AC_INIT(Makefile.in)
AC_CONFIG_HEADER(xlconfig.h)
AC_CONFIG_AUX_DIR(config)


#
# Determine host information
#
AC_CANONICAL_HOST


#
# Set some default values
#
LIBS=-lm
UCFLAGS=-O
ULDFLAGS=
X11INCDIR_FLAG=
X11LIBDIR_FLAG=
EXTRALIBS=
EXTRAOBJS=
FOREIGN_FILE=dummy-foreign.h


#
# Determine the C compiler to use and adjust its flags
#

# Use gcc only if specified using --with-gcc or CC environment variable
AC_ARG_WITH(gcc, [  --with-gcc              use gcc compiler],
            CC=gcc,[if test -z "$CC"; then CC=cc; fi])

# Set a variable using_gcc to make checking for gcc easy below
if test `$CC -v 2>&1 | grep -c gcc` != "0" ; then using_gcc=1; fi

AC_PROG_CPP

if test "$using_gcc"; then
  # Adjust gcc flags
  case $host in
    *linux*)
      # This may be needed on other systems using gnu ld
      ULDFLAGS="$ULDFLAGS -export-dynamic"
      ;;
  esac
  case $host in
    i?86-*)
      # Enable IEEE floating point comparisons.
      UCFLAGS="$UCFLAGS -mieee-fp"
      ;;
    alpha*)
      # This needs to be checked out. Something is needed to get
      # divide by zero to produce a NaN instead of a SIGFPE.
      UCFLAGS="$UCFLAGS -mieee"
      ;;
  esac
else
  # Adjust native cc flags
  case $host in
    *aix*)
      # This needs to be checked out.
      UCFLAGS="$UCFLAGS -qmaxmem=3000 -qlanglvl=ansi"
      ;;
    alpha-dec-osf*)
      # This needs to be checked out.
      UCFLAGS="$UCFLAGS -std -ieee_with_no_inexact -Olimit 2000"
      ;;
    *unicos*)
      # This needs to be checked out.
      UCFLAGS="$UCFLAGS -h tolerant -DCRAYCC"
      ;;
    *hpux*)
      # Turn -Aa and -D_HPUX_SOURCE turn on ANSI compliance and some
      # POSIX stuff. Drop limit on optimization to make sure byte code
      # loop is optimized.
      UCFLAGS="$UCFLAGS -Aa -D_HPUX_SOURCE +Onolimit"
      ;;
    mips-sgi-irix*)
      # IRIX 6.4's cc uses -OPT:Olimit=n instead of -Olimit n. My
      # guess is that it changed with 6.0, but I don't know for sure.
      set `echo "$host_os" | sed 's/irix//' | tr '.' ' '`
      os_major=$1
      if test "$os_major" -ge 6; then
        UCFLAGS="$UCFLAGS -OPT:Olimit=2000"
      else
        UCFLAGS="$UCFLAGS -Olimit 2000"
      fi
      ;;
    mips*)
      # Most compilers for the mips architecture use this flag to
      # increase the optimization limit; this is needed for
      # xlbcode.c:bcloop
      UCFLAGS="$UCFLAGS -Olimit 2000"
      ;;
  esac
fi


#
# Adjust libraries
#
case $host in
  alpha-dec-osf*)
    # This needs to be checked out.
    EXTRALIBS="$EXTRALIBS -ldnet_stub"
    ;;
  *hpux9*|*hpux10*)
    # Need this to bring in finite. Don't know if this is needed in hpux8.
    # It isn't needed in hpux10.2 but may be in earlier hpux10's. Don't
    # know about hpux11.
    if test "$using_gcc"; then
      LIBS="-L/lib/pa1.1 $LIBS"
      EXTRALIBS="-L/lib/pa1.1 $EXTRALIBS"
    fi
    ;;
  *linux*)
    # Older Linux versions produce a SIGFPE on divide by zero unless
    # ieee library is used.
    AC_CHECK_LIB(ieee, main, [EXTRALIBS="$EXTRALIBS -lieee"])
    ;;
  *sun-solaris*)
    # Recent Solaris versions seem to have moved socket functions out
    # into the socket library
    AC_CHECK_FUNC(socket,,
      AC_CHECK_LIB(socket,socket,
        EXTRALIBS="$EXTRALIBS -lsocket",
        AC_MSG_ERROR(can't find socket functions)))
    ;;
esac


