src/jexer/TTerminalWidget.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2019 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer;
  30
  31 import java.awt.Font;
  32 import java.awt.FontMetrics;
  33 import java.awt.Graphics2D;
  34 import java.awt.image.BufferedImage;
  35
  36 import java.io.InputStream;
  37 import java.io.IOException;
  38 import java.lang.reflect.Field;
  39 import java.text.MessageFormat;
  40 import java.util.ArrayList;
  41 import java.util.HashMap;
  42 import java.util.List;
  43 import java.util.Map;
  44 import java.util.ResourceBundle;
  45
  46 import jexer.backend.ECMA48Terminal;
  47 import jexer.backend.GlyphMaker;
  48 import jexer.backend.MultiScreen;
  49 import jexer.backend.SwingTerminal;
  50 import jexer.bits.Cell;
  51 import jexer.bits.CellAttributes;
  52 import jexer.event.TKeypressEvent;
  53 import jexer.event.TMenuEvent;
  54 import jexer.event.TMouseEvent;
  55 import jexer.event.TResizeEvent;
  56 import jexer.menu.TMenu;
  57 import jexer.tterminal.DisplayLine;
  58 import jexer.tterminal.DisplayListener;
  59 import jexer.tterminal.ECMA48;
  60 import static jexer.TKeypress.*;
  61
  62 /**
  63  * TTerminalWidget exposes a ECMA-48 / ANSI X3.64 style terminal in a widget.
  64  */
  65 public class TTerminalWidget extends TScrollableWidget
  66                              implements DisplayListener {
  67
  68     /**
  69      * Translated strings.
  70      */
  71     private static final ResourceBundle i18n = ResourceBundle.getBundle(TTerminalWidget.class.getName());
  72
  73     // ------------------------------------------------------------------------
  74     // Variables --------------------------------------------------------------
  75     // ------------------------------------------------------------------------
  76
  77     /**
  78      * The emulator.
  79      */
  80     private ECMA48 emulator;
  81
  82     /**
  83      * The Process created by the shell spawning constructor.
  84      */
  85     private Process shell;
  86
  87     /**
  88      * If true, we are using the ptypipe utility to support dynamic window
  89      * resizing.  ptypipe is available at
  90      * https://gitlab.com/klamonte/ptypipe .
  91      */
  92     private boolean ptypipe = false;
  93
  94     /**
  95      * Double-height font.
  96      */
  97     private GlyphMaker doubleFont;
  98
  99     /**
 100      * Last text width value.
 101      */
 102     private int lastTextWidth = -1;
 103
 104     /**
 105      * Last text height value.
 106      */
 107     private int lastTextHeight = -1;
 108
 109     /**
 110      * The blink state, used only by ECMA48 backend and when double-width
 111      * chars must be drawn.
 112      */
 113     private boolean blinkState = true;
 114
 115     /**
 116      * Timer flag, used only by ECMA48 backend and when double-width chars
 117      * must be drawn.
 118      */
 119     private boolean haveTimer = false;
 120
 121     /**
 122      * The last seen visible display.
 123      */
 124     private List<DisplayLine> display;
 125
 126     /**
 127      * If true, the display has changed and needs updating.
 128      */
 129     private volatile boolean dirty = true;
 130
 131     /**
 132      * Time that the display was last updated.
 133      */
 134     private long lastUpdateTime = 0;
 135
 136     /**
 137      * If true, hide the mouse after typing a keystroke.
 138      */
 139     private boolean hideMouseWhenTyping = true;
 140
 141     /**
 142      * If true, the mouse should not be displayed because a keystroke was
 143      * typed.
 144      */
 145     private boolean typingHidMouse = false;
 146
 147     /**
 148      * The return value from the emulator.
 149      */
 150     private int exitValue = -1;
 151
 152     /**
 153      * Title to expose to a window.
 154      */
 155     private String title = "";
 156
 157     /**
 158      * Action to perform when the terminal exits.
 159      */
 160     private TAction closeAction = null;
 161
 162     // ------------------------------------------------------------------------
 163     // Constructors -----------------------------------------------------------
 164     // ------------------------------------------------------------------------
 165
 166     /**
 167      * Public constructor spawns a custom command line.
 168      *
 169      * @param parent parent widget
 170      * @param x column relative to parent
 171      * @param y row relative to parent
 172      * @param commandLine the command line to execute
 173      */
 174     public TTerminalWidget(final TWidget parent, final int x, final int y,
 175         final String commandLine) {
 176
 177         this(parent, x, y, commandLine.split("\\s+"));
 178     }
 179
 180     /**
 181      * Public constructor spawns a custom command line.
