/*! * The buffer module from node.js, for the browser. * * @author Feross Aboukhadijeh * @license MIT */ /* eslint-disable no-proto */ 'use strict' var base64 = require('base64-js') var ieee754 = require('ieee754') var isArray = require('isarray') exports.Buffer = Buffer exports.SlowBuffer = SlowBuffer exports.INSPECT_MAX_BYTES = 50 /** * If `Buffer.TYPED_ARRAY_SUPPORT`: * === true Use Uint8Array implementation (fastest) * === false Use Object implementation (most compatible, even IE6) * * Browsers that support typed arrays are IE 10+, Firefox 4+, Chrome 7+, Safari 5.1+, * Opera 11.6+, iOS 4.2+. * * Due to various browser bugs, sometimes the Object implementation will be used even * when the browser supports typed arrays. * * Note: * * - Firefox 4-29 lacks support for adding new properties to `Uint8Array` instances, * See: https://bugzilla.mozilla.org/show_bug.cgi?id=695438. * * - Chrome 9-10 is missing the `TypedArray.prototype.subarray` function. * * - IE10 has a broken `TypedArray.prototype.subarray` function which returns arrays of * incorrect length in some situations. * We detect these buggy browsers and set `Buffer.TYPED_ARRAY_SUPPORT` to `false` so they * get the Object implementation, which is slower but behaves correctly. */ Buffer.TYPED_ARRAY_SUPPORT = global.TYPED_ARRAY_SUPPORT !== undefined ? global.TYPED_ARRAY_SUPPORT : typedArraySupport() /* * Export kMaxLength after typed array support is determined. */ exports.kMaxLength = kMaxLength() function typedArraySupport () { try { var arr = new Uint8Array(1) arr.__proto__ = {__proto__: Uint8Array.prototype, foo: function () { return 42 }} return arr.foo() === 42 && // typed array instances can be augmented typeof arr.subarray === 'function' && // chrome 9-10 lack `subarray` arr.subarray(1, 1).byteLength === 0 // ie10 has broken `subarray` } catch (e) { return false } } function kMaxLength () { return Buffer.TYPED_ARRAY_SUPPORT ? 0x7fffffff : 0x3fffffff } function createBuffer (that, length) { if (kMaxLength() < length) { throw new RangeError('Invalid typed array length') } if (Buffer.TYPED_ARRAY_SUPPORT) { // Return an augmented `Uint8Array` instance, for best performance that = new Uint8Array(length) that.__proto__ = Buffer.prototype } else { // Fallback: Return an object instance of the Buffer class if (that === null) { that = new Buffer(length) } that.length = length } return that } /** * The Buffer constructor returns instances of `Uint8Array` that have their * prototype changed to `Buffer.prototype`. Furthermore, `Buffer` is a subclass of * `Uint8Array`, so the returned instances will have all the node `Buffer` methods * and the `Uint8Array` methods. Square bracket notation works as expected -- it * returns a single octet. * * The `Uint8Array` prototype remains unmodified. */ function Buffer (arg, encodingOrOffset, length) { if (!Buffer.TYPED_ARRAY_SUPPORT && !(this instanceof Buffer)) { return new Buffer(arg, encodingOrOffset, length) } // Common case. if (typeof arg === 'number') { if (typeof encodingOrOffset === 'string') { throw new Error( 'If encoding is specified then the first argument must be a string' ) } return allocUnsafe(this, arg) } return from(this, arg, encodingOrOffset, length) } Buffer.poolSize = 8192 // not used by this implementation // TODO: Legacy, not needed anymore. Remove in next major version. Buffer._augment = function (arr) { arr.__proto__ = Buffer.prototype return arr } function from (that, value, encodingOrOffset, length) { if (typeof value === 'number') { throw new TypeError('"value" argument must not be a number') } if (typeof ArrayBuffer !== 'undefined' && value instanceof ArrayBuffer) { return fromArrayBuffer(that, value, encodingOrOffset, length) } if (typeof value === 'string') { return fromString(that, value, encodingOrOffset) } return fromObject(that, value) } /** * Functionally equivalent to Buffer(arg, encoding) but throws a TypeError * if value is a number. * Buffer.from(str[, encoding]) * Buffer.from(array) * Buffer.from(buffer) * Buffer.from(arrayBuffer[, byteOffset[, length]]) **/ Buffer.from = function (value, encodingOrOffset, length) { return from(null, value, encodingOrOffset, length) } if (Buffer.TYPED_ARRAY_SUPPORT) { Buffer.prototype.__proto__ = Uint8Array.prototype Buffer.__proto__ = Uint8Array if (typeof Symbol !== 'undefined' && Symbol.species && Buffer[Symbol.species] === Buffer) { // Fix subarray() in ES2016. See: https://github.com/feross/buffer/pull/97 Object.defineProperty(Buffer, Symbol.species, { value: null, configurable: true }) } } function assertSize (size) { if (typeof size !== 'number') { throw new TypeError('"size" argument must be a number') } else if (size < 0) { throw new RangeError('"size" argument must not be negative') } } function alloc (that, size, fill, encoding) { assertSize(size) if (size <= 0) { return createBuffer(that, size) } if (fill !== undefined) { // Only pay attention to encoding if it's a string. This // prevents accidentally sending in a number that would // be interpretted as a start offset. return typeof encoding === 'string' ? createBuffer(that, size).fill(fill, encoding) : createBuffer(that, size).fill(fill) } return createBuffer(that, size) } /** * Creates a new filled Buffer instance. * alloc(size[, fill[, encoding]]) **/ Buffer.alloc = function (size, fill, encoding) { return alloc(null, size, fill, encoding) } function allocUnsafe (that, size) { assertSize(size) that = createBuffer(that, size < 0 ? 