101 lines
1.5 KiB
JavaScript
101 lines
1.5 KiB
JavaScript
'use strict';
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// selected so (BASE - 1) * 0x100000000 + 0xffffffff is a safe integer
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var BASE = 1000000;
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function readInt8(buffer) {
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var high = buffer.readInt32BE(0);
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var low = buffer.readUInt32BE(4);
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var sign = '';
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if (high < 0) {
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high = ~high + (low === 0);
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low = (~low + 1) >>> 0;
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sign = '-';
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}
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var result = '';
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var carry;
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var t;
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var digits;
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var pad;
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var l;
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var i;
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{
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carry = high % BASE;
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high = high / BASE >>> 0;
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t = 0x100000000 * carry + low;
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low = t / BASE >>> 0;
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digits = '' + (t - BASE * low);
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if (low === 0 && high === 0) {
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return sign + digits + result;
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}
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pad = '';
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l = 6 - digits.length;
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for (i = 0; i < l; i++) {
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pad += '0';
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}
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result = pad + digits + result;
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}
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{
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carry = high % BASE;
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high = high / BASE >>> 0;
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t = 0x100000000 * carry + low;
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low = t / BASE >>> 0;
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digits = '' + (t - BASE * low);
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if (low === 0 && high === 0) {
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return sign + digits + result;
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}
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pad = '';
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l = 6 - digits.length;
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for (i = 0; i < l; i++) {
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pad += '0';
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}
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result = pad + digits + result;
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}
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{
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carry = high % BASE;
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high = high / BASE >>> 0;
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t = 0x100000000 * carry + low;
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low = t / BASE >>> 0;
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digits = '' + (t - BASE * low);
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if (low === 0 && high === 0) {
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return sign + digits + result;
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}
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pad = '';
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l = 6 - digits.length;
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for (i = 0; i < l; i++) {
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pad += '0';
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}
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result = pad + digits + result;
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}
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{
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carry = high % BASE;
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t = 0x100000000 * carry + low;
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digits = '' + t % BASE;
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return sign + digits + result;
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}
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}
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module.exports = readInt8;
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