 182      *
 183      * @param parent parent widget
 184      * @param x column relative to parent
 185      * @param y row relative to parent
 186      * @param command the command line to execute
 187      */
 188     public TTerminalWidget(final TWidget parent, final int x, final int y,
 189         final String [] command) {
 190
 191         this(parent, x, y, command, null);
 192     }
 193
 194     /**
 195      * Public constructor spawns a custom command line.
 196      *
 197      * @param parent parent widget
 198      * @param x column relative to parent
 199      * @param y row relative to parent
 200      * @param command the command line to execute
 201      * @param closeAction action to perform when the shell sxits
 202      */
 203     public TTerminalWidget(final TWidget parent, final int x, final int y,
 204         final String [] command, final TAction closeAction) {
 205
 206         this(parent, x, y, 80, 24, command, closeAction);
 207     }
 208
 209     /**
 210      * Public constructor spawns a custom command line.
 211      *
 212      * @param parent parent widget
 213      * @param x column relative to parent
 214      * @param y row relative to parent
 215      * @param width width of widget
 216      * @param height height of widget
 217      * @param command the command line to execute
 218      * @param closeAction action to perform when the shell sxits
 219      */
 220     public TTerminalWidget(final TWidget parent, final int x, final int y,
 221         final int width, final int height, final String [] command,
 222         final TAction closeAction) {
 223
 224         super(parent, x, y, width, height);
 225
 226         this.closeAction = closeAction;
 227
 228         String [] fullCommand;
 229
 230         // Spawn a shell and pass its I/O to the other constructor.
 231         if ((System.getProperty("jexer.TTerminal.ptypipe") != null)
 232             && (System.getProperty("jexer.TTerminal.ptypipe").
 233                 equals("true"))
 234         ) {
 235             ptypipe = true;
 236             fullCommand = new String[command.length + 1];
 237             fullCommand[0] = "ptypipe";
 238             System.arraycopy(command, 0, fullCommand, 1, command.length);
 239         } else if (System.getProperty("os.name").startsWith("Windows")) {
 240             fullCommand = new String[3];
 241             fullCommand[0] = "cmd";
 242             fullCommand[1] = "/c";
 243             fullCommand[2] = stringArrayToString(command);
 244         } else if (System.getProperty("os.name").startsWith("Mac")) {
 245             fullCommand = new String[6];
 246             fullCommand[0] = "script";
 247             fullCommand[1] = "-q";
 248             fullCommand[2] = "-F";
 249             fullCommand[3] = "/dev/null";
 250             fullCommand[4] = "-c";
 251             fullCommand[5] = stringArrayToString(command);
 252         } else {
 253             // Default: behave like Linux
 254             fullCommand = new String[5];
 255             fullCommand[0] = "script";
 256             fullCommand[1] = "-fqe";
 257             fullCommand[2] = "/dev/null";
 258             fullCommand[3] = "-c";
 259             fullCommand[4] = stringArrayToString(command);
 260         }
 261         spawnShell(fullCommand);
 262     }
 263
 264     /**
 265      * Public constructor spawns a shell.
 266      *
 267      * @param parent parent widget
 268      * @param x column relative to parent
 269      * @param y row relative to parent
 270      */
 271     public TTerminalWidget(final TWidget parent, final int x, final int y) {
 272         this(parent, x, y, (TAction) null);
 273     }
 274
 275     /**
 276      * Public constructor spawns a shell.
 277      *
 278      * @param parent parent widget
 279      * @param x column relative to parent
 280      * @param y row relative to parent
 281      * @param closeAction action to perform when the shell sxits
 282      */
 283     public TTerminalWidget(final TWidget parent, final int x, final int y,
 284         final TAction closeAction) {
 285
 286         this(parent, x, y, 80, 24, closeAction);
 287     }
 288
 289     /**
 290      * Public constructor spawns a shell.
 291      *
 292      * @param parent parent widget
 293      * @param x column relative to parent
 294      * @param y row relative to parent
 295      * @param width width of widget
 296      * @param height height of widget
 297      * @param closeAction action to perform when the shell sxits
 298      */
 299     public TTerminalWidget(final TWidget parent, final int x, final int y,
 300         final int width, final int height, final TAction closeAction) {
 301
 302         super(parent, x, y, width, height);
 303
 304         this.closeAction = closeAction;
 305
 306         if (System.getProperty("jexer.TTerminal.shell") != null) {
 307             String shell = System.getProperty("jexer.TTerminal.shell");
 308             if (shell.trim().startsWith("ptypipe")) {
 309                 ptypipe = true;
 310             }
 311             spawnShell(shell.split("\\s+"));
 312             return;
 313         }
 314
 315         String cmdShellWindows = "cmd.exe";
 316
 317         // You cannot run a login shell in a bare Process interactively, due
 318         // to libc's behavior of buffering when stdin/stdout aren't a tty.
