Index: chrome/browser/image_decoder.h |
diff --git a/chrome/browser/image_decoder.h b/chrome/browser/image_decoder.h |
index 2206dd9f454ebcbfc3a29674cf41e1d42eb594ee..d4615cff82d437137f86b53da416defe804eb55f 100644 |
--- a/chrome/browser/image_decoder.h |
+++ b/chrome/browser/image_decoder.h |
@@ -5,33 +5,55 @@ |
#ifndef CHROME_BROWSER_IMAGE_DECODER_H_ |
#define CHROME_BROWSER_IMAGE_DECODER_H_ |
+#include <map> |
#include <string> |
#include <vector> |
#include "base/compiler_specific.h" |
+#include "base/lazy_instance.h" |
#include "base/memory/ref_counted.h" |
+#include "base/synchronization/lock.h" |
#include "base/threading/sequenced_worker_pool.h" |
+#include "base/timer/timer.h" |
+#include "content/public/browser/utility_process_host.h" |
#include "content/public/browser/utility_process_host_client.h" |
class SkBitmap; |
-// Decodes an image in a sandboxed process. |
+// This is a helper class for decoding images safely in a utility process. To |
+// use this, call ImageDecoder::Start(...) or |
+// ImageDecoder::StartWithOptions(...) on any thread. |
+// |
+// Internally, most of the work happens on the IO thread, and then |
+// the callback (ImageRequest::OnImageDecoded or |
+// ImageRequest::OnDecodeImageFailed) is posted back to the |task_runner_| |
+// associated with the ImageRequest. |
+// The Cancel() method runs on whichever thread called it. |map_lock_| is used |
+// to protect the data that is accessed from multiple threads. |
class ImageDecoder : public content::UtilityProcessHostClient { |
public: |
- class Delegate { |
+ class ImageRequest { |
public: |
// Called when image is decoded. |
- // |decoder| is used to identify the image in case of decoding several |
- // images simultaneously. |
- virtual void OnImageDecoded(const ImageDecoder* decoder, |
- const SkBitmap& decoded_image) = 0; |
+ virtual void OnImageDecoded(const SkBitmap& decoded_image) = 0; |
- // Called when decoding image failed. Delegate can do some cleanup in |
+ // Called when decoding image failed. ImageRequest can do some cleanup in |
// this handler. |
- virtual void OnDecodeImageFailed(const ImageDecoder* decoder) {} |
+ virtual void OnDecodeImageFailed() {} |
+ |
+ base::SequencedTaskRunner* task_runner() const { |
+ return task_runner_.get(); |
+ } |
protected: |
- virtual ~Delegate() {} |
+ explicit ImageRequest( |
+ const scoped_refptr<base::SequencedTaskRunner>& task_runner); |
+ virtual ~ImageRequest(); |
+ |
+ private: |
+ // The thread to post OnImageDecoded or OnDecodeImageFailed once the |
+ // the image has been decoded. |
+ const scoped_refptr<base::SequencedTaskRunner> task_runner_; |
}; |
enum ImageCodec { |
@@ -39,44 +61,71 @@ class ImageDecoder : public content::UtilityProcessHostClient { |
ROBUST_JPEG_CODEC, // Restrict decoding to robust jpeg codec. |
}; |
- ImageDecoder(Delegate* delegate, |
- const std::string& image_data, |
- ImageCodec image_codec); |
- |
- ImageDecoder(Delegate* delegate, |
- const std::vector<char>& image_data, |
- ImageCodec image_codec); |
+ // Calls StartWithOptions with ImageCodec::DEFAULT_CODEC and |
+ // shrink_to_fit = false. |
+ static void Start(ImageRequest* image_request, |
+ const std::string& image_data); |
// Starts asynchronous image decoding. Once finished, the callback will be |
- // posted back to |task_runner|. |
- void Start(scoped_refptr<base::SequencedTaskRunner> task_runner); |
+ // posted back to image_request's |task_runner_|. |
+ static void StartWithOptions(ImageRequest* image_request, |
+ const std::string& image_data, |
+ ImageCodec image_codec, |
+ bool shrink_to_fit); |
- const std::vector<unsigned char>& get_image_data() const { |
- return image_data_; |
- } |
- |
- void set_delegate(Delegate* delegate) { delegate_ = delegate; } |
- void set_shrink_to_fit(bool shrink_to_fit) { shrink_to_fit_ = shrink_to_fit; } |
+ // Removes all instances of image_request from |image_request_id_map_|, |
+ // ensuring callbacks are not made to the image_request after it is destroyed. |
+ static void Cancel(ImageRequest* image_request); |
private: |
+ friend struct base::DefaultLazyInstanceTraits<ImageDecoder>; |
+ |
+ ImageDecoder(); |
// It's a reference counted object, so destructor is private. |
~ImageDecoder() override; |
- // Overidden from UtilityProcessHostClient: |
+ // Sends a request to the sandboxed process to decode the image. Starts |
+ // batch mode if necessary. |
+ void DecodeImageInSandbox(ImageRequest* image_request, |
+ const std::vector<unsigned char>& image_data, |
+ ImageCodec image_codec, |
+ bool shrink_to_fit); |
+ |
+ void CancelImpl(ImageRequest* image_request); |
+ |
+ using RequestMap = std::map<int, ImageRequest*>; |
+ |
+ // Starts UtilityProcessHost in batch mode and starts |batch_mode_timer_|. |
+ void StartBatchMode(); |
+ |
+ // Stops batch mode if no requests have come in since |
+ // kBatchModeTimeoutSeconds. |
+ void StopBatchMode(); |
+ |
+ // Overidden from UtilityProcessHostClient. |
bool OnMessageReceived(const IPC::Message& message) override; |
// IPC message handlers. |
- void OnDecodeImageSucceeded(const SkBitmap& decoded_image); |
- void OnDecodeImageFailed(); |
+ void OnDecodeImageSucceeded(const SkBitmap& decoded_image, int request_id); |
+ void OnDecodeImageFailed(int request_id); |
+ |
+ // id to use for the next Start request that comes in. |
+ int image_request_id_counter_; |
+ |
+ // Map of request id's to ImageRequests. |
+ RequestMap image_request_id_map_; |
+ |
+ // Protects |image_request_id_map_| and |image_request_id_counter_|. |
+ base::Lock map_lock_; |
+ |
+ // The UtilityProcessHost requests are sent to. |
+ base::WeakPtr<content::UtilityProcessHost> utility_process_host_; |
- // Launches sandboxed process that will decode the image. |
- void DecodeImageInSandbox(const std::vector<unsigned char>& image_data); |
+ // Calls StopBatchMode after kBatchModeTimeoutSeconds have elapsed. |
+ base::RepeatingTimer<ImageDecoder> batch_mode_timer_; |
- Delegate* delegate_; |
- std::vector<unsigned char> image_data_; |
- const ImageCodec image_codec_; |
- scoped_refptr<base::SequencedTaskRunner> task_runner_; |
- bool shrink_to_fit_; // if needed for IPC msg size limit |
+ // The time Start was last called. |
+ base::TimeTicks last_request_; |
DISALLOW_COPY_AND_ASSIGN(ImageDecoder); |
}; |