Update noVNC to 1.4.0

public/novnc/core/decoders/zrle.js

@@ -0,0 +1,185 @@
+/*
+ * noVNC: HTML5 VNC client
+ * Copyright (C) 2021 The noVNC Authors
+ * Licensed under MPL 2.0 (see LICENSE.txt)
+ *
+ * See README.md for usage and integration instructions.
+ *
+ */
+
+import Inflate from "../inflator.js";
+
+const ZRLE_TILE_WIDTH = 64;
+const ZRLE_TILE_HEIGHT = 64;
+
+export default class ZRLEDecoder {
+    constructor() {
+        this._length = 0;
+        this._inflator = new Inflate();
+
+        this._pixelBuffer = new Uint8Array(ZRLE_TILE_WIDTH * ZRLE_TILE_HEIGHT * 4);
+        this._tileBuffer = new Uint8Array(ZRLE_TILE_WIDTH * ZRLE_TILE_HEIGHT * 4);
+    }
+
+    decodeRect(x, y, width, height, sock, display, depth) {
+        if (this._length === 0) {
+            if (sock.rQwait("ZLib data length", 4)) {
+                return false;
+            }
+            this._length = sock.rQshift32();
+        }
+        if (sock.rQwait("Zlib data", this._length)) {
+            return false;
+        }
+
+        const data = sock.rQshiftBytes(this._length);
+
+        this._inflator.setInput(data);
+
+        for (let ty = y; ty < y + height; ty += ZRLE_TILE_HEIGHT) {
+            let th = Math.min(ZRLE_TILE_HEIGHT, y + height - ty);
+
+            for (let tx = x; tx < x + width; tx += ZRLE_TILE_WIDTH) {
+                let tw = Math.min(ZRLE_TILE_WIDTH, x + width - tx);
+
+                const tileSize = tw * th;
+                const subencoding = this._inflator.inflate(1)[0];
+                if (subencoding === 0) {
+                    // raw data
+                    const data = this._readPixels(tileSize);
+                    display.blitImage(tx, ty, tw, th, data, 0, false);
+                } else if (subencoding === 1) {
+                    // solid
+                    const background = this._readPixels(1);
+                    display.fillRect(tx, ty, tw, th, [background[0], background[1], background[2]]);
+                } else if (subencoding >= 2 && subencoding <= 16) {
+                    const data = this._decodePaletteTile(subencoding, tileSize, tw, th);
+                    display.blitImage(tx, ty, tw, th, data, 0, false);
+                } else if (subencoding === 128) {
+                    const data = this._decodeRLETile(tileSize);
+                    display.blitImage(tx, ty, tw, th, data, 0, false);
+                } else if (subencoding >= 130 && subencoding <= 255) {
+                    const data = this._decodeRLEPaletteTile(subencoding - 128, tileSize);
+                    display.blitImage(tx, ty, tw, th, data, 0, false);
+                } else {
+                    throw new Error('Unknown subencoding: ' + subencoding);
+                }
+            }
+        }
+        this._length = 0;
+        return true;
+    }
+
+    _getBitsPerPixelInPalette(paletteSize) {
+        if (paletteSize <= 2) {
+            return 1;
+        } else if (paletteSize <= 4) {
+            return 2;
+        } else if (paletteSize <= 16) {
+            return 4;
+        }
+    }
+
+    _readPixels(pixels) {
+        let data = this._pixelBuffer;
+        const buffer = this._inflator.inflate(3*pixels);
+        for (let i = 0, j = 0; i < pixels*4; i += 4, j += 3) {
+            data[i]     = buffer[j];
+            data[i + 1] = buffer[j + 1];
+            data[i + 2] = buffer[j + 2];
+            data[i + 3] = 255;  // Add the Alpha
+        }
+        return data;
+    }
+
+    _decodePaletteTile(paletteSize, tileSize, tilew, tileh) {
+        const data = this._tileBuffer;
+        const palette = this._readPixels(paletteSize);
+        const bitsPerPixel = this._getBitsPerPixelInPalette(paletteSize);
+        const mask = (1 << bitsPerPixel) - 1;
+
+        let offset = 0;
+        let encoded = this._inflator.inflate(1)[0];
+
+        for (let y=0; y<tileh; y++) {
+            let shift = 8-bitsPerPixel;
+            for (let x=0; x<tilew; x++) {
+                if (shift<0) {
+                    shift=8-bitsPerPixel;
+                    encoded = this._inflator.inflate(1)[0];
+                }
+                let indexInPalette = (encoded>>shift) & mask;
+
+                data[offset] = palette[indexInPalette * 4];
+                data[offset + 1] = palette[indexInPalette * 4 + 1];
+                data[offset + 2] = palette[indexInPalette * 4 + 2];
+                data[offset + 3] = palette[indexInPalette * 4 + 3];
+                offset += 4;
+                shift-=bitsPerPixel;
+            }
+            if (shift<8-bitsPerPixel && y<tileh-1) {
+                encoded =  this._inflator.inflate(1)[0];
+            }
+        }
+        return data;
+    }
+
+    _decodeRLETile(tileSize) {
+        const data = this._tileBuffer;
+        let i = 0;
+        while (i < tileSize) {
+            const pixel = this._readPixels(1);
+            const length = this._readRLELength();
+            for (let j = 0; j < length; j++) {
+                data[i * 4] = pixel[0];
+                data[i * 4 + 1] = pixel[1];
+                data[i * 4 + 2] = pixel[2];
+                data[i * 4 + 3] = pixel[3];
+                i++;
+            }
+        }
+        return data;
+    }
+
+    _decodeRLEPaletteTile(paletteSize, tileSize) {
+        const data = this._tileBuffer;
+
+        // palette
+        const palette = this._readPixels(paletteSize);
+
+        let offset = 0;
+        while (offset < tileSize) {
+            let indexInPalette = this._inflator.inflate(1)[0];
+            let length = 1;
+            if (indexInPalette >= 128) {
+                indexInPalette -= 128;
+                length = this._readRLELength();
+            }
+            if (indexInPalette > paletteSize) {
+                throw new Error('Too big index in palette: ' + indexInPalette + ', palette size: ' + paletteSize);
+            }
+            if (offset + length > tileSize) {
+                throw new Error('Too big rle length in palette mode: ' + length + ', allowed length is: ' + (tileSize - offset));
+            }
+
+            for (let j = 0; j < length; j++) {
+                data[offset * 4] = palette[indexInPalette * 4];
+                data[offset * 4 + 1] = palette[indexInPalette * 4 + 1];
+                data[offset * 4 + 2] = palette[indexInPalette * 4 + 2];
+                data[offset * 4 + 3] = palette[indexInPalette * 4 + 3];
+                offset++;
+            }
+        }
+        return data;
+    }
+
+    _readRLELength() {
+        let length = 0;
+        let current = 0;
+        do {
+            current = this._inflator.inflate(1)[0];
+            length += current;
+        } while (current === 255);
+        return length + 1;
+    }
+}