ECMA48Terminal.java

   1 /**
   2  * Jexer - Java Text User Interface
   3  *
   4  * License: LGPLv3 or later
   5  *
   6  * This module is licensed under the GNU Lesser General Public License
   7  * Version 3.  Please see the file "COPYING" in this directory for more
   8  * information about the GNU Lesser General Public License Version 3.
   9  *
  10  *     Copyright (C) 2015  Kevin Lamonte
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public License
  14  * as published by the Free Software Foundation; either version 3 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this program; if not, see
  24  * http://www.gnu.org/licenses/, or write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  26  * 02110-1301 USA
  27  *
  28  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  29  * @version 1
  30  */
  31 package jexer.io;
  32
  33 import java.io.BufferedReader;
  34 import java.io.FileDescriptor;
  35 import java.io.FileInputStream;
  36 import java.io.InputStream;
  37 import java.io.InputStreamReader;
  38 import java.io.IOException;
  39 import java.io.OutputStream;
  40 import java.io.OutputStreamWriter;
  41 import java.io.PrintWriter;
  42 import java.io.Reader;
  43 import java.io.UnsupportedEncodingException;
  44 import java.util.ArrayList;
  45 import java.util.Date;
  46 import java.util.List;
  47 import java.util.LinkedList;
  48
  49 import jexer.bits.Color;
  50 import jexer.event.TInputEvent;
  51 import jexer.event.TKeypressEvent;
  52 import jexer.event.TMouseEvent;
  53 import jexer.event.TResizeEvent;
  54 import jexer.session.SessionInfo;
  55 import jexer.session.TSessionInfo;
  56 import jexer.session.TTYSessionInfo;
  57 import static jexer.TKeypress.*;
  58
  59 /**
  60  * This class reads keystrokes and mouse events and emits output to ANSI
  61  * X3.64 / ECMA-48 type terminals e.g. xterm, linux, vt100, ansi.sys, etc.
  62  */
  63 public final class ECMA48Terminal implements Runnable {
  64
  65     /**
  66      * The session information.
  67      */
  68     private SessionInfo sessionInfo;
  69
  70     /**
  71      * Getter for sessionInfo.
  72      *
  73      * @return the SessionInfo
  74      */
  75     public SessionInfo getSessionInfo() {
  76         return sessionInfo;
  77     }
  78
  79     /**
  80      * The event queue, filled up by a thread reading on input.
  81      */
  82     private List<TInputEvent> eventQueue;
  83
  84     /**
  85      * If true, we want the reader thread to exit gracefully.
  86      */
  87     private boolean stopReaderThread;
  88
  89     /**
  90      * The reader thread.
  91      */
  92     private Thread readerThread;
  93
  94     /**
  95      * Parameters being collected.  E.g. if the string is \033[1;3m, then
  96      * params[0] will be 1 and params[1] will be 3.
  97      */
  98     private ArrayList<String> params;
  99
 100     /**
 101      * States in the input parser.
 102      */
 103     private enum ParseState {
 104         GROUND,
 105         ESCAPE,
 106         ESCAPE_INTERMEDIATE,
 107         CSI_ENTRY,
 108         CSI_PARAM,
 109         // CSI_INTERMEDIATE,
 110         MOUSE,
 111         MOUSE_SGR,
 112     }
 113
 114     /**
 115      * Current parsing state.
 116      */
 117     private ParseState state;
 118
 119     /**
 120      * The time we entered ESCAPE.  If we get a bare escape without a code
 121      * following it, this is used to return that bare escape.
 122      */
 123     private long escapeTime;
 124
 125     /**
 126      * The time we last checked the window size.  We try not to spawn stty
 127      * more than once per second.
 128      */
 129     private long windowSizeTime;
 130
 131     /**
 132      * true if mouse1 was down.  Used to report mouse1 on the release event.
 133      */
 134     private boolean mouse1;
 135
 136     /**
 137      * true if mouse2 was down.  Used to report mouse2 on the release event.
 138      */
 139     private boolean mouse2;
 140
 141     /**
 142      * true if mouse3 was down.  Used to report mouse3 on the release event.
 143      */
 144     private boolean mouse3;
 145
 146     /**
 147      * Cache the cursor visibility value so we only emit the sequence when we
 148      * need to.
 149      */
 150     private boolean cursorOn = true;
 151
 152     /**
 153      * Cache the last window size to figure out if a TResizeEvent needs to be
 154      * generated.
 155      */
 156     private TResizeEvent windowResize = null;
 157
 158     /**
 159      * If true, then we changed System.in and need to change it back.
 160      */
 161     private boolean setRawMode;
 162
 163     /**
 164      * The terminal's input.  If an InputStream is not specified in the
 165      * constructor, then this InputStreamReader will be bound to System.in
 166      * with UTF-8 encoding.
 167      */
 168     private Reader input;
 169
 170     /**
 171      * The terminal's raw InputStream.  If an InputStream is not specified in
 172      * the constructor, then this InputReader will be bound to System.in.
 173      * This is used by run() to see if bytes are available() before calling
 174      * (Reader)input.read().
 175      */
 176     private InputStream inputStream;
 177
 178     /**
 179      * The terminal's output.  If an OutputStream is not specified in the
 180      * constructor, then this PrintWriter will be bound to System.out with
 181      * UTF-8 encoding.
 182      */
 183     private PrintWriter output;
 184
 185     /**
 186      * The listening object that run() wakes up on new input.
 187      */
 188     private Object listener;
 189
 190     /**
 191      * Get the output writer.
 192      *
 193      * @return the Writer
 194      */
 195     public PrintWriter getOutput() {
 196         return output;
 197     }
 198
 199     /**
 200      * Check if there are events in the queue.
 201      *
 202      * @return if true, getEvents() has something to return to the backend
 203      */
 204     public boolean hasEvents() {
 205         synchronized (eventQueue) {
 206             return (eventQueue.size() > 0);
 207         }
 208     }
 209
 210     /**
 211      * Call 'stty' to set cooked mode.
 212      *
 213      * <p>Actually executes '/bin/sh -c stty sane cooked &lt; /dev/tty'
 214      */
 215     private void sttyCooked() {
 216         doStty(false);
 217     }
 218
 219     /**
 220      * Call 'stty' to set raw mode.
 221      *
 222      * <p>Actually executes '/bin/sh -c stty -ignbrk -brkint -parmrk -istrip
 223      * -inlcr -igncr -icrnl -ixon -opost -echo -echonl -icanon -isig -iexten
 224      * -parenb cs8 min 1 &lt; /dev/tty'
 225      */
 226     private void sttyRaw() {
 227         doStty(true);
 228     }
 229
 230     /**
 231      * Call 'stty' to set raw or cooked mode.