0 : checked(size) | 0) if (!Buffer.TYPED_ARRAY_SUPPORT) { for (var i = 0; i < size; ++i) { that[i] = 0 } } return that } /** * Equivalent to Buffer(num), by default creates a non-zero-filled Buffer instance. * */ Buffer.allocUnsafe = function (size) { return allocUnsafe(null, size) } /** * Equivalent to SlowBuffer(num), by default creates a non-zero-filled Buffer instance. */ Buffer.allocUnsafeSlow = function (size) { return allocUnsafe(null, size) } function fromString (that, string, encoding) { if (typeof encoding !== 'string' || encoding === '') { encoding = 'utf8' } if (!Buffer.isEncoding(encoding)) { throw new TypeError('"encoding" must be a valid string encoding') } var length = byteLength(string, encoding) | 0 that = createBuffer(that, length) var actual = that.write(string, encoding) if (actual !== length) { // Writing a hex string, for example, that contains invalid characters will // cause everything after the first invalid character to be ignored. (e.g. // 'abxxcd' will be treated as 'ab') that = that.slice(0, actual) } return that } function fromArrayLike (that, array) { var length = array.length < 0 ? 0 : checked(array.length) | 0 that = createBuffer(that, length) for (var i = 0; i < length; i += 1) { that[i] = array[i] & 255 } return that } function fromArrayBuffer (that, array, byteOffset, length) { array.byteLength // this throws if `array` is not a valid ArrayBuffer if (byteOffset < 0 || array.byteLength < byteOffset) { throw new RangeError('\'offset\' is out of bounds') } if (array.byteLength < byteOffset + (length || 0)) { throw new RangeError('\'length\' is out of bounds') } if (byteOffset === undefined && length === undefined) { array = new Uint8Array(array) } else if (length === undefined) { array = new Uint8Array(array, byteOffset) } else { array = new Uint8Array(array, byteOffset, length) } if (Buffer.TYPED_ARRAY_SUPPORT) { // Return an augmented `Uint8Array` instance, for best performance that = array that.__proto__ = Buffer.prototype } else { // Fallback: Return an object instance of the Buffer class that = fromArrayLike(that, array) } return that } function fromObject (that, obj) { if (Buffer.isBuffer(obj)) { var len = checked(obj.length) | 0 that = createBuffer(that, len) if (that.length === 0) { return that } obj.copy(that, 0, 0, len) return that } if (obj) { if ((typeof ArrayBuffer !== 'undefined' && obj.buffer instanceof ArrayBuffer) || 'length' in obj) { if (typeof obj.length !== 'number' || isnan(obj.length)) { return createBuffer(that, 0) } return fromArrayLike(that, obj) } if (obj.type === 'Buffer' && isArray(obj.data)) { return fromArrayLike(that, obj.data) } } throw new TypeError('First argument must be a string, Buffer, ArrayBuffer, Array, or array-like object.') } function checked (length) { // Note: cannot use `length < kMaxLength()` here because that fails when // length is NaN (which is otherwise coerced to zero.) if (length >= kMaxLength()) { throw new RangeError('Attempt to allocate Buffer larger than maximum ' + 'size: 0x' + kMaxLength().toString(16) + ' bytes') } return length | 0 } function SlowBuffer (length) { if (+length != length) { // eslint-disable-line eqeqeq length = 0 } return Buffer.alloc(+length) } Buffer.isBuffer = function isBuffer (b) { return !!(b != null && b._isBuffer) } Buffer.compare = function compare (a, b) { if (!Buffer.isBuffer(a) || !Buffer.isBuffer(b)) { throw new TypeError('Arguments must be Buffers') } if (a === b) return 0 var x = a.length var y = b.length for (var i = 0, len = Math.min(x, y); i < len; ++i) { if (a[i] !== b[i]) { x = a[i] y = b[i] break } } if (x < y) return -1 if (y < x) return 1 return 0 } Buffer.isEncoding = function isEncoding (encoding) { switch (String(encoding).toLowerCase()) { case 'hex': case 'utf8': case 'utf-8': case 'ascii': case 'latin1': case 'binary': case 'base64': case 'ucs2': case 'ucs-2': case 'utf16le': case 'utf-16le': return true default: return false } } Buffer.concat = function concat (list, length) { if (!isArray(list)) { throw new TypeError('"list" argument must be an Array of Buffers') } if (list.length === 0) { return Buffer.alloc(0) } var i if (length === undefined) { length = 0 for (i = 0; i < list.length; ++i) { length += list[i].length } } var buffer = Buffer.allocUnsafe(length) var pos = 0 for (i = 0; i < list.length; ++i) { var buf = list[i] if (!Buffer.isBuffer(buf)) { throw new TypeError('"list" argument must be an Array of Buffers') } buf.copy(buffer, pos) pos += buf.length } return buffer } function byteLength (string, encoding) { if (Buffer.isBuffer(string)) { return string.length } if (typeof ArrayBuffer !== 'undefined' && typeof ArrayBuffer.isView === 'function' && (ArrayBuffer.isView(string) || string instanceof ArrayBuffer)) { return string.byteLength } if (typeof string !