/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_basic.hxx"

#include "sbcomp.hxx"
#include "buffer.hxx"
#include <string.h>

const static sal_uInt32 UP_LIMIT=0xFFFFFF00L;

// Der SbiBuffer wird in Inkrements von mindestens 16 Bytes erweitert.
// Dies ist notwendig, da viele Klassen von einer Pufferlaenge
// von x*16 Bytes ausgehen.

SbiBuffer::SbiBuffer( SbiParser* p, short n )
{
	pParser = p;
	n = ( (n + 15 ) / 16 ) * 16;
	if( !n ) n = 16;
	pBuf  = NULL;
	pCur  = NULL;
	nInc  = n;
	nSize =
	nOff  = 0;
}

SbiBuffer::~SbiBuffer()
{
	delete[] pBuf;
}

// Rausreichen des Puffers
// Dies fuehrt zur Loeschung des Puffers!

char* SbiBuffer::GetBuffer()
{
	char* p = pBuf;
	pBuf = NULL;
	pCur = NULL;
	return p;
}

// Test, ob der Puffer n Bytes aufnehmen kann.
// Im Zweifelsfall wird er vergroessert

sal_Bool SbiBuffer::Check( sal_uInt16 n )
{
	if( !n ) return sal_True;
	if( ( static_cast<sal_uInt32>( nOff )+ n ) >  static_cast<sal_uInt32>( nSize ) )
	{
		if( nInc == 0 )
			return sal_False;
		sal_uInt16 nn = 0;
		while( nn < n ) nn = nn + nInc;
		char* p;
		if( ( static_cast<sal_uInt32>( nSize ) + nn ) > UP_LIMIT ) p = NULL;
		else p = new char [nSize + nn];
		if( !p )
		{
			pParser->Error( SbERR_PROG_TOO_LARGE );
			nInc = 0;
			delete[] pBuf; pBuf = NULL;
			return sal_False;
		}
		else
		{
			if( nSize ) memcpy( p, pBuf, nSize );
			delete[] pBuf;
			pBuf = p;
			pCur = pBuf + nOff;
			nSize = nSize + nn;
		}
	}
	return sal_True;
}

// Angleich des Puffers auf die uebergebene Byte-Grenze

void SbiBuffer::Align( sal_Int32 n )
{
	if( nOff % n ) {
		sal_uInt32 nn =( ( nOff + n ) / n ) * n;
		if( nn <= UP_LIMIT )
		{
			nn = nn - nOff;
			if( Check( static_cast<sal_uInt16>(nn) ) )
			{
				memset( pCur, 0, nn );
				pCur += nn;
				nOff = nOff + nn;
			}
		}
	}
}

// Patch einer Location

void SbiBuffer::Patch( sal_uInt32 off, sal_uInt32 val )
{
	if( ( off + sizeof( sal_uInt32 ) ) < nOff )
	{
		sal_uInt16 val1 = static_cast<sal_uInt16>( val & 0xFFFF );
		sal_uInt16 val2 = static_cast<sal_uInt16>( val >> 16 );
		sal_uInt8* p = (sal_uInt8*) pBuf + off;
		*p++ = (char) ( val1 & 0xFF );
		*p++ = (char) ( val1 >> 8 );
		*p++ = (char) ( val2 & 0xFF );
		*p   = (char) ( val2 >> 8 );
	}
}

// Forward References auf Labels und Prozeduren
// bauen eine Kette auf. Der Anfang der Kette ist beim uebergebenen
// Parameter, das Ende der Kette ist 0.

void SbiBuffer::Chain( sal_uInt32 off )
{
	if( off && pBuf )
	{
		sal_uInt8 *ip;
		sal_uInt32 i = off;
		sal_uInt32 val1 = (nOff & 0xFFFF);
		sal_uInt32 val2 = (nOff >> 16);
		do
		{
			ip = (sal_uInt8*) pBuf + i;
			sal_uInt8* pTmp = ip;
             		i =  *pTmp++; i |= *pTmp++ << 8; i |= *pTmp++ << 16; i |= *pTmp++ << 24;

			if( i >= nOff )
			{
				pParser->Error( SbERR_INTERNAL_ERROR, "BACKCHAIN" );
				break;
			}
			*ip++ = (char) ( val1 & 0xFF );
			*ip++ = (char) ( val1 >> 8 );
			*ip++ = (char) ( val2 & 0xFF );
			*ip   = (char) ( val2 >> 8 );
		} while( i );
	}
}

sal_Bool SbiBuffer::operator +=( sal_Int8 n )
{
	if( Check( 1 ) )
	{
		*pCur++ = (char) n; nOff++; return sal_True;
	} else return sal_False;
}

sal_Bool SbiBuffer::operator +=( sal_uInt8 n )
{
	if( Check( 1 ) )
	{
		*pCur++ = (char) n; nOff++; return sal_True;
	} else return sal_False;
}

sal_Bool SbiBuffer::operator +=( sal_Int16 n )
{
	if( Check( 2 ) )
	{
		*pCur++ = (char) ( n & 0xFF );
		*pCur++ = (char) ( n >> 8 );
		nOff += 2; return sal_True;
	} else return sal_False;
}

sal_Bool SbiBuffer::operator +=( sal_uInt16 n )
{
	if( Check( 2 ) )
	{
		*pCur++ = (char) ( n & 0xFF );
		*pCur++ = (char) ( n >> 8 );
		nOff += 2; return sal_True;
	} else return sal_False;
}

sal_Bool SbiBuffer::operator +=( sal_uInt32 n )
{
	if( Check( 4 ) )
	{
		sal_uInt16 n1 = static_cast<sal_uInt16>( n & 0xFFFF );
		sal_uInt16 n2 = static_cast<sal_uInt16>( n >> 16 );
		if ( operator +=( n1 ) && operator +=( n2 ) )
			return sal_True;
		return sal_True;
	} 
	return sal_False;
}

sal_Bool SbiBuffer::operator +=( sal_Int32 n )
{
	return operator +=( (sal_uInt32) n );
}


sal_Bool SbiBuffer::operator +=( const String& n )
{
	sal_uInt16 l = n.Len() + 1;
	if( Check( l ) )
	{
		ByteString aByteStr( n, gsl_getSystemTextEncoding() );
		memcpy( pCur, aByteStr.GetBuffer(), l );
		pCur += l;
		nOff = nOff + l;
		return sal_True;
	}
	else return sal_False;
}

sal_Bool SbiBuffer::Add( const void* p, sal_uInt16 len )
{
	if( Check( len ) )
	{
		memcpy( pCur, p, len );
		pCur += len;
		nOff = nOff + len;
		return sal_True;
	} else return sal_False;
}