src/main/resources/keyboard.js

   1
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is guacamole-common-js.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Michael Jumper.
  19  * Portions created by the Initial Developer are Copyright (C) 2010
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either the GNU General Public License Version 2 or later (the "GPL"), or
  26  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
  30  * use your version of this file under the terms of the MPL, indicate your
  31  * decision by deleting the provisions above and replace them with the notice
  32  * and other provisions required by the GPL or the LGPL. If you do not delete
  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 // Guacamole namespace
  39 var Guacamole = Guacamole || {};
  40
  41 /**
  42  * Provides cross-browser and cross-keyboard keyboard for a specific element.
  43  * Browser and keyboard layout variation is abstracted away, providing events
  44  * which represent keys as their corresponding X11 keysym.
  45  *
  46  * @constructor
  47  * @param {Element} element The Element to use to provide keyboard events.
  48  */
  49 Guacamole.Keyboard = function(element) {
  50
  51     /**
  52      * Reference to this Guacamole.Keyboard.
  53      * @private
  54      */
  55     var guac_keyboard = this;
  56
  57     /**
  58      * Fired whenever the user presses a key with the element associated
  59      * with this Guacamole.Keyboard in focus.
  60      *
  61      * @event
  62      * @param {Number} keysym The keysym of the key being pressed.
  63      * @returns {Boolean} true if the originating event of this keypress should
  64      *                    be allowed through to the browser, false or undefined
  65      *                    otherwise.
  66      */
  67     this.onkeydown = null;
  68
  69     /**
  70      * Fired whenever the user releases a key with the element associated
  71      * with this Guacamole.Keyboard in focus.
  72      *
  73      * @event
  74      * @param {Number} keysym The keysym of the key being released.
  75      * @returns {Boolean} true if the originating event of this key release
  76      *                    should be allowed through to the browser, false or
  77      *                    undefined otherwise.
  78      */
  79     this.onkeyup = null;
  80
  81     /**
  82      * Map of known JavaScript keycodes which do not map to typable characters
  83      * to their unshifted X11 keysym equivalents.
  84      * @private
  85      */
  86     var unshiftedKeySym = {
  87         8:   0xFF08, // backspace
  88         9:   0xFF09, // tab
  89         13:  0xFF0D, // enter
  90         16:  0xFFE1, // shift
  91         17:  0xFFE3, // ctrl
  92         18:  0xFFE9, // alt
  93         19:  0xFF13, // pause/break
  94         20:  0xFFE5, // caps lock
  95         27:  0xFF1B, // escape
  96         32:  0x0020, // space
  97         33:  0xFF55, // page up
  98         34:  0xFF56, // page down
  99         35:  0xFF57, // end
 100         36:  0xFF50, // home
 101         37:  0xFF51, // left arrow
 102         38:  0xFF52, // up arrow
 103         39:  0xFF53, // right arrow
 104         40:  0xFF54, // down arrow
 105         45:  0xFF63, // insert
 106         46:  0xFFFF, // delete
 107         91:  0xFFEB, // left window key (super_l)
 108         92:  0xFF67, // right window key (menu key?)
 109         93:  null,   // select key
 110         112: 0xFFBE, // f1
 111         113: 0xFFBF, // f2
 112         114: 0xFFC0, // f3
 113         115: 0xFFC1, // f4
 114         116: 0xFFC2, // f5
 115         117: 0xFFC3, // f6
 116         118: 0xFFC4, // f7
 117         119: 0xFFC5, // f8
 118         120: 0xFFC6, // f9
 119         121: 0xFFC7, // f10
 120         122: 0xFFC8, // f11
 121         123: 0xFFC9, // f12
 122         144: 0xFF7F, // num lock
 123         145: 0xFF14  // scroll lock
 124     };
 125
 126     /**
 127      * Map of known JavaScript keyidentifiers which do not map to typable
 128      * characters to their unshifted X11 keysym equivalents.
