rfbproto.java

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    b[15] = (byte) greenShift;
    b[16] = (byte) blueShift;

    os.write(b);
  }


  //
  // Write a FixColourMapEntries message.  The values in the red, green and
  // blue arrays are from 0 to 65535.
  //

  void writeFixColourMapEntries(int firstColour, int nColours,
				int[] red, int[] green, int[] blue)
       throws IOException
  {
    byte[] b = new byte[6 + nColours * 6];

    b[0] = (byte) FixColourMapEntries;
    b[2] = (byte) ((firstColour >> 8) & 0xff);
    b[3] = (byte) (firstColour & 0xff);
    b[4] = (byte) ((nColours >> 8) & 0xff);
    b[5] = (byte) (nColours & 0xff);

    for (int i = 0; i < nColours; i++) {
      b[6 + i * 6]     = (byte) ((red[i] >> 8) & 0xff);
      b[6 + i * 6 + 1] = (byte) (red[i] & 0xff);
      b[6 + i * 6 + 2] = (byte) ((green[i] >> 8) & 0xff);
      b[6 + i * 6 + 3] = (byte) (green[i] & 0xff);
      b[6 + i * 6 + 4] = (byte) ((blue[i] >> 8) & 0xff);
      b[6 + i * 6 + 5] = (byte) (blue[i] & 0xff);
    }
 
    os.write(b);
  }


  //
  // Write a SetEncodings message
  //

  void writeSetEncodings(int[] encs, int len) throws IOException {
    byte[] b = new byte[4 + 4 * len];

    b[0] = (byte) SetEncodings;
    b[2] = (byte) ((len >> 8) & 0xff);
    b[3] = (byte) (len & 0xff);

    for (int i = 0; i < len; i++) {
      b[4 + 4 * i] = (byte) ((encs[i] >> 24) & 0xff);
      b[5 + 4 * i] = (byte) ((encs[i] >> 16) & 0xff);
      b[6 + 4 * i] = (byte) ((encs[i] >> 8) & 0xff);
      b[7 + 4 * i] = (byte) (encs[i] & 0xff);
    }

    os.write(b);
  }


  //
  // Write a ClientCutText message
  //

  void writeClientCutText(String text) throws IOException {
    byte[] b = new byte[8 + text.length()];

    b[0] = (byte) ClientCutText;
    b[4] = (byte) ((text.length() >> 24) & 0xff);
    b[5] = (byte) ((text.length() >> 16) & 0xff);
    b[6] = (byte) ((text.length() >> 8) & 0xff);
    b[7] = (byte) (text.length() & 0xff);

    System.arraycopy(text.getBytes(), 0, b, 8, text.length());

    os.write(b);
  }


  //
  // A buffer for putting pointer and keyboard events before being sent.  This
  // is to ensure that multiple RFB events generated from a single Java Event 
  // will all be sent in a single network packet.  The maximum possible
  // length is 4 modifier down events, a single key event followed by 4
  // modifier up events i.e. 9 key events or 72 bytes.
  //

  byte[] eventBuf = new byte[72];
  int eventBufLen;


  // Useful shortcuts for modifier masks.

  final static int CTRL_MASK  = InputEvent.CTRL_MASK;
  final static int SHIFT_MASK = InputEvent.SHIFT_MASK;
  final static int META_MASK  = InputEvent.META_MASK;
  final static int ALT_MASK   = InputEvent.ALT_MASK;


  //
  // Write a pointer event message.  We may need to send modifier key events
  // around it to set the correct modifier state.
  //

  int pointerMask = 0;

  void writePointerEvent(MouseEvent evt) throws IOException {
    int modifiers = evt.getModifiers();

    int mask2 = 2;
    int mask3 = 4;
    if (viewer.options.reverseMouseButtons2And3) {
      mask2 = 4;
      mask3 = 2;
    }

    // Note: For some reason, AWT does not set BUTTON1_MASK on left
    // button presses. Here we think that it was the left button if
    // modifiers do not include BUTTON2_MASK or BUTTON3_MASK.

    if (evt.getID() == MouseEvent.MOUSE_PRESSED) {
      if ((modifiers & InputEvent.BUTTON2_MASK) != 0) {
        pointerMask = mask2;
        modifiers &= ~ALT_MASK;
      } else if ((modifiers & InputEvent.BUTTON3_MASK) != 0) {
        pointerMask = mask3;
        modifiers &= ~META_MASK;
      } else {
        pointerMask = 1;
      }
    } else if (evt.getID() == MouseEvent.MOUSE_RELEASED) {
      pointerMask = 0;
      if ((modifiers & InputEvent.BUTTON2_MASK) != 0) {
        modifiers &= ~ALT_MASK;
      } else if ((modifiers & InputEvent.BUTTON3_MASK) != 0) {
        modifiers &= ~META_MASK;
      }
    }

    eventBufLen = 0;
    writeModifierKeyEvents(modifiers);

    int x = evt.getX();
    int y = evt.getY();

    if (x < 0) x = 0;
    if (y < 0) y = 0;

    eventBuf[eventBufLen++] = (byte) PointerEvent;
    eventBuf[eventBufLen++] = (byte) pointerMask;
    eventBuf[eventBufLen++] = (byte) ((x >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (x & 0xff);
    eventBuf[eventBufLen++] = (byte) ((y >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (y & 0xff);

