40 lines
880 B
TypeScript
40 lines
880 B
TypeScript
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import { typedArrayToBuffer } from '../buffer-utils'
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import { Data, Deflate, inflate } from 'pako'
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export function gzipInflate(buf: Buffer): Buffer {
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return typedArrayToBuffer(inflate(buf))
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}
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class DeflateLimited extends Deflate {
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constructor(readonly limit: number) {
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super()
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}
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_size = 0
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onData(chunk: Data) {
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this._size += chunk.length
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if (this._size > this.limit) {
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throw 'ERR_SIZE'
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}
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super.onData(chunk)
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}
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}
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export function gzipDeflate(buf: Buffer, maxRatio?: number): Buffer | null {
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const deflator = maxRatio
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? new DeflateLimited(Math.floor(buf.length * maxRatio))
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: new Deflate()
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try {
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deflator.push(buf, true)
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} catch (e) {
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if (e === 'ERR_SIZE') return null
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throw e
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}
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return typedArrayToBuffer(deflator.result as Uint8Array)
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}
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