New blobstoragecontext for use in the main browser process, not plugged in yet.

webkit/blob/blob_data_handle.cc

+// 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.
+
+#include "webkit/blob/blob_data_handle.h"
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/sequenced_task_runner.h"
+#include "webkit/blob/blob_data.h"
+#include "webkit/blob/blob_storage_context.h"
+
+namespace webkit_blob {
+
+BlobDataHandle::BlobDataHandle(BlobData* blob_data, BlobStorageContext* context,
+                               base::SequencedTaskRunner* task_runner)
+    : blob_data_(blob_data),
+      context_(context->AsWeakPtr()),
+      io_task_runner_(task_runner) {
+  // Ensures the uuid remains registered and the underlying data is not deleted.
+  DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
+  context_->IncrementBlobRefCount(blob_data->uuid());
+  blob_data_->AddRef();
+}
+
+BlobDataHandle::~BlobDataHandle() {
+  if (io_task_runner_->RunsTasksOnCurrentThread()) {
+    // Note: Do not test context_ or alter the blob_data_ refcount
+    // on the wrong thread.
+    if (context_.get())
+      context_->DecrementBlobRefCount(blob_data_->uuid());
+    blob_data_->Release();
+    return;
+  }
+
+  io_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&DeleteHelper, context_, base::Unretained(blob_data_)));
+}
+
+BlobData* BlobDataHandle::data() const {
+  DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
+  return blob_data_;
+}
+
+// static
+void BlobDataHandle::DeleteHelper(
+    base::WeakPtr<BlobStorageContext> context,
+    BlobData* blob_data) {
+  if (context.get())
+    context->DecrementBlobRefCount(blob_data->uuid());
+  blob_data->Release();
+}
+
+}  // namespace webkit_blob