ppapi/api/trusted/ppb_file_io_trusted.idl

/* Copyright (c) 2012 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.
 */

/*
 * This file defines the trusted file IO interface
 */

label Chrome {
  M14= 0.4
};

// Available only to trusted implementations.
interface PPB_FileIOTrusted {
  /**
   * Returns a file descriptor corresponding to the given FileIO object. On
   * Windows, returns a HANDLE; on all other platforms, returns a POSIX file
   * descriptor. The FileIO object must have been opened with a successful
   * call to FileIO::Open.  The file descriptor will be closed automatically
   * when the FileIO object is closed or destroyed.
   *
   * TODO(hamaji): Remove this and use RequestOSFileHandle instead.
   */
  int32_t GetOSFileDescriptor([in] PP_Resource file_io);

  /**
   * Notifies the browser that underlying file will be modified.  This gives
   * the browser the opportunity to apply quota restrictions and possibly
   * return an error to indicate that the write is not allowed.
   */
  int32_t WillWrite([in] PP_Resource file_io,
                    [in] int64_t offset,
                    [in] int32_t bytes_to_write,
                    [in] PP_CompletionCallback callback);

  /**
   * Notifies the browser that underlying file will be modified.  This gives
   * the browser the opportunity to apply quota restrictions and possibly
   * return an error to indicate that the write is not allowed.
   *
   * TODO(darin): Maybe unify the above into a single WillChangeFileSize
   * method?  The above methods have the advantage of mapping to PPB_FileIO
   * Write and SetLength calls.  WillChangeFileSize would require the caller to
   * compute the file size resulting from a Write call, which may be
   * undesirable.
   */
  int32_t WillSetLength([in] PP_Resource file_io,
                        [in] int64_t length,
                        [in] PP_CompletionCallback callback);

};