base/file_util_proxy.h

// Copyright (c) 2010 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 BASE_FILE_SYSTEM_PROXY_H_
#define BASE_FILE_SYSTEM_PROXY_H_

#include "base/callback.h"
#include "base/platform_file.h"
#include "base/ref_counted.h"
#include "base/tracked_objects.h"

namespace file_util {
struct FileInfo;
}

namespace base {

class MessageLoopProxy;

// This class provides asynchronous access to common file routines.
class FileUtilProxy {
 public:
  // This callback is used by methods that report only an error code.  It is
  // valid to pass NULL as the callback parameter to any function that takes a
  // StatusCallback, in which case the operation will complete silently.
  typedef Callback1<int /* error code */>::Type StatusCallback;

  // Creates or opens a file with the given flags.  It is invalid to pass NULL
  // for the callback.
  typedef Callback3<int /* error code */, base::PassPlatformFile,
                    bool /* created */>::Type CreateOrOpenCallback;
  static bool CreateOrOpen(scoped_refptr<MessageLoopProxy> message_loop_proxy,
                           const FilePath& file_path,
                           int file_flags,
                           CreateOrOpenCallback* callback);

  // Creates a temporary file for writing.  The path and an open file handle
  // are returned.  It is invalid to pass NULL for the callback.
  typedef Callback3<int /* error code */, base::PassPlatformFile,
                    FilePath>::Type CreateTemporaryCallback;
  static bool CreateTemporary(
      scoped_refptr<MessageLoopProxy> message_loop_proxy,
      CreateTemporaryCallback* callback);

  // Close the given file handle.
  static bool Close(scoped_refptr<MessageLoopProxy> message_loop_proxy,
                    base::PlatformFile,
                    StatusCallback* callback);

  // Deletes a file or empty directory.
  static bool Delete(scoped_refptr<MessageLoopProxy> message_loop_proxy,
                     const FilePath& file_path,
                     StatusCallback* callback);

  // Deletes a directory and all of its contents.
  static bool RecursiveDelete(
      scoped_refptr<MessageLoopProxy> message_loop_proxy,
      const FilePath& file_path,
      StatusCallback* callback);

  // Retrieves the information about a file. It is invalid to pass NULL for the
  // callback.
  typedef Callback2<bool /*exists*/,
                    const file_util::FileInfo& /*file_info*/
                    >::Type GetFileInfoCallback;
  static bool GetFileInfo(
      scoped_refptr<MessageLoopProxy> message_loop_proxy,
      const FilePath& file_path,
      GetFileInfoCallback* callback);

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(FileUtilProxy);
};

} // namespace base

#endif  // BASE_FILE_SYSTEM_PROXY_H_