// Copyright (c) 2006-2010 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 __SQLSECURITYIMPL_H__

#define __SQLSECURITYIMPL_H__

#include <sqldb.h>

#include "SqlBufFlat.h"		//RSqlBufFlat

//Forward declarations

class TSqlSecurityPolicyIterator;

/**

CSqlSecurityPolicy class implements RSqlSecurityPolicy.

Current CSqlSecurityPolicy implementation uses a flat buffer (see RSqlBufFlat class) as a storage for the database 

objects security policies.

By default the flat buffer has threee entries:

 - entry 0 is a system entry and keeps the count of the database security entries;

 - entry 1 is reserved for the default database security policy. This is a nameless entry;

 - entry 2 is reserved for the database security policies: read, write and schema. This is a nameless entry;

The flat buffer may have more entries if database object security policies are added. In this case each flat buffer entry

has a 16-bit encoded database object name, kept at the end of the entry, after the database object security policy data and

database object name length.

Note: Current CSqlSecurityPolicy implementation can have no more than 13 database object security policy entries.

An access to the flat buffer can be obtained via CSqlSecurityPolicy::BufFlat() methods (const and non-const).

There are two ways to externalize (resp. internalize) CSqlSecurityPolicy data:

 - (1) using CSqlSecurityPolicy::ExternalizeL()/CSqlSecurityPolicy::InternalizeL();

 - (2) using CSqlSecurityPolicy::BufFlat() to get an access to the flat buffer and then externalize/internalize the buffer.

       CSqlSecurityPolicy class has only one data member which is the flat buffer;

TSqlSecurityPolicyIterator class gives a convinient way to access the security policies kept inside the flat buffer.

The given access is a read-only.

@see RSqlSecurityPolicy

@see RSqlBufFlat

@see TSqlSecurityPolicyIterator

@see RSqlSecurityPolicy::TPolicyType

@see RSqlSecurityPolicy::TObjectType

@see CSqlSecurityPolicy::NewL()

@see CSqlSecurityPolicy::NewLC()

@see CSqlSecurityPolicy::SetDefaultPolicy()

@see CSqlSecurityPolicy::SetDbPolicy()

@see CSqlSecurityPolicy::SetPolicy()

@see CSqlSecurityPolicy::DefaultPolicy()

@see CSqlSecurityPolicy::DbPolicy()

@see CSqlSecurityPolicy::Policy()

@see CSqlSecurityPolicy::ExternalizeL()

@see CSqlSecurityPolicy::InternalizeL()

@see CSqlSecurityPolicy::BufFlat()

@internalComponent

*/

NONSHARABLE_CLASS(CSqlSecurityPolicy) : public CBase

	{

	friend class TSqlSecurityPolicyIterator;

	struct TPolicyItem;

public:

	static CSqlSecurityPolicy* NewL(const TSecurityPolicy& aDefaultPolicy);

	static CSqlSecurityPolicy* NewLC(const TSecurityPolicy& aDefaultPolicy);

	virtual ~CSqlSecurityPolicy();

	void SetDefaultPolicy(const TSecurityPolicy& aPolicy);

	void SetDbPolicy(RSqlSecurityPolicy::TPolicyType aPolicyType, const TSecurityPolicy& aPolicy);

	TInt SetPolicy(RSqlSecurityPolicy::TObjectType aObjectType, const TDesC& aObjectName, RSqlSecurityPolicy::TPolicyType aPolicyType, const TSecurityPolicy& aPolicy);

	TSecurityPolicy DefaultPolicy() const;

	TSecurityPolicy DbPolicy(RSqlSecurityPolicy::TPolicyType aPolicyType) const;

	TSecurityPolicy Policy(RSqlSecurityPolicy::TObjectType aObjectType, const TDesC& aObjectName, RSqlSecurityPolicy::TPolicyType aPolicyType);

	TInt Count() const;

	const RSqlBufFlat&	BufFlat() const;

	RSqlBufFlat& BufFlat();

private:

	CSqlSecurityPolicy();

	void ConstructL(const TSecurityPolicy& aDefaultPolicy);

	inline static TInt PolicyType2Index(RSqlSecurityPolicy::TPolicyType aPolicyType);

	inline static TPolicyItem* PolicyItemPtr(const RSqlBufFlat::TCell* aBegin, const RSqlBufFlat::TCell* aCurrent);

	const TPolicyItem* FindPolicyItemPtr(RSqlSecurityPolicy::TObjectType aObjectType, const TDesC& aObjectName) const;

	void SetCount(TInt aCount);

private:

	enum {

		 EPolicyTypeCount	= 3,					//Schema, Read, Write policy types

		 EMaxCount 			= 16,					//iBufFlat max element count. The database cannot have more than EMaxCount security policies.

