dnl Process this file with autoconf to produce a configure script.
dnl
dnl We might want AC_WORDS_BIGENDIAN in the future.
dnl We might want AC_CHAR_UNSIGNED in the future.
dnl
dnl The -cckr (K&R) flag is for the IRIX C compiler.  If this is left
dnl out, scheme48vm.c breaks because the rather pedantic SGI compiler
dnl decides that a char is not the same thing as an unsigned char.
dnl - Bryan O'Sullivan 3/94
dnl Note, this test didn't work correctly on Sun's which take -cckr as a
dnl synonym for -c. (HCC)

dnl JMG: hack hack hack
AR=${AR-"ar cq"}


define(S48_CFLAG_CKR, [dnl
	if test "z$GCC" = z; then
		AC_MSG_CHECKING([-cckr])
		oldCFLAGS="$CFLAGS"
		CFLAGS="$CFLAGS -cckr"
		AC_TRY_RUN([int main() { return 0;}],
			[AC_MSG_RESULT(yes)],
			[AC_MSG_RESULT(no)
				CFLAGS="$oldCFLAGS"],
			[AC_MSG_RESULT(no)
				CFLAGS="$oldCFLAGS"])
	fi
])dnl
dnl
define(S48_POSIX_LIBC, [dnl
echo checking for RISC/OS POSIX library lossage
if test -f /usr/posix/usr/lib/libc.a; then
  LIBS="${LIBS} /usr/posix/usr/lib/libc.a"
fi
])dnl
dnl
dnl Run AC_PROG_CC, but don't accept it's changes to CFLAGS.
dnl For some insane reason, it sets CFLAGS to either `-O' or `-g -O' for gcc.
dnl I don't want the silly -g (because if you are using nlist, you can't strip
dnl the binary), I want -O2 for gcc and -O for other C compilers.
define(S48_PROG_CC, [dnl
	oldCFLAGS="$CFLAGS"
	AC_PROG_CC
	if test "z$oldCFLAGS" = z; then
		if test "z$GCC" = z; then
			CFLAGS='-O'
		else
			CFLAGS='-O2'
		fi
	fi
])dnl
dnl
dnl Linux/ELF systems need the -rdynamic flag when linking so that
dnl dlsym() can find symbols in the executable.
dnl Note, on some Sun's, you can link with -rdynamic but the resulting
dnl a.out always core dumps.
define(S48_RDYNAMIC, [dnl
	AC_MSG_CHECKING([link with -rdynamic])
	AC_TRY_COMPILE([],
[#if defined(__linux__) && defined(__ELF__)
	this must not compile
#endif],
		[AC_MSG_RESULT(no)],
		[AC_MSG_RESULT(yes)
			LDFLAGS="$LDFLAGS -rdynamic"])
])dnl
dnl
define(S48_USCORE, [dnl
	AC_MSG_CHECKING([underscore before symbols])
	echo 'main() { return 0; } fnord() {}' >conftest.c
	if ${CC} ${CFLAGS} ${CPPFLAGS} ${LDFLAGS} conftest.c ${LIBS} &&
	nm a.out | grep _fnord >/dev/null; then
		AC_MSG_RESULT([yes])
		AC_DEFINE(USCORE)
	else
		AC_MSG_RESULT([no])
	fi
	rm -f conftest.c a.out
])dnl
dnl
dnl -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
AC_DEFUN(SCSH_TZNAME,[
  AC_MSG_CHECKING(for tzname)
  AC_CACHE_VAL(scsh_cv_tzname,[
    AC_TRY_COMPILE([#include <time.h>], 
		   [return (int) tzname;],
                   scsh_cv_tzname=yes,
                   scsh_cv_tzname=no)])
  AC_MSG_RESULT($scsh_cv_tzname)
  if test $scsh_cv_tzname = yes; then
    AC_DEFINE(HAVE_TZNAME)
  fi
])

dnl -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
AC_DEFUN(SCSH_GMTOFF,[
  AC_MSG_CHECKING(for gmtoff)
  AC_CACHE_VAL(scsh_cv_gmtoff,[
    AC_TRY_COMPILE([#include <time.h>], 
		   [struct tm time;
		    return time.tm_gmtoff;],
                   scsh_cv_gmtoff=yes,
                   scsh_cv_gmtoff=no)])
  AC_MSG_RESULT($scsh_cv_gmtoff)
  if test $scsh_cv_gmtoff = yes; then
    AC_DEFINE(HAVE_GMTOFF)
  fi
])

dnl -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
AC_INIT(c/scheme48vm.c)
     AC_CONFIG_HEADER(c/sysdep.h)
     S48_PROG_CC
     AC_ISC_POSIX
     dnl set the cross-compile flag before we try anything.
     AC_TRY_RUN([int main() { return 0;}], [], [], [true])
     S48_CFLAG_CKR
     AC_PROG_INSTALL
     AC_CHECK_LIB(m, main)
     AC_CHECK_LIB(dl, main)
     AC_CHECK_LIB(mld, main)
     AC_CHECK_LIB(nsl, main)
     AC_CHECK_LIB(gen, main)
     AC_CHECK_LIB(socket, main)
     AC_CHECK_LIB(sun, getpwnam)
     dnl Solaris 2.3 seems to need -lelf for nlist().  (tnx Bryan O'Sullivan)
     AC_CHECK_LIB(elf, main)
     S48_POSIX_LIBC
     AC_CONST
     AC_RETSIGTYPE
     AC_CHECK_HEADERS(libgen.h sys/timeb.h posix/time.h)
     AC_CHECK_HEADERS(sys/select.h)
     AC_CHECK_FUNCS(gettimeofday ftime nlist select setitimer sigaction)
     AC_CHECK_FUNC(dlopen, AC_DEFINE(HAVE_DLOPEN),
			   AC_CHECK_FUNC(nlist, [LIBOBJS="$LIBOBJS c/fake/libdl1.c],
						[LIBOBJS="$LIBOBJS c/fake/libdl2.c]))
     AC_CHECK_FUNCS(socket chroot)
     AC_CHECK_FUNC(strerror, AC_DEFINE(HAVE_STRERROR),
			      [LIBOBJS="$LIBOBJS c/fake/strerror.o"])
     AC_MSG_CHECKING([n_name])
     AC_TRY_LINK([#include <nlist.h>],
		 [struct nlist name_list;
		  name_list.n_name = "foo";],
		 AC_DEFINE(NLIST_HAS_N_NAME)
		 AC_MSG_RESULT([yes]),
		 AC_MSG_RESULT([no]))
     AC_MSG_CHECKING([__NEXT__])
     AC_TRY_LINK(,[
#ifdef	__NeXT__
return 0;
#else
fail
#endif
],
		CC="$CC -posix"
		AC_DEFINE(HAVE_SIGACTION)
		AC_MSG_RESULT([yes]),
		AC_MSG_RESULT([no]))
     S48_USCORE
     S48_RDYNAMIC
     AC_SUBST(CFLAGS)
     AC_SUBST(LIBOBJS)
     AC_SUBST(LDFLAGS)
     SCSH_TZNAME
     SCSH_GMTOFF	
AC_OUTPUT(Makefile)