 129      * @private
 130      */
 131     var keyidentifier_keysym = {
 132         "AllCandidates": 0xFF3D,
 133         "Alphanumeric": 0xFF30,
 134         "Alt": 0xFFE9,
 135         "Attn": 0xFD0E,
 136         "AltGraph": 0xFFEA,
 137         "CapsLock": 0xFFE5,
 138         "Clear": 0xFF0B,
 139         "Convert": 0xFF21,
 140         "Copy": 0xFD15,
 141         "Crsel": 0xFD1C,
 142         "CodeInput": 0xFF37,
 143         "Control": 0xFFE3,
 144         "Down": 0xFF54,
 145         "End": 0xFF57,
 146         "Enter": 0xFF0D,
 147         "EraseEof": 0xFD06,
 148         "Execute": 0xFF62,
 149         "Exsel": 0xFD1D,
 150         "F1": 0xFFBE,
 151         "F2": 0xFFBF,
 152         "F3": 0xFFC0,
 153         "F4": 0xFFC1,
 154         "F5": 0xFFC2,
 155         "F6": 0xFFC3,
 156         "F7": 0xFFC4,
 157         "F8": 0xFFC5,
 158         "F9": 0xFFC6,
 159         "F10": 0xFFC7,
 160         "F11": 0xFFC8,
 161         "F12": 0xFFC9,
 162         "F13": 0xFFCA,
 163         "F14": 0xFFCB,
 164         "F15": 0xFFCC,
 165         "F16": 0xFFCD,
 166         "F17": 0xFFCE,
 167         "F18": 0xFFCF,
 168         "F19": 0xFFD0,
 169         "F20": 0xFFD1,
 170         "F21": 0xFFD2,
 171         "F22": 0xFFD3,
 172         "F23": 0xFFD4,
 173         "F24": 0xFFD5,
 174         "Find": 0xFF68,
 175         "FullWidth": null,
 176         "HalfWidth": null,
 177         "HangulMode": 0xFF31,
 178         "HanjaMode": 0xFF34,
 179         "Help": 0xFF6A,
 180         "Hiragana": 0xFF25,
 181         "Home": 0xFF50,
 182         "Insert": 0xFF63,
 183         "JapaneseHiragana": 0xFF25,
 184         "JapaneseKatakana": 0xFF26,
 185         "JapaneseRomaji": 0xFF24,
 186         "JunjaMode": 0xFF38,
 187         "KanaMode": 0xFF2D,
 188         "KanjiMode": 0xFF21,
 189         "Katakana": 0xFF26,
 190         "Left": 0xFF51,
 191         "Meta": 0xFFE7,
 192         "NumLock": 0xFF7F,
 193         "PageDown": 0xFF55,
 194         "PageUp": 0xFF56,
 195         "Pause": 0xFF13,
 196         "PreviousCandidate": 0xFF3E,
 197         "PrintScreen": 0xFD1D,
 198         "Right": 0xFF53,
 199         "RomanCharacters": null,
 200         "Scroll": 0xFF14,
 201         "Select": 0xFF60,
 202         "Shift": 0xFFE1,
 203         "Up": 0xFF52,
 204         "Undo": 0xFF65,
 205         "Win": 0xFFEB
 206     };
 207
 208     /**
 209      * Map of known JavaScript keycodes which do not map to typable characters
 210      * to their shifted X11 keysym equivalents. Keycodes must only be listed
 211      * here if their shifted X11 keysym equivalents differ from their unshifted
 212      * equivalents.
 213      * @private
 214      */
 215     var shiftedKeySym = {
 216         18:  0xFFE7  // alt
 217     };
 218
 219     /**
 220      * All modifiers and their states.
 221      */
 222     this.modifiers = {
 223
 224         /**
 225          * Whether shift is currently pressed.
 226          */
 227         "shift": false,
 228
 229         /**
 230          * Whether ctrl is currently pressed.
 231          */
 232         "ctrl" : false,
 233
 234         /**
 235          * Whether alt is currently pressed.
 236          */
 237         "alt"  : false
 238
 239     };
 240
 241     /**
 242      * The state of every key, indexed by keysym. If a particular key is
 243      * pressed, the value of pressed for that keysym will be true. If a key
 244      * is not currently pressed, the value for that keysym may be false or
 245      * undefined.
 246      */
 247     this.pressed = [];
 248
 249     var keydownChar = new Array();
 250
 251     // ID of routine repeating keystrokes. -1 = not repeating.
