From 8955c86721b67686266c0a9d3fbb16a29ac4939a Mon Sep 17 00:00:00 2001
From: Matt Woodrow <mwoodrow@mozilla.com>
Date: Tue, 1 Jul 2014 17:52:51 +1200
Subject: [PATCH] Bug 997304 - Copy the image data if it's not a suitable size
 for cairo. r=Bas

---
 gfx/2d/DrawTargetCairo.cpp | 82 +++++++++++++++++++-------------------
 gfx/2d/DrawTargetCairo.h   |  1 +
 2 files changed, 42 insertions(+), 41 deletions(-)

diff --git a/gfx/2d/DrawTargetCairo.cpp b/gfx/2d/DrawTargetCairo.cpp
index 57eb3de59ab8..d82c96219414 100644
--- a/gfx/2d/DrawTargetCairo.cpp
+++ b/gfx/2d/DrawTargetCairo.cpp
@@ -133,6 +133,36 @@ ReleaseData(void* aData)
   static_cast<DataSourceSurface*>(aData)->Release();
 }
 
+cairo_surface_t*
+CopyToImageSurface(unsigned char *aData,
+                   const IntSize &aSize,
+                   int32_t aStride,
+                   SurfaceFormat aFormat)
+{
+  cairo_surface_t* surf = cairo_image_surface_create(GfxFormatToCairoFormat(aFormat),
+                                                     aSize.width,
+                                                     aSize.height);
+  // In certain scenarios, requesting larger than 8k image fails.  Bug 803568
+  // covers the details of how to run into it, but the full detailed
+  // investigation hasn't been done to determine the underlying cause.  We
+  // will just handle the failure to allocate the surface to avoid a crash.
+  if (cairo_surface_status(surf)) {
+    return nullptr;
+  }
+
+  unsigned char* surfData = cairo_image_surface_get_data(surf);
+  int surfStride = cairo_image_surface_get_stride(surf);
+  int32_t pixelWidth = BytesPerPixel(aFormat);
+
+  for (int32_t y = 0; y < aSize.height; ++y) {
+    memcpy(surfData + y * surfStride,
+           aData + y * aStride,
+           aSize.width * pixelWidth);
+  }
+  cairo_surface_mark_dirty(surf);
+  return surf;
+}
+
 /**
  * Returns cairo surface for the given SourceSurface.
  * If possible, it will use the cairo_surface associated with aSurface,
@@ -177,7 +207,16 @@ GetCairoSurfaceForSourceSurface(SourceSurface *aSurface, bool aExistingOnly = fa
   // investigation hasn't been done to determine the underlying cause.  We
   // will just handle the failure to allocate the surface to avoid a crash.
   if (cairo_surface_status(surf)) {
-    cairo_surface_destroy(surf);
+    if (cairo_surface_status(surf) == CAIRO_STATUS_INVALID_STRIDE) {
+      // If we failed because of an invalid stride then copy into
+      // a new surface with a stride that cairo chooses. No need to
+      // set user data since we're not dependent on the original
+      // data.
+      return CopyToImageSurface(data->GetData(),
+                                data->GetSize(),
+                                data->Stride(),
+                                data->GetFormat());
+    }
     return nullptr;
   }
 
@@ -1056,52 +1095,13 @@ DrawTargetCairo::CreateFilter(FilterType aType)
   return FilterNodeSoftware::Create(aType);
 }
 
-/**
- * Copies pixel data from aData into aSurface; aData must have the dimensions
- * given in aSize, with a stride of aStride bytes and aPixelWidth bytes per pixel
- */
-static void
-CopyDataToCairoSurface(cairo_surface_t* aSurface,
-                       unsigned char *aData,
-                       const IntSize &aSize,
-                       int32_t aStride,
-                       int32_t aPixelWidth)
-{
-  unsigned char* surfData = cairo_image_surface_get_data(aSurface);
-  int surfStride = cairo_image_surface_get_stride(aSurface);
-  // In certain scenarios, requesting larger than 8k image fails.  Bug 803568
-  // covers the details of how to run into it, but the full detailed
-  // investigation hasn't been done to determine the underlying cause.  We
-  // will just handle the failure to allocate the surface to avoid a crash.
-  if (!surfData) {
-    return;
-  }
-  for (int32_t y = 0; y < aSize.height; ++y) {
-    memcpy(surfData + y * surfStride,
-           aData + y * aStride,
-           aSize.width * aPixelWidth);
-  }
-  cairo_surface_mark_dirty(aSurface);
-}
-
 TemporaryRef<SourceSurface>
 DrawTargetCairo::CreateSourceSurfaceFromData(unsigned char *aData,
                                              const IntSize &aSize,
                                              int32_t aStride,
                                              SurfaceFormat aFormat) const
 {
-  cairo_surface_t* surf = cairo_image_surface_create(GfxFormatToCairoFormat(aFormat),
-                                                     aSize.width,
-                                                     aSize.height);
-  // In certain scenarios, requesting larger than 8k image fails.  Bug 803568
-  // covers the details of how to run into it, but the full detailed
-  // investigation hasn't been done to determine the underlying cause.  We
-  // will just handle the failure to allocate the surface to avoid a crash.
-  if (cairo_surface_status(surf)) {
-    return nullptr;
-  }
-
-  CopyDataToCairoSurface(surf, aData, aSize, aStride, BytesPerPixel(aFormat));
+  cairo_surface_t* surf = CopyToImageSurface(aData, aSize, aStride, aFormat);
 
   RefPtr<SourceSurfaceCairo> source_surf = new SourceSurfaceCairo(surf, aSize, aFormat);
   cairo_surface_destroy(surf);
diff --git a/gfx/2d/DrawTargetCairo.h b/gfx/2d/DrawTargetCairo.h
index 46ad2902ee4b..c4977841c736 100644
--- a/gfx/2d/DrawTargetCairo.h
+++ b/gfx/2d/DrawTargetCairo.h
@@ -198,6 +198,7 @@ private: // methods
   // If the current operator is "source" then clear the destination before we
   // draw into it, to simulate the effect of an unbounded source operator.
   void ClearSurfaceForUnboundedSource(const CompositionOp &aOperator);
+
 private: // data
   cairo_t* mContext;
   cairo_surface_t* mSurface;