int 3h

[bomz]

I ask before how free memory from library which no more use. As I see this way to do this

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icmp db "icmp.dll",0
icmpcreate db "IcmpCreateFile",0

invoke inet_addr, ADDR address
mov ebx, eax
invoke LoadLibrary, ADDR icmp
mov ebp, eax
invoke GetProcAddress, eax, ADDR icmpcreate
call eax ; IcmpCreateFile
mov edi, eax

invoke FreeLibrary, ebp


but what is this INT 3h here?
http://www.masm32.com/board/index.php?PHPSESSID=1fba624f0f2404ac83e75becf8fb6c7b&topic=1056;prev_next=next

03h​    CPU: The lowest non-reserved interrupt, it is used exclusively for debugging, and the ​INT 03​ handler is always implemented by a debugging program

[bomz]

Code Select Expand

comdlg32 db 'comdlg32.dll',0
getopenfilename db 'GetOpenFileName',0


invoke LoadLibrary, addr comdlg32
mov ebp, eax
invoke GetProcAddress, eax, addr getopenfilename
push offset ofn
call eax
invoke FreeLibrary, ebp

Is that wright? what happen's with ebp???

[jj2007]

- Insert the opcode int 3 somewhere in your code
- install Olly
- open your executable in Olly
- press F9

The rest is learning by doing and reading the manual if you can find one.

[ToutEnMasm]

but what is this INT 3h here?

It is a break point for the debugger.
With windows,it is recommended to use

Invoke debugbreak

instead.

[bomz]

OK. Thanks

why I can't get procaddress???

jmp ec
comdlg32      db 'comdlg32.dll',0
getopenfilename      db 'GetOpenFileName',0
ec:

invoke LoadLibrary, addr comdlg32
.if eax!=0
   mov ebx, eax
   invoke GetProcAddress, eax, addr getopenfilename
   .if eax!=0
      push offset ofn
      call eax
   .else
      invoke MessageBox,0,0,0,0
   .endif

   invoke FreeLibrary, ebx
.else
   invoke MessageBox,0,0,0,0
.endif

[ToutEnMasm]

why I can't get procaddress???

GetProcAddress is in the kernel32.lib (dll),this one must be loaded before the call to the function.
You need also the kernel32.inc (masm32 package) or winbase.h (.sdk) for declarations.

[bomz]

this only part of code which I replaced
invoke GetOpenFileName, addr ofn
of cource
   include \masm32\include\kernel32.inc
   includelib \masm32\lib\kernel32.lib
stay on the very beginning

invoke GetOpenFileName, addr ofn - this use 3 mb of memory of 7 my application use, so I want free it after file choose

[bomz]

jmp ec
comdlg32      db 'comdlg32.dll',0
getopenfilename      db 'GetOpenFileNameA',0   
ec:

invoke LoadLibrary, addr comdlg32
.if eax!=0
   mov ebx, eax
   invoke GetProcAddress, ebx, addr getopenfilename
   .if eax!=0
      push offset ofn
      call eax
   .else
      invoke MessageBox,0,0,0,0
   .endif

   invoke FreeLibrary, ebx
.else
   invoke MessageBox,0,0,0,0
.endif

[ToutEnMasm]

To avoid this mistakes,the use of declarations files is prefered.

include comdlg32.inc
includeliib comdlg32.lib

...and you can used GetOpenFileName without problems.

[bomz]

I use it without priblems. I want free memory.


In this way memory not be free

[ToutEnMasm]

To free memory (if it is a real problem ?),you can

put the  OPENFILENAME  structure in stack and free it when the called proc is ended.
truc proc
        LOCAL  machin:OPENFILENAME
         ;don't forget to initilialise the structure with zero
.....

unload the dll , but this is not granted to free memory.Another program can have loded it and in this case,only the count of the dll is decreased by one.

