// Hex JavaScript decoder
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// Copyright (c) 2008-2013 Lapo Luchini <lapo@lapo.it>
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// Permission to use, copy, modify, and/or distribute this software for any
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// purpose with or without fee is hereby granted, provided that the above
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// copyright notice and this permission notice appear in all copies.
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//
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// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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/*jshint browser: true, strict: true, immed: true, latedef: true, undef: true, regexdash: false */
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var decoder;
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export var Hex = {
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decode: function (a) {
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var i;
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if (decoder === undefined) {
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var hex = "0123456789ABCDEF";
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var ignore = " \f\n\r\t\u00A0\u2028\u2029";
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decoder = {};
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for (i = 0; i < 16; ++i) {
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decoder[hex.charAt(i)] = i;
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}
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hex = hex.toLowerCase();
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for (i = 10; i < 16; ++i) {
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decoder[hex.charAt(i)] = i;
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}
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for (i = 0; i < ignore.length; ++i) {
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decoder[ignore.charAt(i)] = -1;
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}
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}
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var out = [];
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var bits = 0;
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var char_count = 0;
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for (i = 0; i < a.length; ++i) {
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var c = a.charAt(i);
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if (c == "=") {
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break;
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}
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c = decoder[c];
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if (c == -1) {
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continue;
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}
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if (c === undefined) {
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throw new Error("Illegal character at offset " + i);
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}
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bits |= c;
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if (++char_count >= 2) {
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out[out.length] = bits;
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bits = 0;
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char_count = 0;
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}
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else {
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bits <<= 4;
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}
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}
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if (char_count) {
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throw new Error("Hex encoding incomplete: 4 bits missing");
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}
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return out;
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}
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};
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