components/filesystem/util.h

// Copyright 2015 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 COMPONENTS_FILESYSTEM_UTIL_H_
#define COMPONENTS_FILESYSTEM_UTIL_H_

#include <stdint.h>

#include "base/files/file.h"
#include "components/filesystem/public/interfaces/types.mojom.h"

namespace mojo {
class String;
}

namespace filesystem {

// Validation functions (typically used to check arguments; they return
// |ERROR_OK| if valid, else the standard/recommended error for the validation
// error):

// Checks if |path|, which must be non-null, is (looks like) a valid (relative)
// path. (On failure, returns |ERROR_INVALID_ARGUMENT| if |path| is not UTF-8,
// or |ERROR_PERMISSION_DENIED| if it is not relative.)
FileError IsPathValid(const mojo::String& path);

// Checks if |whence| is a valid (known) |Whence| value. (On failure, returns
// |ERROR_UNIMPLEMENTED|.)
FileError IsWhenceValid(Whence whence);

// Checks if |offset| is a valid file offset (from some point); this is
// implementation-dependent (typically checking if |offset| fits in an |off_t|).
// (On failure, returns |ERROR_OUT_OF_RANGE|.)
FileError IsOffsetValid(int64_t offset);

// Conversion functions:

// Returns the platform dependent error details converted to the
// filesystem.Error enum.
FileError GetError(const base::File& file);

// Serializes Info to the wire format.
FileInformationPtr MakeFileInformation(const base::File::Info& info);

// Creates an absolute file path and ensures that we don't try to traverse up.
FileError ValidatePath(const mojo::String& raw_path,
                       const base::FilePath& filesystem_base,
                       base::FilePath* out);

}  // namespace filesystem

#endif  // COMPONENTS_FILESYSTEM_UTIL_H_