services/java/com/android/server/ViewServer.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2007 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.server;

 import android.util.Slog;

 import java.net.ServerSocket;
 import java.net.Socket;
 import java.net.InetAddress;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.io.IOException;
 import java.io.BufferedReader;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.BufferedWriter;
 import java.io.OutputStreamWriter;

 /**
  * The ViewServer is local socket server that can be used to communicate with the
  * views of the opened windows. Communication with the views is ensured by the
  * {@link com.android.server.WindowManagerService} and is a cross-process operation.
  *
  * {@hide}
  */
 class ViewServer implements Runnable {
     /**
      * The default port used to start view servers.
      */
     public static final int VIEW_SERVER_DEFAULT_PORT = 4939;

     private static final int VIEW_SERVER_MAX_CONNECTIONS = 10;

     // Debug facility
     private static final String LOG_TAG = "ViewServer";

     private static final String VALUE_PROTOCOL_VERSION = "3";
     private static final String VALUE_SERVER_VERSION = "4";

     // Protocol commands
     // Returns the protocol version
     private static final String COMMAND_PROTOCOL_VERSION = "PROTOCOL";
     // Returns the server version
     private static final String COMMAND_SERVER_VERSION = "SERVER";
     // Lists all of the available windows in the system
     private static final String COMMAND_WINDOW_MANAGER_LIST = "LIST";
     // Keeps a connection open and notifies when the list of windows changes
     private static final String COMMAND_WINDOW_MANAGER_AUTOLIST = "AUTOLIST";

     private ServerSocket mServer;
     private Thread mThread;

     private final WindowManagerService mWindowManager;
     private final int mPort;

     private ExecutorService mThreadPool;

     /**
      * Creates a new ViewServer associated with the specified window manager.
      * The server uses the default port {@link #VIEW_SERVER_DEFAULT_PORT}. The server
      * is not started by default.
      *
      * @param windowManager The window manager used to communicate with the views.
      *
      * @see #start()
      */
     ViewServer(WindowManagerService windowManager) {
         this(windowManager, VIEW_SERVER_DEFAULT_PORT);
     }

     /**
      * Creates a new ViewServer associated with the specified window manager on the
      * specified local port. The server is not started by default.
      *
      * @param windowManager The window manager used to communicate with the views.
      * @param port The port for the server to listen to.
      *
      * @see #start()
      */
     ViewServer(WindowManagerService windowManager, int port) {
         mWindowManager = windowManager;
         mPort = port;
     }

     /**
      * Starts the server.
      *
      * @return True if the server was successfully created, or false if it already exists.
      * @throws IOException If the server cannot be created.
      *
      * @see #stop()
      * @see #isRunning()
      * @see WindowManagerService#startViewServer(int)
      */
     boolean start() throws IOException {
         if (mThread != null) {
             return false;
         }

         mServer = new ServerSocket(mPort, VIEW_SERVER_MAX_CONNECTIONS, InetAddress.getLocalHost());
         mThread = new Thread(this, "Remote View Server [port=" + mPort + "]");
         mThreadPool = Executors.newFixedThreadPool(VIEW_SERVER_MAX_CONNECTIONS);
         mThread.start();

         return true;
     }

     /**
      * Stops the server.
      *
      * @return True if the server was stopped, false if an error occured or if the
      *         server wasn't started.
      *
      * @see #start()
      * @see #isRunning()
      * @see WindowManagerService#stopViewServer()
      */
     boolean stop() {
         if (mThread != null) {

             mThread.interrupt();
             if (mThreadPool != null) {
                 try {
                     mThreadPool.shutdownNow();
                 } catch (SecurityException e) {
                     Slog.w(LOG_TAG, "Could not stop all view server threads");
                 }
             }
             mThreadPool = null;
             mThread = null;
             try {
                 mServer.close();
                 mServer = null;
                 return true;
             } catch (IOException e) {
                 Slog.w(LOG_TAG, "Could not close the view server");
             }
         }
         return false;
     }

     /**
      * Indicates whether the server is currently running.
      *
      * @return True if the server is running, false otherwise.
      *
      * @see #start()
      * @see #stop()
      * @see WindowManagerService#isViewServerRunning()
      */
     boolean isRunning() {
         return mThread != null && mThread.isAlive();
     }

