# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.

cmake_minimum_required(VERSION 2.8.12.2 FATAL_ERROR)
if(POLICY CMP0025)
  cmake_policy(SET CMP0025 NEW)
endif()
if(POLICY CMP0053)
  cmake_policy(SET CMP0053 NEW)
endif()
project(CMake)

# Make sure we can find internal find_package modules only used for
# building CMake and not for shipping externally
list(INSERT CMAKE_MODULE_PATH 0 ${CMake_SOURCE_DIR}/Source/Modules)

if(CMAKE_BOOTSTRAP)
  # Running from bootstrap script.  Set local variable and remove from cache.
  set(CMAKE_BOOTSTRAP 1)
  unset(CMAKE_BOOTSTRAP CACHE)
endif()

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  set(CMake_BIN_DIR ${CMake_BINARY_DIR}/bin)
endif()

if(CMake_GUI_DISTRIBUTE_WITH_Qt_LGPL)
  if(CMake_GUI_DISTRIBUTE_WITH_Qt_LGPL MATCHES "^3|2\\.1$")
    set(USE_LGPL "${CMake_GUI_DISTRIBUTE_WITH_Qt_LGPL}")
  else()
    set(USE_LGPL "2.1")
  endif()
else()
  set(USE_LGPL "")
endif()

if("${CMake_SOURCE_DIR}" STREQUAL "${CMAKE_SOURCE_DIR}")
  # Disallow architecture-specific try_run.  It may not run on the host.
  macro(TRY_RUN)
    if(CMAKE_TRY_COMPILE_OSX_ARCHITECTURES)
      message(FATAL_ERROR "TRY_RUN not allowed with CMAKE_TRY_COMPILE_OSX_ARCHITECTURES=[${CMAKE_TRY_COMPILE_OSX_ARCHITECTURES}]")
    else()
      _TRY_RUN(${ARGV})
    endif()
  endmacro()
endif()

# Use most-recent available language dialects with GNU and Clang
if(NOT DEFINED CMAKE_C_STANDARD AND NOT CMake_NO_C_STANDARD)
  include(${CMake_SOURCE_DIR}/Source/Checks/cm_c11_thread_local.cmake)
  if(NOT CMake_C11_THREAD_LOCAL_BROKEN)
    set(CMAKE_C_STANDARD 11)
  else()
    set(CMAKE_C_STANDARD 99)
  endif()
endif()
if(NOT DEFINED CMAKE_CXX_STANDARD AND NOT CMake_NO_CXX_STANDARD)
  include(${CMake_SOURCE_DIR}/Source/Checks/cm_cxx14_cstdio.cmake)
  if(NOT CMake_CXX14_CSTDIO_BROKEN)
    set(CMAKE_CXX_STANDARD 14)
  else()
    set(CMAKE_CXX_STANDARD 11)
  endif()
endif()
if(NOT CMake_TEST_EXTERNAL_CMAKE)
  include(${CMake_SOURCE_DIR}/Source/Checks/cm_cxx_features.cmake)
endif()

# set the internal encoding of CMake to UTF-8
set(KWSYS_ENCODING_DEFAULT_CODEPAGE CP_UTF8)

# option to use COMPONENT with install command
option(CMake_INSTALL_COMPONENTS "Using components when installing" OFF)
mark_as_advanced(CMake_INSTALL_COMPONENTS)
macro(CMake_OPTIONAL_COMPONENT NAME)
  if(CMake_INSTALL_COMPONENTS)
    set(COMPONENT COMPONENT ${NAME})
  else()
    set(COMPONENT)
  endif()
endmacro()

# option to disable installing 3rd-party dependencies
option(CMake_INSTALL_DEPENDENCIES
  "Whether to install 3rd-party runtime dependencies" OFF)
mark_as_advanced(CMake_INSTALL_DEPENDENCIES)

# option to build reference for CMake developers
option(CMake_BUILD_DEVELOPER_REFERENCE
  "Build CMake Developer Reference" OFF)
mark_as_advanced(CMake_BUILD_DEVELOPER_REFERENCE)

#-----------------------------------------------------------------------
# a macro to deal with system libraries, implemented as a macro
# simply to improve readability of the main script
#-----------------------------------------------------------------------
macro(CMAKE_HANDLE_SYSTEM_LIBRARIES)
  # Options have dependencies.
  include(CMakeDependentOption)

  # Optionally use system xmlrpc.  We no longer build or use it by default.
  option(CTEST_USE_XMLRPC "Enable xmlrpc submission method in CTest." OFF)
  mark_as_advanced(CTEST_USE_XMLRPC)

