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**Michael Mattias** · 19 Nov 2008, 09:40 AM

Can't be done.

The space for those variables is in your program's data segment which is TOTALLY under the control of compiler-generated code.

But how many STATIC variables can you have that it makes a difference?

But let's just say it does make a difference... if so, you can allocate that space yourself (here GlobalAlloc could be useful, or that new thing in 9x, whats that GLOBAL MEM ALLOC?), save the 4-byte handle to the block somewhere, and GlobalFree the block on WM_DESTROY.

Heck, you'd have to do this anyway if you needed your dialog procedure to be re-entrant, so go ahead and do it now.

MCM

**Gerhard Praetorius** · 19 Nov 2008, 10:46 AM

I came to these considerations when looking for memory leaks. Every time when I call a dialog containing a %LBS_NODATA listbox with an array of more than thousand items the memory occupied by the program is increasing. I checked the usual "suspects" like missing DeleteObject() but can't find a mistake. The dialog is - as most of my dialogs - situated in a DLL. Any idea?

**Michael Mattias** · 19 Nov 2008, 10:53 AM

LBS_NODATA
Specifies a no-data list box. Specify this style when the count of items in the list box will exceed one thousand. A no-data list box must also have the LBS_OWNERDRAWFIXED style, but must not have the LBS_SORT or LBS_HASSTRINGS style.

If you have a leak, I'll bet it's in your GDI code under WM_DRAWITEM. Code not shown.

**Gerhard Praetorius** · 19 Nov 2008, 11:04 AM

Code:

CASE %WM_DRAWITEM, %WM_MEASUREITEM
       IF CBWPARAM = idlist THEN
          SubclassArtilistproc GetDlgItem(CBHNDL, CBWPARAM), CBMSG, CBWPARAM, CBLPARAM
       END IF

       IF CBWPARAM = %IDC_ListSaldoLBL THEN
          SubClassArtiSaldoTBXProc GetDlgItem(CBHNDL, CBWPARAM), CBMSG, CBWPARAM, CBLPARAM
       END IF

       IF CBWPARAM = %IDC_ListSaldo2LBL THEN
          SubClassArtiSaldo2TBXProc GetDlgItem(CBHNDL, CBWPARAM), CBMSG, CBWPARAM, CBLPARAM
       END IF

Perhaps you mean the SubClassproc of the listbox?

**Gerhard Praetorius** · 19 Nov 2008, 11:31 AM

Heere is the %WM_DRAWITEM-section of ent SubClassproc:

Code:

FUNCTION SubclassArtilistproc(BYVAL hWnd AS LONG, BYVAL wMsg AS LONG, _
                              BYVAL wParam AS LONG, BYVAL lParam AS LONG) AS LONG

    LOCAL lpdis AS DRAWITEMSTRUCT PTR
    LOCAL ztxt AS ASCIIZ*%MAX_PATH
    LOCAL hPen AS DWORD,x AS DWORD
    LOCAL i AS LONG,t AS LONG,itd AS LONG
    LOCAL cnt AS LONG
    LOCAL fmt AS STRING
    LOCAL rc AS RECT
    LOCAL BkColorList,iLines,tabBMP,Topindex AS LONG
    LOCAL hBmp AS DWORD

    BkColorList = RGB(255, 255, 196)
    iLines = 2

    SELECT CASE wMsg
       CASE %WM_DRAWITEM
           lpdis = lParam
           IF @lpdis.itemID = %TIME_ZONE_ID_INVALID THEN EXIT FUNCTION

         SELECT CASE @lpdis.itemAction
         CASE %ODA_DRAWENTIRE, %ODA_SELECT
              IF @lpdis.itemID MOD 2 = 0 THEN BkColorList = RGB(192, 192, 192)

              REDIM Colors(UBOUND(gTabsArtlist) + 1) AS LONG

              'CLEAR BACKGROUND
              IF (@lpdis.itemState AND %ODS_SELECTED) = 0 THEN                 'if not selected
                 SetBkColor @lpdis.hDC, BkColorList
                 SetTextColor @lpdis.hDC, GetSysColor(%COLOR_WINDOWTEXT)
                 FillRect @lpdis.hDC, @lpdis.rcItem,CreateSolidBrush(BkColorList)
              ELSE
                 SetBkColor @lpdis.hDC, GetSysColor(%COLOR_HIGHLIGHT)             'sel text background
                 IF gWaren(@lpdis.itemID).gemerkt THEN
                    SetTextColor @lpdis.hDC,RGB(0,255,0)       'sel text color
                 ELSE
                    SetTextColor @lpdis.hDC, GetSysColor(%COLOR_HIGHLIGHTTEXT)       'sel text color
                 END IF
                 FillRect @lpdis.hDC, @lpdis.rcItem, GetSysColorBrush(%COLOR_HIGHLIGHT) 'clear background
              END IF

