CMakeLists.txt

# vim: et ts=4 sts=4 sw=4 tw=0

# ==== Define cmake build policies that affect compilation and linkage default behaviors
#
# Set the JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION string to the newest cmake version
# policies that provide successful builds. By setting JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION
# to a value greater than the oldest policies, all policies between
# JSONCPP_OLDEST_VALIDATED_POLICIES_VERSION and CMAKE_VERSION (used for this build)
# are set to their NEW behaivor, thereby suppressing policy warnings related to policies
# between the JSONCPP_OLDEST_VALIDATED_POLICIES_VERSION and CMAKE_VERSION.
#
# CMake versions greater than the JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION policies will
# continue to generate policy warnings "CMake Warning (dev)...Policy CMP0XXX is not set:"
#
set(JSONCPP_OLDEST_VALIDATED_POLICIES_VERSION "3.8.0")
set(JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION "3.13.2")
cmake_minimum_required(VERSION ${JSONCPP_OLDEST_VALIDATED_POLICIES_VERSION})
if("${CMAKE_VERSION}" VERSION_LESS "${JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION}")
    #Set and use the newest available cmake policies that are validated to work
    set(JSONCPP_CMAKE_POLICY_VERSION "${CMAKE_VERSION}")
else()
    set(JSONCPP_CMAKE_POLICY_VERSION "${JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION}")
endif()
cmake_policy(VERSION ${JSONCPP_CMAKE_POLICY_VERSION})
#
# Now enumerate specific policies newer than JSONCPP_NEWEST_VALIDATED_POLICIES_VERSION
# that may need to be individually set to NEW/OLD
#
foreach(pnew "") # Currently Empty
    if(POLICY ${pnew})
        cmake_policy(SET ${pnew} NEW)
    endif()
endforeach()
foreach(pold "") # Currently Empty
    if(POLICY ${pold})
        cmake_policy(SET ${pold} OLD)
    endif()
endforeach()

# Ensure that CMAKE_BUILD_TYPE has a value specified for single configuration generators.
if(NOT DEFINED CMAKE_BUILD_TYPE AND NOT DEFINED CMAKE_CONFIGURATION_TYPES)
    set(CMAKE_BUILD_TYPE Release CACHE STRING
        "Choose the type of build, options are: None Debug Release RelWithDebInfo MinSizeRel Coverage.")
endif()

# ---------------------------------------------------------------------------
# use ccache if found, has to be done before project()
# ---------------------------------------------------------------------------
find_program(CCACHE_EXECUTABLE "ccache" HINTS /usr/local/bin /opt/local/bin)
if(CCACHE_EXECUTABLE)
    message(STATUS "use ccache")
    set(CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_EXECUTABLE}" CACHE PATH "ccache" FORCE)
    set(CMAKE_C_COMPILER_LAUNCHER "${CCACHE_EXECUTABLE}" CACHE PATH "ccache" FORCE)
endif()

# Note: project(VERSION XX) - the VERSION here is number, but VERSION in meson is string.
# Thus, it is better to be consistent.
project(JSONCPP
        LANGUAGES CXX)

# Set variable named ${VAR_NAME} to value ${VALUE}
function(set_using_dynamic_name VAR_NAME VALUE)
    set( "${VAR_NAME}" "${VALUE}" PARENT_SCOPE)
endfunction()

# Extract major, minor, patch from version text
# Parse a version string "X.Y.Z" and outputs
# version parts in ${OUPUT_PREFIX}_MAJOR, _MINOR, _PATCH.
# If parse succeeds then ${OUPUT_PREFIX}_FOUND is TRUE.
macro(jsoncpp_parse_version VERSION_TEXT OUPUT_PREFIX)
    set(VERSION_REGEX "[0-9]+\\.[0-9]+\\.[0-9]+(-[a-zA-Z0-9_]+)?")
    if( ${VERSION_TEXT} MATCHES ${VERSION_REGEX} )
        string(REGEX MATCHALL "[0-9]+|-([A-Za-z0-9_]+)" VERSION_PARTS ${VERSION_TEXT})
        list(GET VERSION_PARTS 0 ${OUPUT_PREFIX}_MAJOR)
        list(GET VERSION_PARTS 1 ${OUPUT_PREFIX}_MINOR)
        list(GET VERSION_PARTS 2 ${OUPUT_PREFIX}_PATCH)
        set_using_dynamic_name( "${OUPUT_PREFIX}_FOUND" TRUE )
    else( ${VERSION_TEXT} MATCHES ${VERSION_REGEX} )
        set_using_dynamic_name( "${OUPUT_PREFIX}_FOUND" FALSE )
    endif()
endmacro()

# Note: version must be updated in three places when doing a release. This
# annoying process ensures that amalgamate, CMake, and meson all report the
# correct version.
# 1. ./meson.build
# 2. ./include/json/version.h
# 3. ./CMakeLists.txt
# IMPORTANT: also update the JSONCPP_SOVERSION!!
set( JSONCPP_VERSION 00.11.0 )
set( JSONCPP_SOVERSION 23 )
jsoncpp_parse_version( ${JSONCPP_VERSION} JSONCPP_VERSION )
message(STATUS "JsonCpp Version: ${JSONCPP_VERSION_MAJOR}.${JSONCPP_VERSION_MINOR}.${JSONCPP_VERSION_PATCH}")
#if(NOT JSONCPP_VERSION_FOUND)
#    message(FATAL_ERROR "Failed to parse version string properly. Expect X.Y.Z")
#endif(NOT JSONCPP_VERSION_FOUND)

