components/storage_monitor/volume_mount_watcher_win.h

   1 // Copyright 2014 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 #ifndef COMPONENTS_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_
   6 #define COMPONENTS_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "base/basictypes.h"
  14 #include "base/callback.h"
  15 #include "base/files/file_path.h"
  16 #include "base/memory/weak_ptr.h"
  17 #include "base/sequenced_task_runner.h"
  18 #include "base/strings/string16.h"
  19 #include "base/threading/sequenced_worker_pool.h"
  20 #include "components/storage_monitor/storage_info.h"
  21 #include "components/storage_monitor/storage_monitor.h"
  22
  23 namespace storage_monitor {
  24
  25 class TestVolumeMountWatcherWin;
  26
  27 // This class watches the volume mount points and sends notifications to
  28 // StorageMonitor about the device attach/detach events.
  29 // This is a singleton class instantiated by StorageMonitorWin.
  30 class VolumeMountWatcherWin {
  31  public:
  32   VolumeMountWatcherWin();
  33   virtual ~VolumeMountWatcherWin();
  34
  35   // Returns the volume file path of the drive specified by the |drive_number|.
  36   // |drive_number| inputs of 0 - 25 are valid. Returns an empty file path if
  37   // the |drive_number| is invalid.
  38   static base::FilePath DriveNumberToFilePath(int drive_number);
  39
  40   void Init();
  41
  42   // Gets the information about the device mounted at |device_path|. On success,
  43   // returns true and fills in |info|.
  44   // Can block during startup while device info is still loading.
  45   bool GetDeviceInfo(const base::FilePath& device_path,
  46                      StorageInfo* info) const;
  47
  48   // Processes DEV_BROADCAST_VOLUME messages and triggers a
  49   // notification if appropriate.
  50   void OnWindowMessage(UINT event_type, LPARAM data);
  51
  52   // Processes SHCNE_MEDIAINSERTED (and REMOVED).
  53   void OnMediaChange(WPARAM wparam, LPARAM lparam);
  54
  55   // Set the volume notifications object to be used when new
  56   // removable volumes are found.
  57   void SetNotifications(StorageMonitor::Receiver* notifications);
  58
  59   void EjectDevice(const std::string& device_id,
  60                    base::Callback<void(StorageMonitor::EjectStatus)> callback);
  61
  62  protected:
  63   typedef base::Callback<bool(const base::FilePath&,
  64                               StorageInfo*)> GetDeviceDetailsCallbackType;
  65
  66   typedef base::Callback<std::vector<base::FilePath>(void)>
  67       GetAttachedDevicesCallbackType;
  68
  69   // Handles mass storage device attach event on UI thread.
  70   void HandleDeviceAttachEventOnUIThread(
  71       const base::FilePath& device_path,
  72       const StorageInfo& info);
  73
  74   // Handles mass storage device detach event on UI thread.
  75   void HandleDeviceDetachEventOnUIThread(const base::string16& device_location);
  76
  77   // UI thread delegate to set up adding storage devices.
  78   void AddDevicesOnUIThread(std::vector<base::FilePath> removable_devices);
  79
  80   // Runs |get_device_details_callback| for |device_path| on a worker thread.
  81   // |volume_watcher| points back to the VolumeMountWatcherWin that called it.
  82   static void RetrieveInfoForDeviceAndAdd(
  83       const base::FilePath& device_path,
  84       const GetDeviceDetailsCallbackType& get_device_details_callback,
  85       base::WeakPtr<VolumeMountWatcherWin> volume_watcher);
  86
  87   // Mark that a device we started a metadata check for has completed.
  88   virtual void DeviceCheckComplete(const base::FilePath& device_path);
  89
  90   virtual GetAttachedDevicesCallbackType GetAttachedDevicesCallback() const;
  91   virtual GetDeviceDetailsCallbackType GetDeviceDetailsCallback() const;
  92
  93   // Worker pool used to collect device information. Used because some
  94   // devices freeze workers trying to get device info, resulting in
  95   // shutdown hangs.
  96   scoped_refptr<base::SequencedWorkerPool> device_info_worker_pool_;
  97   scoped_refptr<base::SequencedTaskRunner> task_runner_;
  98
  99  private:
 100   friend class TestVolumeMountWatcherWin;
 101
 102   // Key: Mass storage device mount point.
 103   // Value: Mass storage device metadata.
 104   typedef std::map<base::FilePath, StorageInfo> MountPointDeviceMetadataMap;
 105
 106   // Maintain a set of device attribute check calls in-flight. Only accessed
 107   // on the UI thread. This is to try and prevent the same device from
 108   // occupying our worker pool in case of windows API call hangs.
 109   std::set<base::FilePath> pending_device_checks_;
 110
 111   // A map from device mount point to device metadata. Only accessed on the UI
 112   // thread.
 113   MountPointDeviceMetadataMap device_metadata_;
 114
 115   // The notifications object to use to signal newly attached volumes. Only
 116   // removable devices will be notified.
 117   StorageMonitor::Receiver* notifications_;
 118
 119   base::WeakPtrFactory<VolumeMountWatcherWin> weak_factory_;
 120
 121   DISALLOW_COPY_AND_ASSIGN(VolumeMountWatcherWin);
 122 };
 123
 124 }  // namespace storage_monitor
 125
 126 #endif  // COMPONENTS_STORAGE_MONITOR_VOLUME_MOUNT_WATCHER_WIN_H_