              IF gWaren(@lpdis.itemID).gemerkt THEN
                 FOR i = 0 TO UBOUND(Colors)
                     Colors(i) = RGB(0,128,128)
                 NEXT i
              ELSE
                 SetTextColor @lpdis.hDC, GetSysColor(%COLOR_WINDOWTEXT)       'text color
              END IF

              'draw gridlines between items
              hPen = CreatePen(%PS_SOLID, 1, GetSysColor(%COLOR_3DFACE))
              hPen = SelectObject(@lpdis.hDC, hPen)
              MoveToEx @lpdis.hDC, 0, @lpdis.rcItem.nBottom - 1, BYVAL %NULL
              LineTo @lpdis.hDC, @lpdis.rcItem.nRight, @lpdis.rcItem.nBottom - 1
              DeleteObject SelectObject(@lpdis.hDC, hPen)

              'GET ITEM'S TEXT AND DRAW TEXT
              InflateRect @lpdis.rcItem, -2, -2

              '1. line:
              ztxt = PARSE$(Get_ArtiListLines(Get_Parent(hWnd),@lpdis.itemID),$CRLF,1)

              IF INSTR(ztxt,"{bmp:Basissatz}") THEN
                 hbmp = LoadBitmap(GetModuleHandle(BYVAL %NULL),BYVAL MAKLNG(%IDB_BITMAP17,0)) 'B
              ELSEIF INSTR(ztxt,"{bmp:Gebindesatz}") THEN
                 hbmp = LoadBitmap(GetModuleHandle(BYVAL %NULL),BYVAL MAKLNG(%IDB_BITMAP19,0)) 'G
              END IF

              tabBMP = Txt_Width_Pix(Get_Parent(hWnd),EXTRACT$(ztxt,$TAB))

              IF Ist_Gebindesatz(gWaren(@lpdis.itemID)) THEN
                 Colors(4) = %GRAY
              END IF
              ListlinesClr Get_Parent(hWnd),2,ztxt,lpdis,gTabsArtlist(),Colors() 'DLLs\Dlgrout.inc

              '2. line:
              zTxt = PARSE$(Get_ArtiListLines(Get_Parent(hWnd),@lpdis.itemID),$CRLF,2)

              IF Ist_Gebindesatz(gWaren(@lpdis.itemID)) THEN
                 IF gArtilistSaldo <> %SaldoArtikelAnzahl THEN
                    Colors(4) = %GRAY
                 ELSEIF gArtilistSaldo = %SaldoArtikelAnzahl THEN
                    Colors(4) = 0
                 END IF
              END IF

              CONTROL SEND Get_Parent(hWnd), GetDlgCtrlID(hWnd), %LB_GETITEMHEIGHT, 0, 0 TO i 'Get height of one line

              IF hbmp THEN
                 rc.nLeft = 3 : rc.nRight = rc.nLeft + 12 'Set cordinates
                 rc.ntop = @lpdis.rcItem.ntop + i / iLines
                 rc.nbottom = @lpdis.rcItem.nbottom - 1
                 DrawState @lpdis.hDC, 0&, 0&, hbmp, 0&, rc.nLeft, _
                              rc.nTop + 2, 0, 0, %DST_BITMAP
                 DeleteObject hbmp
              END IF

              ListlinesClr Get_Parent(hWnd),i / 2,ztxt,lpdis,gTabsArtlist(),Colors() 'DLLs\Dlgrout.inc

              IF gWaren(@lpdis.itemID).DurchlPosten = "J" AND gArtilistSaldo <> %SaldoArtikelAnzahl THEN
                 hbmp = LoadBitmap(GetModuleHandle(BYVAL %NULL),BYVAL MAKLNG(%IDB_BITMAP18,0)) 'd red
                 rc.nLeft = tabBMP - 12 : rc.nRight = rc.nLeft + 12 'Set cordinates
                 rc.ntop = @lpdis.rcItem.ntop + i / iLines
                 rc.nbottom = @lpdis.rcItem.nbottom - 1
                 DrawState @lpdis.hDC, 0&, 0&, hbmp, 0&, rc.nLeft, _
                              rc.nTop + 2, 0, 0, %DST_BITMAP
                 DeleteObject hbmp
              END IF

