048c87bbac
git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@305 6ac86273-5f31-0410-b378-82cca8765d1b
105 lines
4.2 KiB
C
105 lines
4.2 KiB
C
/****************************************************************/
|
||
/* */
|
||
/* break.c */
|
||
/* FreeDOS */
|
||
/* */
|
||
/* Control Break detection and handling */
|
||
/* */
|
||
/* Copyright (c) 1999 */
|
||
/* Steffen Kaiser */
|
||
/* 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 "portab.h"
|
||
#include "globals.h"
|
||
|
||
extern void ASMCFUNC spawn_int23(void);
|
||
|
||
#ifdef VERSION_STRINGS
|
||
static BYTE *RcsId = "$Id$";
|
||
#endif
|
||
|
||
/*
|
||
* $Log$
|
||
* Revision 1.7 2001/09/23 20:39:44 bartoldeman
|
||
* FAT32 support, misc fixes, INT2F/AH=12 support, drive B: handling
|
||
*
|
||
* Revision 1.6 2001/08/19 12:58:36 bartoldeman
|
||
* Time and date fixes, Ctrl-S/P, findfirst/next, FCBs, buffers, tsr unloading
|
||
*
|
||
* Revision 1.5 2001/04/15 03:21:50 bartoldeman
|
||
* See history.txt for the list of fixes.
|
||
*
|
||
* Revision 1.4 2001/03/21 02:56:25 bartoldeman
|
||
* See history.txt for changes. Bug fixes and HMA support are the main ones.
|
||
*
|
||
* Revision 1.3 2000/05/25 20:56:21 jimtabor
|
||
* Fixed project history
|
||
*
|
||
* Revision 1.2 2000/05/08 04:29:59 jimtabor
|
||
* Update CVS to 2020
|
||
*
|
||
* Revision 1.1.1.1 2000/05/06 19:34:53 jhall1
|
||
* The FreeDOS Kernel. A DOS kernel that aims to be 100% compatible with
|
||
* MS-DOS. Distributed under the GNU GPL.
|
||
*
|
||
* Revision 1.2 2000/03/09 06:07:10 kernel
|
||
* 2017f updates by James Tabor
|
||
*
|
||
* Revision 1.1 1999/04/16 21:18:17 jprice
|
||
* Steffen contributed.
|
||
*
|
||
*/
|
||
|
||
#define CB_FLG *(UBYTE FAR*)MK_FP(0x40, 0x71)
|
||
#define CB_MSK 0x80
|
||
|
||
/* Check for ^Break.
|
||
|
||
* Two sources are available:
|
||
* 1) flag at 40:71 bit 7
|
||
* 2) STDIN str<74>am via con_break()
|
||
*/
|
||
int control_break(void)
|
||
{
|
||
return (CB_FLG & CB_MSK) || con_break();
|
||
}
|
||
|
||
/*
|
||
* Handles a ^Break state
|
||
*
|
||
* Actions:
|
||
* 1) clear the ^Break flag
|
||
* 2) clear the STDIN stream
|
||
* 3) decrease the InDOS flag as the kernel drops back to user space
|
||
* 4) invoke INT-23 and never come back
|
||
*/
|
||
void handle_break(void)
|
||
{
|
||
mod_cso(CTL_C);
|
||
CB_FLG &= ~CB_MSK; /* reset the ^Break flag */
|
||
KbdFlush(); /* Er, this is con_flush() */
|
||
if (!ErrorMode) /* within int21_handler, InDOS is not incremented */
|
||
if (InDOS)
|
||
--InDOS; /* fail-safe */
|
||
|
||
spawn_int23(); /* invoke user INT-23 and never come back */
|
||
}
|