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1
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var Buffer = require('buffer').Buffer
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|
2
|
|
|
3
|
module.exports = function (buf) {
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|
4
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// If the buffer is backed by a Uint8Array, a faster version will work
|
|
5
|
if (buf instanceof Uint8Array) {
|
|
6
|
// If the buffer isn't a subarray, return the underlying ArrayBuffer
|
|
7
|
if (buf.byteOffset === 0 && buf.byteLength === buf.buffer.byteLength) {
|
|
8
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return buf.buffer
|
|
9
|
} else if (typeof buf.buffer.slice === 'function') {
|
|
10
|
// Otherwise we need to get a proper copy
|
|
11
|
return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength)
|
|
12
|
}
|
|
13
|
}
|
|
14
|
|
|
15
|
if (Buffer.isBuffer(buf)) {
|
|
16
|
// This is the slow version that will work with any Buffer
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|
17
|
// implementation (even in old browsers)
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|
18
|
var arrayCopy = new Uint8Array(buf.length)
|
|
19
|
var len = buf.length
|
|
20
|
for (var i = 0; i < len; i++) {
|
|
21
|
arrayCopy[i] = buf[i]
|
|
22
|
}
|
|
23
|
return arrayCopy.buffer
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|
24
|
} else {
|
|
25
|
throw new Error('Argument must be a Buffer')
|
|
26
|
}
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|
27
|
}
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