Adding upstream version 1.23.0.upstream/1.23.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

11 files changed, 3731 insertions, 0 deletions

diff --git a/m4/ax_compare_version.m4 b/m4/ax_compare_version.m4
new file mode 100644
index 0000000..74dc0fd
--- /dev/null
+++ b/m4/ax_compare_version.m4
@@ -0,0 +1,177 @@
+# ===========================================================================
+#    http://www.gnu.org/software/autoconf-archive/ax_compare_version.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPARE_VERSION(VERSION_A, OP, VERSION_B, [ACTION-IF-TRUE], [ACTION-IF-FALSE])
+#
+# DESCRIPTION
+#
+#   This macro compares two version strings. Due to the various number of
+#   minor-version numbers that can exist, and the fact that string
+#   comparisons are not compatible with numeric comparisons, this is not
+#   necessarily trivial to do in a autoconf script. This macro makes doing
+#   these comparisons easy.
+#
+#   The six basic comparisons are available, as well as checking equality
+#   limited to a certain number of minor-version levels.
+#
+#   The operator OP determines what type of comparison to do, and can be one
+#   of:
+#
+#    eq  - equal (test A == B)
+#    ne  - not equal (test A != B)
+#    le  - less than or equal (test A <= B)
+#    ge  - greater than or equal (test A >= B)
+#    lt  - less than (test A < B)
+#    gt  - greater than (test A > B)
+#
+#   Additionally, the eq and ne operator can have a number after it to limit
+#   the test to that number of minor versions.
+#
+#    eq0 - equal up to the length of the shorter version
+#    ne0 - not equal up to the length of the shorter version
+#    eqN - equal up to N sub-version levels
+#    neN - not equal up to N sub-version levels
+#
+#   When the condition is true, shell commands ACTION-IF-TRUE are run,
+#   otherwise shell commands ACTION-IF-FALSE are run. The environment
+#   variable 'ax_compare_version' is always set to either 'true' or 'false'
+#   as well.
+#
+#   Examples:
+#
+#     AX_COMPARE_VERSION([3.15.7],[lt],[3.15.8])
+#     AX_COMPARE_VERSION([3.15],[lt],[3.15.8])
+#
+#   would both be true.
+#
+#     AX_COMPARE_VERSION([3.15.7],[eq],[3.15.8])
+#     AX_COMPARE_VERSION([3.15],[gt],[3.15.8])
+#
+#   would both be false.
+#
+#     AX_COMPARE_VERSION([3.15.7],[eq2],[3.15.8])
+#
+#   would be true because it is only comparing two minor versions.
+#
+#     AX_COMPARE_VERSION([3.15.7],[eq0],[3.15])
+#
+#   would be true because it is only comparing the lesser number of minor
+#   versions of the two values.
+#
+#   Note: The characters that separate the version numbers do not matter. An
+#   empty string is the same as version 0. OP is evaluated by autoconf, not
+#   configure, so must be a string, not a variable.
+#
+#   The author would like to acknowledge Guido Draheim whose advice about
+#   the m4_case and m4_ifvaln functions make this macro only include the
+#   portions necessary to perform the specific comparison specified by the
+#   OP argument in the final configure script.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Tim Toolan <toolan@ele.uri.edu>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 11
+
+dnl #########################################################################
+AC_DEFUN([AX_COMPARE_VERSION], [
+  AC_REQUIRE([AC_PROG_AWK])
+
+  # Used to indicate true or false condition
+  ax_compare_version=false
+
+  # Convert the two version strings to be compared into a format that
+  # allows a simple string comparison.  The end result is that a version
+  # string of the form 1.12.5-r617 will be converted to the form
+  # 0001001200050617.  In other words, each number is zero padded to four
+  # digits, and non digits are removed.
+  AS_VAR_PUSHDEF([A],[ax_compare_version_A])
+  A=`echo "$1" | sed -e 's/\([[0-9]]*\)/Z\1Z/g' \
+                     -e 's/Z\([[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/Z\([[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/Z\([[0-9]][[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/[[^0-9]]//g'`
+
+  AS_VAR_PUSHDEF([B],[ax_compare_version_B])
+  B=`echo "$3" | sed -e 's/\([[0-9]]*\)/Z\1Z/g' \
+                     -e 's/Z\([[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/Z\([[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/Z\([[0-9]][[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+                     -e 's/[[^0-9]]//g'`
+
+  dnl # In the case of le, ge, lt, and gt, the strings are sorted as necessary
+  dnl # then the first line is used to determine if the condition is true.
+  dnl # The sed right after the echo is to remove any indented white space.
+  m4_case(m4_tolower($2),
+  [lt],[
+    ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort -r | sed "s/x${A}/false/;s/x${B}/true/;1q"`
+  ],
+  [gt],[
+    ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort | sed "s/x${A}/false/;s/x${B}/true/;1q"`
+  ],
+  [le],[
+    ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort | sed "s/x${A}/true/;s/x${B}/false/;1q"`
+  ],
+  [ge],[
+    ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort -r | sed "s/x${A}/true/;s/x${B}/false/;1q"`
+  ],[
+    dnl Split the operator from the subversion count if present.
+    m4_bmatch(m4_substr($2,2),
+    [0],[
+      # A count of zero means use the length of the shorter version.
+      # Determine the number of characters in A and B.
+      ax_compare_version_len_A=`echo "$A" | $AWK '{print(length)}'`
+      ax_compare_version_len_B=`echo "$B" | $AWK '{print(length)}'`
+
+      # Set A to no more than B's length and B to no more than A's length.
+      A=`echo "$A" | sed "s/\(.\{$ax_compare_version_len_B\}\).*/\1/"`
+      B=`echo "$B" | sed "s/\(.\{$ax_compare_version_len_A\}\).*/\1/"`
+    ],
+    [[0-9]+],[
+      # A count greater than zero means use only that many subversions
+      A=`echo "$A" | sed "s/\(\([[0-9]]\{4\}\)\{m4_substr($2,2)\}\).*/\1/"`
+      B=`echo "$B" | sed "s/\(\([[0-9]]\{4\}\)\{m4_substr($2,2)\}\).*/\1/"`
+    ],
+    [.+],[
+      AC_WARNING(
+        [illegal OP numeric parameter: $2])
+    ],[])
+
+    # Pad zeros at end of numbers to make same length.
+    ax_compare_version_tmp_A="$A`echo $B | sed 's/./0/g'`"
+    B="$B`echo $A | sed 's/./0/g'`"
+    A="$ax_compare_version_tmp_A"
+
+    # Check for equality or inequality as necessary.
+    m4_case(m4_tolower(m4_substr($2,0,2)),
+    [eq],[
+      test "x$A" = "x$B" && ax_compare_version=true
+    ],
+    [ne],[
+      test "x$A" != "x$B" && ax_compare_version=true
+    ],[
+      AC_WARNING([illegal OP parameter: $2])
+    ])
+  ])
+
+  AS_VAR_POPDEF([A])dnl
+  AS_VAR_POPDEF([B])dnl
+
+  dnl # Execute ACTION-IF-TRUE / ACTION-IF-FALSE.
+  if test "$ax_compare_version" = "true" ; then
+    m4_ifvaln([$4],[$4],[:])dnl
+    m4_ifvaln([$5],[else $5])dnl
+  fi
+]) dnl AX_COMPARE_VERSION
diff --git a/m4/ax_prog_perl_version.m4 b/m4/ax_prog_perl_version.m4
new file mode 100644
index 0000000..d794c1a
--- /dev/null
+++ b/m4/ax_prog_perl_version.m4
@@ -0,0 +1,70 @@
+# ===========================================================================
+#   http://www.gnu.org/software/autoconf-archive/ax_prog_perl_version.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_PROG_PERL_VERSION([VERSION],[ACTION-IF-TRUE],[ACTION-IF-FALSE])
+#
+# DESCRIPTION
+#
+#   Makes sure that perl supports the version indicated. If true the shell
+#   commands in ACTION-IF-TRUE are executed. If not the shell commands in
+#   ACTION-IF-FALSE are run. Note if $PERL is not set (for example by
+#   running AC_CHECK_PROG or AC_PATH_PROG) the macro will fail.
+#
+#   Example:
+#
+#     AC_PATH_PROG([PERL],[perl])
+#     AX_PROG_PERL_VERSION([5.8.0],[ ... ],[ ... ])
+#
+#   This will check to make sure that the perl you have supports at least
+#   version 5.8.0.
+#
+#   NOTE: This macro uses the $PERL variable to perform the check.
+#   AX_WITH_PERL can be used to set that variable prior to running this
+#   macro. The $PERL_VERSION variable will be valorized with the detected
+#   version.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Francesco Salvestrini <salvestrini@users.sourceforge.net>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 12
+
+AC_DEFUN([AX_PROG_PERL_VERSION],[
+    AC_REQUIRE([AC_PROG_SED])
+    AC_REQUIRE([AC_PROG_GREP])
+
+    AS_IF([test -n "$PERL"],[
+        ax_perl_version="$1"
+
+        AC_MSG_CHECKING([for perl version])
+        changequote(<<,>>)
+        perl_version=`$PERL --version 2>&1 \
+          | $SED -n -e '/This is perl/b inspect
+b
+: inspect
+s/.* (\{0,1\}v\([0-9]*\.[0-9]*\.[0-9]*\))\{0,1\} .*/\1/;p'`
+        changequote([,])
+        AC_MSG_RESULT($perl_version)
+
+	AC_SUBST([PERL_VERSION],[$perl_version])
+
+        AX_COMPARE_VERSION([$ax_perl_version],[le],[$perl_version],[
+	    :
+            $2
+        ],[
+	    :
+            $3
+        ])
+    ],[
+        AC_MSG_WARN([could not find the perl interpreter])
+        $3
+    ])
+])
diff --git a/m4/codeset.m4 b/m4/codeset.m4
new file mode 100644
index 0000000..4f09722
--- /dev/null
+++ b/m4/codeset.m4
@@ -0,0 +1,23 @@
+# codeset.m4 serial 5 (gettext-0.18.2)
+dnl Copyright (C) 2000-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+AC_DEFUN([AM_LANGINFO_CODESET],
+[
+  AC_CACHE_CHECK([for nl_langinfo and CODESET], [am_cv_langinfo_codeset],
+    [AC_LINK_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <langinfo.h>]],
+          [[char* cs = nl_langinfo(CODESET); return !cs;]])],
+       [am_cv_langinfo_codeset=yes],
+       [am_cv_langinfo_codeset=no])
+    ])
+  if test $am_cv_langinfo_codeset = yes; then
+    AC_DEFINE([HAVE_LANGINFO_CODESET], [1],
+      [Define if you have <langinfo.h> and nl_langinfo(CODESET).])
+  fi
+])
diff --git a/m4/fcntl-o.m4 b/m4/fcntl-o.m4
new file mode 100644
index 0000000..b0605e4
--- /dev/null
+++ b/m4/fcntl-o.m4
@@ -0,0 +1,134 @@
+# fcntl-o.m4 serial 4
+dnl Copyright (C) 2006-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by Paul Eggert.
+
+# Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
+# Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
+# Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
+AC_DEFUN([gl_FCNTL_O_FLAGS],
+[
+  dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
+  dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes
+  dnl AC_GNU_SOURCE.
+  m4_ifdef([AC_USE_SYSTEM_EXTENSIONS],
+    [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
+    [AC_REQUIRE([AC_GNU_SOURCE])])
+
+  AC_CHECK_HEADERS_ONCE([unistd.h])
+  AC_CHECK_FUNCS_ONCE([symlink])
+  AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
+    [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <sys/types.h>
+           #include <sys/stat.h>
+           #if HAVE_UNISTD_H
+           # include <unistd.h>
+           #else /* on Windows with MSVC */
+           # include <io.h>
+           # include <stdlib.h>
+           # defined sleep(n) _sleep ((n) * 1000)
+           #endif
+           #include <fcntl.h>
+           #ifndef O_NOATIME
+            #define O_NOATIME 0
+           #endif
+           #ifndef O_NOFOLLOW
+            #define O_NOFOLLOW 0
+           #endif
+           static int const constants[] =
+            {
+              O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
+              O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
+            };
+          ]],
+          [[
+            int result = !constants;
+            #if HAVE_SYMLINK
+            {
+              static char const sym[] = "conftest.sym";
+              if (symlink ("/dev/null", sym) != 0)
+                result |= 2;
+              else
+                {
+                  int fd = open (sym, O_WRONLY | O_NOFOLLOW | O_CREAT, 0);
+                  if (fd >= 0)
+                    {
+                      close (fd);
+                      result |= 4;
+                    }
+                }
+              if (unlink (sym) != 0 || symlink (".", sym) != 0)
+                result |= 2;
+              else
+                {
+                  int fd = open (sym, O_RDONLY | O_NOFOLLOW);
+                  if (fd >= 0)
+                    {
+                      close (fd);
+                      result |= 4;
+                    }
+                }
+              unlink (sym);
+            }
+            #endif
+            {
+              static char const file[] = "confdefs.h";
+              int fd = open (file, O_RDONLY | O_NOATIME);
+              if (fd < 0)
+                result |= 8;
+              else
+                {
+                  struct stat st0;
+                  if (fstat (fd, &st0) != 0)
+                    result |= 16;
+                  else
+                    {
+                      char c;
+                      sleep (1);
+                      if (read (fd, &c, 1) != 1)
+                        result |= 24;
+                      else
+                        {
+                          if (close (fd) != 0)
+                            result |= 32;
+                          else
+                            {
+                              struct stat st1;
+                              if (stat (file, &st1) != 0)
+                                result |= 40;
+                              else
+                                if (st0.st_atime != st1.st_atime)
+                                  result |= 64;
+                            }
+                        }
+                    }
+                }
+            }
+            return result;]])],
+       [gl_cv_header_working_fcntl_h=yes],
+       [case $? in #(
+        4) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
+        64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
+        68) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
+         *) gl_cv_header_working_fcntl_h='no';;
+        esac],
+       [gl_cv_header_working_fcntl_h=cross-compiling])])
+
+  case $gl_cv_header_working_fcntl_h in #(
+  *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
+  *) ac_val=1;;
+  esac
+  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
+    [Define to 1 if O_NOATIME works.])
