * <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 @@ -163,14 +257,131 @@ public final class BluetoothSocket implements Closeable { return mOutputStream; } - private native void initSocketNative(); - private native void initSocketFromFdNative(int fd); - private native void connectNative(String address, int port, int timeout); - /*package*/ native void bindListenNative(int port) throws IOException; - /*package*/ native BluetoothSocket acceptNative(int timeout) throws IOException; - /*package*/ native int availableNative(); - /*package*/ native int readNative(); - /*package*/ native void writeNative(int data); - /*package*/ native void closeNative(); - private native void destroyNative(); + /** + * 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 (mClosed) return EBADFD; + return bindListenNative(); + } finally { + mLock.readLock().unlock(); + } + } + + /*package*/ BluetoothSocket accept(int timeout) throws IOException { + mLock.readLock().lock(); + try { + if (mClosed) throw new IOException("socket closed"); + return acceptNative(timeout); + } finally { + mLock.readLock().unlock(); + } + } + + /*package*/ int available() throws IOException { + mLock.readLock().lock(); + try { + if (mClosed) 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 (mClosed) 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 (mClosed) 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 + } + } + } } |