[Bug 1534] New: CreateBitmap is supposed to return the stock object

[Wine Bugs]

http://bugs.winehq.com/show_bug.cgi?id=1534

           Summary: CreateBitmap is supposed to return the stock object
           Product: Wine
           Version: unspecified
          Platform: Other
        OS/Version: other
            Status: UNCONFIRMED
          Severity: minor
          Priority: P2
         Component: wine-gdi
        AssignedTo: wine-bugs(a)winehq.com
        ReportedBy: pete_a90(a)hotmail.com


Note, I don't have wine but I use the source code as a reference because msdn 
is terrible at times. I noticed that the author of CreateCompatibleBitmap and 
CreateBitmap (and CreateBitmapIndirect too but that calls CreateBitmap 
directly) misinterpreted the gdi documentation. It returns *the* (as in 
GetStockObject(DEFALT_BITMAP) in wine) handle to a 1x1
monochrome bitmap if the width or height is 0. Here is some test code that I 
wrote in windows that verifies this is true:



#define WIN32_LEAN_AND_MEAN
#include <windows.h>

int main()
{
	HDC screenDC = GetDC(0);
	HDC hdc = CreateCompatibleDC(screenDC);

// all of these are the stock (in wine) monochrome bitmap
	HBITMAP bm = CreateCompatibleBitmap(hdc, 0, 0);
	HBITMAP bm1 = CreateCompatibleBitmap(hdc, 0, 0);
	HBITMAP bm4 = CreateBitmap(0, 1, 0, 0, 0);
	HBITMAP bm5 = CreateDiscardableBitmap(hdc, 0, 0);
	HBITMAP curObj = (HBITMAP)GetCurrentObject(hdc, OBJ_BITMAP);

	HBITMAP bm2 = CreateCompatibleBitmap(hdc, 1, 1);
	HBITMAP bm3 = CreateBitmap(1, 1, 1, 1, 0);

	HBITMAP old = (HBITMAP)SelectObject(hdc, (HGDIOBJ)bm2);
	SelectObject(hdc, (HGDIOBJ)old);

// old == the stock monochrome bitmaps above

	{
		HBITMAP screenBM = (HBITMAP)GetCurrentObject(screenDC, 
OBJ_BITMAP);
// weird: screenBM != bm
		BITMAP bitmap1;

		int ret = GetObject(screenBM, 0, 0); // returns sizeof(BITMAP)

		BITMAP bitmap2;

		memset(&bitmap1, 0xDA, sizeof(bitmap1));
		ret = GetObject(screenBM, ret, &bitmap1);
// ret = 0, doesn't touch bitmap1 at all.

		ret = GetObject(bm, sizeof(bitmap2), &bitmap2);
// ret = 18, bitmap2 is filled in with the monochrome bitmap info
	}

	DeleteObject(bm);
	DeleteObject(bm1);
	DeleteObject(bm2);
	DeleteObject(bm3);
	DeleteObject(bm4);
	DeleteObject(bm5);

	DeleteDC(hdc);
	ReleaseDC(0, screenDC);

	return 0;
}



Looks like an easy fix though (don't quote me on that since I don't use linux 
and I don't have a local copy of the code [sorry for no path either]):

In CreateCompatibleBitmap replace the following:

/* MS doc says if width or height is 0, return 1-by-1 pixel, monochrome bitmap 
*/
if (!width || !height)
  hbmpRet = CreateBitmap( 1, 1, 1, 1, NULL );
else
  hbmpRet = CreateBitmap( width, height, 1, dc->bitsPerPixel, NULL );

with just:

  hbmpRet = CreateBitmap( width, height, 1, dc->bitsPerPixel, NULL );

and in CreateBitmap replace:

if (!height || !width)
{
  height = 1;
  width  = 1;
  planes = 1;
  bpp    = 1;
}

with:

if (!height || !width)
  return GetStockObject(DEFAULT_BITMAP);

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