go-ethereum/cmd/mist/assets/ext/big.js
2014-10-23 15:48:53 +02:00

398 lines
14 KiB
JavaScript

// Copyright (c) 2013-2014, Jeffrey Wilcke. All rights reserved.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
// MA 02110-1301 USA
var bigInt = (function () {
var base = 10000000, logBase = 7;
var sign = {
positive: false,
negative: true
};
var normalize = function (first, second) {
var a = first.value, b = second.value;
var length = a.length > b.length ? a.length : b.length;
for (var i = 0; i < length; i++) {
a[i] = a[i] || 0;
b[i] = b[i] || 0;
}
for (var i = length - 1; i >= 0; i--) {
if (a[i] === 0 && b[i] === 0) {
a.pop();
b.pop();
} else break;
}
if (!a.length) a = [0], b = [0];
first.value = a;
second.value = b;
};
var parse = function (text, first) {
if (typeof text === "object") return text;
text += "";
var s = sign.positive, value = [];
if (text[0] === "-") {
s = sign.negative;
text = text.slice(1);
}
var base = 10;
if (text.slice(0, 2) == "0x") {
base = 16;
text = text.slice(2);
}
else {
var texts = text.split("e");
if (texts.length > 2) throw new Error("Invalid integer");
if (texts[1]) {
var exp = texts[1];
if (exp[0] === "+") exp = exp.slice(1);
exp = parse(exp);
if (exp.lesser(0)) throw new Error("Cannot include negative exponent part for integers");
while (exp.notEquals(0)) {
texts[0] += "0";
exp = exp.prev();
}
}
text = texts[0];
}
if (text === "-0") text = "0";
text = text.toUpperCase();
var isValid = (base == 16 ? /^[0-9A-F]*$/ : /^[0-9]+$/).test(text);
if (!isValid) throw new Error("Invalid integer");
if (base == 16) {
var val = bigInt(0);
while (text.length) {
v = text.charCodeAt(0) - 48;
if (v > 9)
v -= 7;
text = text.slice(1);
val = val.times(16).plus(v);
}
return val;
}
else {
while (text.length) {
var divider = text.length > logBase ? text.length - logBase : 0;
value.push(+text.slice(divider));
text = text.slice(0, divider);
}
var val = bigInt(value, s);
if (first) normalize(first, val);
return val;
}
};
var goesInto = function (a, b) {
var a = bigInt(a, sign.positive), b = bigInt(b, sign.positive);
if (a.equals(0)) throw new Error("Cannot divide by 0");
var n = 0;
do {
var inc = 1;
var c = bigInt(a.value, sign.positive), t = c.times(10);
while (t.lesser(b)) {
c = t;
inc *= 10;
t = t.times(10);
}
while (c.lesserOrEquals(b)) {
b = b.minus(c);
n += inc;
}
} while (a.lesserOrEquals(b));
return {
remainder: b.value,
result: n
};
};
var bigInt = function (value, s) {
var self = {
value: value,
sign: s
};
var o = {
value: value,
sign: s,
negate: function (m) {
var first = m || self;
return bigInt(first.value, !first.sign);
},
abs: function (m) {
var first = m || self;
return bigInt(first.value, sign.positive);
},
add: function (n, m) {
var s, first = self, second;
if (m) (first = parse(n)) && (second = parse(m));
else second = parse(n, first);
s = first.sign;
if (first.sign !== second.sign) {
first = bigInt(first.value, sign.positive);
second = bigInt(second.value, sign.positive);
return s === sign.positive ?
o.subtract(first, second) :
o.subtract(second, first);
}
normalize(first, second);
var a = first.value, b = second.value;
var result = [],
carry = 0;
for (var i = 0; i < a.length || carry > 0; i++) {
var sum = (a[i] || 0) + (b[i] || 0) + carry;
carry = sum >= base ? 1 : 0;
sum -= carry * base;
result.push(sum);
}
return bigInt(result, s);
},
plus: function (n, m) {
return o.add(n, m);
},
subtract: function (n, m) {
var first = self, second;
if (m) (first = parse(n)) && (second = parse(m));
else second = parse(n, first);
if (first.sign !== second.sign) return o.add(first, o.negate(second));
if (first.sign === sign.negative) return o.subtract(o.negate(second), o.negate(first));
if (o.compare(first, second) === -1) return o.negate(o.subtract(second, first));
var a = first.value, b = second.value;
var result = [],
borrow = 0;
for (var i = 0; i < a.length; i++) {
var tmp = a[i] - borrow;
borrow = tmp < b[i] ? 1 : 0;
var minuend = (borrow * base) + tmp - b[i];
result.push(minuend);
}
return bigInt(result, sign.positive);
},
minus: function (n, m) {
return o.subtract(n, m);
},
multiply: function (n, m) {
var s, first = self, second;
if (m) (first = parse(n)) && (second = parse(m));
else second = parse(n, first);
s = first.sign !== second.sign;
var a = first.value, b = second.value;
var resultSum = [];
for (var i = 0; i < a.length; i++) {
resultSum[i] = [];
var j = i;
while (j--) {
resultSum[i].push(0);
}
}
var carry = 0;
for (var i = 0; i < a.length; i++) {
var x = a[i];
for (var j = 0; j < b.length || carry > 0; j++) {
var y = b[j];
var product = y ? (x * y) + carry : carry;
carry = product > base ? Math.floor(product / base) : 0;
