1 /*

     2 * Copyright (c) 2005-2006 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Header for CIRDiskSpaceSession

    15 *

    16 */

    17 

    18 #ifndef C_IRDISKSPACESESSION_H

    19 #define C_IRDISKSPACESESSION_H

    20 

    21 #include <e32base.h>

    22 #include <f32file.h>

    23 

    24 class MIRDiskSpaceWatcherObserver;

    25 

    26 /**

    27  * Defines disk space observer. 

    28  *

    29  * Observers defined disk and notifies observer if disk space drops below

    30  * certain level.

    31  */

    32 NONSHARABLE_CLASS( CIRDiskSpaceSession ) : public CActive

    33     {

    34 

    35 public:

    36 

    37     /**

    38      * Static constructor 

    39      *

    40      * @param aDiskSpaceSessionObserver Observer who is interested if disk 

    41      * space drops below certain level.

    42      * @param aDriveNumber drive to observe

    43      * @param aCriticalLevel critical disk space level in bytes. If disk 

    44      * space falls below this observer is notified.

    45      */

    46     static CIRDiskSpaceSession* NewL(MIRDiskSpaceWatcherObserver& 

    47 							         aDiskSpaceSessionObserver, 

    48 							         const TDriveNumber& aDriveNumber, 

    49 							         const TInt64& aCriticalLevel,

    50 							         RFs& aFs );

    51 

    52     /**

    53      * Destructor

    54      */

    55     ~CIRDiskSpaceSession();

    56             

    57     /**

    58      * Tells observed drive.

    59      *

    60      * @return Drive number which is been observed by this session.

    61      */

    62     TDriveNumber DriveNumber();

    63         

    64     /**

    65      * Sets observer count

    66      *

    67      * @param aObserverCount observer count

    68      */

    69     void SetObserverCount( TInt aObserverCount );

    70 

    71     /**

    72      * Returns observer count

    73      *

    74      * @return observer count

    75      */    

    76     TInt ObserverCount();

    77     

    78     /**

    79      * IsBelowCriticalLevel Returns whether or disk defined by parameter 

    80      * contains less than the critical level free disk space.

    81      *

    82      * @param aDriveNumber drive which space is checked

    83      * @return ETrue if there is less free disk space than the critical 

    84      * level, otherwise EFalse.

    85      */

    86     TBool IsBelowCriticalLevel( const TDriveNumber& aDriveNumber ) const;

    87    

    88 protected:

    89 

    90     // from base class CActive

    91     /**

    92      * From CActive 

    93      * 

    94      * @see CActive::DoCancel()

    95      */

    96     void DoCancel();

    97 

    98     /**

    99      * From CActive 

   100      *

   101      * Invoked when the observed disk's free disk space has run 

   102      * below the supplied critical level.

   103      * Notifies the observer and regenerates the request to RFs' 

   104      * NotifyDiskSpace.

   105      * @see CActive::RunL()

   106      */

   107     void RunL();

   108 

   109 private:

   110 

   111     /**

   112      * C++ default constructor. Sets references.

   113      *

   114      * @param aDiskSpaceSessionObserver Observer who is interested if disk 

   115      * space drops below certain level.

   116      * @param aDriveNumber drive to observe

   117      * @param aCriticalLevel critical disk space level in bytes. If disk 

   118      * space falls below this observer is notified.     

   119      */

   120     CIRDiskSpaceSession(MIRDiskSpaceWatcherObserver& 

   121 				        aDiskSpaceSessionObserver, 

   122 				        const TDriveNumber& aDriveNumber, 

   123 				        const TInt64& aCriticalLevel,

   124 				        RFs& aFs );

   125 

   126     /**

   127      * Second phase constructor

   128      */

   129     void ConstructL();

   130 

   131 private: 

   132 

   133 	/** 

   134 	 * The observer to be notified when critical disk space limit is reached. 

   135 	 */

   136     MIRDiskSpaceWatcherObserver& iObserver;

   137 

   138     /** 

   139      * Drive to be observed. 

   140      */

   141     const TDriveNumber iDriveNumber;

   142 

   143     /** 

   144      * Critical disk space level. 

   145      */

   146     const TInt64 iCriticalLevel;

   147 

   148     /** 

   149      * Handle to the file system. 

   150      */

   151     RFs& iFs;

   152 

   153     /** 

   154      * Number of observers of this drive. When observer count drops to 

   155      * zero drive observation can be stopped.

   156      */

   157     TInt iObserverCount;

   158 

   159     };

   160 

   161 

   162 #endif // C_IRDISKSPACESESSION_H