pouchdb-replication-stream
Version:
PouchDB/CouchDB replication as a stream
1,773 lines (1,529 loc) • 299 kB
JavaScript
(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.PouchReplicationStream = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(_dereq_,module,exports){
(function (process){
'use strict';
var Promise = _dereq_(26);
/* istanbul ignore next */
exports.once = function (fun) {
var called = false;
return exports.getArguments(function (args) {
if (called) {
console.trace();
throw new Error('once called more than once');
} else {
called = true;
fun.apply(this, args);
}
});
};
/* istanbul ignore next */
exports.getArguments = function (fun) {
return function () {
var len = arguments.length;
var args = new Array(len);
var i = -1;
while (++i < len) {
args[i] = arguments[i];
}
return fun.call(this, args);
};
};
/* istanbul ignore next */
exports.toPromise = function (func) {
//create the function we will be returning
return exports.getArguments(function (args) {
var self = this;
var tempCB = (typeof args[args.length - 1] === 'function') ? args.pop() : false;
// if the last argument is a function, assume its a callback
var usedCB;
if (tempCB) {
// if it was a callback, create a new callback which calls it,
// but do so async so we don't trap any errors
usedCB = function (err, resp) {
process.nextTick(function () {
tempCB(err, resp);
});
};
}
var promise = new Promise(function (fulfill, reject) {
try {
var callback = exports.once(function (err, mesg) {
if (err) {
reject(err);
} else {
fulfill(mesg);
}
});
// create a callback for this invocation
// apply the function in the orig context
args.push(callback);
func.apply(self, args);
} catch (e) {
reject(e);
}
});
// if there is a callback, call it back
if (usedCB) {
promise.then(function (result) {
usedCB(null, result);
}, usedCB);
}
promise.cancel = function () {
return this;
};
return promise;
});
};
exports.inherits = _dereq_(14);
}).call(this,_dereq_(28))
},{"14":14,"26":26,"28":28}],2:[function(_dereq_,module,exports){
(function (Buffer){
'use strict';
var through = _dereq_(58).obj;
module.exports = function () {
return through(function (chunk, _, next) {
// this only applies in the browser
/* istanbul ignore next */
if (!(chunk instanceof Buffer) && Buffer.isBuffer(chunk)) {
chunk = new Buffer(chunk);
}
this.push(chunk);
next();
});
};
}).call(this,_dereq_(8).Buffer)
},{"58":58,"8":8}],3:[function(_dereq_,module,exports){
'use strict';
module.exports = _dereq_(64).version;
},{"64":64}],4:[function(_dereq_,module,exports){
(function (process){
'use strict';
var utils = _dereq_(1);
var Promise = _dereq_(26);
var ERROR_REV_CONFLICT = {
status: 409,
name: 'conflict',
message: 'Document update conflict'
};
var ndj = _dereq_(19);
var ERROR_MISSING_DOC = {
status: 404,
name: 'not_found',
message: 'missing'
};
function WritableStreamPouch(opts, callback) {
var api = this;
api.instanceId = Math.random().toString();
api.ndj = ndj.serialize();
api.localStore = {};
api.originalName = opts.name;
// TODO: I would pass this in as a constructor opt, but
// PouchDB changed how it clones in 5.0.0 so this broke
api.setupStream = function (stream) {
api.ndj.pipe(stream);
};
/* istanbul ignore next */
api.type = function () {
return 'writableStream';
};
api._id = utils.toPromise(function (callback) {
callback(null, api.instanceId);
});
api._bulkDocs = function (req, opts, callback) {
var docs = req.docs;
var self = this;
/* istanbul ignore else */
if (opts.new_edits === false) {
// assume we're only getting this with new_edits=false,
// since this adapter is just a replication target