+
+  case $gl_cv_header_working_fcntl_h in #(
+  *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
+  *) ac_val=1;;
+  esac
+  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
+    [Define to 1 if O_NOFOLLOW works.])
+])
diff --git a/m4/glibc21.m4 b/m4/glibc21.m4
new file mode 100644
index 0000000..818b49f
--- /dev/null
+++ b/m4/glibc21.m4
@@ -0,0 +1,33 @@
+# glibc21.m4 serial 5
+dnl Copyright (C) 2000-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# Test for the GNU C Library, version 2.1 or newer, or uClibc.
+# From Bruno Haible.
+
+AC_DEFUN([gl_GLIBC21],
+  [
+    AC_CACHE_CHECK([whether we are using the GNU C Library >= 2.1 or uClibc],
+      [ac_cv_gnu_library_2_1],
+      [AC_EGREP_CPP([Lucky],
+        [
+#include <features.h>
+#ifdef __GNU_LIBRARY__
+ #if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1) || (__GLIBC__ > 2)
+  Lucky GNU user
+ #endif
+#endif
+#ifdef __UCLIBC__
+ Lucky user
+#endif
+        ],
+        [ac_cv_gnu_library_2_1=yes],
+        [ac_cv_gnu_library_2_1=no])
+      ]
+    )
+    AC_SUBST([GLIBC21])
+    GLIBC21="$ac_cv_gnu_library_2_1"
+  ]
+)
diff --git a/m4/groff.m4 b/m4/groff.m4
new file mode 100644
index 0000000..19bf7f9
--- /dev/null
+++ b/m4/groff.m4
@@ -0,0 +1,1886 @@
+# Autoconf macros for groff.
+# Copyright (C) 1989-2023 Free Software Foundation, Inc.
+#
+# This file is part of groff.
+#
+# groff is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# groff is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Locate a print spooler for certain output formats.
+
+AC_DEFUN([GROFF_PRINT], [
+  groff_have_spooler=no
+  if test -z "$PSPRINT"
+  then
+    AC_CHECK_PROGS([LPR], [lpr])
+    AC_CHECK_PROGS([LP], [lp])
+    if test -n "$LPR" && test -n "$LP"
+     then
+      # HP-UX provides an lpr command that emulates lpr using lp,
+      # but it doesn't have lpq; in this case we want to use lp
+      # rather than lpr.
+      AC_CHECK_PROGS([LPQ], [lpq])
+      test -n "$LPQ" || LPR=
+    fi
+    if test -n "$LPR"
+    then
+      PSPRINT="$LPR"
+    elif test -n "$LP"
+    then
+      PSPRINT="$LP"
+    fi
+  fi
+
+  if test -n "$PSPRINT"
+  then
+    groff_have_spooler="$PSPRINT"
+    AC_SUBST([PSPRINT])
+    # Figure out DVIPRINT from PSPRINT.
+    AC_MSG_CHECKING([option to use when spooling DVI files])
+    spooler_option=none
+    if test -n "$PSPRINT" && test -z "$DVIPRINT"
+    then
+      if test "$PSPRINT" = lpr
+      then
+        spooler_option=-d
+        DVIPRINT="$PSPRINT $spooler_option"
+      else
+        DVIPRINT="$PSPRINT"
+      fi
+    fi
+    AC_SUBST([DVIPRINT])
+    AC_MSG_RESULT([$spooler_option])
+  fi
+])
+
+# Bison-generated parsers have problems with C++ compilers other than
+# g++.  Thus, byacc is preferred over bison.  If no yacc program is
+# available, we issue an error only if not building from a distribution
+# archive, because files generated by a yacc are already present there.
+
+AC_DEFUN([GROFF_PROG_YACC], [
+  AC_CHECK_PROGS([YACC], [byacc 'bison -y' yacc], [missing])
+  if ! test -f "$srcdir"/.tarball-version
+  then
+    if test "$YACC" = missing
+    then
+      AC_MSG_ERROR([could not find 'byacc', 'bison', or 'yacc'], 1)
+    fi
+  fi
+])
+
+# We need Perl 5.6.1 or newer.
+
+AC_DEFUN([GROFF_PERL], [
+  PERLVERSION=v5.6.1
+  AC_PATH_PROG([PERL], [perl], [no])
+  if test "$PERL" = no
+  then
+    AC_MSG_ERROR([perl binary not found], 1)
+  fi
+  AX_PROG_PERL_VERSION([$PERLVERSION], true,
+    AC_MSG_ERROR([perl version is too old], 1))
+])
+
+# We need m4 to generate some man pages.
+
+AC_DEFUN([GROFF_PROG_M4], [
+  AC_CHECK_PROGS([M4], [m4], [missing])
+  if test "$M4" = missing
+  then
+    AC_MSG_ERROR([could not find 'm4'], 1)
+  fi
+])
+
+# We need makeinfo from Texinfo 5.0 or newer, for @codequoteundirected.
+# The minor version checking logic is present for future needs.
+
+AC_DEFUN([GROFF_PROG_MAKEINFO], [
+  # By default automake will set MAKEINFO to MAKEINFO = ${SHELL} <top
+  # src dir>/build-aux/missing makeinfo.  As we need a more precise
+  # check of makeinfo version, we don't use it.
+  MAKEINFO=
+  missing=
+  AC_CHECK_PROG([MAKEINFO], [makeinfo], [makeinfo])
+  if test -z "$MAKEINFO"
+  then
+    missing="missing 'makeinfo'"
+  else
+    AC_MSG_CHECKING([for makeinfo version])
+    # We need an additional level of quoting to make sed's regexps
+    # work.
+    [makeinfo_version=`$MAKEINFO --version 2>&1 \
+     | sed -e 's/^.* \([^ ][^ ]*\)$/\1/' -e '1q'`]
+    AC_MSG_RESULT([$makeinfo_version])
+    # Consider only the first two numbers in version number string.
+    makeinfo_version_major=`IFS=.; set x $makeinfo_version; echo ${2}`
+    makeinfo_version_minor=`IFS=.; set x $makeinfo_version; echo ${3}`
+    makeinfo_version_numeric=`
+      expr ${makeinfo_version_major}000 + $makeinfo_version_minor`
+    if test $makeinfo_version_numeric -lt 5000
+    then
+      missing="'makeinfo' is too old."
+      MAKEINFO=
+    fi
+  fi
+
+  if test -n "$missing"
+  then
+    infofile=doc/groff.info
+    test -f $infofile || infofile="$srcdir"/$infofile
+    if test ! -f $infofile \
+     || test "$srcdir"/doc/groff.texi -nt $infofile
+    then
+      AC_MSG_ERROR($missing
+[Get the 'texinfo' package version 5.0 or newer.])
+    fi
+  fi
+  AC_SUBST([MAKEINFO])
+])
+
+# 'makeinfo' and 'texi2dvi' are distributed together, so if the former
+# is too old, the latter is too.
+
+AC_DEFUN([GROFF_PROG_TEXI2DVI], [
+  AC_REQUIRE([GROFF_PROG_MAKEINFO])
+  AC_CHECK_PROG([PROG_TEXI2DVI], [texi2dvi], [texi2dvi], [missing])
+  groff_have_texi2dvi=no
+  if test "$PROG_TEXI2DVI" != missing && test -n "$MAKEINFO"
+  then
+    groff_have_texi2dvi=yes
+  fi
+])
+
+# 'texi2dvi' can be installed without TeX itself, so check for a 'tex'
+# executable independently.
+
+AC_DEFUN([GROFF_USE_TEX_CHECK], [
+  AC_REQUIRE([GROFF_PROG_TEXI2DVI])
+  AC_CHECK_PROG([PROG_TEX], [tex], [found], [missing])
+  groff_use_tex=no
+  test "$PROG_TEX" = found && groff_use_tex=yes
+])
+
+# grohtml needs the following programs to produce images from tbl(1)
+# tables and eqn(1) equations.
+
+dnl Any macro that tests $make_htmldoc should AC_REQUIRE this.
+
+AC_DEFUN([GROFF_CHECK_GROHTML_PROGRAMS], [
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+
+  make_htmldoc=no
+  missing=
+  m4_foreach([groff_prog],
+dnl Keep this list of programs in sync with grohtml test scripts.
+    [[pnmcrop], [pnmcut], [pnmtopng], [pnmtops], [psselect]], [
+      AC_CHECK_PROG(groff_prog, groff_prog, [found], [missing])
+      if test $[]groff_prog = missing
+      then
+        missing="$missing 'groff_prog'"
+      fi
+    ])
+
+  test "$GHOSTSCRIPT" = "missing" && missing="'gs' $missing"
+
+  if test -z "$missing"
+  then
+      make_htmldoc=yes
+  else
+    plural=`set $missing; test $[#] -gt 1 && echo s`
+    oxford=`set $missing; test $[#] -gt 2 && echo ,`
+    missing=`set $missing
+      missing=
+      while test $[#] -gt 0
+      do
+        case $[#] in
+          1) missing="$missing$[1]" ;;
+          2) missing="$missing$[1]$oxford and " ;;
+          *) missing="$missing$[1], " ;;
+        esac
+        shift
+      done
+      echo $missing`
+    verb=`set $missing
+      if test $[#] -gt 1
+      then
+        echo were
+      else
+        echo was
+      fi`
+
+    grohtml_notice="The program$plural $missing $verb not found in \
+\$PATH.
+
+  Consequently, groff's HTML output driver, 'grohtml', will not work
+  properly.  It will not be possible to prepare or install
+  groff-generated documentation in HTML format.
+"
+   fi
+   AC_SUBST([make_htmldoc])
+])
+
+
+AC_DEFUN([GROFF_GROHTML_PROGRAM_NOTICE], [
+  AC_REQUIRE([GROFF_CHECK_GROHTML_PROGRAMS])
+
+  if test "$make_htmldoc" = no
+  then
+    AC_MSG_NOTICE([$grohtml_notice])
+  fi
+])
+
+dnl pdfroff uses awk, and we use it in GROFF_URW_FONTS_CHECK.
+
+AC_DEFUN([GROFF_AWK_NOTICE], [
+  AC_REQUIRE([GROFF_AWK_PATH])
+
+  awk_names=awk
+  if test -n "$ALT_AWK_PROGS"
+  then
+    awk_names="$ALT_AWK_PROGS"
+  fi
+
+  if test "$AWK" = missing
+  then
+    AC_MSG_NOTICE([No awk program was found in \$PATH.
+
+  It was sought under the name(s) "$awk_names".
+    ])
+  fi
+])
+
+AC_DEFUN([GROFF_PDFROFF_DEPENDENCIES_CHECK], [
+  AC_REQUIRE([GROFF_AWK_PATH])
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+
+  use_pdfroff=no
+  pdfroff_missing_deps=
+
+  test "$AWK" = missing && pdfroff_missing_deps="awk"
+
+  if test "$GHOSTSCRIPT" = missing
+  then
+    verb=is
+
+    if test -n "$pdfroff_missing_deps"
+    then
+      pdfroff_missing_deps="$pdfroff_missing_deps and "
+      verb=are
+    fi
+    pdfroff_missing_deps="${pdfroff_missing_deps}Ghostscript $verb"
+  fi
+
+  if test -z "$pdfroff_missing_deps"
+  then
+    use_pdfroff=yes
+  fi
+
+  AC_SUBST([use_pdfroff])
+])
+
+AC_DEFUN([GROFF_GROPDF_DEPENDENCIES_CHECK], [
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+  AC_REQUIRE([GROFF_URW_FONTS_CHECK])
+
+  use_gropdf=no
+  gropdf_missing_deps=
+
+  if test "$GHOSTSCRIPT" != missing \
+    || test "$groff_have_urw_fonts" = yes
+  then
+    use_gropdf=yes
+  fi
+
+  AC_SUBST([use_gropdf])
+])
+
+AC_DEFUN([GROFF_PDFROFF_PROGRAM_NOTICE], [
+  AC_REQUIRE([GROFF_PDFROFF_DEPENDENCIES_CHECK])
+
+  if test "$use_pdfroff" = no
+  then
+    AC_MSG_NOTICE(['pdfroff' will not be functional.
+
+  Because $pdfroff_missing_deps missing, 'pdfroff' will not operate
+  and the 'pdfmark.pdf' document will not be available.
+])
+  fi
+])
+
+AC_DEFUN([GROFF_GROPDF_PROGRAM_NOTICE], [
+  AC_REQUIRE([GROFF_GROPDF_DEPENDENCIES_CHECK])
+
+  if test "$use_gropdf" = no
+  then
+    AC_MSG_NOTICE(['gropdf' will have reduced function.
+
+  Neither Ghostscript nor URW fonts are available; groff documentation
+  thus will not be available in PDF.
+
+  'gropdf' will be able to handle only documents using the standard PDF
+  base 14 fonts, plus the 'EURO' font groff supplies, and font embedding
+  with its '-e' option (accessed via the 'groff' command with the option
+  '-P -e') will not be possible.
+])
+  fi
+])
+
+# Make URW font directory configurable.
+
+AC_DEFUN([GROFF_URW_FONTS_PATH], [
+  AC_ARG_WITH([urw-fonts-dir],
+    [AS_HELP_STRING([--with-urw-fonts-dir=DIR],
+      [search for URW PostScript Type 1 fonts in DIR])],
+    [urwfontsdir="$withval"])
+])
+
+# Check for availability of URW fonts in the directory specified by the
+# user (see GROFF_URW_FONTS_PATH above).  We do NOT search the path of
+# directories built into Ghostscript because those fonts lack the
+# corresponding AFM files we need to generate groff font description
+# files; see afmtodit(1).  Ghostscript's own fonts are treated as the
+# "default foundry" and we already provide descriptions of them in
+# font/devpdf (along with groff's EURO font).
