Convert the utility process image decoder into a Mojo service.

chrome/utility/image_decoder_impl_unittest.cc

+// Copyright 2016 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 "chrome/utility/image_decoder_impl.h"
+
+#include <vector>
+
+#include "base/bind.h"
+#include "ipc/ipc_channel.h"
+#include "skia/public/type_converters.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/gfx/codec/jpeg_codec.h"
+
+namespace mojom {
+
+namespace {
+
+bool CreateJPEGImage(int width,
+                     int height,
+                     SkColor color,
+                     std::vector<unsigned char>* output) {
+  SkBitmap bitmap;
+  bitmap.allocN32Pixels(width, height);
+  bitmap.eraseColor(color);
+
+  const int kQuality = 50;
+  if (!gfx::JPEGCodec::Encode(
+          static_cast<const unsigned char*>(bitmap.getPixels()),
+          gfx::JPEGCodec::FORMAT_SkBitmap, width, height,
+          static_cast<int>(bitmap.rowBytes()), kQuality, output)) {
+    LOG(ERROR) << "Unable to encode " << width << "x" << height << " bitmap";
+    return false;
+  }
+  return true;
+}
+
+class Request {
+ public:
+  explicit Request(ImageDecoderImpl* decoder) : decoder_(decoder) {}
+
+  void DecodeImage(const std::vector<unsigned char>& image, bool shrink) {
+    decoder_->DecodeImage(
+        mojo::Array<uint8_t>::From(image), ImageCodec::DEFAULT,
+        shrink, base::Bind(&Request::OnRequestDone, base::Unretained(this)));
+  }
+
+  const skia::mojom::BitmapPtr& bitmap() const { return bitmap_; }
+
+ private:
+  void OnRequestDone(skia::mojom::BitmapPtr result_image) {
+    bitmap_ = std::move(result_image);
+  }
+
+  ImageDecoderImpl* decoder_;
+  skia::mojom::BitmapPtr bitmap_;
+};
+
+}  // namespace
+
+// Test that DecodeImage() doesn't return image message > (max message size)
+TEST(ImageDecoderImplTest, DecodeImageSizeLimit) {
+  // Using actual limit generates 14000 x 9400 images, which causes the test to
+  // timeout.  We test with a smaller limit for efficiency.
+  const size_t kTestMessageSize = IPC::Channel::kMaximumMessageSize / 1024;
+
+  ImageDecoderImpl decoder(kTestMessageSize);
+
+  // Approx max height for 3:2 image that will fit in IPC message;
+  // 1.5 for width/height ratio, 4 for bytes/pixel
+  int max_height_for_msg = sqrt(kTestMessageSize / (1.5 * 4));
+  int base_msg_size = sizeof(skia::mojom::Bitmap::Data_);
+
+  // Sizes which should trigger dimension-halving 0, 1 and 2 times
+  int heights[] = {max_height_for_msg - 10,
+                   max_height_for_msg + 10,
+                   2 * max_height_for_msg + 10};
+  int widths[] = {heights[0] * 3 / 2, heights[1] * 3 / 2, heights[2] * 3 / 2};
+  for (size_t i = 0; i < arraysize(heights); i++) {
+    std::vector<unsigned char> jpg;
+    ASSERT_TRUE(CreateJPEGImage(widths[i], heights[i], SK_ColorRED, &jpg));
+
+    Request request(&decoder);
+    request.DecodeImage(jpg, true);
+    ASSERT_FALSE(request.bitmap().is_null());
+    SkBitmap bitmap = request.bitmap().To<SkBitmap>();
+
+    // Check that image has been shrunk appropriately
+    EXPECT_LT(bitmap.computeSize64() + base_msg_size,
+              static_cast<int64_t>(kTestMessageSize));
+// Android does its own image shrinking for memory conservation deeper in
+// the decode, so more specific tests here won't work.
+#if !defined(OS_ANDROID)
+    EXPECT_EQ(widths[i] >> i, bitmap.width());
+    EXPECT_EQ(heights[i] >> i, bitmap.height());
+
+    // Check that if resize not requested and image exceeds IPC size limit,
+    // an empty image is returned
+    if (heights[i] > max_height_for_msg) {
+      Request request(&decoder);
+      request.DecodeImage(jpg, false);
+      EXPECT_TRUE(request.bitmap().is_null());
+    }
+#endif
+  }
+}
+
+TEST(ImageDecoderImplTest, DecodeImageFailed) {
+  ImageDecoderImpl decoder(IPC::Channel::kMaximumMessageSize);
+
+  // The "jpeg" is just some "random" data;
+  const char kRandomData[] = "u gycfy7xdjkhfgui bdui ";
+  std::vector<unsigned char> jpg(kRandomData,
+                                 kRandomData + sizeof(kRandomData));
+
+  Request request(&decoder);
+  request.DecodeImage(jpg, false);
+  EXPECT_TRUE(request.bitmap().is_null());
+}
+
+}  // namespace mojom