ioctl.c

一个用C和汇编写的Dos操作系统的源码

/****************************************************************/
/*                                                              */
/*                          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"

/* $Logfile:   C:/dos-c/src/kernel/ioctl.c_v  $ */
#ifdef VERSION_STRINGS
static BYTE *RcsId = "$Header:   C:/dos-c/src/kernel/ioctl.c_v   1.6   11 Jan 1998  2:06:22   patv  $";
#endif

/* $Log:   C:/dos-c/src/kernel/ioctl.c_v  $
 * 
 *    Rev 1.6   11 Jan 1998  2:06:22   patv
 * Added functionality to ioctl.
 * 
 *    Rev 1.5   04 Jan 1998 23:15:18   patv
 * Changed Log for strip utility
 * 
 *    Rev 1.4   16 Jan 1997 12:46:54   patv
 * pre-Release 0.92 feature additions
 * 
 *    Rev 1.3   29 May 1996 21:03:30   patv
 * bug fixes for v0.91a
 * 
 *    Rev 1.2   19 Feb 1996  3:21:34   patv
 * Added NLS, int2f and config.sys processing
 * 
 *    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.
 */
/* $EndLog$ */

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

/*
 * WARNING:  this code is non-portable (8086 specific).
 */

COUNT 
DosDevIOctl (iregs FAR *r, COUNT FAR *err)
{
	sft FAR *s;
	struct dpb FAR *dpbp;
	BYTE FAR *pBuffer = MK_FP(r -> DS, r -> DX);
	COUNT nMode;

	/* Test that the handle is valid				*/
	switch(r -> AL)
	{
	case 0x00:
	case 0x01:
	case 0x02:
	case 0x03:
	case 0x06:
	case 0x07:
	case 0x0a:
	case 0x0c:
		
		/* Get the SFT block that contains the SFT		*/
		if((s = get_sft(r -> BX)) == (sft FAR *)-1)
		{
			*err = DE_INVLDHNDL;
			return 0;
		}
		break;

	case 0x04:
	case 0x05:
	case 0x08:
	case 0x09:
	case 0x0d:
	case 0x0e:
	case 0x0f:
	case 0x10:
	case 0x11:
		if (r->BL > nblkdev)
		{    
			*err = DE_INVLDDRV;
			return 0;
		}
		else
			dpbp = &blk_devices[r -> BL];
		break;

	case 0x0b:
		/* skip, it's a special case.				*/
		break;

	default:
		*err = DE_INVLDFUNC;
		return 0;
	}


	switch(r -> AL)
	{
	case 0x00:
		/* Get the flags from the SFT				*/
		r -> DX = r -> AX = s -> sft_flags;

		/* Test for file and network SFT.  These return a 0 in	*/
		/* the AH register.					*/
		if( (s -> sft_flags & SFT_FSHARED)
		|| !(s -> sft_flags & SFT_FDEVICE))
		{
			 r -> AH = 0;
		}
		break;

	case 0x01:
		/* sft_flags is a file, return an error because you	*/
		/* can't set the status of a file.			*/
		if(!(s -> sft_flags & SFT_FDEVICE))
		{
			*err = DE_INVLDFUNC;
			return 0;
		}

		/* Set it to what we got in the DL register from the	*/
		/* user.						*/
		r -> AX = (s -> sft_flags |= (SFT_FDEVICE | r -> DL));
		break;

	case 0x0c:
		nMode = C_GENIOCTL;
		goto  IoCharCommon;
	case 0x02:
		nMode = C_IOCTLIN;
		goto  IoCharCommon;
	case 0x10:
		nMode = C_IOCTLQRY;
		goto IoCharCommon;
	case 0x03:
		nMode = C_IOCTLOUT;
	IoCharCommon:
		if(!(s -> sft_flags & SFT_FDEVICE)
		|| ((r -> AL == 0x10) && !(s -> sft_dev-> dh_attr & ATTR_QRYIOCTL))
		|| ((r -> AL == 0x0c) && !(s -> sft_dev-> dh_attr & ATTR_GENIOCTL)))
		{
			if(s -> sft_dev -> dh_attr & SFT_FIOCTL)
		 	{
				CharReqHdr.r_unit = 0;
				CharReqHdr.r_length = sizeof(request);
				CharReqHdr.r_command = nMode;
				CharReqHdr.r_count = r -> CX;
				CharReqHdr.r_trans = pBuffer;
				CharReqHdr.r_status = 0;
				execrh((request FAR *)&CharReqHdr,
				 s -> sft_dev);
				if(CharReqHdr.r_status & S_ERROR)
					return char_error(&CharReqHdr, 
					CharName(s -> sft_dev));
				if(r -> AL == 0x07)
				{
					r -> AL = 
					  CharReqHdr.r_status & S_BUSY ?
						00 : 0xff;
				}
			    	break;
			}
		}
		*err = DE_INVLDFUNC;
		return 0;

