Move Index and IndexStore implementations into Engine.

pkg/analysis_server/lib/src/index/file_page_manager.dart

-// Copyright (c) 2014, 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.
-
-library index.file_page_manager;
-
-import 'dart:io';
-import 'dart:typed_data';
-
-import 'package:analysis_server/src/index/page_node_manager.dart';
-
-
-/**
- * A [PageManager] that stores pages on disk.
- */
-class FilePageManager implements PageManager {
-  final int pageSizeInBytes;
-
-  RandomAccessFile _file;
-  File _fileRef;
-  List<int> _freePagesList = new List<int>();
-  Set<int> _freePagesSet = new Set<int>();
-  int _nextPage = 0;
-
-  FilePageManager(this.pageSizeInBytes, String path) {
-    _fileRef = new File(path);
-    _file = _fileRef.openSync(mode: FileMode.WRITE);
-  }
-
-  @override
-  int alloc() {
-    if (_freePagesList.isNotEmpty) {
-      int id = _freePagesList.removeLast();
-      _freePagesSet.remove(id);
-      return id;
-    }
-    int id = _nextPage++;
-    Uint8List page = new Uint8List(pageSizeInBytes);
-    _file.setPositionSync(id * pageSizeInBytes);
-    _file.writeFromSync(page);
-    return id;
-  }
-
-  /**
-   * Closes this [FilePageManager].
-   */
-  void close() {
-    _file.closeSync();
-  }
-
-  /**
-   * Deletes the underlaying file.
-   */
-  void delete() {
-    if (_fileRef.existsSync()) {
-      _fileRef.deleteSync();
-    }
-  }
-
-  @override
-  void free(int id) {
-    if (!_freePagesSet.add(id)) {
-      throw new StateError('Page $id has been already freed.');
-    }
-    _freePagesList.add(id);
-  }
-
-  @override
-  Uint8List read(int id) {
-    Uint8List page = new Uint8List(pageSizeInBytes);
-    _file.setPositionSync(id * pageSizeInBytes);
-    int actual = 0;
-    while (actual != page.length) {
-      actual += _file.readIntoSync(page, actual);
-    }
-    return page;
-  }
-
-  @override
-  void write(int id, Uint8List page) {
-    _file.setPositionSync(id * pageSizeInBytes);
-    _file.writeFromSync(page);
-  }
-}