Linux Skia: add an option to build a canvas from a provided memory buffer

skia/ext/bitmap_platform_device_linux.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "skia/ext/bitmap_platform_device_linux.h"
 
 #include <cairo/cairo.h>
 
 namespace skia {
 
@@ skipping 23 matching lines @@
   BitmapPlatformDeviceLinuxData(const BitmapPlatformDeviceLinuxData&);
   BitmapPlatformDeviceLinuxData& operator=(
       const BitmapPlatformDeviceLinuxData&);
 };
 
 // We use this static factory function instead of the regular constructor so
 // that we can create the pixel data before calling the constructor. This is
 // required so that we can call the base class' constructor with the pixel
 // data.
 BitmapPlatformDeviceLinux* BitmapPlatformDeviceLinux::Create(
-    int width, int height, bool is_opaque) {
-  cairo_surface_t* surface =
-      cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
-                                 width, height);
-
+    int width, int height, bool is_opaque, cairo_surface_t* surface) {
   SkBitmap bitmap;
   bitmap.setConfig(SkBitmap::kARGB_8888_Config, width, height,
                    cairo_image_surface_get_stride(surface));
   bitmap.setPixels(cairo_image_surface_get_data(surface));
   bitmap.setIsOpaque(is_opaque);
 
 #ifndef NDEBUG
   if (is_opaque) {
     bitmap.eraseARGB(255, 0, 255, 128);  // bright bluish green
   }
 #endif
 
   // The device object will take ownership of the graphics context.
   return new BitmapPlatformDeviceLinux
       (bitmap, new BitmapPlatformDeviceLinuxData(surface));
 }
 
+BitmapPlatformDeviceLinux* BitmapPlatformDeviceLinux::Create(
+    int width, int height, bool is_opaque) {
+  cairo_surface_t* surface =
+      cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
+                                 width, height);
+
+  return Create(width, height, is_opaque, surface);
+}
+
+BitmapPlatformDeviceLinux* BitmapPlatformDeviceLinux::Create(
+    int width, int height, bool is_opaque, uint8_t* data) {
+  cairo_surface_t* surface = cairo_image_surface_create_for_data(
+      data, CAIRO_FORMAT_ARGB32, width, height,
+      cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, width));
+
+  return Create(width, height, is_opaque, surface);
+}
+
 // The device will own the bitmap, which corresponds to also owning the pixel
 // data. Therefore, we do not transfer ownership to the SkDevice's bitmap.
 BitmapPlatformDeviceLinux::BitmapPlatformDeviceLinux(
     const SkBitmap& bitmap,
     BitmapPlatformDeviceLinuxData* data)
     : PlatformDeviceLinux(bitmap),
       data_(data) {
 }
 
 BitmapPlatformDeviceLinux::BitmapPlatformDeviceLinux(
@@ skipping 10 matching lines @@
   return data_->surface();
 }
 
 BitmapPlatformDeviceLinux& BitmapPlatformDeviceLinux::operator=(
     const BitmapPlatformDeviceLinux& other) {
   data_ = other.data_;
   return *this;
 }
 
 }  // namespace skia