 232      *
 233      * @param mode if true, set raw mode, otherwise set cooked mode
 234      */
 235     private void doStty(final boolean mode) {
 236         String [] cmdRaw = {
 237             "/bin/sh", "-c", "stty -ignbrk -brkint -parmrk -istrip -inlcr -igncr -icrnl -ixon -opost -echo -echonl -icanon -isig -iexten -parenb cs8 min 1 < /dev/tty"
 238         };
 239         String [] cmdCooked = {
 240             "/bin/sh", "-c", "stty sane cooked < /dev/tty"
 241         };
 242         try {
 243             Process process;
 244             if (mode) {
 245                 process = Runtime.getRuntime().exec(cmdRaw);
 246             } else {
 247                 process = Runtime.getRuntime().exec(cmdCooked);
 248             }
 249             BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream(), "UTF-8"));
 250             String line = in.readLine();
 251             if ((line != null) && (line.length() > 0)) {
 252                 System.err.println("WEIRD?! Normal output from stty: " + line);
 253             }
 254             while (true) {
 255                 BufferedReader err = new BufferedReader(new InputStreamReader(process.getErrorStream(), "UTF-8"));
 256                 line = err.readLine();
 257                 if ((line != null) && (line.length() > 0)) {
 258                     System.err.println("Error output from stty: " + line);
 259                 }
 260                 try {
 261                     process.waitFor();
 262                     break;
 263                 } catch (InterruptedException e) {
 264                     e.printStackTrace();
 265                 }
 266             }
 267             int rc = process.exitValue();
 268             if (rc != 0) {
 269                 System.err.println("stty returned error code: " + rc);
 270             }
 271         } catch (IOException e) {
 272             e.printStackTrace();
 273         }
 274     }
 275
 276     /**
 277      * Constructor sets up state for getEvent().
 278      *
 279      * @param listener the object this backend needs to wake up when new
 280      * input comes in
 281      * @param input an InputStream connected to the remote user, or null for
 282      * System.in.  If System.in is used, then on non-Windows systems it will
 283      * be put in raw mode; shutdown() will (blindly!) put System.in in cooked
 284      * mode.  input is always converted to a Reader with UTF-8 encoding.
 285      * @param output an OutputStream connected to the remote user, or null
 286      * for System.out.  output is always converted to a Writer with UTF-8
 287      * encoding.
 288      * @throws UnsupportedEncodingException if an exception is thrown when
 289      * creating the InputStreamReader
 290      */
 291     public ECMA48Terminal(final Object listener, final InputStream input,
 292         final OutputStream output) throws UnsupportedEncodingException {
 293
 294         reset();
 295         mouse1           = false;
 296         mouse2           = false;
 297         mouse3           = false;
 298         stopReaderThread = false;
 299         this.listener    = listener;
 300
 301         if (input == null) {
 302             // inputStream = System.in;
 303             inputStream = new FileInputStream(FileDescriptor.in);
 304             sttyRaw();
 305             setRawMode = true;
 306         } else {
 307             inputStream = input;
 308         }
 309         this.input = new InputStreamReader(inputStream, "UTF-8");
 310
 311         if (input instanceof SessionInfo) {
 312             // This is a TelnetInputStream that exposes window size and
 313             // environment variables from the telnet layer.
 314             sessionInfo = (SessionInfo) input;
 315         }
 316         if (sessionInfo == null) {
 317             if (input == null) {
 318                 // Reading right off the tty
 319                 sessionInfo = new TTYSessionInfo();
 320             } else {
 321                 sessionInfo = new TSessionInfo();
 322             }
 323         }
 324
 325         if (output == null) {
 326             this.output = new PrintWriter(new OutputStreamWriter(System.out,
 327                     "UTF-8"));
 328         } else {
 329             this.output = new PrintWriter(new OutputStreamWriter(output,
 330                     "UTF-8"));
 331         }
 332
 333         // Enable mouse reporting and metaSendsEscape
 334         this.output.printf("%s%s", mouse(true), xtermMetaSendsEscape(true));
 335         this.output.flush();
 336
 337         // Hang onto the window size
 338         windowResize = new TResizeEvent(TResizeEvent.Type.SCREEN,
 339             sessionInfo.getWindowWidth(), sessionInfo.getWindowHeight());
 340
 341         // Spin up the input reader
 342         eventQueue = new LinkedList<TInputEvent>();
 343         readerThread = new Thread(this);
 344         readerThread.start();
 345     }
 346
 347     /**
 348      * Restore terminal to normal state.
 349      */
 350     public void shutdown() {
 351
 352         // System.err.println("=== shutdown() ==="); System.err.flush();
 353
 354         // Tell the reader thread to stop looking at input
 355         stopReaderThread = true;
 356         try {
 357             readerThread.join();
 358         } catch (InterruptedException e) {
 359             e.printStackTrace();
 360         }
 361
 362         // Disable mouse reporting and show cursor
 363         output.printf("%s%s%s", mouse(false), cursor(true), normal());
 364         output.flush();
 365
 366         if (setRawMode) {
 367             sttyCooked();
 368             setRawMode = false;
 369             // We don't close System.in/out
 370         } else {
 371             // Shut down the streams, this should wake up the reader thread
 372             // and make it exit.
 373             try {
 374                 if (input != null) {
 375                     input.close();
 376                     input = null;
 377                 }
 378                 if (output != null) {
 379                     output.close();
 380                     output = null;
 381                 }
 382             } catch (IOException e) {
 383                 e.printStackTrace();
 384             }
 385         }
 386     }
 387
 388     /**
 389      * Flush output.
 390      */
 391     public void flush() {
 392         output.flush();
 393     }
 394
 395     /**
 396      * Reset keyboard/mouse input parser.
 397      */
 398     private void reset() {
 399         state = ParseState.GROUND;
 400         params = new ArrayList<String>();
 401         params.clear();
 402         params.add("");
 403     }
 404
 405     /**
 406      * Produce a control character or one of the special ones (ENTER, TAB,
 407      * etc.).
 408      *
 409      * @param ch Unicode code point
 410      * @param alt if true, set alt on the TKeypress
 411      * @return one TKeypress event, either a control character (e.g. isKey ==
 412      * false, ch == 'A', ctrl == true), or a special key (e.g. isKey == true,
 413      * fnKey == ESC)
 414      */
 415     private TKeypressEvent controlChar(final char ch, final boolean alt) {
 416         // System.err.printf("controlChar: %02x\n", ch);
 417
 418         switch (ch) {
 419         case 0x0D:
 420             // Carriage return --> ENTER
 421             return new TKeypressEvent(kbEnter, alt, false, false);
 422         case 0x0A:
 423             // Linefeed --> ENTER
 424             return new TKeypressEvent(kbEnter, alt, false, false);
 425         case 0x1B:
 426             // ESC
 427             return new TKeypressEvent(kbEsc, alt, false, false);
 428         case '\t':
 429             // TAB
 430             return new TKeypressEvent(kbTab, alt, false, false);
 431         default:
 432             // Make all other control characters come back as the alphabetic
 433             // character with the ctrl field set.  So SOH would be 'A' +
 434             // ctrl.