+
+AC_DEFUN([GROFF_URW_FONTS_CHECK], [
+  AC_REQUIRE([GROFF_URW_FONTS_PATH])
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+  groff_have_urw_fonts=no
+  AC_MSG_CHECKING([for URW fonts in Type 1/PFB format])
+
+dnl Keep this list in sync with font/devpdf/Foundry.in.
+  _list_paths="\
+    /usr/share/fonts/type1/gsfonts/ \
+    /usr/share/fonts/default/Type1/ \
+    /usr/share/fonts/default/Type1/adobestd35/ \
+    /usr/share/fonts/type1/urw-base35/ \
+    /opt/local/share/fonts/urw-fonts/ \
+    /usr/local/share/fonts/ghostscript/"
+
+  if test -n "$urwfontsdir"
+  then
+    _list_paths="$urwfontsdir"
+  fi
+
+dnl Keep this list of font file names in sync with the corresponding
+dnl entry in font/devpdf/util/BuildFoundries.pl.
+  for k in $_list_paths
+  do
+    for _font_file in \
+      URWGothic-Book \
+      URWGothic-Book.t1 \
+      URWGothic-Book.pfb \
+      URWGothicL-Book.pfb \
+      a010013l.pfb
+    do
+      if test -f $k/$_font_file
+      then
+        AC_MSG_RESULT([found in $k])
+        groff_have_urw_fonts=yes
+        urwfontsdir=$k
+        break 2
+      fi
+    done
+  done
+
+  if test $groff_have_urw_fonts = no
+  then
+    AC_MSG_RESULT([none found])
+    urwfontsdir=
+  fi
+
+  AC_SUBST([groff_have_urw_fonts])
+  AC_SUBST(urwfontsdir)
+])
+
+AC_DEFUN([GROFF_URW_FONTS_NOTICE], [
+  if test "$groff_have_urw_fonts" = no
+  then
+    gs_verbiage=
+    if test "$GHOSTSCRIPT" != missing
+    then
+      gs_verbiage=' as well as the search path shown by the
+  "'"$GHOSTSCRIPT"' -h" command (if available)'
+    fi
+    AC_MSG_NOTICE([URW fonts in Type 1/PFB format were not found.
+
+  groff font description files for the URW fonts, used by the 'gropdf'
+  output driver, will not be available.  Use and embedding of fonts from
+  the 'U' foundry in PDF documents generated by groff will not be
+  possible.
+
+  You can obtain the URW base 35 fonts from their GitHub project.  As of
+  this writing (2023-02-15), you can find them in the 'fonts' directory
+  of the following archives (choose one).
+
+    https://github.com/ArtifexSoftware/urw-base35-fonts/archive/refs/
+      tags/20200910.zip
+    https://github.com/ArtifexSoftware/urw-base35-fonts/archive/refs/
+      tags/20200910.tar.gz
+
+  You may wish to check for a newer release.
+
+    https://github.com/ArtifexSoftware/urw-base35-fonts/releases
+
+  'gropdf' looks for these fonts in several directories specified in
+  font/devpdf/Foundry.in$gs_verbiage.
+
+  You will need to "make distclean" and re-run the 'configure' script
+  after installing the URW fonts.
+
+  Alternatively, you can pass the option '--with-urw-fonts-dir=DIR'
+  to 'configure' to look for them in the directory DIR you specify.
+  If found, the 'U' foundry will be available via the '-y' option to
+  'gropdf' (accessed via the 'groff' command with the option '-P -y').
+    ])
+  fi
+])
+
+
+# Check whether the pnm tools accept the -quiet option.
+
+dnl Any macro that tests $pnmtools_quiet should AC_REQUIRE this.
+
+AC_DEFUN([GROFF_PNMTOOLS_CAN_BE_QUIET], [
+  AC_REQUIRE([GROFF_CHECK_GROHTML_PROGRAMS])
+
+  pnmtools_quiet=
+
+  if test "$make_htmldoc" = yes
+  then
+    AC_MSG_CHECKING([whether PNM tools accept the '-quiet' option])
+    if echo P2 2 2 255 0 1 2 0 | pnmtops -quiet > /dev/null 2>&1
+    then
+      AC_MSG_RESULT([yes])
+      pnmtools_quiet=-quiet
+    else
+      AC_MSG_RESULT([no])
+    fi
+  fi
+  AC_SUBST([pnmtools_quiet])
+])
+
+
+# Check whether pnmtops can handle the -nosetpage option.
+#
+# We require this both for grohtml operation and generation of
+# doc/gnu.eps from repository builds.
+
+AC_DEFUN([GROFF_PNMTOPS_NOSETPAGE], [
+  AC_REQUIRE([GROFF_PNMTOOLS_CAN_BE_QUIET])
+
+  pnmtops_nosetpage="pnmtops $pnmtools_quiet"
+  AC_MSG_CHECKING([whether pnmtops accepts the '-nosetpage' option])
+  if echo P2 2 2 255 0 1 2 0 | pnmtops -nosetpage > /dev/null 2>&1
+  then
+    AC_MSG_RESULT([yes])
+    pnmtops_nosetpage="pnmtops $pnmtools_quiet -nosetpage"
+  else
+    AC_MSG_RESULT([no])
+  fi
+  AC_SUBST([pnmtops_nosetpage])
+])
+
+
+# Check location of 'gs'; allow '--with-gs=PROG' option to override.
+
+dnl Any macro that tests $GHOSTSCRIPT should AC_REQUIRE this.
+
+AC_DEFUN([GROFF_GHOSTSCRIPT_PATH],
+  [AC_REQUIRE([GROFF_GHOSTSCRIPT_PREFS])
+   AC_ARG_WITH([gs],
+     [AS_HELP_STRING([--with-gs=PROG],
+       [actual [/path/]name of ghostscript executable])],
+     [GHOSTSCRIPT=$withval],
+     [AC_CHECK_TOOLS(GHOSTSCRIPT, [$ALT_GHOSTSCRIPT_PROGS], [missing])])
+   test "$GHOSTSCRIPT" = no && GHOSTSCRIPT=missing])
+
+# Preferences for choice of 'gs' program...
+# (allow --with-alt-gs="LIST" to override).
+
+AC_DEFUN([GROFF_GHOSTSCRIPT_PREFS],
+  [AC_ARG_WITH([alt-gs],
+    [AS_HELP_STRING([--with-alt-gs=LIST],
+      [alternative names for ghostscript executable])],
+    [ALT_GHOSTSCRIPT_PROGS="$withval"],
+    [ALT_GHOSTSCRIPT_PROGS="gs gswin32c gsos2"])
+   AC_SUBST([ALT_GHOSTSCRIPT_PROGS])])
+
+AC_DEFUN([GROFF_GHOSTSCRIPT_AVAILABILITY_NOTICE], [
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+
+  gs_names=gs
+  if test -n "$ALT_GHOSTSCRIPT_PROGS"
+  then
+    gs_names="$ALT_GHOSTSCRIPT_PROGS"
+  fi
+
+  if test "$GHOSTSCRIPT" = missing
+  then
+    AC_MSG_NOTICE([No Ghostscript program was found in \$PATH.
+
+  It was sought under the name(s) "$gs_names".
+
+  groff documentation will not be available in HTML.
+
+  'grohtml' will have reduced function, being unable to produce
+  documents using the 'tbl' preprocessor.
+    ])
+  fi
+])
+
+# Ghostscript version check.  Versions 9.00 <= x < 9.54 suffer from a
+# rendering glitch that affects the AT&T troff (and groff) special
+# character \(lh; see
+#   <https://bugs.ghostscript.com/show_bug.cgi?id=703187>.
+
+AC_DEFUN([GROFF_GHOSTSCRIPT_VERSION_CHECK], [
+  AC_REQUIRE([GROFF_GHOSTSCRIPT_PATH])
+
+  if test "$GHOSTSCRIPT" != missing
+  then
+    AC_MSG_CHECKING([for gs version with good left sidebearing handling])
+    ghostscript_notice=
+    ghostscript_version_good=
+    ghostscript_v_string=`"$GHOSTSCRIPT" -v | sed 1q`
+    # Get first word.
+    ghostscript_words=`echo "$ghostscript_v_string" | cut -d\  -f1-`
+
+    # If the first word is "GPL", discard it.
+    if expr "$ghostscript_words" : "GPL" > /dev/null
+    then
+      ghostscript_words=`echo "$ghostscript_words" | cut -d\  -f2-`
+    fi
+
+    # Only do a version check if the program calls itself Ghostscript.
+    if expr "$ghostscript_words" : "Ghostscript" > /dev/null
+    then
+      ghostscript_version_good=no
+      ghostscript_version=`echo "$ghostscript_words" | cut -d\  -f2`
+      ghostscript_major=`echo "$ghostscript_version" | cut -d. -f1`
+      ghostscript_minor=`echo "$ghostscript_version" | cut -d. -f2`
+
+      if test "$ghostscript_major" -lt 9
+      then
+        ghostscript_version_good=yes
+      elif test "$ghostscript_major" -ge 10
+      then
+        ghostscript_version_good=yes
+      elif test "$ghostscript_minor" -ge 54
+      then
+        ghostscript_version_good=yes
+      fi
+    fi
+
+    if test "$ghostscript_version_good" = yes
+    then
+      ghostscript_version="$ghostscript_version (good)"
+    elif test "$ghostscript_version_good" = no
+    then
+      ghostscript_version="$ghostscript_version (buggy)"
+      ghostscript_notice="Buggy version of Ghostscript detected."
+    else
+      ghostscript_notice="Unable to determine version of Ghostscript."
+    fi
+
+    if test -n "$ghostscript_version"
+    then
+      AC_MSG_RESULT([got $ghostscript_version])
+    else
+      AC_MSG_RESULT([unable to determine])
+    fi
+  fi
+])
+
+AC_DEFUN([GROFF_GHOSTSCRIPT_VERSION_NOTICE], [
+  if test -n "$ghostscript_notice"
+  then
+    AC_MSG_NOTICE([$ghostscript_notice
+
+  Ghostscript versions 9.00 <= x < 9.54 suffer from a rendering glitch
+  that affects the AT&T troff (and groff) special character '\(lh'; see
+  <https://bugs.ghostscript.com/show_bug.cgi?id=703187>.  If your
+  version of Ghostscript has not been patched to fix this problem, you
+  may need to work around it in groff documents you render for the
+  PostScript (and, for tbl(1) tables, HTML) output devices.
+  ])
+  fi
+])
+
+# Check location of 'awk'; allow '--with-awk=PROG' option to override.
+
+AC_DEFUN([GROFF_AWK_PATH],
+  [AC_REQUIRE([GROFF_AWK_PREFS])
+   AC_ARG_WITH([awk],
+     [AS_HELP_STRING([--with-awk=PROG],
+       [actual [/path/]name of awk executable])],
+     [AWK=$withval],
+     [AC_CHECK_TOOLS(AWK, [$ALT_AWK_PROGS], [missing])])
+   test "$AWK" = no && AWK=missing])
+
+
+# Preferences for choice of 'awk' program; allow --with-alt-awk="LIST"
+# to override.
+
+AC_DEFUN([GROFF_AWK_PREFS],
+  [AC_ARG_WITH([alt-awk],
+    [AS_HELP_STRING([--with-alt-awk=LIST],
+      [alternative names for awk executable])],
+    [ALT_AWK_PROGS="$withval"],
+    [ALT_AWK_PROGS="gawk mawk nawk awk"])
+   AC_SUBST([ALT_AWK_PROGS])])
+
+
+# GROFF_CSH_HACK(if hack present, if not present)
+
+AC_DEFUN([GROFF_CSH_HACK],
+  [AC_MSG_CHECKING([for csh hash hack])
+
+cat <<EOF >conftest.sh
+#! /bin/sh
+true || exit 0
+export PATH || exit 0
+exit 1
+EOF
+
+   chmod +x conftest.sh
+   if echo ./conftest.sh | (csh >/dev/null 2>&1) >/dev/null 2>&1; then
+     AC_MSG_RESULT([yes])
+     $1
+   else
+     AC_MSG_RESULT([no])
+     $2
+   fi
+   rm -f conftest.sh])
+
+
+# From udodo!hans@relay.NL.net (Hans Zuidam)
+
+AC_DEFUN([GROFF_ISC_SYSV3],
+  [AC_MSG_CHECKING([for ISC 3.x or 4.x])
+   if grep ['[34]\.'] /usr/options/cb.name >/dev/null 2>&1
+   then
+     AC_MSG_RESULT([yes])
+     AC_DEFINE([_SYSV3], [1], [Define if you have ISC 3.x or 4.x.])
+   else
+     AC_MSG_RESULT([no])
+   fi])
+
+AC_DEFUN([GROFF_POSIX],
+  [AC_MSG_CHECKING([whether -D_POSIX_SOURCE is necessary])
+   AC_LANG_PUSH([C++])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <stdio.h>
+extern "C" { void fileno(int); }
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([_POSIX_SOURCE], [1],
+	[Define if -D_POSIX_SOURCE is necessary.])],
+     [AC_MSG_RESULT([no])])
+   AC_LANG_POP([C++])])
+
+
+# srand() of SunOS 4.1.3 has return type int instead of void
+
+AC_DEFUN([GROFF_SRAND],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([for return type of srand])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <stdlib.h>
+extern "C" { void srand(unsigned int); }
+
+       ]])
+     ],
+     [AC_MSG_RESULT([void])
+      AC_DEFINE([RET_TYPE_SRAND_IS_VOID], [1],
+	[Define if srand() returns void not int.])],
+     [AC_MSG_RESULT([int])])
+   AC_LANG_POP([C++])])
+
+
+# In April 2005, autoconf's AC_TYPE_SIGNAL is still broken.
