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// int64-buffer.js
/*jshint -W018 */ // Confusing use of '!'.
/*jshint -W030 */ // Expected an assignment or function call and instead saw an expression.
/*jshint -W093 */ // Did you mean to return a conditional instead of an assignment?
var Uint64BE, Int64BE, Uint64LE, Int64LE;
!function(exports) {
// constants
var UNDEFINED = "undefined";
var BUFFER = (UNDEFINED !== typeof Buffer) && Buffer;
var UINT8ARRAY = (UNDEFINED !== typeof Uint8Array) && Uint8Array;
var ARRAYBUFFER = (UNDEFINED !== typeof ArrayBuffer) && ArrayBuffer;
var ZERO = [0, 0, 0, 0, 0, 0, 0, 0];
var isArray = Array.isArray || _isArray;
var BIT32 = 4294967296;
var BIT24 = 16777216;
// storage class
var storage; // Array;
// generate classes
Uint64BE = factory("Uint64BE", true, true);
Int64BE = factory("Int64BE", true, false);
Uint64LE = factory("Uint64LE", false, true);
Int64LE = factory("Int64LE", false, false);
// class factory
function factory(name, bigendian, unsigned) {
var posH = bigendian ? 0 : 4;
var posL = bigendian ? 4 : 0;
var pos0 = bigendian ? 0 : 3;
var pos1 = bigendian ? 1 : 2;
var pos2 = bigendian ? 2 : 1;
var pos3 = bigendian ? 3 : 0;
var fromPositive = bigendian ? fromPositiveBE : fromPositiveLE;
var fromNegative = bigendian ? fromNegativeBE : fromNegativeLE;
var proto = Int64.prototype;
var isName = "is" + name;
var _isInt64 = "_" + isName;
// properties
proto.buffer = void 0;
proto.offset = 0;
proto[_isInt64] = true;
// methods
proto.toNumber = toNumber;
proto.toString = toString;
proto.toJSON = toNumber;
proto.toArray = toArray;
// add .toBuffer() method only when Buffer available
if (BUFFER) proto.toBuffer = toBuffer;
// add .toArrayBuffer() method only when Uint8Array available
if (UINT8ARRAY) proto.toArrayBuffer = toArrayBuffer;
// isUint64BE, isInt64BE
Int64[isName] = isInt64;
// CommonJS
exports[name] = Int64;
return Int64;
// constructor
function Int64(buffer, offset, value, raddix) {
if (!(this instanceof Int64)) return new Int64(buffer, offset, value, raddix);
return init(this, buffer, offset, value, raddix);
}
// isUint64BE, isInt64BE
function isInt64(b) {
return !!(b && b[_isInt64]);
}
// initializer
function init(that, buffer, offset, value, raddix) {
if (UINT8ARRAY && ARRAYBUFFER) {
if (buffer instanceof ARRAYBUFFER) buffer = new UINT8ARRAY(buffer);
if (value instanceof ARRAYBUFFER) value = new UINT8ARRAY(value);
}
// Int64BE() style
if (!buffer && !offset && !value && !storage) {
// shortcut to initialize with zero
that.buffer = newArray(ZERO, 0);
return;
}
// Int64BE(value, raddix) style
if (!isValidBuffer(buffer, offset)) {
var _storage = storage || Array;
raddix = offset;
value = buffer;
offset = 0;
buffer = new _storage(8);
}
that.buffer = buffer;
that.offset = offset |= 0;
// Int64BE(buffer, offset) style
if (UNDEFINED === typeof value) return;
// Int64BE(buffer, offset, value, raddix) style
if ("string" === typeof value) {
fromString(buffer, offset, value, raddix || 10);
} else if (isValidBuffer(value, raddix)) {
fromArray(buffer, offset, value, raddix);
} else if ("number" === typeof raddix) {
writeInt32(buffer, offset + posH, value); // high
writeInt32(buffer, offset + posL, raddix); // low
} else if (value > 0) {
fromPositive(buffer, offset, value); // positive
} else if (value < 0) {
fromNegative(buffer, offset, value); // negative
} else {
fromArray(buffer, offset, ZERO, 0); // zero, NaN and others
}
}
function fromString(buffer, offset, str, raddix) {
var pos = 0;
var len = str.length;
var high = 0;
var low = 0;
if (str[0] === "-") pos++;
var sign = pos;
while (pos < len) {