 435             return new TKeypressEvent(false, 0, (char)(ch + 0x40),
 436                 alt, true, false);
 437         }
 438     }
 439
 440     /**
 441      * Produce special key from CSI Pn ; Pm ; ... ~
 442      *
 443      * @return one KEYPRESS event representing a special key
 444      */
 445     private TInputEvent csiFnKey() {
 446         int key = 0;
 447         int modifier = 0;
 448         if (params.size() > 0) {
 449             key = Integer.parseInt(params.get(0));
 450         }
 451         if (params.size() > 1) {
 452             modifier = Integer.parseInt(params.get(1));
 453         }
 454         boolean alt = false;
 455         boolean ctrl = false;
 456         boolean shift = false;
 457
 458         switch (modifier) {
 459         case 0:
 460             // No modifier
 461             break;
 462         case 2:
 463             // Shift
 464             shift = true;
 465             break;
 466         case 3:
 467             // Alt
 468             alt = true;
 469             break;
 470         case 5:
 471             // Ctrl
 472             ctrl = true;
 473             break;
 474         default:
 475             // Unknown modifier, bail out
 476             return null;
 477         }
 478
 479         switch (key) {
 480         case 1:
 481             return new TKeypressEvent(kbHome, alt, ctrl, shift);
 482         case 2:
 483             return new TKeypressEvent(kbIns, alt, ctrl, shift);
 484         case 3:
 485             return new TKeypressEvent(kbDel, alt, ctrl, shift);
 486         case 4:
 487             return new TKeypressEvent(kbEnd, alt, ctrl, shift);
 488         case 5:
 489             return new TKeypressEvent(kbPgUp, alt, ctrl, shift);
 490         case 6:
 491             return new TKeypressEvent(kbPgDn, alt, ctrl, shift);
 492         case 15:
 493             return new TKeypressEvent(kbF5, alt, ctrl, shift);
 494         case 17:
 495             return new TKeypressEvent(kbF6, alt, ctrl, shift);
 496         case 18:
 497             return new TKeypressEvent(kbF7, alt, ctrl, shift);
 498         case 19:
 499             return new TKeypressEvent(kbF8, alt, ctrl, shift);
 500         case 20:
 501             return new TKeypressEvent(kbF9, alt, ctrl, shift);
 502         case 21:
 503             return new TKeypressEvent(kbF10, alt, ctrl, shift);
 504         case 23:
 505             return new TKeypressEvent(kbF11, alt, ctrl, shift);
 506         case 24:
 507             return new TKeypressEvent(kbF12, alt, ctrl, shift);
 508         default:
 509             // Unknown
 510             return null;
 511         }
 512     }
 513
 514     /**
 515      * Produce mouse events based on "Any event tracking" and UTF-8
 516      * coordinates.  See
 517      * http://invisible-island.net/xterm/ctlseqs/ctlseqs.html#Mouse%20Tracking
 518      *
 519      * @return a MOUSE_MOTION, MOUSE_UP, or MOUSE_DOWN event
 520      */
 521     private TInputEvent parseMouse() {
 522         int buttons = params.get(0).charAt(0) - 32;
 523         int x = params.get(0).charAt(1) - 32 - 1;
 524         int y = params.get(0).charAt(2) - 32 - 1;
 525
 526         // Clamp X and Y to the physical screen coordinates.
 527         if (x >= windowResize.getWidth()) {
 528             x = windowResize.getWidth() - 1;
 529         }
 530         if (y >= windowResize.getHeight()) {
 531             y = windowResize.getHeight() - 1;
 532         }
 533
 534         TMouseEvent.Type eventType = TMouseEvent.Type.MOUSE_DOWN;
 535         boolean eventMouse1 = false;
 536         boolean eventMouse2 = false;
 537         boolean eventMouse3 = false;
 538         boolean eventMouseWheelUp = false;
 539         boolean eventMouseWheelDown = false;
 540
 541         // System.err.printf("buttons: %04x\r\n", buttons);
 542
 543         switch (buttons) {
 544         case 0:
 545             eventMouse1 = true;
 546             mouse1 = true;
 547             break;
 548         case 1:
 549             eventMouse2 = true;
 550             mouse2 = true;
 551             break;
 552         case 2:
 553             eventMouse3 = true;
 554             mouse3 = true;
 555             break;
 556         case 3:
 557             // Release or Move
 558             if (!mouse1 && !mouse2 && !mouse3) {
 559                 eventType = TMouseEvent.Type.MOUSE_MOTION;
 560             } else {
 561                 eventType = TMouseEvent.Type.MOUSE_UP;
 562             }
 563             if (mouse1) {
 564                 mouse1 = false;
 565                 eventMouse1 = true;
 566             }
 567             if (mouse2) {
 568                 mouse2 = false;
 569                 eventMouse2 = true;
 570             }
 571             if (mouse3) {
 572                 mouse3 = false;
 573                 eventMouse3 = true;
 574             }
 575             break;
 576
 577         case 32:
 578             // Dragging with mouse1 down
 579             eventMouse1 = true;
 580             mouse1 = true;
 581             eventType = TMouseEvent.Type.MOUSE_MOTION;
 582             break;
 583
 584         case 33:
 585             // Dragging with mouse2 down
 586             eventMouse2 = true;
 587             mouse2 = true;
 588             eventType = TMouseEvent.Type.MOUSE_MOTION;
 589             break;
 590
 591         case 34:
 592             // Dragging with mouse3 down
 593             eventMouse3 = true;
 594             mouse3 = true;
 595             eventType = TMouseEvent.Type.MOUSE_MOTION;
 596             break;
 597
 598         case 96:
 599             // Dragging with mouse2 down after wheelUp
 600             eventMouse2 = true;
 601             mouse2 = true;
 602             eventType = TMouseEvent.Type.MOUSE_MOTION;
 603             break;
 604
 605         case 97:
 606             // Dragging with mouse2 down after wheelDown
 607             eventMouse2 = true;
 608             mouse2 = true;
 609             eventType = TMouseEvent.Type.MOUSE_MOTION;
 610             break;
 611
 612         case 64:
 613             eventMouseWheelUp = true;
 614             break;
 615
 616         case 65:
 617             eventMouseWheelDown = true;
 618             break;
 619
 620         default:
 621             // Unknown, just make it motion
 622             eventType = TMouseEvent.Type.MOUSE_MOTION;
 623             break;
 624         }
 625         return new TMouseEvent(eventType, x, y, x, y,
 626             eventMouse1, eventMouse2, eventMouse3,
 627             eventMouseWheelUp, eventMouseWheelDown);
 628     }
 629
 630     /**
 631      * Produce mouse events based on "Any event tracking" and SGR
 632      * coordinates.  See
 633      * http://invisible-island.net/xterm/ctlseqs/ctlseqs.html#Mouse%20Tracking
 634      *
 635      * @param release if true, this was a release ('m')
 636      * @return a MOUSE_MOTION, MOUSE_UP, or MOUSE_DOWN event
 637      */
 638     private TInputEvent parseMouseSGR(final boolean release) {
 639         // SGR extended coordinates - mode 1006
 640         if (params.size() < 3) {
 641             // Invalid position, bail out.