this.ndj.write({docs: docs}, function () {
callback(null, docs.map(function (doc) {
return {
ok: true,
id: doc._id,
rev: doc._rev
};
}));
});
} else {
// writing local docs for replication
Promise.all(docs.map(function (doc) {
self.localStore[doc._id] = doc;
})).then(function (res) {
callback(null, res);
})["catch"](function (err) {
callback(err);
});
}
};
api._getRevisionTree = function (docId, callback) {
process.nextTick(function () {
callback(ERROR_MISSING_DOC);
});
};
api._close = function (callback) {
this.ndj.end(callback);
};
api._getLocal = function (id, callback) {
var self = this;
process.nextTick(function () {
var existingDoc = self.localStore[id];
/* istanbul ignore else */
if (existingDoc) {
callback(null, existingDoc);
} else {
callback(ERROR_MISSING_DOC);
}
});
};
api._putLocal = function (doc, opts, callback) {
var self = this;
/* istanbul ignore else */
if (typeof opts === 'function') {
callback = opts;
opts = {};
}
delete doc._revisions; // ignore this, trust the rev
var oldRev = doc._rev;
var id = doc._id;
var newRev;
if (!oldRev) {
newRev = doc._rev = '0-1';
} else {
newRev = doc._rev = '0-' + (parseInt(oldRev.split('-')[1], 10) + 1);
}
process.nextTick(function () {
var existingDoc = self.localStore[id];
/* istanbul ignore if */
if (existingDoc && oldRev !== existingDoc._rev) {
callback(ERROR_REV_CONFLICT);
} else {
self.localStore[id] = doc;
var done = function () {
callback(null, {ok: true, id: id, rev: newRev});
};
/* istanbul ignore else */
if ('last_seq' in doc) {
self.ndj.write({seq: doc.last_seq}, done);
} else {
done();
}
}
});
};
/* istanbul ignore next */
api._removeLocal = function (doc, callback) {
var self = this;
process.nextTick(function () {
var existingDoc = self.localStore[doc._id];
if (existingDoc && doc._rev !== existingDoc._rev) {
callback(ERROR_REV_CONFLICT);
} else {
delete self.localStore[doc._id];
callback(null, {ok: true, id: doc._id, rev: '0-0'});
}
});
};
/* istanbul ignore next */
api._destroy = function (opts, callback) {
if (typeof opts === 'function') {
callback = opts;
opts = {};
}
WritableStreamPouch.Changes.removeAllListeners(api.originalName);
process.nextTick(function () {
callback(null, {'ok': true});
});
};
process.nextTick(function () {
callback(null, api);
});
}
WritableStreamPouch.valid = function () {
return true;
};
module.exports = WritableStreamPouch;
}).call(this,_dereq_(28))
},{"1":1,"19":19,"26":26,"28":28}],5:[function(_dereq_,module,exports){
var lookup = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
;(function (exports) {
'use strict';
var Arr = (typeof Uint8Array !== 'undefined')
? Uint8Array
: Array
var PLUS = '+'.charCodeAt(0)
var SLASH = '/'.charCodeAt(0)
var NUMBER = '0'.charCodeAt(0)
var LOWER = 'a'.charCodeAt(0)
var UPPER = 'A'.charCodeAt(0)
var PLUS_URL_SAFE = '-'.charCodeAt(0)
var SLASH_URL_SAFE = '_'.charCodeAt(0)
function decode (elt) {
var code = elt.charCodeAt(0)
if (code === PLUS ||
code === PLUS_URL_SAFE)
return 62 // '+'
if (code === SLASH ||
code === SLASH_URL_SAFE)
return 63 // '/'
if (code < NUMBER)
return -1 //no match
if (code < NUMBER + 10)
return code - NUMBER + 26 + 26
if (code < UPPER + 26)
return code - UPPER
if (code < LOWER + 26)
return code - LOWER + 26
}
function b64ToByteArray (b64) {
var i, j, l, tmp, placeHolders, arr
if (b64.length % 4 > 0) {
throw new Error('Invalid string. Length must be a multiple of 4')
}
// the number of equal signs (place holders)
// if there are two placeholders, than the two characters before it
// represent one byte
// if there is only one, then the three characters before it represent 2 bytes