    //
    // Always release all modifiers after an "up" event
    //

    if (pointerMask == 0) {
      writeModifierKeyEvents(0);
    }

    os.write(eventBuf, 0, eventBufLen);
  }


  //
  // Write a key event message.  We may need to send modifier key events
  // around it to set the correct modifier state.  Also we need to translate
  // from the Java key values to the X keysym values used by the RFB protocol.
  //

  void writeKeyEvent(KeyEvent evt) throws IOException {

    int keyChar = evt.getKeyChar();

    //
    // Ignore event if only modifiers were pressed.
    //

    // Some JVMs return 0 instead of CHAR_UNDEFINED in getKeyChar().
    if (keyChar == 0)
      keyChar = KeyEvent.CHAR_UNDEFINED;

    if (keyChar == KeyEvent.CHAR_UNDEFINED) {
      int code = evt.getKeyCode();
      if (code == KeyEvent.VK_CONTROL || code == KeyEvent.VK_SHIFT ||
          code == KeyEvent.VK_META || code == KeyEvent.VK_ALT)
        return;
    }

    //
    // Key press or key release?
    //

    boolean down = (evt.getID() == KeyEvent.KEY_PRESSED);

    int key;
    if (evt.isActionKey()) {

      //
      // An action key should be one of the following.
      // If not then just ignore the event.
      //

      switch(evt.getKeyCode()) {
      case KeyEvent.VK_HOME:      key = 0xff50; break;
      case KeyEvent.VK_LEFT:      key = 0xff51; break;
      case KeyEvent.VK_UP:        key = 0xff52; break;
      case KeyEvent.VK_RIGHT:     key = 0xff53; break;
      case KeyEvent.VK_DOWN:      key = 0xff54; break;
      case KeyEvent.VK_PAGE_UP:   key = 0xff55; break;
      case KeyEvent.VK_PAGE_DOWN: key = 0xff56; break;
      case KeyEvent.VK_END:       key = 0xff57; break;
      case KeyEvent.VK_INSERT:    key = 0xff63; break;
      case KeyEvent.VK_F1:        key = 0xffbe; break;
      case KeyEvent.VK_F2:        key = 0xffbf; break;
      case KeyEvent.VK_F3:        key = 0xffc0; break;
      case KeyEvent.VK_F4:        key = 0xffc1; break;
      case KeyEvent.VK_F5:        key = 0xffc2; break;
      case KeyEvent.VK_F6:        key = 0xffc3; break;
      case KeyEvent.VK_F7:        key = 0xffc4; break;
      case KeyEvent.VK_F8:        key = 0xffc5; break;
      case KeyEvent.VK_F9:        key = 0xffc6; break;
      case KeyEvent.VK_F10:       key = 0xffc7; break;
      case KeyEvent.VK_F11:       key = 0xffc8; break;
      case KeyEvent.VK_F12:       key = 0xffc9; break;
      default:
        return;
      }

    } else {

      //
      // A "normal" key press.  Ordinary ASCII characters go straight through.
      // For CTRL-<letter>, CTRL is sent separately so just send <letter>.
      // Backspace, tab, return, escape and delete have special keysyms.
      // Anything else we ignore.
      //

      key = keyChar;

      if (key < 0x20) {
        if (evt.isControlDown()) {
          key += 0x60;
        } else {
          switch(key) {
          case KeyEvent.VK_BACK_SPACE: key = 0xff08; break;
          case KeyEvent.VK_TAB:        key = 0xff09; break;
          case KeyEvent.VK_ENTER:      key = 0xff0d; break;
          case KeyEvent.VK_ESCAPE:     key = 0xff1b; break;
          }
        }
      } else if (key == 0x7f) {
	// Delete
	key = 0xffff;
      } else if (key > 0xff) {
	// JDK1.1 on X incorrectly passes some keysyms straight through,
	// so we do too.  JDK1.1.4 seems to have fixed this.
	// The keysyms passed are 0xff00 .. XK_BackSpace .. XK_Delete
	// Also, we pass through foreign currency keysyms (0x20a0..0x20af).
	if ((key < 0xff00 || key > 0xffff) &&
	    !(key >= 0x20a0 && key <= 0x20af))
	  return;
      }
    }

    // Fake keyPresses for keys that only generates keyRelease events
    if ((key == 0xe5) || (key == 0xc5) || // XK_aring / XK_Aring
	(key == 0xe4) || (key == 0xc4) || // XK_adiaeresis / XK_Adiaeresis
	(key == 0xf6) || (key == 0xd6) || // XK_odiaeresis / XK_Odiaeresis
	(key == 0xa7) || (key == 0xbd) || // XK_section / XK_onehalf
	(key == 0xa3)) {                  // XK_sterling
      // Make sure we do not send keypress events twice on platforms
      // with correct JVMs (those that actually report KeyPress for all
      // keys)	
      if (down)
	brokenKeyPressed = true;

      if (!down && !brokenKeyPressed) {
	// We've got a release event for this key, but haven't received
        // a press. Fake it. 
	eventBufLen = 0;
	writeModifierKeyEvents(evt.getModifiers());
	writeKeyEvent(key, true);
	os.write(eventBuf, 0, eventBufLen);
      }

      if (!down)
	brokenKeyPressed = false;  
    }

    eventBufLen = 0;
    writeModifierKeyEvents(evt.getModifiers());
    writeKeyEvent(key, down);

