windowscodecs: Fix non-zero alpha detection in ImagingFactory_CreateBitmapFromHICON.

Increment pixel pointer for every *pixel*, not every *stride*. Signed-off-by: Jinoh Kang <jinoh.kang.kr@gmail.com>

windowscodecs: Fix non-zero alpha detection in ImagingFactory_CreateBitmapFromHICON.
e6155827 · Jinoh Kang · Alexandre Julliard · 29dd8444 · e6155827
Commit e6155827 authored Jun 28, 2022 by Jinoh Kang Committed by Alexandre Julliard Jun 29, 2022
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imgfactory.c dlls/windowscodecs/imgfactory.c +4 -6

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--- a/dlls/windowscodecs/imgfactory.c
+++ b/dlls/windowscodecs/imgfactory.c
@@ -901,12 +901,11 @@ static HRESULT WINAPI ImagingFactory_CreateBitmapFromHICON(IWICImagingFactory2 *
        if (bm.bmBitsPixel == 32)
        {
            /* If any pixel has a non-zero alpha, ignore hbmMask */
-            bits = (DWORD *)buffer;
-            for (x = 0; x < width && !has_alpha; x++, bits++)
+            DWORD *ptr = (DWORD *)buffer;
+            DWORD *end = ptr + width * height;
+            while (ptr != end)
            {
-                for (y = 0; y < height; y++)
-                {
-                    if (*bits & 0xff000000)
+                if (*ptr++ & 0xff000000)
                {
                    has_alpha = TRUE;
                    break;
@@ -914,7 +913,6 @@ static HRESULT WINAPI ImagingFactory_CreateBitmapFromHICON(IWICImagingFactory2 *
            }
        }
    }
-    }
    else
        GetDIBits(hdc, info.hbmMask, 0, height, buffer, &bi, DIB_RGB_COLORS);