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;0
page 80,132
title CP/DOS DosError mapper
;**********************************************************************
;*
;* MODULE: doserror
;*
;* ;AN000; PCDOS 4.00 ptm p2629 - Drive not ready yields FORMAT TERMINATED
;*
;*********************************************************************
SystemIsHandling equ 1 ; system handles errors
AppIsHandling equ 0 ; application handle errors
;------------------------------------------------------------;;;
databuff segment public 'databuff' ;;;
;;;
errorstate db SystemIsHandling ;;;
;;;
databuff ends ;;;
;------------------------------------------------------------;;;
dosxxx segment byte public 'dos'
assume cs:dosxxx,ds:nothing,es:nothing,ss:nothing
public doserror
.sall
.xlist
include macros.inc
.list
str struc
old_bp dw ?
Return dd ?
Flag dw ? ; error flag; 0 = APP handle error
str ends ; 1 = System handle error
DosError proc far
Enter doserror ; Push registers
mov ax,seg databuff ;-->RW
mov ds,ax ;-->RW
assume ds:databuff ;-->RW
mov ax,[bp].flag ; get error flag
cmp ax,AppIsHandling ; check who should handle errors
je apperrorhandle ; branch if application handles error
cmp ax,SystemIsHandling ; system handle error ??
je syserrorhandle ; branch if true
mov ax,1 ; else, set error code
jmp exit ; return
SysErrorHandle:
cmp errorstate,SystemIsHandling ; system handles error ??
jne setsys ; branch if not
xor ax,ax ; else set good return code
jmp exit ; return
setsys: mov errorstate,SystemIsHandling ; set flag for system
lds dx,cs:prevadrs
mov ax,02524H
int 21h ; set new vector
xor ax,ax ; set good return code
jmp exit ; return
AppErrorHandle:
cmp errorstate,AppIsHandling ; application handle errors
jne setapp ; branch if true
xor ax,ax ; else, set good error code
jmp exit ; return
setapp: mov errorstate,AppIsHandling ; indicate app handles error
mov ax,03524h ; Get Interrupt 24 Vector
int 21h
mov word ptr cs:prevadrs+0,bx ; save it in prevadrs
mov word ptr cs:prevadrs+2,es
mov dx,cs
mov ds,dx
mov dx,offset ApiErrorHandler ; put error interrupt handler
; as new vector
mov ax,02524H
int 21h ;set new vector
xor ax,ax ; set good error return
exit: mexit ; pop all registers
ret size str - 6 ; return
DosError endp
page
;-------------------------------------------------------
; **** Error Handler ******
; This routine will get control on a hard error, returning an error.
; If error is Drive not ready, keep retrying until drive IS ready or ^C
;-------------------------------------------------------
DriveNotReady equ 2 ;AN000;
Ignore equ 0 ;AN000;
Retry equ 1 ;AN000;
Terminate equ 2 ;AN000;
Fail equ 3 ;AN000;
prevadrs dd ? ;AN000; ;save old interrupt handler address ;;;
ApiErrorHandler proc near ;AN000;
pushf ;AN000;
cmp di,DriveNotReady ;AN000; Is it Drive Not Ready?
jne popf_and_fail_it ;AN000; If not, fail call and return
Drive_Not_Ready: ;AN000; The drive is not ready!
call dword ptr cs:prevadrs ;AN000; Get user to respond
cmp al,Terminate ;AN000; For any resonse other than terminate,
jne retry_it ;AN000; retry the operation
int 023h ;AN000; Otherwise terminate via INT 023h
popf_and_fail_it: ;AN000; Fail the operation
pop ax ;AN000; Remove garbage from stack
mov al,Fail ;AN000; Func code for fail
jmp rett ;AN000;
retry_it: ;AN000; Retry the operation
mov al,Retry ;AN000; Func code for retry
rett: ;AN000;
iret ;AN000; return
Apierrorhandler endp
;-------------------------------------------------------
;-------------------------------------------------------
dosxxx ends
end
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