     /**
      * Main server loop.
      */
     public void run() {
         while (Thread.currentThread() == mThread) {
             // Any uncaught exception will crash the system process
             try {
                 Socket client = mServer.accept();
                 if(mThreadPool != null) {
                     mThreadPool.submit(new ViewServerWorker(client));
                 } else {
                     try {
                         client.close();
                     } catch (IOException e) {
                         e.printStackTrace();
                     }
                 }
             } catch (Exception e) {
                 Slog.w(LOG_TAG, "Connection error: ", e);
             }
         }
     }

     private static boolean writeValue(Socket client, String value) {
         boolean result;
         BufferedWriter out = null;
         try {
             OutputStream clientStream = client.getOutputStream();
             out = new BufferedWriter(new OutputStreamWriter(clientStream), 8 * 1024);
             out.write(value);
             out.write("\n");
             out.flush();
             result = true;
         } catch (Exception e) {
             result = false;
         } finally {
             if (out != null) {
                 try {
                     out.close();
                 } catch (IOException e) {
                     result = false;
                 }
             }
         }
         return result;
     }

     class ViewServerWorker implements Runnable, WindowManagerService.WindowChangeListener {
         private Socket mClient;
         private boolean mNeedWindowListUpdate;
         private boolean mNeedFocusedWindowUpdate;
         public ViewServerWorker(Socket client) {
             mClient = client;
             mNeedWindowListUpdate = false;
             mNeedFocusedWindowUpdate = false;
         }

         public void run() {

             BufferedReader in = null;
             try {
                 in = new BufferedReader(new InputStreamReader(mClient.getInputStream()), 1024);

                 final String request = in.readLine();

                 String command;
                 String parameters;

                 int index = request.indexOf(' ');
                 if (index == -1) {
                     command = request;
                     parameters = "";
                 } else {
                     command = request.substring(0, index);
                     parameters = request.substring(index + 1);
                 }

                 boolean result;
                 if (COMMAND_PROTOCOL_VERSION.equalsIgnoreCase(command)) {
                     result = writeValue(mClient, VALUE_PROTOCOL_VERSION);
                 } else if (COMMAND_SERVER_VERSION.equalsIgnoreCase(command)) {
                     result = writeValue(mClient, VALUE_SERVER_VERSION);
                 } else if (COMMAND_WINDOW_MANAGER_LIST.equalsIgnoreCase(command)) {
                     result = mWindowManager.viewServerListWindows(mClient);
                 } else if(COMMAND_WINDOW_MANAGER_AUTOLIST.equalsIgnoreCase(command)) {
                     result = windowManagerAutolistLoop();
                 } else {
                     result = mWindowManager.viewServerWindowCommand(mClient,
                             command, parameters);
                 }

                 if (!result) {
                     Slog.w(LOG_TAG, "An error occured with the command: " + command);
                 }
             } catch(IOException e) {
                 Slog.w(LOG_TAG, "Connection error: ", e);
             } finally {
                 if (in != null) {
                     try {
                         in.close();

                     } catch (IOException e) {
                         e.printStackTrace();
                     }
                 }
                 if (mClient != null) {
                     try {
                         mClient.close();
                     } catch (IOException e) {
                         e.printStackTrace();
                     }
                 }
             }
         }

         public void windowsChanged() {
             synchronized(this) {
                 mNeedWindowListUpdate = true;
                 notifyAll();
             }
         }

         public void focusChanged() {
             synchronized(this) {
                 mNeedFocusedWindowUpdate = true;
                 notifyAll();
             }
         }

         private boolean windowManagerAutolistLoop() {
             mWindowManager.addWindowChangeListener(this);
             BufferedWriter out = null;
             try {
                 out = new BufferedWriter(new OutputStreamWriter(mClient.getOutputStream()));
                 while (!Thread.interrupted()) {
                     boolean needWindowListUpdate = false;
                     boolean needFocusedWindowUpdate = false;
                     synchronized (this) {
                         while (!mNeedWindowListUpdate && !mNeedFocusedWindowUpdate) {
                             wait();
                         }
                         if (mNeedWindowListUpdate) {
                             mNeedWindowListUpdate = false;
                             needWindowListUpdate = true;
                         }
                         if (mNeedFocusedWindowUpdate) {
                             mNeedFocusedWindowUpdate = false;
                             needFocusedWindowUpdate = true;
                         }
                     }
                     if(needWindowListUpdate) {
                         out.write("LIST UPDATE\n");
                         out.flush();
                     }
                     if(needFocusedWindowUpdate) {
                         out.write("FOCUS UPDATE\n");
                         out.flush();
                     }
                 }
             } catch (Exception e) {
                 Slog.w(LOG_TAG, "Connection error: ", e);
             } finally {
                 if (out != null) {
                     try {
                         out.close();
                     } catch (IOException e) {
                     }
                 }
                 mWindowManager.removeWindowChangeListener(this);
             }
             return true;
         }
     }
 }
	/*
	* Copyright (C) 2007 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.server;

	import android.util.Slog;

	import java.net.ServerSocket;
	import java.net.Socket;
	import java.net.InetAddress;
	import java.util.concurrent.ExecutorService;
	import java.util.concurrent.Executors;
	import java.io.IOException;
	import java.io.BufferedReader;
	import java.io.InputStreamReader;
	import java.io.OutputStream;
	import java.io.BufferedWriter;
	import java.io.OutputStreamWriter;

