Avoid unnecessary copies in ImageDecoder.

chrome/browser/image_decoder_browsertest.cc

 // Copyright 2015 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/browser/image_decoder.h"
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "chrome/grit/generated_resources.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "content/public/browser/browser_child_process_observer.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/child_process_data.h"
 #include "content/public/test/test_utils.h"
 #include "ui/base/l10n/l10n_util.h"
 
 using content::BrowserThread;
 
 namespace {
 
-std::string GetValidPngString() {
+std::vector<uint8_t> GetValidPngData() {
   // 1x1 PNG. Does not get much smaller than this.
   static const char kPngData[] =
       "\x89\x50\x4e\x47\x0d\x0a\x1a\x0a\x00\x00\x00\x0d\x49\x48\x44\x52"
       "\x00\x00\x00\x01\x00\x00\x00\x01\x08\x02\x00\x00\x00\x90\x77\x53"
       "\xde\x00\x00\x00\x0c\x49\x44\x41\x54\x08\xd7\x63\xf8\xff\xff\x3f"
       "\x00\x05\xfe\x02\xfe\xdc\xcc\x59\xe7\x00\x00\x00\x00\x49\x45\x4e"
       "\x44\xae\x42\x60\x82";
   // Need to specify the buffer size because it contains NULs.
-  return std::string(kPngData, sizeof(kPngData) - 1);
+  return std::vector<uint8_t>(kPngData, kPngData + sizeof(kPngData) - 1);
 }
 
 #if defined(OS_CHROMEOS)
 
-std::string GetValidJpgString() {
+std::vector<uint8_t> GetValidJpgData() {
   // 1x1 JPG created from the 1x1 PNG above.
   static const char kJpgData[] =
       "\xFF\xD8\xFF\xE0\x00\x10\x4A\x46\x49\x46\x00\x01\x01\x01\x00\x48"
       "\x00\x48\x00\x00\xFF\xDB\x00\x43\x00\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xDB\x00\x43\x01\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"
       "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xC0"
       "\x00\x11\x08\x00\x01\x00\x01\x03\x01\x22\x00\x02\x11\x01\x03\x11"
       "\x01\xFF\xC4\x00\x15\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00"
       "\x00\x00\x00\x00\x00\x00\x00\x03\xFF\xC4\x00\x14\x10\x01\x00\x00"
       "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xC4"
       "\x00\x14\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
       "\x00\x00\x00\x00\xFF\xC4\x00\x14\x11\x01\x00\x00\x00\x00\x00\x00"
       "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xDA\x00\x0C\x03\x01"
       "\x00\x02\x11\x03\x11\x00\x3F\x00\xA0\x00\xFF\xD9";
   // Need to specify the buffer size because it contains NULs.
-  return std::string(kJpgData, sizeof(kJpgData) - 1);
+  return std::vector<uint8_t>(kJpgData, kJpgData + sizeof(kJpgData) - 1);
 }
 
 #endif  // defined(OS_CHROMEOS)
 
 class TestImageRequest : public ImageDecoder::ImageRequest {
  public:
   explicit TestImageRequest(const base::Closure& quit_closure)
       : decode_succeeded_(false),
         quit_closure_(quit_closure),
         quit_called_(false) {
@@ skipping 88 matching lines @@
 
 }  // namespace
 
 class ImageDecoderBrowserTest : public InProcessBrowserTest {
 };
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, Basic) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::Start(&test_request, std::string());
+  ImageDecoder::Start(&test_request, std::vector<uint8_t>());
   runner->Run();
   EXPECT_FALSE(test_request.decode_succeeded());
 }
 
 #if defined(OS_CHROMEOS)
 
+IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, BasicDecodeWithOptionsString) {
+  scoped_refptr<content::MessageLoopRunner> runner =
+      new content::MessageLoopRunner;
+  TestImageRequest test_request(runner->QuitClosure());
+  const std::vector<uint8_t> data = GetValidPngData();
+  ImageDecoder::StartWithOptions(&test_request,
+                                 std::string(data.begin(), data.end()),
+                                 ImageDecoder::ROBUST_PNG_CODEC,
+                                 false /* shrink_to_fit */);
+  runner->Run();
+  EXPECT_TRUE(test_request.decode_succeeded());
+}
+
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, RobustJpegCodecWithJpegData) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::StartWithOptions(&test_request, GetValidJpgString(),
+  ImageDecoder::StartWithOptions(&test_request, GetValidJpgData(),
                                  ImageDecoder::ROBUST_JPEG_CODEC,
                                  false /* shrink_to_fit */);
   runner->Run();
   EXPECT_TRUE(test_request.decode_succeeded());
 }
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, RobustJpegCodecWithPngData) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::StartWithOptions(&test_request, GetValidPngString(),
+  ImageDecoder::StartWithOptions(&test_request, GetValidPngData(),
                                  ImageDecoder::ROBUST_JPEG_CODEC,
                                  false /* shrink_to_fit */);
   runner->Run();
   // Should fail with PNG data because only JPEG data is allowed.
   EXPECT_FALSE(test_request.decode_succeeded());
 }
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, RobustPngCodecWithPngData) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::StartWithOptions(&test_request, GetValidPngString(),
+  ImageDecoder::StartWithOptions(&test_request, GetValidPngData(),
                                  ImageDecoder::ROBUST_PNG_CODEC,
                                  false /* shrink_to_fit */);
   runner->Run();
   EXPECT_TRUE(test_request.decode_succeeded());
 }
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, RobustPngCodecWithJpegData) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::StartWithOptions(&test_request, GetValidJpgString(),
+  ImageDecoder::StartWithOptions(&test_request, GetValidJpgData(),
                                  ImageDecoder::ROBUST_PNG_CODEC,
                                  false /* shrink_to_fit */);
   runner->Run();
   // Should fail with JPEG data because only PNG data is allowed.
   EXPECT_FALSE(test_request.decode_succeeded());
 }
 
 #endif  // defined(OS_CHROMEOS)
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, BasicDecode) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::Start(&test_request, GetValidPngString());
+  ImageDecoder::Start(&test_request, GetValidPngData());
   runner->Run();
   EXPECT_TRUE(test_request.decode_succeeded());
 }
+
+IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, BasicDecodeString) {
+  scoped_refptr<content::MessageLoopRunner> runner =
+      new content::MessageLoopRunner;
+  TestImageRequest test_request(runner->QuitClosure());
+  const std::vector<uint8_t> data = GetValidPngData();
+  ImageDecoder::Start(&test_request, std::string(data.begin(), data.end()));
+  runner->Run();
+  EXPECT_TRUE(test_request.decode_succeeded());
+}
 
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, StartAndDestroy) {
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   std::unique_ptr<TestImageRequest> test_request(
       new TestImageRequest(runner->QuitClosure()));
-  ImageDecoder::Start(test_request.get(), std::string());
+  ImageDecoder::Start(test_request.get(), std::vector<uint8_t>());
   test_request.reset();
   runner->Run();
 }
 
 // Killing the utility process counts as a crash. Thus the request fails.
 // If ImageDecoder did not handle the crash properly, the request never finishes
 // and this test would hang.
 // Note: This test is inherently racy because KillProcessObserver lives on the
 // UI thread but ImageDecoder does its work mainly on the IO thread. So the test
 // checks for both possible valid outcomes.
 IN_PROC_BROWSER_TEST_F(ImageDecoderBrowserTest, StartAndKillProcess) {
   KillProcessObserver observer;
   scoped_refptr<content::MessageLoopRunner> runner =
       new content::MessageLoopRunner;
   TestImageRequest test_request(runner->QuitClosure());
-  ImageDecoder::Start(&test_request, GetValidPngString());
+  ImageDecoder::Start(&test_request, GetValidPngData());
   runner->Run();
   if (!test_request.decode_succeeded()) {
     // The UI thread won the race. Make sure the utility process did get killed.
     EXPECT_TRUE(observer.did_kill());
   }
   // Else the IO thread won the race and the image got decoded. Oh well.
 }