Large wallpaper decoding in utility process

chrome/utility/chrome_content_utility_client.cc

 // Copyright (c) 2012 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/chrome_content_utility_client.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "chrome/common/chrome_utility_messages.h"
 #include "chrome/common/safe_browsing/zip_analyzer.h"
 #include "chrome/utility/chrome_content_utility_ipc_whitelist.h"
 #include "chrome/utility/utility_message_handler.h"
 #include "chrome/utility/web_resource_unpacker.h"
 #include "content/public/child/image_decoder_utils.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/utility/utility_thread.h"
 #include "courgette/courgette.h"
 #include "courgette/third_party/bsdiff.h"
+#include "ipc/ipc_channel.h"
+#include "skia/ext/image_operations.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/zlib/google/zip.h"
 #include "ui/gfx/codec/jpeg_codec.h"
 #include "ui/gfx/size.h"
 
 #if !defined(OS_ANDROID)
 #include "chrome/utility/profile_import_handler.h"
 #endif
 
 #if defined(OS_WIN)
@@ skipping 32 matching lines @@
     const extensions::api::media_galleries::MediaMetadata& metadata,
     const std::vector<metadata::AttachedImage>& attached_images) {
   Send(new ChromeUtilityHostMsg_ParseMediaMetadata_Finished(
       true, *metadata.ToValue(), attached_images));
   ReleaseProcessIfNeeded();
 }
 #endif
 
 }  // namespace
 
+int64_t ChromeContentUtilityClient::max_ipc_message_size_ =
+    IPC::Channel::kMaximumMessageSize;
+
 ChromeContentUtilityClient::ChromeContentUtilityClient()
     : filter_messages_(false) {
 #if !defined(OS_ANDROID)
   handlers_.push_back(new ProfileImportHandler());
 #endif
 
 #if defined(ENABLE_EXTENSIONS)
   handlers_.push_back(new extensions::ExtensionsHandler());
   handlers_.push_back(new image_writer::ImageWriterHandler());
 #endif
@@ skipping 83 matching lines @@
 
 #if defined(ENABLE_MDNS)
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kUtilityProcessEnableMDns)) {
     local_discovery::ServiceDiscoveryMessageHandler::PreSandboxStartup();
   }
 #endif  // ENABLE_MDNS
 }
 
 // static
-void ChromeContentUtilityClient::DecodeImage(
-    const std::vector<unsigned char>& encoded_data) {
-  const SkBitmap& decoded_image = content::DecodeImage(&encoded_data[0],
-                                                       gfx::Size(),
-                                                       encoded_data.size());
+SkBitmap ChromeContentUtilityClient::DecodeImage(
+    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit) {
+  SkBitmap decoded_image = content::DecodeImage(&encoded_data[0],
+                                                gfx::Size(),
+                                                encoded_data.size());
+
+  int64_t struct_size = sizeof(ChromeUtilityHostMsg_DecodeImage_Succeeded);
+  int64_t image_size = decoded_image.computeSize64();
+  int halves = 0;
+  while (struct_size + (image_size >> 2*halves) > max_ipc_message_size_)
+    halves++;
+  if (halves) {
+    if (shrink_to_fit) {
+      // If decoded image is too large for IPC message, shrink it by halves.
+      // This prevents quality loss, and should never overshrink on displays
+      // smaller than 3600x2400.
+      // TODO (Issue 416916): Instead of shrinking, return via shared memory
+      decoded_image = skia::ImageOperations::Resize(
+          decoded_image, skia::ImageOperations::RESIZE_LANCZOS3,
+          decoded_image.width() >> halves, decoded_image.height() >> halves);
+    } else {
+      // Image too big for IPC message, but caller didn't request resize;
+      // pre-delete image so DecodeImageAndSend() will send an error.
+      decoded_image.reset();
+      LOG(ERROR) << "Decoded image too large for IPC message";
+    }
+  }
+
+  return decoded_image;
+}
+
+// static
+void ChromeContentUtilityClient::DecodeImageAndSend(
+    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit){
+  SkBitmap decoded_image = DecodeImage(encoded_data, shrink_to_fit);
+
   if (decoded_image.empty()) {
     Send(new ChromeUtilityHostMsg_DecodeImage_Failed());
   } else {
     Send(new ChromeUtilityHostMsg_DecodeImage_Succeeded(decoded_image));
   }
   ReleaseProcessIfNeeded();
 }
 
 void ChromeContentUtilityClient::OnUnpackWebResource(
     const std::string& resource_data) {
   // Parse json data.
   // TODO(mrc): Add the possibility of a template that controls parsing, and
   // the ability to download and verify images.
   WebResourceUnpacker unpacker(resource_data);
   if (unpacker.Run()) {
     Send(new ChromeUtilityHostMsg_UnpackWebResource_Succeeded(
         *unpacker.parsed_json()));
   } else {
     Send(new ChromeUtilityHostMsg_UnpackWebResource_Failed(
         unpacker.error_message()));
   }
 
   ReleaseProcessIfNeeded();
 }
 
 void ChromeContentUtilityClient::OnDecodeImage(
-    const std::vector<unsigned char>& encoded_data) {
-  DecodeImage(encoded_data);
+    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit) {
+  DecodeImageAndSend(encoded_data, shrink_to_fit);
 }
 
 #if defined(OS_CHROMEOS)
 void ChromeContentUtilityClient::OnCreateZipFile(
     const base::FilePath& src_dir,
     const std::vector<base::FilePath>& src_relative_paths,
     const base::FileDescriptor& dest_fd) {
   bool succeeded = true;
 
   // Check sanity of source relative paths. Reject if path is absolute or
@@ skipping 91 matching lines @@
     const std::string& mime_type, int64 total_size, bool get_attached_images) {
   // Only one IPCDataSource may be created and added to the list of handlers.
   metadata::IPCDataSource* source = new metadata::IPCDataSource(total_size);
   handlers_.push_back(source);
 
   metadata::MediaMetadataParser* parser = new metadata::MediaMetadataParser(
       source, mime_type, get_attached_images);
   parser->Start(base::Bind(&FinishParseMediaMetadata, base::Owned(parser)));
 }
 #endif