@novnc/novnc
Version:
An HTML5 VNC client
175 lines (174 loc) • 8.23 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", {
value: true
});
exports["default"] = void 0;
function _typeof(o) { "@babel/helpers - typeof"; return _typeof = "function" == typeof Symbol && "symbol" == typeof Symbol.iterator ? function (o) { return typeof o; } : function (o) { return o && "function" == typeof Symbol && o.constructor === Symbol && o !== Symbol.prototype ? "symbol" : typeof o; }, _typeof(o); }
function _toConsumableArray(r) { return _arrayWithoutHoles(r) || _iterableToArray(r) || _unsupportedIterableToArray(r) || _nonIterableSpread(); }
function _nonIterableSpread() { throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
function _iterableToArray(r) { if ("undefined" != typeof Symbol && null != r[Symbol.iterator] || null != r["@@iterator"]) return Array.from(r); }
function _arrayWithoutHoles(r) { if (Array.isArray(r)) return _arrayLikeToArray(r); }
function _createForOfIteratorHelper(r, e) { var t = "undefined" != typeof Symbol && r[Symbol.iterator] || r["@@iterator"]; if (!t) { if (Array.isArray(r) || (t = _unsupportedIterableToArray(r)) || e && r && "number" == typeof r.length) { t && (r = t); var _n = 0, F = function F() {}; return { s: F, n: function n() { return _n >= r.length ? { done: !0 } : { done: !1, value: r[_n++] }; }, e: function e(r) { throw r; }, f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } var o, a = !0, u = !1; return { s: function s() { t = t.call(r); }, n: function n() { var r = t.next(); return a = r.done, r; }, e: function e(r) { u = !0, o = r; }, f: function f() { try { a || null == t["return"] || t["return"](); } finally { if (u) throw o; } } }; }
function _unsupportedIterableToArray(r, a) { if (r) { if ("string" == typeof r) return _arrayLikeToArray(r, a); var t = {}.toString.call(r).slice(8, -1); return "Object" === t && r.constructor && (t = r.constructor.name), "Map" === t || "Set" === t ? Array.from(r) : "Arguments" === t || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(t) ? _arrayLikeToArray(r, a) : void 0; } }
function _arrayLikeToArray(r, a) { (null == a || a > r.length) && (a = r.length); for (var e = 0, n = Array(a); e < a; e++) n[e] = r[e]; return n; }
function _classCallCheck(a, n) { if (!(a instanceof n)) throw new TypeError("Cannot call a class as a function"); }
function _defineProperties(e, r) { for (var t = 0; t < r.length; t++) { var o = r[t]; o.enumerable = o.enumerable || !1, o.configurable = !0, "value" in o && (o.writable = !0), Object.defineProperty(e, _toPropertyKey(o.key), o); } }
function _createClass(e, r, t) { return r && _defineProperties(e.prototype, r), t && _defineProperties(e, t), Object.defineProperty(e, "prototype", { writable: !1 }), e; }
function _toPropertyKey(t) { var i = _toPrimitive(t, "string"); return "symbol" == _typeof(i) ? i : i + ""; }
function _toPrimitive(t, r) { if ("object" != _typeof(t) || !t) return t; var e = t[Symbol.toPrimitive]; if (void 0 !== e) { var i = e.call(t, r || "default"); if ("object" != _typeof(i)) return i; throw new TypeError("@@toPrimitive must return a primitive value."); } return ("string" === r ? String : Number)(t); }
/*
* noVNC: HTML5 VNC client
* Copyright (C) 2019 The noVNC authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*
*/
var JPEGDecoder = exports["default"] = /*#__PURE__*/function () {
function JPEGDecoder() {
_classCallCheck(this, JPEGDecoder);
// RealVNC will reuse the quantization tables
// and Huffman tables, so we need to cache them.