+
+AC_DEFUN([GROFF_TYPE_SIGNAL],
+  [AC_MSG_CHECKING([for return type of signal handlers])
+   for groff_declaration in \
+     'extern "C" void (*signal (int, void (*)(int)))(int);' \
+     'extern "C" void (*signal (int, void (*)(int)) throw ())(int);' \
+     'void (*signal ()) ();' 
+   do
+     AC_COMPILE_IFELSE([
+	 AC_LANG_PROGRAM([[
+
+#include <sys/types.h>
+#include <signal.h>
+#ifdef signal
+# undef signal
+#endif
+$groff_declaration
+
+	 ]],
+	 [[
+
+int i;
+
+	 ]])
+       ],
+       [break],
+       [continue])
+   done
+
+   if test -n "$groff_declaration"; then
+     AC_MSG_RESULT([void])
+     AC_DEFINE([RETSIGTYPE], [void],
+       [Define as the return type of signal handlers
+	('int' or 'void').])
+   else
+     AC_MSG_RESULT([int])
+     AC_DEFINE([RETSIGTYPE], [int],
+       [Define as the return type of signal handlers
+	('int' or 'void').])
+   fi])
+
+
+AC_DEFUN([GROFF_SYS_NERR],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([for sys_nerr in <errno.h>, <stdio.h>, or <stdlib.h>])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+       ]],
+       [[
+
+int k;
+k = sys_nerr;
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_SYS_NERR], [1],
+	[Define if you have sys_nerr in <errno.h>, <stdio.h>, or <stdio.h>.])],
+     [AC_MSG_RESULT([no])])
+   AC_LANG_POP([C++])])
+
+AC_DEFUN([GROFF_SYS_ERRLIST],
+  [AC_MSG_CHECKING([for sys_errlist[] in <errno.h>, <stdio.h>, or <stdlib.h>])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+       ]],
+       [[
+
+int k;
+k = (int)sys_errlist[0];
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_SYS_ERRLIST], [1],
+	[Define if you have sys_errlist in <errno.h>, <stdio.h>, or <stdlib.h>.])],
+     [AC_MSG_RESULT([no])])])
+
+AC_DEFUN([GROFF_OSFCN_H],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([C++ <osfcn.h>])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <osfcn.h>
+
+       ]],
+       [[
+
+read(0, 0, 0);
+open(0, 0);
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_CC_OSFCN_H], [1],
+	[Define if you have a C++ <osfcn.h>.])],
+     [AC_MSG_RESULT([no])])
+   AC_LANG_POP([C++])])
+
+
+AC_DEFUN([GROFF_LIMITS_H],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([C++ <limits.h>])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <limits.h>
+
+       ]],
+       [[
+
+int x = INT_MIN;
+int y = INT_MAX;
+int z = UCHAR_MAX;
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_CC_LIMITS_H], [1],
+	[Define if you have a C++ <limits.h>.])],
+     [AC_MSG_RESULT([no])])
+   AC_LANG_POP([C++])])
+
+AC_DEFUN([GROFF_TIME_T],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([for declaration of time_t])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <time.h>
+
+       ]],
+       [[
+
+time_t t = time(0);
+struct tm *p = localtime(&t);
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])],
+     [AC_MSG_RESULT([no])
+      AC_DEFINE([LONG_FOR_TIME_T], [1],
+	[Define if localtime() takes a long * not a time_t *.])])
+   AC_LANG_POP([C++])])
+
+AC_DEFUN([GROFF_STRUCT_EXCEPTION],
+  [AC_MSG_CHECKING([struct exception])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <math.h>
+
+       ]],
+       [[
+
+struct exception e;
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_STRUCT_EXCEPTION], [1],
+	[Define if <math.h> defines struct exception.])],
+     [AC_MSG_RESULT([no])])])
+
+AC_DEFUN([GROFF_ARRAY_DELETE],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([whether ISO C++98 array deletion syntax is supported])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM(, [[
+
+char *p = new char[5];
+delete [] p;
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])],
+     [AC_MSG_RESULT([no])
+      AC_MSG_ERROR([an ISO C++98-conformant compiler is required])])
+   AC_LANG_POP([C++])])
+
+AC_DEFUN([GROFF_TRADITIONAL_CPP],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([whether C preprocessor uses pre-ISO C90 syntax])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#define name2(a, b) a/**/b
+
+       ]],
+       [[
+
+int name2(foo, bar);
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_MSG_ERROR([an ISO C90-conformant C preprocessor is required])],
+     [AC_MSG_RESULT([no])])
+   AC_LANG_POP([C++])])
+
+AC_DEFUN([GROFF_WCOREFLAG],
+  [AC_MSG_CHECKING([w_coredump])
+   AC_RUN_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+       ]],
+       [[
+
+main()
+{
+#ifdef WCOREFLAG
+  exit(1);
+#else
+  int i = 0;
+  ((union wait *)&i)->w_coredump = 1;
+  exit(i != 0200);
+#endif
+}
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE(WCOREFLAG, 0200,
+	[Define if the 0200 bit of the status returned by wait() indicates
+	 whether a core image was produced for a process that was terminated
+	 by a signal.])],
+     [AC_MSG_RESULT([no])],
+     [AC_MSG_RESULT([no])])])
+
+
+AC_DEFUN([GROFF_BROKEN_SPOOLER_FLAGS],
+  [AC_MSG_CHECKING([default value for grops -b option])
+   test -n "$BROKEN_SPOOLER_FLAGS" || BROKEN_SPOOLER_FLAGS=0
+   AC_MSG_RESULT([$BROKEN_SPOOLER_FLAGS])
+   AC_SUBST([BROKEN_SPOOLER_FLAGS])])
+
+
+AC_DEFUN([GROFF_PAGE], [
+  AC_MSG_CHECKING([default paper format])
+  groff_prefix=$prefix
+  test "$prefix" = NONE && groff_prefix=$ac_default_prefix
+  if test -z "$PAGE" && test -r /etc/papersize
+  then
+    sedexpr='s/#.*//;s/[ \t]\+/ /;s/ \+$//;s/^ \+//;/^$/d;p'
+    PAGE=`sed -n "$sedexpr" /etc/papersize`
+  fi
+  if test -z "$PAGE"
+  then
+    descfile=
+    if test -r "$groff_prefix"/share/groff/font/devps/DESC
+    then
+      descfile=$groff_prefix/share/groff/font/devps/DESC
+    elif test -r "$groff_prefix"/lib/groff/font/devps/DESC
+    then
+      descfile=$groff_prefix/lib/groff/font/devps/DESC
+    else
+      for f in "$groff_prefix"/share/groff/*/font/devps/DESC
+      do
+	if test -r "$f"
+	then
+	  descfile=$f
+	  break
+	fi
+      done
+    fi
+
+    if test -n "$descfile"
+    then
+      if grep -q ['^paperlength[	 ]\+841890'] "$descfile"
+      then
+	PAGE=A4
+      elif grep -q ['^papersize[	 ]\+[aA]4'] "$descfile"
+      then
+	PAGE=A4
+      fi
+    fi
+  fi
+
+  if test -z "$PAGE"
+  then
+    domains=
+    if test -r /etc/resolv.conf
+    then
+      sedexpr='s/#.*//;s/[ \t]\+/ /;s/ \+$//;s/^ \+//;/^$/d;
+/^\(domain\|search\)/!d;s/\(domain\|search\) //;p'
+      domains=`sed -n "$sedexpr" /etc/resolv.conf`
+    fi
+    if test -z "$domains"
+    then
+      domains=`(domainname) 2>/dev/null | tr -d '+'`
+      if test -z "$domains" || test "$domains" = '(none)'
+      then
+        domains=`(hostname) 2>/dev/null | grep '\.'`
+      fi
+    fi
+    # resolv.conf's "search" directive might return multiple domains.
+    # If any top-level domain is two letters and it's not 'us' or 'ca',
+    # assume the system uses A4 paper.
+    for d in $domains
+    do
+      case "$d" in
+      [*.[Uu][Ss]|*.[Cc][Aa])]
+        ;;
+      [*.[A-Za-z][A-Za-z])]
+        PAGE=A4 ;;
+      esac
+    done
+  fi
+
+  test -n "$PAGE" || PAGE=letter
+  AC_MSG_RESULT([$PAGE])
+  AC_SUBST([PAGE])
+])
+
+
+AC_DEFUN([GROFF_CXX_CHECK],
+  [AC_REQUIRE([AC_PROG_CXX])
+   AC_LANG_PUSH([C++])
+   if test "$cross_compiling" = no; then
+     AC_MSG_CHECKING([that C++ compiler can compile simple program])
+   fi
+   AC_RUN_IFELSE([
+       AC_LANG_SOURCE([[
+
+int main() {
+  return 0;
+}
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])],
+     [AC_MSG_RESULT([no])
+      AC_MSG_ERROR([a working C++ compiler is required])],
+     [:])
+
+   if test "$cross_compiling" = no; then
+     AC_MSG_CHECKING([that C++ static constructors and destructors are called])
+   fi
+   AC_RUN_IFELSE([
+       AC_LANG_SOURCE([[
+
+extern "C" {
+  void _exit(int);
+}
+
+int i;
+struct A {
+  char dummy;
+  A() { i = 1; }
+  ~A() { if (i == 1) _exit(0); }
+};
+
+A a;
+
+int main()
+{
+  return 1;
+}
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])],
+     [AC_MSG_RESULT([no])
+      AC_MSG_ERROR([a working C++ compiler is required])],
+     [:])
+
+   AC_MSG_CHECKING([that header files support C++])
+   AC_LINK_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <stdio.h>
+
+       ]],
+       [[
+
+fopen(0, 0);
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])],
+     [AC_MSG_RESULT([no])
+      AC_MSG_ERROR([header files do not support C++
+		   (if you are using a version of gcc/g++ earlier than 2.5,
+		   you should install libg++)])])
+   AC_LANG_POP([C++])])
+
+
+AC_DEFUN([GROFF_TMAC],
+  [AC_MSG_CHECKING([for prefix of system macro packages])
+   sys_tmac_prefix=
+   sys_tmac_file_prefix=
+   for d in /usr/share/lib/tmac /usr/lib/tmac; do
+     for t in "" tmac.; do
+       for m in an s m; do
+	 f=$d/$t$m
+	 if test -z "$sys_tmac_prefix" \
+	    && test -f $f \
+	    && grep '^\.if' $f >/dev/null 2>&1; then
+	   sys_tmac_prefix=$d/$t
+	   sys_tmac_file_prefix=$t
+	 fi
+       done
+     done
+   done
+   sys_tmac_prefix_result=none
+   test -z "$sys_tmac_prefix" \
+	|| sys_tmac_prefix_result="$sys_tmac_prefix"
+   AC_MSG_RESULT([$sys_tmac_prefix_result])
+   AC_SUBST([sys_tmac_prefix])
+
+   AC_MSG_CHECKING([which system macro packages should be made available])
+   tmac_wrap=
+   if test "$sys_tmac_file_prefix" = tmac.; then
+     for f in $sys_tmac_prefix*; do
+       suff=`echo $f | sed -e "s;$sys_tmac_prefix;;"`
+       case "$suff" in
+       e)
+	 ;;
+       *)
+	 grep "Copyright.*Free Software Foundation" $f >/dev/null \
+	      || tmac_wrap="$tmac_wrap $suff" ;;
+       esac
+     done
+   elif test -n "$sys_tmac_prefix"; then
+     files=`echo $sys_tmac_prefix*`
+     grep "\\.so" $files >conftest.sol
+     for f in $files; do
+       case "$f" in
+       ${sys_tmac_prefix}e)
+	 ;;
+       *.me)
+	 ;;
+       */ms.*)
+	 ;;
+       *)
+	 b=`basename $f`
+	 if grep "\\.so.*/$b\$" conftest.sol >/dev/null \
+	    || grep -l "Copyright.*Free Software Foundation" $f >/dev/null; then
+	   :
+	 else
+	   suff=`echo $f | sed -e "s;$sys_tmac_prefix;;"`
+	   case "$suff" in
+	   tmac.*)
+	     ;;
+	   *)
+	     tmac_wrap="$tmac_wrap $suff" ;;
+	   esac
+	 fi
+       esac
+     done
+     rm -f conftest.sol
+   fi
+   tmac_wrap_result="none found"
+   test -z "$tmac_wrap" || tmac_wrap_result="$tmac_wrap"
+   AC_MSG_RESULT([$tmac_wrap_result])
+   AC_SUBST([tmac_wrap])])
+
+
+# Searching if a non-GNU Troff is installed.  The built-in register
+# \n[.g] is always 1 in GNU Troff.
+AC_DEFUN([GROFF_G], [
+  g=
+  AC_MSG_CHECKING([for existing troff installation])
+  if test "`(echo .tm '|n(.g' | tr '|' '\\\\' | troff -z -i 2>&1) \
+    2>/dev/null`" = 0
+  then
+    AC_MSG_RESULT([yes])
+    g=g
+  else
+    AC_MSG_RESULT([no])
+  fi
+  AC_SUBST([g])
+])
+
+
+# Controllable groff compatibility wrappers for vendor-provided macro sets
+#
+#   Background
+#
+#     groff's configure script checks for a non-GNU system troff implementation
+#     in GROFF_G above, and uses this to rename programs that would conflict
+#     with the system *roff implementation. On such systems, groff's version of
+#     troff is installed as gtroff, groff's version of nroff is installed as
+#     gnroff, and so forth. See the ENVIRONMENT section of groff(1)'s manual
+#     page for the entry on GROFF_COMMAND_PREFIX, and the SEE ALSO section for
+#     details. The implementation of this can be found in "We use Automake's
+#     Uniform Naming Scheme" in Makefile.am, and its use of NAMEPREFIX.
