15.5.2.3 Compiling a foreign extension using CMake

If the package is more complicated, a simple Makefile typically does not suffice. In this case we have two options. One is to use the GNU autoconf or automake. However, cmake is getting more popular and provides much better support for non-POSIX platforms, e.g., Windows. This section discusses building the same package as section 15.5.2.1 using cmake.

To use cmake, add the content below as the file CMakeLists.txt to the root directory of the pack. SWI-Prolog ships with a cmake include file named swipl.cmake that deals with most of the configuration issues. Comments in the file below explain the various steps of the process.

cmake_minimum_required(VERSION 3.5)
project(swipl-pack-environ)

# Include swipl.cmake from the running SWI-Prolog's home
list(INSERT CMAKE_MODULE_PATH 0 $ENV{SWIPL_HOME_DIR}/cmake)
include(swipl)

# Create the library as a CMake module
add_library(environ MODULE c/environ.c)

# Link the library to SWI-Prolog.  This also removes the `lib` prefix
# from the target on systems that define a common library file prefix
target_link_swipl(environ)

# Install the foreign taget. `${swipl_module_dir}` contains the
# directory for installing modules for this architecture.

install(TARGETS environ
        DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/${swipl_module_dir})

# Run  tests.  This  is  executed   before    the   pack  is  installed.
# swipl_test(name) runs Prolog with the command line below.
#
#    swipl -p foreign=${CMAKE_CURRENT_SOURCE_DIR}/${swipl_module_dir} \
#          -p library=${CMAKE_CURRENT_SOURCE_DIR}/prolog \
#          --on-error=status \
#          -g test_${name} \
#          -t halt \
#          ${CMAKE_CURRENT_SOURCE_DIR}/test/test_${name}.pl
#
# This  implies  that  a  test  `name`  must    be  defined  in  a  file
# `test/test_${name}.pl`, which exports a  predicate `test_${name}`. The
# test succeeds if this predicate  succeeds   and  no error messages are
# printed.

enable_testing()
swipl_add_test(environ)