 642             return null;
 643         }
 644         int buttons = Integer.parseInt(params.get(0));
 645         int x = Integer.parseInt(params.get(1)) - 1;
 646         int y = Integer.parseInt(params.get(2)) - 1;
 647
 648         // Clamp X and Y to the physical screen coordinates.
 649         if (x >= windowResize.getWidth()) {
 650             x = windowResize.getWidth() - 1;
 651         }
 652         if (y >= windowResize.getHeight()) {
 653             y = windowResize.getHeight() - 1;
 654         }
 655
 656         TMouseEvent.Type eventType = TMouseEvent.Type.MOUSE_DOWN;
 657         boolean eventMouse1 = false;
 658         boolean eventMouse2 = false;
 659         boolean eventMouse3 = false;
 660         boolean eventMouseWheelUp = false;
 661         boolean eventMouseWheelDown = false;
 662
 663         if (release) {
 664             eventType = TMouseEvent.Type.MOUSE_UP;
 665         }
 666
 667         switch (buttons) {
 668         case 0:
 669             eventMouse1 = true;
 670             break;
 671         case 1:
 672             eventMouse2 = true;
 673             break;
 674         case 2:
 675             eventMouse3 = true;
 676             break;
 677         case 35:
 678             // Motion only, no buttons down
 679             eventType = TMouseEvent.Type.MOUSE_MOTION;
 680             break;
 681
 682         case 32:
 683             // Dragging with mouse1 down
 684             eventMouse1 = true;
 685             eventType = TMouseEvent.Type.MOUSE_MOTION;
 686             break;
 687
 688         case 33:
 689             // Dragging with mouse2 down
 690             eventMouse2 = true;
 691             eventType = TMouseEvent.Type.MOUSE_MOTION;
 692             break;
 693
 694         case 34:
 695             // Dragging with mouse3 down
 696             eventMouse3 = true;
 697             eventType = TMouseEvent.Type.MOUSE_MOTION;
 698             break;
 699
 700         case 96:
 701             // Dragging with mouse2 down after wheelUp
 702             eventMouse2 = true;
 703             eventType = TMouseEvent.Type.MOUSE_MOTION;
 704             break;
 705
 706         case 97:
 707             // Dragging with mouse2 down after wheelDown
 708             eventMouse2 = true;
 709             eventType = TMouseEvent.Type.MOUSE_MOTION;
 710             break;
 711
 712         case 64:
 713             eventMouseWheelUp = true;
 714             break;
 715
 716         case 65:
 717             eventMouseWheelDown = true;
 718             break;
 719
 720         default:
 721             // Unknown, bail out
 722             return null;
 723         }
 724         return new TMouseEvent(eventType, x, y, x, y,
 725             eventMouse1, eventMouse2, eventMouse3,
 726             eventMouseWheelUp, eventMouseWheelDown);
 727     }
 728
 729     /**
 730      * Return any events in the IO queue.
 731      *
 732      * @param queue list to append new events to
 733      */
 734     public void getEvents(final List<TInputEvent> queue) {
 735         synchronized (eventQueue) {
 736             if (eventQueue.size() > 0) {
 737                 synchronized (queue) {
 738                     queue.addAll(eventQueue);
 739                 }
 740                 eventQueue.clear();
 741             }
 742         }
 743     }
 744
 745     /**
 746      * Return any events in the IO queue due to timeout.
 747      *
 748      * @param queue list to append new events to
 749      */
 750     private void getIdleEvents(final List<TInputEvent> queue) {
 751         Date now = new Date();
 752
 753         // Check for new window size
 754         long windowSizeDelay = now.getTime() - windowSizeTime;
 755         if (windowSizeDelay > 1000) {
 756             sessionInfo.queryWindowSize();
 757             int newWidth = sessionInfo.getWindowWidth();
 758             int newHeight = sessionInfo.getWindowHeight();
 759             if ((newWidth != windowResize.getWidth())
 760                 || (newHeight != windowResize.getHeight())
 761             ) {
 762                 TResizeEvent event = new TResizeEvent(TResizeEvent.Type.SCREEN,
 763                     newWidth, newHeight);
 764                 windowResize = new TResizeEvent(TResizeEvent.Type.SCREEN,
 765                     newWidth, newHeight);
 766                 queue.add(event);
 767             }
 768             windowSizeTime = now.getTime();
 769         }
 770
 771         // ESCDELAY type timeout
 772         if (state == ParseState.ESCAPE) {
 773             long escDelay = now.getTime() - escapeTime;
 774             if (escDelay > 100) {
 775                 // After 0.1 seconds, assume a true escape character
 776                 queue.add(controlChar((char)0x1B, false));
 777                 reset();
 778             }
 779         }
 780     }
 781
 782     /**
 783      * Parses the next character of input to see if an InputEvent is
 784      * fully here.
