[Blob] Blob paging to disk patch.

storage/browser/blob/blob_storage_context.h

 // Copyright (c) 2013 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.
 
 #ifndef STORAGE_BROWSER_BLOB_BLOB_STORAGE_CONTEXT_H_
 #define STORAGE_BROWSER_BLOB_BLOB_STORAGE_CONTEXT_H_
 
+#include <list>
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
+#include "base/containers/mru_cache.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "storage/browser/blob/blob_data_handle.h"
+#include "storage/browser/blob/blob_memory_controller.h"
 #include "storage/browser/blob/blob_storage_registry.h"
 #include "storage/browser/blob/internal_blob_data.h"
 #include "storage/browser/storage_browser_export.h"
 #include "storage/common/blob_storage/blob_storage_constants.h"
 #include "storage/common/data_element.h"
 
 class GURL;
 
 namespace base {
 class FilePath;
 class Time;
 }
 
 namespace content {
 class BlobStorageContextTest;
 class BlobStorageHost;
 }
 
 namespace storage {
 
 class BlobDataBuilder;
 class BlobDataItem;
 class BlobDataSnapshot;
+class BlobMemoryController;
 class ShareableBlobDataItem;
 
 // This class handles the logistics of blob Storage within the browser process,
 // and maintains a mapping from blob uuid to the data. The class is single
 // threaded and should only be used on the IO thread.
 // In chromium, there is one instance per profile.
 class STORAGE_EXPORT BlobStorageContext
     : public base::SupportsWeakPtr<BlobStorageContext> {
  public:
   BlobStorageContext();
+  BlobStorageContext(bool enable_disk,
+                     const base::FilePath& blob_storage_dir,
+                     scoped_refptr<base::TaskRunner> file_runner);
   ~BlobStorageContext();
 
   scoped_ptr<BlobDataHandle> GetBlobDataFromUUID(const std::string& uuid);
   scoped_ptr<BlobDataHandle> GetBlobDataFromPublicURL(const GURL& url);
 
   // Useful for coining blobs from within the browser process. If the
   // blob cannot be added due to memory consumption, returns NULL.
   // A builder should not be used twice to create blobs, as the internal
   // resources are refcounted instead of copied for memory efficiency.
   // To cleanly use a builder multiple times, please call Clone() on the
   // builder, or even better for memory savings, clear the builder and append
   // the previously constructed blob.
   scoped_ptr<BlobDataHandle> AddFinishedBlob(const BlobDataBuilder& builder);
 
   // Deprecated, use const ref version above.
   scoped_ptr<BlobDataHandle> AddFinishedBlob(const BlobDataBuilder* builder);
 
   // Useful for coining blob urls from within the browser process.
   bool RegisterPublicBlobURL(const GURL& url, const std::string& uuid);
   void RevokePublicBlobURL(const GURL& url);
 
   size_t memory_usage() const { return memory_usage_; }
   size_t memory_available() const {
     return kBlobStorageMaxMemoryUsage - memory_usage_;
   }
 
   const BlobStorageRegistry& registry() { return registry_; }
 
- private:
-  typedef BlobStorageRegistry::Entry BlobRegistryEntry;
-  friend class content::BlobStorageHost;
-  friend class content::BlobStorageContextTest;
+ protected:
+  friend class BlobAsyncBuilderHost;
   friend class BlobDataHandle::BlobDataHandleShared;
-  friend class ViewBlobInternalsJob;
 
   void BuildAndStoreBlob(const BlobDataBuilder& external_builder);
 
   // #### Called by BlobDataHandle ####
   scoped_ptr<BlobDataSnapshot> CreateSnapshot(const std::string& uuid);
   bool IsBlobConstructing(const std::string& uuid) const;
   // Returns if construction was successful.
   void RunOnConstructionComplete(const std::string& uuid,
                                  const base::Callback<void(bool)>& done);
   // ##################################
 
+ private:
+  typedef BlobStorageRegistry::Entry BlobRegistryEntry;
+
+  friend class content::BlobStorageHost;
+  friend class content::BlobStorageContextTest;
+  friend class ViewBlobInternalsJob;
+
+  void BuildAndStoreBlob(BlobDataBuilder* external_builder);
+
   // ### Methods called by BlobStorageHost ###
   void RegisterBlobUUID(const std::string& uuid);
   bool MaybeStartAsyncBlobTransfer(const std::string& uuid);
   void FinishAsyncBlobTransfer(
       base::Closure done,
       base::Callback<void(storage::IPCBlobCreationCancelCode)> cancel,
       const storage::BlobDataBuilder& builder);
   void CancelAsyncBlobTransfer(
       const std::string& uuid,
       base::Callback<void(storage::IPCBlobCreationCancelCode)> cancel,
@@ skipping 21 matching lines @@
 
   // Deconstructs the blob and appends it's contents to the target blob.  Items
   // are shared if possible, and copied if the given offset and length
   // have to split an item.
   bool AppendBlob(const std::string& target_blob_uuid,
                   const InternalBlobData& blob,
                   uint64_t offset,
                   uint64_t length,
                   InternalBlobData::Builder* target_blob_data);
 
+  uint64_t GetAndIncrementItemId();
+  void UpdateItemsInRecents(BlobRegistryEntry* entry);
+
   BlobStorageRegistry registry_;
+  BlobMemoryController memory_controller_;
+  uint64_t next_item_id_ = 0;
 
   // Used to keep track of how much memory is being utilized for blob data,
   // we count only the items of TYPE_DATA which are held in memory and not
   // items of TYPE_FILE.
-  size_t memory_usage_;
+  size_t memory_usage_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(BlobStorageContext);
 };
 
 }  // namespace storage
 
 #endif  // STORAGE_BROWSER_BLOB_BLOB_STORAGE_CONTEXT_H_