== 'string') { string = '' + string } var len = string.length if (len === 0) return 0 // Use a for loop to avoid recursion var loweredCase = false for (;;) { switch (encoding) { case 'ascii': case 'latin1': case 'binary': return len case 'utf8': case 'utf-8': case undefined: return utf8ToBytes(string).length case 'ucs2': case 'ucs-2': case 'utf16le': case 'utf-16le': return len * 2 case 'hex': return len >>> 1 case 'base64': return base64ToBytes(string).length default: if (loweredCase) return utf8ToBytes(string).length // assume utf8 encoding = ('' + encoding).toLowerCase() loweredCase = true } } } Buffer.byteLength = byteLength function slowToString (encoding, start, end) { var loweredCase = false // No need to verify that "this.length <= MAX_UINT32" since it's a read-only // property of a typed array. // This behaves neither like String nor Uint8Array in that we set start/end // to their upper/lower bounds if the value passed is out of range. // undefined is handled specially as per ECMA-262 6th Edition, // Section 13.3.3.7 Runtime Semantics: KeyedBindingInitialization. if (start === undefined || start < 0) { start = 0 } // Return early if start > this.length. Done here to prevent potential uint32 // coercion fail below. if (start > this.length) { return '' } if (end === undefined || end > this.length) { end = this.length } if (end <= 0) { return '' } // Force coersion to uint32. This will also coerce falsey/NaN values to 0. end >>>= 0 start >>>= 0 if (end <= start) { return '' } if (!encoding) encoding = 'utf8' while (true) { switch (encoding) { case 'hex': return hexSlice(this, start, end) case 'utf8': case 'utf-8': return utf8Slice(this, start, end) case 'ascii': return asciiSlice(this, start, end) case 'latin1': case 'binary': return latin1Slice(this, start, end) case 'base64': return base64Slice(this, start, end) case 'ucs2': case 'ucs-2': case 'utf16le': case 'utf-16le': return utf16leSlice(this, start, end) default: if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding) encoding = (encoding + '').toLowerCase() loweredCase = true } } } // The property is used by `Buffer.isBuffer` and `is-buffer` (in Safari 5-7) to detect // Buffer instances. Buffer.prototype._isBuffer = true function swap (b, n, m) { var i = b[n] b[n] = b[m] b[m] = i } Buffer.prototype.swap16 = function swap16 () { var len = this.length if (len % 2 !== 0) { throw new RangeError('Buffer size must be a multiple of 16-bits') } for (var i = 0; i < len; i += 2) { swap(this, i, i + 1) } return this } Buffer.prototype.swap32 = function swap32 () { var len = this.length if (len % 4 !== 0) { throw new RangeError('Buffer size must be a multiple of 32-bits') } for (var i = 0; i < len; i += 4) { swap(this, i, i + 3) swap(this, i + 1, i + 2) } return this } Buffer.prototype.swap64 = function swap64 () { var len = this.length if (len % 8 !== 0) { throw new RangeError('Buffer size must be a multiple of 64-bits') } for (var i = 0; i < len; i += 8) { swap(this, i, i + 7) swap(this, i + 1, i + 6) swap(this, i + 2, i + 5) swap(this, i + 3, i + 4) } return this } Buffer.prototype.toString = function toString () { var length = this.length | 0 if (length === 0) return '' if (arguments.length === 0) return utf8Slice(this, 0, length) return slowToString.apply(this, arguments) } Buffer.prototype.equals = function equals (b) { if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer') if (this === b) return true return Buffer.compare(this, b) === 0 } Buffer.prototype.inspect = function inspect () { var str = '' var max = exports.INSPECT_MAX_BYTES if (this.length > 0) { str = this.toString('hex', 0, max).match(/.{2}/g).join(' ') if (this.length > max) str += ' ... ' } return '' } Buffer.prototype.compare = function compare (target, start, end, thisStart, thisEnd) { if (!Buffer.isBuffer(target)) { throw new TypeError('Argument must be a Buffer') } if (start === undefined) { start = 0 } if (end === undefined) { end = target ? target.length : 0 } if (thisStart === undefined) { thisStart = 0 } if (thisEnd === undefined) { thisEnd = this.length } if (start < 0 || end > target.length || thisStart < 0 || thisEnd > this.length) { throw new RangeError('out of range index') } if (thisStart >= thisEnd && start >= end) { return 0 } if (thisStart >= thisEnd) { return -1 } if (start >= end) { return 1 } start >>>= 0 end >>>= 0 thisStart >>>= 0 thisEnd >>>= 0 if (this === target) return 0 var x = thisEnd - thisStart var y = end - start var len = Math.min(x, y) var thisCopy = this.slice(thisStart, thisEnd) var targetCopy = target.slice(start, end) for (var i = 0; i < len; ++i) { if (thisCopy[i] !== targetCopy[i]) { x = thisCopy[i] y = targetCopy[i] break } } if (x < y) return -1 if (y < x) return 1 return 0 } // Finds either the first index of `val` in `buffer` at offset >= `byteOffset`, // OR the last index of `val` in `buffer` at offset <= `byteOffset`. // // Arguments: // - buffer - a Buffer to search // - val - a string, Buffer, or number // - byteOffset - an index into `buffer`; will be clamped to an int32 // - encoding - an optional encoding, relevant is val is a string // - dir - true for indexOf, false for lastIndexOf function bidirectionalIndexOf (buffer, val, byteOffset, encoding, dir) { // Empty buffer means no match if (buffer.length === 0) return -1 // Normalize byteOffset if (typeof byteOffset === 'string') { encoding = byteOffset byteOffset = 0 } else if (byteOffset > 0x7fffffff) { byteOffset = 0x7fffffff } else if (byteOffset < -0x80000000) { byteOffset = -0x80000000 } byteOffset = +byteOffset // Coerce to Number. if (isNaN(byteOffset)) { // byteOffset: it it's undefined, null, NaN, "foo", etc, search whole buffer byteOffset = dir ? 