content/browser/fileapi/blob_storage_host.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_FILEAPI_STORAGE_HOST_H_
   6 #define CONTENT_BROWSER_FILEAPI_STORAGE_HOST_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <string>
  11
  12 #include "base/compiler_specific.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "content/common/content_export.h"
  15 #include "webkit/common/blob/blob_data.h"
  16
  17 class GURL;
  18
  19 namespace storage {
  20 class BlobDataHandle;
  21 class BlobStorageHost;
  22 class BlobStorageContext;
  23 }
  24
  25 using storage::BlobStorageContext;
  26 using storage::BlobData;
  27
  28 namespace content {
  29
  30 // This class handles the logistics of blob storage for a single child process.
  31 // There is one instance per child process. When the child process
  32 // terminates all blob references attibutable to that process go away upon
  33 // destruction of the instance. The class is single threaded and should
  34 // only be used on the IO thread.
  35 class CONTENT_EXPORT BlobStorageHost {
  36  public:
  37   explicit BlobStorageHost(BlobStorageContext* context);
  38   ~BlobStorageHost();
  39
  40   // Methods to support the IPC message protocol.
  41   // A false return indicates a problem with the inputs
  42   // like a non-existent or pre-existent uuid or url.
  43   bool StartBuildingBlob(const std::string& uuid) WARN_UNUSED_RESULT;
  44   bool AppendBlobDataItem(const std::string& uuid,
  45                           const BlobData::Item& data_item) WARN_UNUSED_RESULT;
  46   bool CancelBuildingBlob(const std::string& uuid) WARN_UNUSED_RESULT;
  47   bool FinishBuildingBlob(const std::string& uuid,
  48                           const std::string& type) WARN_UNUSED_RESULT;
  49   bool IncrementBlobRefCount(const std::string& uuid) WARN_UNUSED_RESULT;
  50   bool DecrementBlobRefCount(const std::string& uuid) WARN_UNUSED_RESULT;
  51   bool RegisterPublicBlobURL(const GURL& blob_url,
  52                              const std::string& uuid) WARN_UNUSED_RESULT;
  53   bool RevokePublicBlobURL(const GURL& blob_url) WARN_UNUSED_RESULT;
  54
  55  private:
  56   typedef std::map<std::string, int> BlobReferenceMap;
  57
  58   bool IsInUseInHost(const std::string& uuid);
  59   bool IsBeingBuiltInHost(const std::string& uuid);
  60   bool IsUrlRegisteredInHost(const GURL& blob_url);
  61
  62   // Collection of blob ids and a count of how many usages
  63   // of that id are attributable to this consumer.
  64   BlobReferenceMap blobs_inuse_map_;
  65
  66   // The set of public blob urls coined by this consumer.
  67   std::set<GURL> public_blob_urls_;
  68
  69   base::WeakPtr<BlobStorageContext> context_;
  70
  71   DISALLOW_COPY_AND_ASSIGN(BlobStorageHost);
  72 };
  73
  74 }  // namespace content
  75
  76 #endif  // CONTENT_BROWSER_FILEAPI_STORAGE_HOST_H_