cmake: support build without libconfig

common/CMakeLists.txt

@@ -83,4 +83,6 @@ if(TOPLEVEL_PROJECT)
     message(STATUS "  VARIANT:         ${CMAKE_PROJECT_VARIANT}")
     message(STATUS "  BUILD_ID:        ${CMAKE_PROJECT_BUILD_ID}")
     message(STATUS "  BUILD_DATE:      ${CMAKE_PROJECT_BUILD_DATE}")
+    message(STATUS "  ARCH:            ${CMAKE_SYSTEM_PROCESSOR}")
+    message(STATUS "  OS:              ${CMAKE_SYSTEM_NAME}")
 endif()

common/include/villas/compat.h

@@ -37,7 +37,7 @@ int json_dumpfd(const json_t *json, int output, size_t flags);
 json_t *json_loadfd(int input, size_t flags, json_error_t *error);
 #endif
 
-#if defined(LIBCONFIG_FOUND) && (LIBCONFIG_VER_MAJOR <= 1) && (LIBCONFIG_VER_MINOR < 5)
+#if defined(WITH_CONFIG) && (LIBCONFIG_VER_MAJOR <= 1) && (LIBCONFIG_VER_MINOR < 5)
   #include <libconfig.h>
 
   #define config_setting_lookup config_lookup_from

common/include/villas/config.h.in

@@ -44,9 +44,6 @@
 #define PROJECT_NAME		"@CMAKE_PROJECT_DESCRIPTION@"
 #define USER_AGENT		"@CMAKE_PROJECT_DESCRIPTION@ (@CMAKE_PROJECT_BUILD_ID@)"
 
-/* Available Libraries */
-#cmakedefine LIBCONFIG_FOUND
-
 /* Paths */
 #define PREFIX			"@CMAKE_INSTALL_PREFIX@"
 #define PLUGIN_PATH		"@CMAKE_INSTALL_PREFIX@/share/villas/node/plugins"

common/lib/CMakeLists.txt

@@ -77,7 +77,6 @@ target_include_directories(villas-common PUBLIC
 
 target_link_libraries(villas-common PUBLIC
 	PkgConfig::JANSSON
-	PkgConfig::LIBCONFIG
 	${OPENSSL_LIBRARIES}
 	${CURL_LIBRARIES}
 	${CMAKE_DL_LIBS}
@@ -86,6 +85,12 @@ target_link_libraries(villas-common PUBLIC
 	stdc++
 )
 
+if(WITH_CONFIG)
+	target_link_libraries(villas-common PUBLIC
+		PkgConfig::LIBCONFIG
+	)
+endif()
+
 target_compile_definitions(villas-common PUBLIC
 	-D__STDC_FORMAT_MACROS -D_GNU_SOURCE
 )