 785      *
 786      * @param events list to append new events to
 787      * @param ch Unicode code point
 788      */
 789     private void processChar(final List<TInputEvent> events, final char ch) {
 790
 791         // ESCDELAY type timeout
 792         Date now = new Date();
 793         if (state == ParseState.ESCAPE) {
 794             long escDelay = now.getTime() - escapeTime;
 795             if (escDelay > 250) {
 796                 // After 0.25 seconds, assume a true escape character
 797                 events.add(controlChar((char)0x1B, false));
 798                 reset();
 799             }
 800         }
 801
 802         // TKeypress fields
 803         boolean ctrl = false;
 804         boolean alt = false;
 805         boolean shift = false;
 806
 807         // System.err.printf("state: %s ch %c\r\n", state, ch);
 808
 809         switch (state) {
 810         case GROUND:
 811
 812             if (ch == 0x1B) {
 813                 state = ParseState.ESCAPE;
 814                 escapeTime = now.getTime();
 815                 return;
 816             }
 817
 818             if (ch <= 0x1F) {
 819                 // Control character
 820                 events.add(controlChar(ch, false));
 821                 reset();
 822                 return;
 823             }
 824
 825             if (ch >= 0x20) {
 826                 // Normal character
 827                 events.add(new TKeypressEvent(false, 0, ch,
 828                         false, false, false));
 829                 reset();
 830                 return;
 831             }
 832
 833             break;
 834
 835         case ESCAPE:
 836             if (ch <= 0x1F) {
 837                 // ALT-Control character
 838                 events.add(controlChar(ch, true));
 839                 reset();
 840                 return;
 841             }
 842
 843             if (ch == 'O') {
 844                 // This will be one of the function keys
 845                 state = ParseState.ESCAPE_INTERMEDIATE;
 846                 return;
 847             }
 848
 849             // '[' goes to CSI_ENTRY
 850             if (ch == '[') {
 851                 state = ParseState.CSI_ENTRY;
 852                 return;
 853             }
 854
 855             // Everything else is assumed to be Alt-keystroke
 856             if ((ch >= 'A') && (ch <= 'Z')) {
 857                 shift = true;
 858             }
 859             alt = true;
 860             events.add(new TKeypressEvent(false, 0, ch, alt, ctrl, shift));
 861             reset();
 862             return;
 863
 864         case ESCAPE_INTERMEDIATE:
 865             if ((ch >= 'P') && (ch <= 'S')) {
 866                 // Function key
 867                 switch (ch) {
 868                 case 'P':
 869                     events.add(new TKeypressEvent(kbF1));
 870                     break;
 871                 case 'Q':
 872                     events.add(new TKeypressEvent(kbF2));
 873                     break;
 874                 case 'R':
 875                     events.add(new TKeypressEvent(kbF3));
 876                     break;
 877                 case 'S':
 878                     events.add(new TKeypressEvent(kbF4));
 879                     break;
 880                 default:
 881                     break;
 882                 }
 883                 reset();
 884                 return;
 885             }
 886
 887             // Unknown keystroke, ignore
 888             reset();
 889             return;
 890
 891         case CSI_ENTRY:
 892             // Numbers - parameter values
 893             if ((ch >= '0') && (ch <= '9')) {
 894                 params.set(params.size() - 1,
 895                     params.get(params.size() - 1) + ch);
 896                 state = ParseState.CSI_PARAM;
 897                 return;
 898             }
 899             // Parameter separator
 900             if (ch == ';') {
 901                 params.add("");
 902                 return;
 903             }
 904
 905             if ((ch >= 0x30) && (ch <= 0x7E)) {
 906                 switch (ch) {
 907                 case 'A':
 908                     // Up
 909                     if (params.size() > 1) {
 910                         if (params.get(1).equals("2")) {
 911                             shift = true;
 912                         }
 913                         if (params.get(1).equals("5")) {
 914                             ctrl = true;
 915                         }
 916                         if (params.get(1).equals("3")) {
 917                             alt = true;
 918                         }
 919                     }
 920                     events.add(new TKeypressEvent(kbUp, alt, ctrl, shift));
 921                     reset();
 922                     return;
 923                 case 'B':
 924                     // Down
 925                     if (params.size() > 1) {
 926                         if (params.get(1).equals("2")) {
 927                             shift = true;
 928                         }
 929                         if (params.get(1).equals("5")) {
 930                             ctrl = true;
 931                         }
 932                         if (params.get(1).equals("3")) {
 933                             alt = true;
 934                         }
 935                     }
 936                     events.add(new TKeypressEvent(kbDown, alt, ctrl, shift));
 937                     reset();
 938                     return;
 939                 case 'C':
 940                     // Right
 941                     if (params.size() > 1) {
 942                         if (params.get(1).equals("2")) {
 943                             shift = true;
 944                         }
 945                         if (params.get(1).equals("5")) {
 946                             ctrl = true;
 947                         }
 948                         if (params.get(1).equals("3")) {
 949                             alt = true;
 950                         }
 951                     }
 952                     events.add(new TKeypressEvent(kbRight, alt, ctrl, shift));
 953                     reset();
 954                     return;
 955                 case 'D':
 956                     // Left
 957                     if (params.size() > 1) {
 958                         if (params.get(1).equals("2")) {
 959                             shift = true;
 960                         }
 961                         if (params.get(1).equals("5")) {
 962                             ctrl = true;
 963                         }
 964                         if (params.get(1).equals("3")) {
 965                             alt = true;
 966                         }
 967                     }
 968                     events.add(new TKeypressEvent(kbLeft, alt, ctrl, shift));
 969                     reset();
 970                     return;
 971                 case 'H':
 972                     // Home
 973                     events.add(new TKeypressEvent(kbHome));
 974                     reset();
 975                     return;
 976                 case 'F':
 977                     // End
 978                     events.add(new TKeypressEvent(kbEnd));
 979                     reset();
 980                     return;
 981                 case 'Z':
 982                     // CBT - Cursor backward X tab stops (default 1)
 983                     events.add(new TKeypressEvent(kbBackTab));
 984                     reset();
 985                     return;
 986                 case 'M':
 987                     // Mouse position
 988                     state = ParseState.MOUSE;
 989                     return;
 990                 case '<':
 991                     // Mouse position, SGR (1006) coordinates
 992                     state = ParseState.MOUSE_SGR;
 993                     return;
 994                 default:
 995                     break;
 996                 }
 997             }
 998
 999             // Unknown keystroke, ignore
1000             reset();
1001             return;
1002
1003         case MOUSE_SGR:
1004             // Numbers - parameter values
1005             if ((ch >= '0') && (ch <= '9')) {
1006                 params.set(params.size() - 1,
1007                     params.get(params.size() - 1) + ch);
1008                 return;
1009             }
1010             // Parameter separator
1011             if (ch == ';') {
1012                 params.add("");
1013                 return;
1014             }
1015
1016             switch (ch) {