		 ECountIdx			= 0,					//The index of the policy counter

		 EDefaultPolicyIdx	= 1,					//The index of the default policy type in iBufFlat

		 EDbPolicyIdx		= 2						//The index of the database policy type in iBufFlat

		 };					

	//The database security policies are kept in objects of TPolicyItem type.

	//If particular TPolicyItem object represents the database security policies, then the memory layout is:

	//    [SchemaPolicy]

	//    [ReadPolicy]

	//    [WritePolicy]

	//If particular TPolicyItem object represents table security policies, then the memory layout is:

	//    [SchemaPolicy]

	//    [ReadPolicy]

	//    [WritePolicy]

	//    [The length of the table name - 32-bit integer]

	//    [The table name]

	//As you can see, TPolicyItem does not have "name length" and "name" data members. If that is needed, an appropriate block of memory will be allocated for the TPolicyItem object.

	//There SQL platform security interface currently supports only database security policies, but the implementation is capable of handling also table security policies.

	struct TPolicyItem

		{

		enum {EPolicyTypeCount	= 3};				//Schema, Read, Write policy types. The same as the declaration above.

		TSecurityPolicy iPolicy[EPolicyTypeCount];	//Database object policies

		//Database object name size will be after the end of TPolicyItem object

		inline TInt* NameSizePtr() 

			{

			//See the comments of the TPolicyItem structure above.

			//coverity[overrun-local]

			return reinterpret_cast <TInt*> (reinterpret_cast <TUint8*> (iPolicy) + sizeof(iPolicy));

			}

		inline TInt NameSize() const 

			{

			//See the comments of the TPolicyItem structure above.

			//coverity[overrun-local]

			return *reinterpret_cast <const TInt*> (reinterpret_cast <const TUint8*> (iPolicy) + sizeof(iPolicy));

			}

		//Database object name will be after the end of TPolicyItem object + sizeof(TInt)

		inline const TUint16* NamePtr() const 

			{

			//See the comments of the TPolicyItem structure above.

			//coverity[overrun-local]

			return reinterpret_cast <const TUint16*> 

				(reinterpret_cast <const TUint8*> (iPolicy) + sizeof(iPolicy) + sizeof(TInt));

			}

		inline TUint16* NamePtr() 

			{

			//See the comments of the TPolicyItem structure above.

			//coverity[overrun-local]

			return reinterpret_cast <TUint16*> (reinterpret_cast <TUint8*> (iPolicy) + sizeof(iPolicy) + sizeof(TInt));

			}

		inline static TInt CalcSize(TInt aNameLen) 

			{

			return sizeof(TPolicyItem) + sizeof(TInt) + aNameLen * sizeof(TUint16);

			}

		};	

	RSqlBufFlat			iBufFlat;

	};

/**

CSqlSecurityPolicy container read-only iterator.

Usage:

@code

//Valid CSqlSecurityPolicy instance.

CSqlSecurityPolicy* securityPolicy;

...

TSqlSecurityPolicyIterator it(*securityPolicy);

//The following variables will be initialized on each iteration

RSqlSecurityPolicy::TObjectType objectType;

TPtrC objectName;

RSqlSecurityPolicy::TPolicyType policyType;

TSecurityPolicy policy;

while(it.Next(objectType, objectName, policyType, policy))

	{

	//"objectType" is initialized with the object type (see RSqlSecurityPolicy::TObjectType)

	//"objectName" is initialized with the object name (database table name)

	//"policyType" is initialized with the policy type (see RSqlSecurityPolicy::TPolicyType)

	//"policy" is initialized with the security policy data (see TSecurityPolicy)

	<do something with the policy>;

	}

@endcode

@see CSqlSecurityPolicy

@see RSqlSecurityPolicy::TObjectType

@see RSqlSecurityPolicy::TPolicyType

@see TSecurityPolicy

@internalComponent

*/

NONSHARABLE_CLASS(TSqlSecurityPolicyIterator)

	{

public:

	TSqlSecurityPolicyIterator(const CSqlSecurityPolicy& aSqlSecurityPolicy);

	TBool Next(RSqlSecurityPolicy::TObjectType& aObjectType, TPtrC& aObjectName, RSqlSecurityPolicy::TPolicyType& aPolicyType, TSecurityPolicy& aPolicy);

private:

	const RSqlBufFlat::TCell* 	iBegin;

	const RSqlBufFlat::TCell* 	iCurrent;

	const RSqlBufFlat::TCell* 	iEnd;

	TInt 						iCurPolicyIdx;

	};

#endif//__SQLSECURITYIMPL_H__