A short script that looks through the high work memory for sega saturn to look for possible xp data structs

find_xpdata.js

"use strict";

const fs = require("fs");
const fp = fs.readFileSync("hwram.bin");

const ptr_keys = [
        "vlist_offset",
        "plist_offset",
        "attr_offset",
        "vntbl"
];

let i = 0;

do {

        let struct = {
                offset : i,
                vlist_offset : fp.readUInt32BE(i + 0),
                vlist_count :  fp.readUInt32BE(i + 4),
                plist_offset : fp.readUInt32BE(i + 8),
                plist_count :  fp.readUInt32BE(i + 12),
                attr_offset :  fp.readUInt32BE(i + 16),
                vntbl :        fp.readUInt32BE(i + 20)
        };

        let isStruct = true;
        ptr_keys.forEach(function(key) {
                if((struct[key] % 4) !== 0) {
                        isStruct = false;
                }

                if((struct[key] & 0x06000000) !== 0x06000000) {
                        isStruct = false;
                }
        });

        for(let key in struct) {
                if(struct[key] === 0) {
                        isStruct = false;
                }
        }

        if(struct.vlist_count > 0xffff) {
                isStruct = false;
        }

        if(struct.plist_count > 0xffff) {
                isStruct = false;
        }

        if(!isStruct) {
                i += 4;
                continue;
        }


        formatHex(struct);
        console.log(struct);
        i += 0x18;

} while(i < fp.length - 0x18);

function formatHex(obj) {

        for(let key in obj) {

                let num = obj[key].toString(16);
                while(num.length < 6) {
                        num = "0" + num;
                }

                obj[key] = "0x" + num;

        }

}