Blobs: Catching browser-process created Blobs in extension code.

chrome/browser/extensions/blob_holder.cc

+// Copyright 2014 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 "chrome/browser/extensions/blob_holder.h"
+
+#include "base/logging.h"
+#include "content/public/browser/blob_handle.h"
+#include "content/public/browser/render_process_host.h"
+#include "extensions/common/extension_messages.h"
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(extensions::BlobHolder);
+
+namespace extensions {
+
+BlobHolder::~BlobHolder() {}
+
+void BlobHolder::HoldBlobReference(scoped_ptr<content::BlobHandle> blob) {
+  DCHECK(!ContainsBlobHandle(blob.get()));
+  held_blobs_.push_back(blob.release());
+}
+
+BlobHolder::BlobHolder(content::WebContents* web_contents)
+    : content::WebContentsObserver(web_contents) {
+}
+
+bool BlobHolder::ContainsBlobHandle(content::BlobHandle* handle) const {
+  for (BlobHandleVector::const_iterator it = held_blobs_.begin();
+       it != held_blobs_.end(); ++it) {
+    if (*it == handle)
+      return true;
+  }
+
+  return false;
+}
+
+bool BlobHolder::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(BlobHolder, message)
+    IPC_MESSAGE_HANDLER(ExtensionHostMsg_TransferBlobsAck, OnTransferBlobsAck)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void BlobHolder::OnTransferBlobsAck(
+    const std::vector<std::string>& blob_uuids) {
+  for (std::vector<std::string>::const_iterator uuid_it = blob_uuids.begin();
+       uuid_it != blob_uuids.end(); ++uuid_it) {
+    bool found = false;
+    for (BlobHandleVector::iterator blob_handle_it = held_blobs_.begin();
+         blob_handle_it != held_blobs_.end(); ++blob_handle_it) {
+      if ((*blob_handle_it)->GetUUID() == *uuid_it) {
+        held_blobs_.erase(blob_handle_it);
+        found = true;
+        break;
+      }
+    }
+
+    if (!found) {
+      DLOG(ERROR) << "Tried to release a Blob we don't have ownership to."
+          << "UUID: " << *uuid_it;
+      web_contents()->GetRenderProcessHost()->ReceivedBadMessage();
+    }
+  }
+}
+
+}  // namespace extensions