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// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
var SlowBuffer = process.binding('buffer').SlowBuffer;
var assert = require('assert');
exports.INSPECT_MAX_BYTES = 50;
function toHex(n) {
if (n < 16) return '0' + n.toString(16);
return n.toString(16);
}
SlowBuffer.prototype.inspect = function() {
var out = [],
len = this.length;
for (var i = 0; i < len; i++) {
out[i] = toHex(this[i]);
if (i == exports.INSPECT_MAX_BYTES) {
out[i + 1] = '...';
break;
}
}
return '<SlowBuffer ' + out.join(' ') + '>';
};
SlowBuffer.prototype.hexSlice = function(start, end) {
var len = this.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(this[i]);
}
return out;
};
SlowBuffer.prototype.toString = function(encoding, start, end) {
encoding = String(encoding || 'utf8').toLowerCase();
start = +start || 0;
if (typeof end == 'undefined') end = this.length;
// Fastpath empty strings
if (+end == start) {
return '';
}
switch (encoding) {
case 'hex':
return this.hexSlice(start, end);
case 'utf8':
case 'utf-8':
return this.utf8Slice(start, end);
case 'ascii':
return this.asciiSlice(start, end);
case 'binary':
return this.binarySlice(start, end);
case 'base64':
return this.base64Slice(start, end);
case 'ucs2':
case 'ucs-2':
return this.ucs2Slice(start, end);
default:
throw new Error('Unknown encoding');
}
};
SlowBuffer.prototype.hexWrite = function(string, offset, length) {
offset = +offset || 0;
var remaining = this.length - offset;
if (!length) {
length = remaining;
} else {
length = +length;
if (length > remaining) {
length = remaining;
}
}
// must be an even number of digits
var strLen = string.length;
if (strLen % 2) {
throw new Error('Invalid hex string');
}
if (length > strLen / 2) {
length = strLen / 2;
}
for (var i = 0; i < length; i++) {
var byte = parseInt(string.substr(i * 2, 2), 16);
if (isNaN(byte)) throw new Error('Invalid hex string');
this[offset + i] = byte;
}
return i;
};
SlowBuffer.prototype.write = function(string, offset, length, encoding) {
// Support both (string, offset, length, encoding)
// and the legacy (string, encoding, offset, length)
if (isFinite(offset)) {
if (!isFinite(length)) {
encoding = length;
length = undefined;
}
} else { // legacy
var swap = encoding;
encoding = offset;
offset = length;
length = swap;
}
offset = +offset || 0;
var remaining = this.length - offset;
if (!length) {
length = remaining;
} else {
length = +length;
if (length > remaining) {
length = remaining;
}
}
encoding = String(encoding || 'utf8').toLowerCase();
switch (encoding) {
case 'hex':
return this.hexWrite(string, offset, length);
case 'utf8':
case 'utf-8':
return this.utf8Write(string, offset, length);
case 'ascii':
return this.asciiWrite(string, offset, length);
case 'binary':
return this.binaryWrite(string, offset, length);
case 'base64':
return this.base64Write(string, offset, length);
case 'ucs2':
case 'ucs-2':
return this.ucs2Write(string, offset, length);
default:
throw new Error('Unknown encoding');
}
};
// slice(start, end)
SlowBuffer.prototype.slice = function(start, end) {
if (end === undefined) end = this.length;
if (end > this.length) {
throw new Error('oob');
}
if (start > end) {
throw new Error('oob');
}
return new Buffer(this, end - start, +start);
};
// Buffer
function Buffer(subject, encoding, offset) {
if (!(this instanceof Buffer)) {
return new Buffer(subject, encoding, offset);
}
var type;
// Are we slicing?
if (typeof offset === 'number') {
this.length = encoding;
this.parent = subject;
this.offset = offset;
} else {
// Find the length
switch (type = typeof subject) {
case 'number':
this.length = subject;
break;
case 'string':
this.length = Buffer.byteLength(subject, encoding);
break;
case 'object': // Assume object is an array
this.length = subject.length;
break;
default:
throw new Error('First argument needs to be a number, ' +
'array or string.');
}
if (this.length > Buffer.poolSize) {
// Big buffer, just alloc one.
this.parent = new SlowBuffer(this.length);
this.offset = 0;
} else {
// Small buffer.
if (!pool || pool.length - pool.used < this.length) allocPool();
this.parent = pool;
this.offset = pool.used;
pool.used += this.length;
}
// Treat array-ish objects as a byte array.