 319         // Use 'script' instead to run a shell in a pty.  And because BSD and
 320         // GNU differ on the '-f' vs '-F' flags, we need two different
 321         // commands.  Lovely.
 322         String cmdShellGNU = "script -fqe /dev/null";
 323         String cmdShellBSD = "script -q -F /dev/null";
 324
 325         // ptypipe is another solution that permits dynamic window resizing.
 326         String cmdShellPtypipe = "ptypipe /bin/bash --login";
 327
 328         // Spawn a shell and pass its I/O to the other constructor.
 329         if ((System.getProperty("jexer.TTerminal.ptypipe") != null)
 330             && (System.getProperty("jexer.TTerminal.ptypipe").
 331                 equals("true"))
 332         ) {
 333             ptypipe = true;
 334             spawnShell(cmdShellPtypipe.split("\\s+"));
 335         } else if (System.getProperty("os.name").startsWith("Windows")) {
 336             spawnShell(cmdShellWindows.split("\\s+"));
 337         } else if (System.getProperty("os.name").startsWith("Mac")) {
 338             spawnShell(cmdShellBSD.split("\\s+"));
 339         } else if (System.getProperty("os.name").startsWith("Linux")) {
 340             spawnShell(cmdShellGNU.split("\\s+"));
 341         } else {
 342             // When all else fails, assume GNU.
 343             spawnShell(cmdShellGNU.split("\\s+"));
 344         }
 345     }
 346
 347     // ------------------------------------------------------------------------
 348     // Event handlers ---------------------------------------------------------
 349     // ------------------------------------------------------------------------
 350
 351     /**
 352      * Handle window/screen resize events.
 353      *
 354      * @param resize resize event
 355      */
 356     @Override
 357     public void onResize(final TResizeEvent resize) {
 358         // Let TWidget set my size.
 359         super.onResize(resize);
 360
 361         if (emulator == null) {
 362             return;
 363         }
 364
 365         // Synchronize against the emulator so we don't stomp on its reader
 366         // thread.
 367         synchronized (emulator) {
 368
 369             if (resize.getType() == TResizeEvent.Type.WIDGET) {
 370                 // Resize the scroll bars
 371                 reflowData();
 372                 placeScrollbars();
 373
 374                 // Get out of scrollback
 375                 setVerticalValue(0);
 376
 377                 if (ptypipe) {
 378                     emulator.setWidth(getWidth());
 379                     emulator.setHeight(getHeight());
 380
 381                     emulator.writeRemote("\033[8;" + getHeight() + ";" +
 382                         getWidth() + "t");
 383                 }
 384
 385                 // Pass the correct text cell width/height to the emulator
 386                 if (getScreen() != null) {
 387                     emulator.setTextWidth(getScreen().getTextWidth());
 388                     emulator.setTextHeight(getScreen().getTextHeight());
 389                 }
 390             }
 391             return;
 392
 393         } // synchronized (emulator)
 394     }
 395
 396     /**
 397      * Handle keystrokes.
 398      *
 399      * @param keypress keystroke event
 400      */
 401     @Override
 402     public void onKeypress(final TKeypressEvent keypress) {
 403         if (hideMouseWhenTyping) {
 404             typingHidMouse = true;
 405         }
 406
 407         // Scrollback up/down
 408         if (keypress.equals(kbShiftPgUp)
 409             || keypress.equals(kbCtrlPgUp)
 410             || keypress.equals(kbAltPgUp)
 411         ) {
 412             bigVerticalDecrement();
 413             dirty = true;
 414             return;
 415         }
 416         if (keypress.equals(kbShiftPgDn)
 417             || keypress.equals(kbCtrlPgDn)
 418             || keypress.equals(kbAltPgDn)
 419         ) {
 420             bigVerticalIncrement();
 421             dirty = true;
 422             return;
 423         }
 424
 425         if ((emulator != null) && (emulator.isReading())) {
 426             // Get out of scrollback
 427             setVerticalValue(0);
 428             emulator.addUserEvent(keypress);
 429
 430             // UGLY HACK TIME!  cmd.exe needs CRLF, not just CR, so if
 431             // this is kBEnter then also send kbCtrlJ.
 432             if (keypress.equals(kbEnter)) {
 433                 if (System.getProperty("os.name").startsWith("Windows")
 434                     && (System.getProperty("jexer.TTerminal.cmdHack",
 435                             "true").equals("true"))
 436                 ) {
 437                     emulator.addUserEvent(new TKeypressEvent(kbCtrlJ));
 438                 }
 439             }
 440
 441             readEmulatorState();
 442             return;
 443         }
 444
 445         // Process is closed, honor "normal" TUI keystrokes
 446         super.onKeypress(keypress);
 447     }
 448
 449     /**
 450      * Handle mouse press events.