  # Allow the user to enable/disable all system utility library options by
  # defining CMAKE_USE_SYSTEM_LIBRARIES or CMAKE_USE_SYSTEM_LIBRARY_${util}.
  set(UTILITIES BZIP2 CURL EXPAT FORM JSONCPP LIBARCHIVE LIBLZMA LIBRHASH LIBUV ZLIB)
  foreach(util ${UTILITIES})
    if(NOT DEFINED CMAKE_USE_SYSTEM_LIBRARY_${util}
        AND DEFINED CMAKE_USE_SYSTEM_LIBRARIES)
      set(CMAKE_USE_SYSTEM_LIBRARY_${util} "${CMAKE_USE_SYSTEM_LIBRARIES}")
    endif()
    if(DEFINED CMAKE_USE_SYSTEM_LIBRARY_${util})
      if(CMAKE_USE_SYSTEM_LIBRARY_${util})
        set(CMAKE_USE_SYSTEM_LIBRARY_${util} ON)
      else()
        set(CMAKE_USE_SYSTEM_LIBRARY_${util} OFF)
      endif()
      if(CMAKE_BOOTSTRAP)
        unset(CMAKE_USE_SYSTEM_LIBRARY_${util} CACHE)
      endif()
      string(TOLOWER "${util}" lutil)
      set(CMAKE_USE_SYSTEM_${util} "${CMAKE_USE_SYSTEM_LIBRARY_${util}}"
        CACHE BOOL "Use system-installed ${lutil}" FORCE)
    else()
      set(CMAKE_USE_SYSTEM_LIBRARY_${util} OFF)
    endif()
  endforeach()
  if(CMAKE_BOOTSTRAP)
    unset(CMAKE_USE_SYSTEM_LIBRARIES CACHE)
  endif()

  # Optionally use system utility libraries.
  option(CMAKE_USE_SYSTEM_LIBARCHIVE "Use system-installed libarchive" "${CMAKE_USE_SYSTEM_LIBRARY_LIBARCHIVE}")
  CMAKE_DEPENDENT_OPTION(CMAKE_USE_SYSTEM_CURL "Use system-installed curl"
    "${CMAKE_USE_SYSTEM_LIBRARY_CURL}" "NOT CTEST_USE_XMLRPC" ON)
  CMAKE_DEPENDENT_OPTION(CMAKE_USE_SYSTEM_EXPAT "Use system-installed expat"
    "${CMAKE_USE_SYSTEM_LIBRARY_EXPAT}" "NOT CTEST_USE_XMLRPC" ON)
  CMAKE_DEPENDENT_OPTION(CMAKE_USE_SYSTEM_ZLIB "Use system-installed zlib"
    "${CMAKE_USE_SYSTEM_LIBRARY_ZLIB}" "NOT CMAKE_USE_SYSTEM_LIBARCHIVE;NOT CMAKE_USE_SYSTEM_CURL" ON)
  CMAKE_DEPENDENT_OPTION(CMAKE_USE_SYSTEM_BZIP2 "Use system-installed bzip2"
    "${CMAKE_USE_SYSTEM_LIBRARY_BZIP2}" "NOT CMAKE_USE_SYSTEM_LIBARCHIVE" ON)
  CMAKE_DEPENDENT_OPTION(CMAKE_USE_SYSTEM_LIBLZMA "Use system-installed liblzma"
    "${CMAKE_USE_SYSTEM_LIBRARY_LIBLZMA}" "NOT CMAKE_USE_SYSTEM_LIBARCHIVE" ON)
  option(CMAKE_USE_SYSTEM_FORM "Use system-installed libform" "${CMAKE_USE_SYSTEM_LIBRARY_FORM}")
  option(CMAKE_USE_SYSTEM_JSONCPP "Use system-installed jsoncpp" "${CMAKE_USE_SYSTEM_LIBRARY_JSONCPP}")
  option(CMAKE_USE_SYSTEM_LIBRHASH "Use system-installed librhash" "${CMAKE_USE_SYSTEM_LIBRARY_LIBRHASH}")
  option(CMAKE_USE_SYSTEM_LIBUV "Use system-installed libuv" "${CMAKE_USE_SYSTEM_LIBRARY_LIBUV}")

  # For now use system KWIML only if explicitly requested rather
  # than activating via the general system libs options.
  option(CMAKE_USE_SYSTEM_KWIML "Use system-installed KWIML" OFF)
  mark_as_advanced(CMAKE_USE_SYSTEM_KWIML)

  # Mention to the user what system libraries are being used.
  foreach(util ${UTILITIES} KWIML)
    if(CMAKE_USE_SYSTEM_${util})
      message(STATUS "Using system-installed ${util}")
    endif()
  endforeach()

  # Inform utility library header wrappers whether to use system versions.
  configure_file(${CMake_SOURCE_DIR}/Utilities/cmThirdParty.h.in
    ${CMake_BINARY_DIR}/Utilities/cmThirdParty.h
    @ONLY)

endmacro()

#-----------------------------------------------------------------------
# a macro to determine the generator and ctest executable to use
# for testing. Simply to improve readability of the main script.
#-----------------------------------------------------------------------
macro(CMAKE_SETUP_TESTING)
  if(BUILD_TESTING)
    set(CMAKE_TEST_SYSTEM_LIBRARIES 0)
    foreach(util CURL EXPAT XMLRPC ZLIB)
      if(CMAKE_USE_SYSTEM_${util})
        set(CMAKE_TEST_SYSTEM_LIBRARIES 1)
      endif()
    endforeach()

