CMake/Modules/CheckSymbolExists.cmake

49 lines
2.0 KiB
CMake

#
# Check if the symbol exists in include files
#
# CHECK_SYMBOL_EXISTS - macro which checks the symbol exists in include files.
# SYMBOL - symbol
# FILES - include files to check
# VARIABLE - variable to return result
#
MACRO(CHECK_SYMBOL_EXISTS SYMBOL FILES VARIABLE)
IF("${VARIABLE}" MATCHES "^${VARIABLE}$")
SET(CHECK_SYMBOL_EXISTS_CONTENT "/* */\n")
SET(MACRO_CHECK_SYMBOL_EXISTS_FLAGS ${CMAKE_REQUIRED_FLAGS})
STRING(ASCII 35 POUND)
STRING(ASCII 40 OPEN_PARENT)
STRING(ASCII 41 CLOSE_PARENT)
SET(PARENTS "${OPEN_PARENT}${CLOSE_PARENT}")
FOREACH(FILE ${FILES})
SET(CHECK_SYMBOL_EXISTS_CONTENT
"${CHECK_SYMBOL_EXISTS_CONTENT}${POUND}include <${FILE}>\n")
ENDFOREACH(FILE)
SET(CHECK_SYMBOL_EXISTS_CONTENT
"${CHECK_SYMBOL_EXISTS_CONTENT}\n\nint main${PARENTS}{"
"\n${POUND}ifndef ${SYMBOL}\nchar ${OPEN_PARENT}*f${CLOSE_PARENT} ${PARENTS} = ${SYMBOL};\n${POUND}endif\nreturn 0;\n}\n")
WRITE_FILE(${CMAKE_BINARY_DIR}/CMakeTmp/CheckSymbolExists.c
"${CHECK_SYMBOL_EXISTS_CONTENT}")
MESSAGE(STATUS "Looking for ${SYMBOL} in ${FILES}")
TRY_COMPILE(${VARIABLE}
${CMAKE_BINARY_DIR}
${CMAKE_BINARY_DIR}/CMakeTmp/CheckSymbolExists.c
CMAKE_FLAGS
-DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_SYMBOL_EXISTS_FLAGS}
OUTPUT_VARIABLE OUTPUT)
IF(${VARIABLE})
MESSAGE(STATUS "Looking for ${SYMBOL} in ${FILES} - found")
SET(${VARIABLE} 1 CACHE INTERNAL "Have symbol ${SYMBOL}")
ELSE(${VARIABLE})
MESSAGE(STATUS "Looking for ${SYMBOL} in ${FILES} - not found.")
SET(${VARIABLE} "" CACHE INTERNAL "Have symbol ${SYMBOL}")
WRITE_FILE(${CMAKE_BINARY_DIR}/CMakeError.log
"Determining if the ${SYMBOL} "
"exist failed with the following output:\n"
"${OUTPUT}\nFile ${CMAKE_BINARY_DIR}/CMakeTmp/CheckSymbolExists.c:\n"
"${CHECK_SYMBOL_EXISTS_CONTENT}" APPEND)
ENDIF(${VARIABLE})
ENDIF("${VARIABLE}" MATCHES "^${VARIABLE}$")
ENDMACRO(CHECK_SYMBOL_EXISTS)