Deleaker detects resource leaks in StackOverflow answer

Recently, I need to capture the mouse cursor in my homebrew screen capture application, so my search sent me to StackOverflow’s Capture screen shot with mouse cursor. Out of curiosity, I ran Deleaker on it and it finds 2 HBITMAP leaks with every capture. My application captures mouse cursor 30 times per second, so the number of resource leaks are huge and can crash the application if running for more than 3 minutes.

CURSORINFO cursor = { sizeof(cursor) };
if (cursor.flags == CURSOR_SHOWING) {
    RECT rcWnd;
    ::GetWindowRect(hwnd, &rcWnd);
    ICONINFOEXW info = { sizeof(info) };
    ::GetIconInfoExW(cursor.hCursor, &info);
    const int x = cursor.ptScreenPos.x - rcWnd.left - rc.left 
                  - info.xHotspot;
    const int y = cursor.ptScreenPos.y -  - 
                  - info.yHotspot;
    BITMAP bmpCursor = {0};
    ::GetObject(info.hbmColor, sizeof(bmpCursor), &bmpCursor);
    ::DrawIconEx(hdcMem, x, y, cursor.hCursor, bmpCursor.bmWidth, 
        bmpCursor.bmHeight, 0, NULL, DI_NORMAL);

MSDN of GetIconInfoExW specifically notes GetIconInfoEx creates bitmaps for the hbmMask and hbmColor or members of ICONINFOEX. The calling application must manage these bitmaps and delete them when they are no longer necessary.

typedef struct _ICONINFOEXW {
  DWORD   cbSize;
  BOOL    fIcon;
  DWORD   xHotspot;
  DWORD   yHotspot;
  HBITMAP hbmMask;
  HBITMAP hbmColor;
  WORD    wResID;
  WCHAR   szModName[MAX_PATH];
  WCHAR   szResName[MAX_PATH];

So DeleteObject have to be called on these 2 members, as suggested by Deleaker.


One response to “Deleaker detects resource leaks in StackOverflow answer”

  1. fahadyounas555 Avatar

    hi i like post


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