1017             case 'M':
1018                 // Generate a mouse press event
1019                 TInputEvent event = parseMouseSGR(false);
1020                 if (event != null) {
1021                     events.add(event);
1022                 }
1023                 reset();
1024                 return;
1025             case 'm':
1026                 // Generate a mouse release event
1027                 event = parseMouseSGR(true);
1028                 if (event != null) {
1029                     events.add(event);
1030                 }
1031                 reset();
1032                 return;
1033             default:
1034                 break;
1035             }
1036
1037             // Unknown keystroke, ignore
1038             reset();
1039             return;
1040
1041         case CSI_PARAM:
1042             // Numbers - parameter values
1043             if ((ch >= '0') && (ch <= '9')) {
1044                 params.set(params.size() - 1,
1045                     params.get(params.size() - 1) + ch);
1046                 state = ParseState.CSI_PARAM;
1047                 return;
1048             }
1049             // Parameter separator
1050             if (ch == ';') {
1051                 params.add("");
1052                 return;
1053             }
1054
1055             if (ch == '~') {
1056                 events.add(csiFnKey());
1057                 reset();
1058                 return;
1059             }
1060
1061             if ((ch >= 0x30) && (ch <= 0x7E)) {
1062                 switch (ch) {
1063                 case 'A':
1064                     // Up
1065                     if (params.size() > 1) {
1066                         if (params.get(1).equals("2")) {
1067                             shift = true;
1068                         }
1069                         if (params.get(1).equals("5")) {
1070                             ctrl = true;
1071                         }
1072                         if (params.get(1).equals("3")) {
1073                             alt = true;
1074                         }
1075                     }
1076                     events.add(new TKeypressEvent(kbUp, alt, ctrl, shift));
1077                     reset();
1078                     return;
1079                 case 'B':
1080                     // Down
1081                     if (params.size() > 1) {
1082                         if (params.get(1).equals("2")) {
1083                             shift = true;
1084                         }
1085                         if (params.get(1).equals("5")) {
1086                             ctrl = true;
1087                         }
1088                         if (params.get(1).equals("3")) {
1089                             alt = true;
1090                         }
1091                     }
1092                     events.add(new TKeypressEvent(kbDown, alt, ctrl, shift));
1093                     reset();
1094                     return;
1095                 case 'C':
1096                     // Right
1097                     if (params.size() > 1) {
1098                         if (params.get(1).equals("2")) {
1099                             shift = true;
1100                         }
1101                         if (params.get(1).equals("5")) {
1102                             ctrl = true;
1103                         }
1104                         if (params.get(1).equals("3")) {
1105                             alt = true;
1106                         }
1107                     }
1108                     events.add(new TKeypressEvent(kbRight, alt, ctrl, shift));
1109                     reset();
1110                     return;
1111                 case 'D':
1112                     // Left
1113                     if (params.size() > 1) {
1114                         if (params.get(1).equals("2")) {
1115                             shift = true;
1116                         }
1117                         if (params.get(1).equals("5")) {
1118                             ctrl = true;
1119                         }
1120                         if (params.get(1).equals("3")) {
1121                             alt = true;
1122                         }
1123                     }
1124                     events.add(new TKeypressEvent(kbLeft, alt, ctrl, shift));
1125                     reset();
1126                     return;
1127                 default:
1128                     break;
1129                 }
1130             }
1131
1132             // Unknown keystroke, ignore
1133             reset();
1134             return;
1135
1136         case MOUSE:
1137             params.set(0, params.get(params.size() - 1) + ch);
1138             if (params.get(0).length() == 3) {
1139                 // We have enough to generate a mouse event
1140                 events.add(parseMouse());
1141                 reset();
1142             }
1143             return;
1144
1145         default:
1146             break;
1147         }
1148
1149         // This "should" be impossible to reach
1150         return;
1151     }
1152
1153     /**
1154      * Tell (u)xterm that we want alt- keystrokes to send escape + character
1155      * rather than set the 8th bit.  Anyone who wants UTF8 should want this
1156      * enabled.
1157      *
1158      * @param on if true, enable metaSendsEscape
1159      * @return the string to emit to xterm
1160      */
1161     private String xtermMetaSendsEscape(final boolean on) {
1162         if (on) {
1163             return "\033[?1036h\033[?1034l";
1164         }
1165         return "\033[?1036l";
1166     }
1167
1168     /**
1169      * Convert a list of SGR parameters into a full escape sequence.  This
1170      * also eliminates a trailing ';' which would otherwise reset everything
1171      * to white-on-black not-bold.
1172      *
1173      * @param str string of parameters, e.g. "31;1;"
1174      * @return the string to emit to an ANSI / ECMA-style terminal,
1175      * e.g. "\033[31;1m"
1176      */
1177     private String addHeaderSGR(String str) {
1178         if (str.length() > 0) {
1179             // Nix any trailing ';' because that resets all attributes
1180             while (str.endsWith(":")) {
1181                 str = str.substring(0, str.length() - 1);
1182             }
1183         }
1184         return "\033[" + str + "m";
1185     }
1186
1187     /**
1188      * Create a SGR parameter sequence for a single color change.  Note
1189      * package private access.
1190      *
1191      * @param color one of the Color.WHITE, Color.BLUE, etc. constants
1192      * @param foreground if true, this is a foreground color
1193      * @return the string to emit to an ANSI / ECMA-style terminal,
1194      * e.g. "\033[42m"
1195      */
1196     String color(final Color color, final boolean foreground) {
1197         return color(color, foreground, true);
1198     }
1199
1200     /**
1201      * Create a SGR parameter sequence for a single color change.
1202      *
1203      * @param color one of the Color.WHITE, Color.BLUE, etc. constants
1204      * @param foreground if true, this is a foreground color
1205      * @param header if true, make the full header, otherwise just emit the
1206      * color parameter e.g. "42;"
1207      * @return the string to emit to an ANSI / ECMA-style terminal,
1208      * e.g. "\033[42m"
1209      */
1210     private String color(final Color color, final boolean foreground,
1211         final boolean header) {
1212
1213         int ecmaColor = color.getValue();
1214
1215         // Convert Color.* values to SGR numerics
1216         if (foreground) {
1217             ecmaColor += 30;
1218         } else {
1219             ecmaColor += 40;
1220         }
1221
1222         if (header) {
1223             return String.format("\033[%dm", ecmaColor);
1224         } else {
1225             return String.format("%d;", ecmaColor);
1226         }
1227     }
1228
1229     /**
1230      * Create a SGR parameter sequence for both foreground and background
1231      * color change.  Note package private access.
1232      *
1233      * @param foreColor one of the Color.WHITE, Color.BLUE, etc. constants
1234      * @param backColor one of the Color.WHITE, Color.BLUE, etc. constants
1235      * @return the string to emit to an ANSI / ECMA-style terminal,
1236      * e.g. "\033[31;42m"
1237      */
1238     String color(final Color foreColor, final Color backColor) {
1239         return color(foreColor, backColor, true);
1240     }
1241
1242     /**
1243      * Create a SGR parameter sequence for both foreground and
1244      * background color change.
