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"use strict";
module.exports = LongBits;
var util = require("../util/minimal");
/**
* Constructs new long bits.
* @classdesc Helper class for working with the low and high bits of a 64 bit value.
* @memberof util
* @constructor
* @param {number} lo Low 32 bits, unsigned
* @param {number} hi High 32 bits, unsigned
*/
function LongBits(lo, hi) {
// note that the casts below are theoretically unnecessary as of today, but older statically
// generated converter code might still call the ctor with signed 32bits. kept for compat.
/**
* Low bits.
* @type {number}
*/
this.lo = lo >>> 0;
/**
* High bits.
* @type {number}
*/
this.hi = hi >>> 0;
}
/**
* Zero bits.
* @memberof util.LongBits
* @type {util.LongBits}
*/
var zero = LongBits.zero = new LongBits(0, 0);
zero.toNumber = function() { return 0; };
zero.zzEncode = zero.zzDecode = function() { return this; };
zero.length = function() { return 1; };
/**
* Zero hash.
* @memberof util.LongBits
* @type {string}
*/
var zeroHash = LongBits.zeroHash = "\0\0\0\0\0\0\0\0";
/**
* Constructs new long bits from the specified number.
* @param {number} value Value
* @returns {util.LongBits} Instance
*/
LongBits.fromNumber = function fromNumber(value) {
if (value === 0)
return zero;
var sign = value < 0;
if (sign)
value = -value;
var lo = value >>> 0,
hi = (value - lo) / 4294967296 >>> 0;
if (sign) {
hi = ~hi >>> 0;
lo = ~lo >>> 0;
if (++lo > 4294967295) {
lo = 0;
if (++hi > 4294967295)
hi = 0;
}
}
return new LongBits(lo, hi);
};
/**
* Constructs new long bits from a number, long or string.
* @param {Long|number|string} value Value
* @returns {util.LongBits} Instance
*/
LongBits.from = function from(value) {
if (typeof value === "number")
return LongBits.fromNumber(value);
if (util.isString(value)) {
/* istanbul ignore else */
if (util.Long)
value = util.Long.fromString(value);
else
return LongBits.fromNumber(parseInt(value, 10));
}
return value.low || value.high ? new LongBits(value.low >>> 0, value.high >>> 0) : zero;
};
/**
* Converts this long bits to a possibly unsafe JavaScript number.
* @param {boolean} [unsigned=false] Whether unsigned or not
* @returns {number} Possibly unsafe number
*/
LongBits.prototype.toNumber = function toNumber(unsigned) {
if (!unsigned && this.hi >>> 31) {
var lo = ~this.lo + 1 >>> 0,
hi = ~this.hi >>> 0;
if (!lo)
hi = hi + 1 >>> 0;
return -(lo + hi * 4294967296);
}
return this.lo + this.hi * 4294967296;
};
/**
* Converts this long bits to a long.
* @param {boolean} [unsigned=false] Whether unsigned or not
* @returns {Long} Long
*/
LongBits.prototype.toLong = function toLong(unsigned) {
return util.Long
? new util.Long(this.lo | 0, this.hi | 0, Boolean(unsigned))
/* istanbul ignore next */
: { low: this.lo | 0, high: this.hi | 0, unsigned: Boolean(unsigned) };
};
var charCodeAt = String.prototype.charCodeAt;
/**
* Constructs new long bits from the specified 8 characters long hash.
* @param {string} hash Hash
* @returns {util.LongBits} Bits
*/
LongBits.fromHash = function fromHash(hash) {
if (hash === zeroHash)
return zero;
return new LongBits(
( charCodeAt.call(hash, 0)
| charCodeAt.call(hash, 1) << 8
| charCodeAt.call(hash, 2) << 16
| charCodeAt.call(hash, 3) << 24) >>> 0
,
( charCodeAt.call(hash, 4)
| charCodeAt.call(hash, 5) << 8
| charCodeAt.call(hash, 6) << 16
| charCodeAt.call(hash, 7) << 24) >>> 0
);
};
/**
* Converts this long bits to a 8 characters long hash.
* @returns {string} Hash
*/
LongBits.prototype.toHash = function toHash() {
return String.fromCharCode(
this.lo & 255,
this.lo >>> 8 & 255,
this.lo >>> 16 & 255,
this.lo >>> 24 ,
this.hi & 255,
this.hi >>> 8 & 255,
this.hi >>> 16 & 255,
this.hi >>> 24
);
};
/**
* Zig-zag encodes this long bits.
* @returns {util.LongBits} `this`
*/
LongBits.prototype.zzEncode = function zzEncode() {
var mask = this.hi >> 31;
this.hi = ((this.hi << 1 | this.lo >>> 31) ^ mask) >>> 0;
this.lo = ( this.lo << 1 ^ mask) >>> 0;
return this;
};
/**
* Zig-zag decodes this long bits.
* @returns {util.LongBits} `this`
*/
LongBits.prototype.zzDecode = function zzDecode() {
var mask = -(this.lo & 1);
this.lo = ((this.lo >>> 1 | this.hi << 31) ^ mask) >>> 0;
this.hi = ( this.hi >>> 1 ^ mask) >>> 0;
return this;
};
/**
* Calculates the length of this longbits when encoded as a varint.
* @returns {number} Length
*/
LongBits.prototype.length = function length() {
var part0 = this.lo,
part1 = (this.lo >>> 28 | this.hi << 4) >>> 0,
part2 = this.hi >>> 24;
return part2 === 0
? part1 === 0
? part0 < 16384
? part0 < 128 ? 1 : 2
: part0 < 2097152 ? 3 : 4
: part1 < 16384
? part1 < 128 ? 5 : 6
: part1 < 2097152 ? 7 : 8
: part2 < 128 ? 9 : 10;
};
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