Function atomicWriteFileSync

server/index.js:29–55

(filePath, data, options = 'utf8')

// Atomic file write: write to temp file then rename to prevent corruption
const atomicWriteFileSync = (filePath, data, options = 'utf8') => {
    const dir = path.dirname(filePath);
    if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true });
    const tempPath = path.join(dir, `.${path.basename(filePath)}.${crypto.randomBytes(6).toString('hex')}.tmp`);
    try {
        fs.writeFileSync(tempPath, data, options);
        // Retry rename for Windows file locking issues
        let retries = 5;
        while (retries > 0) {
            try {
                fs.renameSync(tempPath, filePath);
                break;
            } catch (e) {
                if (retries === 1) throw e;
                retries--;
                // Synchronous delay
                const start = Date.now();
                while (Date.now() - start < 50) {} 
            }
        }
    } catch (err) {
        if (fs.existsSync(tempPath)) {
            try { fs.unlinkSync(tempPath); } catch (e) {}
        }
        throw err;
    }
};

const app = express();
const DEFAULT_PORT = 1920;