1245      *
1246      * @param foreColor one of the Color.WHITE, Color.BLUE, etc. constants
1247      * @param backColor one of the Color.WHITE, Color.BLUE, etc. constants
1248      * @param header if true, make the full header, otherwise just emit the
1249      * color parameter e.g. "31;42;"
1250      * @return the string to emit to an ANSI / ECMA-style terminal,
1251      * e.g. "\033[31;42m"
1252      */
1253     private String color(final Color foreColor, final Color backColor,
1254         final boolean header) {
1255
1256         int ecmaForeColor = foreColor.getValue();
1257         int ecmaBackColor = backColor.getValue();
1258
1259         // Convert Color.* values to SGR numerics
1260         ecmaBackColor += 40;
1261         ecmaForeColor += 30;
1262
1263         if (header) {
1264             return String.format("\033[%d;%dm", ecmaForeColor, ecmaBackColor);
1265         } else {
1266             return String.format("%d;%d;", ecmaForeColor, ecmaBackColor);
1267         }
1268     }
1269
1270     /**
1271      * Create a SGR parameter sequence for foreground, background, and
1272      * several attributes.  This sequence first resets all attributes to
1273      * default, then sets attributes as per the parameters.  Note package
1274      * private access.
1275      *
1276      * @param foreColor one of the Color.WHITE, Color.BLUE, etc. constants
1277      * @param backColor one of the Color.WHITE, Color.BLUE, etc. constants
1278      * @param bold if true, set bold
1279      * @param reverse if true, set reverse
1280      * @param blink if true, set blink
1281      * @param underline if true, set underline
1282      * @return the string to emit to an ANSI / ECMA-style terminal,
1283      * e.g. "\033[0;1;31;42m"
1284      */
1285     String color(final Color foreColor, final Color backColor,
1286         final boolean bold, final boolean reverse, final boolean blink,
1287         final boolean underline) {
1288
1289         int ecmaForeColor = foreColor.getValue();
1290         int ecmaBackColor = backColor.getValue();
1291
1292         // Convert Color.* values to SGR numerics
1293         ecmaBackColor += 40;
1294         ecmaForeColor += 30;
1295
1296         StringBuilder sb = new StringBuilder();
1297         if        (  bold &&  reverse &&  blink && !underline ) {
1298             sb.append("\033[0;1;7;5;");
1299         } else if (  bold &&  reverse && !blink && !underline ) {
1300             sb.append("\033[0;1;7;");
1301         } else if ( !bold &&  reverse &&  blink && !underline ) {
1302             sb.append("\033[0;7;5;");
1303         } else if (  bold && !reverse &&  blink && !underline ) {
1304             sb.append("\033[0;1;5;");
1305         } else if (  bold && !reverse && !blink && !underline ) {
1306             sb.append("\033[0;1;");
1307         } else if ( !bold &&  reverse && !blink && !underline ) {
1308             sb.append("\033[0;7;");
1309         } else if ( !bold && !reverse &&  blink && !underline) {
1310             sb.append("\033[0;5;");
1311         } else if (  bold &&  reverse &&  blink &&  underline ) {
1312             sb.append("\033[0;1;7;5;4;");
1313         } else if (  bold &&  reverse && !blink &&  underline ) {
1314             sb.append("\033[0;1;7;4;");
1315         } else if ( !bold &&  reverse &&  blink &&  underline ) {
1316             sb.append("\033[0;7;5;4;");
1317         } else if (  bold && !reverse &&  blink &&  underline ) {
1318             sb.append("\033[0;1;5;4;");
1319         } else if (  bold && !reverse && !blink &&  underline ) {
1320             sb.append("\033[0;1;4;");
1321         } else if ( !bold &&  reverse && !blink &&  underline ) {
1322             sb.append("\033[0;7;4;");
1323         } else if ( !bold && !reverse &&  blink &&  underline) {
1324             sb.append("\033[0;5;4;");
1325         } else if ( !bold && !reverse && !blink &&  underline) {
1326             sb.append("\033[0;4;");
1327         } else {
1328             assert (!bold && !reverse && !blink && !underline);
1329             sb.append("\033[0;");
1330         }
1331         sb.append(String.format("%d;%dm", ecmaForeColor, ecmaBackColor));
1332         return sb.toString();
1333     }
1334
1335     /**
1336      * Create a SGR parameter sequence for enabling reverse color.
1337      *
1338      * @param on if true, turn on reverse
1339      * @return the string to emit to an ANSI / ECMA-style terminal,
1340      * e.g. "\033[7m"
1341      */
1342     private String reverse(final boolean on) {
1343         if (on) {
1344             return "\033[7m";
1345         }
1346         return "\033[27m";
1347     }
1348
1349     /**
1350      * Create a SGR parameter sequence to reset to defaults.  Note package
1351      * private access.
1352      *
1353      * @return the string to emit to an ANSI / ECMA-style terminal,
1354      * e.g. "\033[0m"
1355      */
1356     String normal() {
1357         return normal(true);
1358     }
1359
1360     /**
1361      * Create a SGR parameter sequence to reset to defaults.
1362      *
1363      * @param header if true, make the full header, otherwise just emit the
1364      * bare parameter e.g. "0;"
1365      * @return the string to emit to an ANSI / ECMA-style terminal,
1366      * e.g. "\033[0m"
1367      */
1368     private String normal(final boolean header) {
1369         if (header) {
1370             return "\033[0;37;40m";
1371         }
1372         return "0;37;40";
1373     }
1374
1375     /**
1376      * Create a SGR parameter sequence for enabling boldface.
1377      *
1378      * @param on if true, turn on bold
1379      * @return the string to emit to an ANSI / ECMA-style terminal,
1380      * e.g. "\033[1m"
1381      */
1382     private String bold(final boolean on) {
1383         return bold(on, true);
1384     }
1385
1386     /**
1387      * Create a SGR parameter sequence for enabling boldface.
1388      *
1389      * @param on if true, turn on bold
1390      * @param header if true, make the full header, otherwise just emit the
1391      * bare parameter e.g. "1;"
1392      * @return the string to emit to an ANSI / ECMA-style terminal,
1393      * e.g. "\033[1m"
1394      */
1395     private String bold(final boolean on, final boolean header) {
1396         if (header) {
1397             if (on) {
1398                 return "\033[1m";
1399             }
1400             return "\033[22m";
1401         }
1402         if (on) {
1403             return "1;";
1404         }
1405         return "22;";
1406     }
1407
1408     /**
1409      * Create a SGR parameter sequence for enabling blinking text.
1410      *
1411      * @param on if true, turn on blink
1412      * @return the string to emit to an ANSI / ECMA-style terminal,
1413      * e.g. "\033[5m"
1414      */
1415     private String blink(final boolean on) {
1416         return blink(on, true);
1417     }
1418
1419     /**
1420      * Create a SGR parameter sequence for enabling blinking text.