// this is just a cheap hack to not do indexOf twice
var len = b64.length
placeHolders = '=' === b64.charAt(len - 2) ? 2 : '=' === b64.charAt(len - 1) ? 1 : 0
// base64 is 4/3 + up to two characters of the original data
arr = new Arr(b64.length * 3 / 4 - placeHolders)
// if there are placeholders, only get up to the last complete 4 chars
l = placeHolders > 0 ? b64.length - 4 : b64.length
var L = 0
function push (v) {
arr[L++] = v
}
for (i = 0, j = 0; i < l; i += 4, j += 3) {
tmp = (decode(b64.charAt(i)) << 18) | (decode(b64.charAt(i + 1)) << 12) | (decode(b64.charAt(i + 2)) << 6) | decode(b64.charAt(i + 3))
push((tmp & 0xFF0000) >> 16)
push((tmp & 0xFF00) >> 8)
push(tmp & 0xFF)
}
if (placeHolders === 2) {
tmp = (decode(b64.charAt(i)) << 2) | (decode(b64.charAt(i + 1)) >> 4)
push(tmp & 0xFF)
} else if (placeHolders === 1) {
tmp = (decode(b64.charAt(i)) << 10) | (decode(b64.charAt(i + 1)) << 4) | (decode(b64.charAt(i + 2)) >> 2)
push((tmp >> 8) & 0xFF)
push(tmp & 0xFF)
}
return arr
}
function uint8ToBase64 (uint8) {
var i,
extraBytes = uint8.length % 3, // if we have 1 byte left, pad 2 bytes
output = "",
temp, length
function encode (num) {
return lookup.charAt(num)
}
function tripletToBase64 (num) {
return encode(num >> 18 & 0x3F) + encode(num >> 12 & 0x3F) + encode(num >> 6 & 0x3F) + encode(num & 0x3F)
}
// go through the array every three bytes, we'll deal with trailing stuff later
for (i = 0, length = uint8.length - extraBytes; i < length; i += 3) {
temp = (uint8[i] << 16) + (uint8[i + 1] << 8) + (uint8[i + 2])
output += tripletToBase64(temp)
}
// pad the end with zeros, but make sure to not forget the extra bytes
switch (extraBytes) {
case 1:
temp = uint8[uint8.length - 1]
output += encode(temp >> 2)
output += encode((temp << 4) & 0x3F)
output += '=='
break
case 2:
temp = (uint8[uint8.length - 2] << 8) + (uint8[uint8.length - 1])
output += encode(temp >> 10)
output += encode((temp >> 4) & 0x3F)
output += encode((temp << 2) & 0x3F)
output += '='
break
}
return output
}
exports.toByteArray = b64ToByteArray
exports.fromByteArray = uint8ToBase64
}(typeof exports === 'undefined' ? (this.base64js = {}) : exports))
},{}],6:[function(_dereq_,module,exports){
},{}],7:[function(_dereq_,module,exports){
(function (global){
'use strict';
var buffer = _dereq_(8);
var Buffer = buffer.Buffer;
var SlowBuffer = buffer.SlowBuffer;
var MAX_LEN = buffer.kMaxLength || 2147483647;
exports.alloc = function alloc(size, fill, encoding) {
if (typeof Buffer.alloc === 'function') {
return Buffer.alloc(size, fill, encoding);
}
if (typeof encoding === 'number') {
throw new TypeError('encoding must not be number');
}
if (typeof size !== 'number') {
throw new TypeError('size must be a number');
}
if (size > MAX_LEN) {
throw new RangeError('size is too large');
}
var enc = encoding;
var _fill = fill;
if (_fill === undefined) {
enc = undefined;
_fill = 0;
}
var buf = new Buffer(size);
if (typeof _fill === 'string') {
var fillBuf = new Buffer(_fill, enc);
var flen = fillBuf.length;
var i = -1;
while (++i < size) {
buf[i] = fillBuf[i % flen];
}
} else {
buf.fill(_fill);
}
return buf;
}
exports.allocUnsafe = function allocUnsafe(size) {
if (typeof Buffer.allocUnsafe === 'function') {
return Buffer.allocUnsafe(size);
}
if (typeof size !== 'number') {
throw new TypeError('size must be a number');
}
if (size > MAX_LEN) {
throw new RangeError('size is too large');
}
return new Buffer(size);
}
exports.from = function from(value, encodingOrOffset, length) {
if (typeof Buffer.from === 'function' && (!global.Uint8Array || Uint8Array.from !== Buffer.from)) {
