featuremgmt/featuremgr/inc/featurecontrol.h
changeset 0 08ec8eefde2f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/featuremgmt/featuremgr/inc/featurecontrol.h	Fri Jan 22 11:06:30 2010 +0200
@@ -0,0 +1,508 @@
+/*
+* Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+
+
+
+
+
+#ifndef FEATURECONTROL_H
+#define FEATURECONTROL_H
+
+//  INCLUDES
+#include <e32std.h>
+#include <e32svr.h>
+#include <featmgr/featurecmn.h>
+
+// FORWARD DECLARATIONS
+
+// DEFINES
+
+// CLASS DECLARATION
+
+// CONSTANTS
+
+// MACROS
+
+/**
+
+ The Feature Control API provides methods that can be used to query which
+ features are supported on the device.  The API also provides  methods to
+ get status flags that define that behaviour of the feature flag and data
+ associated with the feature.
+
+ The Feature Control API provides methods to enable and disable features at
+ runtime e.g. when new software is installed or uninstalled. The API provides
+ also methods for setting feature data, adding a new feature to the device
+ and listing all supported features on the device.
+
+ It is only possible to enable or disable a feature or set feature data
+ at runtime if that feature is modifiable (this is defined by the status
+ 32 bit word associated with the feature flag).  It is also possible to enable or
+ disable a feature UID that is not even defined in the device yet.
+ When adding a new feature to the device status flags and data of the feature
+ must be set.
+
+ The meaning of the bits of the 32-bit feature status flags are as follows:
+
+ Bit   Flag Name	    Meaning
+ - 0   Supported	    If set, feature is supported and available for use;
+                       if not, feature is not supported.
+ - 1   Upgradeable	    If set, feature is upgradeable. The feature is known to
+                       the device but it must be upgraded to enable it. If a feature
+                       is blacklisted, its upgradeable flag is unset.
+ - 2   Modifiable	    If set, the feature is modifiable and may be enabled/disabled at
+                       run-time. The initial flag values for such a feature flag are
+                       defined in a ROM image obey file.
+ - 3   Blacklisted	    If set, the feature has been blacklisted, and may not be changed
+                       at run-time. This also prevents a feature from being upgraded.
+ - 4   Uninitialised	If set, the status flag Supported is unknown at build-time and is
+                       initialised at run-time by system software. The Feature Manager
+                       will ignore the Supported flag in the file. A run-time call to
+                       RFeatureControl will be needed to set the feature's supported
+                       flag. Look ups of uninitialised features result in a KErrNotReady
+                       error code.
+ - 5   Persisted	    If set, this flag is saved to the system drive when modified
+                       preserving its value across reboots/power downs
+ - 6 ..23              Reserved for future use, always zero.
+ - 24..31 	           Reserved for internal use.
+
+ Enumeration TFeatureFlags defined in featurecmn.h should be used for
+ accessing feature status flags e.g. flags.IsSet( EFeatureUpgradeable ),
+ flags.IsSet( EFeatureModifiable ).
+
+ Feature data is 32-bit word for client read and write. Feature data can
+ contain any data that needs to be associated with the Feature Flag.
+ Feature data can only be set if the feature is modifiable or a new feature.
+
+ The use of the Feature Manager API to set the supported status of a feature,
+ it in no way means that the functionality itself is modified on the device.
+ All the corresponding DLLs, including feature functionality and resources still
+ remain on the device. To properly support runtime activation/deactivation
+ of the feature, all feature APIs need to implement runtime checking of the
+ feature status in their code.
+
+ The API consists of the RFeatureControl class which is
+ used together with feature UIDs defined in featureUIDs.h, TFeatureFlags,
+ TFeatureEntry and RFeatureUidArray defined in featurecmn.h.
+
+
+ Usage:
+
+ Before calling any other methods the client must call the Open()
+ method that connects to the Feature Manager Server.
+ When the client has finished using the RFeatureControl it should
+ disconnect using the Close() method.
+
+@publishedPartner
+@released
+*/
+NONSHARABLE_CLASS(RFeatureControl)
+    {
+    public:
+        /**
+         C++ default constructor.
+        */
+        IMPORT_C RFeatureControl();
+
+        /**
+         Connect() must be called before calling any other methods of
+         RFeatureControl.
+         It connects to the Feature Manager Server.
+         After usage Close() function must be called.
+
+         @return Error Code. One of the Symbian error codes.