 451      *
 452      * @param mouse mouse button press event
 453      */
 454     @Override
 455     public void onMouseDown(final TMouseEvent mouse) {
 456         if (hideMouseWhenTyping) {
 457             typingHidMouse = false;
 458         }
 459
 460         if (emulator != null) {
 461             // If the emulator is tracking mouse buttons, it needs to see
 462             // wheel events.
 463             if (emulator.getMouseProtocol() == ECMA48.MouseProtocol.OFF) {
 464                 if (mouse.isMouseWheelUp()) {
 465                     verticalDecrement();
 466                     dirty = true;
 467                     return;
 468                 }
 469                 if (mouse.isMouseWheelDown()) {
 470                     verticalIncrement();
 471                     dirty = true;
 472                     return;
 473                 }
 474             }
 475             if (mouseOnEmulator(mouse)) {
 476                 emulator.addUserEvent(mouse);
 477                 readEmulatorState();
 478                 return;
 479             }
 480         }
 481
 482         // Emulator didn't consume it, pass it on
 483         super.onMouseDown(mouse);
 484     }
 485
 486     /**
 487      * Handle mouse release events.
 488      *
 489      * @param mouse mouse button release event
 490      */
 491     @Override
 492     public void onMouseUp(final TMouseEvent mouse) {
 493         if (hideMouseWhenTyping) {
 494             typingHidMouse = false;
 495         }
 496
 497         if ((emulator != null) && (mouseOnEmulator(mouse))) {
 498             emulator.addUserEvent(mouse);
 499             readEmulatorState();
 500             return;
 501         }
 502
 503         // Emulator didn't consume it, pass it on
 504         super.onMouseUp(mouse);
 505     }
 506
 507     /**
 508      * Handle mouse motion events.
 509      *
 510      * @param mouse mouse motion event
 511      */
 512     @Override
 513     public void onMouseMotion(final TMouseEvent mouse) {
 514         if (hideMouseWhenTyping) {
 515             typingHidMouse = false;
 516         }
 517
 518         if ((emulator != null) && (mouseOnEmulator(mouse))) {
 519             emulator.addUserEvent(mouse);
 520             readEmulatorState();
 521             return;
 522         }
 523
 524         // Emulator didn't consume it, pass it on
 525         super.onMouseMotion(mouse);
 526     }
 527
 528     // ------------------------------------------------------------------------
 529     // TScrollableWidget ------------------------------------------------------
 530     // ------------------------------------------------------------------------
 531
 532     /**
 533      * Draw the display buffer.
 534      */
 535     @Override
 536     public void draw() {
 537         if (emulator == null) {
 538             return;
 539         }
 540
 541         int width = getDisplayWidth();
 542
 543         boolean syncEmulator = false;
 544         if ((System.currentTimeMillis() - lastUpdateTime >= 20)
 545             && (dirty == true)
 546         ) {
 547             // Too much time has passed, draw it all.
 548             syncEmulator = true;
 549         } else if (emulator.isReading() && (dirty == false)) {
 550             // Wait until the emulator has brought more data in.
 551             syncEmulator = false;
 552         } else if (!emulator.isReading() && (dirty == true)) {
 553             // The emulator won't receive more data, update the display.
 554             syncEmulator = true;
 555         }
 556
 557         if ((syncEmulator == true)
 558             || (display == null)
 559         ) {
 560             // We want to minimize the amount of time we have the emulator
 561             // locked.  Grab a copy of its display.
 562             synchronized (emulator) {
 563                 // Update the scroll bars
 564                 reflowData();
 565
 566                 if (!isDrawable()) {
 567                     // We lost the connection, onShellExit() called an action
 568                     // that ultimately removed this widget from the UI
 569                     // hierarchy, so no one cares if we update the display.
 570                     // Bail out.