return Buffer.from(value, encodingOrOffset, length);
}
if (typeof value === 'number') {
throw new TypeError('"value" argument must not be a number');
}
if (typeof value === 'string') {
return new Buffer(value, encodingOrOffset);
}
if (typeof ArrayBuffer !== 'undefined' && value instanceof ArrayBuffer) {
var offset = encodingOrOffset;
if (arguments.length === 1) {
return new Buffer(value);
}
if (typeof offset === 'undefined') {
offset = 0;
}
var len = length;
if (typeof len === 'undefined') {
len = value.byteLength - offset;
}
if (offset >= value.byteLength) {
throw new RangeError('\'offset\' is out of bounds');
}
if (len > value.byteLength - offset) {
throw new RangeError('\'length\' is out of bounds');
}
return new Buffer(value.slice(offset, offset + len));
}
if (Buffer.isBuffer(value)) {
var out = new Buffer(value.length);
value.copy(out, 0, 0, value.length);
return out;
}
if (value) {
if (Array.isArray(value) || (typeof ArrayBuffer !== 'undefined' && value.buffer instanceof ArrayBuffer) || 'length' in value) {
return new Buffer(value);
}
if (value.type === 'Buffer' && Array.isArray(value.data)) {
return new Buffer(value.data);
}
}
throw new TypeError('First argument must be a string, Buffer, ' + 'ArrayBuffer, Array, or array-like object.');
}
exports.allocUnsafeSlow = function allocUnsafeSlow(size) {
if (typeof Buffer.allocUnsafeSlow === 'function') {
return Buffer.allocUnsafeSlow(size);
}
if (typeof size !== 'number') {
throw new TypeError('size must be a number');
}
if (size >= MAX_LEN) {
throw new RangeError('size is too large');
}
return new SlowBuffer(size);
}
}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"8":8}],8:[function(_dereq_,module,exports){
(function (global){
/*!
* The buffer module from node.js, for the browser.
*
* @author Feross Aboukhadijeh <feross@feross.org> <http://feross.org>
* @license MIT
*/
/* eslint-disable no-proto */
'use strict'
var base64 = _dereq_(5)
var ieee754 = _dereq_(12)
var isArray = _dereq_(9)
exports.Buffer = Buffer
exports.SlowBuffer = SlowBuffer
exports.INSPECT_MAX_BYTES = 50
Buffer.poolSize = 8192 // not used by this implementation
var rootParent = {}
/**
* 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.
*
* - Safari 5-7 lacks support for changing the `Object.prototype.constructor` property
* on objects.
*
* - 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()
function typedArraySupport () {
function Bar () {}
try {
var arr = new Uint8Array(1)
arr.foo = function () { return 42 }
arr.constructor = Bar
return arr.foo() === 42 && // typed array instances can be augmented
arr.constructor === Bar && // constructor can be set
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
}
/**
* Class: Buffer
* =============
*
* The Buffer constructor returns instances of `Uint8Array` that are augmented
* with function properties for all the node `Buffer` API functions. We use
* `Uint8Array` so that square bracket notation works as expected -- it returns
* a single octet.
*
* By augmenting the instances, we can avoid modifying the `Uint8Array`
* prototype.
*/
function Buffer (arg) {
if (!(this instanceof Buffer)) {
// Avoid going through an ArgumentsAdaptorTrampoline in the common case.
if (arguments.length > 1) return new Buffer(arg, arguments[1])
return new Buffer(arg)
}
if (!Buffer.TYPED_ARRAY_SUPPORT) {
this.length = 0
this.parent = undefined
}
// Common case.
if (typeof arg === 'number') {
return fromNumber(this, arg)
}
// Slightly less common case.
if (typeof arg === 'string') {
return fromString(this, arg, arguments.length > 1 ? arguments[1] : 'utf8')
}
// Unusual.