              'FOCUS RECT AROUND SELECTED ITEM
              IF (@lpdis.itemState AND %ODS_SELECTED) THEN      'if selected
                 CALL DrawFocusRect(@lpdis.hDC, @lpdis.rcItem)  'draw a focus rectangle around all
              END IF

              FUNCTION = %TRUE
              EXIT FUNCTION

         CASE %ODA_FOCUS
              DrawFocusRect @lpdis.hDC, @lpdis.rcItem 'draw focus rectangle

         END SELECT
         
         ...

    END SELECT
    DIALOG GET USER hWnd, 1 TO x
    FUNCTION = CallWindowProc(x, hWnd, wMsg, wParam, lParam)
    END FUNCTION

**Michael Mattias** · 19 Nov 2008, 11:34 AM

Umm.... probably..

That is, I think you were oin the right path looking for missing DeleteObject() calls... but without seeing the code where you Get/Create the objects to be deleted, nobody can tell if you are missing a DeleteObject().

That is, somewhere you are doing a CreatePen(), CreateBrush() or CreateFont() ; but we can't tell where where that function is not 'paired' with a DeleteObject() for same.

(BTW, don't call it a "subclass proc" unless the control is actually subclassed. Not that it is an error, it's just quite confusing because the term "subclass proc" is generally used only in this case).

**Michael Mattias** · 19 Nov 2008, 11:42 AM

Well, here's one leak...

Code:

FillRect @lpdis.hDC, @lpdis.rcItem,CreateSolidBrush(BkColorList)

From that code, no way you can DeleteObject() of the brush you are creating.

MCM

**Gerhard Praetorius** · 19 Nov 2008, 11:54 AM

Code:

LOCAL hBrush as long
hBrush = CreateSolidBrush(BkColorList)
FillRect @lpdis.hDC, @lpdis.rcItem,hBrush
DeleteObject hBrush

Thank's a lot! I have to change this at many points of my code.

**Kev Peel** · 19 Nov 2008, 02:03 PM

One more thing before you go...

This code is incorrect:

Code:

SELECT CASE @lpdis.itemAction

Note in the SDK docs for DRAWITEMSTRUCT that "itemAction" can be one or more of the provided values, meaning that it's a bit mask. You must test for each value using the AND operator, like this:

Code:

IF (@lpdis.itemAction AND %ODA_FOCUS) THEN ' Draw control in focused state.

**Gerhard Praetorius** · 19 Nov 2008, 02:16 PM

Probably you are right. But almost all samples from the POFFs use it like I did, and it works.

**Michael Mattias** · 19 Nov 2008, 02:38 PM

Probably you are right. But almost all samples from the POFFs use it like I did, and it works

How do you know it "works" ALL THE TIME? (Answer: you don't).

Taking the time to "do it right" will always pay for itself in the long run.

**Michael Mattias** · 19 Nov 2008, 02:39 PM

I take it the question about de-allocating STATIC variables is now off the table?

**Gerhard Praetorius** · 19 Nov 2008, 02:55 PM

I changed all CreateSolidBrush() as shown above (DeleteObject hbrush) but my program is still eating memory... Is it shure that there is no connection with the allocated memory for STATIC variables which cannot be released?

**Chris Holbrook** · 19 Nov 2008, 04:42 PM

The most powerful debugging technique which I have used under similar circumstances is to cut out parts of the application until the problem goes away. Then I know that the last part cut out contained the problem. Then I build a miniature application with just enough functionality to demonstate the problem. If this does not lead me to the solution, then at least I have a compileable application which can be posted here for these world-class problem-solvers to get their teeth into!

**Michael Mattias** · 20 Nov 2008, 07:17 AM

... Is it shure that there is no connection with the allocated memory for STATIC variables which cannot be released?

Yes.

**Gerhard Praetorius** · 20 Nov 2008, 07:46 AM

...can be posted here for these world-class problem-solvers to get their teeth into...