 571                     return;
 572                 }
 573
 574                 if ((display == null) || emulator.isReading()) {
 575                     display = emulator.getVisibleDisplay(getHeight(),
 576                         -getVerticalValue());
 577                     assert (display.size() == getHeight());
 578                 }
 579                 width = emulator.getWidth();
 580             }
 581             dirty = false;
 582         }
 583
 584         // Now draw the emulator screen
 585         int row = 0;
 586         for (DisplayLine line: display) {
 587             int widthMax = width;
 588             if (line.isDoubleWidth()) {
 589                 widthMax /= 2;
 590             }
 591             if (widthMax > getWidth()) {
 592                 widthMax = getWidth();
 593             }
 594             for (int i = 0; i < widthMax; i++) {
 595                 Cell ch = line.charAt(i);
 596
 597                 if (ch.isImage()) {
 598                     putCharXY(i, row, ch);
 599                     continue;
 600                 }
 601
 602                 Cell newCell = new Cell(ch);
 603                 boolean reverse = line.isReverseColor() ^ ch.isReverse();
 604                 newCell.setReverse(false);
 605                 if (reverse) {
 606                     if (ch.getForeColorRGB() < 0) {
 607                         newCell.setBackColor(ch.getForeColor());
 608                         newCell.setBackColorRGB(-1);
 609                     } else {
 610                         newCell.setBackColorRGB(ch.getForeColorRGB());
 611                     }
 612                     if (ch.getBackColorRGB() < 0) {
 613                         newCell.setForeColor(ch.getBackColor());
 614                         newCell.setForeColorRGB(-1);
 615                     } else {
 616                         newCell.setForeColorRGB(ch.getBackColorRGB());
 617                     }
 618                 }
 619                 if (line.isDoubleWidth()) {
 620                     putDoubleWidthCharXY(line, (i * 2), row, newCell);
 621                 } else {
 622                     putCharXY(i, row, newCell);
 623                 }
 624             }
 625             row++;
 626         }
 627     }
 628
 629     /**
 630      * Set current value of the vertical scroll.
 631      *
 632      * @param value the new scroll value
 633      */
 634     @Override
 635     public void setVerticalValue(final int value) {
 636         super.setVerticalValue(value);
 637         dirty = true;
 638     }
 639
 640     /**
 641      * Perform a small step change up.
 642      */
 643     @Override
 644     public void verticalDecrement() {
 645         super.verticalDecrement();
 646         dirty = true;
 647     }
 648
 649     /**
 650      * Perform a small step change down.
 651      */
 652     @Override
 653     public void verticalIncrement() {
 654         super.verticalIncrement();
 655         dirty = true;
 656     }
 657
 658     /**
 659      * Perform a big step change up.
 660      */
 661     public void bigVerticalDecrement() {
 662         super.bigVerticalDecrement();
 663         dirty = true;
 664     }
 665
 666     /**
 667      * Perform a big step change down.
 668      */
 669     public void bigVerticalIncrement() {
 670         super.bigVerticalIncrement();
 671         dirty = true;
 672     }
 673
 674     /**
 675      * Go to the top edge of the vertical scroller.
 676      */
 677     public void toTop() {
 678         super.toTop();
 679         dirty = true;
 680     }
 681
 682     /**
 683      * Go to the bottom edge of the vertical scroller.
 684      */
 685     public void toBottom() {
 686         super.toBottom();
 687         dirty = true;
 688     }
 689
 690     /**
 691      * Handle widget close.
 692      */
 693     @Override
 694     public void close() {
 695         if (emulator != null) {
 696             emulator.close();
 697         }
 698         if (shell != null) {
 699             terminateShellChildProcess();
 700             shell.destroy();
 701             shell = null;
 702         }
 703     }
 704
 705     /**
 706      * Resize scrollbars for a new width/height.
 707      */
 708     @Override
 709     public void reflowData() {
 710         if (emulator == null) {
 711             return;
 712         }
 713
 714         // Synchronize against the emulator so we don't stomp on its reader
 715         // thread.
 716         synchronized (emulator) {
 717
 718             // Pull cursor information
 719             readEmulatorState();
 720
 721             // Vertical scrollbar
 722             setTopValue(getHeight()
 723                 - (emulator.getScrollbackBuffer().size()
 724                     + emulator.getDisplayBuffer().size()));
 725             setVerticalBigChange(getHeight());
 726
 727         } // synchronized (emulator)
 728     }
 729
 730     // ------------------------------------------------------------------------
 731     // TTerminalWidget --------------------------------------------------------
 732     // ------------------------------------------------------------------------
 733
 734     /**
 735      * Get the desired window title.
 736      *
 737      * @return the title
 738      */
 739     public String getTitle() {
 740         return title;
 741     }
 742
 743     /**
 744      * Returns true if this widget does not want the application-wide mouse
 745      * cursor drawn over it.
 746      *
 747      * @return true if this widget does not want the application-wide mouse
 748      * cursor drawn over it
 749      */
 750     public boolean hasHiddenMouse() {
 751         if (emulator == null) {
 752             return false;
 753         }
 754         return (emulator.hasHiddenMousePointer() || typingHidMouse);
 755     }
 756
 757     /**
 758      * See if the terminal is still running.