+
+         @deprecated Use Open() instead.
+        */
+        IMPORT_C TInt Connect();
+
+        /**
+         Open() must be called before calling any other methods of
+         RFeatureControl.
+         After usage Close() function must be called.
+
+         @return Error Code. One of the Symbian error codes.
+        */
+        IMPORT_C TInt Open();
+
+        /**
+         Remember to call Close after using RFeatureControl.
+        */
+        IMPORT_C void Close();
+
+		/**
+         This method returns the supported status on the device of the feature
+         specified in the aFeature parameter.
+
+	     @param aFeature Feature UID.
+	     @return KFeatureSupported if the feature is supported.
+	             KFeatureUnsupported if the feature is not supported.
+	             KErrNotFound if the feature does not exist.
+	             KErrNotReady it the feature is uninitialized.
+	             Otherwise one of the Symbian error codes.
+
+
+	    */
+        IMPORT_C TInt FeatureSupported( TUid aFeature );
+
+        /**
+         This method returns the supported status on the device of the feature
+         described by the aFeature parameter.  The feature UID should be set in
+         TFeatureEntry class before the FeatureSupported method is called.  If
+         FeatureSupported returns successufully the TFeatureEntry parameter will
+         also have been populated with the feature's status flags and the data
+         word associates with the feature.
+
+	     @param aFeature A reference to a a client owned TFeatureEntry object.
+	                     Must contain UID of the queried feature.
+	                     After returning contains status flags and data of
+	                     the feature.
+	     @return KFeatureSupported if the feature is supported.
+	             KFeatureUnsupported if the feature is not supported.
+	             KErrNotFound if the feature does not exist.
+	             KErrNotReady if the feature is uninitialized.
+	             Otherwise one of the Symbian error codes.
+
+
+	    */
+        IMPORT_C TInt FeatureSupported( TFeatureEntry& aFeature );
+
+        /**
+         This method allows the user to pass an array of type TFeatureEntry
+         to Feature Manager.  In this way the user can retrieve the supported status and
+         associated information for the features whose UIDs have been set in
+         TFeatureEntry classes.  In order for the client to know whether
+         feature is just disabled or does not exist at all it must check
+         this from response feature array. If the feature exists the EFeatureSupported
+         status bit will contain the support status. If the feature does not exist
+         it will be removed from array after the query. For this reason instead of hard
+         coding array accesses for features the Find method should always
+         be used to query feature index in array after query.
+
+	     @param aFeatures A reference to a a client owned RFeatureArray array.
+	                     Must contain UIDs of the queried features.
+	     @return KErrNone if fetching of features statuses successful.
+	             KErrArgument if query made with empty array.
+	             Otherwise one of the Symbian error codes.
+
+	    */
+        IMPORT_C TInt FeaturesSupported( RFeatureArray& aFeatures );
+
+        /**
+         Enables the specified feature. WriteDeviceData capability required.
+
+         @param aFeature Feature UID.
+         @return Error Code. KErrNone if the feature was succesfully enabled.
+                             KErrAccessDenied if the feature is not modifiable.
+                             KErrPermissionDenied if a capability check fails.
+                             KErrNotFound if the feature does not exist.
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded.
+                             Otherwise one of the Symbian error codes. 
+        */
+        IMPORT_C TInt EnableFeature( TUid aFeature );
+
+        /**
+         Disables the specified feature. WriteDeviceData capability required.
+
+         @param aFeature Feature UID.
+         @return Error Code. KErrNone if the feature was succesfully disabled.
+                             KErrAccessDenied if the feature is not modifiable.
+                             KErrPermissionDenied if a capability check fails.
+                             KErrNotFound if the feature does not exist.
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded.
+                             Otherwise one of the Symbian error codes. 
+        */
+        IMPORT_C TInt DisableFeature( TUid aFeature );
+
+        /**
+         Enables or disables the specified feature and sets feature data.
+         WriteDeviceData capability required.
+
+         @param aFeature Feature UID.
+         @param aEnabled ETrue if enabling the feature, EFalse if disabling.
+         @param aData Feature data.
+         @return Error Code. KErrNone if the feature was succesfully enabled.
+                             KErrAccessDenied if the feature is not modifiable.
+                             KErrPermissionDenied if a capability check fails.
+                             KErrNotFound if the feature does not exist.
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded. 
+                             Otherwise one of the Symbian error codes. 