#
# Check for IEEE math support
#
case $host in
  *sun-solaris*)
    # Bring in finite and isnan on newer versions of solaris
    CFLAGS="$CFLAGS -D__EXTENSIONS__"
    UCFLAGS="$UCFLAGS -D__EXTENSIONS__"
    ;;
esac
AC_CHECK_FUNCS(finite isnan)


#
# Check for some other functions
#
AC_CHECK_FUNCS(memmove difftime matherr)


#
# Check for POSIX sigsetjmp and friends. 
# Use grep for sigjmp_buf since sigsetjmp/siglongjmp may be macros.
#
AC_EGREP_HEADER(sigjmp_buf, setjmp.h, AC_DEFINE(HAVE_SIGSETJMP))


#
# Determine the graphics system to use
#
AC_PATH_X
if test "$no_x"; then
  GRAPHSYS=GNUPLOT
else
  GRAPHSYS=X11WINDOWS
  if test "$x_includes"; then X11INCDIR_FLAG="-I$x_includes"; fi
  if test "$x_libraries"; then X11LIBDIR_FLAG="-L$x_libraries"; fi
fi


#
# Check for dynamic loaing support
#

# First try for SysVR4-style dlfcn support
AC_CHECK_FUNC(dlopen,[
  FOREIGN_FILE="sysvr4-foreign.h"
  foreign=1
  AC_DEFINE(HAVE_DLOPEN)  # not sure why I need this but I seem to
  AC_DEFINE(HAVE_FOREIGN)],
  AC_CHECK_LIB(dl,dlopen,[
    FOREIGN_FILE="sysvr4-foreign.h"
    foreign=1
    AC_DEFINE(HAVE_DLOPEN)  # not sure why I need this but I seem to
    AC_DEFINE(HAVE_FOREIGN)
    EXTRALIBS="$EXTRALIBS -ldl"]))

# Next try some os-specific solutions
if test ! "$foreign"; then
  case $host in
    *aix*)
      # This needs to be checked
      ULDFLAGS="-bE:xlisp.exp -bM:SRE"
      link_sources="$link_sources machines/aix/xlisp.exp"
      link_sources="$link_sources machines/aix/dynload/dlfcn.c"
      link_targets ="$link_targets xlisp.exp dlfcn.c"
      FOREIGN_FILE="sysvr4-foreign.h";
      AC_DEFINE(HAVE_FOREIGN)
      AC_DEFINE(HAVE_DLOPEN)
      UCFLAGS="$UCFLAGS -Imachines/aix/dynload"
      EXTRAOBJS=dlfcn.o
      EXTRALIBS="$EXTRALIBS -lld"
      foreign=1
      ;;
    *hpux*)
      FOREIGN_FILE="sysvr4-foreign.h"
      AC_DEFINE(HAVE_FOREIGN)
      AC_DEFINE(HAVE_DLOPEN)
      UCFLAGS="$UCFLAGS -Imachines/hpux/dlfcn"
      EXTRAOBJS="$EXTRAOBJS dlfcn.o"
      link_sources="$link_sources machines/hpux/dlfcn/dlfcn.c"
      link_targets="$link_targets dlfcn.c"
      EXTRALIBS="$EXTRALIBS -ldld"
      ULDFLAGS="$ULDFLAGS -Wl,-E"
      foreign=1
      ;;
    mips-dec-ultrix*)
      FOREIGN_FILE="pmax-foreign.h"
      AC_DEFINE(HAVE_FOREIGN)
      ULDFLAGS="$ULDFLAGS -Wl,-D -Wl,c00000"
      foreign=1
      ;;
    vax*)
      FOREIGN_FILE="bsd-foreign.h"
      AC_DEFINE(HAVE_FOREIGN)
      foreign=1
      ;;
    *bsd*)
      FOREIGN_FILE="bsd-foreign.h"
      AC_DEFINE(HAVE_FOREIGN)
      foreign=1
      ;;
  esac
fi
# As last resort try for GNU dld
if test ! "$foreign"; then
  AC_CHECK_LIB(dld,dld_init,[
    FOREIGN_FILE="dld-foreign.h"
    foreign=1
    AC_DEFINE(HAVE_FOREIGN)
    EXTRALIBS="$EXTRALIBS -ldld"])
fi