+#
+#     groff's configure script also checks for vendor-provided macro sets in
+#     GROFF_TMAC above, which sets 'sys_tmac_prefix' to the location of any
+#     vendor-provided macro sets. The script then determines if any of these
+#     vendor-provided macro sets are non-GNU implementations. A space-separated
+#     list of macro sets requiring compatibility wrappers is stored in
+#     'tmac_wrap'.
+#
+#     If 'tmac_wrap' is a non-empty list, the make infrastructure will build
+#     groff compatibility wrappers in the 'tmac' directory for each mentioned
+#     macro set. These wrappers enable compatibility mode (.cp 1) and include
+#     (.so <filepath>) the vendor implementation of that macro set. The 'an'
+#     wrapper gets special treatment, by including the 'andoc.tmac' macro set,
+#     before loading the vendor implementation.
+#
+#     In groff version 1.22.3 and prior, if 'tmac_wrap' is a non-empty list at
+#     installation time (make install), the groff compatibility wrappers are
+#     installed in '<prefix>/lib/groff/site-tmac' directory (technically
+#     'systemtmacdir' in Makefile.am) as the base macro set name (example:
+#     an.tmac), and the groff implementation of these macro sets are installed
+#     with a 'g' prefix in the '<prefix>/share/groff/<version>/tmac' directory
+#     (example: gan.tmac).
+#
+#     If your system has these compatibility wrappers installed, then the
+#     command 'groff -man ...' (as an example) uses your vendor's 'an' macro
+#     set in compatibility mode, while the command 'groff -mgan ...' uses the
+#     groff implementation of the 'an' macro set.
+#
+#     With groff being the principal (but not the only) full-featured *roff
+#     implementation in use today, and most FLOSS Unix-like Operating Systems
+#     using groff as their *roff implementation, the automatic implementation
+#     of compatibility wrappers on systems having their own macro sets needs to
+#     be revisited. Most FLOSS software is now developed on systems having no
+#     other *roff implementation, so manual pages (for example) are developed
+#     and proofread on systems using groff's implementation of the 'an' macro
+#     set.
+#
+#     On systems with their own macro sets (especially 'an'), documents can be
+#     rendered incorrectly from the document author's point of view, when
+#     these compatibility mode wrappers are used. groff's own manual pages are
+#     the perfect case in point, with most not showing the principal usage line
+#     of a command, due to the use of .SY/.OP/.YS macros to display such lines.
+#
+#   Updating groff's use of compatibility mode wrappers
+#
+#     Given the above, on systems with their own (non-GNU) macro sets, groff's
+#     AUTOMATIC installation of these generated vendor compatibility wrappers
+#     as the principal implementation of a macro set for groff(1) users may not
+#     be desirable, especially if the users are principally using groff(1) to
+#     format FLOSS manual pages.
+#
+#     The '--with-compatibility-wrappers=<value>' option to 'configure' gives
+#     these systems control over the default macro set implementation in use
+#     when using the groff family of tools.
+#
+#     The supported values of the '--with-compatibility-wrappers=<value>'
+#     option are:
+#       'check'  [default] Check if system has vendor-provided non-GNU
+#                implementation of any *roff macro set. Based on that use the
+#                'yes' or 'no' value for '--with-compatibility-wrappers'. This
+#                effectively emulates prior groff releases' implementation.
+#       'yes'    Install the vendor compatibility wrappers as groff's default
+#                implementation of these macro sets. This is compatible with
+#                groff implementations up to and including version 1.22.3.
+#                Direct use of the 'yes' option is discouraged, as it will
+#                abort the configure process if no vendor-provided non-GNU
+#                macro set implementations exists.
+#       'no'     Do not install any vendor compatibility wrappers. Use the
+#                groff implementation of all macro sets as the default.
+#       'manual' Install the vendor compatibility wrappers as '<macro>-os.tmac'
+#                in the same directory as 'yes' option ('systemtmacdir').
+#                groff users can access the vendor-provided macro set via the
+#                '-m<macro>-os' option on the command line of a tool from the
+#                groff family. The naming of the option value reflects that now
+#                a manual step must be taken to use the vendor-provided
+#                implementation of the macro set. This option can safely be
+#                used on systems without vendor-provided non-GNU macro set
+#                implementations to allow for cross-platform build
+#                instructions.
+#
+
+AC_DEFUN([GROFF_WITH_COMPATIBILITY_WRAPPERS],
+  [AC_ARG_WITH([compatibility-wrappers],
+    [AS_HELP_STRING([--with-compatibility-wrappers[={check|manual|no|yes}]],
+      [choose whether and how groff compatibility wrappers for \
+       vendor-provided non-GNU macro packages are installed. \
+       'check' searches for such packages, and behaves as if 'yes' or \
+       'no' were given, accordingly. \
+       'yes' generates compatibility wrappers for the vendor-provided \
+       packages to allow their use with groff and related tools. \
+       The compatibility wrappers are installed using the
+       vendor-provided names, while their groff implementations are \
+       installed with a 'g' prefix. \
+       Use of the latter thus requires options of the form
+       '-mg<package>' (example: -mgan). \
+       'no' installs only the groff implementations.
+       'manual' generates compatibility wrappers for the \
+       vendor-provided packages as '<macro>-os'. \
+       Use of the latter thus requires options of the form
+       '-m<macro>-os' option (example: -man-os).])],
+    [compatibility_wrappers="$withval"],
+    [compatibility_wrappers="check"])
+
+    if    test "$compatibility_wrappers" != check \
+       && test "$compatibility_wrappers" != yes   \
+       && test "$compatibility_wrappers" != no    \
+       && test "$compatibility_wrappers" != manual
+    then
+         AC_MSG_WARN([Invalid '--with-compatibility-wrappers' argument: '$compatibility_wrappers' - assuming 'check' requested.])
+         compatibility_wrappers="check"
+    fi
+
+    if test -z "$tmac_wrap"
+    then
+        # No Operating System Macro Sets Present
+        if   test "$compatibility_wrappers" = check
+        then
+            compatibility_wrappers="no"
+        elif test "$compatibility_wrappers" = yes
+        then
+            AC_MSG_ERROR([No non-GNU macro sets found - cannot create and install compatibility wrappers])
+        elif test "$compatibility_wrappers" = no
+        then
+            : # No action required
+        elif test "$compatibility_wrappers" = manual
+        then
+            # 'manual' allows quiet conversion to 'no' to support
+            # cross-platform build instructions
+            compatibility_wrappers="no"
+        fi
+    else
+        # One or more Operating System Macro Sets Present
+        if   test "$compatibility_wrappers" = check
+        then
+            compatibility_wrappers="yes"
+        fi
+    fi
+
+    # Now compatibility_wrappers can only be yes, no or manual
+    AC_SUBST([compatibility_wrappers])
+  ])
+
+# We need the path to install-sh to be absolute.
+
+AC_DEFUN([GROFF_INSTALL_SH],
+  [AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT])
+   ac_dir=`cd $ac_aux_dir; pwd`
+   ac_install_sh="$ac_dir/install-sh -c"])
+
+
+# Test whether install-info is available.
+
+AC_DEFUN([GROFF_INSTALL_INFO],
+  [AC_CHECK_PROGS([INSTALL_INFO], [install-info], [:])])
+
+
+# At least one Unix system, Apple Macintosh Rhapsody 5.5,
+# does not have -lm ...
+
+AC_DEFUN([GROFF_LIBM],
+  [AC_CHECK_LIB([m], [sin], [LIBM=-lm])
+   AC_SUBST([LIBM])])
+
+
+# ... while the MinGW implementation of GCC for Microsoft Win32
+# does not seem to have -lc.
+
+AC_DEFUN([GROFF_LIBC],
+  [AC_CHECK_LIB([c], [main], [LIBC=-lc])
+   AC_SUBST([LIBC])])
+
+
+# Check for EBCDIC -- stolen from the OS390 Unix LYNX port
+
+AC_DEFUN([GROFF_EBCDIC],
+  [AC_MSG_CHECKING([whether character set is EBCDIC])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+/* Treat any failure as ASCII for compatibility with existing art.
+   Use compile-time rather than run-time tests for cross-compiler
+   tolerance. */
+#if '0' != 240
+make an error "Character set is not EBCDIC"
+#endif
+
+       ]])
+     ],
+     [groff_cv_ebcdic="yes"
+      TTYDEVDIRS="font/devcp1047"
+      AC_MSG_RESULT([yes])
+      AC_DEFINE(IS_EBCDIC_HOST, 1,
+	[Define if the host's encoding is EBCDIC.])],
+     [groff_cv_ebcdic="no"
+     TTYDEVDIRS="font/devascii font/devlatin1"
+     OTHERDEVDIRS="font/devlj4 font/devlbp"
+     AC_MSG_RESULT([no])])
+   AC_SUBST([TTYDEVDIRS])
+   AC_SUBST([OTHERDEVDIRS])])
+
+
+# Check for OS/390 Unix.  We test for EBCDIC also -- the Linux port (with
+# gcc) to OS/390 uses ASCII internally.
+
+AC_DEFUN([GROFF_OS390],
+  [if test "$groff_cv_ebcdic" = "yes"; then
+     AC_MSG_CHECKING([for OS/390 Unix])
+     case `uname` in
+     OS/390)
+       CFLAGS="$CFLAGS -D_ALL_SOURCE"
+       AC_MSG_RESULT([yes]) ;;
+     *)
+       AC_MSG_RESULT([no]) ;;
+     esac
+   fi])
+
+
+# Check whether Windows scripts like 'afmtodit.cmd' should be installed.
+
+AC_DEFUN([GROFF_CMD_FILES],
+  [AC_MSG_CHECKING([whether to install .cmd wrapper scripts for Windows])
+   case "$host_os" in
+   *mingw*)
+     make_winscripts=winscripts
+     AC_MSG_RESULT([yes]) ;;
+   *)
+     make_winscripts=
+     AC_MSG_RESULT([no]) ;;
+   esac
+   AC_SUBST([make_winscripts])])
+
+
+# Check whether we need a declaration for a function.
+#
+# Stolen from GNU bfd.
+
+AC_DEFUN([GROFF_NEED_DECLARATION],
+  [AC_MSG_CHECKING([whether $1 must be declared])
+   AC_LANG_PUSH([C++])
+   AC_CACHE_VAL([groff_cv_decl_needed_$1],
+     [AC_COMPILE_IFELSE([
+	  AC_LANG_PROGRAM([[
+
+#include <stdio.h>
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_MATH_H
+#include <math.h>
+#endif
+
+	  ]],
+	  [[
+
+#ifndef $1
+  char *p = (char *) $1;
+#endif
+
+	  ]])
+      ],
+      [groff_cv_decl_needed_$1=no],
+      [groff_cv_decl_needed_$1=yes])])
+   AC_MSG_RESULT([$groff_cv_decl_needed_$1])
+   if test $groff_cv_decl_needed_$1 = yes; then
+     AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), [1],
+       [Define if your C++ doesn't declare ]$1[().])
+   fi
+   AC_LANG_POP([C++])])
+
+
+# If mkstemp() isn't available, use our own mkstemp.cpp file.
+
+AC_DEFUN([GROFF_MKSTEMP],
+  [AC_MSG_CHECKING([for mkstemp])
+   AC_LANG_PUSH([C++])
+   AC_LIBSOURCE([mkstemp.cpp])
+   AC_LINK_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <stdlib.h>
+#include <unistd.h>
+int (*f) (char *);
+
+       ]],
+       [[
+
+f = mkstemp;
+
+       ]])
+     ],
+     [AC_MSG_RESULT([yes])
+      AC_DEFINE([HAVE_MKSTEMP], [1], [Define if you have mkstemp().])],
+     [AC_MSG_RESULT([no])
+      _AC_LIBOBJ([mkstemp])])
+   AC_LANG_POP([C++])])
+
+
+# Test whether <inttypes.h> exists, doesn't clash with <sys/types.h>,
+# and declares uintmax_t.  Taken from the fileutils package.
+
+AC_DEFUN([GROFF_INTTYPES_H],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([C++ <inttypes.h>])
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+
+#include <sys/types.h>
+#include <inttypes.h>
+
+       ]],
+       [[
+
+uintmax_t i = (uintmax_t)-1;
+
+       ]])
+     ],
+     [groff_cv_header_inttypes_h=yes
+      AC_DEFINE([HAVE_CC_INTTYPES_H], [1],
+	[Define if you have a C++ <inttypes.h>.])],
+     [groff_cv_header_inttypes_h=no])
+   AC_MSG_RESULT([$groff_cv_header_inttypes_h])
+   AC_LANG_POP([C++])])
+
+
+# Test for working 'unsigned long long'.  Taken from the fileutils package.
+
+AC_DEFUN([GROFF_UNSIGNED_LONG_LONG],
+  [AC_LANG_PUSH([C++])
+   AC_MSG_CHECKING([for unsigned long long])
+   AC_LINK_IFELSE([
+       AC_LANG_PROGRAM([[
+
+unsigned long long ull = 1;
+int i = 63;
+unsigned long long ullmax = (unsigned long long)-1;
+
+       ]],
+       [[
+
+return ull << i | ull >> i | ullmax / ull | ullmax % ull;
+
+       ]])
+     ],
+     [groff_cv_type_unsigned_long_long=yes],
+     [groff_cv_type_unsigned_long_long=no])
+   AC_MSG_RESULT([$groff_cv_type_unsigned_long_long])
+   AC_LANG_POP([C++])])
+
+
+# Define uintmax_t to 'unsigned long' or 'unsigned long long'
+# if <inttypes.h> does not exist.  Taken from the fileutils package.
