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node_modules/protobufjs/src/util/longbits.js

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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;
+};