1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
;
; process control system calls for MSDOS
;
INCLUDE DOSSEG.ASM
CODE SEGMENT BYTE PUBLIC 'CODE'
ASSUME SS:DOSGROUP,CS:DOSGROUP
.xlist
.xcref
INCLUDE DOSSYM.ASM
INCLUDE DEVSYM.ASM
.cref
.list
i_need CurrentPDB,WORD
i_need CreatePDB,BYTE
i_need NUMIO,BYTE
i_need Exit_type,BYTE
i_need INDOS,BYTE
i_need DMAADD,DWORD
i_need DidCTRLC,BYTE
SUBTTL $WAIT - return previous process error code
PAGE
;
; process control data
;
i_need exit_code,WORD ; code of exit
;
; Assembler usage:
; MOV AH, Wait
; INT int_command
; AX has the exit code
procedure $WAIT,NEAR
ASSUME DS:NOTHING,ES:NOTHING
MOV AX,[exit_code]
XOR DX,DX
MOV [exit_code],DX
transfer SYS_RET_OK
$WAIT ENDP
IF IBM
procedure $EXEC,NEAR
error error_invalid_function
$EXEC ENDP
ENDIF
IF NOT IBM
INCLUDE EXEC.ASM
ENDIF
SUBTTL Terminate and stay resident handler
PAGE
;
; Input: DX is an offset from CurrentPDB at which to
; truncate the current block.
;
; output: The current block is truncated (expanded) to be [DX+15]/16
; paragraphs long. An exit is simulated via resetting CurrentPDB
; and restoring the vectors.
;
procedure $Keep_process,NEAR
ASSUME DS:NOTHING,ES:NOTHING,SS:DOSGROUP
PUSH AX ; keep exit code around
MOV BYTE PTR [Exit_type],Exit_keep_process
MOV ES,[CurrentPDB]
CMP DX,6h ; keep enough space around for system
JAE Keep_shrink ; info
MOV DX,6h
keep_shrink:
MOV BX,DX
PUSH BX
PUSH ES
invoke $SETBLOCK ; ignore return codes.
POP DS
POP BX
JC keep_done ; failed on modification
MOV AX,DS
ADD AX,BX
MOV DS:[PDB_block_len],AX
keep_done:
POP AX
JMP SHORT exit_inner ; and let abort take care of the rest
$Keep_process ENDP
procedure Stay_resident,NEAR
ASSUME DS:NOTHING,ES:NOTHING,SS:NOTHING
MOV AX,(Keep_process SHL 8) + 0 ; Lower part is return code
ADD DX,15
MOV CL,4
SHR DX,CL
transfer COMMAND
Stay_resident ENDP
SUBTTL $EXIT - return to parent process
PAGE
;
; Assembler usage:
; MOV AL, code
; MOV AH, Exit
; INT int_command
; Error return:
; None.
;
procedure $EXIT,NEAR
ASSUME DS:NOTHING,ES:NOTHING,SS:DOSGROUP
XOR AH,AH
XCHG AH,BYTE PTR [DidCTRLC]
OR AH,AH
MOV BYTE PTR [Exit_type],exit_terminate
JZ exit_inner
MOV BYTE PTR [Exit_type],exit_ctrl_c
Exit_inner:
invoke get_user_stack
PUSH [CurrentPDB]
POP [SI.user_CS]
transfer abort_inner
$EXIT ENDP
do_ext
CODE ENDS
END
|
