vipunen/patched_sdk/lib/io/io_service.dart

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of dart.io;

// This list must be kept in sync with the list in runtime/bin/io_service.h
const int _FILE_EXISTS = 0;
const int _FILE_CREATE = 1;
const int _FILE_DELETE = 2;
const int _FILE_RENAME = 3;
const int _FILE_COPY = 4;
const int _FILE_OPEN = 5;
const int _FILE_RESOLVE_SYMBOLIC_LINKS = 6;
const int _FILE_CLOSE = 7;
const int _FILE_POSITION = 8;
const int _FILE_SET_POSITION = 9;
const int _FILE_TRUNCATE = 10;
const int _FILE_LENGTH = 11;
const int _FILE_LENGTH_FROM_PATH = 12;
const int _FILE_LAST_ACCESSED = 13;
const int _FILE_SET_LAST_ACCESSED = 14;
const int _FILE_LAST_MODIFIED = 15;
const int _FILE_SET_LAST_MODIFIED = 16;
const int _FILE_FLUSH = 17;
const int _FILE_READ_BYTE = 18;
const int _FILE_WRITE_BYTE = 19;
const int _FILE_READ = 20;
const int _FILE_READ_INTO = 21;
const int _FILE_WRITE_FROM = 22;
const int _FILE_CREATE_LINK = 23;
const int _FILE_DELETE_LINK = 24;
const int _FILE_RENAME_LINK = 25;
const int _FILE_LINK_TARGET = 26;
const int _FILE_TYPE = 27;
const int _FILE_IDENTICAL = 28;
const int _FILE_STAT = 29;
const int _FILE_LOCK = 30;
const int _SOCKET_LOOKUP = 31;
const int _SOCKET_LIST_INTERFACES = 32;
const int _SOCKET_REVERSE_LOOKUP = 33;
const int _DIRECTORY_CREATE = 34;
const int _DIRECTORY_DELETE = 35;
const int _DIRECTORY_EXISTS = 36;
const int _DIRECTORY_CREATE_TEMP = 37;
const int _DIRECTORY_LIST_START = 38;
const int _DIRECTORY_LIST_NEXT = 39;
const int _DIRECTORY_LIST_STOP = 40;
const int _DIRECTORY_RENAME = 41;
const int _SSL_PROCESS_FILTER = 42;

class _IOService {
  static Future<Object> _dispatch(int request, List<Object> data) {
    int id;
    do {
      id = _getNextId();
    } while (_messageMap.containsKey(id));
    int index = id % _SERVICE_PORT_COUNT;
    _initialize(index);
    var completer = new Completer<Object>();
    _messageMap[id] = completer;
    try {
      _servicePort[index].send([id, _replyToPort, request, data]);
    } catch (error) {
      _messageMap.remove(id).complete(error);
      if (_messageMap.length == 0) {
        _finalize();
      }
    }
    return completer.future;
  }

  static const int _SERVICE_PORT_COUNT = 32;

  static List<SendPort> _servicePort = new List<SendPort>(_SERVICE_PORT_COUNT);

  static RawReceivePort _receivePort;

  static SendPort _replyToPort;

  static Map<int, Completer<Object> > _messageMap = {};

  static int _id = 0;

  static void _initialize(int index) {
    if (_servicePort[index] == null) {
      _servicePort[index] = _newServicePort();
    }
    if (_receivePort == null) {
      _receivePort = new RawReceivePort();
      _replyToPort = _receivePort.sendPort;
      _receivePort.handler = (data) {
        assert(data is List);
        assert(data.length == 2);
        _messageMap.remove(data[0] as int).complete(data[1]);
        if (_messageMap.length == 0) {
          _finalize();
        }
      };
    }
  }

  static void _finalize() {
    _id = 0;
    _receivePort.close();
    _receivePort = null;
  }

  static int _getNextId() {
    if (_id == 0x7FFFFFFF) _id = 0;
    return _id++;
  }

  static SendPort _newServicePort() native "IOService_NewServicePort";
}