return fromObject(this, arg)
}
function fromNumber (that, length) {
that = allocate(that, length < 0 ? 0 : checked(length) | 0)
if (!Buffer.TYPED_ARRAY_SUPPORT) {
for (var i = 0; i < length; i++) {
that[i] = 0
}
}
return that
}
function fromString (that, string, encoding) {
if (typeof encoding !== 'string' || encoding === '') encoding = 'utf8'
// Assumption: byteLength() return value is always < kMaxLength.
var length = byteLength(string, encoding) | 0
that = allocate(that, length)
that.write(string, encoding)
return that
}
function fromObject (that, object) {
if (Buffer.isBuffer(object)) return fromBuffer(that, object)
if (isArray(object)) return fromArray(that, object)
if (object == null) {
throw new TypeError('must start with number, buffer, array or string')
}
if (typeof ArrayBuffer !== 'undefined') {
if (object.buffer instanceof ArrayBuffer) {
return fromTypedArray(that, object)
}
if (object instanceof ArrayBuffer) {
return fromArrayBuffer(that, object)
}
}
if (object.length) return fromArrayLike(that, object)
return fromJsonObject(that, object)
}
function fromBuffer (that, buffer) {
var length = checked(buffer.length) | 0
that = allocate(that, length)
buffer.copy(that, 0, 0, length)
return that
}
function fromArray (that, array) {
var length = checked(array.length) | 0
that = allocate(that, length)
for (var i = 0; i < length; i += 1) {
that[i] = array[i] & 255
}
return that
}
// Duplicate of fromArray() to keep fromArray() monomorphic.
function fromTypedArray (that, array) {
var length = checked(array.length) | 0
that = allocate(that, length)
// Truncating the elements is probably not what people expect from typed
// arrays with BYTES_PER_ELEMENT > 1 but it's compatible with the behavior
// of the old Buffer constructor.
for (var i = 0; i < length; i += 1) {
that[i] = array[i] & 255
}
return that
}
function fromArrayBuffer (that, array) {
if (Buffer.TYPED_ARRAY_SUPPORT) {
// Return an augmented `Uint8Array` instance, for best performance
array.byteLength
that = Buffer._augment(new Uint8Array(array))
} else {
// Fallback: Return an object instance of the Buffer class
that = fromTypedArray(that, new Uint8Array(array))
}
return that
}
function fromArrayLike (that, array) {
var length = checked(array.length) | 0
that = allocate(that, length)
for (var i = 0; i < length; i += 1) {
that[i] = array[i] & 255
}
return that
}
// Deserialize { type: 'Buffer', data: [1,2,3,...] } into a Buffer object.
// Returns a zero-length buffer for inputs that don't conform to the spec.
function fromJsonObject (that, object) {
var array
var length = 0
if (object.type === 'Buffer' && isArray(object.data)) {
array = object.data
length = checked(array.length) | 0
}
that = allocate(that, length)
for (var i = 0; i < length; i += 1) {
that[i] = array[i] & 255
}
return that
}
if (Buffer.TYPED_ARRAY_SUPPORT) {
Buffer.prototype.__proto__ = Uint8Array.prototype
Buffer.__proto__ = Uint8Array
} else {
// pre-set for values that may exist in the future
Buffer.prototype.length = undefined
Buffer.prototype.parent = undefined
}
function allocate (that, length) {
if (Buffer.TYPED_ARRAY_SUPPORT) {
// Return an augmented `Uint8Array` instance, for best performance
that = Buffer._augment(new Uint8Array(length))
that.__proto__ = Buffer.prototype
} else {
// Fallback: Return an object instance of the Buffer class
that.length = length
that._isBuffer = true
}
var fromPool = length !== 0 && length <= Buffer.poolSize >>> 1
if (fromPool) that.parent = rootParent
return that
}
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 (subject, encoding) {
if (!(this instanceof SlowBuffer)) return new SlowBuffer(subject, encoding)
var buf = new Buffer(subject, encoding)
delete buf.parent
return buf
}
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
var i = 0
var len = Math.min(x, y)
while (i < len) {
if (a[i] !== b[i]) break
++i
}
if (i !== len) {
x = a[i]
y = b[i]
}
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 'binary':
case 'base64':
case 'raw':
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 new Buffer(0)
}
var i
if (length === undefined) {
length = 0
for (i = 0; i < list.length; i++) {
length += list[i].length
}
}
var buf = new Buffer(length)
var pos = 0