0 : (buffer.length - 1) } // Normalize byteOffset: negative offsets start from the end of the buffer if (byteOffset < 0) byteOffset = buffer.length + byteOffset if (byteOffset >= buffer.length) { if (dir) return -1 else byteOffset = buffer.length - 1 } else if (byteOffset < 0) { if (dir) byteOffset = 0 else return -1 } // Normalize val if (typeof val === 'string') { val = Buffer.from(val, encoding) } // Finally, search either indexOf (if dir is true) or lastIndexOf if (Buffer.isBuffer(val)) { // Special case: looking for empty string/buffer always fails if (val.length === 0) { return -1 } return arrayIndexOf(buffer, val, byteOffset, encoding, dir) } else if (typeof val === 'number') { val = val & 0xFF // Search for a byte value [0-255] if (Buffer.TYPED_ARRAY_SUPPORT && typeof Uint8Array.prototype.indexOf === 'function') { if (dir) { return Uint8Array.prototype.indexOf.call(buffer, val, byteOffset) } else { return Uint8Array.prototype.lastIndexOf.call(buffer, val, byteOffset) } } return arrayIndexOf(buffer, [ val ], byteOffset, encoding, dir) } throw new TypeError('val must be string, number or Buffer') } function arrayIndexOf (arr, val, byteOffset, encoding, dir) { var indexSize = 1 var arrLength = arr.length var valLength = val.length if (encoding !== undefined) { encoding = String(encoding).toLowerCase() if (encoding === 'ucs2' || encoding === 'ucs-2' || encoding === 'utf16le' || encoding === 'utf-16le') { if (arr.length < 2 || val.length < 2) { return -1 } indexSize = 2 arrLength /= 2 valLength /= 2 byteOffset /= 2 } } function read (buf, i) { if (indexSize === 1) { return buf[i] } else { return buf.readUInt16BE(i * indexSize) } } var i if (dir) { var foundIndex = -1 for (i = byteOffset; i < arrLength; i++) { if (read(arr, i) === read(val, foundIndex === -1 ? 0 : i - foundIndex)) { if (foundIndex === -1) foundIndex = i if (i - foundIndex + 1 === valLength) return foundIndex * indexSize } else { if (foundIndex !== -1) i -= i - foundIndex foundIndex = -1 } } } else { if (byteOffset + valLength > arrLength) byteOffset = arrLength - valLength for (i = byteOffset; i >= 0; i--) { var found = true for (var j = 0; j < valLength; j++) { if (read(arr, i + j) !== read(val, j)) { found = false break } } if (found) return i } } return -1 } Buffer.prototype.includes = function includes (val, byteOffset, encoding) { return this.indexOf(val, byteOffset, encoding) !== -1 } Buffer.prototype.indexOf = function indexOf (val, byteOffset, encoding) { return bidirectionalIndexOf(this, val, byteOffset, encoding, true) } Buffer.prototype.lastIndexOf = function lastIndexOf (val, byteOffset, encoding) { return bidirectionalIndexOf(this, val, byteOffset, encoding, false) } function hexWrite (buf, string, offset, length) { offset = Number(offset) || 0 var remaining = buf.length - offset if (!length) { length = remaining } else { length = Number(length) if (length > remaining) { length = remaining } } // must be an even number of digits var strLen = string.length if (strLen % 2 !== 0) throw new TypeError('Invalid hex string') if (length > strLen / 2) { length = strLen / 2 } for (var i = 0; i < length; ++i) { var parsed = parseInt(string.substr(i * 2, 2), 16) if (isNaN(parsed)) return i buf[offset + i] = parsed } return i } function utf8Write (buf, string, offset, length) { return blitBuffer(utf8ToBytes(string, buf.length - offset), buf, offset, length) } function asciiWrite (buf, string, offset, length) { return blitBuffer(asciiToBytes(string), buf, offset, length) } function latin1Write (buf, string, offset, length) { return asciiWrite(buf, string, offset, length) } function base64Write (buf, string, offset, length) { return blitBuffer(base64ToBytes(string), buf, offset, length) } function ucs2Write (buf, string, offset, length) { return blitBuffer(utf16leToBytes(string, buf.length - offset), buf, offset, length) } Buffer.prototype.write = function write (string, offset, length, encoding) { // Buffer#write(string) if (offset === undefined) { encoding = 'utf8' length = this.length offset = 0 // Buffer#write(string, encoding) } else if (length === undefined && typeof offset === 'string') { encoding = offset length = this.length offset = 0 // Buffer#write(string, offset[, length][, encoding]) } else if (isFinite(offset)) { offset = offset | 0 if (isFinite(length)) { length = length | 0 if (encoding === undefined) encoding = 'utf8' } else { encoding = length length = undefined } // legacy write(string, encoding, offset, length) - remove in v0.13 } else { throw new Error( 'Buffer.write(string, encoding, offset[, length]) is no longer supported' ) } var remaining = this.length - offset if (length === undefined || length > remaining) length = remaining if ((string.length > 0 && (length < 0 || offset < 0)) || offset > this.length) { throw new RangeError('Attempt to write outside buffer bounds') } if (!encoding) encoding = 'utf8' var loweredCase = false for (;;) { switch (encoding) { case 'hex': return hexWrite(this, string, offset, length) case 'utf8': case 'utf-8': return utf8Write(this, string, offset, length) case 'ascii': return asciiWrite(this, string, offset, length) case 'latin1': case 'binary': return latin1Write(this, string, offset, length) case 'base64': // Warning: maxLength not taken into account in base64Write return base64Write(this, string, offset, length) case 'ucs2': case 'ucs-2': case 'utf16le': case 'utf-16le': return ucs2Write(this, string, offset, length) default: if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding) encoding = ('' + encoding).toLowerCase() loweredCase = true } } } Buffer.prototype.toJSON = function toJSON () { return { type: 'Buffer', data: Array.prototype.slice.call(this._arr || this, 0) } } function base64Slice (buf, start, end) { if (start === 0 && end === buf.length) { return base64.fromByteArray(buf) } else { return base64.fromByteArray(buf.slice(start, end)) } } function utf8Slice (buf, start, end) { end = Math.min(buf.length, end) var res = [] var i = start while (i < end) { var firstByte = buf[i] var codePoint = null var bytesPerSequence = (firstByte > 0xEF) ? 