ec8b97be38
git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@535 6ac86273-5f31-0410-b378-82cca8765d1b
88 lines
2.5 KiB
NASM
88 lines
2.5 KiB
NASM
;
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; File:
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; execrh.asm
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; Description:
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; request handler for calling device drivers
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;
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; Copyright (c) 1995, 1998
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; Pasquale J. Villani
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; All Rights Reserved
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;
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; This file is part of DOS-C.
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;
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; DOS-C is free software; you can redistribute it and/or
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; modify it under the terms of the GNU General Public License
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; as published by the Free Software Foundation; either version
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; 2, or (at your option) any later version.
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;
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; DOS-C is distributed in the hope that it will be useful, but
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; WITHOUT ANY WARRANTY; without even the implied warranty of
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; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
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; the GNU General Public License for more details.
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;
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; You should have received a copy of the GNU General Public
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; License along with DOS-C; see the file COPYING. If not,
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; write to the Free Software Foundation, 675 Mass Ave,
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; Cambridge, MA 02139, USA.
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;
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; $Id$
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;
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%include "segs.inc"
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segment _TEXT
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; _execrh
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; Execute Device Request
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;
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; execrh(rhp, dhp)
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; request far *rhp;
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; struct dhdr far *dhp;
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;
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;
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; The stack is very critical in here.
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;
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global _execrh
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global _init_execrh
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%macro EXECRH 0
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push bp ; perform c entry
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mov bp,sp
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push si
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push ds ; sp=bp-8
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lds si,[bp+8] ; ds:si = device header
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les bx,[bp+4] ; es:bx = request header
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mov ax, [si+6] ; construct strategy address
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mov [bp+8], ax
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push si ; the bloody fucking RTSND.DOS
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push di ; driver destroys SI,DI (tom 14.2.03)
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call far[bp+8] ; call far the strategy
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pop di
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pop si
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mov ax,[si+8] ; construct 'interrupt' address
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mov [bp+8],ax ; construct interrupt address
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call far[bp+8] ; call far the interrupt
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sti ; damm driver turn off ints
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cld ; has gone backwards
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pop ds
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pop si
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pop bp
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ret
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%endmacro
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_execrh:
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EXECRH
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segment INIT_TEXT
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_init_execrh:
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EXECRH
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