; ; File: ; execrh.asm ; Description: ; request handler for calling device drivers ; ; Copyright (c) 1995, 1998 ; 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. ; ; $Logfile: C:/usr/patv/dos-c/src/kernel/execrh.asv $ ; ; $Id$ ; ; $Log$ ; Revision 1.3 2000/05/25 20:56:21 jimtabor ; Fixed project history ; ; Revision 1.2 2000/05/08 04:30:00 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 1.3 2000/03/09 06:07:11 kernel ; 2017f updates by James Tabor ; ; Revision 1.2 1999/08/10 17:57:12 jprice ; ror4 2011-02 patch ; ; Revision 1.1.1.1 1999/03/29 15:40:54 jprice ; New version without IPL.SYS ; ; Revision 1.4 1999/02/08 05:55:57 jprice ; Added Pat's 1937 kernel patches ; ; Revision 1.3 1999/02/01 01:48:41 jprice ; Clean up; Now you can use hex numbers in config.sys. added config.sys screen function to change screen mode (28 or 43/50 lines) ; ; Revision 1.2 1999/01/22 04:13:25 jprice ; Formating ; ; Revision 1.1.1.1 1999/01/20 05:51:01 jprice ; Imported sources ; ; ; Rev 1.3 06 Dec 1998 8:45:06 patv ;Bug fixes. ; ; Rev 1.2 29 May 1996 21:03:30 patv ;bug fixes for v0.91a ; ; Rev 1.1 01 Sep 1995 17:54:22 patv ;First GPL release. ; ; Rev 1.0 02 Jul 1995 9:05:34 patv ;Initial revision. ; $EndLog$ ; %include "segs.inc" segment _TEXT ; _execrh ; Execute Device Request ; ; execrh(rhp, dhp) ; request far *rhp; ; struct dhdr far *dhp; ; ; ; The stack is very critical in here. ; global _execrh _execrh: push bp ; perform c entry mov bp,sp push bp ; it will get destroyed push bx ; random char on display push si push es ; sometimes it get lost push ds lds si,[bp+8] ; ds:si = device header les bx,[bp+4] ; es:bx = request header push cs ; do this, the right way! push word exit_execrh ; like 68k code push ds push word [ds:si+8] ; interrupt push ds push word [ds:si+6] ; strategy retf exit_execrh: sti ; damm driver turn off ints cld ; has gone backwards pop ds pop es pop si pop bx pop bp mov sp,bp pop bp ret global _init_call_execrh _init_call_execrh: push bp mov bp,sp push word [bp+12] push word [bp+10] push word [bp+8] push word [bp+6] call _execrh mov sp,bp pop bp retf