Function start

src/worker.js:67–1262

()

let instance = null;

async function start() {
    const wasmBuffer = fs.readFileSync(wasmPath);
    
    // Build WASI args based on options
    // The emulator supports -net socket for networking via WASI sockets
    const wasiArgs = ['agentvm'];
    if (network) {
        wasiArgs.push('-net', 'socket');
        if (mac) {
            wasiArgs.push('-mac', mac);
        }
    }
    
    // parentPort.postMessage({ type: 'debug', msg: `WASI args: ${wasiArgs.join(' ')}` });
    
    // Store preopens for our custom path_open implementation
    const preopenPaths = mounts || {};
    // Map wasi fd to host path (fd 3 onwards)
    const fdToHostPath = new Map();
    let preopen_fd = 3;
    for (const [wasiPath, hostPath] of Object.entries(preopenPaths)) {
        fdToHostPath.set(preopen_fd, { wasiPath, hostPath: require('path').resolve(hostPath) });
        preopen_fd++;
    }
    
    const wasi = new WASI({
        version: 'preview1',
        args: wasiArgs,
        env: { 'TERM': 'xterm-256color', 'LISTEN_FDS': '1' },
        preopens: preopenPaths 
    });

    const wasiImport = wasi.wasiImport;
    
    // Track next available fd for our fake duplicates and custom file handles
    let nextFakeFd = 100; // Start high to avoid conflicts
    const fakeFdMap = new Map(); // fake fd -> original fd (for directory duplicates)
    const customFdHandles = new Map(); // fd -> {type: 'file', handle: fs.FileHandle, hostPath: string}
    
    // Fix for path_open: Node.js WASI has multiple bugs with preopened directories
    // We implement our own file opening for preopened directory contents
    const origPathOpen = wasiImport.path_open;
    wasiImport.path_open = (fd, dirflags, path_ptr, path_len, oflags, fs_rights_base, fs_rights_inheriting, fdflags, opened_fd_ptr) => {
        // Get the path string
        let pathStr = '';
        if (instance) {
            const mem = new Uint8Array(instance.exports.memory.buffer);
            const pathBytes = mem.slice(path_ptr, path_ptr + path_len);
            pathStr = new TextDecoder().decode(pathBytes);
        }
        
        // Resolve fake fd to real fd for the base directory
        let actualFd = fakeFdMap.has(fd) ? fakeFdMap.get(fd) : fd;
        
        // Check if this is a preopened directory OR one of our custom directory handles
        let preopenInfo = fdToHostPath.get(actualFd);
        
        // Also check if fd is one of our custom directory handles