Esme Povirk : gdiplus: Add a function to bracket HDC use.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: e29623bbeb46c498c881d545e8a6c408544e2089
URL:    https://gitlab.winehq.org/wine/wine/-/commit/e29623bbeb46c498c881d545e8a6c40...

Author: Esme Povirk <esme(a)codeweavers.com>
Date:   Thu May  2 13:44:54 2024 -0500

gdiplus: Add a function to bracket HDC use.

---

 dlls/gdiplus/gdiplus_private.h |  8 +++++++
 dlls/gdiplus/graphics.c        | 48 +++++++++++++++++++++++++++++++++---------
 2 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/dlls/gdiplus/gdiplus_private.h b/dlls/gdiplus/gdiplus_private.h
index 0b302a405ea..c3b516a9a2b 100644
--- a/dlls/gdiplus/gdiplus_private.h
+++ b/dlls/gdiplus/gdiplus_private.h
@@ -62,6 +62,8 @@ extern REAL units_scale(GpUnit from, GpUnit to, REAL dpi, BOOL printer_display);
 
 #define WineCoordinateSpaceGdiDevice ((GpCoordinateSpace)4)
 
+extern GpStatus gdi_dc_acquire(GpGraphics *graphics, HDC *hdc);
+extern void gdi_dc_release(GpGraphics *graphics, HDC hdc);
 extern GpStatus gdi_transform_acquire(GpGraphics *graphics);
 extern GpStatus gdi_transform_release(GpGraphics *graphics);
 extern GpStatus get_graphics_transform(GpGraphics *graphics, GpCoordinateSpace dst_space,
@@ -248,6 +250,7 @@ struct GpPen{
 struct GpGraphics{
     HDC hdc;
     HWND hwnd;
+    INT hdc_refs;
     BOOL owndc;
     BOOL alpha_hdc;
     BOOL printer_display;
@@ -658,6 +661,11 @@ static inline void image_unlock(GpImage *image)
     ReleaseSRWLockExclusive(&image->lock);
 }
 
+static inline BOOL has_gdi_dc(GpGraphics *graphics)
+{
+    return graphics->hdc != NULL;
+}
+
 static inline void set_rect(GpRectF *rect, REAL x, REAL y, REAL width, REAL height)
 {
     rect->X = x;
diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index 0727b63ed4f..cf54334ae2e 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -19,6 +19,7 @@
 #include <stdarg.h>
 #include <math.h>
 #include <limits.h>
+#include <assert.h>
 
 #include "windef.h"
 #include "winbase.h"
@@ -46,6 +47,25 @@ WINE_DEFAULT_DEBUG_CHANNEL(gdiplus);
 #define ANCHOR_WIDTH (2.0)
 #define MAX_ITERS (50)
 
+GpStatus gdi_dc_acquire(GpGraphics *graphics, HDC *hdc)
+{
+    if (graphics->hdc != NULL)
+    {
+        *hdc = graphics->hdc;
+        graphics->hdc_refs++;
+        return Ok;
+    }
+
+    *hdc = NULL;
+    return InvalidParameter;
+}
+
+void gdi_dc_release(GpGraphics *graphics, HDC hdc)
+{
+    assert(graphics->hdc_refs > 0);
+    graphics->hdc_refs--;
+}
+
 static GpStatus draw_driver_string(GpGraphics *graphics, GDIPCONST UINT16 *text, INT length,
                                    GDIPCONST GpFont *font, GDIPCONST GpStringFormat *format,
                                    GDIPCONST GpBrush *brush, GDIPCONST PointF *positions,
@@ -252,7 +272,7 @@ static HBRUSH create_gdi_brush(const GpBrush *brush, INT origin_x, INT origin_y)
     return gdibrush;
 }
 
-static INT prepare_dc(GpGraphics *graphics, GpPen *pen)
+static INT prepare_dc(GpGraphics *graphics, HDC hdc, GpPen *pen)
 {
     LOGBRUSH lb;
     HPEN gdipen;
@@ -261,9 +281,9 @@ static INT prepare_dc(GpGraphics *graphics, GpPen *pen)
     GpPointF pt[2];
     DWORD dash_array[MAX_DASHLEN];
 
-    save_state = SaveDC(graphics->hdc);
+    save_state = SaveDC(hdc);
 
-    EndPath(graphics->hdc);
+    EndPath(hdc);
 
     if(pen->unit == UnitPixel){
         width = pen->width;
@@ -311,15 +331,15 @@ static INT prepare_dc(GpGraphics *graphics, GpPen *pen)
         free_gdi_logbrush(&lb);
     }
 
-    SelectObject(graphics->hdc, gdipen);
+    SelectObject(hdc, gdipen);
 
     return save_state;
 }
 
-static void restore_dc(GpGraphics *graphics, INT state)
+static void restore_dc(GpGraphics *graphics, HDC hdc, INT state)
 {
-    DeleteObject(SelectObject(graphics->hdc, GetStockObject(NULL_PEN)));
-    RestoreDC(graphics->hdc, state);
+    DeleteObject(SelectObject(hdc, GetStockObject(NULL_PEN)));
+    RestoreDC(hdc, state);
 }
 
 static void round_points(POINT *pti, GpPointF *ptf, INT count)
@@ -2533,6 +2553,8 @@ GpStatus WINGDIPAPI GdipDeleteGraphics(GpGraphics *graphics)
     if(!graphics) return InvalidParameter;
     if(graphics->busy) return ObjectBusy;
 
+    assert(graphics->hdc_refs == 0);
+
     if (is_metafile_graphics(graphics))
     {
         stat = METAFILE_GraphicsDeleted((GpMetafile*)graphics->image);
@@ -3633,11 +3655,16 @@ GpStatus WINGDIPAPI GdipDrawLinesI(GpGraphics *graphics, GpPen *pen, GDIPCONST
 
 static GpStatus GDI32_GdipDrawPath(GpGraphics *graphics, GpPen *pen, GpPath *path)
 {
+    HDC hdc;
     INT save_state;
     GpStatus retval;
     HRGN hrgn=NULL;
 
-    save_state = prepare_dc(graphics, pen);
+    retval = gdi_dc_acquire(graphics, &hdc);
+    if (retval != Ok)
+        return retval;
+
+    save_state = prepare_dc(graphics, hdc, pen);
 
     retval = get_clip_hrgn(graphics, &hrgn);
 
@@ -3654,8 +3681,9 @@ static GpStatus GDI32_GdipDrawPath(GpGraphics *graphics, GpPen *pen, GpPath *pat
     gdi_transform_release(graphics);
 
 end:
-    restore_dc(graphics, save_state);
+    restore_dc(graphics, hdc, save_state);
     DeleteObject(hrgn);
+    gdi_dc_release(graphics, hdc);
 
     return retval;
 }
@@ -4069,7 +4097,7 @@ GpStatus WINGDIPAPI GdipDrawPath(GpGraphics *graphics, GpPen *pen, GpPath *path)
 
     if (is_metafile_graphics(graphics))
         retval = METAFILE_DrawPath((GpMetafile*)graphics->image, pen, path);
-    else if (!graphics->hdc || graphics->alpha_hdc || !brush_can_fill_path(pen->brush, FALSE))
+    else if (!has_gdi_dc(graphics) || graphics->alpha_hdc || !brush_can_fill_path(pen->brush, FALSE))
         retval = SOFTWARE_GdipDrawPath(graphics, pen, path);
     else
         retval = GDI32_GdipDrawPath(graphics, pen, path);