Concerning this point I tell you a short story: In August 2007 I had informed the PB-support about a bug in PBFORMS. Pretty often when you assign new accelerators to an existing menu PBFORMS uses the wrong identifyers and does not join the accelerators to the related menu. So you have to correct that manually which, in the long run, takes a lot of time. I had sent a code snippet which made the problem very clear and repeatable, and Jeff Daniels from Support said he would pass this to the R&D department. I am still waiting for an answer, exactly 455 days until now(!), and the bug has neither been fixed.

But this does not belong to the current thread. Concerning the memory issue I found something interesting: The lost of memory seems to be a problem of PowerBasic rather than of my faulty code. The following snippet shows: When you call, from a console application, a windows-dialog situated in a DLL, more and more memory is lost each time you call the function in the DLL. And this without one relevant line in the called function! I have tested the memory with the "process_memoryinfo"-tool: http://www.powerbasic.com/support/pb...ad.php?t=24120

Console-app:

Code:

#INCLUDE "WIN32API.INC"
#INCLUDE "process_memoryinfo.inc"

DECLARE FUNCTION ShowTOPWindow  LIB "MEMTEST.DLL" (BYVAL hParent AS DWORD) AS LONG
DECLARE SUB Call_FunctionInDLL(BYVAL hPrnt AS LONG)
    

FUNCTION WINMAIN(BYVAL hCurInstance AS LONG, _
                 BYVAL hPrevInstance AS LONG, _
                 lpszCmdLine AS ASCIIZ PTR, _
                 BYVAL nCmdShow AS LONG) AS LONG
                 
    Call_FunctionInDLL GetDeskTopWindow()
                 
END FUNCTION

SUB Call_FunctionInDLL(BYVAL hPrnt AS LONG)
    LOCAL s AS STRING, l AS LONG, i AS LONG
    LOCAL hFile AS LONG, szFile AS ASCIIZ * %MAX_PATH
    LOCAL pID   AS DWORD, sBuff AS STRING
    LOCAL memcnt AS LONG
    
    FOR i = 1 TO 10
        
       GOSUB memtest_1
        
       ShowTOPWindow hPrnt
       
       GOSUB memtest_2
       
    NEXT i
    EXIT SUB
    
        memtest_1:
           INCR memcnt
           szFile    = "Process_memory_Statistics_" + FORMAT$(memcnt) + ".txt"

           hFile    = FREEFILE
           OPEN       szFile  FOR OUTPUT AS hFile
           PID      = GetCurrentProcessID
           sBUff    = "Process Memory Statistics for Process ID " & STR$(PID) & " on " & DATE$ & " at " & TIME$
           PRINT      #hFile, sBUff
           PRINT      #hFile,

           L        = GetProcessMemoryStatistics (s)

           sBUff    = "Process Memory Statistics 1"
           PRINT #hFile, sBuff
           PRINT #hFile, s
           PRINT #hFile,
        RETURN

        memtest_2:
           L        = GetProcessMemoryStatistics (s)
           sBUff    = "Process Memory Statistics 2"
           PRINT #hFile, sBuff
           PRINT #hFile, s
           PRINT #hFile,
           sBuff    = "END OF REPORT"
           PRINT #hFile, sBuff

           CLOSE hFile

           PID = SHELLExecute (GetDesktopWindow, "open", szFile, BYVAL %NULL, BYVAL %NULL, %SW_SHOW)
        RETURN
END SUB

DLL:

Code:

#COMPILE DLL "\Memtest.dll"
#DIM ALL

FUNCTION ShowTOPWindow(BYVAL hParent AS DWORD) EXPORT AS LONG
   
    ? "ShowTOPWindow() in DLL"
    
END FUNCTION

**Michael Mattias** · 20 Nov 2008, 08:24 AM

application, a windows-dialog situated in a DLL, more and more memory is lost each time you call the function in the DLL

That is a documented bug in prior versions and the workaround for non-upgraders is in the PowerBase forum.

Ooops, does not apply when statically linked.

My Bad.

**Gerhard Praetorius** · 20 Nov 2008, 09:16 AM

This is bad news. I have replaced almost all console-emelents in my apps by windows-dialogs (located in DLLs), and the console compiler will be obsolet for me within a few months. So it's not worth to buy the current version for the short remaining time. On the other hand I have this annoying memory leak...

**Michael Mattias** · 20 Nov 2008, 10:03 AM

I can't find it but I know there is a WinApi function which gives you a count of the current GDI objects owned by your application. That would be a handy thing for you in this case.

Maybe someone else remembers the name of that function.

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