IBPP, a C++ API for Firebird Server Code

///////////////////////////////////////////////////////////////////////////////
//
//	File    : $Id$
//	Subject : IBPP, Blob class implementation
//
///////////////////////////////////////////////////////////////////////////////
//
//	(C) Copyright 2000-2007 T.I.P. Group S.A. and the IBPP Team (www.ibpp.org)
//
//	The contents of this file are subject to the IBPP License (the "License");
//	you may not use this file except in compliance with the License.  You may
//	obtain a copy of the License at http://www.ibpp.org or in the 'license.txt'
//	file which must have been distributed along with this file.
//
//	This software, distributed under the License, is distributed on an "AS IS"
//	basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the
//	License for the specific language governing rights and limitations
//	under the License.
//
///////////////////////////////////////////////////////////////////////////////
//
//	COMMENTS
//	* Tabulations should be set every four characters when editing this file.
//
///////////////////////////////////////////////////////////////////////////////

#ifdef _MSC_VER
#pragma warning(disable: 4786 4996)
#ifndef _DEBUG
#pragma warning(disable: 4702)
#endif
#endif

#include "_ibpp.h"

#ifdef HAS_HDRSTOP
#pragma hdrstop
#endif

using namespace ibpp_internals;

//	(((((((( OBJECT INTERFACE IMPLEMENTATION ))))))))

void BlobImpl::Open()
{
	if (mHandle != 0)
		throw LogicExceptionImpl("Blob::Open", _("Blob already opened."));
	if (mDatabase == 0)
		throw LogicExceptionImpl("Blob::Open", _("No Database is attached."));
	if (mTransaction == 0)
		throw LogicExceptionImpl("Blob::Open", _("No Transaction is attached."));
	if (! mIdAssigned)
		throw LogicExceptionImpl("Blob::Open", _("Blob Id is not assigned."));

	IBS status(mDriver);
	(mDriver->m_open_blob2)(status.Self(), mDatabase->GetHandlePtr(),
		mTransaction->GetHandlePtr(), &mHandle, &mId, 0, 0);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Open", _("isc_open_blob2 failed."));
	mWriteMode = false;
}

void BlobImpl::Create()
{
	if (mHandle != 0)
		throw LogicExceptionImpl("Blob::Create", _("Blob already opened."));
	if (mDatabase == 0)
		throw LogicExceptionImpl("Blob::Create", _("No Database is attached."));
	if (mTransaction == 0)
		throw LogicExceptionImpl("Blob::Create", _("No Transaction is attached."));

	IBS status(mDriver);
	(mDriver->m_create_blob2)(status.Self(), mDatabase->GetHandlePtr(),
		mTransaction->GetHandlePtr(), &mHandle, &mId, 0, 0);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Create",
			_("isc_create_blob failed."));
	mIdAssigned = true;
	mWriteMode = true;
}

void BlobImpl::Close()
{
	if (mHandle == 0) return;	// Not opened anyway

	IBS status(mDriver);
	(mDriver->m_close_blob)(status.Self(), &mHandle);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Close", _("isc_close_blob failed."));
	mHandle = 0;
}

void BlobImpl::Cancel()
{
	if (mHandle == 0) return;	// Not opened anyway

	if (! mWriteMode)
		throw LogicExceptionImpl("Blob::Cancel", _("Can't cancel a Blob opened for read"));

	IBS status(mDriver);
	(mDriver->m_cancel_blob)(status.Self(), &mHandle);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Cancel", _("isc_cancel_blob failed."));
	mHandle = 0;
	mIdAssigned = false;
}

int BlobImpl::Read(void* buffer, int size)
{
	if (mHandle == 0)
		throw LogicExceptionImpl("Blob::Read", _("The Blob is not opened"));
	if (mWriteMode)
		throw LogicExceptionImpl("Blob::Read", _("Can't read from Blob opened for write"));
	if (size < 1 || size > (64*1024-1))
		throw LogicExceptionImpl("Blob::Read", _("Invalid segment size (max 64Kb-1)"));