if (isArrayIsh(subject)) {
for (var i = 0; i < this.length; i++) {
this.parent[i + this.offset] = subject[i];
}
} else if (type == 'string') {
// We are a string
this.length = this.write(subject, 0, encoding);
}
}
SlowBuffer.makeFastBuffer(this.parent, this, this.offset, this.length);
}
function isArrayIsh(subject) {
return Array.isArray(subject) || Buffer.isBuffer(subject) ||
subject && typeof subject === 'object' &&
typeof subject.length === 'number';
}
exports.SlowBuffer = SlowBuffer;
exports.Buffer = Buffer;
Buffer.poolSize = 8 * 1024;
var pool;
function allocPool() {
pool = new SlowBuffer(Buffer.poolSize);
pool.used = 0;
}
// Static methods
Buffer.isBuffer = function isBuffer(b) {
return b instanceof Buffer || b instanceof SlowBuffer;
};
// Inspect
Buffer.prototype.inspect = function inspect() {
var out = [],
len = this.length;
for (var i = 0; i < len; i++) {
out[i] = toHex(this.parent[i + this.offset]);
if (i == exports.INSPECT_MAX_BYTES) {
out[i + 1] = '...';
break;
}
}
return '<Buffer ' + out.join(' ') + '>';
};
Buffer.prototype.get = function get(i) {
if (i < 0 || i >= this.length) throw new Error('oob');
return this.parent[this.offset + i];
};
Buffer.prototype.set = function set(i, v) {
if (i < 0 || i >= this.length) throw new Error('oob');
return this.parent[this.offset + i] = v;
};
// write(string, offset = 0, length = buffer.length-offset, encoding = 'utf8')
Buffer.prototype.write = function(string, offset, length, encoding) {
// Support both (string, offset, length, encoding)
// and the legacy (string, encoding, offset, length)
if (isFinite(offset)) {
if (!isFinite(length)) {
encoding = length;
length = undefined;
}
} else { // legacy
var swap = encoding;
encoding = offset;
offset = length;
length = swap;
}
offset = +offset || 0;
var remaining = this.length - offset;
if (!length) {
length = remaining;
} else {
length = +length;
if (length > remaining) {
length = remaining;
}
}
encoding = String(encoding || 'utf8').toLowerCase();
var ret;
switch (encoding) {
case 'hex':
ret = this.parent.hexWrite(string, this.offset + offset, length);
break;
case 'utf8':
case 'utf-8':
ret = this.parent.utf8Write(string, this.offset + offset, length);
break;
case 'ascii':
ret = this.parent.asciiWrite(string, this.offset + offset, length);
break;
case 'binary':
ret = this.parent.binaryWrite(string, this.offset + offset, length);
break;
case 'base64':
// Warning: maxLength not taken into account in base64Write
ret = this.parent.base64Write(string, this.offset + offset, length);
break;
case 'ucs2':
case 'ucs-2':
ret = this.parent.ucs2Write(string, this.offset + offset, length);
break;
default:
throw new Error('Unknown encoding');
}
Buffer._charsWritten = SlowBuffer._charsWritten;
return ret;
};
// toString(encoding, start=0, end=buffer.length)
Buffer.prototype.toString = function(encoding, start, end) {
encoding = String(encoding || 'utf8').toLowerCase();
if (typeof start == 'undefined' || start < 0) {
start = 0;
} else if (start > this.length) {
start = this.length;
}
if (typeof end == 'undefined' || end > this.length) {
end = this.length;
} else if (end < 0) {
end = 0;
}
start = start + this.offset;
end = end + this.offset;
switch (encoding) {
case 'hex':
return this.parent.hexSlice(start, end);
case 'utf8':
case 'utf-8':
return this.parent.utf8Slice(start, end);
case 'ascii':
return this.parent.asciiSlice(start, end);
case 'binary':
return this.parent.binarySlice(start, end);
case 'base64':
return this.parent.base64Slice(start, end);
case 'ucs2':
case 'ucs-2':
return this.parent.ucs2Slice(start, end);
default:
throw new Error('Unknown encoding');
}
};
// byteLength
Buffer.byteLength = SlowBuffer.byteLength;
// fill(value, start=0, end=buffer.length)
Buffer.prototype.fill = function fill(value, start, end) {
value || (value = 0);
start || (start = 0);
end || (end = this.length);
if (typeof value === 'string') {
value = value.charCodeAt(0);
}
if (!(typeof value === 'number') || isNaN(value)) {
throw new Error('value is not a number');
}
if (end < start) throw new Error('end < start');
// Fill 0 bytes; we're done
if (end === start) return 0;
if (this.length == 0) return 0;
if (start < 0 || start >= this.length) {
throw new Error('start out of bounds');
}
if (end < 0 || end > this.length) {
throw new Error('end out of bounds');
}
return this.parent.fill(value,
start + this.offset,
end + this.offset);
};
// copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length)
Buffer.prototype.copy = function(target, target_start, start, end) {
var source = this;
start || (start = 0);
end || (end = this.length);
target_start || (target_start = 0);
if (end < start) throw new Error('sourceEnd < sourceStart');
// Copy 0 bytes; we're done
if (end === start) return 0;
if (target.length == 0 || source.length == 0) return 0;
if (target_start < 0 || target_start >= target.length) {
throw new Error('targetStart out of bounds');
}
if (start < 0 || start >= source.length) {
throw new Error('sourceStart out of bounds');
}
if (end < 0 || end > source.length) {
throw new Error('sourceEnd out of bounds');
}
// Are we oob?