product -= carry * base;
resultSum[i].push(product);
}
}
var max = -1;
for (var i = 0; i < resultSum.length; i++) {
var len = resultSum[i].length;
if (len > max) max = len;
}
var result = [], carry = 0;
for (var i = 0; i < max || carry > 0; i++) {
var sum = carry;
for (var j = 0; j < resultSum.length; j++) {
sum += resultSum[j][i] || 0;
}
carry = sum > base ? Math.floor(sum / base) : 0;
sum -= carry * base;
result.push(sum);
}
return bigInt(result, s);
},
times: function (n, m) {
return o.multiply(n, m);
},
divmod: function (n, m) {
var s, first = self, second;
if (m) (first = parse(n)) && (second = parse(m));
else second = parse(n, first);
s = first.sign !== second.sign;
if (bigInt(first.value, first.sign).equals(0)) return {
quotient: bigInt([0], sign.positive),
remainder: bigInt([0], sign.positive)
};
if (second.equals(0)) throw new Error("Cannot divide by zero");
var a = first.value, b = second.value;
var result = [], remainder = [];
for (var i = a.length - 1; i >= 0; i--) {
var n = [a[i]].concat(remainder);
var quotient = goesInto(b, n);
result.push(quotient.result);
remainder = quotient.remainder;
}
result.reverse();
return {
quotient: bigInt(result, s),
remainder: bigInt(remainder, first.sign)
};
},
divide: function (n, m) {
return o.divmod(n, m).quotient;
},
over: function (n, m) {
return o.divide(n, m);
},
mod: function (n, m) {
return o.divmod(n, m).remainder;
},
pow: function (n, m) {
var first = self, second;
if (m) (first = parse(n)) && (second = parse(m));
else second = parse(n, first);
var a = first, b = second;
if (b.lesser(0)) return ZERO;
if (b.equals(0)) return ONE;
var result = bigInt(a.value, a.sign);
if (b.mod(2).equals(0)) {
var c = result.pow(b.over(2));
return c.times(c);
} else {
return result.times(result.pow(b.minus(1)));
}
},
next: function (m) {
var first = m || self;
return o.add(first, 1);
},
prev: function (m) {
var first = m || self;
return o.subtract(first, 1);
},
compare: function (n, m) {
var first = self, second;
if (m) (first = parse(n)) && (second = parse(m, first));
else second = parse(n, first);
normalize(first, second);
if (first.value.length === 1 && second.value.length === 1 && first.value[0] === 0 && second.value[0] === 0) return 0;
if (second.sign !== first.sign) return first.sign === sign.positive ? 1 : -1;
var multiplier = first.sign === sign.positive ? 1 : -1;
var a = first.value, b = second.value;
for (var i = a.length - 1; i >= 0; i--) {
if (a[i] > b[i]) return 1 * multiplier;
if (b[i] > a[i]) return -1 * multiplier;
}
return 0;
},
compareAbs: function (n, m) {
var first = self, second;
if (m) (first = parse(n)) && (second = parse(m, first));
else second = parse(n, first);
first.sign = second.sign = sign.positive;
return o.compare(first, second);
},
equals: function (n, m) {
return o.compare(n, m) === 0;
},
notEquals: function (n, m) {
return !o.equals(n, m);
},
lesser: function (n, m) {
return o.compare(n, m) < 0;
},
greater: function (n, m) {
return o.compare(n, m) > 0;
},
greaterOrEquals: function (n, m) {
return o.compare(n, m) >= 0;
},
lesserOrEquals: function (n, m) {
return o.compare(n, m) <= 0;
},
isPositive: function (m) {
var first = m || self;
return first.sign === sign.positive;
},
isNegative: function (m) {
var first = m || self;
return first.sign === sign.negative;
},
isEven: function (m) {
var first = m || self;
return first.value[0] % 2 === 0;
},
isOdd: function (m) {
var first = m || self;
return first.value[0] % 2 === 1;
},
toString: function (m) {
var first = m || self;
var str = "", len = first.value.length;
while (len--) {
if (first.value[len].toString().length === 8) str += first.value[len];
else str += (base.toString() + first.value[len]).slice(-logBase);
}
while (str[0] === "0") {
str = str.slice(1);
}
if (!str.length) str = "0";
var s = (first.sign === sign.positive || str == "0") ? "" : "-";
return s + str;
},
toHex: function (m) {
var first = m || self;
var str = "";
var l = this.abs();
while (l > 0) {
var qr = l.divmod(256);
var b = qr.remainder.toJSNumber();
str = (b >> 4).toString(16) + (b & 15).toString(16) + str;
l = qr.quotient;
}
return (this.isNegative() ? "-" : "") + "0x" + str;
},
toJSNumber: function (m) {
return +o.toString(m);
},
valueOf: function (m) {
return o.toJSNumber(m);
}
};
return o;
};
var ZERO = bigInt([0], sign.positive);
var ONE = bigInt([1], sign.positive);
var MINUS_ONE = bigInt([1], sign.negative);
var fnReturn = function (a) {
if (typeof a === "undefined") return ZERO;
return parse(a);
};
fnReturn.zero = ZERO;
fnReturn.one = ONE;
fnReturn.minusOne = MINUS_ONE;
return fnReturn;
})();
if (typeof module !== "undefined") {
module.exports = bigInt;
}