    # This variable is set by cmake, however to
    # test cmake we want to make sure that
    # the ctest from this cmake is used for testing
    # and not the ctest from the cmake building and testing
    # cmake.
    if(CMake_TEST_EXTERNAL_CMAKE)
      set(CMAKE_CTEST_COMMAND "${CMake_TEST_EXTERNAL_CMAKE}/ctest")
      set(CMAKE_CMAKE_COMMAND "${CMake_TEST_EXTERNAL_CMAKE}/cmake")
      set(CMAKE_CPACK_COMMAND "${CMake_TEST_EXTERNAL_CMAKE}/cpack")
      foreach(exe cmake ctest cpack)
        add_executable(${exe} IMPORTED)
        set_property(TARGET ${exe} PROPERTY IMPORTED_LOCATION ${CMake_TEST_EXTERNAL_CMAKE}/${exe})
      endforeach()
    else()
      set(CMAKE_CTEST_COMMAND "${CMake_BIN_DIR}/ctest")
      set(CMAKE_CMAKE_COMMAND "${CMake_BIN_DIR}/cmake")
      set(CMAKE_CPACK_COMMAND "${CMake_BIN_DIR}/cpack")
    endif()
  endif()

  # configure some files for testing
  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/Templates/CTestScript.cmake.in"
    "${CMAKE_CURRENT_BINARY_DIR}/CTestScript.cmake"
    @ONLY)
  configure_file(${CMake_SOURCE_DIR}/Tests/.NoDartCoverage
    ${CMake_BINARY_DIR}/Tests/.NoDartCoverage)
  configure_file(${CMake_SOURCE_DIR}/Tests/.NoDartCoverage
    ${CMake_BINARY_DIR}/Modules/.NoDartCoverage)
  configure_file(${CMake_SOURCE_DIR}/CTestCustom.cmake.in
    ${CMake_BINARY_DIR}/CTestCustom.cmake @ONLY)
  if(BUILD_TESTING AND DART_ROOT)
    configure_file(${CMake_SOURCE_DIR}/CMakeLogo.gif
      ${CMake_BINARY_DIR}/Testing/HTML/TestingResults/Icons/Logo.gif COPYONLY)
  endif()
  mark_as_advanced(DART_ROOT)
  mark_as_advanced(CURL_TESTING)
endmacro()


# Provide a way for Visual Studio Express users to turn OFF the new FOLDER
# organization feature. Default to ON for non-Express users. Express users must
# explicitly turn off this option to build CMake in the Express IDE...
#
option(CMAKE_USE_FOLDERS "Enable folder grouping of projects in IDEs." ON)
mark_as_advanced(CMAKE_USE_FOLDERS)


#-----------------------------------------------------------------------
# a macro that only sets the FOLDER target property if it's
# "appropriate"
#-----------------------------------------------------------------------
macro(CMAKE_SET_TARGET_FOLDER tgt folder)
  if(CMAKE_USE_FOLDERS)
    set_property(GLOBAL PROPERTY USE_FOLDERS ON)
    if(MSVC AND TARGET ${tgt})
      set_property(TARGET "${tgt}" PROPERTY FOLDER "${folder}")
    endif()
  else()
    set_property(GLOBAL PROPERTY USE_FOLDERS OFF)
  endif()
endmacro()


#-----------------------------------------------------------------------
# a macro to build the utilities used by CMake
# Simply to improve readability of the main script.
#-----------------------------------------------------------------------
macro (CMAKE_BUILD_UTILITIES)
  #---------------------------------------------------------------------
  # Create the kwsys library for CMake.
  set(KWSYS_NAMESPACE cmsys)
  set(KWSYS_USE_SystemTools 1)
  set(KWSYS_USE_Directory 1)
  set(KWSYS_USE_RegularExpression 1)
  set(KWSYS_USE_Base64 1)
  set(KWSYS_USE_MD5 1)
  set(KWSYS_USE_Process 1)
  set(KWSYS_USE_CommandLineArguments 1)
  set(KWSYS_USE_ConsoleBuf 1)
  set(KWSYS_HEADER_ROOT ${CMake_BINARY_DIR}/Source)
  set(KWSYS_INSTALL_DOC_DIR "${CMAKE_DOC_DIR}")
  add_subdirectory(Source/kwsys)
  set(kwsys_folder "Utilities/KWSys")
  CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE} "${kwsys_folder}")
  CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}_c "${kwsys_folder}")
  if(BUILD_TESTING)
    CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}TestDynload "${kwsys_folder}")
    CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}TestProcess "${kwsys_folder}")
    CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}TestsC "${kwsys_folder}")
    CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}TestsCxx "${kwsys_folder}")
    CMAKE_SET_TARGET_FOLDER(${KWSYS_NAMESPACE}TestSharedForward "${kwsys_folder}")
  endif()

  #---------------------------------------------------------------------
  # Setup third-party libraries.
  # Everything in the tree should be able to include files from the
  # Utilities directory.
  include_directories(
    ${CMake_BINARY_DIR}/Utilities
    ${CMake_SOURCE_DIR}/Utilities
    )

