Merge pull request #118 from herbrechtsmeier/cmake

cmake: Export targets to package config

Author: bluca

CMakeLists.txt

@@ -3,6 +3,10 @@ project(cppzmq)
 
 find_package(ZeroMQ REQUIRED)
 
+if (ZeroMQ_FOUND AND (NOT TARGET libzmq OR NOT TARGET libzmq-static))
+  message(FATAL_ERROR "ZeroMQ version not supported!")
+endif()
+
 set (${PROJECT_NAME}_VERSION ${ZeroMQ_VERSION})
 message(STATUS "cppzmq v${${PROJECT_NAME}_VERSION}")
 
@@ -11,21 +15,40 @@ set(CPPZMQ_HEADERS
     zmq_addon.hpp
 )
 
+foreach (target cppzmq cppzmq-static)
+  add_library(${target} INTERFACE)
+  target_include_directories(${target} INTERFACE $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+                                                 $<INSTALL_INTERFACE:include>)
+endforeach()
+
+target_link_libraries(cppzmq INTERFACE libzmq)
+target_link_libraries(cppzmq-static INTERFACE libzmq-static)
+
 include(GNUInstallDirs)
 include(CMakePackageConfigHelpers)
 
+install(TARGETS cppzmq cppzmq-static
+        EXPORT ${PROJECT_NAME}-targets)
+
 install(FILES ${CPPZMQ_HEADERS}
         DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 
 # GNUInstallDirs "DATADIR" wrong here; CMake search path wants "share".
 set(CPPZMQ_CMAKECONFIG_INSTALL_DIR "share/cmake/${PROJECT_NAME}" CACHE STRING "install path for cppzmqConfig.cmake")
 
+if (NOT CMAKE_VERSION VERSION_LESS 3.0)
+  export(EXPORT ${PROJECT_NAME}-targets
+         FILE "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}Targets.cmake")
+endif()
 configure_package_config_file(${PROJECT_NAME}Config.cmake.in
                               "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
                               INSTALL_DESTINATION ${CPPZMQ_CMAKECONFIG_INSTALL_DIR})
 write_basic_package_version_file(${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake
                                  VERSION ${${PROJECT_NAME}_VERSION}
                                  COMPATIBILITY AnyNewerVersion)
+install(EXPORT ${PROJECT_NAME}-targets
+        FILE ${PROJECT_NAME}Targets.cmake
+        DESTINATION ${CPPZMQ_CMAKECONFIG_INSTALL_DIR})
 install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}Config.cmake
               ${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake
               DESTINATION ${CPPZMQ_CMAKECONFIG_INSTALL_DIR})

cppzmqConfig.cmake.in

@@ -1,4 +1,12 @@
 # cppzmq cmake module
+#
+# The following import targets are created
+#
+# ::
+#
+#   cppzmq-static
+#   cppzmq
+#
 # This module sets the following variables in your project::
 #
 # cppzmq_FOUND - true if cppzmq found on the system
@@ -8,8 +16,13 @@
 
 @PACKAGE_INIT@
 
-set(PN cppzmq)
-set_and_check(${PN}_INCLUDE_DIR "${PACKAGE_PREFIX_DIR}/@CMAKE_INSTALL_INCLUDEDIR@")
-set_and_check(${PN}_LIBRARY "@ZeroMQ_LIBRARY@")
-set_and_check(${PN}_STATIC_LIBRARY "@ZeroMQ_STATIC_LIBRARY@")
-check_required_components(${PN})
+include(CMakeFindDependencyMacro)
+find_dependency(ZeroMQ)
+
+if(NOT TARGET @PROJECT_NAME@)
+  include("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
+
+  get_target_property(@PROJECT_NAME@_INCLUDE_DIR cppzmq INTERFACE_INCLUDE_DIRECTORIES)
+  get_target_property(@PROJECT_NAME@_LIBRARY libzmq LOCATION)
+  get_target_property(@PROJECT_NAME@_STATIC_LIBRARY libzmq-static LOCATION)
+endif()