+        */
+        IMPORT_C TInt SetFeature( TUid aFeature, TBool aEnabled, TUint32 aData );
+
+        /**
+         Sets feature data. WriteDeviceData capability required.
+
+         @param aFeature Feature UID.
+         @param aData Feature data.
+         @return Error Code. KErrNone if the feature data was succesfully set.
+                             KErrAccessDenied if the feature is not modifiable.
+                             KErrPermissionDenied if a capability check fails.
+                             KErrNotFound if the feature does not exist. 
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded.
+                             Otherwise one of the Symbian error codes. 
+        */
+        IMPORT_C TInt SetFeature( TUid aFeature, TUint32 aData );
+
+        /**
+         Adds a new feature and sets status flags and data of the feature.
+         Note: When adding a new feature to the device status flags and
+         data of the feature must be set. WriteDeviceData capability required.
+
+         @param aFeature A reference to a client owned TFeatureEntry object.
+                         Must contain UID, status flags and data of the feature.
+         @return Error Code. KErrNone if the feature was succesfully added.
+                             KErrPermissionDenied if capability check fails.
+                             KErrAlreadyExists if the feature already exists 
+                             in the device. 
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded, or when "out of memory"
+                             occured in a previous call to this function during 
+                             the caching process. 
+                             KErrNoMemory if out-of-memory occured during caching.
+                             Otherwise one of the Symbian error codes.
+
+         @see TFeatureEntry
+	     @see TFeatureFlags
+        */
+        IMPORT_C TInt AddFeature( TFeatureEntry& aFeature );
+
+        /**
+         Deletes a feature.
+         Note: WriteDeviceData capability required.
+
+         @param aFeature Feature UID.
+         @return Error Code. KErrNone if the feature was successfully deleted.
+                             KErrAccessDenied if the feature is not runtime.
+                             KErrPermissionDenied if capability check fails.
+                             KErrNotFound if the feature does not exist. 
+                             KErrArgument if the maximum number of cached features 
+                             during a Software Installer (SWI) install/uninstall
+                             session has been exceeded.
+                             KErrNoMemory if out-of-memory occured during caching.
+                             Otherwise one of the Symbian error codes. 
+
+         @see TFeatureEntry
+	     @see TFeatureFlags
+        */
+        IMPORT_C TInt DeleteFeature( TUid aFeature );
+
+        /**
+         Lists all supported features.
+
+         @param aSupportedFeatures A reference to a client owned RFeatureUidArray array which
+                                   will be filled with the UIDs of supported features.
+         @return Error code. KErrNone if client owned array was successfully
+                             filled with IDs of supported features.
+                             KErrServerBusy if there was ongoing enabling or
+                             disabling of some feature(s) and Feature Manager Server
+                             could not return unambiguous list of supported features.
+                             KErrNoMemory if out-of-memory occured during caching. 
+                             Otherwise one of the Symbian error codes.
+        */
+        IMPORT_C TInt ListSupportedFeatures( RFeatureUidArray& aSupportedFeatures );
+
+        /**
+         Calling this method informs Feature Manager that a software installer (SWI) 
+         launched executable is going to set, add, delete, enable or disable features 
+         in Feature Manager. This mandates Feature Manager to cache all modification 
+         calls issued by that executable until a call to SWIEnd is made to commit them 
+         to Feature Manager. This prevents against situations where the installation is
+         user-aborted without being able to roll back direct feature manipulations. 
+
+         @return Error code. KErrNone if Feature Manager has accepted the request to use 
+        					 the caching APIs. 
+							 KErrInUse if the caching APIs are already in use by another 
+							 exe launched by the SWI. 
+							 KErrNotReady if there is no software installation in progress. 
+        */
+        IMPORT_C TInt SWIStart();
+
+        /**
+         Mandates Feature Manager to stop caching and prepare to commit the cached
+         feature manipulations performed by the executable launched by SWI during
+         installation into Feature Manager. The cached features are committed only
+         after that installation of the executable is successfully completed. 
+         This API must be called before a timeout managed by Feature Manager times 
+         out. Otherwise the cached features will be dumped.
+
+         @return Error code. KErrNone when SWIEnd call is received by a client or when an abort occurs 
+         					 prior to the timeout managed by Feature Manager expires. 
+							 KErrNotReady if SWIStart was not called before calling this 
+							 function, or because the timeout managed by Feature Manager 
+							 had timed out. 