  # check for the use of system libraries versus builtin ones
  # (a macro defined in this file)
  CMAKE_HANDLE_SYSTEM_LIBRARIES()

  if(CMAKE_USE_SYSTEM_KWIML)
    find_package(KWIML 1.0)
    if(NOT KWIML_FOUND)
      message(FATAL_ERROR "CMAKE_USE_SYSTEM_KWIML is ON but KWIML is not found!")
    endif()
    set(CMake_KWIML_LIBRARIES kwiml::kwiml)
  else()
    set(CMake_KWIML_LIBRARIES "")
    if(BUILD_TESTING)
      set(KWIML_TEST_ENABLE 1)
    endif()
    add_subdirectory(Utilities/KWIML)
  endif()

  if(CMAKE_USE_SYSTEM_LIBRHASH)
    if(NOT CMAKE_VERSION VERSION_LESS 3.0)
      find_package(LibRHash)
    else()
      message(FATAL_ERROR "CMAKE_USE_SYSTEM_LIBRHASH requires CMake >= 3.0")
    endif()
    if(NOT LibRHash_FOUND)
      message(FATAL_ERROR
        "CMAKE_USE_SYSTEM_LIBRHASH is ON but LibRHash is not found!")
    endif()
    set(CMAKE_LIBRHASH_LIBRARIES LibRHash::LibRHash)
  else()
    set(CMAKE_LIBRHASH_LIBRARIES cmlibrhash)
    add_subdirectory(Utilities/cmlibrhash)
    CMAKE_SET_TARGET_FOLDER(cmlibrhash "Utilities/3rdParty")
  endif()

  #---------------------------------------------------------------------
  # Build zlib library for Curl, CMake, and CTest.
  set(CMAKE_ZLIB_HEADER "cm_zlib.h")
  if(CMAKE_USE_SYSTEM_ZLIB)
    find_package(ZLIB)
    if(NOT ZLIB_FOUND)
      message(FATAL_ERROR
        "CMAKE_USE_SYSTEM_ZLIB is ON but a zlib is not found!")
    endif()
    set(CMAKE_ZLIB_INCLUDES ${ZLIB_INCLUDE_DIR})
    set(CMAKE_ZLIB_LIBRARIES ${ZLIB_LIBRARIES})
  else()
    set(CMAKE_ZLIB_INCLUDES ${CMake_SOURCE_DIR}/Utilities)
    set(CMAKE_ZLIB_LIBRARIES cmzlib)
    add_subdirectory(Utilities/cmzlib)
    CMAKE_SET_TARGET_FOLDER(cmzlib "Utilities/3rdParty")
  endif()

  #---------------------------------------------------------------------
  # Build Curl library for CTest.
  if(CMAKE_USE_SYSTEM_CURL)
    find_package(CURL)
    if(NOT CURL_FOUND)
      message(FATAL_ERROR
        "CMAKE_USE_SYSTEM_CURL is ON but a curl is not found!")
    endif()
    set(CMAKE_CURL_INCLUDES ${CURL_INCLUDE_DIRS})
    set(CMAKE_CURL_LIBRARIES ${CURL_LIBRARIES})
  else()
    set(CURL_SPECIAL_ZLIB_H ${CMAKE_ZLIB_HEADER})
    set(CURL_SPECIAL_LIBZ_INCLUDES ${CMAKE_ZLIB_INCLUDES})
    set(CURL_SPECIAL_LIBZ ${CMAKE_ZLIB_LIBRARIES})
    add_definitions(-DCURL_STATICLIB)
    set(CMAKE_CURL_INCLUDES)
    set(CMAKE_CURL_LIBRARIES cmcurl)
    if(CMAKE_TESTS_CDASH_SERVER)
      set(CMAKE_CURL_TEST_URL "${CMAKE_TESTS_CDASH_SERVER}/user.php")
    endif()
    set(_CMAKE_USE_OPENSSL_DEFAULT OFF)
    if(NOT DEFINED CMAKE_USE_OPENSSL AND NOT WIN32 AND NOT APPLE
        AND CMAKE_SYSTEM_NAME MATCHES "(Linux|FreeBSD)")
      find_package(OpenSSL QUIET)
      if(OPENSSL_FOUND)
        set(_CMAKE_USE_OPENSSL_DEFAULT ON)
      endif()
    endif()
    option(CMAKE_USE_OPENSSL "Use OpenSSL." ${_CMAKE_USE_OPENSSL_DEFAULT})
    mark_as_advanced(CMAKE_USE_OPENSSL)
    if(CMAKE_USE_OPENSSL)
      set(CURL_CA_BUNDLE "" CACHE FILEPATH "Path to SSL CA Certificate Bundle")
      set(CURL_CA_PATH "" CACHE PATH "Path to SSL CA Certificate Directory")
      mark_as_advanced(CURL_CA_BUNDLE CURL_CA_PATH)
    endif()
    add_subdirectory(Utilities/cmcurl)
    CMAKE_SET_TARGET_FOLDER(cmcurl "Utilities/3rdParty")
    CMAKE_SET_TARGET_FOLDER(LIBCURL "Utilities/3rdParty")
  endif()

  #---------------------------------------------------------------------
  # Build Compress library for CTest.
  set(CMAKE_COMPRESS_INCLUDES
    "${CMAKE_CURRENT_BINARY_DIR}/Utilities/cmcompress")
  set(CMAKE_COMPRESS_LIBRARIES "cmcompress")
  add_subdirectory(Utilities/cmcompress)
  CMAKE_SET_TARGET_FOLDER(cmcompress "Utilities/3rdParty")