4 : (firstByte > 0xDF) ? 3 : (firstByte > 0xBF) ? 2 : 1 if (i + bytesPerSequence <= end) { var secondByte, thirdByte, fourthByte, tempCodePoint switch (bytesPerSequence) { case 1: if (firstByte < 0x80) { codePoint = firstByte } break case 2: secondByte = buf[i + 1] if ((secondByte & 0xC0) === 0x80) { tempCodePoint = (firstByte & 0x1F) << 0x6 | (secondByte & 0x3F) if (tempCodePoint > 0x7F) { codePoint = tempCodePoint } } break case 3: secondByte = buf[i + 1] thirdByte = buf[i + 2] if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80) { tempCodePoint = (firstByte & 0xF) << 0xC | (secondByte & 0x3F) << 0x6 | (thirdByte & 0x3F) if (tempCodePoint > 0x7FF && (tempCodePoint < 0xD800 || tempCodePoint > 0xDFFF)) { codePoint = tempCodePoint } } break case 4: secondByte = buf[i + 1] thirdByte = buf[i + 2] fourthByte = buf[i + 3] if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80 && (fourthByte & 0xC0) === 0x80) { tempCodePoint = (firstByte & 0xF) << 0x12 | (secondByte & 0x3F) << 0xC | (thirdByte & 0x3F) << 0x6 | (fourthByte & 0x3F) if (tempCodePoint > 0xFFFF && tempCodePoint < 0x110000) { codePoint = tempCodePoint } } } } if (codePoint === null) { // we did not generate a valid codePoint so insert a // replacement char (U+FFFD) and advance only 1 byte codePoint = 0xFFFD bytesPerSequence = 1 } else if (codePoint > 0xFFFF) { // encode to utf16 (surrogate pair dance) codePoint -= 0x10000 res.push(codePoint >>> 10 & 0x3FF | 0xD800) codePoint = 0xDC00 | codePoint & 0x3FF } res.push(codePoint) i += bytesPerSequence } return decodeCodePointsArray(res) } // Based on http://stackoverflow.com/a/22747272/680742, the browser with // the lowest limit is Chrome, with 0x10000 args. // We go 1 magnitude less, for safety var MAX_ARGUMENTS_LENGTH = 0x1000 function decodeCodePointsArray (codePoints) { var len = codePoints.length if (len <= MAX_ARGUMENTS_LENGTH) { return String.fromCharCode.apply(String, codePoints) // avoid extra slice() } // Decode in chunks to avoid "call stack size exceeded". var res = '' var i = 0 while (i < len) { res += String.fromCharCode.apply( String, codePoints.slice(i, i += MAX_ARGUMENTS_LENGTH) ) } return res } function asciiSlice (buf, start, end) { var ret = '' end = Math.min(buf.length, end) for (var i = start; i < end; ++i) { ret += String.fromCharCode(buf[i] & 0x7F) } return ret } function latin1Slice (buf, start, end) { var ret = '' end = Math.min(buf.length, end) for (var i = start; i < end; ++i) { ret += String.fromCharCode(buf[i]) } return ret } function hexSlice (buf, start, end) { var len = buf.length if (!start || start < 0) start = 0 if (!end || end < 0 || end > len) end = len var out = '' for (var i = start; i < end; ++i) { out += toHex(buf[i]) } return out } function utf16leSlice (buf, start, end) { var bytes = buf.slice(start, end) var res = '' for (var i = 0; i < bytes.length; i += 2) { res += String.fromCharCode(bytes[i] + bytes[i + 1] * 256) } return res } Buffer.prototype.slice = function slice (start, end) { var len = this.length start = ~~start end = end === undefined ? len : ~~end if (start < 0) { start += len if (start < 0) start = 0 } else if (start > len) { start = len } if (end < 0) { end += len if (end < 0) end = 0 } else if (end > len) { end = len } if (end < start) end = start var newBuf if (Buffer.TYPED_ARRAY_SUPPORT) { newBuf = this.subarray(start, end) newBuf.__proto__ = Buffer.prototype } else { var sliceLen = end - start newBuf = new Buffer(sliceLen, undefined) for (var i = 0; i < sliceLen; ++i) { newBuf[i] = this[i + start] } } return newBuf } /* * Need to make sure that buffer isn't trying to write out of bounds. */ function checkOffset (offset, ext, length) { if ((offset % 1) !== 0 || offset < 0) throw new RangeError('offset is not uint') if (offset + ext > length) throw new RangeError('Trying to access beyond buffer length') } Buffer.prototype.readUIntLE = function readUIntLE (offset, byteLength, noAssert) { offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) checkOffset(offset, byteLength, this.length) var val = this[offset] var mul = 1 var i = 0 while (++i < byteLength && (mul *= 0x100)) { val += this[offset + i] * mul } return val } Buffer.prototype.readUIntBE = function readUIntBE (offset, byteLength, noAssert) { offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) { checkOffset(offset, byteLength, this.length) } var val = this[offset + --byteLength] var mul = 1 while (byteLength > 0 && (mul *= 0x100)) { val += this[offset + --byteLength] * mul } return val } Buffer.prototype.readUInt8 = function readUInt8 (offset, noAssert) { if (!noAssert) checkOffset(offset, 1, this.length) return