CMakeLists.txt

# This is the main CMake build file for the wgrib2 project.
#
# Kyle Gerheiser, Edward Hartnett, Wesley Ebisuzaki, Alyson Stahl
cmake_minimum_required(VERSION 3.15)

# Read the current version number from file VERSION.
file(STRINGS "VERSION" pVersion)

# Set up project with version number from VERSION file.
project(wgrib2 VERSION ${pVersion} LANGUAGES C)

# Provide install directories according to GNU standards.
include(GNUInstallDirs)

# Find CMake code we need.
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

# Handle user build options.
option(ENABLE_DOCS "Enable generation of doxygen-based documentation." OFF)
option(USE_NETCDF "Use NetCDF" off)
option(USE_REGEX "Use Regex?" on)
option(USE_IPOLATES "Use Ipolates" off)
option(USE_UDF "Use UDF?" off)
option(USE_OPENMP "Use OpenMP?" off)
option(USE_PROJ4 "Use Proj4?" off)
option(DISABLE_ALARM "Disable Alarm?" off)
set(USE_NAMES "NCEP")
option(USE_G2CLIB "Use with g2clib? (Enables g2c decoders.)" ON)
option(BUILD_EXTRA "Build user-contributed code" OFF)
option(FTP_TEST_FILES "Fetch and test with files on FTP site." OFF)
option(FTP_LARGE_TEST_FILES "Fetch and test with very large files on FTP site." OFF)
option(FTP_EXTRA_TEST_FILES "Fetch even more large files from FTP and test them." OFF)
# MAKE_FTN_API should only be on when building library
option(MAKE_FTN_API "add ftn api?" off)
option(DISABLE_STAT "disable posix feature" off)
set(BUILD_COMMENTS "stock build")

option(BUILD_LIB "Build wgrib2 library?" on)
# if BUILD_LIB, then code is compiled as relocatable
option(BUILD_SHARED_LIB "Build shared library?" on)
# To create libwgrib2.so for python, you have to build with BUILD_SHARED_LIB off
# and manually create libwgrib2.so from the needed *.a files

option(BUILD_WGRIB "Build wgrib code?" on)

if (MAKE_FTN_API OR USE_IPOLATES)
  enable_language(Fortran)
endif()

# Developers can use this option to specify a local directory which
# holds the test files. They will be copied instead of fetching the
# files via FTP.
SET(TEST_FILE_DIR "." CACHE STRING "Check this directory for test files before using FTP.")
message(STATUS "Finding test data files in directory ${TEST_FILE_DIR}.")

# Set default install path if not provided.
if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
  set(CMAKE_INSTALL_PREFIX
    "${CMAKE_BINARY_DIR}/install"
    CACHE PATH "default install path" FORCE)
endif()

if (BUILD_SHARED_LIB AND NOT BUILD_LIB)
   message(FATAL_ERROR "BUILD_SHARED_LIB is on but BUILD_LIB is off")
endif()

if(MAKE_FTN_API AND NOT BUILD_LIB)
  message(FATAL_ERROR "MAKE_FTN_API should only be on when building library")
endif()

# If user wants to use NCEPLIBS-ip, find it and the sp library.
message(STATUS "Checking if the user want to use NCEPLIBS-ip...")
if(USE_IPOLATES)
  find_package(ip 5.2.0 CONFIG REQUIRED)
  list(APPEND definitions_list -DIPOLATES_LIB="ipolates_lib_d")
endif()

message(STATUS "Checking if the user want to use NetCDF...")
if(USE_NETCDF)
  find_package(NetCDF MODULE REQUIRED COMPONENTS C)
endif()

if(USE_G2CLIB)
  find_package(g2c 2.3.0 CONFIG REQUIRED)
endif()

message(STATUS "Checking if the user want to use OpenMP...")
if(USE_OPENMP)
  find_package(OpenMP REQUIRED COMPONENTS C)
endif()

# write config.h
message(STATUS "Writing config.h...")
configure_file("${PROJECT_SOURCE_DIR}/src/config.h.in" "${CMAKE_CURRENT_BINARY_DIR}/config.h")
include_directories(${CMAKE_CURRENT_BINARY_DIR})

message(STATUS "Adding wgrib2, aux_probs subdirectories...")

if (BUILD_EXTRA)
  add_subdirectory(extra)
endif()

add_subdirectory(src)
add_subdirectory(aux_progs)

if(BUILD_LIB)
  message(STATUS "Adding wgrib2 library build...")
  ### Package config
  include(CMakePackageConfigHelpers)
  set(CONFIG_INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME})

  # No need for config file if library isn't built
  export(EXPORT wgrib2_exports
    NAMESPACE wgrib2::
    FILE wgrib2-targets.cmake)

  configure_package_config_file(
    ${CMAKE_SOURCE_DIR}/cmake/PackageConfig.cmake.in ${CMAKE_BINARY_DIR}/${PROJECT_NAME}-config.cmake
    INSTALL_DESTINATION ${CONFIG_INSTALL_DESTINATION})
  install(FILES ${CMAKE_BINARY_DIR}/${PROJECT_NAME}-config.cmake
    DESTINATION ${CONFIG_INSTALL_DESTINATION})

  write_basic_package_version_file(
    ${CMAKE_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake
    VERSION ${PROJECT_VERSION}
    COMPATIBILITY AnyNewerVersion)
  install(FILES ${CMAKE_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake
    DESTINATION ${CONFIG_INSTALL_DESTINATION})

  install(EXPORT wgrib2_exports
    NAMESPACE wgrib2::
    FILE wgrib2-targets.cmake
    DESTINATION ${CONFIG_INSTALL_DESTINATION})
endif()

if (BUILD_WGRIB)
  add_subdirectory(wgrib)
endif()

#  to set compiler flags
#  see wgrib2/CMakeLists.txt
#

# Turn on unit testing.
include(CTest)
if(BUILD_TESTING)
  add_subdirectory(tests)
endif()

# Determine whether or not to generate documentation.
if(ENABLE_DOCS)
  find_package(Doxygen REQUIRED)
  add_subdirectory(docs)  
endif()