if (end > this.length) {
end = this.length;
}
if (target.length - target_start < end - start) {
end = target.length - target_start + start;
}
return this.parent.copy(target.parent,
target_start + target.offset,
start + this.offset,
end + this.offset);
};
// slice(start, end)
Buffer.prototype.slice = function(start, end) {
if (end === undefined) end = this.length;
if (end > this.length) throw new Error('oob');
if (start > end) throw new Error('oob');
return new Buffer(this.parent, end - start, +start + this.offset);
};
// Legacy methods for backwards compatibility.
Buffer.prototype.utf8Slice = function(start, end) {
return this.toString('utf8', start, end);
};
Buffer.prototype.binarySlice = function(start, end) {
return this.toString('binary', start, end);
};
Buffer.prototype.asciiSlice = function(start, end) {
return this.toString('ascii', start, end);
};
Buffer.prototype.utf8Write = function(string, offset) {
return this.write(string, offset, 'utf8');
};
Buffer.prototype.binaryWrite = function(string, offset) {
return this.write(string, offset, 'binary');
};
Buffer.prototype.asciiWrite = function(string, offset) {
return this.write(string, offset, 'ascii');
};
Buffer.prototype.readUInt8 = function(offset, noAssert) {
var buffer = this;
if (!noAssert) {
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset < buffer.length,
'Trying to read beyond buffer length');
}
return buffer[offset];
};
function readUInt16(buffer, offset, isBigEndian, noAssert) {
var val = 0;
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 1 < buffer.length,
'Trying to read beyond buffer length');
}
if (isBigEndian) {
val = buffer[offset] << 8;
val |= buffer[offset + 1];
} else {
val = buffer[offset];
val |= buffer[offset + 1] << 8;
}
return val;
}
Buffer.prototype.readUInt16LE = function(offset, noAssert) {
return readUInt16(this, offset, false, noAssert);
};
Buffer.prototype.readUInt16BE = function(offset, noAssert) {
return readUInt16(this, offset, true, noAssert);
};
function readUInt32(buffer, offset, isBigEndian, noAssert) {
var val = 0;
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 3 < buffer.length,
'Trying to read beyond buffer length');
}
if (isBigEndian) {
val = buffer[offset + 1] << 16;
val |= buffer[offset + 2] << 8;
val |= buffer[offset + 3];
val = val + (buffer[offset] << 24 >>> 0);
} else {
val = buffer[offset + 2] << 16;
val |= buffer[offset + 1] << 8;
val |= buffer[offset];
val = val + (buffer[offset + 3] << 24 >>> 0);
}
return val;
}
Buffer.prototype.readUInt32LE = function(offset, noAssert) {
return readUInt32(this, offset, false, noAssert);
};
Buffer.prototype.readUInt32BE = function(offset, noAssert) {
return readUInt32(this, offset, true, noAssert);
};
/*
* Signed integer types, yay team! A reminder on how two's complement actually
* works. The first bit is the signed bit, i.e. tells us whether or not the
* number should be positive or negative. If the two's complement value is
* positive, then we're done, as it's equivalent to the unsigned representation.
*
* Now if the number is positive, you're pretty much done, you can just leverage
* the unsigned translations and return those. Unfortunately, negative numbers
* aren't quite that straightforward.