+
+AC_DEFUN([GROFF_UINTMAX_T],
+  [AC_REQUIRE([GROFF_INTTYPES_H])
+   if test $groff_cv_header_inttypes_h = no; then
+     AC_REQUIRE([GROFF_UNSIGNED_LONG_LONG])
+     test $groff_cv_type_unsigned_long_long = yes \
+	  && ac_type='unsigned long long' \
+	  || ac_type='unsigned long'
+     AC_DEFINE_UNQUOTED([uintmax_t], [$ac_type],
+       [Define uintmax_t to 'unsigned long' or 'unsigned long long' if
+	<inttypes.h> does not exist.])
+   fi])
+
+
+# Identify PATH_SEPARATOR character to use in GROFF_FONT_PATH and
+# GROFF_TMAC_PATH which is appropriate for the target system (POSIX=':',
+# MS-DOS/Win32=';').
+#
+# The logic to resolve this test is already encapsulated in
+# '$srcdir/src/include/nonposix.h'.
+
+AC_DEFUN([GROFF_TARGET_PATH_SEPARATOR],
+  [AC_MSG_CHECKING([separator character to use in groff search paths])
+   cp "$srcdir"/src/include/nonposix.h conftest.h
+   AC_COMPILE_IFELSE([
+       AC_LANG_PROGRAM([[
+	
+#include <ctype.h>
+#include "conftest.h"
+
+       ]],
+       [[
+
+#if PATH_SEP_CHAR == ';'
+make an error "Path separator is ';'"
+#endif
+
+       ]])
+     ],
+     [GROFF_PATH_SEPARATOR=":"],
+     [GROFF_PATH_SEPARATOR=";"])
+   AC_MSG_RESULT([$GROFF_PATH_SEPARATOR])
+   AC_SUBST(GROFF_PATH_SEPARATOR)])
+
+
+# Check for X11.
+
+AC_DEFUN([GROFF_X11], [
+  AC_REQUIRE([AC_PATH_XTRA])
+  groff_no_x=$no_x
+  if test -z "$groff_no_x"
+  then
+    OLDCFLAGS=$CFLAGS
+    OLDLDFLAGS=$LDFLAGS
+    OLDLIBS=$LIBS
+    CFLAGS="$CFLAGS $X_CFLAGS"
+    LDFLAGS="$LDFLAGS $X_LIBS"
+    LIBS="$LIBS $X_PRE_LIBS -lX11 $X_EXTRA_LIBS"
+
+    LIBS="$LIBS -lXaw"
+    AC_MSG_CHECKING([for Xaw library and header files])
+    AC_LINK_IFELSE([
+      AC_LANG_PROGRAM([[
+
+#include <X11/Intrinsic.h>
+#include <X11/Xaw/Simple.h>
+
+        ]],
+        [])
+      ],
+      [AC_MSG_RESULT([yes])],
+      [AC_MSG_RESULT([no])
+      groff_no_x=yes])
+
+    LIBS="$LIBS -lXmu"
+    AC_MSG_CHECKING([for Xmu library and header files])
+    AC_LINK_IFELSE([
+      AC_LANG_PROGRAM([[
+
+#include <X11/Intrinsic.h>
+#include <X11/Xmu/Converters.h>
+
+        ]],
+        [])
+      ],
+      [AC_MSG_RESULT([yes])],
+      [AC_MSG_RESULT([no])
+      groff_no_x=yes])
+
+    CFLAGS=$OLDCFLAGS
+    LDFLAGS=$OLDLDFLAGS
+    LIBS=$OLDLIBS
+  fi
+
+  if ! test "$groff_no_x" = yes
+  then
+    XDEVDIRS="font/devX75 font/devX75-12 font/devX100 font/devX100-12"
+    XPROGDIRS="src/devices/xditview src/utils/xtotroff"
+    XLIBDIRS="src/libs/libxutil"
+  fi
+
+  AC_SUBST([XDEVDIRS])
+  AC_SUBST([XPROGDIRS])
+  AC_SUBST([XLIBDIRS])
+])
+
+
+# Interpret the '--with-appdefdir' command-line option.
+
+dnl Don't quote AS_HELP_STRING!
+dnl
+dnl TODO: Include the computed default in the RHS of the help string.
+AC_DEFUN([GROFF_APPDEFDIR_OPTION], [
+  AC_ARG_WITH([appdefdir],
+    AS_HELP_STRING([--with-appdefdir=DIR],
+      [place X11 application defaults files in DIR]))
+])
+
+
+# Get a default value for the application defaults directory.
+#
+# We ignore the 'XAPPLRES' and 'XUSERFILESEARCHPATH' environment
+# variables.
+#
+# By default if --with-appdefdir is not used, we will install the
+# gxditview application defaults in $prefix/lib/X11/app-defaults.
+#
+# Note that if --with-appdefdir was passed to 'configure', no prefix is
+# added to 'appdefdir'.
+
+AC_DEFUN([GROFF_APPDEFDIR_DEFAULT],
+  [if test -z "$groff_no_x"; then
+     if test -z "$with_appdefdir"; then
+       if test "$prefix" = NONE; then
+         appdefdir=$ac_default_prefix/lib/X11/app-defaults
+       else
+         appdefdir=$prefix/lib/X11/app-defaults
+       fi
+     else
+       appdefdir=$with_appdefdir
+     fi
+   fi
+   AC_SUBST([appdefdir])])
+
+# Emit warning if --with-appdefdir hasn't been used.
+
+AC_DEFUN([GROFF_APPDEFDIR_NOTICE],
+  [if test -z "$groff_no_x"; then
+     if test -z "$with_appdefdir"; then
+       AC_MSG_NOTICE([Default X11 application defaults directory \
+assumed.
+
+  The application defaults files for gxditview (GXditview and
+  GXditview-color) will be installed in the following directory.
+
+    $appdefdir
+
+  To install elsewhere, say, '/etc/X11/app-defaults', add
+  '--with-appdefdir=/etc/X11/app-defaults' to the configure script
+  command-line options and rerun it (the 'prefix' value has no effect on
+  a --with-appdefdir option).
+
+  If the gxditview app-defaults are installed in a directory that is not
+  one of the default X11 directories for this purpose (common defaults
+  are /usr/lib/X11/app-defaults, /usr/share/X11/app-defaults, and
+  /etc/X11/app-defaults), you will have to set the environment variable
+  XFILESEARCHPATH to this path.  More details can be found in the X(7)
+  manual page, or in the document "X Toolkit Intrinsics - C Language
+  Interface manual".
+       ])
+     fi
+   fi])
+
+
+AC_DEFUN([GROFF_LIBPROGRAMDIR_DEFAULT],
+  libprogramdir=$libdir/groff
+  AC_SUBST([libprogramdir]))
+
+
+AC_DEFUN([GROFF_GLILYPONDDIR_DEFAULT],
+  glilypond_dir=$libprogramdir/glilypond
+  AC_SUBST([glilypond_dir]))
+
+
+AC_DEFUN([GROFF_GPINYINDIR_DEFAULT],
+  gpinyin_dir=$libprogramdir/gpinyin
+  AC_SUBST([gpinyin_dir]))
+
+
+AC_DEFUN([GROFF_REFERDIR_DEFAULT],
+  referdir=$libprogramdir/refer
+  AC_SUBST([referdir]))
+
+# Generation of doc/gnu.eps requires xpmtoppm.
+
+AC_DEFUN([GROFF_PROG_XPMTOPPM],
+  [AC_CHECK_PROG([XPMTOPPM], [xpmtoppm], [found], [missing])])
+
+# Check for make built-in variable RM.
+
+AC_DEFUN([GROFF_MAKE_DEFINES_RM], [
+  AC_MSG_CHECKING(whether make defines 'RM')
+  make=make
+  if test -n "$MAKE"
+  then
+    make=$MAKE
+  fi
+  cat <<EOF > test_make_rm.mk
+all:
+	@if test -n "\$(RM)"; \
+	then \
+	   echo yes; \
+	else \
+	   echo no; \
+	fi
+EOF
+  groff_make_defines_rm=`"$make" -sf test_make_rm.mk`
+  AC_MSG_RESULT([$groff_make_defines_rm])
+  rm -f test_make_rm.mk
+])
+
+# Check if diff has option -D, for gdiffmk. If not, check if gdiff is
+# available on the system and make the same test. If either diff or
+# gdiff is working, it is set to DIFF_PROG.  If -D option is not
+# available, DIFF_PROG is left to diff (gdiffmk will report a
+# problem).
+
+AC_DEFUN([GROFF_DIFF_D],
+  [AC_MSG_CHECKING(for a diff program that supports option -D)
+  groff_has_diff_d_option=no
+  DIFF_PROG=diff
+  diff -Dx /dev/null /dev/null >/dev/null 2>&1 && groff_has_diff_d_option=yes
+  if test "$groff_has_diff_d_option" = no; then
+    AC_CHECK_PROGS([GDIFF], [gdiff])
+    if test -n "$GDIFF"; then
+      "$GDIFF" -Dx /dev/null /dev/null >/dev/null 2>&1 && groff_has_diff_d_option=yes
+      if test "$groff_has_diff_d_option" = yes; then
+        DIFF_PROG="$GDIFF"
+      fi
+    fi
+  fi
+  AC_MSG_RESULT([$groff_has_diff_d_option])
+  AC_SUBST([DIFF_PROG])])
+
+# Check if 'test' supports the option -ef.
+
+AC_DEFUN([GROFF_HAVE_TEST_EF_OPTION],
+  [AC_MSG_CHECKING(whether test supports option -ef)
+  HAVE_TEST_EF_OPTION=no
+  test /dev/null -ef /dev/null > /dev/null 2>&1 && HAVE_TEST_EF_OPTION=yes
+  AC_MSG_RESULT([$HAVE_TEST_EF_OPTION])
+  AC_SUBST([HAVE_TEST_EF_OPTION])])
+
+# gdiffmk will attempt to use bash (for option -ef of 'test'). If bash
+# is not available it will use /bin/sh.
+
+AC_DEFUN([GROFF_BASH],
+  [AC_PATH_PROGS([BASH_PROG], [bash], [no])
+  if test "$BASH_PROG" = no; then
+     BASH_PROG=/bin/sh
+  fi
+  AC_SUBST([BASH_PROG])])
+
+# Search for uchardet library used by preconv.
+
+AC_DEFUN([GROFF_UCHARDET], [
+  AC_ARG_WITH([uchardet],
+    AS_HELP_STRING([--with-uchardet={auto|no|yes}],
+      [build 'preconv' against uchardet library to automatically \
+detect input file encoding]))
+    AS_IF([test "$with_uchardet" != no],
+      [PKG_CHECK_MODULES([UCHARDET],
+        [uchardet >= 0.0.1],
+        [AC_DEFINE([HAVE_UCHARDET], [1],
+          [uchardet library availability])
+        groff_have_uchardet=yes], [
+          if test "$with_uchardet" = yes
+          then
+            AC_MSG_FAILURE([could not find uchardet library])
+          fi
+          groff_have_uchardet=no])],
+      [groff_have_uchardet=no])
+])
+
+AC_DEFUN([GROFF_UCHARDET_NOTICE], [
+  if test "$groff_have_uchardet" = no && test "$with_uchardet" != no
+  then
+    AC_MSG_NOTICE([The uchardet library was not found.
+
+  The 'preconv' preprocessor program will be unable to attempt automatic
+  inference of an input file's character encoding.  See the preconv(1)
+  man page.
+  ])
+  fi
+])
+
+
+AC_DEFUN([GROFF_USE_GROFF_ALLOCATOR], [
+  AC_ARG_ENABLE([groff-allocator],
+    [AS_HELP_STRING([--enable-groff-allocator], [enable libgroff's \
+allocator for C++ new/delete])],
+    [test "$enableval" = yes && groff_use_own_allocator=yes],
+    [groff_use_own_allocator=no])
+])
diff --git a/m4/iconv.m4 b/m4/iconv.m4
new file mode 100644
index 0000000..ec7cd0a
--- /dev/null
+++ b/m4/iconv.m4
@@ -0,0 +1,271 @@
+# iconv.m4 serial 19 (gettext-0.18.2)
+dnl Copyright (C) 2000-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+AC_DEFUN([AM_ICONV_LINKFLAGS_BODY],
+[
+  dnl Prerequisites of AC_LIB_LINKFLAGS_BODY.
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  AC_REQUIRE([AC_LIB_RPATH])
+
+  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
+  dnl accordingly.
+  AC_LIB_LINKFLAGS_BODY([iconv])
+])
+
+AC_DEFUN([AM_ICONV_LINK],
+[
+  dnl Some systems have iconv in libc, some have it in libiconv (OSF/1 and
+  dnl those with the standalone portable GNU libiconv installed).
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
+  dnl accordingly.
+  AC_REQUIRE([AM_ICONV_LINKFLAGS_BODY])
+
+  dnl Add $INCICONV to CPPFLAGS before performing the following checks,
+  dnl because if the user has installed libiconv and not disabled its use
+  dnl via --without-libiconv-prefix, he wants to use it. The first
+  dnl AC_LINK_IFELSE will then fail, the second AC_LINK_IFELSE will succeed.
+  am_save_CPPFLAGS="$CPPFLAGS"
+  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INCICONV])
+
+  AC_CACHE_CHECK([for iconv], [am_cv_func_iconv], [
+    am_cv_func_iconv="no, consider installing GNU libiconv"
+    am_cv_lib_iconv=no
+    AC_LINK_IFELSE(
+      [AC_LANG_PROGRAM(
+         [[
+#include <stdlib.h>
+#include <iconv.h>
+         ]],
+         [[iconv_t cd = iconv_open("","");
+           iconv(cd,NULL,NULL,NULL,NULL);
+           iconv_close(cd);]])],
+      [am_cv_func_iconv=yes])
+    if test "$am_cv_func_iconv" != yes; then
+      am_save_LIBS="$LIBS"
+      LIBS="$LIBS $LIBICONV"
+      AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[
+#include <stdlib.h>
+#include <iconv.h>
+           ]],
+           [[iconv_t cd = iconv_open("","");
+             iconv(cd,NULL,NULL,NULL,NULL);
+             iconv_close(cd);]])],
+        [am_cv_lib_iconv=yes]
+        [am_cv_func_iconv=yes])
+      LIBS="$am_save_LIBS"
+    fi
+  ])
+  if test "$am_cv_func_iconv" = yes; then
+    AC_CACHE_CHECK([for working iconv], [am_cv_func_iconv_works], [
+      dnl This tests against bugs in AIX 5.1, AIX 6.1..7.1, HP-UX 11.11,
+      dnl Solaris 10.
