// 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:

//

#include "sqlite3.h"

#include "SqlSrvBlob.h"

#include "SqliteSymbian.h"

#include "SqlSrvUtil.h"

#include "SqlSrvStrings.h"

#include "SqlDb.h"

/**

Creates a new HBlobBuf instance.

@param aDb 			 The database handle

@param aDbName 		 The database name, zero-terminated. If the blob belongs to one of the attached databases, 

					 then the attached database name should be used as the value of aDbName, otherwise the

					 value should be "main"

@param aTableName    The name of the table to which the blob belongs, zero-terminated.

@param aColumnName   The name of the blob column, zero-terminated.

@param aRowId        The ROWID of the row to which the blob belongs

@param aMode		 Specifies the blob access mode, either HBlobBuf::EReadOnly or HBlobBuf::EReadWrite

@leave KErrNoMemory, An out of memory condition has occurred;

                     Note that the function may also leave with some other system wide errors or 

                     database specific errors categorised as ESqlDbError.

@return A pointer to the created HBlobBuf instance

@panic SqlDb 4 In _DEBUG mode. NULL aDb parameter.

@panic SqlDb 4 In _DEBUG mode. Negative or zero aRowId.

@panic SqlDb 4 In _DEBUG mode. aMode parameter is not HBlobBuf::EReadOnly or HBlobBuf::EReadWrite.

*/

HBlobBuf* HBlobBuf::NewL(sqlite3* aDb, const TDesC8& aDbName, const TDesC8& aTableName, const TDesC8& aColumnName, TInt64 aRowId, TMode aMode)

	{

	HBlobBuf* self = new (ELeave) HBlobBuf;

	CleanupStack::PushL(self);

	self->ConstructL(aDb, aDbName, aTableName, aColumnName, aRowId, aMode);

	CleanupStack::Pop(self);

	return self;

	}

/**

Initializes HBlobBuf data members with their default values.

*/

HBlobBuf::HBlobBuf() :

	iBlobHandle(NULL),

	iWrPos(KMinTInt),

	iRdPos(KMinTInt)

	{

	}

/**

Initializes a new HBlobBuf instance.

@param aDb 			 The database handle

@param aDbName 		 The database name, zero-terminated. If the blob belongs to one of the attached databases, 

					 then the attached database name should be used as a value of aDbName, otherwise the

					 value should be "main"

@param aTableName    The name of the table to which the blob belongs, zero-terminated.

@param aColumnName   The name of the blob column, zero-terminated.

@param aRowId        The ROWID of the row to which the blob belongs

@param aMode		 Specifies the blob access mode, either HBlobBuf::EReadOnly or HBlobBuf::EReadWrite

@leave KErrNoMemory, 	An out of memory condition has occurred;

                     	Note that the function may also leave with some other system wide errors or 

                    	database specific errors categorised as ESqlDbError.

@panic SqlDb 4 In _DEBUG mode. NULL aDb parameter.

@panic SqlDb 4 In _DEBUG mode. Negative or zero aRowId.

@panic SqlDb 4 In _DEBUG mode. aMode parameter is not HBlobBuf::EReadOnly or HBlobBuf::EReadWrite.

@panic SqlDb 7 In _DEBUG mode. NULL blob handle.

*/

void HBlobBuf::ConstructL(sqlite3* aDb, const TDesC8& aDbName, const TDesC8& aTableName, const TDesC8& aColumnName, TInt64 aRowId, TMode aMode)

	{

	(void)sqlite3SymbianLastOsError();//clear last OS error

	TInt err = sqlite3_blob_open(aDb, (const char*)aDbName.Ptr(), (const char*)aTableName.Ptr(), (const char*)aColumnName.Ptr(), 

								 aRowId, aMode & HBlobBuf::EReadWrite, &iBlobHandle);

	__SQLLEAVE_IF_ERROR(::Sql2OsErrCode(err, sqlite3SymbianLastOsError()));

	iBlobSize = sqlite3_blob_bytes(iBlobHandle);

	iWrPos = iRdPos = 0;

	}

/**

Closes the blob handle as part of the HBlobBuf object being destroyed.

*/

void HBlobBuf::DoRelease()

	{

/**

Closes the blob handle.

Any buffered data is delivered to the stream.

*/	

void HBlobBuf::DoSynchL()

	{

	if(iBlobHandle)

		{

		TInt err = sqlite3_blob_close(iBlobHandle);

		iBlobHandle = NULL; // the close is unconditional, even if an error occurs

		__SQLLEAVE_IF_ERROR(::Sql2OsErrCode(err, sqlite3SymbianLastOsError()));

		}	

	}

/**

Reads a data block from the blob with the specified length.

