66 lines
2.2 KiB
JavaScript
66 lines
2.2 KiB
JavaScript
// original source: https://github.com/niklasvh/base64-arraybuffer/blob/master/src/index.ts
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"use strict";
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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0 && (module.exports = {
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encode: null,
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decode: null
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});
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function _export(target, all) {
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for(var name in all)Object.defineProperty(target, name, {
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enumerable: true,
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get: all[name]
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});
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}
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_export(exports, {
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encode: function() {
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return encode;
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},
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decode: function() {
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return decode;
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}
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});
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const chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
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// Use a lookup table to find the index.
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const lookup = typeof Uint8Array === "undefined" ? [] : new Uint8Array(256);
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for(let i = 0; i < chars.length; i++){
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lookup[chars.charCodeAt(i)] = i;
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}
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const encode = (arraybuffer)=>{
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let bytes = new Uint8Array(arraybuffer), i, len = bytes.length, base64 = "";
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for(i = 0; i < len; i += 3){
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base64 += chars[bytes[i] >> 2];
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base64 += chars[(bytes[i] & 3) << 4 | bytes[i + 1] >> 4];
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base64 += chars[(bytes[i + 1] & 15) << 2 | bytes[i + 2] >> 6];
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base64 += chars[bytes[i + 2] & 63];
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}
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if (len % 3 === 2) {
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base64 = base64.substring(0, base64.length - 1) + "=";
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} else if (len % 3 === 1) {
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base64 = base64.substring(0, base64.length - 2) + "==";
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}
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return base64;
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};
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const decode = (base64)=>{
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let bufferLength = base64.length * 0.75, len = base64.length, i, p = 0, encoded1, encoded2, encoded3, encoded4;
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if (base64[base64.length - 1] === "=") {
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bufferLength--;
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if (base64[base64.length - 2] === "=") {
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bufferLength--;
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}
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}
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const arraybuffer = new ArrayBuffer(bufferLength), bytes = new Uint8Array(arraybuffer);
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for(i = 0; i < len; i += 4){
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encoded1 = lookup[base64.charCodeAt(i)];
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encoded2 = lookup[base64.charCodeAt(i + 1)];
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encoded3 = lookup[base64.charCodeAt(i + 2)];
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encoded4 = lookup[base64.charCodeAt(i + 3)];
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bytes[p++] = encoded1 << 2 | encoded2 >> 4;
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bytes[p++] = (encoded2 & 15) << 4 | encoded3 >> 2;
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bytes[p++] = (encoded3 & 3) << 6 | encoded4 & 63;
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}
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return arraybuffer;
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};
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//# sourceMappingURL=base64-arraybuffer.js.map
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