	IBS status(mDriver);
	unsigned short bytesread;
	int result = (mDriver->m_get_segment)(status.Self(), &mHandle, &bytesread,
					(unsigned short)size, (char*)buffer);
	if (result == isc_segstr_eof) return 0;	// Fin du blob
	if (result != isc_segment && status.Errors())
		throw SQLExceptionImpl(status, "Blob::Read", _("isc_get_segment failed."));
	return (int)bytesread;
}

void BlobImpl::Write(const void* buffer, int size)
{
	if (mHandle == 0)
		throw LogicExceptionImpl("Blob::Write", _("The Blob is not opened"));
	if (! mWriteMode)
		throw LogicExceptionImpl("Blob::Write", _("Can't write to Blob opened for read"));
	if (size < 1 || size > (64*1024-1))
		throw LogicExceptionImpl("Blob::Write", _("Invalid segment size (max 64Kb-1)"));

	IBS status(mDriver);
	(mDriver->m_put_segment)(status.Self(), &mHandle,
		(unsigned short)size, (char*)buffer);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Write", _("isc_put_segment failed."));
}

void BlobImpl::Info(int* Size, int* Largest, int* Segments)
{
	char items[] = {isc_info_blob_total_length,
					isc_info_blob_max_segment,
					isc_info_blob_num_segments};

	if (mHandle == 0)
		throw LogicExceptionImpl("Blob::GetInfo", _("The Blob is not opened"));

	IBS status(mDriver);
	RB result(mDriver, 100);
	(mDriver->m_blob_info)(status.Self(), &mHandle, sizeof(items), items,
		(short)result.Size(), result.Self());
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::GetInfo", _("isc_blob_info failed."));

	if (Size != 0) *Size = result.GetValue(isc_info_blob_total_length);
	if (Largest != 0) *Largest = result.GetValue(isc_info_blob_max_segment);
	if (Segments != 0) *Segments = result.GetValue(isc_info_blob_num_segments);
}

void BlobImpl::Save(const std::string& data)
{
	if (mHandle != 0)
		throw LogicExceptionImpl("Blob::Save", _("Blob already opened."));
	if (mDatabase == 0)
		throw LogicExceptionImpl("Blob::Save", _("No Database is attached."));
	if (mTransaction == 0)
		throw LogicExceptionImpl("Blob::Save", _("No Transaction is attached."));

	IBS status(mDriver);
	(mDriver->m_create_blob2)(status.Self(), mDatabase->GetHandlePtr(),
		mTransaction->GetHandlePtr(), &mHandle, &mId, 0, 0);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Save",
			_("isc_create_blob failed."));
	mIdAssigned = true;
	mWriteMode = true;

	size_t pos = 0;
	size_t len = data.size();
	while (len != 0)
	{
		size_t blklen = (len < 32*1024-1) ? len : 32*1024-1;
		status.Reset();
		(mDriver->m_put_segment)(status.Self(), &mHandle,
			(unsigned short)blklen, const_cast<char*>(data.data()+pos));
		if (status.Errors())
			throw SQLExceptionImpl(status, "Blob::Save",
					_("isc_put_segment failed."));
		pos += blklen;
		len -= blklen;
	}
	
	status.Reset();
	(mDriver->m_close_blob)(status.Self(), &mHandle);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Save", _("isc_close_blob failed."));
	mHandle = 0;
}

void BlobImpl::Load(std::string& data)
{
	if (mHandle != 0)
		throw LogicExceptionImpl("Blob::Load", _("Blob already opened."));
	if (mDatabase == 0)
		throw LogicExceptionImpl("Blob::Load", _("No Database is attached."));
	if (mTransaction == 0)
		throw LogicExceptionImpl("Blob::Load", _("No Transaction is attached."));
	if (! mIdAssigned)
		throw LogicExceptionImpl("Blob::Load", _("Blob Id is not assigned."));

	IBS status(mDriver);
	(mDriver->m_open_blob2)(status.Self(), mDatabase->GetHandlePtr(),
		mTransaction->GetHandlePtr(), &mHandle, &mId, 0, 0);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Load", _("isc_open_blob2 failed."));
	mWriteMode = false;

	size_t blklen = 32*1024-1;
	data.resize(blklen);

	size_t size = 0;
	size_t pos = 0;
	for (;;)
	{
		status.Reset();
		unsigned short bytesread;
		int result = (mDriver->m_get_segment)(status.Self(), &mHandle,
						&bytesread, (unsigned short)blklen,
							const_cast<char*>(data.data()+pos));
		if (result == isc_segstr_eof) break;	// End of blob
		if (result != isc_segment && status.Errors())
			throw SQLExceptionImpl(status, "Blob::Load", _("isc_get_segment failed."));

		pos += bytesread;
		size += bytesread;
		data.resize(size + blklen);
	}
	data.resize(size);
	
	status.Reset();
	(mDriver->m_close_blob)(status.Self(), &mHandle);
	if (status.Errors())
		throw SQLExceptionImpl(status, "Blob::Load", _("isc_close_blob failed."));
	mHandle = 0;
}