	/**
	* The ViewServer is local socket server that can be used to communicate with the
	* views of the opened windows. Communication with the views is ensured by the
	* {@link com.android.server.WindowManagerService} and is a cross-process operation.
	*
	* {@hide}
	*/
	class ViewServer implements Runnable {
	/**
	* The default port used to start view servers.
	*/
	public static final int VIEW_SERVER_DEFAULT_PORT = 4939;

	private static final int VIEW_SERVER_MAX_CONNECTIONS = 10;

	// Debug facility
	private static final String LOG_TAG = "ViewServer";

	private static final String VALUE_PROTOCOL_VERSION = "3";
	private static final String VALUE_SERVER_VERSION = "4";

	// Protocol commands
	// Returns the protocol version
	private static final String COMMAND_PROTOCOL_VERSION = "PROTOCOL";
	// Returns the server version
	private static final String COMMAND_SERVER_VERSION = "SERVER";
	// Lists all of the available windows in the system
	private static final String COMMAND_WINDOW_MANAGER_LIST = "LIST";
	// Keeps a connection open and notifies when the list of windows changes
	private static final String COMMAND_WINDOW_MANAGER_AUTOLIST = "AUTOLIST";

	private ServerSocket mServer;
	private Thread mThread;

	private final WindowManagerService mWindowManager;
	private final int mPort;

	private ExecutorService mThreadPool;

	/**
	* Creates a new ViewServer associated with the specified window manager.
	* The server uses the default port {@link #VIEW_SERVER_DEFAULT_PORT}. The server
	* is not started by default.
	*
	* @param windowManager The window manager used to communicate with the views.
	*
	* @see #start()
	*/
	ViewServer(WindowManagerService windowManager) {
	this(windowManager, VIEW_SERVER_DEFAULT_PORT);
	}

	/**
	* Creates a new ViewServer associated with the specified window manager on the
	* specified local port. The server is not started by default.
	*
	* @param windowManager The window manager used to communicate with the views.
	* @param port The port for the server to listen to.
	*
	* @see #start()
	*/
	ViewServer(WindowManagerService windowManager, int port) {
	mWindowManager = windowManager;
	mPort = port;
	}

	/**
	* Starts the server.
	*
	* @return True if the server was successfully created, or false if it already exists.
	* @throws IOException If the server cannot be created.
	*
	* @see #stop()
	* @see #isRunning()
	* @see WindowManagerService#startViewServer(int)
	*/
	boolean start() throws IOException {
	if (mThread != null) {
	return false;
	}

	mServer = new ServerSocket(mPort, VIEW_SERVER_MAX_CONNECTIONS, InetAddress.getLocalHost());
	mThread = new Thread(this, "Remote View Server [port=" + mPort + "]");
	mThreadPool = Executors.newFixedThreadPool(VIEW_SERVER_MAX_CONNECTIONS);
	mThread.start();

	return true;
	}

	/**
	* Stops the server.
	*
	* @return True if the server was stopped, false if an error occured or if the
	* server wasn't started.
	*
	* @see #start()
	* @see #isRunning()
	* @see WindowManagerService#stopViewServer()
	*/
	boolean stop() {
	if (mThread != null) {

	mThread.interrupt();
	if (mThreadPool != null) {
	try {
	mThreadPool.shutdownNow();
	} catch (SecurityException e) {
	Slog.w(LOG_TAG, "Could not stop all view server threads");
	}
	}
	mThreadPool = null;
	mThread = null;
	try {
	mServer.close();
	mServer = null;
	return true;
	} catch (IOException e) {
	Slog.w(LOG_TAG, "Could not close the view server");
	}
	}
	return false;
	}

	/**
	* Indicates whether the server is currently running.
	*
	* @return True if the server is running, false otherwise.
	*
	* @see #start()
	* @see #stop()
	* @see WindowManagerService#isViewServerRunning()
	*/
	boolean isRunning() {
	return mThread != null && mThread.isAlive();
	}

