iox-eclipse-iceoryx#1036 Add C++17 filesystem perms feature

Signed-off-by: Christian Eltzschig <me@elchris.org>

iceoryx_hoofs/include/iceoryx_hoofs/cxx/filesystem.hpp

@@ -0,0 +1,74 @@
+// Copyright (c) 2022 by Apex.AI Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// SPDX-License-Identifier: Apache-2.0
+#ifndef IOX_HOOFS_CXX_FILESYSTEM_HPP
+#define IOX_HOOFS_CXX_FILESYSTEM_HPP
+
+namespace iox
+{
+namespace cxx
+{
+/// @brief this enum class implements the filesystem perms feature of C++17. The
+///        API is identical to the C++17 one so that the class can be removed
+///        as soon as iceoryx switches to C++17.
+enum class perms
+{
+    /// @brief Deny everything
+    none = 0,
+
+    /// @brief owner has read permission
+    owner_read = 0400,
+    /// @brief owner has write permission
+    owner_write = 0200,
+    /// @brief owner has execution permission
+    owner_exec = 0100,
+    /// @brief owner has all permissions
+    owner_all = 0700,
+
+    /// @brief group has read permission
+    group_read = 040,
+    /// @brief group has write permission
+    group_write = 020,
+    /// @brief group has execution permission
+    group_exec = 010,
+    /// @brief group has all permissions
+    group_all = 070,
+
+    /// @brief others have read permission
+    others_read = 04,
+    /// @brief others have write permission
+    others_write = 02,
+    /// @brief others have execution permission
+    others_exec = 01,
+    /// @brief others have all permissions
+    others_all = 07,
+
+    /// @brief all permissions for everyone
+    all = 0777,
+
+    /// @brief set uid bit
+    set_uid = 04000,
+    /// @brief set gid bit
+    set_gid = 02000,
+    /// @brief set sticky bit
+    sticky_bit = 01000,
+
+    /// @brief all permissions for everyone as well as uid, gid and sticky bit
+    mask = 07777
+};
+} // namespace cxx
+} // namespace iox
+
+#endif