CRX FileSystem Pepper private API

ppapi/host/file_system_registry.h

+// 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.
+
+#ifndef PPAPI_HOST_FILE_SYSTEM_REGISTRY_H_
+#define PPAPI_HOST_FILE_SYSTEM_REGISTRY_H_
+
+#include <map>
+#include <string>
+#include <utility>
+
+#include "base/basictypes.h"
+#include "base/memory/singleton.h"
+#include "ppapi/c/pp_file_info.h"
+#include "ppapi/c/pp_instance.h"
+#include "ppapi/c/pp_resource.h"
+#include "ppapi/host/ppapi_host_export.h"
+
+class GURL;
+
+namespace ppapi {
+namespace host {
+
+// A singleton class to manage file system registry.  The main purpose of this
+// class is to allow a host to peek information of a registered file system,
+// which can be a PPB_FileSystem or PPB_Ext_CrxFileSystem_Private.
+class PPAPI_HOST_EXPORT FileSystemRegistry {

[yzshen1, 2013/04/30 19:31:19]

I think we don't need to have yet another map.
We could have a common base class FileSystemHostBase for PepperFileSystemHost
and PepperExtCrxFileSystemRendererHost. And then we can cast a ResourceHost to
FileSystemHostBase, right?

[victorhsieh, 2013/04/30 22:04:32]

Do you mean to add a ...
FileSystemHostBase* ResourceHost::GetFileSystemHostBase(PP_Resource); ?  Simply
cast a ResourceHost to FileSystemHostBase sounds error prune to me.

[yzshen1, 2013/05/01 17:45:10]

I agree. :/ This is another reason I think we should not add a different kind of
file system PP_Resource.

+ public:
+  class FileSystemPeeker {
+   public:
+    virtual PP_FileSystemType GetType() const = 0;
+    virtual bool IsOpened() const = 0;
+    virtual const GURL& GetRootUrl() const = 0;
+  };
+
+  static FileSystemRegistry* GetInstance();
+
+  void Register(PP_Instance instance,
+                PP_Resource resource,
+                const FileSystemPeeker* peeker);
+
+  void Unregister(PP_Instance instance, PP_Resource resource);
+
+  const FileSystemPeeker& LookUp(PP_Instance instance,
+                                 PP_Resource resource) const;
+
+ private:
+  FileSystemRegistry();
+  ~FileSystemRegistry();
+  friend struct DefaultSingletonTraits<FileSystemRegistry>;
+
+  typedef std::map<std::pair<PP_Instance, PP_Resource>,
+                   const FileSystemPeeker*> ResourceMap;
+  ResourceMap mapping_;
+
+  DISALLOW_COPY_AND_ASSIGN(FileSystemRegistry);
+};
+
+}  // namespace host
+}  // namespace ppapi
+
+#endif // PPAPI_HOST_FILE_SYSTEM_REGISTRY_H_