this[offset] } Buffer.prototype.readUInt16LE = function readUInt16LE (offset, noAssert) { if (!noAssert) checkOffset(offset, 2, this.length) return this[offset] | (this[offset + 1] << 8) } Buffer.prototype.readUInt16BE = function readUInt16BE (offset, noAssert) { if (!noAssert) checkOffset(offset, 2, this.length) return (this[offset] << 8) | this[offset + 1] } Buffer.prototype.readUInt32LE = function readUInt32LE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return ((this[offset]) | (this[offset + 1] << 8) | (this[offset + 2] << 16)) + (this[offset + 3] * 0x1000000) } Buffer.prototype.readUInt32BE = function readUInt32BE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return (this[offset] * 0x1000000) + ((this[offset + 1] << 16) | (this[offset + 2] << 8) | this[offset + 3]) } Buffer.prototype.readIntLE = function readIntLE (offset, byteLength, noAssert) { offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) checkOffset(offset, byteLength, this.length) var val = this[offset] var mul = 1 var i = 0 while (++i < byteLength && (mul *= 0x100)) { val += this[offset + i] * mul } mul *= 0x80 if (val >= mul) val -= Math.pow(2, 8 * byteLength) return val } Buffer.prototype.readIntBE = function readIntBE (offset, byteLength, noAssert) { offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) checkOffset(offset, byteLength, this.length) var i = byteLength var mul = 1 var val = this[offset + --i] while (i > 0 && (mul *= 0x100)) { val += this[offset + --i] * mul } mul *= 0x80 if (val >= mul) val -= Math.pow(2, 8 * byteLength) return val } Buffer.prototype.readInt8 = function readInt8 (offset, noAssert) { if (!noAssert) checkOffset(offset, 1, this.length) if (!(this[offset] & 0x80)) return (this[offset]) return ((0xff - this[offset] + 1) * -1) } Buffer.prototype.readInt16LE = function readInt16LE (offset, noAssert) { if (!noAssert) checkOffset(offset, 2, this.length) var val = this[offset] | (this[offset + 1] << 8) return (val & 0x8000) ? val | 0xFFFF0000 : val } Buffer.prototype.readInt16BE = function readInt16BE (offset, noAssert) { if (!noAssert) checkOffset(offset, 2, this.length) var val = this[offset + 1] | (this[offset] << 8) return (val & 0x8000) ? val | 0xFFFF0000 : val } Buffer.prototype.readInt32LE = function readInt32LE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return (this[offset]) | (this[offset + 1] << 8) | (this[offset + 2] << 16) | (this[offset + 3] << 24) } Buffer.prototype.readInt32BE = function readInt32BE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return (this[offset] << 24) | (this[offset + 1] << 16) | (this[offset + 2] << 8) | (this[offset + 3]) } Buffer.prototype.readFloatLE = function readFloatLE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return ieee754.read(this, offset, true, 23, 4) } Buffer.prototype.readFloatBE = function readFloatBE (offset, noAssert) { if (!noAssert) checkOffset(offset, 4, this.length) return ieee754.read(this, offset, false, 23, 4) } Buffer.prototype.readDoubleLE = function readDoubleLE (offset, noAssert) { if (!noAssert) checkOffset(offset, 8, this.length) return ieee754.read(this, offset, true, 52, 8) } Buffer.prototype.readDoubleBE = function readDoubleBE (offset, noAssert) { if (!noAssert) checkOffset(offset, 8, this.length) return ieee754.read(this, offset, false, 52, 8) } function checkInt (buf, value, offset, ext, max, min) { if (!Buffer.isBuffer(buf)) throw new TypeError('"buffer" argument must be a Buffer instance') if (value > max || value < min) throw new RangeError('"value" argument is out of bounds') if (offset + ext > buf.length) throw new RangeError('Index out of range') } Buffer.prototype.writeUIntLE = function writeUIntLE (value, offset, byteLength, noAssert) { value = +value offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) { var maxBytes = Math.pow(2, 8 * byteLength) - 1 checkInt(this, value, offset, byteLength, maxBytes, 0) } var mul = 1 var i = 0 this[offset] = value & 0xFF while (++i < byteLength && (mul *= 0x100)) { this[offset + i] = (value / mul) & 0xFF } return offset + byteLength } Buffer.prototype.writeUIntBE = function writeUIntBE (value, offset, byteLength, noAssert) { value = +value offset = offset | 0 byteLength = byteLength | 0 if (!noAssert) { var maxBytes = Math.pow(2, 8 * byteLength) - 1 checkInt(this, value, offset, byteLength, maxBytes, 0) } var i = byteLength - 1 var mul = 1 this[offset + i] = value & 0xFF while (--i >= 0 && (mul *= 0x100)) { this[offset + i] = (value / mul) & 0xFF } return offset + byteLength } Buffer.prototype.writeUInt8 = function writeUInt8 (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 1, 0xff, 0) if (!Buffer.TYPED_ARRAY_SUPPORT) value = Math.floor(value) this[offset] = (value & 0xff) return offset + 1 } function objectWriteUInt16 (buf, value, offset, littleEndian) { if (value < 0) value = 0xffff + value + 1 for (var i = 0, j = Math.min(buf.length - offset, 2); i < j; ++i) { buf[offset + i] = (value & (0xff << (8 * (littleEndian ? i : 1 - i)))) >>> (littleEndian ? i : 1 - i) * 8 } } Buffer.prototype.writeUInt16LE = function writeUInt16LE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value & 0xff) this[offset + 1] = (value >>> 8) } else { objectWriteUInt16(this, value, offset, true) } return offset + 2 } Buffer.prototype.writeUInt16BE = function