Add build with systemd log support

Author: Jackarain

CMakeLists.txt

@@ -58,6 +58,7 @@ option(ENABLE_REUSEPORT				"Build with REUSEPORT support" OFF)
 
 option(ENABLE_SYSTEM_ZLIB			"Build with system zlib support" OFF)
 option(ENABLE_SYSTEM_OPENSSL		"Build with system openssl support" OFF)
+option(ENABLE_USE_SYSTEMD_LOG		"Build with systemd log support" OFF)
 
 option(ENABLE_USE_OPENSSL			"Build with openssl support" ON)
 option(ENABLE_USE_BORINGSSL			"Build with boringssl support" OFF)
@@ -125,6 +126,12 @@ endif()
 
 ################################################################################
 
+if (ENABLE_USE_SYSTEMD_LOG)
+	add_definitions(-DUSE_SYSTEMD_LOGGING)
+endif()
+
+################################################################################
+
 if (WIN32)
 	set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")