snarkjs/src/loadsyms.js

zkSNARKs implementation in JavaScript

/*
    Copyright 2018 0KIMS association.

    This file is part of snarkJS.

    snarkJS is a 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 3 of the License, or
    (at your option) any later version.

    snarkJS 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 snarkJS. If not, see <https://www.gnu.org/licenses/>.
*/

import * as fastFile from "fastfile";

export default async function loadSymbols(symFileName) {
    const sym = {
        labelIdx2Name: [ "one" ],
        varIdx2Name: [ "one" ],
        componentIdx2Name: []
    };
    const fd = await fastFile.readExisting(symFileName);
    const buff = await fd.read(fd.totalSize);
    const symsStr = new TextDecoder("utf-8").decode(buff);
    const lines = symsStr.split("\n");
    for (let i=0; i<lines.length; i++) {
        const arr = lines[i].split(",");
        if (arr.length!=4) continue;
        if (sym.varIdx2Name[arr[1]]) {
            sym.varIdx2Name[arr[1]] += "|" + arr[3];
        } else {
            sym.varIdx2Name[arr[1]] = arr[3];
        }
        sym.labelIdx2Name[arr[0]] = arr[3];
        if (!sym.componentIdx2Name[arr[2]]) {
            sym.componentIdx2Name[arr[2]] = extractComponent(arr[3]);
        }
    }

    await fd.close();

    return sym;

    function extractComponent(name) {
        const arr = name.split(".");
        arr.pop(); // Remove the lasr element
        return arr.join(".");
    }
}