+      am_save_LIBS="$LIBS"
+      if test $am_cv_lib_iconv = yes; then
+        LIBS="$LIBS $LIBICONV"
+      fi
+      am_cv_func_iconv_works=no
+      for ac_iconv_const in '' 'const'; do
+        AC_RUN_IFELSE(
+          [AC_LANG_PROGRAM(
+             [[
+#include <iconv.h>
+#include <string.h>
+
+#ifndef ICONV_CONST
+# define ICONV_CONST $ac_iconv_const
+#endif
+             ]],
+             [[int result = 0;
+  /* Test against AIX 5.1 bug: Failures are not distinguishable from successful
+     returns.  */
+  {
+    iconv_t cd_utf8_to_88591 = iconv_open ("ISO8859-1", "UTF-8");
+    if (cd_utf8_to_88591 != (iconv_t)(-1))
+      {
+        static ICONV_CONST char input[] = "\342\202\254"; /* EURO SIGN */
+        char buf[10];
+        ICONV_CONST char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_utf8_to_88591,
+                            &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res == 0)
+          result |= 1;
+        iconv_close (cd_utf8_to_88591);
+      }
+  }
+  /* Test against Solaris 10 bug: Failures are not distinguishable from
+     successful returns.  */
+  {
+    iconv_t cd_ascii_to_88591 = iconv_open ("ISO8859-1", "646");
+    if (cd_ascii_to_88591 != (iconv_t)(-1))
+      {
+        static ICONV_CONST char input[] = "\263";
+        char buf[10];
+        ICONV_CONST char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_ascii_to_88591,
+                            &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res == 0)
+          result |= 2;
+        iconv_close (cd_ascii_to_88591);
+      }
+  }
+  /* Test against AIX 6.1..7.1 bug: Buffer overrun.  */
+  {
+    iconv_t cd_88591_to_utf8 = iconv_open ("UTF-8", "ISO-8859-1");
+    if (cd_88591_to_utf8 != (iconv_t)(-1))
+      {
+        static ICONV_CONST char input[] = "\304";
+        static char buf[2] = { (char)0xDE, (char)0xAD };
+        ICONV_CONST char *inptr = input;
+        size_t inbytesleft = 1;
+        char *outptr = buf;
+        size_t outbytesleft = 1;
+        size_t res = iconv (cd_88591_to_utf8,
+                            &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res != (size_t)(-1) || outptr - buf > 1 || buf[1] != (char)0xAD)
+          result |= 4;
+        iconv_close (cd_88591_to_utf8);
+      }
+  }
+#if 0 /* This bug could be worked around by the caller.  */
+  /* Test against HP-UX 11.11 bug: Positive return value instead of 0.  */
+  {
+    iconv_t cd_88591_to_utf8 = iconv_open ("utf8", "iso88591");
+    if (cd_88591_to_utf8 != (iconv_t)(-1))
+      {
+        static ICONV_CONST char input[] = "\304rger mit b\366sen B\374bchen ohne Augenma\337";
+        char buf[50];
+        ICONV_CONST char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_88591_to_utf8,
+                            &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if ((int)res > 0)
+          result |= 8;
+        iconv_close (cd_88591_to_utf8);
+      }
+  }
+#endif
+  /* Test against HP-UX 11.11 bug: No converter from EUC-JP to UTF-8 is
+     provided.  */
+  if (/* Try standardized names.  */
+      iconv_open ("UTF-8", "EUC-JP") == (iconv_t)(-1)
+      /* Try IRIX, OSF/1 names.  */
+      && iconv_open ("UTF-8", "eucJP") == (iconv_t)(-1)
+      /* Try AIX names.  */
+      && iconv_open ("UTF-8", "IBM-eucJP") == (iconv_t)(-1)
+      /* Try HP-UX names.  */
+      && iconv_open ("utf8", "eucJP") == (iconv_t)(-1))
+    result |= 16;
+  return result;
+]])],
+          [am_cv_func_iconv_works=yes], ,
+          [case "$host_os" in
+             aix* | hpux*) am_cv_func_iconv_works="guessing no" ;;
+             *)            am_cv_func_iconv_works="guessing yes" ;;
+           esac])
+        test "$am_cv_func_iconv_works" = no || break
+      done
+      LIBS="$am_save_LIBS"
+    ])
+    case "$am_cv_func_iconv_works" in
+      *no) am_func_iconv=no am_cv_lib_iconv=no ;;
+      *)   am_func_iconv=yes ;;
+    esac
+  else
+    am_func_iconv=no am_cv_lib_iconv=no
+  fi
+  if test "$am_func_iconv" = yes; then
+    AC_DEFINE([HAVE_ICONV], [1],
+      [Define if you have the iconv() function and it works.])
+  fi
+  if test "$am_cv_lib_iconv" = yes; then
+    AC_MSG_CHECKING([how to link with libiconv])
+    AC_MSG_RESULT([$LIBICONV])
+  else
+    dnl If $LIBICONV didn't lead to a usable library, we don't need $INCICONV
+    dnl either.
+    CPPFLAGS="$am_save_CPPFLAGS"
+    LIBICONV=
+    LTLIBICONV=
+  fi
+  AC_SUBST([LIBICONV])
+  AC_SUBST([LTLIBICONV])
+])
+
+dnl Define AM_ICONV using AC_DEFUN_ONCE for Autoconf >= 2.64, in order to
+dnl avoid warnings like
+dnl "warning: AC_REQUIRE: 'AM_ICONV' was expanded before it was required".
+dnl This is tricky because of the way 'aclocal' is implemented:
+dnl - It requires defining an auxiliary macro whose name ends in AC_DEFUN.
+dnl   Otherwise aclocal's initial scan pass would miss the macro definition.
+dnl - It requires a line break inside the AC_DEFUN_ONCE and AC_DEFUN expansions.
+dnl   Otherwise aclocal would emit many "Use of uninitialized value $1"
+dnl   warnings.
+m4_define([gl_iconv_AC_DEFUN],
+  m4_version_prereq([2.64],
+    [[AC_DEFUN_ONCE(
+        [$1], [$2])]],
+    [m4_ifdef([gl_00GNULIB],
+       [[AC_DEFUN_ONCE(
+           [$1], [$2])]],
+       [[AC_DEFUN(
+           [$1], [$2])]])]))
+gl_iconv_AC_DEFUN([AM_ICONV],
+[
+  AM_ICONV_LINK
+  if test "$am_cv_func_iconv" = yes; then
+    AC_MSG_CHECKING([for iconv declaration])
+    AC_CACHE_VAL([am_cv_proto_iconv], [
+      AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[
+#include <stdlib.h>
+#include <iconv.h>
+extern
+#ifdef __cplusplus
+"C"
+#endif
+#if defined(__STDC__) || defined(_MSC_VER) || defined(__cplusplus)
+size_t iconv (iconv_t cd, char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);
+#else
+size_t iconv();
+#endif
+           ]],
+           [[]])],
+        [am_cv_proto_iconv_arg1=""],
+        [am_cv_proto_iconv_arg1="const"])
+      am_cv_proto_iconv="extern size_t iconv (iconv_t cd, $am_cv_proto_iconv_arg1 char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);"])
+    am_cv_proto_iconv=`echo "[$]am_cv_proto_iconv" | tr -s ' ' | sed -e 's/( /(/'`
+    AC_MSG_RESULT([
+         $am_cv_proto_iconv])
+    AC_DEFINE_UNQUOTED([ICONV_CONST], [$am_cv_proto_iconv_arg1],
+      [Define as const if the declaration of iconv() needs const.])
+    dnl Also substitute ICONV_CONST in the gnulib generated <iconv.h>.
+    m4_ifdef([gl_ICONV_H_DEFAULTS],
+      [AC_REQUIRE([gl_ICONV_H_DEFAULTS])
+       if test -n "$am_cv_proto_iconv_arg1"; then
+         ICONV_CONST="const"
+       fi
+      ])
+  fi
+])
diff --git a/m4/lib-ld.m4 b/m4/lib-ld.m4
new file mode 100644
index 0000000..d3eb0fc
--- /dev/null
+++ b/m4/lib-ld.m4
@@ -0,0 +1,119 @@
+# lib-ld.m4 serial 6
+dnl Copyright (C) 1996-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Subroutines of libtool.m4,
+dnl with replacements s/_*LT_PATH/AC_LIB_PROG/ and s/lt_/acl_/ to avoid
+dnl collision with libtool.m4.
+
+dnl From libtool-2.4. Sets the variable with_gnu_ld to yes or no.
+AC_DEFUN([AC_LIB_PROG_LD_GNU],
+[AC_CACHE_CHECK([if the linker ($LD) is GNU ld], [acl_cv_prog_gnu_ld],
+[# I'd rather use --version here, but apparently some GNU lds only accept -v.
+case `$LD -v 2>&1 </dev/null` in
+*GNU* | *'with BFD'*)
+  acl_cv_prog_gnu_ld=yes
+  ;;
+*)
+  acl_cv_prog_gnu_ld=no
+  ;;
+esac])
+with_gnu_ld=$acl_cv_prog_gnu_ld
+])
+
+dnl From libtool-2.4. Sets the variable LD.
+AC_DEFUN([AC_LIB_PROG_LD],
+[AC_REQUIRE([AC_PROG_CC])dnl
+AC_REQUIRE([AC_CANONICAL_HOST])dnl
+
+AC_ARG_WITH([gnu-ld],
+    [AS_HELP_STRING([--with-gnu-ld],
+        [assume the C compiler uses GNU ld [default=no]])],
+    [test "$withval" = no || with_gnu_ld=yes],
+    [with_gnu_ld=no])dnl
+
+# Prepare PATH_SEPARATOR.
+# The user is always right.
+if test "${PATH_SEPARATOR+set}" != set; then
+  # Determine PATH_SEPARATOR by trying to find /bin/sh in a PATH which
+  # contains only /bin. Note that ksh looks also at the FPATH variable,
+  # so we have to set that as well for the test.
+  PATH_SEPARATOR=:
+  (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+    && { (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+           || PATH_SEPARATOR=';'
+       }
+fi
+
+ac_prog=ld
+if test "$GCC" = yes; then
+  # Check if gcc -print-prog-name=ld gives a path.
+  AC_MSG_CHECKING([for ld used by $CC])
+  case $host in
+  *-*-mingw*)
+    # gcc leaves a trailing carriage return which upsets mingw
+    ac_prog=`($CC -print-prog-name=ld) 2>&5 | tr -d '\015'` ;;
+  *)
+    ac_prog=`($CC -print-prog-name=ld) 2>&5` ;;
+  esac
+  case $ac_prog in
+    # Accept absolute paths.
+    [[\\/]]* | ?:[[\\/]]*)
+      re_direlt='/[[^/]][[^/]]*/\.\./'
+      # Canonicalize the pathname of ld
+      ac_prog=`echo "$ac_prog"| sed 's%\\\\%/%g'`
+      while echo "$ac_prog" | grep "$re_direlt" > /dev/null 2>&1; do
+        ac_prog=`echo $ac_prog| sed "s%$re_direlt%/%"`
+      done
+      test -z "$LD" && LD="$ac_prog"
+      ;;
+  "")
+    # If it fails, then pretend we aren't using GCC.
+    ac_prog=ld
+    ;;
+  *)
+    # If it is relative, then search for the first ld in PATH.
+    with_gnu_ld=unknown
+    ;;
+  esac
+elif test "$with_gnu_ld" = yes; then
+  AC_MSG_CHECKING([for GNU ld])
+else
+  AC_MSG_CHECKING([for non-GNU ld])
+fi
+AC_CACHE_VAL([acl_cv_path_LD],
+[if test -z "$LD"; then
+  acl_save_ifs="$IFS"; IFS=$PATH_SEPARATOR
+  for ac_dir in $PATH; do
+    IFS="$acl_save_ifs"
+    test -z "$ac_dir" && ac_dir=.
+    if test -f "$ac_dir/$ac_prog" || test -f "$ac_dir/$ac_prog$ac_exeext"; then
+      acl_cv_path_LD="$ac_dir/$ac_prog"
+      # Check to see if the program is GNU ld.  I'd rather use --version,
+      # but apparently some variants of GNU ld only accept -v.
+      # Break only if it was the GNU/non-GNU ld that we prefer.
+      case `"$acl_cv_path_LD" -v 2>&1 </dev/null` in
+      *GNU* | *'with BFD'*)
+        test "$with_gnu_ld" != no && break
+        ;;
+      *)
+        test "$with_gnu_ld" != yes && break
+        ;;
+      esac
+    fi
+  done
+  IFS="$acl_save_ifs"
+else
+  acl_cv_path_LD="$LD" # Let the user override the test with a path.
+fi])
+LD="$acl_cv_path_LD"
+if test -n "$LD"; then
+  AC_MSG_RESULT([$LD])
+else
+  AC_MSG_RESULT([no])
+fi
+test -z "$LD" && AC_MSG_ERROR([no acceptable ld found in \$PATH])
+AC_LIB_PROG_LD_GNU
+])
diff --git a/m4/lib-link.m4 b/m4/lib-link.m4
new file mode 100644
index 0000000..4aa359a
--- /dev/null
+++ b/m4/lib-link.m4
@@ -0,0 +1,777 @@
+# lib-link.m4 serial 26 (gettext-0.18.2)
+dnl Copyright (C) 2001-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+AC_PREREQ([2.54])
+
+dnl AC_LIB_LINKFLAGS(name [, dependencies]) searches for libname and
+dnl the libraries corresponding to explicit and implicit dependencies.
