You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
69 lines
1.6 KiB
69 lines
1.6 KiB
var toString = Object.prototype.toString |
|
|
|
var isModern = ( |
|
typeof Buffer.alloc === 'function' && |
|
typeof Buffer.allocUnsafe === 'function' && |
|
typeof Buffer.from === 'function' |
|
) |
|
|
|
function isArrayBuffer (input) { |
|
return toString.call(input).slice(8, -1) === 'ArrayBuffer' |
|
} |
|
|
|
function fromArrayBuffer (obj, byteOffset, length) { |
|
byteOffset >>>= 0 |
|
|
|
var maxLength = obj.byteLength - byteOffset |
|
|
|
if (maxLength < 0) { |
|
throw new RangeError("'offset' is out of bounds") |
|
} |
|
|
|
if (length === undefined) { |
|
length = maxLength |
|
} else { |
|
length >>>= 0 |
|
|
|
if (length > maxLength) { |
|
throw new RangeError("'length' is out of bounds") |
|
} |
|
} |
|
|
|
return isModern |
|
? Buffer.from(obj.slice(byteOffset, byteOffset + length)) |
|
: new Buffer(new Uint8Array(obj.slice(byteOffset, byteOffset + length))) |
|
} |
|
|
|
function fromString (string, encoding) { |
|
if (typeof encoding !== 'string' || encoding === '') { |
|
encoding = 'utf8' |
|
} |
|
|
|
if (!Buffer.isEncoding(encoding)) { |
|
throw new TypeError('"encoding" must be a valid string encoding') |
|
} |
|
|
|
return isModern |
|
? Buffer.from(string, encoding) |
|
: new Buffer(string, encoding) |
|
} |
|
|
|
function bufferFrom (value, encodingOrOffset, length) { |
|
if (typeof value === 'number') { |
|
throw new TypeError('"value" argument must not be a number') |
|
} |
|
|
|
if (isArrayBuffer(value)) { |
|
return fromArrayBuffer(value, encodingOrOffset, length) |
|
} |
|
|
|
if (typeof value === 'string') { |
|
return fromString(value, encodingOrOffset) |
|
} |
|
|
|
return isModern |
|
? Buffer.from(value) |
|
: new Buffer(value) |
|
} |
|
|
|
module.exports = bufferFrom
|
|
|