#
# Determine how to create shared libraries -- adapted from Tcl 8.0
#
SHLIB_CFLAGS=""
SHLIB_LD_LIBS=""
case $host in
  *aix*)  # **** this doesn't work yet
    SHLIB_LD="$fullSrcDir/ldAix /bin/ld -bhalt:4 -bM:SRE -bE:lib.exp -H512 -T512 -bnoentry"
    SHLIB_LD_LIBS='${LIBS}'
    ;;
  alpha-dec-osf*)
    # check this out
    SHLIB_LD='ld -shared -expect_unresolved "*"'
    ;;
  *hpux*)
    SHLIB_CFLAGS="+z -Aa -D_HPUX_SOURCE"
    SHLIB_LD="ld -b"
    ;;
  *irix*)
    SHLIB_LD="ld -shared -rdata_shared"
    ;;
  *linux*)
    SHLIB_CFLAGS="-fPIC"
    SHLIB_LD="${CC} -shared"
    ;;
  *netbsd*|*freebsd*|*openbsd*)
    SHLIB_CFLAGS="-fpic"
    SHLIB_LD="ld -Bshareable -x"
    ;;
  *sunos*)
    SHLIB_CFLAGS="-PIC"
    SHLIB_LD="ld"
    ;;
  *solaris*)
    SHLIB_CFLAGS="-KPIC"
    SHLIB_LD="/usr/ccs/bin/ld -G -z text"
    SHLIB_LD_LIBS='${LIBS}'
    ;;
  *)
    AC_MSG_WARN(Don't know how to create shared libraries on this platform)
esac

# If we're running gcc, then change the C flags for compiling shared
# libraries to the right flags for gcc, instead of those for the
# standard manufacturer compiler.
if test `$CC -v 2>&1 | grep -c gcc` != "0" ; then
  case $system in
    *aix*)
      ;;
    *irix*)
      ;;
    *netbsd*|*freebsd*|*openbsd*|*linux*)
      ;;
    *)
      SHLIB_CFLAGS="-fPIC"
      ;;
  esac
fi


#
# Register variables for substitution
#
AC_SUBST(GRAPHSYS)
AC_SUBST(X11INCDIR_FLAG)
AC_SUBST(X11LIBDIR_FLAG)
AC_SUBST(UCFLAGS)
AC_SUBST(ULDFLAGS)
AC_SUBST(EXTRALIBS)
AC_SUBST(EXTRAOBJS)
AC_SUBST(FOREIGN_FILE)
AC_SUBST(CC)
AC_SUBST(CC)
AC_SUBST(SHLIB_CFLAGS)
AC_SUBST(SHLIB_LD)
AC_SUBST(SHLIB_LD_LIBS)

echo GRAPHSYS       = $GRAPHSYS
echo X11INCDIR_FLAG = $X11INCDIR_FLAG
echo X11LIBDIR_FLAG = $X11LIBDIR_FLAG
echo UCFLAGS        = $UCFLAGS
echo ULDFLAGS       = $ULDFLAGS
echo EXTRALIBS      = $EXTRALIBS
echo EXTRAOBJS      = $EXTRAOBJS
echo FOREIGN_FILE   = $FOREIGN_FILE
echo CC             = $CC
echo SHLIB_CFLAGS   = $SHLIB_CFLAGS
echo SHLIB_LD       = $SHLIB_LD
echo SHLIB_LD_LIBS  = $SHLIB_LD_LIBS

AC_LINK_FILES($link_sources,$link_targets)
AC_OUTPUT(Makefile shlibconfig.sh)