/****************************************************************/
/*								*/
/*			    ioctl.c				*/
/*								*/
/*		      DOS/NT ioctl system call			*/
/*								*/
/*			Copyright (c) 1995			*/
/*			Pasquale J. Villani			*/
/*			All Rights Reserved			*/
/*								*/
/* This file is part of DOS-C.					*/
/*								*/
/* DOS-C 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, or (at your option) any later version.			*/
/*								*/
/* DOS-C 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 General Public License for more details.		*/
/*								*/
/* You should have received a copy of the GNU General Public	*/
/* License along with DOS-C; see the file COPYING.  If not,	*/
/* write to the Free Software Foundation, 675 Mass Ave,		*/
/* Cambridge, MA 02139, USA.					*/
/****************************************************************/

#include "../../hdr/portab.h"
#include "globals.h"

#ifdef PROTO
sft FAR *get_sft(COUNT);
#else
sft FAR *get_sft();
#endif

/* $Logfile:   C:/dos-c/src/kernel/ioctl.c_v  $ */
static BYTE *RcsId = "$Header:   C:/dos-c/src/kernel/ioctl.c_v   1.1   01 Sep 1995 17:54:16   patv  $";

/*
 * $Log:   C:/dos-c/src/kernel/ioctl.c_v  $
 * 
 *    Rev 1.1   01 Sep 1995 17:54:16   patv
 * First GPL release.
 * 
 *    Rev 1.0   02 Jul 1995  8:32:04   patv
 * Initial revision.
 */

COUNT 
DosDevIOctl (iregs FAR *r, COUNT FAR *err)
{
	sft FAR *s;
	COUNT hndl = r -> BX;

	/* Test that the handle is valid		*/
	if(hndl < 0)
	{
		*err = DE_INVLDHNDL;
		return 0;
	}

	/* Get the SFT block that contains the SFT	*/
	if((s = get_sft(hndl)) == (sft FAR *)-1)
	{
		*err = DE_INVLDHNDL;
		return 0;
	}

	switch(r -> AL)
	{
	case 0:
		r -> DX = s -> sft_flags;
		break;

	case 1:
		s -> sft_flags =
		  (s -> sft_dev -> dh_attr & ~SFT_MASK) | (r -> DX & SFT_MASK);
		break;

	/* default is do-nothing			*/
	}
	*err = SUCCESS;
	return 0;
}



static sft FAR *
get_sft (COUNT hndl)
{
	psp FAR *p = MK_FP(cu_psp,0);
	COUNT sys_idx;
	sfttbl FAR *sp;

	/* Get the SFT block that contains the SFT	*/
	sys_idx = p -> ps_filetab[hndl];
	for(sp = sfthead; sp != (sfttbl FAR *)-1; sp = sp -> sftt_next)
	{
		if(sys_idx < sp -> sftt_count)
			break;
		else
			sys_idx -= sp -> sftt_count;
	}

	/* If not found, return an error		*/
	if(sp == (sfttbl FAR *)-1)
		return (sft FAR *)-1;

	/* finally, point to the right entry		*/
	return (sft FAR *)&(sp -> sftt_table[sys_idx]);
}