------------------------------------------------------------
[BUG/PRB.] VFP 9.0 FIX - RETURN TO COMMAND
January 2024
------------------------------------------------------------
CCB
1. BUG:
In vfp9 (and vfp6, vfp7, vfp8), if we use the RETURN TO command in the Destroy event code, sometimes it can not return to the specified procedure.
The bug was reported by Tomas Tamm.
2. CAUSE:
There are some BUGs in the following code.
3. RESOLUTION:
We can write some code to fix the BUG.
Fun53e674 :: ; proc near
push ecx ;0x0053e674 : 51
mov eax , dword ptr [ Data939568 ] ;0x0053e675 : a168959300
push ebx ;0x0053e67a : 53
push esi ;0x0053e67b : 56
push edi ;0x0053e67c : 57
xor edi , edi ;0x0053e67d : 33ff
test eax , eax ;0x0053e67f : 85c0
jne Label58688c ;0x0053e681 : 0f8505820400
Label53e687 ::
mov eax , dword ptr [ Data9370e8 ] ;0x0053e687 : a1e8709300
mov cl , byte ptr [ eax + 28 ] ;0x0053e68c : 8a481c
mov bl , 04h ;0x0053e68f : b304
test bl , cl ;0x0053e691 : 84cb
jne Label5868c9 ;0x0053e693 : 0f8530820400
call Fun54f6e2 ;0x0053e699 : e844100100
;
; -------------------------------------------------
; VFP 9.0 FIX - RETURN TO COMMAND
; December 2017
; -------------------------------------------------
; CCB
;
; In vfp9, sometimes the RETURN TO command can not return to the specified procedure.
;
; 2017/12/8, by ccb
;
cmp dword ptr vfpa_sys9113_data,00h
je Label53e69e
cmp dword ptr vfpa_returnto_isreturnto,01h
jne Label53e69e
mov dword ptr vfpa_returnto_isreturnto,00h
cmp eax,63h
jne Label53e69e
xor eax,eax
Label53e69e ::
mov esi , dword ptr [ Data9370e8 ] ;0x0053e69e : 8b35e8709300
mov edi , eax ;0x0053e6a4 : 8bf8
Label53e6a6 ::
mov ebx , dword ptr [ esp + 20 ] ;0x0053e6a6 : 8b5c2414
xor ecx , ecx ;0x0053e6aa : 33c9
test ebx , ebx ;0x0053e6ac : 85db
sete cl ;0x0053e6ae : 0f94c1
push esi ;0x0053e6b1 : 56
mov byte ptr [ Data93da78 ] , bl ;0x0053e6b2 : 881d78da9300
mov dword ptr [ Data93da74 ] , ecx ;0x0053e6b8 : 890d74da9300
call Fun549573 ;0x0053e6be : e8b0ae0000
test edi , edi ;0x0053e6c3 : 85ff
jne Label58690e ;0x0053e6c5 : 0f8543820400
test ebx , ebx ;0x0053e6cb : 85db
jne Label53e6e4 ;0x0053e6cd : 7515
cmp word ptr [ Data937100 ] , bx ;0x0053e6cf : 66391d00719300
jne Label53e6e4 ;0x0053e6d6 : 750c
mov edx , dword ptr [ esi + 20 ] ;0x0053e6d8 : 8b5614
cmp edx , dword ptr [ esi + 76 ] ;0x0053e6db : 3b564c
je Label53f564 ;0x0053e6de : 0f84800e0000
Label53e6e4 ::
mov eax , dword ptr [ Data937220 ] ;0x0053e6e4 : a120729300
test eax , eax ;0x0053e6e9 : 85c0
je Label53e6f9 ;0x0053e6eb : 740c
lea edi , dword ptr [ esi + 56 ] ;0x0053e6ed : 8d7e38
Label53e6f0 ::
cmp dword ptr [ eax + 72 ] , edi ;0x0053e6f0 : 397848
jnb Label586915 ;0x0053e6f3 : 0f831c820400
Label53e6f9 ::
mov ecx , dword ptr [ esi + 76 ] ;0x0053e6f9 : 8b4e4c
pushd 01h ;0x0053e6fc : 6a01
call Fun543c69 ;0x0053e6fe : e866550000
Label53e703 ::
test eax , eax ;0x0053e703 : 85c0
jne Label53e6f0 ;0x0053e705 : 75e9
jmp Label53e6f9 ;0x0053e707 : ebf0
Label53f564 ::
mov eax , dword ptr [ Data9393ac ] ;0x0053f564 : a1ac939300
mov al , byte ptr [eax] ;0x0053f569 : 8a00
cmp al , 0FBh ;0x0053f56b : 3cfb
je Label53e6e4 ;0x0053f56d : 0f8471f1ffff
cmp al , 055h ;0x0053f573 : 3c55
je Label53e6e4 ;0x0053f575 : 0f8469f1ffff
pop edi ;0x0053f57b : 5f
pop esi ;0x0053f57c : 5e
pop ebx ;0x0053f57d : 5b
pop ecx ;0x0053f57e : 59
ret 04h ;0x0053f57f : c20400
4. APPLIES TO:
VFP 6.0.8167.0
VFP 6.0.8961.0 (SP5)
VFP 7.0.0.9262
VFP 7.0.0.9465 (SP1)
VFP 8.0.0.2521
VFP 8.0.0.3117 (SP1)
VFP 9.0.0.2412
VFP 9.0.0.3504 (SP1)
VFP 9.0.0.4611 (SP2)
VFP 9.0.0.5015 (SP2)
VFP 9.0.0.5411 (SP2)
VFP 9.0.0.5721 (SP2)
VFP 9.0.0.5815 (SP2)
VFP 9.0.0.6303 (SP2)
VFP 9.0.0.6602 (SP2)
VFP 9.0.0.7423 (SP2)
The bug has been fixed in VFP Advanced.
5. REFERENCE WEBSITES:
1, baiyujia.com:
http://www.baiyujia.com
http://www.baiyujia.com/vfpdocuments/f_vfp9fix231.asp
6. OTHER:
For reference only, there is no guarantees.
Any questions or suggestions, please send me an email at ccb2000@163.com.
|