IBPP::Database BlobImpl::DatabasePtr() const
{
	if (mDatabase == 0) throw LogicExceptionImpl("Blob::DatabasePtr",
			_("No Database is attached."));
	return mDatabase;
}

IBPP::Transaction BlobImpl::TransactionPtr() const
{
	if (mTransaction == 0) throw LogicExceptionImpl("Blob::TransactionPtr",
			_("No Transaction is attached."));
	return mTransaction;
}

IBPP::IBlob* BlobImpl::AddRef()
{
	ASSERTION(mRefCount >= 0);
	++mRefCount;
	return this;
}

void BlobImpl::Release()
{
	// Release cannot throw, except in DEBUG builds on assertion
	ASSERTION(mRefCount >= 0);
	--mRefCount;
	try
	{
		if (mRefCount <= 0)
		{
			mDriver->Detach(this);
			delete this;
		}
	}
	catch (...) { }
}

//	(((((((( OBJECT INTERNAL METHODS ))))))))

void BlobImpl::Init()
{
	mIdAssigned = false;
	mWriteMode = false;
	mHandle = 0;
	mDatabase = 0;
	mTransaction = 0;
}

void BlobImpl::SetId(ISC_QUAD* quad)
{
	if (mHandle != 0)
		throw LogicExceptionImpl("BlobImpl::SetId", _("Can't set Id on an opened BlobImpl."));
	if (quad == 0)
		throw LogicExceptionImpl("BlobImpl::SetId", _("Null Id reference detected."));

	memcpy(&mId, quad, sizeof(mId));
	mIdAssigned = true;
}

void BlobImpl::GetId(ISC_QUAD* quad)
{
	if (mHandle != 0)
		throw LogicExceptionImpl("BlobImpl::GetId", _("Can't get Id on an opened BlobImpl."));
	if (! mWriteMode)
		throw LogicExceptionImpl("BlobImpl::GetId", _("Can only get Id of a newly created Blob."));
	if (quad == 0)
		throw LogicExceptionImpl("BlobImpl::GetId", _("Null Id reference detected."));

	memcpy(quad, &mId, sizeof(mId));
}

void BlobImpl::AttachDatabaseImpl(DatabaseImpl* database)
{
	if (database == 0) throw LogicExceptionImpl("Blob::AttachDatabase",
			_("Can't attach a NULL Database object."));

	if (mDatabase != 0) mDatabase->DetachBlobImpl(this);
	mDatabase = database;
	mDatabase->AttachBlobImpl(this);
}

void BlobImpl::AttachTransactionImpl(TransactionImpl* transaction)
{
	if (transaction == 0) throw LogicExceptionImpl("Blob::AttachTransaction",
			_("Can't attach a NULL Transaction object."));

	if (mTransaction != 0) mTransaction->DetachBlobImpl(this);
	mTransaction = transaction;
	mTransaction->AttachBlobImpl(this);
}

void BlobImpl::DetachDatabaseImpl()
{
	if (mDatabase == 0) return;

	mDatabase->DetachBlobImpl(this);
	mDatabase = 0;
}

void BlobImpl::DetachTransactionImpl()
{
	if (mTransaction == 0) return;

	mTransaction->DetachBlobImpl(this);
	mTransaction = 0;
}

BlobImpl::BlobImpl(DriverImpl* drv, DatabaseImpl* database, TransactionImpl* transaction)
	: mRefCount(0), mDriver(drv)
{
	Init();
	AttachDatabaseImpl(database);
	if (transaction != 0) AttachTransactionImpl(transaction);
}

BlobImpl::~BlobImpl()
{
	try
	{
		if (mHandle != 0)
		{
			if (mWriteMode) BlobImpl::Cancel();
			else BlobImpl::Close();
		}
	}
	catch (...) { }
	
	try { if (mTransaction != 0) mTransaction->DetachBlobImpl(this); }
		catch (...) { }
	try { if (mDatabase != 0) mDatabase->DetachBlobImpl(this); }
		catch (...) { }
}

//
//	EOF
//