this._cachedQuantTables = [];
this._cachedHuffmanTables = [];
this._segments = [];
}
return _createClass(JPEGDecoder, [{
key: "decodeRect",
value: function decodeRect(x, y, width, height, sock, display, depth) {
// A rect of JPEG encodings is simply a JPEG file
while (true) {
var segment = this._readSegment(sock);
if (segment === null) {
return false;
}
this._segments.push(segment);
// End of image?
if (segment[1] === 0xD9) {
break;
}
}
var huffmanTables = [];
var quantTables = [];
var _iterator = _createForOfIteratorHelper(this._segments),
_step;
try {
for (_iterator.s(); !(_step = _iterator.n()).done;) {
var _segment = _step.value;
var type = _segment[1];
if (type === 0xC4) {
// Huffman tables
huffmanTables.push(_segment);
} else if (type === 0xDB) {
// Quantization tables
quantTables.push(_segment);
}
}
} catch (err) {
_iterator.e(err);
} finally {
_iterator.f();
}
var sofIndex = this._segments.findIndex(function (x) {
return x[1] == 0xC0 || x[1] == 0xC2;
});
if (sofIndex == -1) {
throw new Error("Illegal JPEG image without SOF");
}
if (quantTables.length === 0) {
var _this$_segments;
(_this$_segments = this._segments).splice.apply(_this$_segments, [sofIndex + 1, 0].concat(_toConsumableArray(this._cachedQuantTables)));
}
if (huffmanTables.length === 0) {
var _this$_segments2;
(_this$_segments2 = this._segments).splice.apply(_this$_segments2, [sofIndex + 1, 0].concat(_toConsumableArray(this._cachedHuffmanTables)));
}
var length = 0;
var _iterator2 = _createForOfIteratorHelper(this._segments),
_step2;
try {
for (_iterator2.s(); !(_step2 = _iterator2.n()).done;) {
var _segment2 = _step2.value;
length += _segment2.length;
}
} catch (err) {
_iterator2.e(err);
} finally {
_iterator2.f();
}
var data = new Uint8Array(length);
length = 0;
var _iterator3 = _createForOfIteratorHelper(this._segments),
_step3;
try {
for (_iterator3.s(); !(_step3 = _iterator3.n()).done;) {
var _segment3 = _step3.value;
data.set(_segment3, length);
length += _segment3.length;
}
} catch (err) {
_iterator3.e(err);
} finally {
_iterator3.f();
}
display.imageRect(x, y, width, height, "image/jpeg", data);
if (huffmanTables.length !== 0) {
this._cachedHuffmanTables = huffmanTables;
}
if (quantTables.length !== 0) {
this._cachedQuantTables = quantTables;
}
this._segments = [];
return true;
}
}, {
key: "_readSegment",
value: function _readSegment(sock) {
if (sock.rQwait("JPEG", 2)) {
return null;
}
var marker = sock.rQshift8();
if (marker != 0xFF) {
throw new Error("Illegal JPEG marker received (byte: " + marker + ")");
}
var type = sock.rQshift8();
if (type >= 0xD0 && type <= 0xD9 || type == 0x01) {
// No length after marker
return new Uint8Array([marker, type]);
}
if (sock.rQwait("JPEG", 2, 2)) {
return null;
}
var length = sock.rQshift16();
if (length < 2) {
throw new Error("Illegal JPEG length received (length: " + length + ")");
}
if (sock.rQwait("JPEG", length - 2, 4)) {
return null;
}
var extra = 0;
if (type === 0xDA) {
// start of scan
extra += 2;
while (true) {
if (sock.rQwait("JPEG", length - 2 + extra, 4)) {
return null;
}
var data = sock.rQpeekBytes(length - 2 + extra, false);
if (data.at(-2) === 0xFF && data.at(-1) !== 0x00 && !(data.at(-1) >= 0xD0 && data.at(-1) <= 0xD7)) {
extra -= 2;
break;
}
extra++;
}
}
var segment = new Uint8Array(2 + length + extra);
segment[0] = marker;
segment[1] = type;
segment[2] = length >> 8;
segment[3] = length;
segment.set(sock.rQshiftBytes(length - 2 + extra, false), 4);
return segment;
}
}]);
}();