Modules/CheckLibraryExists.cmake

   1 # - Check if the function exists.
   2 # CHECK_LIBRARY_EXISTS (LIBRARY FUNCTION LOCATION VARIABLE)
   3 #
   4 #  LIBRARY  - the name of the library you are looking for
   5 #  FUNCTION - the name of the function
   6 #  LOCATION - location where the library should be found
   7 #  VARIABLE - variable to store the result
   8 #
   9 # The following variables may be set before calling this macro to
  10 # modify the way the check is run:
  11 #
  12 #  CMAKE_REQUIRED_FLAGS = string of compile command line flags
  13 #  CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
  14 #  CMAKE_REQUIRED_LIBRARIES = list of libraries to link
  15
  16 MACRO(CHECK_LIBRARY_EXISTS LIBRARY FUNCTION LOCATION VARIABLE)
  17   IF("${VARIABLE}" MATCHES "^${VARIABLE}$")
  18     SET(MACRO_CHECK_LIBRARY_EXISTS_DEFINITION
  19       "-DCHECK_FUNCTION_EXISTS=${FUNCTION} ${CMAKE_REQUIRED_FLAGS}")
  20     MESSAGE(STATUS "Looking for ${FUNCTION} in ${LIBRARY}")
  21     SET(CHECK_LIBRARY_EXISTS_LIBRARIES ${LIBRARY})
  22     IF(CMAKE_REQUIRED_LIBRARIES)
  23       SET(CHECK_LIBRARY_EXISTS_LIBRARIES
  24         ${CHECK_LIBRARY_EXISTS_LIBRARIES} ${CMAKE_REQUIRED_LIBRARIES})
  25     ENDIF(CMAKE_REQUIRED_LIBRARIES)
  26     TRY_COMPILE(${VARIABLE}
  27       ${CMAKE_BINARY_DIR}
  28       ${CMAKE_ROOT}/Modules/CheckFunctionExists.c
  29       COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
  30       CMAKE_FLAGS
  31       -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_LIBRARY_EXISTS_DEFINITION}
  32       -DLINK_DIRECTORIES:STRING=${LOCATION}
  33       "-DLINK_LIBRARIES:STRING=${CHECK_LIBRARY_EXISTS_LIBRARIES}"
  34       OUTPUT_VARIABLE OUTPUT)
  35
  36     IF(${VARIABLE})
  37       MESSAGE(STATUS "Looking for ${FUNCTION} in ${LIBRARY} - found")
  38       SET(${VARIABLE} 1 CACHE INTERNAL "Have library ${LIBRARY}")
  39       FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
  40         "Determining if the function ${FUNCTION} exists in the ${LIBRARY} "
  41         "passed with the following output:\n"
  42         "${OUTPUT}\n\n")
  43     ELSE(${VARIABLE})
  44       MESSAGE(STATUS "Looking for ${FUNCTION} in ${LIBRARY} - not found")
  45       SET(${VARIABLE} "" CACHE INTERNAL "Have library ${LIBRARY}")
  46       FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
  47         "Determining if the function ${FUNCTION} exists in the ${LIBRARY} "
  48         "failed with the following output:\n"
  49         "${OUTPUT}\n\n")
  50     ENDIF(${VARIABLE})
  51   ENDIF("${VARIABLE}" MATCHES "^${VARIABLE}$")
  52 ENDMACRO(CHECK_LIBRARY_EXISTS)