  #---------------------------------------------------------------------
  # Build expat library for CMake, CTest, and libarchive.
  if(CMAKE_USE_SYSTEM_EXPAT)
    find_package(EXPAT)
    if(NOT EXPAT_FOUND)
      message(FATAL_ERROR
        "CMAKE_USE_SYSTEM_EXPAT is ON but a expat is not found!")
    endif()
    set(CMAKE_EXPAT_INCLUDES ${EXPAT_INCLUDE_DIRS})
    set(CMAKE_EXPAT_LIBRARIES ${EXPAT_LIBRARIES})
  else()
    set(CMAKE_EXPAT_INCLUDES)
    set(CMAKE_EXPAT_LIBRARIES cmexpat)
    add_subdirectory(Utilities/cmexpat)
    CMAKE_SET_TARGET_FOLDER(cmexpat "Utilities/3rdParty")
  endif()

  #---------------------------------------------------------------------
  # Build or use system libbz2 for libarchive.
  if(NOT CMAKE_USE_SYSTEM_LIBARCHIVE)
    if(CMAKE_USE_SYSTEM_BZIP2)
      find_package(BZip2)
    else()
      set(BZIP2_INCLUDE_DIR
        "${CMAKE_CURRENT_SOURCE_DIR}/Utilities/cmbzip2")
      set(BZIP2_LIBRARIES cmbzip2)
      add_subdirectory(Utilities/cmbzip2)
      CMAKE_SET_TARGET_FOLDER(cmbzip2 "Utilities/3rdParty")
    endif()
  endif()

  #---------------------------------------------------------------------
  # Build or use system liblzma for libarchive.
  if(NOT CMAKE_USE_SYSTEM_LIBARCHIVE)
    if(CMAKE_USE_SYSTEM_LIBLZMA)
      find_package(LibLZMA)
      if(NOT LIBLZMA_FOUND)
        message(FATAL_ERROR "CMAKE_USE_SYSTEM_LIBLZMA is ON but LibLZMA is not found!")
      endif()
    else()
      add_subdirectory(Utilities/cmliblzma)
      CMAKE_SET_TARGET_FOLDER(cmliblzma "Utilities/3rdParty")
      set(LIBLZMA_HAS_AUTO_DECODER 1)
      set(LIBLZMA_HAS_EASY_ENCODER 1)
      set(LIBLZMA_HAS_LZMA_PRESET 1)
      set(LIBLZMA_INCLUDE_DIR
        "${CMAKE_CURRENT_SOURCE_DIR}/Utilities/cmliblzma/liblzma/api")
      set(LIBLZMA_LIBRARY cmliblzma)
    endif()
  endif()

  #---------------------------------------------------------------------
  # Build or use system libarchive for CMake and CTest.
  if(CMAKE_USE_SYSTEM_LIBARCHIVE)
    find_package(LibArchive 3.0.0)
    if(NOT LibArchive_FOUND)
      message(FATAL_ERROR "CMAKE_USE_SYSTEM_LIBARCHIVE is ON but LibArchive is not found!")
    endif()
    set(CMAKE_TAR_INCLUDES ${LibArchive_INCLUDE_DIRS})
    set(CMAKE_TAR_LIBRARIES ${LibArchive_LIBRARIES})
  else()
    set(EXPAT_INCLUDE_DIR ${CMAKE_EXPAT_INCLUDES})
    set(EXPAT_LIBRARY ${CMAKE_EXPAT_LIBRARIES})
    set(ZLIB_INCLUDE_DIR ${CMAKE_ZLIB_INCLUDES})
    set(ZLIB_LIBRARY ${CMAKE_ZLIB_LIBRARIES})
    add_definitions(-DLIBARCHIVE_STATIC)
    set(ENABLE_NETTLE OFF CACHE INTERNAL "Enable use of Nettle")
    set(ENABLE_OPENSSL ${CMAKE_USE_OPENSSL} CACHE INTERNAL "Enable use of OpenSSL")
    set(ENABLE_LZMA ON CACHE INTERNAL "Enable the use of the system LZMA library if found")
    set(ENABLE_LZO OFF CACHE INTERNAL "Enable the use of the system LZO library if found")
    set(ENABLE_ZLIB ON CACHE INTERNAL "Enable the use of the system ZLIB library if found")
    set(ENABLE_BZip2 ON CACHE INTERNAL "Enable the use of the system BZip2 library if found")
    set(ENABLE_LIBXML2 OFF CACHE INTERNAL "Enable the use of the system libxml2 library if found")
    set(ENABLE_EXPAT ON CACHE INTERNAL "Enable the use of the system EXPAT library if found")
    set(ENABLE_PCREPOSIX OFF CACHE INTERNAL "Enable the use of the system PCREPOSIX library if found")
    set(ENABLE_LibGCC OFF CACHE INTERNAL "Enable the use of the system LibGCC library if found")
    set(ENABLE_XATTR OFF CACHE INTERNAL "Enable extended attribute support")
    set(ENABLE_ACL OFF CACHE INTERNAL "Enable ACL support")
    set(ENABLE_ICONV OFF CACHE INTERNAL "Enable iconv support")
    set(ENABLE_CNG OFF CACHE INTERNAL "Enable the use of CNG(Crypto Next Generation)")
    add_subdirectory(Utilities/cmlibarchive)
    CMAKE_SET_TARGET_FOLDER(cmlibarchive "Utilities/3rdParty")
    set(CMAKE_TAR_LIBRARIES cmlibarchive ${BZIP2_LIBRARIES})
  endif()

