--- /dev/null
+/* Copyright 2020 Alex Tanskanen for Cendio AB
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ */
+
+/*
+ * Based on xf86-input-evdev
+ *
+ * Copyright 1990,91 by Thomas Roell, Dinkelscherben, Germany.
+ * Copyright 1993 by David Dawes <dawes@xfree86.org>
+ * Copyright 2002 by SuSE Linux AG, Author: Egbert Eich
+ * Copyright 1994-2002 by The XFree86 Project, Inc.
+ * Copyright 2002 by Paul Elliott
+ * (Ported from xf86-input-mouse, above copyrights taken from there)
+ * Copyright © 2008 University of South Australia
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of the authors
+ * not be used in advertising or publicity pertaining to distribution of the
+ * software without specific, written prior permission. The authors make no
+ * representations about the suitability of this software for any
+ * purpose. It is provided "as is" without express or implied
+ * warranty.
+ *
+ * THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+
+#include <rfb/Exception.h>
+
+#include "parameters.h"
+#include "i18n.h"
+#include "EmulateMB.h"
+
+/*
+ * Lets create a simple finite-state machine for 3 button emulation:
+ *
+ * We track buttons 1 and 3 (left and right). There are 11 states:
+ * 0 ground - initial state
+ * 1 delayed left - left pressed, waiting for right
+ * 2 delayed right - right pressed, waiting for left
+ * 3 pressed middle - right and left pressed, emulated middle sent
+ * 4 pressed left - left pressed and sent
+ * 5 pressed right - right pressed and sent
+ * 6 released left - left released after emulated middle
+ * 7 released right - right released after emulated middle
+ * 8 repressed left - left pressed after released left
+ * 9 repressed right - right pressed after released right
+ * 10 pressed both - both pressed, not emulating middle
+ *
+ * At each state, we need handlers for the following events
+ * 0: no buttons down
+ * 1: left button down
+ * 2: right button down
+ * 3: both buttons down
+ * 4: emulate3Timeout passed without a button change
+ * Note that button events are not deltas, they are the set of buttons being
+ * pressed now. It's possible (ie, mouse hardware does it) to go from (eg)
+ * left down to right down without anything in between, so all cases must be
+ * handled.
+ *
+ * a handler consists of three values:
+ * 0: action1
+ * 1: action2
+ * 2: new emulation state
+ *
+ * action > 0: ButtonPress
+ * action = 0: nothing
+ * action < 0: ButtonRelease
+ *
+ * The comment preceeding each section is the current emulation state.
+ * The comments to the right are of the form
+ * <button state> (<events>) -> <new emulation state>
+ * which should be read as
+ * If the buttons are in <button state>, generate <events> then go to
+ * <new emulation state>.
+ */
+static const signed char stateTab[11][5][3] = {
+/* 0 ground */
+ {
+ { 0, 0, 0 }, /* nothing -> ground (no change) */
+ { 0, 0, 1 }, /* left -> delayed left */
+ { 0, 0, 2 }, /* right -> delayed right */
+ { 2, 0, 3 }, /* left & right (middle press) -> pressed middle */
+ { 0, 0, -1 } /* timeout N/A */
+ },
+/* 1 delayed left */
+ {
+ { 1, -1, 0 }, /* nothing (left event) -> ground */
+ { 0, 0, 1 }, /* left -> delayed left (no change) */
+ { 1, -1, 2 }, /* right (left event) -> delayed right */
+ { 2, 0, 3 }, /* left & right (middle press) -> pressed middle */
+ { 1, 0, 4 }, /* timeout (left press) -> pressed left */
+ },
+/* 2 delayed right */
+ {
+ { 3, -3, 0 }, /* nothing (right event) -> ground */
+ { 3, -3, 1 }, /* left (right event) -> delayed left (no change) */
+ { 0, 0, 2 }, /* right -> delayed right (no change) */
+ { 2, 0, 3 }, /* left & right (middle press) -> pressed middle */
+ { 3, 0, 5 }, /* timeout (right press) -> pressed right */
+ },
+/* 3 pressed middle */
+ {
+ { -2, 0, 0 }, /* nothing (middle release) -> ground */
+ { 0, 0, 7 }, /* left -> released right */
+ { 0, 0, 6 }, /* right -> released left */
+ { 0, 0, 3 }, /* left & right -> pressed middle (no change) */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 4 pressed left */
+ {
+ { -1, 0, 0 }, /* nothing (left release) -> ground */
