20 lines
574 B
JavaScript
20 lines
574 B
JavaScript
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const MAP_HEX = {
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0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5, 6: 6,
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7: 7, 8: 8, 9: 9, a: 10, b: 11, c: 12, d: 13,
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e: 14, f: 15, A: 10, B: 11, C: 12, D: 13,
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E: 14, F: 15
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};
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export function fromHex(hexString) {
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const bytes = new Uint8Array(Math.floor((hexString || "").length / 2));
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let i;
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for (i = 0; i < bytes.length; i++) {
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const a = MAP_HEX[hexString[i * 2]];
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const b = MAP_HEX[hexString[i * 2 + 1]];
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if (a === undefined || b === undefined) {
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break;
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}
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bytes[i] = (a << 4) | b;
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}
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return i === bytes.length ? bytes : bytes.slice(0, i);
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}
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