| name | rom-scanner-hashing |
| description | Use this skill when implementing ROM scanning and CRC hashing logic for matching local files against the GameBase64 database. |
| version | 1.0.0 |
| author | 64Box |
| tags | ["rom-scanner","crc32","rust","tauri","zip"] |
ROM Scanner & CRC Hashing
When to Use This Skill
- When writing Rust backend commands to scan a user's local directories for games.
- When implementing CRC32 hashing to match local files against the
Games database.
- When linking discovered
.zip, .d64, .t64, .tap, or .crt files to metadata.
1. Memory Management & Streaming
Never load entire files or large file sets into RAM at once.
- Do not use
std::fs::read(path) or std::fs::read_to_string(path) for scanner hashing.
- Use
std::fs::File, std::io::BufReader, and crc32fast to hash uncompressed files in chunks.
use crc32fast::Hasher;
use std::fs::File;
use std::io::{BufRead, BufReader};
let file = File::open(path)?;
let mut reader = BufReader::new(file);
let mut hasher = Hasher::new();
let mut buffer = [0; 8192];
while let Ok(count) = reader.read(&mut buffer) {
if count == 0 { break; }
hasher.update(&buffer[..count]);
}
let crc = hasher.finalize();
2. Zip File Optimization
Most official GameBase64 collection files are zipped.
- Do not extract and hash the archive contents just to find CRC.
- Read CRC32 directly from the zip central directory with a crate such as
zip or async_zip.
3. Database Matching & Formatting
- Format CRC output as a padded 8-character hexadecimal string.
- Match with case-insensitive queries such as:
SELECT GA_Id, Name FROM Games WHERE CRC = ? COLLATE NOCASE
4. UI Non-Blocking & IPC Progress
- Run scanning work asynchronously with
tokio::task::spawn_blocking or tauri::async_runtime.
- Emit progress events over Tauri IPC so the frontend can keep the UI responsive.
Example event payload:
tauri::Window::emit("scan-progress", { "scanned": 1500, "total": 30000, "current_file": "Commando.zip" })
