From 5978175ef8a1932ea6386abc3d49231ac7955a5c Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Mon, 3 May 2021 19:31:46 +0800
Subject: [PATCH] handle zero width/height for BitBlt and StretchBlt

---
 src/newgdi/bitmap.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/newgdi/bitmap.c b/src/newgdi/bitmap.c
index 2e51167c..1702aa72 100644
--- a/src/newgdi/bitmap.c
+++ b/src/newgdi/bitmap.c
@@ -1112,6 +1112,8 @@ void GUIAPI BitBlt (HDC hsdc, int sx, int sy, int sw, int sh,
     sw += sx; sh += sy;
     coor_LP2SP (psdc, &sx, &sy);
     coor_LP2SP (psdc, &sw, &sh);
+    if (sw == sx) sw = sx + RECTW (psdc->DevRC);
+    if (sh == sy) sh = sy + RECTH (psdc->DevRC);
     SetRect (&srcOutput, sx, sy, sw, sh);
     NormalizeRect (&srcOutput);
     sx = srcOutput.left; sy = srcOutput.top;
@@ -1383,6 +1385,8 @@ void GUIAPI StretchBltLegacy (HDC hsdc, int sx, int sy, int sw, int sh,
     sw += sx; sh += sy;
     coor_LP2SP(psdc, &sx, &sy);
     coor_LP2SP(psdc, &sw, &sh);
+    if (sw == sx) sw = sx + RECTW (psdc->DevRC);
+    if (sh == sy) sh = sy + RECTH (psdc->DevRC);
     SetRect (&srcOutput, sx, sy, sw, sh);
     NormalizeRect (&srcOutput);
     sx = srcOutput.left; sy = srcOutput.top;
@@ -1391,6 +1395,8 @@ void GUIAPI StretchBltLegacy (HDC hsdc, int sx, int sy, int sw, int sh,
     dw += dx; dh += dy;
     coor_LP2SP (pddc, &dx, &dy);
     coor_LP2SP (pddc, &dw, &dh);
+    if (dw == dx) dw = dx + RECTW (pddc->DevRC);
+    if (dh == dy) dh = dy + RECTH (pddc->DevRC);
     SetRect (&dstOutput, dx, dy, dw, dh);
     NormalizeRect (&dstOutput);
     dx = dstOutput.left; dy = dstOutput.top;
@@ -1491,6 +1497,8 @@ void GUIAPI StretchBlt (HDC hsdc, int sx, int sy, int sw, int sh,
     sw += sx; sh += sy;
     coor_LP2SP(psdc, &sx, &sy);
     coor_LP2SP(psdc, &sw, &sh);
+    if (sw == sx) sw = sx + RECTW (psdc->DevRC);
+    if (sh == sy) sh = sy + RECTH (psdc->DevRC);
     SetRect (&srcOutput, sx, sy, sw, sh);
     NormalizeRect (&srcOutput);
     sx = srcOutput.left; sy = srcOutput.top;
@@ -1499,6 +1507,8 @@ void GUIAPI StretchBlt (HDC hsdc, int sx, int sy, int sw, int sh,
     dw += dx; dh += dy;
     coor_LP2SP (pddc, &dx, &dy);
     coor_LP2SP (pddc, &dw, &dh);
+    if (dw == dx) dw = dx + RECTW (pddc->DevRC);
+    if (dh == dy) dh = dy + RECTH (pddc->DevRC);
     SetRect (&dstOutput, dx, dy, dw, dh);
     NormalizeRect (&dstOutput);
     dx = dstOutput.left; dy = dstOutput.top;