qt-build-tools/6.5.1/_tools/cmake/share/cmake-3.27/Modules/TestBigEndian.cmake
2023-11-01 01:44:24 +01:00

133 lines
4.7 KiB
CMake

# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#[=======================================================================[.rst:
TestBigEndian
-------------
.. deprecated:: 3.20
Supserseded by the :variable:`CMAKE_<LANG>_BYTE_ORDER` variable.
Check if the target architecture is big endian or little endian.
.. command:: test_big_endian
.. code-block:: cmake
test_big_endian(<var>)
Stores in variable ``<var>`` either 1 or 0 indicating whether the
target architecture is big or little endian.
#]=======================================================================]
include_guard()
include(CheckTypeSize)
function(TEST_BIG_ENDIAN VARIABLE)
if(";${CMAKE_C_BYTE_ORDER};${CMAKE_CXX_BYTE_ORDER};${CMAKE_CUDA_BYTE_ORDER};${CMAKE_OBJC_BYTE_ORDER};${CMAKE_OBJCXX_BYTE_ORDER};" MATCHES ";(BIG_ENDIAN|LITTLE_ENDIAN);")
set(order "${CMAKE_MATCH_1}")
if(order STREQUAL "BIG_ENDIAN")
set("${VARIABLE}" 1 PARENT_SCOPE)
else()
set("${VARIABLE}" 0 PARENT_SCOPE)
endif()
else()
__TEST_BIG_ENDIAN_LEGACY_IMPL(is_big)
set("${VARIABLE}" "${is_big}" PARENT_SCOPE)
endif()
endfunction()
macro(__TEST_BIG_ENDIAN_LEGACY_IMPL VARIABLE)
if(NOT DEFINED HAVE_${VARIABLE})
message(CHECK_START "Check if the system is big endian")
message(CHECK_START "Searching 16 bit integer")
if(CMAKE_C_COMPILER_LOADED)
set(_test_language "C")
elseif(CMAKE_CXX_COMPILER_LOADED)
set(_test_language "CXX")
else()
message(FATAL_ERROR "TEST_BIG_ENDIAN needs either C or CXX language enabled")
endif()
CHECK_TYPE_SIZE("unsigned short" CMAKE_SIZEOF_UNSIGNED_SHORT LANGUAGE ${_test_language})
if(CMAKE_SIZEOF_UNSIGNED_SHORT EQUAL 2)
message(CHECK_PASS "Using unsigned short")
set(CMAKE_16BIT_TYPE "unsigned short")
else()
CHECK_TYPE_SIZE("unsigned int" CMAKE_SIZEOF_UNSIGNED_INT LANGUAGE ${_test_language})
if(CMAKE_SIZEOF_UNSIGNED_INT)
message(CHECK_PASS "Using unsigned int")
set(CMAKE_16BIT_TYPE "unsigned int")
else()
CHECK_TYPE_SIZE("unsigned long" CMAKE_SIZEOF_UNSIGNED_LONG LANGUAGE ${_test_language})
if(CMAKE_SIZEOF_UNSIGNED_LONG)
message(CHECK_PASS "Using unsigned long")
set(CMAKE_16BIT_TYPE "unsigned long")
else()
message(FATAL_ERROR "no suitable type found")
endif()
endif()
endif()
if(_test_language STREQUAL "CXX")
set(_test_file TestEndianess.cpp)
else()
set(_test_file TestEndianess.c)
endif()
file(READ "${CMAKE_ROOT}/Modules/TestEndianess.c.in" TEST_ENDIANESS_FILE_CONTENT)
string(CONFIGURE "${TEST_ENDIANESS_FILE_CONTENT}" TEST_ENDIANESS_FILE_CONTENT @ONLY)
try_compile(HAVE_${VARIABLE}
SOURCE_FROM_VAR "${_test_file}" TEST_ENDIANESS_FILE_CONTENT
COPY_FILE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestEndianess.bin" )
if(HAVE_${VARIABLE})
file(STRINGS "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestEndianess.bin"
CMAKE_TEST_ENDIANESS_STRINGS_LE LIMIT_COUNT 1 REGEX "THIS IS LITTLE ENDIAN")
file(STRINGS "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestEndianess.bin"
CMAKE_TEST_ENDIANESS_STRINGS_BE LIMIT_COUNT 1 REGEX "THIS IS BIG ENDIAN")
# on mac, if there are universal binaries built both will be true
# return the result depending on the machine on which cmake runs
if(CMAKE_TEST_ENDIANESS_STRINGS_BE AND CMAKE_TEST_ENDIANESS_STRINGS_LE)
if(CMAKE_SYSTEM_PROCESSOR MATCHES powerpc)
set(CMAKE_TEST_ENDIANESS_STRINGS_BE TRUE)
set(CMAKE_TEST_ENDIANESS_STRINGS_LE FALSE)
else()
set(CMAKE_TEST_ENDIANESS_STRINGS_BE FALSE)
set(CMAKE_TEST_ENDIANESS_STRINGS_LE TRUE)
endif()
message(STATUS "TEST_BIG_ENDIAN found different results, consider setting CMAKE_OSX_ARCHITECTURES or CMAKE_TRY_COMPILE_OSX_ARCHITECTURES to one or no architecture !")
endif()
if(CMAKE_TEST_ENDIANESS_STRINGS_LE)
set(${VARIABLE} 0 CACHE INTERNAL "Result of TEST_BIG_ENDIAN" FORCE)
message(CHECK_PASS "little endian")
endif()
if(CMAKE_TEST_ENDIANESS_STRINGS_BE)
set(${VARIABLE} 1 CACHE INTERNAL "Result of TEST_BIG_ENDIAN" FORCE)
message(CHECK_PASS "big endian")
endif()
if(NOT CMAKE_TEST_ENDIANESS_STRINGS_BE AND NOT CMAKE_TEST_ENDIANESS_STRINGS_LE)
message(CHECK_FAIL "TEST_BIG_ENDIAN found no result!")
message(SEND_ERROR "TEST_BIG_ENDIAN found no result!")
endif()
else()
message(CHECK_FAIL "failed")
set(${VARIABLE})
endif()
endif()
endmacro()