var chr = parseInt(str[pos++], raddix);
if (!(chr >= 0)) break; // NaN
low = low * raddix + chr;
high = high * raddix + Math.floor(low / BIT32);
low %= BIT32;
}
if (sign) {
high = ~high;
if (low) {
low = BIT32 - low;
} else {
high++;
}
}
writeInt32(buffer, offset + posH, high);
writeInt32(buffer, offset + posL, low);
}
function toNumber() {
var buffer = this.buffer;
var offset = this.offset;
var high = readInt32(buffer, offset + posH);
var low = readInt32(buffer, offset + posL);
if (!unsigned) high |= 0; // a trick to get signed
return high ? (high * BIT32 + low) : low;
}
function toString(radix) {
var buffer = this.buffer;
var offset = this.offset;
var high = readInt32(buffer, offset + posH);
var low = readInt32(buffer, offset + posL);
var str = "";
var sign = !unsigned && (high & 0x80000000);
if (sign) {
high = ~high;
low = BIT32 - low;
}
radix = radix || 10;
while (1) {
var mod = (high % radix) * BIT32 + low;
high = Math.floor(high / radix);
low = Math.floor(mod / radix);
str = (mod % radix).toString(radix) + str;
if (!high && !low) break;
}
if (sign) {
str = "-" + str;
}
return str;
}
function writeInt32(buffer, offset, value) {
buffer[offset + pos3] = value & 255;
value = value >> 8;
buffer[offset + pos2] = value & 255;
value = value >> 8;
buffer[offset + pos1] = value & 255;
value = value >> 8;
buffer[offset + pos0] = value & 255;
}
function readInt32(buffer, offset) {
return (buffer[offset + pos0] * BIT24) +
(buffer[offset + pos1] << 16) +
(buffer[offset + pos2] << 8) +
buffer[offset + pos3];
}
}
function toArray(raw) {
var buffer = this.buffer;
var offset = this.offset;
storage = null; // Array
if (raw !== false && offset === 0 && buffer.length === 8 && isArray(buffer)) return buffer;
return newArray(buffer, offset);
}
function toBuffer(raw) {
var buffer = this.buffer;
var offset = this.offset;
storage = BUFFER;
if (raw !== false && offset === 0 && buffer.length === 8 && Buffer.isBuffer(buffer)) return buffer;
var dest = new BUFFER(8);
fromArray(dest, 0, buffer, offset);
return dest;
}
function toArrayBuffer(raw) {
var buffer = this.buffer;
var offset = this.offset;
var arrbuf = buffer.buffer;
storage = UINT8ARRAY;
if (raw !== false && offset === 0 && (arrbuf instanceof ARRAYBUFFER) && arrbuf.byteLength === 8) return arrbuf;
var dest = new UINT8ARRAY(8);
fromArray(dest, 0, buffer, offset);
return dest.buffer;
}
function isValidBuffer(buffer, offset) {
var len = buffer && buffer.length;
offset |= 0;
return len && (offset + 8 <= len) && ("string" !== typeof buffer[offset]);
}
function fromArray(destbuf, destoff, srcbuf, srcoff) {
destoff |= 0;
srcoff |= 0;
for (var i = 0; i < 8; i++) {
destbuf[destoff++] = srcbuf[srcoff++] & 255;
}
}
function newArray(buffer, offset) {
return Array.prototype.slice.call(buffer, offset, offset + 8);
}
function fromPositiveBE(buffer, offset, value) {
var pos = offset + 8;
while (pos > offset) {
buffer[--pos] = value & 255;
value /= 256;
}
}
function fromNegativeBE(buffer, offset, value) {
var pos = offset + 8;
value++;
while (pos > offset) {
buffer[--pos] = ((-value) & 255) ^ 255;
value /= 256;
}
}
function fromPositiveLE(buffer, offset, value) {
var end = offset + 8;
while (offset < end) {
buffer[offset++] = value & 255;
value /= 256;
}
}
function fromNegativeLE(buffer, offset, value) {
var end = offset + 8;
value++;
while (offset < end) {
buffer[offset++] = ((-value) & 255) ^ 255;
value /= 256;
}
}
// https://github.com/retrofox/is-array
function _isArray(val) {
return !!val && "[object Array]" == Object.prototype.toString.call(val);
}
}(typeof exports === 'object' && typeof exports.nodeName !== 'string' ? exports : (this || {}));