[PATCH 0/5] MR5593: gdiplus: Start bracketing Graphics HDC uses.

[Esme Povirk (＠madewokherd)]

This is the first part of a longer series of commits that can be found here: https://gitlab.winehq.org/madewokherd/wine/-/tree/getdc-wip?ref_type=heads

The eventual goal is to no longer store gdi32 handles, which are a limited resource, on gdiplus objects, except when absolutely necessary. In particular, Graphics objects created from an HWND do not need to store an HDC (GetDC/ReleaseDC theoretically caches those and works just fine), and Bitmap objects with a gdi32-compatible format shouldn't store an HBITMAP or HDC. These changes revealed some other bugs in bitmap and linecap code, which I've also fixed in order to keep the tests working.

[PATCH 1/5] gdiplus: Add a function to bracket HDC use.

[Esme Povirk]

From: Esme Povirk

---
 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);

[PATCH 2/5] gdiplus: Bracket HDC use in gdi_alpha_blend.

[Esme Povirk]

From: Esme Povirk

---
 dlls/gdiplus/graphics.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index cf54334ae2e..3c00eddddf4 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -362,9 +362,14 @@ static void round_points(POINT *pti, GpPointF *ptf, INT count)
 static void gdi_alpha_blend(GpGraphics *graphics, INT dst_x, INT dst_y, INT dst_width, INT dst_height,
                             HDC hdc, INT src_x, INT src_y, INT src_width, INT src_height)
 {
+    HDC dst_hdc;
     CompositingMode comp_mode;
-    INT technology = GetDeviceCaps(graphics->hdc, TECHNOLOGY);
-    INT shadeblendcaps  = GetDeviceCaps(graphics->hdc, SHADEBLENDCAPS);
+    INT technology, shadeblendcaps;
+
+    gdi_dc_acquire(graphics, &dst_hdc);
+
+    technology = GetDeviceCaps(dst_hdc, TECHNOLOGY);
+    shadeblendcaps  = GetDeviceCaps(dst_hdc, SHADEBLENDCAPS);

GdipGetCompositingMode(graphics, &comp_mode);

@@ -373,7 +378,7 @@ static void gdi_alpha_blend(GpGraphics *graphics, INT dst_x, INT dst_y, INT dst_
     {
         TRACE("alpha blending not supported by device, fallback to StretchBlt\n");

-        StretchBlt(graphics->hdc, dst_x, dst_y, dst_width, dst_height,
+        StretchBlt(dst_hdc, dst_x, dst_y, dst_width, dst_height,
                    hdc, src_x, src_y, src_width, src_height, SRCCOPY);
     }
     else
@@ -385,9 +390,11 @@ static void gdi_alpha_blend(GpGraphics *graphics, INT dst_x, INT dst_y, INT dst_
         bf.SourceConstantAlpha = 255;
         bf.AlphaFormat = AC_SRC_ALPHA;

-        GdiAlphaBlend(graphics->hdc, dst_x, dst_y, dst_width, dst_height,
+        GdiAlphaBlend(dst_hdc, dst_x, dst_y, dst_width, dst_height,
                       hdc, src_x, src_y, src_width, src_height, bf);
     }
+
+    gdi_dc_release(graphics, dst_hdc);
 }

static GpStatus get_clip_hrgn(GpGraphics *graphics, HRGN *hrgn)

[PATCH 3/5] gdiplus: Bracket HDC use in alpha_blend_pixels_hrgn.

