Update CMakeLists.txt

Author: Myzhar

CMakeLists.txt

@@ -1,6 +1,45 @@
 cmake_minimum_required(VERSION 3.5)
 project(zed_interfaces)
 
+################################################
+# Check the ROS2 version
+
+set(ROS2_FOUND FALSE)
+if(DEFINED ENV{ROS_DISTRO})
+    set(FOUND_ROS2_DISTRO $ENV{ROS_DISTRO})
+    set(ROS2_FOUND TRUE)
+    message("* Found ROS2 ${FOUND_ROS2_DISTRO}")
+else()
+    message("* ROS2 distro variable not set. Trying to figure it out...")
+    set(ROS2_DISTROS "ardent;crystal;dashing;eloquent;foxy;galactic;humble;rolling")
+    set(ROS2_FOUND FALSE)
+    foreach(distro ${ROS2_DISTROS})
+        if(NOT ROS2_FOUND)
+            find_path(RCLCPP_H rclcpp.hpp PATHS /opt/ros/${distro}/include/rclcpp)
+            if(RCLCPP_H)
+                message("* Found ROS2 ${distro}")
+                set(FOUND_ROS2_DISTRO ${distro})
+                set(ROS2_FOUND TRUE)
+            endif()
+        endif()        
+    endforeach()    
+endif(DEFINED ENV{ROS_DISTRO})
+
+if(ROS2_FOUND)
+    if(${FOUND_ROS2_DISTRO} STREQUAL "foxy")
+        message("* ROS2 ${FOUND_ROS2_DISTRO} is officially supported by this package.")
+        add_definitions(-DFOUND_FOXY)    
+    elseif(${FOUND_ROS2_DISTRO} STREQUAL "humble")
+        message("* ROS2 ${FOUND_ROS2_DISTRO} is officially supported by this package.")
+        add_definitions(-DFOUND_HUMBLE)
+    else()
+        message("*** WARNING *** ROS2 ${FOUND_ROS2_DISTRO} is not officially supported by this package. Correct working is not guarantee.")
+    endif()
+else()
+    message("*** WARNING *** ROS2 distro is unknown. This package could not work correctly.")
+endif()
+################################################
+
 # Default to C++14
 if(NOT CMAKE_CXX_STANDARD)
   set(CMAKE_CXX_STANDARD 14)