for (i = 0; i < list.length; i++) {
var item = list[i]
item.copy(buf, pos)
pos += item.length
}
return buf
}
function byteLength (string, encoding) {
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 'binary':
// Deprecated
case 'raw':
case 'raws':
return len
case 'utf8':
case 'utf-8':
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
start = start | 0
end = end === undefined || end === Infinity ? this.length : end | 0
if (!encoding) encoding = 'utf8'
if (start < 0) start = 0
if (end > this.length) end = this.length
if (end <= start) return ''
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 'binary':
return binarySlice(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
}
}
}
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 ' + str + '>'
}
Buffer.prototype.compare = function compare (b) {
if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
if (this === b) return 0
return Buffer.compare(this, b)
}
Buffer.prototype.indexOf = function indexOf (val, byteOffset) {
if (byteOffset > 0x7fffffff) byteOffset = 0x7fffffff
else if (byteOffset < -0x80000000) byteOffset = -0x80000000
byteOffset >>= 0
if (this.length === 0) return -1
if (byteOffset >= this.length) return -1
// Negative offsets start from the end of the buffer
if (byteOffset < 0) byteOffset = Math.max(this.length + byteOffset, 0)
if (typeof val === 'string') {
if (val.length === 0) return -1 // special case: looking for empty string always fails
return String.prototype.indexOf.call(this, val, byteOffset)
}
if (Buffer.isBuffer(val)) {
return arrayIndexOf(this, val, byteOffset)
}
if (typeof val === 'number') {
if (Buffer.TYPED_ARRAY_SUPPORT && Uint8Array.prototype.indexOf === 'function') {
return Uint8Array.prototype.indexOf.call(this, val, byteOffset)
}
return arrayIndexOf(this, [ val ], byteOffset)
}
function arrayIndexOf (arr, val, byteOffset) {
var foundIndex = -1
for (var i = 0; byteOffset + i < arr.length; i++) {
if (arr[byteOffset + i] === val[foundIndex === -1 ? 0 : i - foundIndex]) {
if (foundIndex === -1) foundIndex = i
if (i - foundIndex + 1 === val.length) return byteOffset + foundIndex
} else {
foundIndex = -1
}
}
return -1
}
throw new TypeError('val must be string, number or Buffer')
}
// `get` is deprecated
Buffer.prototype.get = function get (offset) {
console.log('.get() is deprecated. Access using array indexes instead.')
return this.readUInt8(offset)
}
// `set` is deprecated
Buffer.prototype.set = function set (v, offset) {
console.log('.set() is deprecated. Access using array indexes instead.')
return this.writeUInt8(v, offset)
}
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 Error('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)) throw new Error('Invalid hex string')
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 binaryWrite (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 {
var swap = encoding
encoding = offset
offset = length | 0
length = swap
}
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 'binary':
return binaryWrite(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 binarySlice (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 = Buffer._augment(this.subarray(start, end))
} else {
var sliceLen = end - start
newBuf = new Buffer(sliceLen, undefined)
for (var i = 0; i < sliceLen; i++) {
newBuf[i] = this[i + start]
}
}
if (newBuf.length) newBuf.parent = this.parent || this
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 must be a Buffer instance')
if (value > max || value < min) throw new RangeError('value 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) checkInt(this, value, offset, byteLength, Math.pow(2, 8 * byteLength), 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) checkInt(this, value, offset, byteLength, Math.pow(2, 8 * byteLength), 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 = value < 0 ? 1 : 0
this[offset] = value & 0xFF
while (++i < byteLength && (mul *= 0x100)) {
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 = value < 0 ? 1 : 0
this[offset + i] = value & 0xFF
while (--i >= 0 && (mul *= 0x100)) {
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 (value > max || value < min) throw new RangeError('value is out of bounds')
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 oo