chrome/browser/storage_monitor/storage_monitor_linux.h

   1 // Copyright (c) 2012 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 // StorageMonitorLinux processes mount point change events, notifies listeners
   6 // about the addition and deletion of media devices, and answers queries about
   7 // mounted devices.
   8 // StorageMonitorLinux lives on the UI thread, and uses a MtabWatcherLinux on
   9 // the FILE thread to get mount point change events.
  10
  11 #ifndef CHROME_BROWSER_STORAGE_MONITOR_STORAGE_MONITOR_LINUX_H_
  12 #define CHROME_BROWSER_STORAGE_MONITOR_STORAGE_MONITOR_LINUX_H_
  13
  14 #if defined(OS_CHROMEOS)
  15 #error "Use the ChromeOS-specific implementation instead."
  16 #endif
  17
  18 #include <map>
  19 #include <string>
  20
  21 #include "base/basictypes.h"
  22 #include "base/compiler_specific.h"
  23 #include "base/files/file_path.h"
  24 #include "base/files/file_path_watcher.h"
  25 #include "base/memory/scoped_ptr.h"
  26 #include "base/memory/weak_ptr.h"
  27 #include "chrome/browser/storage_monitor/mtab_watcher_linux.h"
  28 #include "chrome/browser/storage_monitor/storage_monitor.h"
  29 #include "content/public/browser/browser_thread.h"
  30
  31 class MediaTransferProtocolDeviceObserverLinux;
  32
  33 class StorageMonitorLinux : public StorageMonitor,
  34                             public MtabWatcherLinux::Delegate {
  35  public:
  36   // Should only be called by browser start up code.
  37   // Use StorageMonitor::GetInstance() instead.
  38   // |mtab_file_path| is the path to a mtab file to watch for mount points.
  39   explicit StorageMonitorLinux(const base::FilePath& mtab_file_path);
  40   virtual ~StorageMonitorLinux();
  41
  42   // Must be called for StorageMonitorLinux to work.
  43   virtual void Init() OVERRIDE;
  44
  45  protected:
  46   // Gets device information given a |device_path| and |mount_point|.
  47   typedef base::Callback<scoped_ptr<StorageInfo>(
  48       const base::FilePath& device_path,
  49       const base::FilePath& mount_point)> GetDeviceInfoCallback;
  50
  51   void SetGetDeviceInfoCallbackForTest(
  52       const GetDeviceInfoCallback& get_device_info_callback);
  53
  54   void SetMediaTransferProtocolManagerForTest(
  55       device::MediaTransferProtocolManager* test_manager);
  56
  57   // MtabWatcherLinux::Delegate implementation.
  58   virtual void UpdateMtab(
  59       const MtabWatcherLinux::MountPointDeviceMap& new_mtab) OVERRIDE;
  60
  61  private:
  62   // Structure to save mounted device information such as device path, unique
  63   // identifier, device name and partition size.
  64   struct MountPointInfo {
  65     base::FilePath mount_device;
  66     StorageInfo storage_info;
  67   };
  68
  69   // For use with scoped_ptr.
  70   struct MtabWatcherLinuxDeleter {
  71     void operator()(MtabWatcherLinux* mtab_watcher) {
  72       content::BrowserThread::DeleteSoon(content::BrowserThread::FILE,
  73                                          FROM_HERE, mtab_watcher);
  74     }
  75   };
  76
  77   // Mapping of mount points to MountPointInfo.
  78   typedef std::map<base::FilePath, MountPointInfo> MountMap;
  79
  80   // (mount point, priority)
  81   // For devices that are mounted to multiple mount points, this helps us track
  82   // which one we've notified system monitor about.
  83   typedef std::map<base::FilePath, bool> ReferencedMountPoint;
  84
  85   // (mount device, map of known mount points)
  86   // For each mount device, track the places it is mounted and which one (if
  87   // any) we have notified system monitor about.
  88   typedef std::map<base::FilePath, ReferencedMountPoint> MountPriorityMap;
  89
  90   // StorageMonitor implementation.
  91   virtual bool GetStorageInfoForPath(const base::FilePath& path,
  92                                      StorageInfo* device_info) const OVERRIDE;
  93   virtual void EjectDevice(const std::string& device_id,
  94                            base::Callback<void(EjectStatus)> callback) OVERRIDE;
  95   virtual device::MediaTransferProtocolManager*
  96       media_transfer_protocol_manager() OVERRIDE;
  97
  98   // Called when the MtabWatcher has been created.
  99   void OnMtabWatcherCreated(MtabWatcherLinux* watcher);
 100
 101   bool IsDeviceAlreadyMounted(const base::FilePath& mount_device) const;
 102
 103   // Assuming |mount_device| is already mounted, and it gets mounted again at
 104   // |mount_point|, update the mappings.
 105   void HandleDeviceMountedMultipleTimes(const base::FilePath& mount_device,
 106                                         const base::FilePath& mount_point);
 107
 108   // Adds |mount_device| to the mappings and notify listeners, if any.
 109   void AddNewMount(const base::FilePath& mount_device,
 110                    scoped_ptr<StorageInfo> storage_info);
 111
 112   // Mtab file that lists the mount points.
 113   const base::FilePath mtab_path_;
 114
 115   // Callback to get device information. Set this to a custom callback for
 116   // testing.
 117   GetDeviceInfoCallback get_device_info_callback_;
 118
 119   // Mapping of relevant mount points and their corresponding mount devices.
 120   // Keep in mind on Linux, a device can be mounted at multiple mount points,
 121   // and multiple devices can be mounted at a mount point.
 122   MountMap mount_info_map_;
 123
 124   // Because a device can be mounted to multiple places, we only want to
 125   // notify about one of them. If (and only if) that one is unmounted, we need
 126   // to notify about it's departure and notify about another one of it's mount
 127   // points.
 128   MountPriorityMap mount_priority_map_;
 129
 130   scoped_ptr<device::MediaTransferProtocolManager>
 131       media_transfer_protocol_manager_;
 132   scoped_ptr<MediaTransferProtocolDeviceObserverLinux>
 133       media_transfer_protocol_device_observer_;
 134
 135   scoped_ptr<MtabWatcherLinux, MtabWatcherLinuxDeleter> mtab_watcher_;
 136
 137   base::WeakPtrFactory<StorageMonitorLinux> weak_ptr_factory_;
 138
 139   DISALLOW_COPY_AND_ASSIGN(StorageMonitorLinux);
 140 };
 141
 142 #endif  // CHROME_BROWSER_STORAGE_MONITOR_STORAGE_MONITOR_LINUX_H_