 252     var repeatKeyTimeoutId = -1;
 253     var repeatKeyIntervalId = -1;
 254
 255     // Starts repeating keystrokes
 256     function startRepeat(keySym) {
 257         repeatKeyIntervalId = setInterval(function() {
 258             sendKeyReleased(keySym);
 259             sendKeyPressed(keySym);
 260         }, 50);
 261     }
 262
 263     // Stops repeating keystrokes
 264     function stopRepeat() {
 265         if (repeatKeyTimeoutId != -1) clearTimeout(repeatKeyTimeoutId);
 266         if (repeatKeyIntervalId != -1) clearInterval(repeatKeyIntervalId);
 267     }
 268
 269
 270     function getKeySymFromKeyIdentifier(shifted, keyIdentifier) {
 271
 272         var unicodePrefixLocation = keyIdentifier.indexOf("U+");
 273         if (unicodePrefixLocation >= 0) {
 274
 275             var hex = keyIdentifier.substring(unicodePrefixLocation+2);
 276             var codepoint = parseInt(hex, 16);
 277             var typedCharacter;
 278
 279             // Convert case if shifted
 280             if (shifted == 0)
 281                 typedCharacter = String.fromCharCode(codepoint).toLowerCase();
 282             else
 283                 typedCharacter = String.fromCharCode(codepoint).toUpperCase();
 284
 285             // Get codepoint
 286             codepoint = typedCharacter.charCodeAt(0);
 287
 288             return getKeySymFromCharCode(codepoint);
 289
 290         }
 291
 292         return keyidentifier_keysym[keyIdentifier];
 293
 294     }
 295
 296     function isControlCharacter(codepoint) {
 297         return codepoint <= 0x1F || (codepoint >= 0x7F && codepoint <= 0x9F);
 298     }
 299
 300     function getKeySymFromCharCode(codepoint) {
 301
 302         // Keysyms for control characters
 303         if (isControlCharacter(codepoint)) return 0xFF00 | codepoint;
 304
 305         // Keysyms for ASCII chars
 306         if (codepoint >= 0x0000 && codepoint <= 0x00FF)
 307             return codepoint;
 308
 309         // Keysyms for Unicode
 310         if (codepoint >= 0x0100 && codepoint <= 0x10FFFF)
 311             return 0x01000000 | codepoint;
 312
 313         return null;
 314
 315     }
 316
 317     function getKeySymFromKeyCode(keyCode) {
 318
 319         var keysym = null;
 320         if (!guac_keyboard.modifiers.shift) keysym = unshiftedKeySym[keyCode];
 321         else {
 322             keysym = shiftedKeySym[keyCode];
 323             if (keysym == null) keysym = unshiftedKeySym[keyCode];
 324         }
 325
 326         return keysym;
 327
 328     }
 329
 330
 331     // Sends a single keystroke over the network
 332     function sendKeyPressed(keysym) {
 333
 334         // Mark key as pressed
 335         guac_keyboard.pressed[keysym] = true;
 336
 337         // Send key event
 338         if (keysym != null && guac_keyboard.onkeydown)
 339             return guac_keyboard.onkeydown(keysym) != false;
 340
 341         return true;
 342
 343     }
 344
 345     // Sends a single keystroke over the network
 346     function sendKeyReleased(keysym) {
 347
 348         // Mark key as released
 349         guac_keyboard.pressed[keysym] = false;
 350
 351         // Send key event
 352         if (keysym != null && guac_keyboard.onkeyup)
 353             return guac_keyboard.onkeyup(keysym) != false;
 354
 355         return true;
 356
 357     }
 358
 359
 360     var expect_keypress = true;
 361     var keydown_code = null;
 362
 363     var deferred_keypress = null;
 364     var keydown_keysym = null;
 365     var keypress_keysym = null;
 366
 367     function handleKeyEvents() {
 368
 369         // Prefer keysym from keypress
 370         var keysym = keypress_keysym || keydown_keysym;
 371         var keynum = keydown_code;
 372
 373         if (keydownChar[keynum] != keysym) {
 374
 375             // If this button is already pressed, release first
 376             var lastKeyDownChar = keydownChar[keydown_code];
 377             if (lastKeyDownChar)
 378                 sendKeyReleased(lastKeyDownChar);
 379
 380             // Send event
 381             keydownChar[keynum] = keysym;
 382             sendKeyPressed(keysym);
 383
 384             // Clear old key repeat, if any.
 385             stopRepeat();
 386
 387             // Start repeating (if not a modifier key) after a short delay
 388             if (keynum != 16 && keynum != 17 && keynum != 18)
 389                 repeatKeyTimeoutId = setTimeout(function() { startRepeat(keysym); }, 500);
 390
 391         }
 392
 393         // Done with deferred key event
 394         deferred_keypress = null;
 395         keypress_keysym   = null;
 396         keydown_keysym    = null;
 397         keydown_code      = null;
 398
 399     }
 400
 401     function isTypable(keyIdentifier) {
 402
 403         // Find unicode prefix
 404         var unicodePrefixLocation = keyIdentifier.indexOf("U+");
 405         if (unicodePrefixLocation == -1)
 406             return false;
 407
 408         // Parse codepoint value
 409         var hex = keyIdentifier.substring(unicodePrefixLocation+2);
 410         var codepoint = parseInt(hex, 16);
 411
 412         // If control character, not typable
 413         if (isControlCharacter(codepoint)) return false;
 414
 415         // Otherwise, typable
 416         return true;
 417
 418     }
 419
 420     // When key pressed
 421     element.addEventListener("keydown", function(e) {
 422
 423         // Only intercept if handler set
 424         if (!guac_keyboard.onkeydown) return;
 425
 426         var keynum;
 427         if (window.event) keynum = window.event.keyCode;
 428         else if (e.which) keynum = e.which;
 429
 430         // Ignore any unknown key events
 431         if (keynum == 0 && !e.keyIdentifier) {
 432             e.preventDefault();
 433             return;
 434         }
 435
 436         expect_keypress = true;
 437
 438         // Ctrl/Alt/Shift
 439         if (keynum == 16)      guac_keyboard.modifiers.shift = true;
 440         else if (keynum == 17) guac_keyboard.modifiers.ctrl  = true;
 441         else if (keynum == 18) guac_keyboard.modifiers.alt   = true;
 442
 443         // Try to get keysym from keycode
 444         keydown_keysym = getKeySymFromKeyCode(keynum);
 445
 446         // If key is known from keycode, prevent default
 447         if (keydown_keysym)
 448             expect_keypress = false;
 449
 450         // Also try to get get keysym from keyIdentifier
 451         if (e.keyIdentifier) {
 452
 453             keydown_keysym = keydown_keysym ||
 454                 getKeySymFromKeyIdentifier(guac_keyboard.modifiers.shift, e.keyIdentifier);
 455
 456             // Prevent default if non-typable character or if modifier combination
 457             // likely to be eaten by browser otherwise (NOTE: We must not prevent
 458             // default for Ctrl+Alt, as that combination is commonly used for
 459             // AltGr. If we receive AltGr, we need to handle keypress, which
 460             // means we cannot cancel keydown).