@param aPtr Pointer to the location where the blob data will be copied

@param aMaxLength The length of the data block to be read

@leave KErrNoMemory,  An out of memory condition has occurred;

       KErrEof, 	  An attempt has been made to read beyond the end of the blob;

       KErrBadHandle, NULL blob handle;

                      Note that the function may also leave with some other system 

                      wide errors or database specific errors categorised as ESqlDbError.

@return The number of bytes read.

@panic SqlDb 4 In _DEBUG mode. NULL aPtr parameter.

@panic SqlDb 4 In _DEBUG mode. Negative aMaxLength parameter.

@panic SqlDb 2 In _DEBUG mode. NULL iBlobHandle.

*/

TInt HBlobBuf::DoReadL(TAny* aPtr, TInt aMaxLength)

	{

	if(aMaxLength <= 0)

		{

		return 0;	

		}

	(void)sqlite3SymbianLastOsError();//clear last OS error

	if(iRdPos >= iBlobSize)

		{

		__SQLLEAVE(KErrEof);	

		}

	if((aMaxLength + iRdPos) > iBlobSize)

		{

		aMaxLength = iBlobSize - iRdPos;

		}

	TInt err = sqlite3_blob_read(BlobHandleL(), aPtr, aMaxLength, iRdPos);

	__SQLLEAVE_IF_ERROR(::Sql2OsErrCode(err, sqlite3SymbianLastOsError()));

	iRdPos += aMaxLength;

	return aMaxLength;

	}

/**

Writes a data block with the specified length to the blob.

@param aPtr Pointer to the location with the blob data to be written

@param aLength The length of the data block to be written

@leave KErrNoMemory,  An out of memory condition has occurred;

       KErrEof,       An attempt has been made to write beyond the end of the blob;

       KErrBadHandle, NULL blob handle;

                      Note that the function may also leave with some other system 

                      wide errors or database specific errors categorised as ESqlDbError.

@panic SqlDb 4 In _DEBUG mode. NULL aPtr parameter.

@panic SqlDb 4 In _DEBUG mode. Negative aLength parameter.

@panic SqlDb 2 In _DEBUG mode. NULL iBlobHandle.

*/

void HBlobBuf::DoWriteL(const TAny* aPtr, TInt aLength)

	{

	if(aLength <= 0)

		{

		return;

		}

	if((iWrPos + aLength) > iBlobSize)

		{

		__SQLLEAVE(KErrEof);

		}

	(void)sqlite3SymbianLastOsError();//clear last OS error

	TInt err = sqlite3_blob_write(BlobHandleL(), aPtr, aLength, iWrPos);

	err = ::Sql2OsErrCode(err, sqlite3SymbianLastOsError());

	__SQLLEAVE_IF_ERROR(err);

	iWrPos += aLength;

	}

/**

Positions the mark(s) indicated by aMark at aOffset from aLocation.

@leave KErrEof,       An attempt has been made to seek beyond the end of the blob;

	   KErrBadHandle, NULL blob handle;

                      Note that the function may also leave with some other system wide errors or 

                      database specific errors categorised as ESqlDbError.

@return The new stream position (read or write)

@panic SqlDb 2 In _DEBUG mode. NULL iBlobHandle.

@panic SqlDb 4 In _DEBUG mode. Negative aOffset parameter.

@panic SqlDb 8 In _DEBUG mode. Invalid aMark parameter.

@panic SqlDb 9 In _DEBUG mode. Invalid aLocation parameter.

*/

TStreamPos HBlobBuf::DoSeekL(MStreamBuf::TMark aMark, TStreamLocation aLocation, TInt aOffset)

	{

	TInt newPos = 0;

	switch(aLocation)

		{

	case EStreamBeginning:

		newPos = aOffset;

		break;

	case EStreamMark:

		newPos = (aMark & MStreamBuf::EWrite ? iWrPos : iRdPos) + aOffset;

		break;

	case EStreamEnd:

		newPos = iBlobSize + aOffset;

		break;

	default:

		newPos = -1;

		break;

		}

	if(newPos < 0 || newPos > iBlobSize)

		{

		__SQLLEAVE(KErrEof);

		}

	if(aMark & MStreamBuf::EWrite)

		{

		iWrPos = newPos;

		}

	else if(aMark & MStreamBuf::ERead)

		{

		iRdPos = newPos;	

		}

	return TStreamPos(newPos);

	}

/**

Returns the blob handle, if it is not NULL.

@leave KErrBadHandle, The blob handle is NULL.

@return The blob handle

*/

sqlite3_blob* HBlobBuf::BlobHandleL()

	{

	if(!iBlobHandle)

		{

		__SQLLEAVE(KErrBadHandle);

		}

	return iBlobHandle;

	}