/*
 *
 *  This file is part of the XForms library package.
 *
 * XForms 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, or
 * (at your option) any later version.
 *
 * XForms 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 XForms; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 *
 */


/*
 * $Id: matrix.c,v 1.5 2008/04/29 21:36:04 jtt Exp $
 *
 *.
 *  This file is part of the XForms library package.
 *  Copyright (c) 1998-2002  T.C. Zhao
 *  All rights reserved.
 *.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "include/forms.h"
#include "flimage.h"
#include "flimage_int.h"


/***************************************
 ***************************************/

void *
fl_get_matrix( int          nrows,
			   int          ncols,
			   unsigned int esize )
{
    char **mat;
    int i;

    if ( ! ( mat = fl_malloc( ( nrows + 1 ) * sizeof *mat ) ) )
		return NULL;

    mat[ 0 ] = ( void * ) FL_GET_MATRIX;

    if ( ! ( mat[ 1 ] = fl_calloc( nrows * ncols, esize ) ) )
    {
		fl_free( mat );
		return NULL;
    }

    for ( i = 2; i <= nrows; i++ )
		mat[ i ] = mat[ i - 1 ] + ncols * esize;

    return mat + 1;
}


/***************************************
 * given a piece of memory, make a matrix out of it
 ***************************************/

void *
fl_make_matrix( int            nrows,
				int            ncols,
				unsigned int   esize,
				void         * mem )
{
    char **mat = fl_malloc( ( nrows + 1 ) * sizeof *mat );
    int i;

    if ( ! mat )
		return NULL;

	mat[ 0 ] = ( char * ) FL_MAKE_MATRIX;

	for ( mat[ 1 ] = mem, i = 2; i <= nrows; i++ )
		mat[ i ] = mat[ i - 1 ] + ncols * esize;

    return mat + 1;
}


/***************************************
 ***************************************/

void
fl_free_matrix( void *p )
{
    char **matrix = p;

    if ( ! p )
		return;

    if ( matrix[ -1 ] && matrix[ 0 ] )
    {
		if ( matrix[ -1 ] == ( char * ) FL_GET_MATRIX )
			fl_free( matrix[ 0 ] );
		fl_free( matrix - 1 );
    }
}
