odhcp6c: update cmake file

Now that the minimum cmake version has been bumped, the cmake file can be
modernized a bit. Although it might look like a lot of changes, most of them
are quite straightforward.

Every library is located in a consistent manner (allowing command-line
overrides of library locations, useful for local development, and also makes it
trivial to do static linking, if desired).

The compiler flags have been broken up to have one per line (making it easy in
the future to add/remove flags, which would create a simple one-line diff).

Although it might look like this bumps the C standard level, cmake is actually
smart enough to pick an earlier version if C11 isn't supported by the compiler
(quite unlikely on any versions of gcc currently in use in OpenWrt and even on
old distros).

Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1e13d2eaca2792cf5e0ab8c326e07d8c5fed279e..c4c8c2ba990584fb6fb07553134c36790b4e84f8 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,56 +1,69 @@
-cmake_minimum_required(VERSION 3.10)
+cmake_minimum_required(VERSION 3.13)
 cmake_policy(SET CMP0015 NEW)
 
+
 # Project Definition
-project(odhcp6c C)
-set(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "")
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g3 -std=c99")
-add_definitions(-D_GNU_SOURCE -Os -Wall -Werror -pedantic)
-IF(CMAKE_C_COMPILER_VERSION VERSION_GREATER 6)
-       add_definitions(-Wextra -Werror=implicit-function-declaration)
-       add_definitions(-Wformat -Werror=format-security -Werror=format-nonliteral)
-ENDIF()
-add_definitions(-Wno-unused-parameter -Wmissing-declarations)
-
-if(${EXT_PREFIX_CLASS})
-       add_definitions(-DEXT_PREFIX_CLASS=${EXT_PREFIX_CLASS})
-endif(${EXT_PREFIX_CLASS})
+project(odhcp6c LANGUAGES C)
+add_executable(${PROJECT_NAME})
+target_sources(${PROJECT_NAME} PRIVATE
+       src/odhcp6c.c
+       src/dhcpv6.c
+       src/ra.c
+       src/script.c
+)
 
-if(${EXT_CER_ID})
-       add_definitions(-DEXT_CER_ID=${EXT_CER_ID})
-endif(${EXT_CER_ID})
 
-set(SOURCES src/odhcp6c.c src/dhcpv6.c src/ra.c src/script.c)
+# Compiler Options
+set_target_properties(${PROJECT_NAME} PROPERTIES C_STANDARD 11)
+target_compile_definitions(${PROJECT_NAME} PRIVATE _GNU_SOURCE)
+target_compile_options(${PROJECT_NAME} PRIVATE -g3)
+target_compile_options(${PROJECT_NAME} PRIVATE -Os)
+target_compile_options(${PROJECT_NAME} PRIVATE -Wall)
+target_compile_options(${PROJECT_NAME} PRIVATE -Werror)
+target_compile_options(${PROJECT_NAME} PRIVATE -pedantic)
+target_compile_options(${PROJECT_NAME} PRIVATE -Wextra)
+target_compile_options(${PROJECT_NAME} PRIVATE -Werror=implicit-function-declaration)
+target_compile_options(${PROJECT_NAME} PRIVATE -Wformat)
+target_compile_options(${PROJECT_NAME} PRIVATE -Werror=format-security)
+target_compile_options(${PROJECT_NAME} PRIVATE -Werror=format-nonliteral)
+target_compile_options(${PROJECT_NAME} PRIVATE -Wno-unused-parameter)
+target_compile_options(${PROJECT_NAME} PRIVATE -Wmissing-declarations)
 
-set(LIBRARIES resolv)
 
-if(USE_LIBUBOX)
-       add_definitions(-DUSE_LIBUBOX)
+# Libraries
+target_link_libraries(${PROJECT_NAME} PRIVATE resolv)
+
+if (${USE_LIBUBOX})
+       target_compile_definitions(${PROJECT_NAME} PRIVATE USE_LIBUBOX)
+       find_path(ubox_include_dir libubox/md5.h)
+       target_include_directories(${PROJECT_NAME} PRIVATE ${ubox_include_dir})
        find_library(libubox ubox)
-       set(LIBRARIES ${LIBRARIES} ${libubox})
-       FIND_PATH(ubox_include_dir libubox/md5.h)
-       INCLUDE_DIRECTORIES(${ubox_include_dir})
-else()
-       set(SOURCES ${SOURCES} src/md5.c)
-endif()
+       target_link_libraries(${PROJECT_NAME} PRIVATE ${libubox})
+else (${USE_LIBUBOX})
+       target_sources(${PROJECT_NAME} PRIVATE src/md5.c)
+endif(${USE_LIBUBOX})
+
+
+# Optional Features
+if (${EXT_CER_ID})
+       target_compile_definitions(${PROJECT_NAME} PRIVATE EXT_CER_ID=${EXT_CER_ID})
+endif(${EXT_CER_ID})
 
-add_executable(odhcp6c ${SOURCES})
+if (${EXT_PREFIX_CLASS})
+       target_compile_definitions(${PROJECT_NAME} PRIVATE EXT_PREFIX_CLASS=${EXT_PREFIX_CLASS})
+endif(${EXT_PREFIX_CLASS})
 
-target_link_libraries(odhcp6c ${LIBRARIES})
 
 # Installation
-include(GNUInstallDirs)
-install(TARGETS odhcp6c DESTINATION "${CMAKE_INSTALL_SBINDIR}")
+install(TARGETS ${PROJECT_NAME} DESTINATION sbin/)
+
 
 # Packaging information
 set(CPACK_PACKAGE_VERSION "1")
 set(CPACK_PACKAGE_CONTACT "Steven Barth <[email protected]>")
-set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "6ac")
+set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "${PROJECT_NAME}")
 set(CPACK_GENERATOR "DEB;RPM;STGZ")
 set(CPACK_STRIP_FILES true)
-
 SET(CPACK_DEBIAN_PACKAGE_VERSION ${CPACK_PACKAGE_VERSION})
 set(CPACK_PACKAGE_FILE_NAME "${PROJECT_NAME}_${CPACK_DEBIAN_PACKAGE_VERSION}")
-
 include(CPack)
-