tar-lister.odin

read_tar :: proc(reader: ^io.Reader) {
    Posix_Ustar_Header :: struct #packed {
    	name: [100]u8,
    	mode: [8]u8,
    	uid: [8]u8,
    	gid: [8]u8,
    	size: [12]u8,
    	mtime: [12]u8,
    	checksum: [8]u8,
    	typeflag: u8,
    	linkname: [100]u8,
    	magic: [6]u8,
    	version: [2]u8,
    	uname: [32]u8,
    	gname: [32]u8,
    	devmajor: [8]u8,
    	devminor: [8]u8,
    	prefix: [155]u8,
    	pad: [12]u8,
    };
    USTAR_MAGIC := [?]byte{'u', 's', 't', 'a', 'r', 0};

    loop:
    for {
        // io.read_typeid is confusingly named, this read the struct Posix_Ustar_Header from the file, not an actual `typeid`
        header, err := io.read_typeid(reader, Posix_Ustar_Header);
        if header.magic != USTAR_MAGIC {
            break loop;
        }

        size := parse_i64(string(header.size[:len(header.size)-1]), 8);
        fmt.printf("name: %s, size: %v\n", cstring(&header.name[0]), size);

        if size == 0 do continue;

        read_size := size;
        if read_size % 512 != 0 {
            read_size += (512 - (size % 512));
        }
        data := make([]u8, read_size);
        io.read(reader, data);
        delete(data);
    }
}