  #---------------------------------------------------------------------
  # Build jsoncpp library.
  if(CMAKE_USE_SYSTEM_JSONCPP)
    if(NOT CMAKE_VERSION VERSION_LESS 3.0)
      find_package(JsonCpp)
    else()
      message(FATAL_ERROR "CMAKE_USE_SYSTEM_JSONCPP requires CMake >= 3.0")
    endif()
    if(NOT JsonCpp_FOUND)
      message(FATAL_ERROR
        "CMAKE_USE_SYSTEM_JSONCPP is ON but a JsonCpp is not found!")
    endif()
    set(CMAKE_JSONCPP_LIBRARIES JsonCpp::JsonCpp)
  else()
    set(CMAKE_JSONCPP_LIBRARIES cmjsoncpp)
    add_subdirectory(Utilities/cmjsoncpp)
    CMAKE_SET_TARGET_FOLDER(cmjsoncpp "Utilities/3rdParty")
  endif()

  #---------------------------------------------------------------------
  # Build libuv library.
  if(NOT DEFINED CMAKE_USE_LIBUV)
    set(CMAKE_USE_LIBUV 1)
    if(APPLE)
      include(CheckCSourceCompiles)
      check_c_source_compiles("
#include <CoreServices/CoreServices.h>
#include <AvailabilityMacros.h>
#ifndef MAC_OS_X_VERSION_10_5
#error \"MAC_OS_X_VERSION_10_5 is not defined\"
#endif
int main(void) { return 0; }
" HAVE_CoreServices_OS_X_10_5)
      if(NOT HAVE_CoreServices_OS_X_10_5)
        set(CMAKE_USE_LIBUV 0)
      endif()
    elseif(CYGWIN)
      # libuv does not support Cygwin
      set(CMAKE_USE_LIBUV 0)
    elseif(CMAKE_SYSTEM_NAME STREQUAL "HP-UX")
      # Disable until it can be ported.
      set(CMAKE_USE_LIBUV 0)
    endif()
  endif()
  if(CMAKE_USE_LIBUV)
    if(CMAKE_USE_SYSTEM_LIBUV)
      if(NOT CMAKE_VERSION VERSION_LESS 3.0)
        find_package(LibUV 1.0.0)
      else()
        message(FATAL_ERROR "CMAKE_USE_SYSTEM_LIBUV requires CMake >= 3.0")
      endif()
      if(NOT LIBUV_FOUND)
        message(FATAL_ERROR
          "CMAKE_USE_SYSTEM_LIBUV is ON but a libuv is not found!")
      endif()
      set(CMAKE_LIBUV_LIBRARIES LibUV::LibUV)
    else()
      set(CMAKE_LIBUV_LIBRARIES cmlibuv)
      add_subdirectory(Utilities/cmlibuv)
      CMAKE_SET_TARGET_FOLDER(cmlibuv "Utilities/3rdParty")
    endif()
  else()
    set(CMAKE_LIBUV_LIBRARIES)
  endif()

  #---------------------------------------------------------------------
  # Build XMLRPC library for CMake and CTest.
  if(CTEST_USE_XMLRPC)
    find_package(XMLRPC QUIET REQUIRED libwww-client)
    if(NOT XMLRPC_FOUND)
      message(FATAL_ERROR
        "CTEST_USE_XMLRPC is ON but xmlrpc is not found!")
    endif()
    set(CMAKE_XMLRPC_INCLUDES ${XMLRPC_INCLUDE_DIRS})
    set(CMAKE_XMLRPC_LIBRARIES ${XMLRPC_LIBRARIES})
  endif()

  #---------------------------------------------------------------------
  # Use curses?
  if (UNIX)
    # there is a bug in the Syllable libraries which makes linking ccmake fail, Alex
    if(NOT CMAKE_SYSTEM_NAME MATCHES syllable)
      set(CURSES_NEED_NCURSES TRUE)
      find_package(Curses QUIET)
      if (CURSES_LIBRARY)
        option(BUILD_CursesDialog "Build the CMake Curses Dialog ccmake" ON)
      else ()
        message("Curses libraries were not found. Curses GUI for CMake will not be built.")
        set(BUILD_CursesDialog 0)
      endif ()
    else()
      set(BUILD_CursesDialog 0)
    endif()
  else ()
    set(BUILD_CursesDialog 0)
  endif ()
  if(BUILD_CursesDialog)
    if(NOT CMAKE_USE_SYSTEM_FORM)
      add_subdirectory(Source/CursesDialog/form)
    elseif(NOT CURSES_FORM_LIBRARY)
      message( FATAL_ERROR "CMAKE_USE_SYSTEM_FORM in ON but CURSES_FORM_LIBRARY is not set!" )
    endif()
  endif()
endmacro ()

#-----------------------------------------------------------------------
if(NOT CMake_TEST_EXTERNAL_CMAKE)
  if(CMAKE_CXX_PLATFORM_ID MATCHES "OpenBSD")
    execute_process(COMMAND ${CMAKE_CXX_COMPILER}
      ${CMAKE_CXX_COMPILER_ARG1} -dumpversion
      OUTPUT_VARIABLE _GXX_VERSION
    )
    string(REGEX REPLACE "([0-9])\\.([0-9])(\\.[0-9])?" "\\1\\2"
      _GXX_VERSION_SHORT ${_GXX_VERSION})
    if(_GXX_VERSION_SHORT EQUAL 33)
      message(FATAL_ERROR
        "GXX 3.3 on OpenBSD is known to cause CPack to Crash.\n"
        "Please use GXX 4.2 or greater to build CMake on OpenBSD\n"
        "${CMAKE_CXX_COMPILER} version is: ${_GXX_VERSION}")
    endif()
  endif()
endif()

