Changeset 104501 in webkit

Timestamp:

Jan 9, 2012 3:53:36 PM (12 years ago)

Author:

commit-queue@webkit.org

Message:

[chromium win] Creating lots of temporary canvas contexts will crash.
​https://bugs.webkit.org/show_bug.cgi?id=68420

When using the skia port, the allocation of 2d canvas backing stores
no longer needs to be done through a platform API (GDI/CG) because
canvases now use skia for drawing text. Removing the allocation through
GDI on windows prevents resource exhaustion due to unreferenced canvases
that are awaiting garbage collection.

Patch by Justin Novosad <​junov@chromium.org> on 2012-01-09
Reviewed by Stephen White.

No new tests: Relying on existing canvas layout tests.

• html/HTMLCanvasElement.cpp:

(WebCore::HTMLCanvasElement::createImageBuffer):

• platform/graphics/ImageBuffer.h:
• platform/graphics/skia/ImageBufferSkia.cpp:

(WebCore::createNonPlatformCanvas):
(WebCore::ImageBuffer::ImageBuffer):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• html/HTMLCanvasElement.cpp (modified) (1 diff)
• platform/graphics/ImageBuffer.h (modified) (1 diff)
• platform/graphics/skia/ImageBufferSkia.cpp (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-01-09  Justin Novosad  <junov@chromium.org>
+
+        [chromium win] Creating lots of temporary canvas contexts will crash.
+        https://bugs.webkit.org/show_bug.cgi?id=68420
+
+        When using the skia port, the allocation of 2d canvas backing stores
+        no longer needs to be done through a platform API (GDI/CG) because
+        canvases now use skia for drawing text.  Removing the allocation through
+        GDI on windows prevents resource exhaustion due to unreferenced canvases
+        that are awaiting garbage collection.
+
+        Reviewed by Stephen White.
+
+        No new tests: Relying on existing canvas layout tests.
+
+        * html/HTMLCanvasElement.cpp:
+        (WebCore::HTMLCanvasElement::createImageBuffer):
+        * platform/graphics/ImageBuffer.h:
+        * platform/graphics/skia/ImageBufferSkia.cpp:
+        (WebCore::createNonPlatformCanvas):
+        (WebCore::ImageBuffer::ImageBuffer):
+
 2012-01-09  Avi Drissman  <avi@chromium.org>
 

trunk/Source/WebCore/html/HTMLCanvasElement.cpp

@@ -466 +466 @@
         return;
 
-    RenderingMode renderingMode = shouldAccelerate(bufferSize) ? Accelerated : Unaccelerated;
+    RenderingMode renderingMode = shouldAccelerate(bufferSize) ? Accelerated : 
+#if USE(SKIA)
+        UnacceleratedNonPlatformBuffer;
+#else
+        Unaccelerated;
+#endif
     m_imageBuffer = ImageBuffer::create(bufferSize, ColorSpaceDeviceRGB, renderingMode);
     if (!m_imageBuffer)

trunk/Source/WebCore/platform/graphics/ImageBuffer.h

@@ -60 +60 @@
     enum RenderingMode {
         Unaccelerated,
+        UnacceleratedNonPlatformBuffer, // Use plain memory allocation rather than platform API to allocate backing store.
         Accelerated
     };

trunk/Source/WebCore/platform/graphics/skia/ImageBufferSkia.cpp

@@ -94 +94 @@
 }
 
+static SkCanvas* createNonPlatformCanvas(const IntSize& size)
+{
+    SkCanvas* canvas = new SkCanvas();
+    canvas->setDevice(new SkDevice(SkBitmap::kARGB_8888_Config, size.width(), size.height()))->unref();
+    return canvas;
+}
+
 ImageBuffer::ImageBuffer(const IntSize& size, ColorSpace, RenderingMode renderingMode, bool& success)
     : m_data(size)
@@ -102 +109 @@
     if (renderingMode == Accelerated)
         canvas = adoptPtr(createAcceleratedCanvas(size, &m_data));
+    else if (renderingMode == UnacceleratedNonPlatformBuffer)
+        canvas = adoptPtr(createNonPlatformCanvas(size));
 
     if (!canvas)