 759      *
 760      * @return if true, we are still connected to / reading from the remote
 761      * side
 762      */
 763     public boolean isReading() {
 764         if (emulator == null) {
 765             return false;
 766         }
 767         return emulator.isReading();
 768     }
 769
 770     /**
 771      * Convert a string array to a whitespace-separated string.
 772      *
 773      * @param array the string array
 774      * @return a single string
 775      */
 776     private String stringArrayToString(final String [] array) {
 777         StringBuilder sb = new StringBuilder(array[0].length());
 778         for (int i = 0; i < array.length; i++) {
 779             sb.append(array[i]);
 780             if (i < array.length - 1) {
 781                 sb.append(' ');
 782             }
 783         }
 784         return sb.toString();
 785     }
 786
 787     /**
 788      * Spawn the shell.
 789      *
 790      * @param command the command line to execute
 791      */
 792     private void spawnShell(final String [] command) {
 793
 794         /*
 795         System.err.printf("spawnShell(): '%s'\n",
 796             stringArrayToString(command));
 797         */
 798
 799         // We will have vScroller for its data fields and mouse event
 800         // handling, but do not want to draw it.
 801         vScroller = new TVScroller(null, getWidth(), 0, getHeight());
 802         vScroller.setVisible(false);
 803         setBottomValue(0);
 804
 805         title = i18n.getString("windowTitle");
 806
 807         // Assume XTERM
 808         ECMA48.DeviceType deviceType = ECMA48.DeviceType.XTERM;
 809
 810         try {
 811             ProcessBuilder pb = new ProcessBuilder(command);
 812             Map<String, String> env = pb.environment();
 813             env.put("TERM", ECMA48.deviceTypeTerm(deviceType));
 814             env.put("LANG", ECMA48.deviceTypeLang(deviceType, "en"));
 815             env.put("COLUMNS", "80");
 816             env.put("LINES", "24");
 817             pb.redirectErrorStream(true);
 818             shell = pb.start();
 819             emulator = new ECMA48(deviceType, shell.getInputStream(),
 820                 shell.getOutputStream(), this);
 821         } catch (IOException e) {
 822             messageBox(i18n.getString("errorLaunchingShellTitle"),
 823                 MessageFormat.format(i18n.getString("errorLaunchingShellText"),
 824                     e.getMessage()));
 825         }
 826
 827         // Setup the scroll bars
 828         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 829                 getHeight()));
 830
 831         // Hide mouse when typing option
 832         if (System.getProperty("jexer.TTerminal.hideMouseWhenTyping",
 833                 "true").equals("false")) {
 834
 835             hideMouseWhenTyping = false;
 836         }
 837     }
 838
 839     /**
 840      * Terminate the child of the 'script' process used on POSIX.  This may
 841      * or may not work.
 842      */
 843     private void terminateShellChildProcess() {
 844         int pid = -1;
 845         if (shell.getClass().getName().equals("java.lang.UNIXProcess")) {
 846             /* get the PID on unix/linux systems */
 847             try {
 848                 Field field = shell.getClass().getDeclaredField("pid");
 849                 field.setAccessible(true);
 850                 pid = field.getInt(shell);
 851             } catch (Throwable e) {
 852                 // SQUASH, this didn't work.  Just bail out quietly.
 853                 return;
 854             }
 855         }
 856         if (pid != -1) {
 857             // shell.destroy() works successfully at killing this side of
 858             // 'script'.  But we need to make sure the other side (child
 859             // process) is also killed.
 860             String [] cmdKillIt = {
 861                 "pkill", "-P", Integer.toString(pid)
 862             };
 863             try {
 864                 Runtime.getRuntime().exec(cmdKillIt);
 865             } catch (Throwable e) {
 866                 // SQUASH, this didn't work.  Just bail out quietly.
 867                 return;
 868             }
 869         }
 870     }
 871
 872     /**
 873      * Hook for subclasses to be notified of the shell termination.
 874      */
 875     public void onShellExit() {
 876         TApplication app = getApplication();
 877         if (app != null) {
 878             if (closeAction != null) {
 879                 // We have to put this action inside invokeLater() because it
 880                 // could be executed during draw() when syncing with ECMA48.
 881                 app.invokeLater(new Runnable() {
 882                     public void run() {
 883                         closeAction.DO(TTerminalWidget.this);
 884                     }
 885                 });
 886             }
 887             if (getApplication() != null) {
 888                 getApplication().postEvent(new TMenuEvent(
 889                     TMenu.MID_REPAINT));
 890             }
 891         }
 892     }
 893
 894     /**
 895      * Copy out variables from the emulator that TTerminal has to expose on
 896      * screen.
