# - Check if the prototype for a function exists.
# CHECK_PROTOTYPE_EXISTS (FUNCTION HEADER VARIABLE)
#
#  FUNCTION - the name of the function you are looking for
#  HEADER - the header(s) where the prototype should be declared
#  VARIABLE - variable to store the result
#
# 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

# Copyright (c) 2006, Alexander Neundorf, <neundorf@kde.org>
#
# Redistribution and use is allowed according to the terms of the BSD license.
# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
#
# Source: KDE/kdelibs
# <http://websvn.kde.org/trunk/KDE/kdelibs/cmake/modules/CheckPrototypeExists.cmake?pathrev=776742>
#
INCLUDE(CheckCXXSourceCompiles)

MACRO(CHECK_PROTOTYPE_EXISTS _SYMBOL _HEADER _RESULT)
  SET(_INCLUDE_FILES)
  FOREACH (it ${_HEADER})
    SET(_INCLUDE_FILES "${_INCLUDE_FILES}#include <${it}>\n")
  ENDFOREACH (it)
  
  SET(_CHECK_PROTO_EXISTS_SOURCE_CODE "
${_INCLUDE_FILES}
int main()
{
#ifndef ${_SYMBOL}
    int i = sizeof(&${_SYMBOL});
#endif
    return 0;
}
")
  CHECK_CXX_SOURCE_COMPILES("${_CHECK_PROTO_EXISTS_SOURCE_CODE}" ${_RESULT})
ENDMACRO(CHECK_PROTOTYPE_EXISTS _SYMBOL _HEADER _RESULT)