*
* At first glance, one might be inclined to use the traditional formula to
* translate binary numbers between the positive and negative values in two's
* complement. (Though it doesn't quite work for the most negative value)
* Mainly:
* - invert all the bits
* - add one to the result
*
* Of course, this doesn't quite work in Javascript. Take for example the value
* of -128. This could be represented in 16 bits (big-endian) as 0xff80. But of
* course, Javascript will do the following:
*
* > ~0xff80
* -65409
*
* Whoh there, Javascript, that's not quite right. But wait, according to
* Javascript that's perfectly correct. When Javascript ends up seeing the
* constant 0xff80, it has no notion that it is actually a signed number. It
* assumes that we've input the unsigned value 0xff80. Thus, when it does the
* binary negation, it casts it into a signed value, (positive 0xff80). Then
* when you perform binary negation on that, it turns it into a negative number.
*
* Instead, we're going to have to use the following general formula, that works
* in a rather Javascript friendly way. I'm glad we don't support this kind of
* weird numbering scheme in the kernel.
*
* (BIT-MAX - (unsigned)val + 1) * -1
*
* The astute observer, may think that this doesn't make sense for 8-bit numbers
* (really it isn't necessary for them). However, when you get 16-bit numbers,
* you do. Let's go back to our prior example and see how this will look:
*
* (0xffff - 0xff80 + 1) * -1
* (0x007f + 1) * -1
* (0x0080) * -1
*/
Buffer.prototype.readInt8 = function(offset, noAssert) {
var buffer = this;
var neg;
if (!noAssert) {
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset < buffer.length,
'Trying to read beyond buffer length');
}
neg = buffer[offset] & 0x80;
if (!neg) {
return (buffer[offset]);
}
return ((0xff - buffer[offset] + 1) * -1);
};
function readInt16(buffer, offset, isBigEndian, noAssert) {
var neg;
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 1 < buffer.length,
'Trying to read beyond buffer length');
}
val = readUInt16(buffer, offset, isBigEndian, noAssert);
neg = val & 0x8000;
if (!neg) {
return val;
}
return (0xffff - val + 1) * -1;
}
Buffer.prototype.readInt16LE = function(offset, noAssert) {
return readInt16(this, offset, false, noAssert);
};
Buffer.prototype.readInt16BE = function(offset, noAssert) {
return readInt16(this, offset, true, noAssert);
};
function readInt32(buffer, offset, isBigEndian, noAssert) {
var neg;
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 3 < buffer.length,
'Trying to read beyond buffer length');
}
val = readUInt32(buffer, offset, isBigEndian, noAssert);
neg = val & 0x80000000;
if (!neg) {
return (val);
}
return (0xffffffff - val + 1) * -1;
}
Buffer.prototype.readInt32LE = function(offset, noAssert) {
return readInt32(this, offset, false, noAssert);
};
Buffer.prototype.readInt32BE = function(offset, noAssert) {
return readInt32(this, offset, true, noAssert);
};
function readFloat(buffer, offset, isBigEndian, noAssert) {
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset + 3 < buffer.length,
'Trying to read beyond buffer length');
}
return require('buffer_ieee754').readIEEE754(buffer, offset, isBigEndian,
23, 4);
}
Buffer.prototype.readFloatLE = function(offset, noAssert) {
return readFloat(this, offset, false, noAssert);
};
Buffer.prototype.readFloatBE = function(offset, noAssert) {
return readFloat(this, offset, true, noAssert);
};
function readDouble(buffer, offset, isBigEndian, noAssert) {
if (!noAssert) {
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset + 7 < buffer.length,
'Trying to read beyond buffer length');
}
return require('buffer_ieee754').readIEEE754(buffer, offset, isBigEndian,
52, 8);
}
Buffer.prototype.readDoubleLE = function(offset, noAssert) {
return readDouble(this, offset, false, noAssert);
};
Buffer.prototype.readDoubleBE = function(offset, noAssert) {
return readDouble(this, offset, true, noAssert);
};
/*
* We have to make sure that the value is a valid integer. This means that it is
* non-negative. It has no fractional component and that it does not exceed the
* maximum allowed value.