option(JSONCPP_WITH_TESTS "Compile and (for jsoncpp_check) run JsonCpp test executables" ON)
option(JSONCPP_WITH_POST_BUILD_UNITTEST "Automatically run unit-tests as a post build step" ON)
option(JSONCPP_WITH_WARNING_AS_ERROR "Force compilation to fail if a warning occurs" OFF)
option(JSONCPP_WITH_STRICT_ISO "Issue all the warnings demanded by strict ISO C and ISO C++" ON)
option(JSONCPP_WITH_PKGCONFIG_SUPPORT "Generate and install .pc files" ON)
option(JSONCPP_WITH_CMAKE_PACKAGE "Generate and install cmake package files" ON)
option(JSONCPP_WITH_EXAMPLE "Compile JsonCpp example" OFF)
option(BUILD_SHARED_LIBS "Build jsoncpp_lib as a shared library." OFF)
option(BUILD_WITH_CXX_11 "Build jsoncpp_lib with C++11 standard." ON)

##  To compatible with C++0x and C++1x
set(CMAKE_MINIMUN_CXX_STANDARD 98)
if(CMAKE_COMPILER_IS_GNUCXX)
  set(CMAKE_CXX_COMPILER "/usr/bin/g++")
  execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE CXX_VERSION)
  if(CXX_VERSION VERSION_GREATER 4.8.0)
      if(BUILD_WITH_CXX_11)
          set(CMAKE_CXX_STANDARD 11)
          message(STATUS "Compiled with C++11(or newer) standard!")
      else()
          set(CMAKE_CXX_STANDARD 98)
          message(STATUS "Compiled with C++0x standard!")
      endif()
  else()
      set(CMAKE_CXX_STANDARD 98)
      message(STATUS "Compiled with C++0x standard!")
  endif()
endif()

if (NOT CMAKE_CXX_STANDARD)
  if (BUILD_WITH_CXX_11)
    set(CMAKE_CXX_STANDARD 11)
    message(STATUS "Compiled with C++1x standard!")
  else()
    set(CMAKE_CXX_STANDARD 98)
    message(STATUS "Compiled with C++0x standard!")
  endif()
endif()

# Adhere to GNU filesystem layout conventions
include(GNUInstallDirs)

set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib" CACHE PATH "Archive output dir.")
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib" CACHE PATH "Library output dir.")
set(CMAKE_PDB_OUTPUT_DIRECTORY     "${CMAKE_BINARY_DIR}/bin" CACHE PATH "PDB (MSVC debug symbol)output dir.")
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin" CACHE PATH "Executable/dll output dir.")

set(JSONCPP_USE_SECURE_MEMORY "0" CACHE STRING "-D...=1 to use memory-wiping allocator for STL")

configure_file("${PROJECT_SOURCE_DIR}/version.in"
    "${PROJECT_BINARY_DIR}/version"
    NEWLINE_STYLE UNIX)

macro(use_compilation_warning_as_error)
    if(MSVC)
        # Only enabled in debug because some old versions of VS STL generate
        # warnings when compiled in release configuration.
        add_compile_options($<$<CONFIG:Debug>:/WX>)
    elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
        add_compile_options(-Werror)
        if(JSONCPP_WITH_STRICT_ISO)
            add_compile_options(-pedantic-errors)
        endif()
    endif()
endmacro()

# Include our configuration header
include_directories(${jsoncpp_SOURCE_DIR}/include)

if(MSVC)
    # Only enabled in debug because some old versions of VS STL generate
    # unreachable code warning when compiled in release configuration.
    add_compile_options($<$<CONFIG:Debug>:/W4>)
endif()

if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
    # using regular Clang or AppleClang
    add_compile_options(-Wall -Wconversion -Wshadow -Werror=conversion -Werror=sign-compare)
elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
    # using GCC
    add_compile_options(-Wall -Wconversion -Wshadow -Wextra)
    # not yet ready for -Wsign-conversion

    if(JSONCPP_WITH_STRICT_ISO)
        add_compile_options(-Wall)
    endif()
    if(JSONCPP_WITH_WARNING_AS_ERROR)
        add_compile_options(-Werror=conversion)
    endif()
elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Intel")
    # using Intel compiler
    add_compile_options(-Wall -Wconversion -Wshadow -Wextra -Werror=conversion)

    if(JSONCPP_WITH_STRICT_ISO AND NOT JSONCPP_WITH_WARNING_AS_ERROR)
        add_compile_options(-Wpedantic)
    endif()
endif()

if(JSONCPP_WITH_WARNING_AS_ERROR)
    use_compilation_warning_as_error()
endif()

if(JSONCPP_WITH_PKGCONFIG_SUPPORT)
    configure_file(
        "pkg-config/jsoncpp.pc.in"
        "pkg-config/jsoncpp.pc"
        @ONLY)
    install(FILES "${CMAKE_CURRENT_BINARY_DIR}/pkg-config/jsoncpp.pc"
        DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
endif()

if(JSONCPP_WITH_CMAKE_PACKAGE)
    include(CMakePackageConfigHelpers)
    install(EXPORT jsoncpp
        DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/jsoncpp
        FILE        jsoncppConfig.cmake)
    write_basic_package_version_file("${CMAKE_CURRENT_BINARY_DIR}/jsoncppConfigVersion.cmake"
        VERSION ${JSONCPP_VERSION}
        COMPATIBILITY SameMajorVersion)
    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/jsoncppConfigVersion.cmake
        DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/jsoncpp)
endif()

if(JSONCPP_WITH_TESTS)
    enable_testing()
    include(CTest)
endif()

# Build the different applications
add_subdirectory(src)

#install the includes
add_subdirectory(include)

#install the example
if(JSONCPP_WITH_EXAMPLE)
    add_subdirectory(example)
endif()