dnl

dnl

dnl compilelinkrun.m4 - used to check whether a required package is properly 

dnl installed.  Compiles, links and runs a c++ test program that uses the 

dnl package to verify that the package is properly installed

dnl

dnl Expected arguments:

dnl $1: the name of the package we are testing, e.g. "OpenEXR"

dnl     used for informational messages, warnings & errors

dnl

dnl $2: the argument passed to configure specifying how to disable this test

dnl     for example:

dnl     $3 = "openexrtest" and 

dnl     "configure --disable-openexrtest" will skip the test

dnl

dnl $3: CXXFLAGS used by the test

dnl

dnl $4: LDFLAGS used by the test

dnl

dnl $5: include section of sourcecode for a c++ test program

dnl $6: body section of sourcecode for a c++ test program

dnl The test program should make use of a library that is supposed to 

dnl be tested.

dnl

dnl $7: the action to be perfomed if the test succeeds 

dnl     (e.g. AC_MSG_RESULT("OpenEXR test program succeeded"))

dnl

dnl $8   the action to be perfomed if the test fails

dnl     (e.g. AC_MSG_ERROR("OpenEXR test program failed"))

dnl

AC_DEFUN([AM_COMPILELINKRUN],

[

dnl create some local m4 "variables" so that we don't have to use numbers

define([arg_pkg_name],$1)

define([arg_disable],$2)

define([arg_cxxflags],$3)

define([arg_ldflags],$4)

define([arg_libs],$5)

define([arg_include_source],$6)

define([arg_body_source],$7)

define([arg_do_yes],$8)

define([arg_do_no],$9)

dnl check arguments

AC_ARG_ENABLE(arg_disable, [  --disable-arg_disable  Do not try to compile and run a test arg_pkg_name program],, enable_programtest=yes)

dnl

dnl if the test hasn't been disabled, then compile, link and run test program

dnl

  if test "x$enable_programtest" = "xyes" ; then

    dnl basic preliminary checks

    AC_MSG_CHECKING(for arg_pkg_name)

    test_runs="yes"

    dnl save settings and setup c++ before we start

    ac_save_CXXFLAGS="$CXXFLAGS"

    ac_save_LDFLAGS="$LDFLAGS"

    ac_save_LIBS="$LIBS"

    CXXFLAGS="$CXXFLAGS arg_cxxflags"

    LDFLAGS="$LDFLAGS arg_ldflags"

    LIBS="$LIBS arg_libs"

    AC_REQUIRE_CPP()

    AC_LANG_PUSH([C++])

    rm -f conf.testprogram

    dnl

    dnl first try a complete test - compile, link run

    dnl

    AC_RUN_IFELSE([AC_LANG_PROGRAM(arg_include_source,

                  arg_body_source; [[system("touch conf.testprogram"); ]])],

                  test_runs=yes,

                  test_runs=no,

                  [echo $ac_n "cross compiling; assumed OK... $ac_c"])

    if test "x$test_runs" = "xyes"  || test -f conf.testprogram ; then

       AC_MSG_RESULT(yes)

       ifelse([arg_do_yes], , :, [arg_do_yes])     

    else

       AC_MSG_RESULT(no)

       echo "*** Could not run the arg_pkg_name test program, checking why..."

       test_compiles="yes"

       test_links="yes"

       dnl

       dnl if the program did not run, attempt to compile only

       dnl

       AC_COMPILE_IFELSE([AC_LANG_PROGRAM(arg_include_source,

                                          arg_body_source ; )],

                      test_compiles=yes,

                      test_compiles=no)

       if test "x$test_compiles" = "xno" ; then

          echo "*** The test program could not be compiled.  Is arg_pkg_name installed?"

          echo "*** Check that the cflags (below) includes the arg_pkg_name include directory"

       else

          dnl

          dnl if the program did compile, try linking

          dnl

          AC_LINK_IFELSE([AC_LANG_PROGRAM(arg_include_source,

                                          arg_body_source ; )],

                         test_links=yes,

                         test_links=no)

          if test "x$test_links" = "xyes"; then

              echo "*** The test program compiled and staticly linked, but did not run. This "

              echo "*** usually means that the run-time linker is not finding arg_pkg_name or finding"

              echo "*** the wrong version of arg_pkg_name."

              echo "***"

              echo "*** If the linker is not finding arg_pkg_name, you'll need to set your"

              echo "*** LD_LIBRARY_PATH environment variable, or edit /etc/ld.so.conf to point"

              echo "*** to the installed location  Also, make sure you have run ldconfig if that"

              echo "*** is required on your system."

          else

              echo "*** The arg_pkg_name test program could be compiled, but could not be dynamically."

              echo "*** or statically linked."

              echo "***"

              echo "*** Make sure the LDFLAGS points to the location of the arg_pkg_name library."

              echo "*** (e.g. -L/usr/local/lib)."

              echo "*** If the run-time linker is not finding arg_pkg_name, you'll need to set your"

              echo "*** LD_LIBRARY_PATH environment variable, or edit /etc/ld.so.conf to point"

              echo "*** to the installed location  Also, make sure you have run ldconfig if that"

              echo "*** is required on your system."

          fi

       fi

       dnl

       dnl The test failed for some reason. Print out more info, 

       dnl unset flags  and signal an error.

       dnl

       echo "***"

       echo "*** Flags used by the test:"

       echo "***     cflags: $CXXFLAGS "

       echo "***     ldflags: $LDFLAGS"

       echo "***"

       echo "*** You can also run configure with --disable-arg_disable to skip this test."

       ifelse([arg_do_no], , :, [arg_do_no])

    fi

    AC_LANG_POP([C++])

    CXXFLAGS="$ac_save_CXXFLAGS"

    LDFLAGS="$ac_save_LDFLAGS"

    LIBS="$ac_save_LIBS"

    dnl

    dnl clean up

    dnl

    rm -f conf.testprogram

  fi

dnl clean up local "variables"

undefine([arg_pkg_name])

undefine([arg_disable])

undefine([arg_cxxflags])

undefine([arg_ldflags])

undefine([arg_libs])

undefine([arg_include_source])

undefine([arg_body_source])

undefine([arg_do_yes])

undefine([arg_do_no])

])