.. _program_listing_file__tmp_ws_src_rosbag2_rosbag2_storage_mcap_include_rosbag2_storage_mcap_visibility_control.hpp:

Program Listing for File visibility_control.hpp
===============================================

|exhale_lsh| :ref:`Return to documentation for file <file__tmp_ws_src_rosbag2_rosbag2_storage_mcap_include_rosbag2_storage_mcap_visibility_control.hpp>` (``/tmp/ws/src/rosbag2/rosbag2_storage_mcap/include/rosbag2_storage_mcap/visibility_control.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright 2022 Foxglove Technologies 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.
   
   /* This header must be included by this library's headers which declare symbols
    * that are defined separately. The contents of this header change the visibility
    * of certain symbols, especially for Windows DLL usage.
    */
   
   #ifndef ROSBAG2_STORAGE_MCAP__VISIBILITY_CONTROL_HPP_
   #define ROSBAG2_STORAGE_MCAP__VISIBILITY_CONTROL_HPP_
   
   // This logic was borrowed (then namespaced) from the examples on the gcc wiki:
   //     https://gcc.gnu.org/wiki/Visibility
   
   #if defined _WIN32 || defined __CYGWIN__
     #ifdef __GNUC__
       #define ROSBAG2_STORAGE_MCAP_EXPORT __attribute__((dllexport))
       #define ROSBAG2_STORAGE_MCAP_IMPORT __attribute__((dllimport))
     #else
       #define ROSBAG2_STORAGE_MCAP_EXPORT __declspec(dllexport)
       #define ROSBAG2_STORAGE_MCAP_IMPORT __declspec(dllimport)
     #endif
     #ifdef ROSBAG2_STORAGE_MCAP_BUILDING_DLL
       #define ROSBAG2_STORAGE_MCAP_PUBLIC ROSBAG2_STORAGE_MCAP_EXPORT
     #else
       #define ROSBAG2_STORAGE_MCAP_PUBLIC ROSBAG2_STORAGE_MCAP_IMPORT
     #endif
   #else
     #define ROSBAG2_STORAGE_MCAP_EXPORT __attribute__((visibility("default")))
     #define ROSBAG2_STORAGE_MCAP_IMPORT
     #if __GNUC__ >= 4
       #define ROSBAG2_STORAGE_MCAP_PUBLIC __attribute__((visibility("default")))
     #else
       #define ROSBAG2_STORAGE_MCAP_PUBLIC
     #endif
   #endif
   
   #endif  // ROSBAG2_STORAGE_MCAP__VISIBILITY_CONTROL_HPP_