storage/browser/blob/blob_data_handle.cc

   1 // Copyright (c) 2013 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 #include "storage/browser/blob/blob_data_handle.h"
   6
   7 #include "base/bind.h"
   8 #include "base/location.h"
   9 #include "base/logging.h"
  10 #include "base/sequenced_task_runner.h"
  11 #include "storage/browser/blob/blob_data_snapshot.h"
  12 #include "storage/browser/blob/blob_storage_context.h"
  13
  14 namespace storage {
  15
  16 BlobDataHandle::BlobDataHandleShared::BlobDataHandleShared(
  17     const std::string& uuid,
  18     BlobStorageContext* context,
  19     base::SequencedTaskRunner* task_runner)
  20     : uuid_(uuid), context_(context->AsWeakPtr()) {
  21   context_->IncrementBlobRefCount(uuid);
  22 }
  23
  24 scoped_ptr<BlobDataSnapshot>
  25 BlobDataHandle::BlobDataHandleShared::CreateSnapshot() const {
  26   return context_->CreateSnapshot(uuid_).Pass();
  27 }
  28
  29 const std::string& BlobDataHandle::BlobDataHandleShared::uuid() const {
  30   return uuid_;
  31 }
  32
  33 BlobDataHandle::BlobDataHandleShared::~BlobDataHandleShared() {
  34   if (context_.get())
  35     context_->DecrementBlobRefCount(uuid_);
  36 }
  37
  38 BlobDataHandle::BlobDataHandle(const std::string& uuid,
  39                                BlobStorageContext* context,
  40                                base::SequencedTaskRunner* task_runner)
  41     : io_task_runner_(task_runner),
  42       shared_(new BlobDataHandleShared(uuid, context, task_runner)) {
  43   DCHECK(io_task_runner_.get());
  44   DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
  45 }
  46
  47 BlobDataHandle::BlobDataHandle(const BlobDataHandle& other) {
  48   io_task_runner_ = other.io_task_runner_;
  49   shared_ = other.shared_;
  50 }
  51
  52 BlobDataHandle::~BlobDataHandle() {
  53   BlobDataHandleShared* raw = shared_.get();
  54   raw->AddRef();
  55   shared_ = nullptr;
  56   io_task_runner_->ReleaseSoon(FROM_HERE, raw);
  57 }
  58
  59 scoped_ptr<BlobDataSnapshot> BlobDataHandle::CreateSnapshot() const {
  60   DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
  61   return shared_->CreateSnapshot().Pass();
  62 }
  63
  64 const std::string& BlobDataHandle::uuid() const {
  65   return shared_->uuid();
  66 }
  67
  68 }  // namespace storage