writeUInt16BE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value >>> 8) this[offset + 1] = (value & 0xff) } else { objectWriteUInt16(this, value, offset, false) } return offset + 2 } function objectWriteUInt32 (buf, value, offset, littleEndian) { if (value < 0) value = 0xffffffff + value + 1 for (var i = 0, j = Math.min(buf.length - offset, 4); i < j; ++i) { buf[offset + i] = (value >>> (littleEndian ? i : 3 - i) * 8) & 0xff } } Buffer.prototype.writeUInt32LE = function writeUInt32LE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset + 3] = (value >>> 24) this[offset + 2] = (value >>> 16) this[offset + 1] = (value >>> 8) this[offset] = (value & 0xff) } else { objectWriteUInt32(this, value, offset, true) } return offset + 4 } Buffer.prototype.writeUInt32BE = function writeUInt32BE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value >>> 24) this[offset + 1] = (value >>> 16) this[offset + 2] = (value >>> 8) this[offset + 3] = (value & 0xff) } else { objectWriteUInt32(this, value, offset, false) } return offset + 4 } Buffer.prototype.writeIntLE = function writeIntLE (value, offset, byteLength, noAssert) { value = +value offset = offset | 0 if (!noAssert) { var limit = Math.pow(2, 8 * byteLength - 1) checkInt(this, value, offset, byteLength, limit - 1, -limit) } var i = 0 var mul = 1 var sub = 0 this[offset] = value & 0xFF while (++i < byteLength && (mul *= 0x100)) { if (value < 0 && sub === 0 && this[offset + i - 1] !== 0) { sub = 1 } this[offset + i] = ((value / mul) >> 0) - sub & 0xFF } return offset + byteLength } Buffer.prototype.writeIntBE = function writeIntBE (value, offset, byteLength, noAssert) { value = +value offset = offset | 0 if (!noAssert) { var limit = Math.pow(2, 8 * byteLength - 1) checkInt(this, value, offset, byteLength, limit - 1, -limit) } var i = byteLength - 1 var mul = 1 var sub = 0 this[offset + i] = value & 0xFF while (--i >= 0 && (mul *= 0x100)) { if (value < 0 && sub === 0 && this[offset + i + 1] !== 0) { sub = 1 } this[offset + i] = ((value / mul) >> 0) - sub & 0xFF } return offset + byteLength } Buffer.prototype.writeInt8 = function writeInt8 (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 1, 0x7f, -0x80) if (!Buffer.TYPED_ARRAY_SUPPORT) value = Math.floor(value) if (value < 0) value = 0xff + value + 1 this[offset] = (value & 0xff) return offset + 1 } Buffer.prototype.writeInt16LE = function writeInt16LE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value & 0xff) this[offset + 1] = (value >>> 8) } else { objectWriteUInt16(this, value, offset, true) } return offset + 2 } Buffer.prototype.writeInt16BE = function writeInt16BE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value >>> 8) this[offset + 1] = (value & 0xff) } else { objectWriteUInt16(this, value, offset, false) } return offset + 2 } Buffer.prototype.writeInt32LE = function writeInt32LE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000) if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value & 0xff) this[offset + 1] = (value >>> 8) this[offset + 2] = (value >>> 16) this[offset + 3] = (value >>> 24) } else { objectWriteUInt32(this, value, offset, true) } return offset + 4 } Buffer.prototype.writeInt32BE = function writeInt32BE (value, offset, noAssert) { value = +value offset = offset | 0 if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000) if (value < 0) value = 0xffffffff + value + 1 if (Buffer.TYPED_ARRAY_SUPPORT) { this[offset] = (value >>> 24) this[offset + 1] = (value >>> 16) this[offset + 2] = (value >>> 8) this[offset + 3] = (value & 0xff) } else { objectWriteUInt32(this, value, offset, false) } return offset + 4 } function checkIEEE754 (buf, value, offset, ext, max, min) { if (offset + ext > buf.length) throw new RangeError('Index out of range') if (offset < 0) throw new RangeError('Index out of range') } function writeFloat (buf, value, offset, littleEndian, noAssert) { if (!noAssert) { checkIEEE754(buf, value, offset, 4, 3.4028234663852886e+38, -3.4028234663852886e+38) } ieee754.write(buf, value, offset, littleEndian, 23, 4) return offset + 4 } Buffer.prototype.writeFloatLE = function writeFloatLE (value, offset, noAssert) { return writeFloat(this, value, offset, true, noAssert) } Buffer.prototype.writeFloatBE = function writeFloatBE (value, offset, noAssert) { return writeFloat(this, value, offset, false, noAssert) } function writeDouble (buf, value, offset, littleEndian, noAssert) { if (!noAssert) { checkIEEE754(buf, value, offset, 8, 1.7976931348623157E+308, -1.7976931348623157E+308) } ieee754.write(buf, value, offset, littleEndian, 52, 8) return offset + 8 } Buffer.prototype.writeDoubleLE = function writeDoubleLE (value, offset, noAssert) { return writeDouble(this, value, offset, true, noAssert) } Buffer.prototype.writeDoubleBE = function writeDoubleBE (value, offset, noAssert) { return writeDouble(this, value, offset, false, noAssert) } // copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length) Buffer.prototype.copy = function copy (target, targetStart, start, end) { if (!start) start = 0 if (!end && end !