#-----------------------------------------------------------------------
# The main section of the CMakeLists file
#
#-----------------------------------------------------------------------
# Compute CMake_VERSION, etc.
include(Source/CMakeVersionCompute.cmake)

# Include the standard Dart testing module
enable_testing()
include (${CMAKE_ROOT}/Modules/Dart.cmake)

# Set up test-time configuration.
set_directory_properties(PROPERTIES
  TEST_INCLUDE_FILE "${CMake_BINARY_DIR}/Tests/EnforceConfig.cmake")

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  # where to write the resulting executables and libraries
  set(BUILD_SHARED_LIBS OFF)
  set(EXECUTABLE_OUTPUT_PATH "" CACHE INTERNAL "No configurable exe dir.")
  set(LIBRARY_OUTPUT_PATH "" CACHE INTERNAL
    "Where to put the libraries for CMake")

  # The CMake executables usually do not need any rpath to run in the build or
  # install tree.
  set(CMAKE_SKIP_RPATH ON CACHE INTERNAL "CMake does not need RPATHs.")

  # Load install destinations.
  include(Source/CMakeInstallDestinations.cmake)

  if(BUILD_TESTING)
    include(${CMake_SOURCE_DIR}/Tests/CMakeInstall.cmake)
  endif()

  # include special compile flags for some compilers
  include(CompileFlags.cmake)

  # no clue why we are testing for this here
  include(CheckSymbolExists)
  CHECK_SYMBOL_EXISTS(unsetenv "stdlib.h" HAVE_UNSETENV)
  CHECK_SYMBOL_EXISTS(environ "stdlib.h" HAVE_ENVIRON_NOT_REQUIRE_PROTOTYPE)
endif()

# CMAKE_TESTS_CDASH_SERVER: CDash server used by CMake/Tests.
#
# If not defined or "", this variable defaults to the server at
# "http://open.cdash.org".
#
# If set explicitly to "NOTFOUND", curl tests and ctest tests that use
# the network are skipped.
#
# If set to something starting with "http://localhost/", the CDash is
# expected to be an instance of CDash used for CDash testing, pointing
# to a cdash4simpletest database. In these cases, the CDash dashboards
# should be run first.
#
if("x${CMAKE_TESTS_CDASH_SERVER}" STREQUAL "x")
  set(CMAKE_TESTS_CDASH_SERVER "http://open.cdash.org")
endif()

if(CMake_TEST_EXTERNAL_CMAKE)
  set(KWIML_TEST_ENABLE 1)
  add_subdirectory(Utilities/KWIML)
endif()

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  # build the utilities (a macro defined in this file)
  CMAKE_BUILD_UTILITIES()

  # On NetBSD ncurses is required, since curses doesn't have the wsyncup()
  # function. ncurses is installed via pkgsrc, so the library is in /usr/pkg/lib,
  # which isn't in the default linker search path. So without RPATH ccmake
  # doesn't run and the build doesn't succeed since ccmake is executed for
  # generating the documentation.
  if(BUILD_CursesDialog)
    get_filename_component(_CURSES_DIR "${CURSES_LIBRARY}" PATH)
    set(CURSES_NEED_RPATH FALSE)
    if(NOT "${_CURSES_DIR}" STREQUAL "/lib" AND NOT "${_CURSES_DIR}" STREQUAL "/usr/lib" AND NOT "${_CURSES_DIR}" STREQUAL "/lib64" AND NOT "${_CURSES_DIR}" STREQUAL "/usr/lib64")
      set(CURSES_NEED_RPATH TRUE)
    endif()
  endif()

  if(BUILD_QtDialog)
    if(APPLE)
      set(CMAKE_BUNDLE_VERSION
        "${CMake_VERSION_MAJOR}.${CMake_VERSION_MINOR}.${CMake_VERSION_PATCH}")
      set(CMAKE_BUNDLE_LOCATION "${CMAKE_INSTALL_PREFIX}")
      # make sure CMAKE_INSTALL_PREFIX ends in /
      if(NOT CMAKE_INSTALL_PREFIX MATCHES "/$")
        set(CMAKE_INSTALL_PREFIX "${CMAKE_INSTALL_PREFIX}/")
      endif()
      set(CMAKE_INSTALL_PREFIX
        "${CMAKE_INSTALL_PREFIX}CMake.app/Contents")
    endif()

    set(QT_NEED_RPATH FALSE)
    if(NOT "${QT_LIBRARY_DIR}" STREQUAL "/lib" AND NOT "${QT_LIBRARY_DIR}" STREQUAL "/usr/lib" AND NOT "${QT_LIBRARY_DIR}" STREQUAL "/lib64" AND NOT "${QT_LIBRARY_DIR}" STREQUAL "/usr/lib64")
      set(QT_NEED_RPATH TRUE)
    endif()
  endif()