    // Always release all modifiers after an "up" event
    if (!down)
      writeModifierKeyEvents(0);

    os.write(eventBuf, 0, eventBufLen);
  }


  //
  // Add a raw key event with the given X keysym to eventBuf.
  //

  void writeKeyEvent(int keysym, boolean down) {
    eventBuf[eventBufLen++] = (byte) KeyboardEvent;
    eventBuf[eventBufLen++] = (byte) (down ? 1 : 0);
    eventBuf[eventBufLen++] = (byte) 0;
    eventBuf[eventBufLen++] = (byte) 0;
    eventBuf[eventBufLen++] = (byte) ((keysym >> 24) & 0xff);
    eventBuf[eventBufLen++] = (byte) ((keysym >> 16) & 0xff);
    eventBuf[eventBufLen++] = (byte) ((keysym >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (keysym & 0xff);
  }


  //
  // Write key events to set the correct modifier state.
  //

  int oldModifiers = 0;

  void writeModifierKeyEvents(int newModifiers) {
    if ((newModifiers & CTRL_MASK) != (oldModifiers & CTRL_MASK))
      writeKeyEvent(0xffe3, (newModifiers & CTRL_MASK) != 0);

    if ((newModifiers & SHIFT_MASK) != (oldModifiers & SHIFT_MASK))
      writeKeyEvent(0xffe1, (newModifiers & SHIFT_MASK) != 0);

    if ((newModifiers & META_MASK) != (oldModifiers & META_MASK))
      writeKeyEvent(0xffe7, (newModifiers & META_MASK) != 0);

    if ((newModifiers & ALT_MASK) != (oldModifiers & ALT_MASK))
      writeKeyEvent(0xffe9, (newModifiers & ALT_MASK) != 0);

    oldModifiers = newModifiers;
  }


  //
  // Compress and write the data into the recorded session file. This
  // method assumes the recording is on (rec != null).
  //

  void recordCompressedData(byte[] data, int off, int len) throws IOException {
    Deflater deflater = new Deflater();
    deflater.setInput(data, off, len);
    int bufSize = len + len / 100 + 12;
    byte[] buf = new byte[bufSize];
    deflater.finish();
    int compressedSize = deflater.deflate(buf);
    recordCompactLen(compressedSize);
    rec.write(buf, 0, compressedSize);
  }

  void recordCompressedData(byte[] data) throws IOException {
    recordCompressedData(data, 0, data.length);
  }

  //
  // Write an integer in compact representation (1..3 bytes) into the
  // recorded session file. This method assumes the recording is on
  // (rec != null).
  //

  void recordCompactLen(int len) throws IOException {
    byte[] buf = new byte[3];
    int bytes = 0;
    buf[bytes++] = (byte)(len & 0x7F);
    if (len > 0x7F) {
      buf[bytes-1] |= 0x80;
      buf[bytes++] = (byte)(len >> 7 & 0x7F);
      if (len > 0x3FFF) {
	buf[bytes-1] |= 0x80;
	buf[bytes++] = (byte)(len >> 14 & 0xFF);
      }
    }
    rec.write(buf, 0, bytes);
  }

  public void startTiming() {
    timing = true;

    // Carry over up to 1s worth of previous rate for smoothing.

    if (timeWaitedIn100us > 10000) {
      timedKbits = timedKbits * 10000 / timeWaitedIn100us;
      timeWaitedIn100us = 10000;
    }
  }

  public void stopTiming() {
    timing = false; 
    if (timeWaitedIn100us < timedKbits/2)
      timeWaitedIn100us = timedKbits/2; // upper limit 20Mbit/s
  }

  public long kbitsPerSecond() {
    return timedKbits * 10000 / timeWaitedIn100us;
  }

  public long timeWaited() {
    return timeWaitedIn100us;
  }

  public void readFully(byte b[]) throws IOException {
    readFully(b, 0, b.length);
  }

  public void readFully(byte b[], int off, int len) throws IOException {
    long before = 0;
    if (timing)
      before = System.currentTimeMillis();

    is.readFully(b, off, len);

    if (timing) {
      long after = System.currentTimeMillis();
      long newTimeWaited = (after - before) * 10;
      int newKbits = len * 8 / 1000;

      // limit rate to between 10kbit/s and 40Mbit/s

      if (newTimeWaited > newKbits*1000) newTimeWaited = newKbits*1000;
      if (newTimeWaited < newKbits/4)    newTimeWaited = newKbits/4;

      timeWaitedIn100us += newTimeWaited;
      timedKbits += newKbits;
    }
  }

}