== 0) end = this.length if (targetStart >= target.length) targetStart = target.length if (!targetStart) targetStart = 0 if (end > 0 && end < start) end = start // Copy 0 bytes; we're done if (end === start) return 0 if (target.length === 0 || this.length === 0) return 0 // Fatal error conditions if (targetStart < 0) { throw new RangeError('targetStart out of bounds') } if (start < 0 || start >= this.length) throw new RangeError('sourceStart out of bounds') if (end < 0) throw new RangeError('sourceEnd out of bounds') // Are we oob? if (end > this.length) end = this.length if (target.length - targetStart < end - start) { end = target.length - targetStart + start } var len = end - start var i if (this === target && start < targetStart && targetStart < end) { // descending copy from end for (i = len - 1; i >= 0; --i) { target[i + targetStart] = this[i + start] } } else if (len < 1000 || !Buffer.TYPED_ARRAY_SUPPORT) { // ascending copy from start for (i = 0; i < len; ++i) { target[i + targetStart] = this[i + start] } } else { Uint8Array.prototype.set.call( target, this.subarray(start, start + len), targetStart ) } return len } // Usage: // buffer.fill(number[, offset[, end]]) // buffer.fill(buffer[, offset[, end]]) // buffer.fill(string[, offset[, end]][, encoding]) Buffer.prototype.fill = function fill (val, start, end, encoding) { // Handle string cases: if (typeof val === 'string') { if (typeof start === 'string') { encoding = start start = 0 end = this.length } else if (typeof end === 'string') { encoding = end end = this.length } if (val.length === 1) { var code = val.charCodeAt(0) if (code < 256) { val = code } } if (encoding !== undefined && typeof encoding !== 'string') { throw new TypeError('encoding must be a string') } if (typeof encoding === 'string' && !Buffer.isEncoding(encoding)) { throw new TypeError('Unknown encoding: ' + encoding) } } else if (typeof val === 'number') { val = val & 255 } // Invalid ranges are not set to a default, so can range check early. if (start < 0 || this.length < start || this.length < end) { throw new RangeError('Out of range index') } if (end <= start) { return this } start = start >>> 0 end = end === undefined ? this.length : end >>> 0 if (!val) val = 0 var i if (typeof val === 'number') { for (i = start; i < end; ++i) { this[i] = val } } else { var bytes = Buffer.isBuffer(val) ? val : utf8ToBytes(new Buffer(val, encoding).toString()) var len = bytes.length for (i = 0; i < end - start; ++i) { this[i + start] = bytes[i % len] } } return this } // HELPER FUNCTIONS // ================ var INVALID_BASE64_RE = /[^+\/0-9A-Za-z-_]/g function base64clean (str) { // Node strips out invalid characters like \n and \t from the string, base64-js does not str = stringtrim(str).replace(INVALID_BASE64_RE, '') // Node converts strings with length < 2 to '' if (str.length < 2) return '' // Node allows for non-padded base64 strings (missing trailing ===), base64-js does not while (str.length % 4 !== 0) { str = str + '=' } return str } function stringtrim (str) { if (str.trim) return str.trim() return str.replace(/^\s+|\s+$/g, '') } function toHex (n) { if (n < 16) return '0' + n.toString(16) return n.toString(16) } function utf8ToBytes (string, units) { units = units || Infinity var codePoint var length = string.length var leadSurrogate = null var bytes = [] for (var i = 0; i < length; ++i) { codePoint = string.charCodeAt(i) // is surrogate component if (codePoint > 0xD7FF && codePoint < 0xE000) { // last char was a lead if (!leadSurrogate) { // no lead yet if (codePoint > 0xDBFF) { // unexpected trail if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD) continue } else if (i + 1 === length) { // unpaired lead if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD) continue } // valid lead leadSurrogate = codePoint continue } // 2 leads in a row if (codePoint < 0xDC00) { if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD) leadSurrogate = codePoint continue } // valid surrogate pair codePoint = (leadSurrogate - 0xD800 << 10 | codePoint - 0xDC00) + 0x10000 } else if (leadSurrogate) { // valid bmp char, but last char was a lead if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD) } leadSurrogate = null // encode utf8 if (codePoint < 0x80) { if ((units -= 1) < 0) break bytes.push(codePoint) } else if (codePoint < 0x800) { if ((units -= 2) < 0) break bytes.push( codePoint >> 0x6 | 0xC0, codePoint & 0x3F | 0x80 ) } else if (codePoint < 0x10000) { if ((units -= 3) < 0) break bytes.push( codePoint >> 0xC | 0xE0, codePoint >> 0x6 & 0x3F | 0x80, codePoint & 0x3F | 0x80 ) } else if (codePoint < 0x110000) { if ((units -= 4) < 0) break bytes.push( codePoint >> 0x12 | 0xF0, codePoint >> 0xC & 0x3F | 0x80, codePoint >> 0x6 & 0x3F | 0x80, codePoint & 0x3F | 0x80 ) } else { throw new Error('Invalid code point') } } return bytes } function asciiToBytes (str) { var byteArray = [] for (var i = 0; i < str.length; ++i) { // Node's code seems to be doing this and not & 0x7F.. byteArray.push(str.charCodeAt(i) & 0xFF) } return byteArray } function utf16leToBytes (str, units) { var c, hi, lo var byteArray = [] for (var i = 0; i < str.length; ++i) { if ((units -= 2) < 0) break c = str.charCodeAt(i) hi = c >> 8 lo = c % 256 byteArray.push(lo) byteArray.push(hi) } return byteArray } function base64ToBytes (str) { return base64.toByteArray(base64clean(str)) } function blitBuffer (src, dst, offset, length) { for (var i = 0; i < length; ++i) { if ((i + offset >= dst.length) || (i >= src.length)) break dst[i + offset] = src[i] } return i } function isnan (val) { return val !== val // eslint-disable-line no-self-compare }