[Esme Povirk]

From: Esme Povirk

---
 dlls/gdiplus/graphics.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index 3c00eddddf4..78e3b07222d 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -591,28 +591,39 @@ static GpStatus alpha_blend_pixels_hrgn(GpGraphics *graphics, INT dst_x, INT dst
     }
     else
     {
+        HDC hdc;
         HRGN hrgn;
         int save;

+        stat = gdi_dc_acquire(graphics, &hdc);
+
+        if (stat != Ok)
+            return stat;
+
         stat = get_clip_hrgn(graphics, &hrgn);

if (stat != Ok)
+        {
+            gdi_dc_release(graphics, hdc);
             return stat;
+        }

-        save = SaveDC(graphics->hdc);
+        save = SaveDC(hdc);

-        ExtSelectClipRgn(graphics->hdc, hrgn, RGN_COPY);
+        ExtSelectClipRgn(hdc, hrgn, RGN_COPY);

if (hregion)
-            ExtSelectClipRgn(graphics->hdc, hregion, RGN_AND);
+            ExtSelectClipRgn(hdc, hregion, RGN_AND);

stat = alpha_blend_hdc_pixels(graphics, dst_x, dst_y, src, src_width,
             src_height, src_stride, fmt);

-        RestoreDC(graphics->hdc, save);
+        RestoreDC(hdc, save);

DeleteObject(hrgn);

+        gdi_dc_release(graphics, hdc);
+
         return stat;
     }
 }

[PATCH 4/5] gdiplus: Bracket hdc use in brush_fill_path.

[Esme Povirk]

From: Esme Povirk

---
 dlls/gdiplus/graphics.c | 30 +++++++++++++++++++-----------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index 78e3b07222d..48d425341f8 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -1150,7 +1150,13 @@ static BOOL brush_can_fill_path(GpBrush *brush, BOOL is_fill)

static GpStatus brush_fill_path(GpGraphics *graphics, GpBrush *brush)
 {
-    GpStatus status = Ok;
+    HDC hdc;
+    GpStatus status;
+
+    status = gdi_dc_acquire(graphics, &hdc);
+    if (status != Ok)
+        return status;
+
     switch (brush->bt)
     {
     case BrushTypeSolidColor:
@@ -1163,27 +1169,27 @@ static GpStatus brush_fill_path(GpGraphics *graphics, GpBrush *brush)
             RECT rc;
             /* partially transparent fill */

-            if (!SelectClipPath(graphics->hdc, RGN_AND))
+            if (!SelectClipPath(hdc, RGN_AND))
             {
                 status = GenericError;
                 DeleteObject(bmp);
                 break;
             }
-            if (GetClipBox(graphics->hdc, &rc) != NULLREGION)
+            if (GetClipBox(hdc, &rc) != NULLREGION)
             {
-                HDC hdc = CreateCompatibleDC(NULL);
+                HDC src_hdc = CreateCompatibleDC(NULL);

-                if (!hdc)
+                if (!src_hdc)
                 {
                     status = OutOfMemory;
                     DeleteObject(bmp);
                     break;
                 }

-                SelectObject(hdc, bmp);
+                SelectObject(src_hdc, bmp);
                 gdi_alpha_blend(graphics, rc.left, rc.top, rc.right - rc.left, rc.bottom - rc.top,
-                                hdc, 0, 0, 1, 1);
-                DeleteDC(hdc);
+                                src_hdc, 0, 0, 1, 1);
+                DeleteDC(src_hdc);
             }

DeleteObject(bmp);
@@ -1202,14 +1208,16 @@ static GpStatus brush_fill_path(GpGraphics *graphics, GpBrush *brush)
             break;
         }

-        old_brush = SelectObject(graphics->hdc, gdibrush);
-        FillPath(graphics->hdc);
-        SelectObject(graphics->hdc, old_brush);
+        old_brush = SelectObject(hdc, gdibrush);
+        FillPath(hdc);
+        SelectObject(hdc, old_brush);
         DeleteObject(gdibrush);
         break;
     }
     }

+    gdi_dc_release(graphics, hdc);
+
     return status;
 }

[PATCH 5/5] gdiplus: Bracket HDC use in draw_cap.