 897      */
 898     private void readEmulatorState() {
 899         if (emulator == null) {
 900             return;
 901         }
 902
 903         // Synchronize against the emulator so we don't stomp on its reader
 904         // thread.
 905         synchronized (emulator) {
 906
 907             setCursorX(emulator.getCursorX());
 908             setCursorY(emulator.getCursorY()
 909                 + (getHeight() - emulator.getHeight())
 910                 - getVerticalValue());
 911             setCursorVisible(emulator.isCursorVisible());
 912             if (getCursorX() > getWidth()) {
 913                 setCursorVisible(false);
 914             }
 915             if ((getCursorY() >= getHeight()) || (getCursorY() < 0)) {
 916                 setCursorVisible(false);
 917             }
 918             if (emulator.getScreenTitle().length() > 0) {
 919                 // Only update the title if the shell is still alive
 920                 if (shell != null) {
 921                     title = emulator.getScreenTitle();
 922                 }
 923             }
 924
 925             // Check to see if the shell has died.
 926             if (!emulator.isReading() && (shell != null)) {
 927                 try {
 928                     int rc = shell.exitValue();
 929                     // The emulator exited on its own, all is fine
 930                     title = MessageFormat.format(i18n.
 931                         getString("windowTitleCompleted"), title, rc);
 932                     exitValue = rc;
 933                     shell = null;
 934                     emulator.close();
 935                     onShellExit();
 936                 } catch (IllegalThreadStateException e) {
 937                     // The emulator thread has exited, but the shell Process
 938                     // hasn't figured that out yet.  Do nothing, we will see
 939                     // this in a future tick.
 940                 }
 941             } else if (emulator.isReading() && (shell != null)) {
 942                 // The shell might be dead, let's check
 943                 try {
 944                     int rc = shell.exitValue();
 945                     // If we got here, the shell died.
 946                     title = MessageFormat.format(i18n.
 947                         getString("windowTitleCompleted"), title, rc);
 948                     exitValue = rc;
 949                     shell = null;
 950                     emulator.close();
 951                     onShellExit();
 952                 } catch (IllegalThreadStateException e) {
 953                     // The shell is still running, do nothing.
 954                 }
 955             }
 956
 957         } // synchronized (emulator)
 958     }
 959
 960     /**
 961      * Check if a mouse press/release/motion event coordinate is over the
 962      * emulator.
 963      *
 964      * @param mouse a mouse-based event
 965      * @return whether or not the mouse is on the emulator
 966      */
 967     private boolean mouseOnEmulator(final TMouseEvent mouse) {
 968         if (emulator == null) {
 969             return false;
 970         }
 971
 972         if (!emulator.isReading()) {
 973             return false;
 974         }
 975
 976         if ((mouse.getX() >= 0)
 977             && (mouse.getX() < getWidth() - 1)
 978             && (mouse.getY() >= 0)
 979             && (mouse.getY() < getHeight())
 980         ) {
 981             return true;
 982         }
 983         return false;
 984     }
 985
 986     /**
 987      * Draw glyphs for a double-width or double-height VT100 cell to two
 988      * screen cells.
 989      *
 990      * @param line the line this VT100 cell is in
 991      * @param x the X position to draw the left half to
 992      * @param y the Y position to draw to
 993      * @param cell the cell to draw
 994      */
 995     private void putDoubleWidthCharXY(final DisplayLine line, final int x,
 996         final int y, final Cell cell) {
 997
 998         int textWidth = getScreen().getTextWidth();
 999         int textHeight = getScreen().getTextHeight();
1000         boolean cursorBlinkVisible = true;
1001
1002         if (getScreen() instanceof SwingTerminal) {
1003             SwingTerminal terminal = (SwingTerminal) getScreen();
1004             cursorBlinkVisible = terminal.getCursorBlinkVisible();
1005         } else if (getScreen() instanceof ECMA48Terminal) {
1006             ECMA48Terminal terminal = (ECMA48Terminal) getScreen();
1007
1008             if (!terminal.hasSixel()) {
1009                 // The backend does not have sixel support, draw this as text
1010                 // and bail out.
1011                 putCharXY(x, y, cell);
1012                 putCharXY(x + 1, y, ' ', cell);
1013                 return;
1014             }
1015             cursorBlinkVisible = blinkState;
1016         } else {
1017             // We don't know how to dray glyphs to this screen, draw them as
1018             // text and bail out.
1019             putCharXY(x, y, cell);
1020             putCharXY(x + 1, y, ' ', cell);
1021             return;
1022         }
1023
1024         if ((textWidth != lastTextWidth) || (textHeight != lastTextHeight)) {
1025             // Screen size has changed, reset the font.
