Modules/CMakePushCheckState.cmake

   1 # This module defines two macros:
   2 # CMAKE_PUSH_CHECK_STATE()
   3 # and
   4 # CMAKE_POP_CHECK_STATE()
   5 # These two macros can be used to save and restore the state of the variables
   6 # CMAKE_REQUIRED_FLAGS, CMAKE_REQUIRED_DEFINITIONS, CMAKE_REQUIRED_LIBRARIES
   7 # and CMAKE_REQUIRED_INCLUDES used by the various Check-files coming with CMake,
   8 # like e.g. check_function_exists() etc.
   9 # The variable contents are pushed on a stack, pushing multiple times is supported.
  10 # This is useful e.g. when executing such tests in a Find-module, where they have to be set,
  11 # but after the Find-module has been executed they should have the same value
  12 # as they had before.
  13 #
  14 # Usage:
  15 #   cmake_push_check_state()
  16 #   set(CMAKE_REQUIRED_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS} -DSOME_MORE_DEF)
  17 #   check_function_exists(...)
  18 #   cmake_pop_check_state()
  19
  20 #=============================================================================
  21 # Copyright 2006-2011 Alexander Neundorf, <neundorf@kde.org>
  22 #
  23 # Distributed under the OSI-approved BSD License (the "License");
  24 # see accompanying file Copyright.txt for details.
  25 #
  26 # This software is distributed WITHOUT ANY WARRANTY; without even the
  27 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  28 # See the License for more information.
  29 #=============================================================================
  30 # (To distribute this file outside of CMake, substitute the full
  31 #  License text for the above reference.)
  32
  33
  34 macro(CMAKE_PUSH_CHECK_STATE)
  35
  36    if(NOT DEFINED _CMAKE_PUSH_CHECK_STATE_COUNTER)
  37       set(_CMAKE_PUSH_CHECK_STATE_COUNTER 0)
  38    endif()
  39
  40    math(EXPR _CMAKE_PUSH_CHECK_STATE_COUNTER "${_CMAKE_PUSH_CHECK_STATE_COUNTER}+1")
  41
  42    set(_CMAKE_REQUIRED_INCLUDES_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}    ${CMAKE_REQUIRED_INCLUDES})
  43    set(_CMAKE_REQUIRED_DEFINITIONS_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER} ${CMAKE_REQUIRED_DEFINITIONS})
  44    set(_CMAKE_REQUIRED_LIBRARIES_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}   ${CMAKE_REQUIRED_LIBRARIES})
  45    set(_CMAKE_REQUIRED_FLAGS_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}       ${CMAKE_REQUIRED_FLAGS})
  46 endmacro()
  47
  48 macro(CMAKE_POP_CHECK_STATE)
  49
  50 # don't pop more than we pushed
  51    if("${_CMAKE_PUSH_CHECK_STATE_COUNTER}" GREATER "0")
  52
  53       set(CMAKE_REQUIRED_INCLUDES    ${_CMAKE_REQUIRED_INCLUDES_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}})
  54       set(CMAKE_REQUIRED_DEFINITIONS ${_CMAKE_REQUIRED_DEFINITIONS_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}})
  55       set(CMAKE_REQUIRED_LIBRARIES   ${_CMAKE_REQUIRED_LIBRARIES_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}})
  56       set(CMAKE_REQUIRED_FLAGS       ${_CMAKE_REQUIRED_FLAGS_SAVE_${_CMAKE_PUSH_CHECK_STATE_COUNTER}})
  57
  58       math(EXPR _CMAKE_PUSH_CHECK_STATE_COUNTER "${_CMAKE_PUSH_CHECK_STATE_COUNTER}-1")
  59    endif()
  60
  61 endmacro()