Blobs: Mechanism for creating Blobs in browser process, then transferring to renderer.

content/browser/fileapi/chrome_blob_storage_context.h

 // 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.
 
 #ifndef CONTENT_BROWSER_FILEAPI_CHROME_BLOB_STORAGE_CONTEXT_H_
 #define CONTENT_BROWSER_FILEAPI_CHROME_BLOB_STORAGE_CONTEXT_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/fileapi/blob_context.h"
 
 namespace webkit_blob {
 class BlobStorageContext;
 }
 
 namespace content {
 class BrowserContext;
 struct ChromeBlobStorageContextDeleter;
 
 // A context class that keeps track of BlobStorageController used by the chrome.
 // There is an instance associated with each BrowserContext. There could be
 // multiple URLRequestContexts in the same browser context that refers to the
 // same instance.
 //
 // All methods, except the ctor, are expected to be called on
 // the IO thread (unless specifically called out in doc comments).
 class CONTENT_EXPORT ChromeBlobStorageContext
-    : public base::RefCountedThreadSafe<ChromeBlobStorageContext,
+    : public BlobContext,
+      public base::RefCountedThreadSafe<ChromeBlobStorageContext,
                                         ChromeBlobStorageContextDeleter> {
  public:
   ChromeBlobStorageContext();
 
   static ChromeBlobStorageContext* GetFor(
       BrowserContext* browser_context);
 
   void InitializeOnIOThread();
 
   webkit_blob::BlobStorageContext* context() const {
     return context_.get();
   }
 
+  // BlobContext implementation.
+  virtual void CreateMemoryBackedBlob(
+      const char* data, size_t length, const BlobCallback& callback) OVERRIDE;
+
  protected:
   virtual ~ChromeBlobStorageContext();
 
  private:
   friend class base::DeleteHelper<ChromeBlobStorageContext>;
   friend class base::RefCountedThreadSafe<ChromeBlobStorageContext,
                                           ChromeBlobStorageContextDeleter>;
   friend struct ChromeBlobStorageContextDeleter;
 
+  scoped_ptr<webkit_blob::BlobDataHandle> CreateMemoryBackedBlobOnIOThread(
+      const char* data, size_t length, const BlobCallback& callback);
+
   void DeleteOnCorrectThread() const;
 
   scoped_ptr<webkit_blob::BlobStorageContext> context_;
 };
 
 struct ChromeBlobStorageContextDeleter {
   static void Destruct(const ChromeBlobStorageContext* context) {
     context->DeleteOnCorrectThread();
   }
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FILEAPI_CHROME_BLOB_STORAGE_CONTEXT_H_