	/**
	* Main server loop.
	*/
	public void run() {
	while (Thread.currentThread() == mThread) {
	// Any uncaught exception will crash the system process
	try {
	Socket client = mServer.accept();
	if(mThreadPool != null) {
	mThreadPool.submit(new ViewServerWorker(client));
	} else {
	try {
	client.close();
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	} catch (Exception e) {
	Slog.w(LOG_TAG, "Connection error: ", e);
	}
	}
	}

	private static boolean writeValue(Socket client, String value) {
	boolean result;
	BufferedWriter out = null;
	try {
	OutputStream clientStream = client.getOutputStream();
	out = new BufferedWriter(new OutputStreamWriter(clientStream), 8 * 1024);
	out.write(value);
	out.write("\n");
	out.flush();
	result = true;
	} catch (Exception e) {
	result = false;
	} finally {
	if (out != null) {
	try {
	out.close();
	} catch (IOException e) {
	result = false;
	}
	}
	}
	return result;
	}

	class ViewServerWorker implements Runnable, WindowManagerService.WindowChangeListener {
	private Socket mClient;
	private boolean mNeedWindowListUpdate;
	private boolean mNeedFocusedWindowUpdate;
	public ViewServerWorker(Socket client) {
	mClient = client;
	mNeedWindowListUpdate = false;
	mNeedFocusedWindowUpdate = false;
	}

	public void run() {

	BufferedReader in = null;
	try {
	in = new BufferedReader(new InputStreamReader(mClient.getInputStream()), 1024);

	final String request = in.readLine();

	String command;
	String parameters;

	int index = request.indexOf(' ');
	if (index == -1) {
	command = request;
	parameters = "";
	} else {
	command = request.substring(0, index);
	parameters = request.substring(index + 1);
	}

	boolean result;
	if (COMMAND_PROTOCOL_VERSION.equalsIgnoreCase(command)) {
	result = writeValue(mClient, VALUE_PROTOCOL_VERSION);
	} else if (COMMAND_SERVER_VERSION.equalsIgnoreCase(command)) {
	result = writeValue(mClient, VALUE_SERVER_VERSION);
	} else if (COMMAND_WINDOW_MANAGER_LIST.equalsIgnoreCase(command)) {
	result = mWindowManager.viewServerListWindows(mClient);
	} else if(COMMAND_WINDOW_MANAGER_AUTOLIST.equalsIgnoreCase(command)) {
	result = windowManagerAutolistLoop();
	} else {
	result = mWindowManager.viewServerWindowCommand(mClient,
	command, parameters);
	}

	if (!result) {
	Slog.w(LOG_TAG, "An error occured with the command: " + command);
	}
	} catch(IOException e) {
	Slog.w(LOG_TAG, "Connection error: ", e);
	} finally {
	if (in != null) {
	try {
	in.close();

	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	if (mClient != null) {
	try {
	mClient.close();
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	}
	}

	public void windowsChanged() {
	synchronized(this) {
	mNeedWindowListUpdate = true;
	notifyAll();
	}
	}

	public void focusChanged() {
	synchronized(this) {
	mNeedFocusedWindowUpdate = true;
	notifyAll();
	}
	}

	private boolean windowManagerAutolistLoop() {
	mWindowManager.addWindowChangeListener(this);
	BufferedWriter out = null;
	try {
	out = new BufferedWriter(new OutputStreamWriter(mClient.getOutputStream()));
	while (!Thread.interrupted()) {
	boolean needWindowListUpdate = false;
	boolean needFocusedWindowUpdate = false;
	synchronized (this) {
	while (!mNeedWindowListUpdate && !mNeedFocusedWindowUpdate) {
	wait();
	}
	if (mNeedWindowListUpdate) {
	mNeedWindowListUpdate = false;
	needWindowListUpdate = true;
	}
	if (mNeedFocusedWindowUpdate) {
	mNeedFocusedWindowUpdate = false;
	needFocusedWindowUpdate = true;
	}
	}
	if(needWindowListUpdate) {
	out.write("LIST UPDATE\n");
	out.flush();
	}
	if(needFocusedWindowUpdate) {
	out.write("FOCUS UPDATE\n");
	out.flush();
	}
	}
	} catch (Exception e) {
	Slog.w(LOG_TAG, "Connection error: ", e);
	} finally {
	if (out != null) {
	try {
	out.close();
	} catch (IOException e) {
	}
	}
	mWindowManager.removeWindowChangeListener(this);
	}
	return true;
	}
	}
	}