+							 KErrGeneral an indication that an out-of-memory condition
+							 was encountered during caching which will force FeatMgr to 
+							 disregard the whole cache.
+							 KErrNoMemory if an out-of-memory condition was encountered 
+							 whilst reserving memory in the features list for the new 
+							 features t be added, or if an out-of-memory occured in a call
+							 to AddFeaure() during caching..
+							 Otherwise one of the Symbian error codes.							 
+        */
+        IMPORT_C TInt SWIEnd();
+        
+	private:         
+	    
+	    /**
+	     Used for resource counting.
+	    */
+	    TBool iInitialized;
+
+	    /**
+	     Reserved for future use. Initialised to 0 on construction.
+	    */
+        TUint32 iReserved1;
+
+	     /**
+	     Reserved for future use. Initialised to 0 on construction.
+	    */
+	    TUint32 iReserved2;
+
+    };
+
+/**
+ @code
+ // replace <featureUID> with a real UID )
+
+ #include <featmgr/featurecontrol.h>
+ #include <featmgr/featureinfo.h> // for feature definitions
+
+ CMyClass::MyMethodL()
+     {
+     // Replace KFeatureUidx with real feature uid.
+     // Open() must be called before calling any other methods.
+     // Disconnect is done by calling the Close() method.
+     RFeatureControl featureControl;
+     TInt err = featureControl.Open();
+
+     if ( err == KErrNone )
+         {
+         // Query multiple features statuses (single IPC-call, so less overhead)
+
+          RFeatureArray uids;
+          CleanupClosePushL(uids);
+
+          uids.AppendL( KFeatureUid1 );
+          uids.AppendL( KFeatureUid2 );
+          TInt err = control.FeaturesSupported( uids );
+
+          if ( err == KErrNone )
+              {
+              TInt index;
+
+              index = uids.Find( KFeatureUid1 );
+              if(index == KErrNotFound)
+                  {
+                  // Feature does not exist (result is analogous if KFeatureUid1
+                  // is not appended in uids array before query).
+                  }
+              else
+                  {
+                  iFeature1Supported = uids[index].FeatureFlags().IsSet( EFeatureSupported );
+                  }
+
+              index = uids.Find( KFeatureUid2 );
+              if(index == KErrNotFound)
+                  {
+                  // Feature does not exist (result is analogous if KFeatureUid2
+                  // is not appended in uids array before query).
+                  }
+              else
+                  {
+                  TBool feature2Supported = uids[index].FeatureFlags().IsSet( EFeatureSupported );
+                  TUint32 data = uids[index].FeatureData();
+                  // Do something with support-information and data
+                  ...
+                  }
+              }
+          CleanupStack::PopAndDestroy(&uids);
+
+
+         // Query single feature status
+
+          err = control.FeatureSupported( KFeatureUid3 );
+          if( err == KFeatureSupported )
+              {
+              // do something with enabled feature
+              }
+
+
+         // Query single feature status and data
+
+          TFeatureEntry entry( KFeatureUid4 );
+          err = control.FeatureSupported( entry );
+          if( err == KFeatureSupported )
+              {
+              TUint32 data = entry.FeatureData();
+              // do something with enabled feature's data
+              }
+          else if( err == KFeatureUnsupported )
+              {
+              // do or do not something with disabled feature's data
+              }
+
+
+         // Enable some feature.
+
+         // EnableFeature() and DisableFeature() methods return
+         // KErrNone if the feature was succesfully enabled or disabled,
+         // KErrAccessDenied if the feature is not modifiable.
+         // KErrPermissionDenied a capability check fails,
+         // KErrNotFound if the feature does not exist and
+         // otherwise one of the Symbian error codes.
+         err = featureControl.EnableFeature( <featureUID> );
+
+         // do something
+
+
+         // List all supported features.
+
+         // A client owned RFeatureUidArray array which will be filled with
+         // the UIDs of supported features.
+         RFeatureUidArray supportedFeatures;
+
+         // ListSupportedFeatures() returns one of the Symbian error codes.
+         err = featureControl.ListSupportedFeatures( supportedFeatures );
+
+         // do something
+
+         // Closes the array and frees all memory allocated to the array.
+         supportedFeatures.Close();
+
+
+         // Remember to call CloseL after using RFeatureControl.
+         // It disconnects the Feature Manager server.
+         featureControl.Close();
+         }
+
+     }
+ @endcode
+*/
+
+#endif      // FEATURECONTROL_H
+
+// End of File