1421      *
1422      * @param on if true, turn on blink
1423      * @param header if true, make the full header, otherwise just emit the
1424      * bare parameter e.g. "5;"
1425      * @return the string to emit to an ANSI / ECMA-style terminal,
1426      * e.g. "\033[5m"
1427      */
1428     private String blink(final boolean on, final boolean header) {
1429         if (header) {
1430             if (on) {
1431                 return "\033[5m";
1432             }
1433             return "\033[25m";
1434         }
1435         if (on) {
1436             return "5;";
1437         }
1438         return "25;";
1439     }
1440
1441     /**
1442      * Create a SGR parameter sequence for enabling underline / underscored
1443      * text.
1444      *
1445      * @param on if true, turn on underline
1446      * @return the string to emit to an ANSI / ECMA-style terminal,
1447      * e.g. "\033[4m"
1448      */
1449     private String underline(final boolean on) {
1450         if (on) {
1451             return "\033[4m";
1452         }
1453         return "\033[24m";
1454     }
1455
1456     /**
1457      * Create a SGR parameter sequence for enabling the visible cursor.  Note
1458      * package private access.
1459      *
1460      * @param on if true, turn on cursor
1461      * @return the string to emit to an ANSI / ECMA-style terminal
1462      */
1463     String cursor(final boolean on) {
1464         if (on && !cursorOn) {
1465             cursorOn = true;
1466             return "\033[?25h";
1467         }
1468         if (!on && cursorOn) {
1469             cursorOn = false;
1470             return "\033[?25l";
1471         }
1472         return "";
1473     }
1474
1475     /**
1476      * Clear the entire screen.  Because some terminals use back-color-erase,
1477      * set the color to white-on-black beforehand.
1478      *
1479      * @return the string to emit to an ANSI / ECMA-style terminal
1480      */
1481     public String clearAll() {
1482         return "\033[0;37;40m\033[2J";
1483     }
1484
1485     /**
1486      * Clear the line from the cursor (inclusive) to the end of the screen.
1487      * Because some terminals use back-color-erase, set the color to
1488      * white-on-black beforehand.  Note package private access.
1489      *
1490      * @return the string to emit to an ANSI / ECMA-style terminal
1491      */
1492     String clearRemainingLine() {
1493         return "\033[0;37;40m\033[K";
1494     }
1495
1496     /**
1497      * Clear the line up the cursor (inclusive).  Because some terminals use
1498      * back-color-erase, set the color to white-on-black beforehand.
1499      *
1500      * @return the string to emit to an ANSI / ECMA-style terminal
1501      */
1502     private String clearPreceedingLine() {
1503         return "\033[0;37;40m\033[1K";
1504     }
1505
1506     /**
1507      * Clear the line.  Because some terminals use back-color-erase, set the
1508      * color to white-on-black beforehand.
1509      *
1510      * @return the string to emit to an ANSI / ECMA-style terminal
1511      */
1512     private String clearLine() {
1513         return "\033[0;37;40m\033[2K";
1514     }
1515
1516     /**
1517      * Move the cursor to the top-left corner.
1518      *
1519      * @return the string to emit to an ANSI / ECMA-style terminal
1520      */
1521     private String home() {
1522         return "\033[H";
1523     }
1524
1525     /**
1526      * Move the cursor to (x, y).  Note package private access.
1527      *
1528      * @param x column coordinate.  0 is the left-most column.
1529      * @param y row coordinate.  0 is the top-most row.
1530      * @return the string to emit to an ANSI / ECMA-style terminal
1531      */
1532     String gotoXY(final int x, final int y) {
1533         return String.format("\033[%d;%dH", y + 1, x + 1);
1534     }
1535
1536     /**
1537      * Tell (u)xterm that we want to receive mouse events based on "Any event
1538      * tracking", UTF-8 coordinates, and then SGR coordinates.  Ideally we
1539      * will end up with SGR coordinates with UTF-8 coordinates as a fallback.
1540      * See
1541      * http://invisible-island.net/xterm/ctlseqs/ctlseqs.html#Mouse%20Tracking
1542      *
1543      * Note that this also sets the alternate/primary screen buffer.
1544      *
1545      * @param on If true, enable mouse report and use the alternate screen
1546      * buffer.  If false disable mouse reporting and use the primary screen
1547      * buffer.
1548      * @return the string to emit to xterm
1549      */
1550     private String mouse(final boolean on) {
1551         if (on) {
1552             return "\033[?1003;1005;1006h\033[?1049h";
1553         }
1554         return "\033[?1003;1006;1005l\033[?1049l";
1555     }
1556
1557     /**
1558      * Read function runs on a separate thread.
1559      */
1560     public void run() {
1561         boolean done = false;
1562         // available() will often return > 1, so we need to read in chunks to
1563         // stay caught up.
1564         char [] readBuffer = new char[128];
1565         List<TInputEvent> events = new LinkedList<TInputEvent>();
1566
1567         while (!done && !stopReaderThread) {
1568             try {
1569                 // We assume that if inputStream has bytes available, then
1570                 // input won't block on read().
1571                 int n = inputStream.available();
1572                 if (n > 0) {
1573                     if (readBuffer.length < n) {
1574                         // The buffer wasn't big enough, make it huger
1575                         readBuffer = new char[readBuffer.length * 2];
1576                     }
1577
1578                     int rc = input.read(readBuffer, 0, readBuffer.length);
1579                     // System.err.printf("read() %d", rc); System.err.flush();
1580                     if (rc == -1) {
1581                         // This is EOF
1582                         done = true;
1583                     } else {
1584                         for (int i = 0; i < rc; i++) {
1585                             int ch = readBuffer[i];
1586                             processChar(events, (char)ch);
1587                         }
1588                         getIdleEvents(events);
1589                         if (events.size() > 0) {
1590                             // Add to the queue for the backend thread to
1591                             // be able to obtain.
1592                             synchronized (eventQueue) {
1593                                 eventQueue.addAll(events);
1594                             }
1595                             synchronized (listener) {
1596                                 listener.notifyAll();
1597                             }
1598                             events.clear();
1599                         }
1600                     }
1601                 } else {
1602                     getIdleEvents(events);
1603                     if (events.size() > 0) {
1604                         synchronized (eventQueue) {
1605                             eventQueue.addAll(events);
1606                         }
1607                         events.clear();
1608                         synchronized (listener) {
1609                             listener.notifyAll();
1610                         }
1611                     }
1612
1613                     // Wait 10 millis for more data
1614                     Thread.sleep(10);
1615                 }
1616                 // System.err.println("end while loop"); System.err.flush();
1617             } catch (InterruptedException e) {
1618                 // SQUASH
1619             } catch (IOException e) {
1620                 e.printStackTrace();
1621                 done = true;
1622             }
1623         } // while ((done == false) && (stopReaderThread == false))
1624         // System.err.println("*** run() exiting..."); System.err.flush();
1625     }
1626
1627 }