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
|
page 80,132
title CP/DOS DosFindClose mapper
include find.inc
FindSegment segment word public 'find'
; We will use the offset into the segment 'FindSegment' as the handle that we
; return and use in subsequent FindNext and FindClose calls. The data that is
; in the word is the offset into the 'FindSegment' to the DTA that we should
; use.
extrn FindDTAs:word
extrn FindHandles:word
FindSegment ends
; ************************************************************************* *
; *
; * MODULE: DosFindClose
; *
; * FUNCTION: Close Find Handle
; *
; * FUNCTION: This module closes the directory handle used by CP/DOS
; * in a find first/find next search. Since PC/DOS does not
; * use directory handles it will simply return to the caller
; * removing the parameters passed on the stack.
; *
; * CALLING SEQUENCE:
; *
; * PUSH WORD DirHandle ; Directory search handle
; * CALL DosFindClose
; *
; *
; * RETURN SEQUENCE:
; *
; * IF ERROR (AX not = 0)
; *
; * AX = Error Code:
; *
; *
; * MODULES CALLED: None
; *
; *************************************************************************
public DosFindClose
.sall
.xlist
include macros.inc
.list
str struc
old_bp dw ?
return dd ?
DirHandle dw ? ; dirctory search handle
str ends
dosxxx segment byte public 'dos'
assume cs:dosxxx,ds:nothing,es:nothing,ss:nothing
DosFindClose proc far
Enter DosFindClose ; push registers
mov ax,seg FindSegment ; get address to our data
mov ds,ax
assume ds:FindSegment
; Close the handle
; The 'DirHandle' that the mapper returns from FindFirst, is the offset into
; 'FindSegment' of the pointer to the DTA for that Handle. The 08000h bit
; of the pointer is used to indicate that the handle is open. Reset the bit.
; Special Logic to handle DirHandle = 1
mov si,[bp].DirHandle ; get directory hanlde
cmp si,1 ; handle = 1??
jne CheckForClose ; branch if not
mov si,offset FindSegment:FindHandles
CheckForClose:
test ds:[si],OpenedHandle ; handle is open ??
jnz OkToClose ; go and close if it is open
mov ax,6 ; else load error code
jmp ErrorExit ; return
OkToClose:
and ds:[si],not OpenedHandle ; set close flag
xor ax,ax ; set good return code
ErrorExit:
mexit ; pop registers
ret size str - 6 ; return
DosFindClose endp
dosxxx ends
end
|
