cpp/CMakeLists.txt

CMAKE_MINIMUM_REQUIRED (VERSION 3.12)

LIST (APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

INCLUDE (cpp17)
INCLUDE (subdirs)
INCLUDE (openssl)
INCLUDE (version)

# use global flags only for standalone build
IF ("${CMAKE_CURRENT_SOURCE_DIR}" STREQUAL "${CMAKE_SOURCE_DIR}")
    OPTION (BUILD_BENCHMARK "Build benchmark" OFF)
    OPTION (BUILD_TESTS "Build tests" OFF)
    OPTION (BUILD_SHARED_LIBS "Build shared libs" OFF)
ENDIF ()
OPTION (WITH_OPENSSL "Use OpenSSL for TLS connections" OFF)
OPTION (WITH_SYSTEM_ABSEIL "Use system ABSEIL" OFF)
OPTION (WITH_SYSTEM_LZ4 "Use system LZ4" OFF)
OPTION (WITH_SYSTEM_CITYHASH "Use system cityhash" OFF)
OPTION (WITH_SYSTEM_ZSTD "Use system ZSTD" OFF)
OPTION (DEBUG_DEPENDENCIES "Print debug info about dependencies duting build" ON)
OPTION (CHECK_VERSION "Check that version number corresponds to git tag, usefull in CI/CD to validate that new version published on GitHub has same version in sources" OFF)
OPTION (DISABLE_CLANG_LIBC_WORKAROUND "Disable linking compiler-rt & gcc_s if using clang & libstdc++" OFF)
OPTION (DS_MAP_BOOL_TO_UINT8 "Map Datastore Bool type to UInt8 instead of exposing a distinct Bool API." ON)

PROJECT (DATASTORE-CLIENT
    VERSION "${DATASTORE_CPP_VERSION}"
    DESCRIPTION "Datastore C++ client library"
)

USE_CXX17 ()
USE_OPENSSL ()

IF (CHECK_VERSION)
    datastore_cpp_check_library_version(FATAL_ERROR)
ENDIF ()

IF (NOT CMAKE_BUILD_TYPE)
    SET (CMAKE_BUILD_TYPE "RelWithDebInfo")
ENDIF ()

IF (UNIX)
    IF (NOT APPLE)
        SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
    ENDIF ()
    SET (CMAKE_EXE_LINKER_FLAGS, "${CMAKE_EXE_LINKER_FLAGS} -lpthread")
    # -Wpedantic makes int128 support somewhat harder and less performant (by not allowing builtin __int128)
    # -Wno-deprecated-declarations to produce less cluttered output when building library itself (`deprecated` attributes are for library users)
    SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Werror -Wno-deprecated-declarations")
ENDIF ()

IF (APPLE OR MSVC)
    IF(BUILD_SHARED_LIBS)
        MESSAGE(FATAL "Does not support shared on this platform")
    ENDIF()
ENDIF()

IF (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
    INCLUDE (CheckCXXSourceCompiles)

    CHECK_CXX_SOURCE_COMPILES("#include <bits/c++config.h>\nint main() { return __GLIBCXX__ != 0; }"
                              CLANG_WITH_LIB_STDCXX)
ENDIF ()

IF (CLANG_WITH_LIB_STDCXX)
    # there is a problem with __builtin_mul_overflow call at link time
    # the error looks like: ... undefined reference to `__muloti4' ...
    # caused by clang bug https://bugs.llvm.org/show_bug.cgi?id=16404
    # explicit linking to compiler-rt allows to workaround the problem
    SET (CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} --rtlib=compiler-rt")
    SET (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} --rtlib=compiler-rt")

    # some workaround for linking issues on linux:
    # /usr/bin/ld: CMakeFiles/simple-test.dir/main.cpp.o: undefined reference to symbol '_Unwind_Resume@@GCC_3.0'
    # /usr/bin/ld: /lib/x86_64-linux-gnu/libgcc_s.so.1: error adding symbols: DSO missing from command line
    # FIXME: that workaround breaks clang build on mingw
    SET (CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -lgcc_s")
    SET (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -lgcc_s")
ENDIF ()

IF (WITH_SYSTEM_ABSEIL)
    FIND_PACKAGE(absl REQUIRED)
ELSE ()
    INCLUDE_DIRECTORIES (contrib/absl)
    SUBDIRS (contrib/absl/absl)
ENDIF ()

IF (WITH_SYSTEM_LZ4)
    FIND_PACKAGE(lz4 REQUIRED)
ELSE ()
    INCLUDE_DIRECTORIES (contrib/lz4/lz4)
    SUBDIRS (contrib/lz4/lz4)
ENDIF ()

IF (WITH_SYSTEM_CITYHASH)
    FIND_PACKAGE(cityhash REQUIRED)
ELSE ()
    INCLUDE_DIRECTORIES (contrib/cityhash/cityhash)
    SUBDIRS (contrib/cityhash/cityhash)
ENDIF ()

IF (WITH_SYSTEM_ZSTD)
    FIND_PACKAGE(zstd REQUIRED)
ELSE ()
    INCLUDE_DIRECTORIES (contrib/zstd/zstd)
    SUBDIRS (contrib/zstd/zstd)
ENDIF ()

SUBDIRS (
    datastore
)

IF (BUILD_BENCHMARK)
    SUBDIRS (bench)
ENDIF (BUILD_BENCHMARK)

IF (BUILD_TESTS)
    INCLUDE_DIRECTORIES (contrib/gtest/include contrib/gtest)
    SUBDIRS (
        contrib/gtest
        tests/simple
        ut
    )
ENDIF (BUILD_TESTS)

if(DEBUG_DEPENDENCIES)
    function(print_target_properties target)
        MESSAGE("${target} properties:")
        set(properties "${ARGN}")
        foreach(property_name ${properties})
            get_target_property(PROPERTY ${target} ${property_name})
            MESSAGE(NOTICE "\t${property_name} : ${PROPERTY}")
        endforeach()

        # Can't get path to the target file at configure time,
        # so have to create a target to fetch that info at generate time.
        string(REPLACE ":" "_" target_plain_name ${target})
        add_custom_target(${target_plain_name}_print_debug_info COMMAND ${CMAKE_COMMAND} -E echo "${target} : $<TARGET_FILE:${target}>")
        add_dependencies(datastore-cpp-lib ${target_plain_name}_print_debug_info)
    endfunction()

    function(print_target_debug_info target)
        print_target_properties(${target}
            INCLUDE_DIRECTORIES
            BINARY_DIR
            INTERFACE_INCLUDE_DIRECTORIES
            INTERFACE_LINK_LIBRARIES
            LINK_LIBRARIES
            LINK_LIBRARIES_ONLY_TARGETS
            IMPORTED_LOCATION
        )
    endfunction()

    print_target_debug_info(absl::int128)
    print_target_debug_info(cityhash::cityhash)
    print_target_debug_info(lz4::lz4)
    print_target_debug_info(zstd::zstd)
endif()