27 lines
672 B
TypeScript
27 lines
672 B
TypeScript
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// Copyright 2024 Signal Messenger, LLC
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// SPDX-License-Identifier: AGPL-3.0-only
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import { Transform } from 'node:stream';
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/**
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* Truncates the stream to the target size.
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*/
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export function trimPadding(size: number): Transform {
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let total = 0;
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return new Transform({
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transform(chunk, _encoding, callback) {
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const chunkSize = chunk.byteLength;
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const sizeLeft = size - total;
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if (sizeLeft >= chunkSize) {
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total += chunkSize;
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callback(null, chunk);
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} else if (sizeLeft > 0) {
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total += sizeLeft;
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callback(null, chunk.subarray(0, sizeLeft));
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} else {
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callback(null, null);
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}
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},
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});
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}
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