[Esme Povirk]

From: Esme Povirk

---
 dlls/gdiplus/graphics.c | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/dlls/gdiplus/graphics.c b/dlls/gdiplus/graphics.c
index 48d425341f8..bd77758eb51 100644
--- a/dlls/gdiplus/graphics.c
+++ b/dlls/gdiplus/graphics.c
@@ -1667,6 +1667,7 @@ static GpStatus brush_fill_pixels(GpGraphics *graphics, GpBrush *brush,
 static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL size,
     const GpCustomLineCap *custom, REAL x1, REAL y1, REAL x2, REAL y2)
 {
+    HDC hdc;
     HGDIOBJ oldbrush = NULL, oldpen = NULL;
     GpMatrix matrix;
     HBRUSH brush = NULL;
@@ -1682,6 +1683,8 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s
     if((x1 == x2) && (y1 == y2))
         return;

+    gdi_dc_acquire(graphics, &hdc);
+
     theta = gdiplus_atan2(y2 - y1, x2 - x1);

customstroke = (cap == LineCapCustom) && custom && (!custom->fill);
@@ -1693,8 +1696,8 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s
         pen = ExtCreatePen(PS_GEOMETRIC | PS_SOLID | PS_ENDCAP_FLAT |
                            PS_JOIN_MITER, 1, &lb, 0,
                            NULL);
-        oldbrush = SelectObject(graphics->hdc, brush);
-        oldpen = SelectObject(graphics->hdc, pen);
+        oldbrush = SelectObject(hdc, brush);
+        oldpen = SelectObject(hdc, pen);
     }

switch(cap){
@@ -1729,7 +1732,7 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s

round_points(pt, ptf, 4);

-            Polygon(graphics->hdc, pt, 4);
+            Polygon(hdc, pt, 4);

break;
         case LineCapArrowAnchor:
@@ -1754,7 +1757,7 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s

round_points(pt, ptf, 3);

-            Polygon(graphics->hdc, pt, 3);
+            Polygon(hdc, pt, 3);

break;
         case LineCapRoundAnchor:
@@ -1769,7 +1772,7 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s

round_points(pt, ptf, 2);

-            Ellipse(graphics->hdc, pt[0].x, pt[0].y, pt[1].x, pt[1].y);
+            Ellipse(hdc, pt[0].x, pt[0].y, pt[1].x, pt[1].y);

break;
         case LineCapTriangle:
@@ -1792,7 +1795,7 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s

round_points(pt, ptf, 3);

-            Polygon(graphics->hdc, pt, 3);
+            Polygon(hdc, pt, 3);

break;
         case LineCapRound:
@@ -1815,7 +1818,7 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s

round_points(pt, ptf, 4);

-            Pie(graphics->hdc, pt[0].x, pt[0].y, pt[1].x, pt[1].y, pt[2].x,
+            Pie(hdc, pt[0].x, pt[0].y, pt[1].x, pt[1].y, pt[2].x,
                 pt[2].y, pt[3].x, pt[3].y);

break;
@@ -1855,13 +1858,13 @@ static void draw_cap(GpGraphics *graphics, COLORREF color, GpLineCap cap, REAL s
                 tp[i] = convert_path_point_type(custom->pathdata.Types[i]);

if(custom->fill){
-                BeginPath(graphics->hdc);
-                PolyDraw(graphics->hdc, custpt, tp, count);
-                EndPath(graphics->hdc);
-                StrokeAndFillPath(graphics->hdc);
+                BeginPath(hdc);
+                PolyDraw(hdc, custpt, tp, count);
+                EndPath(hdc);
+                StrokeAndFillPath(hdc);
             }
             else
-                PolyDraw(graphics->hdc, custpt, tp, count);
+                PolyDraw(hdc, custpt, tp, count);

custend:
             free(custptf);
@@ -1873,11 +1876,13 @@ custend:
     }

if(!customstroke){
-        SelectObject(graphics->hdc, oldbrush);
-        SelectObject(graphics->hdc, oldpen);
+        SelectObject(hdc, oldbrush);
+        SelectObject(hdc, oldpen);
         DeleteObject(brush);
         DeleteObject(pen);
     }
+
+    gdi_dc_release(graphics, hdc);
 }

/* Shortens the line by the given percent by changing x2, y2.