5.1.5 Autoconf tests

If you work on a project that uses Autoconf (see (autoconf)GNU Autoconf) to help find installed libraries, the suggestions in the previous section are not the entire story. There are a few methods to detect and incorporate Shishi into your Autoconf based package. The preferred approach, is to use Libtool in your project, and use the normal Autoconf header file and library tests.

5.1.5.1 Autoconf test via ‘pkg-config’

If your audience is a typical GNU/Linux desktop, you can often assume they have the ‘pkg-config’ tool installed, in which you can use its Autoconf M4 macro to find and set up your package for use with Shishi. The following illustrate this scenario.

AC_ARG_ENABLE(kerberos_v5,
	AC_HELP_STRING([--disable-kerberos_v5],
                       [don't use the KERBEROS_V5 mechanism]),
	kerberos_v5=$enableval)
if test "$kerberos_v5" != "no" ; then
	PKG_CHECK_MODULES(SHISHI, shishi >= 0.0.0,
			[kerberos_v5=yes],
                        [kerberos_v5=no])
	if test "$kerberos_v5" != "yes" ; then
		kerberos_v5=no
		AC_MSG_WARN([shishi not found, disabling Kerberos 5])
	else
		kerberos_v5=yes
		AC_DEFINE(USE_KERBEROS_V5, 1,
                          [Define to 1 if you want Kerberos 5.])
	fi
fi
AC_MSG_CHECKING([if Kerberos 5 should be used])
AC_MSG_RESULT($kerberos_v5)

5.1.5.2 Standalone Autoconf test using Libtool

If your package uses Libtool(see (libtool)GNU Libtool), you can use the normal Autoconf tests to find the Shishi library and rely on the Libtool dependency tracking to include the proper dependency libraries (e.g., Libidn). The following illustrate this scenario.

AC_CHECK_HEADER(shishi.h,
	AC_CHECK_LIB(shishi, shishi_check_version,
		[kerberos5=yes AC_SUBST(SHISHI_LIBS, -lshishi)],
		kerberos5=no),
	kerberos5=no)
AC_ARG_ENABLE(kerberos5,
	AC_HELP_STRING([--disable-kerberos5],
                       [disable Kerberos 5 unconditionally]),
	kerberos5=$enableval)
if test "$kerberos5" != "no" ; then
	AC_DEFINE(USE_KERBEROS_V5, 1,
		  [Define to 1 if you want Kerberos 5.])
else
	AC_MSG_WARN([Shishi not found, disabling Kerberos 5])
fi
AC_MSG_CHECKING([if Kerberos 5 should be used])
AC_MSG_RESULT($kerberos5)

5.1.5.3 Standalone Autoconf test

If your package does not use Libtool, as well as detecting the Shishi library as in the previous case, you must also detect whatever dependencies Shishi requires to work (e.g., libidn). Since the dependencies are in a state of flux, we do not provide an example and we do not recommend this approach, unless you are experienced developer.