 461             if (!isTypable(e.keyIdentifier)
 462                     || ( guac_keyboard.modifiers.ctrl && !guac_keyboard.modifiers.alt)
 463                     || (!guac_keyboard.modifiers.ctrl &&  guac_keyboard.modifiers.alt))
 464                 expect_keypress = false;
 465
 466         }
 467
 468         // Set keycode which will be associated with any future keypress
 469         keydown_code = keynum;
 470
 471         // If we expect to handle via keypress, set failsafe timeout and
 472         // wait for keypress.
 473         if (expect_keypress) {
 474             if (!deferred_keypress)
 475                 deferred_keypress = window.setTimeout(handleKeyEvents, 0);
 476         }
 477
 478         // Otherwise, handle now
 479         else {
 480             e.preventDefault();
 481             handleKeyEvents();
 482         }
 483
 484     }, true);
 485
 486     // When key pressed
 487     element.addEventListener("keypress", function(e) {
 488
 489         // Only intercept if handler set
 490         if (!guac_keyboard.onkeydown) return;
 491
 492         e.preventDefault();
 493
 494         // Do not handle if we weren't expecting this event (will have already
 495         // been handled by keydown)
 496         if (!expect_keypress) return;
 497
 498         var keynum;
 499         if (window.event) keynum = window.event.keyCode;
 500         else if (e.which) keynum = e.which;
 501
 502         keypress_keysym = getKeySymFromCharCode(keynum);
 503
 504         // If event identified as a typable character, and we're holding Ctrl+Alt,
 505         // assume Ctrl+Alt is actually AltGr, and release both.
 506         if (!isControlCharacter(keynum) && guac_keyboard.modifiers.ctrl && guac_keyboard.modifiers.alt) {
 507             sendKeyReleased(0xFFE3);
 508             sendKeyReleased(0xFFE9);
 509         }
 510
 511         // Clear timeout, if any
 512         if (deferred_keypress)
 513             window.clearTimeout(deferred_keypress);
 514
 515         // Handle event with all aggregated data
 516         handleKeyEvents();
 517
 518     }, true);
 519
 520     // When key released
 521     element.addEventListener("keyup", function(e) {
 522
 523         // Only intercept if handler set
 524         if (!guac_keyboard.onkeyup) return;
 525
 526         e.preventDefault();
 527
 528         var keynum;
 529         if (window.event) keynum = window.event.keyCode;
 530         else if (e.which) keynum = e.which;
 531
 532         // Ctrl/Alt/Shift
 533         if (keynum == 16)      guac_keyboard.modifiers.shift = false;
 534         else if (keynum == 17) guac_keyboard.modifiers.ctrl  = false;
 535         else if (keynum == 18) guac_keyboard.modifiers.alt   = false;
 536         else
 537             stopRepeat();
 538
 539         // Get corresponding character
 540         var lastKeyDownChar = keydownChar[keynum];
 541
 542         // Clear character record
 543         keydownChar[keynum] = null;
 544
 545         // Send release event
 546         sendKeyReleased(lastKeyDownChar);
 547
 548     }, true);
 549
 550     // When focus is lost, clear modifiers.
 551     element.addEventListener("blur", function() {
 552         guac_keyboard.modifiers.alt = false;
 553         guac_keyboard.modifiers.ctrl = false;
 554         guac_keyboard.modifiers.shift = false;
 555     }, true);
 556
 557 };