Better dependedency management

CMakeLists.txt

@@ -124,6 +124,7 @@ endmacro()
 
 if(OPENMC_USE_DAGMC)
   find_package(DAGMC REQUIRED PATH_SUFFIXES lib/cmake)
+  set(OPENMC_DAGMC_DIR ${DAGMC_DIR})
   if (${DAGMC_VERSION} VERSION_LESS 3.2.0)
     message(FATAL_ERROR "Discovered DAGMC Version: ${DAGMC_VERSION}."
       "Please update DAGMC to version 3.2.0 or greater.")
@@ -149,6 +150,7 @@ endif()
 #===============================================================================
 
 find_package(PNG)
+set(OPENMC_USE_PNG ${PNG_FOUND})
 
 #===============================================================================
 # HDF5 for binary output
@@ -243,11 +245,18 @@ endif()
 if(OPENMC_FORCE_VENDORED_LIBS)
   add_subdirectory(vendor/pugixml)
   set_target_properties(pugixml PROPERTIES CXX_STANDARD 14 CXX_EXTENSIONS OFF)
+  set(OPENMC_USES_VENDORED_PUGIXML TRUE)
+  set(OPENMC_PUGIXML_DIR "")
 else()
   find_package_write_status(pugixml)
   if (NOT pugixml_FOUND)
     add_subdirectory(vendor/pugixml)
     set_target_properties(pugixml PROPERTIES CXX_STANDARD 14 CXX_EXTENSIONS OFF)
+    set(OPENMC_USES_VENDORED_PUGIXML TRUE)
+    set(OPENMC_PUGIXML_DIR "")
+  else()
+    set(OPENMC_USES_VENDORED_PUGIXML FALSE)
+    set(OPENMC_PUGIXML_DIR "${pugixml_DIR}")
   endif()
 endif()
 
@@ -258,11 +267,18 @@ endif()
 if(OPENMC_FORCE_VENDORED_LIBS)
   set(FMT_INSTALL ON CACHE BOOL "Generate the install target.")
   add_subdirectory(vendor/fmt)
+  set(OPENMC_USES_VENDORED_FMT TRUE)
+  set(OPENMC_FMT_DIR "")
 else()
   find_package_write_status(fmt)
   if (NOT fmt_FOUND)
     set(FMT_INSTALL ON CACHE BOOL "Generate the install target.")
     add_subdirectory(vendor/fmt)
+    set(OPENMC_USES_VENDORED_FMT TRUE)
+    set(OPENMC_FMT_DIR "")
+  else()
+    set(OPENMC_USES_VENDORED_FMT FALSE)
+    set(OPENMC_FMT_DIR "${fmt_DIR}")
   endif()
 endif()
 
@@ -274,12 +290,29 @@ if(OPENMC_FORCE_VENDORED_LIBS)
   add_subdirectory(vendor/xtl)
   set(xtl_DIR ${CMAKE_CURRENT_BINARY_DIR}/vendor/xtl)
   add_subdirectory(vendor/xtensor)
+  set(OPENMC_USES_VENDORED_XTENSOR TRUE)
+  set(OPENMC_XTENSOR_DIR "")
+  set(OPENMC_XTL_DIR "")
 else()
   find_package_write_status(xtensor)
   if (NOT xtensor_FOUND)
     add_subdirectory(vendor/xtl)
     set(xtl_DIR ${CMAKE_CURRENT_BINARY_DIR}/vendor/xtl)
     add_subdirectory(vendor/xtensor)
+    set(OPENMC_USES_VENDORED_XTENSOR TRUE)
+    set(OPENMC_XTENSOR_DIR "")
+    set(OPENMC_XTL_DIR "")
+  else()
+    set(OPENMC_USES_VENDORED_XTENSOR FALSE)
+    set(OPENMC_XTENSOR_DIR "${xtensor_DIR}")
+    # xtl is a dependency of xtensor, so its DIR should be available too
+    if(DEFINED xtl_DIR)
+      set(OPENMC_XTL_DIR "${xtl_DIR}")
+    else()
+      # If xtl_DIR isn't set, it's likely in the same prefix as xtensor.
+      # We'll rely on the xtensor hint to find it.
+      set(OPENMC_XTL_DIR "${xtensor_DIR}")
+    endif()
   endif()
 endif()
 
@@ -580,9 +613,7 @@ add_custom_command(TARGET libopenmc POST_BUILD
 #===============================================================================
 # Install executable, scripts, manpage, license
 #===============================================================================
-
-configure_file(cmake/OpenMCConfig.cmake.in "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/OpenMCConfig.cmake" @ONLY)
-configure_file(cmake/OpenMCConfigVersion.cmake.in "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/OpenMCConfigVersion.cmake" @ONLY)
+include(CMakePackageConfigHelpers)
 
 set(INSTALL_CONFIGDIR ${CMAKE_INSTALL_LIBDIR}/cmake/OpenMC)
 install(TARGETS openmc libopenmc
@@ -596,10 +627,24 @@ install(EXPORT openmc-targets
   NAMESPACE OpenMC::
   DESTINATION ${INSTALL_CONFIGDIR})
 
