chrome/browser/storage_monitor/mtab_watcher_linux.h

   1 // Copyright (c) 2013 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 // MtabWatcherLinux listens for mount point changes from a mtab file and
   6 // notifies a StorageMonitorLinux about them.
   7 // MtabWatcherLinux lives on the FILE thread.
   8
   9 #ifndef CHROME_BROWSER_STORAGE_MONITOR_MTAB_WATCHER_LINUX_H_
  10 #define CHROME_BROWSER_STORAGE_MONITOR_MTAB_WATCHER_LINUX_H_
  11
  12 #if defined(OS_CHROMEOS)
  13 #error "ChromeOS does not use MtabWatcherLinux."
  14 #endif
  15
  16 #include <map>
  17
  18 #include "base/basictypes.h"
  19 #include "base/files/file_path.h"
  20 #include "base/files/file_path_watcher.h"
  21 #include "base/memory/weak_ptr.h"
  22
  23 class MtabWatcherLinux {
  24  public:
  25   // (mount point, mount device)
  26   // A mapping from mount point to mount device, as extracted from the mtab
  27   // file.
  28   typedef std::map<base::FilePath, base::FilePath> MountPointDeviceMap;
  29
  30   class Delegate {
  31    public:
  32     virtual ~Delegate() {}
  33
  34     // Parses |new_mtab| and find all changes. Called on the UI thread.
  35     virtual void UpdateMtab(const MountPointDeviceMap& new_mtab) = 0;
  36   };
  37
  38   MtabWatcherLinux(const base::FilePath& mtab_path,
  39                    base::WeakPtr<Delegate> delegate);
  40   ~MtabWatcherLinux();
  41
  42  private:
  43   // Reads mtab file entries into |mtab|.
  44   void ReadMtab() const;
  45
  46   // Called when |mtab_path_| changes.
  47   void OnFilePathChanged(const base::FilePath& path, bool error);
  48
  49   // Mtab file that lists the mount points.
  50   const base::FilePath mtab_path_;
  51
  52   // Watcher for |mtab_path_|.
  53   base::FilePathWatcher file_watcher_;
  54
  55   base::WeakPtr<Delegate> delegate_;
  56
  57   base::WeakPtrFactory<MtabWatcherLinux> weak_ptr_factory_;
  58
  59   DISALLOW_COPY_AND_ASSIGN(MtabWatcherLinux);
  60 };
  61
  62 #endif  // CHROME_BROWSER_STORAGE_MONITOR_MTAB_WATCHER_LINUX_H_