+ { 0, 0, 4 }, /* left -> pressed left (no change) */
+ { -1, 0, 2 }, /* right (left release) -> delayed right */
+ { 3, 0, 10 }, /* left & right (right press) -> pressed both */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 5 pressed right */
+ {
+ { -3, 0, 0 }, /* nothing (right release) -> ground */
+ { -3, 0, 1 }, /* left (right release) -> delayed left */
+ { 0, 0, 5 }, /* right -> pressed right (no change) */
+ { 1, 0, 10 }, /* left & right (left press) -> pressed both */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 6 released left */
+ {
+ { -2, 0, 0 }, /* nothing (middle release) -> ground */
+ { -2, 0, 1 }, /* left (middle release) -> delayed left */
+ { 0, 0, 6 }, /* right -> released left (no change) */
+ { 1, 0, 8 }, /* left & right (left press) -> repressed left */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 7 released right */
+ {
+ { -2, 0, 0 }, /* nothing (middle release) -> ground */
+ { 0, 0, 7 }, /* left -> released right (no change) */
+ { -2, 0, 2 }, /* right (middle release) -> delayed right */
+ { 3, 0, 9 }, /* left & right (right press) -> repressed right */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 8 repressed left */
+ {
+ { -2, -1, 0 }, /* nothing (middle release, left release) -> ground */
+ { -2, 0, 4 }, /* left (middle release) -> pressed left */
+ { -1, 0, 6 }, /* right (left release) -> released left */
+ { 0, 0, 8 }, /* left & right -> repressed left (no change) */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 9 repressed right */
+ {
+ { -2, -3, 0 }, /* nothing (middle release, right release) -> ground */
+ { -3, 0, 7 }, /* left (right release) -> released right */
+ { -2, 0, 5 }, /* right (middle release) -> pressed right */
+ { 0, 0, 9 }, /* left & right -> repressed right (no change) */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+/* 10 pressed both */
+ {
+ { -1, -3, 0 }, /* nothing (left release, right release) -> ground */
+ { -3, 0, 4 }, /* left (right release) -> pressed left */
+ { -1, 0, 5 }, /* right (left release) -> pressed right */
+ { 0, 0, 10 }, /* left & right -> pressed both (no change) */
+ { 0, 0, -1 }, /* timeout N/A */
+ },
+};
+
+EmulateMB::EmulateMB()
+ : state(0), emulatedButtonMask(0), timer(this)
+{
+}
+
+void EmulateMB::filterPointerEvent(const rfb::Point& pos, int buttonMask)
+{
+ int btstate;
+ int action1, action2;
+ int lastState;
+
+ if (!emulateMiddleButton) {
+ sendPointerEvent(pos, buttonMask);
+ return;
+ }
+
+ lastButtonMask = buttonMask;
+ lastPos = pos;
+
+ btstate = 0;
+
+ if (buttonMask & 0x1)
+ btstate |= 0x1;
+
+ if (buttonMask & 0x4)
+ btstate |= 0x2;
+
+ if ((state > 10) || (state < 0))
+ throw rfb::Exception(_("Invalid state for 3 button emulation"));
+
+ action1 = stateTab[state][btstate][0];
+ if (action1 != 0)
+ sendAction(pos, buttonMask, action1);
+
+ action2 = stateTab[state][btstate][1];
+ if (action2 != 0)
+ sendAction(pos, buttonMask, action2);
+
+ if ((action1 == 0) && (action2 == 0)) {
+ buttonMask &= ~0x5;
+ buttonMask |= emulatedButtonMask;
+ sendPointerEvent(pos, buttonMask);
+ }
+
+ lastState = state;
+ state = stateTab[state][btstate][2];
+
+ if (lastState != state) {
+ timer.stop();
+
+ if (stateTab[state][4][2] >= 0)
+ timer.start(50);
+ }
+}
+
+bool EmulateMB::handleTimeout(rfb::Timer *t)
+{
+ int action1, action2;
+
+ if (&timer != t)
+ return false;
+
+ if ((state > 10) || (state < 0))
+ throw rfb::Exception(_("Invalid state for 3 button emulation"));
+
+ assert(stateTab[state][4][2] >= 0);
+
+ action1 = stateTab[state][4][0];
+ if (action1 != 0)
+ sendAction(lastPos, lastButtonMask, action1);
+
+ action2 = stateTab[state][4][1];
+ if (action2 != 0)
+ sendAction(lastPos, lastButtonMask, action2);
+
+ state = stateTab[state][4][2];
+
+ return false;
+}
+
+void EmulateMB::sendAction(const rfb::Point& pos, int buttonMask, int action)
+{
+ assert(action != 0);
+
+ if (action < 0)
+ emulatedButtonMask &= ~(1 << ((-action) - 1));
+ else
+ emulatedButtonMask |= (1 << (action - 1));
+
+ buttonMask &= ~0x5;
+ buttonMask |= emulatedButtonMask;
+ sendPointerEvent(pos, buttonMask);
+}
projects / tigervnc.git / commitdiff