1026             setupFont(textHeight);
1027             lastTextWidth = textWidth;
1028             lastTextHeight = textHeight;
1029         }
1030         assert (doubleFont != null);
1031
1032         BufferedImage image;
1033         if (line.getDoubleHeight() == 1) {
1034             // Double-height top half: don't draw the underline.
1035             Cell newCell = new Cell(cell);
1036             newCell.setUnderline(false);
1037             image = doubleFont.getImage(newCell, textWidth * 2, textHeight * 2,
1038                 cursorBlinkVisible);
1039         } else {
1040             image = doubleFont.getImage(cell,  textWidth * 2, textHeight * 2,
1041                 cursorBlinkVisible);
1042         }
1043
1044         // Now that we have the double-wide glyph drawn, copy the right
1045         // pieces of it to the cells.
1046         Cell left = new Cell(cell);
1047         Cell right = new Cell(cell);
1048         right.setChar(' ');
1049         BufferedImage leftImage = null;
1050         BufferedImage rightImage = null;
1051         /*
1052         System.err.println("image " + image + " textWidth " + textWidth +
1053             " textHeight " + textHeight);
1054          */
1055
1056         switch (line.getDoubleHeight()) {
1057         case 1:
1058             // Top half double height
1059             leftImage = image.getSubimage(0, 0, textWidth, textHeight);
1060             rightImage = image.getSubimage(textWidth, 0, textWidth, textHeight);
1061             break;
1062         case 2:
1063             // Bottom half double height
1064             leftImage = image.getSubimage(0, textHeight, textWidth, textHeight);
1065             rightImage = image.getSubimage(textWidth, textHeight,
1066                 textWidth, textHeight);
1067             break;
1068         default:
1069             // Either single height double-width, or error fallback
1070             BufferedImage wideImage = new BufferedImage(textWidth * 2,
1071                 textHeight, BufferedImage.TYPE_INT_ARGB);
1072             Graphics2D grWide = wideImage.createGraphics();
1073             grWide.drawImage(image, 0, 0, wideImage.getWidth(),
1074                 wideImage.getHeight(), null);
1075             grWide.dispose();
1076             leftImage = wideImage.getSubimage(0, 0, textWidth, textHeight);
1077             rightImage = wideImage.getSubimage(textWidth, 0, textWidth,
1078                 textHeight);
1079             break;
1080         }
1081         left.setImage(leftImage);
1082         right.setImage(rightImage);
1083         // Since we have image data, ditch the character here.  Otherwise, a
1084         // drawBoxShadow() over the terminal window will show the characters
1085         // which looks wrong.
1086         left.setChar(' ');
1087         right.setChar(' ');
1088         putCharXY(x, y, left);
1089         putCharXY(x + 1, y, right);
1090     }
1091
1092     /**
1093      * Set up the double-width font.
1094      *
1095      * @param fontSize the size of font to request for the single-width font.
1096      * The double-width font will be 2x this value.
1097      */
1098     private void setupFont(final int fontSize) {
1099         doubleFont = GlyphMaker.getInstance(fontSize * 2);
1100
1101         // Special case: the ECMA48 backend needs to have a timer to drive
1102         // its blink state.
1103         if (getScreen() instanceof jexer.backend.ECMA48Terminal) {
1104             if (!haveTimer) {
1105                 // Blink every 500 millis.
1106                 long millis = 500;
1107                 getApplication().addTimer(millis, true,
1108                     new TAction() {
1109                         public void DO() {
1110                             blinkState = !blinkState;
1111                             getApplication().doRepaint();
1112                         }
1113                     }
1114                 );
1115                 haveTimer = true;
1116             }
1117         }
1118     }
1119
1120     // ------------------------------------------------------------------------
1121     // DisplayListener --------------------------------------------------------
1122     // ------------------------------------------------------------------------
1123
1124     /**
1125      * Called by emulator when fresh data has come in.
1126      */
1127     public void displayChanged() {
1128         dirty = true;
1129         getApplication().postEvent(new TMenuEvent(TMenu.MID_REPAINT));
1130     }
1131
1132     /**
1133      * Function to call to obtain the display width.
1134      *
1135      * @return the number of columns in the display
1136      */
1137     public int getDisplayWidth() {
1138         if (ptypipe) {
1139             return getWidth();
1140         }
1141         return 80;
1142     }
1143
1144     /**
1145      * Function to call to obtain the display height.
1146      *
1147      * @return the number of rows in the display
1148      */
1149     public int getDisplayHeight() {
1150         if (ptypipe) {
1151             return getHeight();
1152         }
1153         return 24;
1154     }
1155
1156 }