xbfilter.cpp

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/***************************************************************************
                          xbfilter.cpp  -  description
                             -------------------
    begin                : Thu Jan 17 2002
    copyright            : (C) 2002 by 
    email                : 
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
/*  $Id: xbfilter.cpp

    Xbase project source code
  
    This file conatains a header file for the xbStack object which
    is used for handling expressions.

    Copyright (C) 1997  Startech, Gary A. Kunkel   

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Contact:

      Mail:

        Technology Associates, Inc.
        XBase Project
        1455 Deming Way #11
        Sparks, NV 89434
        USA

      Email:

        [e-mail]

      See our website at:

        xdb.sourceforge.net


    V 1.0   10/10/97   - Initial release of software
    V 1.5   1/2/97     - Added memo field support
    V 1.6a  4/1/98     - Added expression support
    V 1.6b  4/8/98     - Numeric index keys
    V 1.8.x 3/29/99    - Initial support for filters added
*/

#ifdef __GNUG__
  #pragma implementation "xbfilter.h"
#endif

#ifdef __WIN32__
#include "xbconfigw32.h"
#else
#include "xbconfig.h"
#endif

#include "xbase.h"
#include "xbexcept.h"

/*! \file xbfilter.cpp
*/

#ifdef XB_FILTERS
/************************************************************************/
//! Short description.
/*!
  \param dbf
  \param index
  \param exp
*/
xbFilter::xbFilter( xbDbf * dbf, xbIndex * index, char * exp )
{
  xbShort rc;
  Status = 0;
  CurFilterRecNo = 0L;
  d = dbf;
  i = index;

  if(( rc = d->xbase->ParseExpression( exp, d )) != XB_NO_ERROR )
    Status = rc;
  else{
    e = d->xbase->GetExpressionHandle();
    if( d->xbase->GetExpressionResultType( e ) != 'L' )
      Status = XB_PARSE_ERROR;
  }
}
/***********************************************************************/
//! Short description.
/*!
*/
xbShort xbFilter::GetFirstFilterRec()
{
  xbShort rc;

  if( Status ) 
    return Status;

  if( i )
    rc = i->GetFirstKey();
  else
    rc = d->GetFirstRecord();

  while( rc == XB_NO_ERROR ){
    if(( rc = d->xbase->ProcessExpression( e )) != XB_NO_ERROR )
      xb_error( rc );

  cout << "xbfilter fixme" << endl;
//    if( d->xbase->GetInt()){
      CurFilterRecNo = d->GetCurRecNo();
      return XB_NO_ERROR;
//    }
    if( i )
      rc = i->GetNextKey();
    else
      rc = d->GetNextRecord();
  }
  return rc;
}
/***********************************************************************/
//! Short description.
/*!
*/
xbShort xbFilter::GetLastFilterRec()
{
  xbShort rc;

  if( Status ) 
    return Status;

  if( i )
    rc = i->GetLastKey();
  else
    rc = d->GetPrevRecord();

  while( rc == XB_NO_ERROR ){
    if(( rc = d->xbase->ProcessExpression( e )) != XB_NO_ERROR )
      xb_error( rc );

cout << "xbfilter fixme" << endl;
//    if( d->xbase->GetInt()){
      CurFilterRecNo = d->GetCurRecNo();
      return XB_NO_ERROR;
//    }
    if( i )
      rc = i->GetPrevKey();
    else
      rc = d->GetPrevRecord();
  }
  return rc;
}
/***********************************************************************/
//! Short description.
/*!
*/
xbShort xbFilter::GetNextFilterRec()
{
  xbShort rc;

  if( Status ) 
    return Status;

  if( !CurFilterRecNo )
    return GetFirstFilterRec();

  if( i ){
    rc = i->GetNextKey();
  }
  else
    rc = d->GetNextRecord();

  while( rc == XB_NO_ERROR ){
    if(( rc = d->xbase->ProcessExpression( e )) != XB_NO_ERROR )
      xb_error( rc );

    cout << "xbfilter fix me" << endl;
//    if( d->xbase->GetInt()){
      CurFilterRecNo = d->GetCurRecNo();
      return XB_NO_ERROR;
//    }
    if( i )
      rc = i->GetNextKey();
    else
      rc = d->GetNextRecord();
  }
  return rc;
} 
/***********************************************************************/
//! Short description.
/*!
*/
xbShort xbFilter::GetPrevFilterRec()
{
  xbShort rc;

  if( Status ) 
    return Status;

  if( !CurFilterRecNo )
    return GetLastFilterRec();

  if( i ){
    rc = i->GetPrevKey();
  }
  else
    rc = d->GetPrevRecord();

  while( rc == XB_NO_ERROR ){
    if(( rc = d->xbase->ProcessExpression( e )) != XB_NO_ERROR )
      xb_error( rc );
   cout << "xbfilter fix me" << endl;
  //  if( d->xbase->GetInt()){
      CurFilterRecNo = d->GetCurRecNo();
      return XB_NO_ERROR;
//    }
    if( i )
      rc = i->GetPrevKey();
    else
      rc = d->GetPrevRecord();
  }
  return rc;
} 
/***********************************************************************/
#endif  // XB_FILTERS_ON