*
* value The number to check for validity
*
* max The maximum value
*/
function verifuint(value, max) {
assert.ok(typeof (value) == 'number',
'cannot write a non-number as a number');
assert.ok(value >= 0,
'specified a negative value for writing an unsigned value');
assert.ok(value <= max, 'value is larger than maximum value for type');
assert.ok(Math.floor(value) === value, 'value has a fractional component');
}
Buffer.prototype.writeUInt8 = function(value, offset, noAssert) {
var buffer = this;
if (!noAssert) {
assert.ok(value !== undefined && value !== null,
'missing value');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset < buffer.length,
'trying to write beyond buffer length');
verifuint(value, 0xff);
}
buffer[offset] = value;
};
function writeUInt16(buffer, value, offset, isBigEndian, noAssert) {
if (!noAssert) {
assert.ok(value !== undefined && value !== null,
'missing value');
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 1 < buffer.length,
'trying to write beyond buffer length');
verifuint(value, 0xffff);
}
if (isBigEndian) {
buffer[offset] = (value & 0xff00) >>> 8;
buffer[offset + 1] = value & 0x00ff;
} else {
buffer[offset + 1] = (value & 0xff00) >>> 8;
buffer[offset] = value & 0x00ff;
}
}
Buffer.prototype.writeUInt16LE = function(value, offset, noAssert) {
writeUInt16(this, value, offset, false, noAssert);
};
Buffer.prototype.writeUInt16BE = function(value, offset, noAssert) {
writeUInt16(this, value, offset, true, noAssert);
};
function writeUInt32(buffer, value, offset, isBigEndian, noAssert) {
if (!noAssert) {
assert.ok(value !== undefined && value !== null,
'missing value');
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset + 3 < buffer.length,
'trying to write beyond buffer length');
verifuint(value, 0xffffffff);
}
if (isBigEndian) {
buffer[offset] = (value >>> 24) & 0xff;
buffer[offset + 1] = (value >>> 16) & 0xff;
buffer[offset + 2] = (value >>> 8) & 0xff;
buffer[offset + 3] = value & 0xff;
} else {
buffer[offset + 3] = (value >>> 24) & 0xff;
buffer[offset + 2] = (value >>> 16) & 0xff;
buffer[offset + 1] = (value >>> 8) & 0xff;
buffer[offset] = value & 0xff;
}
}
Buffer.prototype.writeUInt32LE = function(value, offset, noAssert) {
writeUInt32(this, value, offset, false, noAssert);
};
Buffer.prototype.writeUInt32BE = function(value, offset, noAssert) {
writeUInt32(this, value, offset, true, noAssert);
};
/*
* We now move onto our friends in the signed number category. Unlike unsigned
* numbers, we're going to have to worry a bit more about how we put values into
* arrays. Since we are only worrying about signed 32-bit values, we're in
* slightly better shape. Unfortunately, we really can't do our favorite binary
* & in this system. It really seems to do the wrong thing. For example:
*
* > -32 & 0xff
* 224
*
* What's happening above is really: 0xe0 & 0xff = 0xe0. However, the results of
* this aren't treated as a signed number. Ultimately a bad thing.
*
* What we're going to want to do is basically create the unsigned equivalent of
* our representation and pass that off to the wuint* functions. To do that
* we're going to do the following:
*
* - if the value is positive
* we can pass it directly off to the equivalent wuint
* - if the value is negative
* we do the following computation:
* mb + val + 1, where
* mb is the maximum unsigned value in that byte size
* val is the Javascript negative integer
*
*
* As a concrete value, take -128. In signed 16 bits this would be 0xff80. If
* you do out the computations:
*
* 0xffff - 128 + 1
* 0xffff - 127
* 0xff80
*
* You can then encode this value as the signed version. This is really rather
* hacky, but it should work and get the job done which is our goal here.
*/
/*
* A series of checks to make sure we actually have a signed 32-bit number
*/
function verifsint(value, max, min) {
assert.ok(typeof (value) == 'number',
'cannot write a non-number as a number');
assert.ok(value <= max, 'value larger than maximum allowed value');
assert.ok(value >= min, 'value smaller than minimum allowed value');
assert.ok(Math.floor(value) === value, 'value has a fractional component');
}
function verifIEEE754(value, max, min) {
assert.ok(typeof (value) == 'number',
'cannot write a non-number as a number');
assert.ok(value <= max, 'value larger than maximum allowed value');
assert.ok(value >= min, 'value smaller than minimum allowed value');
}
Buffer.prototype.writeInt8 = function(value, offset, noAssert) {
var buffer = this;
if (!noAssert) {
assert.ok(value !== undefined && value !== null,
'missing value');
assert.ok(offset !== undefined && offset !== null,
'missing offset');
assert.ok(offset < buffer.length,
'Trying to write beyond buffer length');
verifsint(value, 0x7f, -0xf0);
}
if (value >= 0) {
buffer.writeUInt8(value, offset, noAssert);
} else {
buffer.writeUInt8(0xff + value + 1, offset, noAssert);
}
};
function writeInt16(buffer, value, offset, isBigEndian, noAssert) {
if (!noAssert) {
assert.ok(value !== undefined && value !== null,
'missing value');
assert.ok(typeof (isBigEndian) === 'boolean',
'missing or invalid endian');
assert.ok(offset !== undefined && offset !== null,
'missing offset');