  # The same might be true on other systems for other libraries.
  # Then only enable RPATH if we have are building at least with cmake 2.4,
  # since this one has much better RPATH features than cmake 2.2.
  # The executables are then built with the RPATH for the libraries outside
  # the build tree, which is both the build and the install RPATH.
  if (UNIX)
    if(   CMAKE_USE_SYSTEM_CURL   OR  CMAKE_USE_SYSTEM_ZLIB
          OR  CMAKE_USE_SYSTEM_EXPAT  OR  CTEST_USE_XMLRPC  OR  CURSES_NEED_RPATH  OR  QT_NEED_RPATH)
      set(CMAKE_SKIP_RPATH OFF CACHE INTERNAL "CMake built with RPATH.")
      set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
      set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
    endif()
  endif ()


  # add the uninstall support
  configure_file(
    "${CMAKE_CURRENT_SOURCE_DIR}/cmake_uninstall.cmake.in"
    "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake"
    @ONLY)
  add_custom_target(uninstall
    "${CMAKE_COMMAND}" -P "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake")

  include (CMakeCPack.cmake)

endif()

# setup some Testing support (a macro defined in this file)
CMAKE_SETUP_TESTING()

# Check whether to build server mode or not:
if(NOT CMake_TEST_EXTERNAL_CMAKE)
  if(NOT DEFINED CMake_ENABLE_SERVER_MODE)
    list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_auto_type CMake_HAVE_CXX_AUTO_TYPE)
    list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_range_for CMake_HAVE_CXX_RANGE_FOR)
    if(CMAKE_USE_LIBUV
        AND CMake_HAVE_CXX_AUTO_TYPE
        AND CMake_HAVE_CXX_MAKE_UNIQUE
        AND CMake_HAVE_CXX_RANGE_FOR
        )
      set(CMake_ENABLE_SERVER_MODE 1)
    else()
      set(CMake_ENABLE_SERVER_MODE 0)
    endif()
  endif()
  if(CMake_ENABLE_SERVER_MODE AND NOT CMAKE_USE_LIBUV)
    message(FATAL_ERROR "The server mode requires libuv!")
  endif()
else()
  set(CMake_ENABLE_SERVER_MODE 0)
endif()
if(NOT DEFINED CMake_TEST_SERVER_MODE)
  set(CMake_TEST_SERVER_MODE ${CMake_ENABLE_SERVER_MODE})
endif()

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  if(NOT CMake_VERSION_IS_RELEASE)
    if(CMAKE_C_COMPILER_ID STREQUAL "GNU" AND
        NOT "${CMAKE_C_COMPILER_VERSION}" VERSION_LESS 4.2)
      set(C_FLAGS_LIST -Wcast-align -Werror-implicit-function-declaration -Wchar-subscripts
                       -Wall -W -Wpointer-arith -Wwrite-strings -Wformat-security
                       -Wmissing-format-attribute -fno-common -Wundef
      )
      set(CXX_FLAGS_LIST -Wnon-virtual-dtor -Wcast-align -Wchar-subscripts -Wall -W
                         -Wshadow -Wpointer-arith -Wformat-security -Wundef
      )

      foreach(FLAG_LANG  C CXX)
        foreach(FLAG ${${FLAG_LANG}_FLAGS_LIST})
          if(NOT " ${CMAKE_${FLAG_LANG}_FLAGS} " MATCHES " ${FLAG} ")
            set(CMAKE_${FLAG_LANG}_FLAGS "${CMAKE_${FLAG_LANG}_FLAGS} ${FLAG}")
          endif()
        endforeach()
      endforeach()

      unset(C_FLAGS_LIST)
      unset(CXX_FLAGS_LIST)
    endif()
  endif()

  # build the remaining subdirectories
  add_subdirectory(Source)
  add_subdirectory(Utilities)
endif()

add_subdirectory(Tests)

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  if(BUILD_TESTING)
    CMAKE_SET_TARGET_FOLDER(CMakeLibTests "Tests")
  endif()
  if(TARGET documentation)
    CMAKE_SET_TARGET_FOLDER(documentation "Documentation")
  endif()
endif()

# add a test
add_test(SystemInformationNew "${CMAKE_CMAKE_COMMAND}"
  --system-information  -G "${CMAKE_GENERATOR}" )

if(NOT CMake_TEST_EXTERNAL_CMAKE)
  # Install license file as it requires.
  install(FILES Copyright.txt DESTINATION ${CMAKE_DOC_DIR})

  # Install script directories.
  install(
    DIRECTORY Help Modules Templates
    DESTINATION ${CMAKE_DATA_DIR}
    FILE_PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
    DIRECTORY_PERMISSIONS OWNER_READ OWNER_EXECUTE OWNER_WRITE
                          GROUP_READ GROUP_EXECUTE
                          WORLD_READ WORLD_EXECUTE
    PATTERN "*.sh*" PERMISSIONS OWNER_READ OWNER_EXECUTE OWNER_WRITE
                                GROUP_READ GROUP_EXECUTE
                                WORLD_READ WORLD_EXECUTE
    REGEX "Help/dev($|/)" EXCLUDE
    )

  # Install auxiliary files integrating with other tools.
  add_subdirectory(Auxiliary)
endif()