json/CMakeLists.txt

202 lines
6.5 KiB
CMake

cmake_minimum_required(VERSION 3.1)
##
## PROJECT
## name and version
##
project(nlohmann_json VERSION 3.10.5 LANGUAGES CXX)
##
## MAIN_PROJECT CHECK
## determine if nlohmann_json is built as a subproject (using add_subdirectory) or if it is the main project
##
set(MAIN_PROJECT OFF)
if (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
set(MAIN_PROJECT ON)
endif()
##
## INCLUDE
##
##
set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
include(ExternalProject)
##
## OPTIONS
##
if (POLICY CMP0077)
# Allow CMake 3.13+ to override options when using FetchContent / add_subdirectory.
cmake_policy(SET CMP0077 NEW)
endif ()
# VERSION_GREATER_EQUAL is not available in CMake 3.1
if(${MAIN_PROJECT} AND (${CMAKE_VERSION} VERSION_EQUAL 3.13 OR ${CMAKE_VERSION} VERSION_GREATER 3.13))
set(JSON_BuildTests_INIT ON)
else()
set(JSON_BuildTests_INIT OFF)
endif()
option(JSON_BuildTests "Build the unit tests when BUILD_TESTING is enabled." ${JSON_BuildTests_INIT})
option(JSON_CI "Enable CI build targets." OFF)
option(JSON_Diagnostics "Use extended diagnostic messages." OFF)
option(JSON_ImplicitConversions "Enable implicit conversions." ON)
option(JSON_LegacyDiscardedValueComparison "Enable legacy discarded value comparison." OFF)
option(JSON_Install "Install CMake targets during install step." ${MAIN_PROJECT})
option(JSON_MultipleHeaders "Use non-amalgamated version of the library." ON)
option(JSON_SystemInclude "Include as system headers (skip for clang-tidy)." OFF)
if (JSON_CI)
include(ci)
endif ()
##
## CONFIGURATION
##
include(GNUInstallDirs)
set(NLOHMANN_JSON_TARGET_NAME ${PROJECT_NAME})
set(NLOHMANN_JSON_CONFIG_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}" CACHE INTERNAL "")
set(NLOHMANN_JSON_INCLUDE_INSTALL_DIR "${CMAKE_INSTALL_INCLUDEDIR}")
set(NLOHMANN_JSON_TARGETS_EXPORT_NAME "${PROJECT_NAME}Targets")
set(NLOHMANN_JSON_CMAKE_CONFIG_TEMPLATE "cmake/config.cmake.in")
set(NLOHMANN_JSON_CMAKE_CONFIG_DIR "${CMAKE_CURRENT_BINARY_DIR}")
set(NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}ConfigVersion.cmake")
set(NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}Config.cmake")
set(NLOHMANN_JSON_CMAKE_PROJECT_TARGETS_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}Targets.cmake")
set(NLOHMANN_JSON_PKGCONFIG_INSTALL_DIR "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
if (JSON_MultipleHeaders)
set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${PROJECT_SOURCE_DIR}/include/")
message(STATUS "Using the multi-header code from ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}")
else()
set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${PROJECT_SOURCE_DIR}/single_include/")
message(STATUS "Using the single-header code from ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}")
endif()
if (NOT JSON_ImplicitConversions)
message(STATUS "Implicit conversions are disabled")
endif()
if (JSON_LegacyDiscardedValueComparison)
message(STATUS "Legacy discarded value comparison enabled")
endif()
if (JSON_Diagnostics)
message(STATUS "Diagnostics enabled")
endif()
if (JSON_SystemInclude)
set(NLOHMANN_JSON_SYSTEM_INCLUDE "SYSTEM")
endif()
##
## TARGET
## create target and add include path
##
add_library(${NLOHMANN_JSON_TARGET_NAME} INTERFACE)
add_library(${PROJECT_NAME}::${NLOHMANN_JSON_TARGET_NAME} ALIAS ${NLOHMANN_JSON_TARGET_NAME})
if (${CMAKE_VERSION} VERSION_LESS "3.8.0")
target_compile_features(${NLOHMANN_JSON_TARGET_NAME} INTERFACE cxx_range_for)
else()
target_compile_features(${NLOHMANN_JSON_TARGET_NAME} INTERFACE cxx_std_11)
endif()
target_compile_definitions(
${NLOHMANN_JSON_TARGET_NAME}
INTERFACE
$<$<NOT:$<BOOL:${JSON_ImplicitConversions}>>:JSON_USE_IMPLICIT_CONVERSIONS=0>
$<$<BOOL:${JSON_Diagnostics}>:JSON_DIAGNOSTICS=1>
$<$<BOOL:${JSON_LegacyDiscardedValueComparison}>:JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON=1>
)
target_include_directories(
${NLOHMANN_JSON_TARGET_NAME}
${NLOHMANN_JSON_SYSTEM_INCLUDE} INTERFACE
$<BUILD_INTERFACE:${NLOHMANN_JSON_INCLUDE_BUILD_DIR}>
$<INSTALL_INTERFACE:include>
)
## add debug view definition file for msvc (natvis)
if (MSVC)
set(NLOHMANN_ADD_NATVIS TRUE)
set(NLOHMANN_NATVIS_FILE "nlohmann_json.natvis")
target_sources(
${NLOHMANN_JSON_TARGET_NAME}
INTERFACE
$<INSTALL_INTERFACE:${NLOHMANN_NATVIS_FILE}>
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/${NLOHMANN_NATVIS_FILE}>
)
endif()
# Install a pkg-config file, so other tools can find this.
CONFIGURE_FILE(
"${CMAKE_CURRENT_SOURCE_DIR}/cmake/pkg-config.pc.in"
"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}.pc"
)
##
## TESTS
## create and configure the unit test target
##
if (JSON_BuildTests)
include(CTest)
enable_testing()
add_subdirectory(tests)
endif()
##
## INSTALL
## install header files, generate and install cmake config files for find_package()
##
include(CMakePackageConfigHelpers)
# use a custom package version config file instead of
# write_basic_package_version_file to ensure that it's architecture-independent
# https://github.com/nlohmann/json/issues/1697
configure_file(
"cmake/nlohmann_jsonConfigVersion.cmake.in"
${NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE}
@ONLY
)
configure_file(
${NLOHMANN_JSON_CMAKE_CONFIG_TEMPLATE}
${NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE}
@ONLY
)
if(JSON_Install)
install(
DIRECTORY ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}
DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
)
install(
FILES ${NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE} ${NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE}
DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
)
if (NLOHMANN_ADD_NATVIS)
install(
FILES ${NLOHMANN_NATVIS_FILE}
DESTINATION .
)
endif()
export(
TARGETS ${NLOHMANN_JSON_TARGET_NAME}
NAMESPACE ${PROJECT_NAME}::
FILE ${NLOHMANN_JSON_CMAKE_PROJECT_TARGETS_FILE}
)
install(
TARGETS ${NLOHMANN_JSON_TARGET_NAME}
EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
INCLUDES DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
)
install(
EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
NAMESPACE ${PROJECT_NAME}::
DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
)
install(
FILES "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}.pc"
DESTINATION ${NLOHMANN_JSON_PKGCONFIG_INSTALL_DIR}
)
endif()