36 lines
991 B
JavaScript
36 lines
991 B
JavaScript
|
import { assertTypedArray } from './assert.js'
|
||
|
|
|
||
|
|
const Buffer = globalThis.Buffer // Buffer is optional
|
||
|
|
|
||
|
|
export function typedView(arr, format) {
|
||
|
|
assertTypedArray(arr)
|
||
|
|
switch (format) {
|
||
|
|
case 'uint8':
|
||
|
|
if (arr.constructor === Uint8Array) return arr // fast path
|
||
|
|
return new Uint8Array(arr.buffer, arr.byteOffset, arr.byteLength)
|
||
|
|
case 'buffer':
|
||
|
|
if (arr.constructor === Buffer && Buffer.isBuffer(arr)) return arr
|
||
|
|
return Buffer.from(arr.buffer, arr.byteOffset, arr.byteLength)
|
||
|
|
}
|
||
|
|
|
||
|
|
throw new TypeError('Unexpected format')
|
||
|
|
}
|
||
|
|
|
||
|
|
export function typedCopyBytes(arr, format) {
|
||
|
|
assertTypedArray(arr)
|
||
|
|
if (!(arr instanceof Uint8Array)) {
|
||
|
|
arr = new Uint8Array(arr.buffer, arr.byteOffset, arr.byteLength)
|
||
|
|
}
|
||
|
|
|
||
|
|
switch (format) {
|
||
|
|
case 'uint8':
|
||
|
|
return Uint8Array.from(arr) // never pooled
|
||
|
|
case 'buffer':
|
||
|
|
return Buffer.from(arr)
|
||
|
|
case 'arraybuffer':
|
||
|
|
return Uint8Array.from(arr).buffer
|
||
|
|
}
|
||
|
|
|
||
|
|
throw new TypeError('Unexpected format')
|
||
|
|
}
|