View source for Jagex Store

This format is functionally the same as [[Old Engine/File Store|File Store]], but uses more indices to separate file types. You can get the number of indices to read from by taking the length of idx255 and dividing it by 6 (each idx255 entry is its own file). Reading works the same way (520 byte sectors) except there is now a 9-byte header included as part of each entry.

The 9-byte header has the compression type (1 byte), file size (4 bytes), and uncompressed size (4 bytes). A compression type of 1 uses BZip2 and you have to prepend the magic number. A compression type of 2 uses gzip.

===File Types===
dat = data

dat0 = sd client in pack200 format (minus gzip header `1f 8b`)

dat1 = sd client in packclass format

dat2 = data

dat3 = hd client in pack200 format

dat4 = hd client in packclass format

dat5 = jogl/jaggl library in pack200 format

dat6 = jogl/jaggl library in packclass format

idx* = file index

===Reading===
<syntaxhighlight lang="js">
const BZIP2_HEADER = new Uint8Array([0x42, 0x5A, 0x68, 0x31]);

// Backwards compatible with 234-402 caches (legacy)
export class JagexStore {
    constructor(path) {
        this.legacy = false;

        if (fs.existsSync(`${path}/main_file_cache.dat`)) {
            this.legacy = true;
        }

        if (!this.legacy) {
            this.dat2 = new RandomAccessFile(`${path}/main_file_cache.dat2`, false);
            this.idx255 = new RandomAccessFile(`${path}/main_file_cache.idx255`, false);

            let idxCount = this.idx255.length / 6;
            for (let i = 0; i < idxCount; ++i) {
                this[`idx${i}`] = new RandomAccessFile(`${path}/main_file_cache.idx${i}`, false);
            }

            this.index_offset = 0;
        } else {
            this.dat2 = new RandomAccessFile(`${path}/main_file_cache.dat`, false);

            for (let i = 0; i < 5; ++i) {
                this[`idx${i}`] = new RandomAccessFile(`${path}/main_file_cache.idx${i}`, false);
            }

            this.index_offset = 1;
        }
    }

    read(index, entry, extract = false) {
        if (!this[`idx${index}`]) {
            return null;
        }

        let buffer = this[`idx${index}`].front().seek(entry * 6).read(6);
        if (!buffer.available) {
            return null;
        }

        let length = buffer.readSWord();
        if (length === 0 || length > this.dat2.length) {
            return null;
        }

        let data = new ByteBuffer(new Uint8Array(length), false);
        let nextSector = buffer.readSWord();

        if (nextSector * 520 > this.dat2.length) {
            return null;
        }

        let part = 0;
        while (data.available && nextSector !== 0) {
            let sector = this.dat2.front().seek(nextSector * 520).read(520);

            let bytes = data.available;
            if (bytes > 512) {
                bytes = 512;
            }

            let currentFile = sector.readWord();
            if (currentFile !== entry) {
                return null;
            }

            let currentPart = sector.readWord();
            if (currentPart !== part) {
                return null;
            }

            nextSector = sector.readSWord();
            if (nextSector * 520 > this.dat2.length) {
                return null;
            }

            let currentIndex = sector.readByte();
            if (currentIndex - this.index_offset !== index) {
                return null;
            }

            data.write(sector.read(bytes));
            part++;
        }
        data.front();

        let file = { compression: 0, size: 0, decompressedSize: 0, data };

        if (!this.legacy) {
            file.compression = data.readByte(),
            file.size = data.readDWord(),
            file.decompressedSize = data.readDWord(),
            file.data = data.read()
        } else {
            file.compression = index === 0 ? 1 : 2;
            file.size = file.data.length;
        }

        if (extract) {
            if (file.compression === 1 && this.legacy) {
                file = new FileArchive(file.data);
            } else if (file.compression === 1) {
                file.data = bz2.decompress(file.data.prepend(BZIP2_HEADER).raw);
            } else if (file.compression === 2) {
                file.data = new Uint8Array(zlib.gunzipSync(file.data.raw));
                if (this.legacy) {
                    file.decompressedSize = file.data.length;
                }
            }
        }

        return file;
    }
}
</syntaxhighlight>