+configure_package_config_file(
+    "cmake/OpenMCConfig.cmake.in"
+    "${CMAKE_BINARY_DIR}/${CMAKE_FILES_DIRECTORY}/OpenMCConfig.cmake"
+    INSTALL_DESTINATION ${INSTALL_CONFIGDIR}
+)
+
+write_basic_package_version_file(
+    "${CMAKE_BINARY_DIR}/${CMAKE_FILES_DIRECTORY}/OpenMCConfigVersion.cmake"
+    VERSION ${OPENMC_VERSION}
+    COMPATIBILITY AnyNewerVersion
+)
+
 install(FILES
-  "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/OpenMCConfig.cmake"
-  "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/OpenMCConfigVersion.cmake"
-  DESTINATION ${INSTALL_CONFIGDIR})
+    "${CMAKE_BINARY_DIR}/${CMAKE_FILES_DIRECTORY}/OpenMCConfig.cmake"
+    "${CMAKE_BINARY_DIR}/${CMAKE_FILES_DIRECTORY}/OpenMCConfigVersion.cmake"
+    DESTINATION "${INSTALL_CONFIGDIR}"
+)
+
 install(FILES man/man1/openmc.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)
 install(FILES LICENSE DESTINATION "${CMAKE_INSTALL_DOCDIR}" RENAME copyright)
 install(DIRECTORY include/ DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})

cmake/OpenMCConfig.cmake.in

@@ -1,14 +1,30 @@
-get_filename_component(OpenMC_CMAKE_DIR "${CMAKE_CURRENT_LIST_FILE}" DIRECTORY)
+@PACKAGE_INIT@
 
-# Compute the install prefix from this file's location
-get_filename_component(_OPENMC_PREFIX "${OpenMC_CMAKE_DIR}/../../.." ABSOLUTE)
+include("${CMAKE_CURRENT_LIST_DIR}/OpenMCConfigVersion.cmake")
+include(CMakeFindDependencyMacro)
 
-find_package(fmt CONFIG REQUIRED HINTS ${_OPENMC_PREFIX})
-find_package(pugixml CONFIG REQUIRED HINTS ${_OPENMC_PREFIX})
-find_package(xtl CONFIG REQUIRED HINTS ${_OPENMC_PREFIX})
-find_package(xtensor CONFIG REQUIRED HINTS ${_OPENMC_PREFIX})
+if (@OPENMC_USES_VENDORED_FMT@)
+  find_dependency(fmt CONFIG REQUIRED HINTS "${PACKAGE_PREFIX_DIR}")
+else()
+  find_dependency(fmt CONFIG REQUIRED HINTS "@OPENMC_FMT_DIR@")
+endif()
+if (@OPENMC_USES_VENDORED_PUGIXML@)
+  find_dependency(pugixml CONFIG REQUIRED HINTS "${PACKAGE_PREFIX_DIR}")
+else()
+  find_dependency(pugixml CONFIG REQUIRED HINTS "@OPENMC_PUGIXML_DIR@")
+endif()
+if (@OPENMC_USES_VENDORED_XTENSOR@)
+  find_dependency(xtl CONFIG REQUIRED HINTS "${PACKAGE_PREFIX_DIR}")
+else()
+  find_dependency(xtl CONFIG REQUIRED HINTS "@OPENMC_XTL_DIR@")
+endif()
+if (@OPENMC_USES_VENDORED_XTENSOR@)
+  find_dependency(xtensor CONFIG REQUIRED HINTS "${PACKAGE_PREFIX_DIR}")
+else()
+  find_dependency(xtensor CONFIG REQUIRED HINTS "@OPENMC_XTENSOR_DIR@")
+endif()
 if(@OPENMC_USE_DAGMC@)
-  find_package(DAGMC REQUIRED HINTS @DAGMC_DIR@)
+  find_dependency(DAGMC REQUIRED HINTS @OPENMC_DAGMC_DIR@)
 endif()
 
 if(@OPENMC_USE_LIBMESH@)
@@ -18,20 +34,24 @@ if(@OPENMC_USE_LIBMESH@)
   pkg_check_modules(LIBMESH REQUIRED @LIBMESH_PC_FILE@>=1.7.0 IMPORTED_TARGET)
 endif()
 
-find_package(PNG)
-
-if(NOT TARGET OpenMC::libopenmc)
-  include("${OpenMC_CMAKE_DIR}/OpenMCTargets.cmake")
+if(@OPENMC_USE_PNG@)
+  find_dependency(PNG)
 endif()
 
 if(@OPENMC_USE_MPI@)
-  find_package(MPI REQUIRED)
+  find_dependency(MPI REQUIRED)
 endif()
 
 if(@OPENMC_USE_OPENMP@)
-  find_package(OpenMP REQUIRED)
+  find_dependency(OpenMP REQUIRED)
 endif()
 
 if(@OPENMC_USE_UWUW@ AND NOT ${DAGMC_BUILD_UWUW})
   message(FATAL_ERROR "UWUW is enabled in OpenMC but the DAGMC installation discovered was not configured with UWUW.")
 endif()
+
+include("${CMAKE_CURRENT_LIST_DIR}/OpenMCTargets.cmake")
+
+if(NOT OpenMC_FIND_QUIETLY)
+    message(STATUS "Found OpenMC: ${PACKAGE_VERSION} (found in ${PACKAGE_PREFIX_DIR})")
+endif()