# Distributed under the OSI-approved BSD 3-Clause License. See accompanying | |
# file Copyright.txt or https://cmake.org/licensing for details. | |
#.rst: | |
# CheckStructHasMember | |
# -------------------- | |
# | |
# Check if the given struct or class has the specified member variable | |
# | |
# :: | |
# | |
# CHECK_STRUCT_HAS_MEMBER(<struct> <member> <header> <variable> | |
# [LANGUAGE <language>]) | |
# | |
# :: | |
# | |
# <struct> - the name of the struct or class you are interested in | |
# <member> - the member which existence you want to check | |
# <header> - the header(s) where the prototype should be declared | |
# <variable> - variable to store the result | |
# <language> - the compiler to use (C or CXX) | |
# | |
# | |
# | |
# The following variables may be set before calling this macro to modify | |
# the way the check is run: | |
# | |
# :: | |
# | |
# CMAKE_REQUIRED_FLAGS = string of compile command line flags | |
# CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar) | |
# CMAKE_REQUIRED_INCLUDES = list of include directories | |
# CMAKE_REQUIRED_LIBRARIES = list of libraries to link | |
# CMAKE_REQUIRED_QUIET = execute quietly without messages | |
# | |
# | |
# | |
# Example: CHECK_STRUCT_HAS_MEMBER("struct timeval" tv_sec sys/select.h | |
# HAVE_TIMEVAL_TV_SEC LANGUAGE C) | |
include(CheckCSourceCompiles) | |
include(CheckCXXSourceCompiles) | |
macro (CHECK_STRUCT_HAS_MEMBER _STRUCT _MEMBER _HEADER _RESULT) | |
set(_INCLUDE_FILES) | |
foreach (it ${_HEADER}) | |
string(APPEND _INCLUDE_FILES "#include <${it}>\n") | |
endforeach () | |
if("x${ARGN}" STREQUAL "x") | |
set(_lang C) | |
elseif("x${ARGN}" MATCHES "^xLANGUAGE;([a-zA-Z]+)$") | |
set(_lang "${CMAKE_MATCH_1}") | |
else() | |
message(FATAL_ERROR "Unknown arguments:\n ${ARGN}\n") | |
endif() | |
set(_CHECK_STRUCT_MEMBER_SOURCE_CODE " | |
${_INCLUDE_FILES} | |
int main() | |
{ | |
(void)sizeof(((${_STRUCT} *)0)->${_MEMBER}); | |
return 0; | |
} | |
") | |
if("${_lang}" STREQUAL "C") | |
CHECK_C_SOURCE_COMPILES("${_CHECK_STRUCT_MEMBER_SOURCE_CODE}" ${_RESULT}) | |
elseif("${_lang}" STREQUAL "CXX") | |
CHECK_CXX_SOURCE_COMPILES("${_CHECK_STRUCT_MEMBER_SOURCE_CODE}" ${_RESULT}) | |
else() | |
message(FATAL_ERROR "Unknown language:\n ${_lang}\nSupported languages: C, CXX.\n") | |
endif() | |
endmacro () |