	case 0x0d:
		nMode = C_GENIOCTL;
		goto  IoBlockCommon;
	case 0x04:
		nMode = C_IOCTLIN;
		goto  IoBlockCommon;
	case 0x11:
		nMode = C_IOCTLQRY;
		goto IoBlockCommon;
	case 0x05:
		nMode = C_IOCTLOUT;
	IoBlockCommon:
		if(!(dpbp -> dpb_device -> dh_attr & ATTR_IOCTL)
		|| ((r -> AL == 0x11) && !(dpbp -> dpb_device-> dh_attr & ATTR_QRYIOCTL))
		|| ((r -> AL == 0x0d) && !(dpbp -> dpb_device-> dh_attr & ATTR_GENIOCTL)))
		{
			*err = DE_INVLDFUNC;
			return 0;
		}

		CharReqHdr.r_unit = r -> BL;
		CharReqHdr.r_length = sizeof(request);
		CharReqHdr.r_command = nMode;
		CharReqHdr.r_count = r -> CX;
		CharReqHdr.r_trans = pBuffer;
		CharReqHdr.r_status = 0;
		execrh((request FAR *)&CharReqHdr,
		 dpbp -> dpb_device);
		if(r -> AL == 0x08)
		{
			if(CharReqHdr.r_status & S_ERROR)
			{
				*err = DE_DEVICE;
				return 0;
			}
			r -> AX = (CharReqHdr.r_status & S_BUSY) ? 1 : 0;
		}
		else
		{
			if(CharReqHdr.r_status & S_ERROR)
			{
				*err = DE_DEVICE;
				return 0;
			}
		}
	    	break;

	case 0x06:
		if (s -> sft_flags & SFT_FDEVICE)
		{
		    r -> AL = s -> sft_flags & SFT_FEOF ? 0 : 0xFF;
		}
		else 
		    r -> AL = s -> sft_posit >= s -> sft_size? 0xFF : 0;
		break;

	case 0x07:
		if (s -> sft_flags & SFT_FDEVICE)
		{
			goto IoCharCommon;
		}
		r -> AL = 0;
		break;

	case 0x08:
		if (dpbp -> dpb_device -> dh_attr & ATTR_EXCALLS)
		{
			nMode = C_REMMEDIA;
			goto IoBlockCommon;
		}
		*err = DE_INVLDFUNC;
		return 0;

	case 0x09:
		r -> DX = dpbp -> dpb_device -> dh_attr;
		break;

	case 0x0a:
		r -> DX = s -> sft_dcb -> dpb_device -> dh_attr;
		break;


	case 0x0e:
		nMode = C_GETLDEV;
		goto IoLogCommon;
	case 0x0f:
		nMode = C_SETLDEV;
	IoLogCommon:
		if(!(dpbp -> dpb_device -> dh_attr & ATTR_GENIOCTL))
		{
			if(r -> BL == 0)
				r -> BL = default_drive;

			CharReqHdr.r_unit = r -> BL;
			CharReqHdr.r_length = sizeof(request);
			CharReqHdr.r_command = nMode;
			CharReqHdr.r_count = r -> CX;
			CharReqHdr.r_trans = pBuffer;
			CharReqHdr.r_status = 0;
			execrh((request FAR *)&CharReqHdr,
			 dpbp -> dpb_device);

			if(CharReqHdr.r_status & S_ERROR)
				*err = DE_ACCESS;
			else
				*err = SUCCESS;
			return 0;
		}
		*err = DE_INVLDFUNC;
		return 0;

	default:
		*err = DE_INVLDFUNC;
		return 0;
	}
	*err = SUCCESS;
	return 0;
}