directory_manager.h revision 72a454cd3513ac24fbdd0e0cb9ad70b86a99b801 
1// Copyright (c) 2009 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4//
5// This used to do a lot of TLS-based management of multiple Directory objects.
6// We now can access Directory objects from any thread for general purpose
7// operations and we only ever have one Directory, so this class isn't doing
8// anything too fancy besides keeping calling and access conventions the same
9// for now.
10// TODO(timsteele): We can probably nuke this entire class and use raw
11// Directory objects everywhere.
12#ifndef CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_
13#define CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_
14#pragma once
15
16#include <string>
17#include <vector>
18
19#include "base/basictypes.h"
20#include "base/file_path.h"
21#include "base/synchronization/lock.h"
22#include "chrome/browser/sync/syncable/dir_open_result.h"
23#include "chrome/browser/sync/syncable/path_name_cmp.h"
24#include "chrome/browser/sync/syncable/syncable.h"
25#include "chrome/browser/sync/util/cryptographer.h"
26#include "chrome/common/deprecated/event_sys.h"
27
28namespace sync_api { class BaseTransaction; }
29
30namespace syncable {
31
32struct DirectoryManagerEvent {
33  enum {
34    CLOSED,
35    CLOSED_ALL,
36    SHUTDOWN,
37  } what_happened;
38  std::string dirname;
39  typedef DirectoryManagerEvent EventType;
40  static inline bool IsChannelShutdownEvent(const EventType& event) {
41    return SHUTDOWN == event.what_happened;
42  }
43};
44
45DirectoryManagerEvent DirectoryManagerShutdownEvent();
46
47class DirectoryManager {
48 public:
49  typedef EventChannel<DirectoryManagerEvent> Channel;
50
51  // root_path specifies where db is stored.
52  explicit DirectoryManager(const FilePath& root_path);
53  virtual ~DirectoryManager();
54
55  static const FilePath GetSyncDataDatabaseFilename();
56  const FilePath GetSyncDataDatabasePath() const;
57
58  // Opens a directory.  Returns false on error.
59  // Name parameter is the the user's login,
60  // MUST already have been converted to a common case.
61  bool Open(const std::string& name);
62
63  // Marks a directory as closed.  It might take a while until all the
64  // file handles and resources are freed by other threads.
65  void Close(const std::string& name);
66
67  // Should be called at App exit.
68  void FinalSaveChangesForAll();
69
70  // Gets the list of currently open directory names.
71  typedef std::vector<std::string> DirNames;
72  void GetOpenDirectories(DirNames* result);
73
74  Channel* channel() const { return channel_; }
75
76  browser_sync::Cryptographer* cryptographer() const {
77    return cryptographer_.get();
78  }
79
80 protected:
81  DirOpenResult OpenImpl(const std::string& name, const FilePath& path,
82                         bool* was_open);
83
84  // Helpers for friend class ScopedDirLookup:
85  friend class ScopedDirLookup;
86
87  const FilePath root_path_;
88
89  // protects managed_directory_
90  base::Lock lock_;
91  Directory* managed_directory_;
92
93  Channel* const channel_;
94
95  scoped_ptr<browser_sync::Cryptographer> cryptographer_;
96
97 private:
98  DISALLOW_COPY_AND_ASSIGN(DirectoryManager);
99};
100
101
102class ScopedDirLookup {
103 public:
104  ScopedDirLookup(DirectoryManager* dirman, const std::string& name);
105  ~ScopedDirLookup();
106
107  inline bool good() {
108    good_checked_ = true;
109    return good_;
110  }
111  Directory* operator -> () const;
112  operator Directory* () const;
113
114 protected:  // Don't allow creation on heap, except by sync API wrapper.
115  friend class sync_api::BaseTransaction;
116  void* operator new(size_t size) { return (::operator new)(size); }
117
118  Directory* dir_;
119  bool good_;
120  // Ensure that the programmer checks good before using the ScopedDirLookup.
121  // This member should can be removed if it ever shows up in profiling
122  bool good_checked_;
123  DirectoryManager* const dirman_;
124};
125
126}  // namespace syncable
127
128#endif  // CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_
129