30 lines
725 B
JavaScript
30 lines
725 B
JavaScript
/**
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* An abstraction for slicing an arraybuffer even when
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* ArrayBuffer.prototype.slice is not supported
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*
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* @api public
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*/
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module.exports = function(arraybuffer, start, end) {
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var bytes = arraybuffer.byteLength;
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start = start || 0;
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end = end || bytes;
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if (arraybuffer.slice) { return arraybuffer.slice(start, end); }
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if (start < 0) { start += bytes; }
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if (end < 0) { end += bytes; }
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if (end > bytes) { end = bytes; }
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if (start >= bytes || start >= end || bytes === 0) {
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return new ArrayBuffer(0);
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}
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var abv = new Uint8Array(arraybuffer);
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var result = new Uint8Array(end - start);
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for (var i = start, ii = 0; i < end; i++, ii++) {
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result[ii] = abv[i];
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}
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return result.buffer;
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};
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