tools/shell/lib/repl_init.js

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import * as li_internal from 'li_internal';

(function (global) {
  var readBuffer;
  var repl;
  var stdinFd;

  function InitRepl() {
    repl = li_internal.createRepl();
    stdinFd = std.in.fileno();

    global['repl_init'] = {
      repl,
    };

    // a handler on std.in
    readBuffer = new Uint8Array(64);
    os.setReadHandler(stdinFd, readHandler);
  }

  function readHandler() {
    var l = os.read(stdinFd, readBuffer.buffer, 0, readBuffer.length);
    var exitShell = li_internal.onInput(repl, readBuffer.buffer, l);
    if (exitShell) {
      std.out.flush();
      os.setReadHandler(stdinFd, null); //remove read handler
      li_internal.closeRepl(repl);
    }
    std.gc();//running it every now and then
  }

  InitRepl();

})(globalThis);