[bomz]

[dedndave]

this won't fly   :P

Code Select Expand

     invoke MessageBox,0,0,0,0

[dedndave]

here is some code that i use to get a Save filename
it is very similar to Open

Code Select Expand

FileTypeStrs     db 'Text Files',0,'*.txt',0,'All Files',0,'*.*',0,0

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;OPENFILENAME STRUCT
; lStructSize       dd ?
; hwndOwner         dd ?
; hInstance         dd ?
; lpstrFilter       dd ?
; lpstrCustomFilter dd ?
; nMaxCustFilter    dd ?
; nFilterIndex      dd ?
; lpstrFile         dd ?
; nMaxFile          dd ?
; lpstrFileTitle    dd ?
; nMaxFileTitle     dd ?
; lpstrInitialDir   dd ?
; lpstrTitle        dd ?
; Flags             dd ?
; nFileOffset       dw ?
; nFileExtension    dw ?
; lpstrDefExt       dd ?
; lCustData         dd ?
; lpfnHook          dd ?
; lpTemplateName    dd ?

        call    FnAlloc
;EAX = allocated address
;ECX = 0
;EDX = size of allocated block

        push    eax                                                      ;HFree:hBlck
        push    edx
        push    eax
        push    ecx                                                      ;lpTemplateName
        dec     edx
        push    ecx                                                      ;lpfnHook
        push    ecx                                                      ;lCustData
        push    offset FileTypeStrs+13                                   ;lpstrDefExt
        push    ecx                                                      ;nFileOffset/nFileExtension
        push    OFN_LONGNAMES or OFN_HIDEREADONLY or OFN_OVERWRITEPROMPT ;Flags or OFN_ENABLEHOOK or OFN_EXPLORER
        push    offset szSaveAs                                          ;lpstrTitle
        push    ecx                                                      ;lpstrInitialDir
        push    ecx                                                      ;nMaxFileTitle
        push    ecx                                                      ;lpstrFileTitle
        push    edx                                                      ;nMaxFile
        push    eax                                                      ;lpstrFile
        push    1                                                        ;nFilterIndex
        push    ecx                                                      ;nMaxCustFilter
        push    ecx                                                      ;lpstrCustomFilter
        push    offset FileTypeStrs                                      ;lpstrFilter
        push    hInstance                                                ;hInstance
        push    ecx                                                      ;hwndOwner
        push    76                                                       ;lStructSize
        INVOKE  GetSaveFileName,esp
        add     esp,76                                                   ;sizeof OPENFILENAME
        xor     eax,eax
        pop     edx
        pop     ecx
        cmp     al,[edx]
        jz      no_filename

;file save code here

no_filename:
        CALL    HFree

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;************************************************************

FnAlloc PROC

        mov     edx,4096
        push    edx
        INVOKE  HeapAlloc,hHeap,HEAP_ZERO_MEMORY,edx
        xor     ecx,ecx
        pop     edx
        ret

FnAlloc ENDP

;************************************************************

        OPTION  PROLOGUE:None
        OPTION  EPILOGUE:None

HFree   PROC    hBlck:DWORD

        INVOKE  HeapFree,hHeap,NULL,[esp+4]
        ret     4

HFree   ENDP

        OPTION  PROLOGUE:PrologueDef
        OPTION  EPILOGUE:EpilogueDef

;************************************************************

[bomz]

How free memory from libraries no more use

include \MASM32\INCLUDE\psapi.inc
includelib \MASM32\LIB\psapi.lib
   invoke   GetCurrentProcess
   invoke   EmptyWorkingSet, eax

http://msdn.microsoft.com/en-us/library/windows/desktop/ms682606%28v=vs.85%29.aspx

This more universal
SetProcessWorkingSetSize Minimum supported client - Windows 2000 Professional
http://msdn.microsoft.com/en-us/library/windows/desktop/ms686234%28v=vs.85%29.aspx

invoke   GetCurrentProcess
   invoke   SetProcessWorkingSetSize, eax, -1, -1