+dnl Sets and AC_SUBSTs the LIB${NAME} and LTLIB${NAME} variables and
+dnl augments the CPPFLAGS variable.
+dnl Sets and AC_SUBSTs the LIB${NAME}_PREFIX variable to nonempty if libname
+dnl was found in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
+AC_DEFUN([AC_LIB_LINKFLAGS],
+[
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  AC_REQUIRE([AC_LIB_RPATH])
+  pushdef([Name],[m4_translit([$1],[./+-], [____])])
+  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
+                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+  AC_CACHE_CHECK([how to link with lib[]$1], [ac_cv_lib[]Name[]_libs], [
+    AC_LIB_LINKFLAGS_BODY([$1], [$2])
+    ac_cv_lib[]Name[]_libs="$LIB[]NAME"
+    ac_cv_lib[]Name[]_ltlibs="$LTLIB[]NAME"
+    ac_cv_lib[]Name[]_cppflags="$INC[]NAME"
+    ac_cv_lib[]Name[]_prefix="$LIB[]NAME[]_PREFIX"
+  ])
+  LIB[]NAME="$ac_cv_lib[]Name[]_libs"
+  LTLIB[]NAME="$ac_cv_lib[]Name[]_ltlibs"
+  INC[]NAME="$ac_cv_lib[]Name[]_cppflags"
+  LIB[]NAME[]_PREFIX="$ac_cv_lib[]Name[]_prefix"
+  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
+  AC_SUBST([LIB]NAME)
+  AC_SUBST([LTLIB]NAME)
+  AC_SUBST([LIB]NAME[_PREFIX])
+  dnl Also set HAVE_LIB[]NAME so that AC_LIB_HAVE_LINKFLAGS can reuse the
+  dnl results of this search when this library appears as a dependency.
+  HAVE_LIB[]NAME=yes
+  popdef([NAME])
+  popdef([Name])
+])
+
+dnl AC_LIB_HAVE_LINKFLAGS(name, dependencies, includes, testcode, [missing-message])
+dnl searches for libname and the libraries corresponding to explicit and
+dnl implicit dependencies, together with the specified include files and
+dnl the ability to compile and link the specified testcode. The missing-message
+dnl defaults to 'no' and may contain additional hints for the user.
+dnl If found, it sets and AC_SUBSTs HAVE_LIB${NAME}=yes and the LIB${NAME}
+dnl and LTLIB${NAME} variables and augments the CPPFLAGS variable, and
+dnl #defines HAVE_LIB${NAME} to 1. Otherwise, it sets and AC_SUBSTs
+dnl HAVE_LIB${NAME}=no and LIB${NAME} and LTLIB${NAME} to empty.
+dnl Sets and AC_SUBSTs the LIB${NAME}_PREFIX variable to nonempty if libname
+dnl was found in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
+AC_DEFUN([AC_LIB_HAVE_LINKFLAGS],
+[
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  AC_REQUIRE([AC_LIB_RPATH])
+  pushdef([Name],[m4_translit([$1],[./+-], [____])])
+  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
+                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+
+  dnl Search for lib[]Name and define LIB[]NAME, LTLIB[]NAME and INC[]NAME
+  dnl accordingly.
+  AC_LIB_LINKFLAGS_BODY([$1], [$2])
+
+  dnl Add $INC[]NAME to CPPFLAGS before performing the following checks,
+  dnl because if the user has installed lib[]Name and not disabled its use
+  dnl via --without-lib[]Name-prefix, he wants to use it.
+  ac_save_CPPFLAGS="$CPPFLAGS"
+  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
+
+  AC_CACHE_CHECK([for lib[]$1], [ac_cv_lib[]Name], [
+    ac_save_LIBS="$LIBS"
+    dnl If $LIB[]NAME contains some -l options, add it to the end of LIBS,
+    dnl because these -l options might require -L options that are present in
+    dnl LIBS. -l options benefit only from the -L options listed before it.
+    dnl Otherwise, add it to the front of LIBS, because it may be a static
+    dnl library that depends on another static library that is present in LIBS.
+    dnl Static libraries benefit only from the static libraries listed after
+    dnl it.
+    case " $LIB[]NAME" in
+      *" -l"*) LIBS="$LIBS $LIB[]NAME" ;;
+      *)       LIBS="$LIB[]NAME $LIBS" ;;
+    esac
+    AC_LINK_IFELSE(
+      [AC_LANG_PROGRAM([[$3]], [[$4]])],
+      [ac_cv_lib[]Name=yes],
+      [ac_cv_lib[]Name='m4_if([$5], [], [no], [[$5]])'])
+    LIBS="$ac_save_LIBS"
+  ])
+  if test "$ac_cv_lib[]Name" = yes; then
+    HAVE_LIB[]NAME=yes
+    AC_DEFINE([HAVE_LIB]NAME, 1, [Define if you have the lib][$1 library.])
+    AC_MSG_CHECKING([how to link with lib[]$1])
+    AC_MSG_RESULT([$LIB[]NAME])
+  else
+    HAVE_LIB[]NAME=no
+    dnl If $LIB[]NAME didn't lead to a usable library, we don't need
+    dnl $INC[]NAME either.
+    CPPFLAGS="$ac_save_CPPFLAGS"
+    LIB[]NAME=
+    LTLIB[]NAME=
+    LIB[]NAME[]_PREFIX=
+  fi
+  AC_SUBST([HAVE_LIB]NAME)
+  AC_SUBST([LIB]NAME)
+  AC_SUBST([LTLIB]NAME)
+  AC_SUBST([LIB]NAME[_PREFIX])
+  popdef([NAME])
+  popdef([Name])
+])
+
+dnl Determine the platform dependent parameters needed to use rpath:
+dnl   acl_libext,
+dnl   acl_shlibext,
+dnl   acl_libname_spec,
+dnl   acl_library_names_spec,
+dnl   acl_hardcode_libdir_flag_spec,
+dnl   acl_hardcode_libdir_separator,
+dnl   acl_hardcode_direct,
+dnl   acl_hardcode_minus_L.
+AC_DEFUN([AC_LIB_RPATH],
+[
+  dnl Tell automake >= 1.10 to complain if config.rpath is missing.
+  m4_ifdef([AC_REQUIRE_AUX_FILE], [AC_REQUIRE_AUX_FILE([config.rpath])])
+  AC_REQUIRE([AC_PROG_CC])                dnl we use $CC, $GCC, $LDFLAGS
+  AC_REQUIRE([AC_LIB_PROG_LD])            dnl we use $LD, $with_gnu_ld
+  AC_REQUIRE([AC_CANONICAL_HOST])         dnl we use $host
+  AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
+  AC_CACHE_CHECK([for shared library run path origin], [acl_cv_rpath], [
+    CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
+    ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
+    . ./conftest.sh
+    rm -f ./conftest.sh
+    acl_cv_rpath=done
+  ])
+  wl="$acl_cv_wl"
+  acl_libext="$acl_cv_libext"
+  acl_shlibext="$acl_cv_shlibext"
+  acl_libname_spec="$acl_cv_libname_spec"
+  acl_library_names_spec="$acl_cv_library_names_spec"
+  acl_hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
+  acl_hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
+  acl_hardcode_direct="$acl_cv_hardcode_direct"
+  acl_hardcode_minus_L="$acl_cv_hardcode_minus_L"
+  dnl Determine whether the user wants rpath handling at all.
+  AC_ARG_ENABLE([rpath],
+    [  --disable-rpath         do not hardcode runtime library paths],
+    :, enable_rpath=yes)
+])
+
+dnl AC_LIB_FROMPACKAGE(name, package)
+dnl declares that libname comes from the given package. The configure file
+dnl will then not have a --with-libname-prefix option but a
+dnl --with-package-prefix option. Several libraries can come from the same
+dnl package. This declaration must occur before an AC_LIB_LINKFLAGS or similar
+dnl macro call that searches for libname.
+AC_DEFUN([AC_LIB_FROMPACKAGE],
+[
+  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
+                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+  define([acl_frompackage_]NAME, [$2])
+  popdef([NAME])
+  pushdef([PACK],[$2])
+  pushdef([PACKUP],[m4_translit(PACK,[abcdefghijklmnopqrstuvwxyz./+-],
+                                     [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+  define([acl_libsinpackage_]PACKUP,
+    m4_ifdef([acl_libsinpackage_]PACKUP, [m4_defn([acl_libsinpackage_]PACKUP)[, ]],)[lib$1])
+  popdef([PACKUP])
+  popdef([PACK])
+])
+
+dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
+dnl the libraries corresponding to explicit and implicit dependencies.
+dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
+dnl Also, sets the LIB${NAME}_PREFIX variable to nonempty if libname was found
+dnl in ${LIB${NAME}_PREFIX}/$acl_libdirstem.
+AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
+[
+  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
+  pushdef([NAME],[m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./+-],
+                                   [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+  pushdef([PACK],[m4_ifdef([acl_frompackage_]NAME, [acl_frompackage_]NAME, lib[$1])])
+  pushdef([PACKUP],[m4_translit(PACK,[abcdefghijklmnopqrstuvwxyz./+-],
+                                     [ABCDEFGHIJKLMNOPQRSTUVWXYZ____])])
+  pushdef([PACKLIBS],[m4_ifdef([acl_frompackage_]NAME, [acl_libsinpackage_]PACKUP, lib[$1])])
+  dnl Autoconf >= 2.61 supports dots in --with options.
+  pushdef([P_A_C_K],[m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.61]),[-1],[m4_translit(PACK,[.],[_])],PACK)])
+  dnl By default, look in $includedir and $libdir.
+  use_additional=yes
+  AC_LIB_WITH_FINAL_PREFIX([
+    eval additional_includedir=\"$includedir\"
+    eval additional_libdir=\"$libdir\"
+  ])
+  AC_ARG_WITH(P_A_C_K[-prefix],
+[[  --with-]]P_A_C_K[[-prefix[=DIR]  search for ]PACKLIBS[ in DIR/include and DIR/lib
+  --without-]]P_A_C_K[[-prefix     don't search for ]PACKLIBS[ in includedir and libdir]],
+[
+    if test "X$withval" = "Xno"; then
+      use_additional=no
+    else
+      if test "X$withval" = "X"; then
+        AC_LIB_WITH_FINAL_PREFIX([
+          eval additional_includedir=\"$includedir\"
+          eval additional_libdir=\"$libdir\"
+        ])
+      else
+        additional_includedir="$withval/include"
+        additional_libdir="$withval/$acl_libdirstem"
+        if test "$acl_libdirstem2" != "$acl_libdirstem" \
+           && ! test -d "$withval/$acl_libdirstem"; then
+          additional_libdir="$withval/$acl_libdirstem2"
+        fi
+      fi
+    fi
+])
+  dnl Search the library and its dependencies in $additional_libdir and
+  dnl $LDFLAGS. Using breadth-first-search.
+  LIB[]NAME=
+  LTLIB[]NAME=
+  INC[]NAME=
+  LIB[]NAME[]_PREFIX=
+  dnl HAVE_LIB${NAME} is an indicator that LIB${NAME}, LTLIB${NAME} have been
+  dnl computed. So it has to be reset here.
+  HAVE_LIB[]NAME=
+  rpathdirs=
+  ltrpathdirs=
+  names_already_handled=
+  names_next_round='$1 $2'
+  while test -n "$names_next_round"; do
+    names_this_round="$names_next_round"
+    names_next_round=
+    for name in $names_this_round; do
+      already_handled=
+      for n in $names_already_handled; do
+        if test "$n" = "$name"; then
+          already_handled=yes
+          break
+        fi
+      done
+      if test -z "$already_handled"; then
+        names_already_handled="$names_already_handled $name"
+        dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
+        dnl or AC_LIB_HAVE_LINKFLAGS call.
+        uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./+-|ABCDEFGHIJKLMNOPQRSTUVWXYZ____|'`
+        eval value=\"\$HAVE_LIB$uppername\"
+        if test -n "$value"; then
+          if test "$value" = yes; then
+            eval value=\"\$LIB$uppername\"
+            test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
+            eval value=\"\$LTLIB$uppername\"
+            test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
+          else
+            dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
+            dnl that this library doesn't exist. So just drop it.
+            :
+          fi
+        else
+          dnl Search the library lib$name in $additional_libdir and $LDFLAGS
+          dnl and the already constructed $LIBNAME/$LTLIBNAME.
+          found_dir=
+          found_la=
+          found_so=
+          found_a=
+          eval libname=\"$acl_libname_spec\"    # typically: libname=lib$name
+          if test -n "$acl_shlibext"; then
+            shrext=".$acl_shlibext"             # typically: shrext=.so
+          else
+            shrext=
+          fi
+          if test $use_additional = yes; then
+            dir="$additional_libdir"
+            dnl The same code as in the loop below:
+            dnl First look for a shared library.
+            if test -n "$acl_shlibext"; then
+              if test -f "$dir/$libname$shrext"; then
+                found_dir="$dir"
+                found_so="$dir/$libname$shrext"
+              else
+                if test "$acl_library_names_spec" = '$libname$shrext$versuffix'; then
+                  ver=`(cd "$dir" && \
+                        for f in "$libname$shrext".*; do echo "$f"; done \
+                        | sed -e "s,^$libname$shrext\\\\.,," \
+                        | sort -t '.' -n -r -k1,1 -k2,2 -k3,3 -k4,4 -k5,5 \
+                        | sed 1q ) 2>/dev/null`
+                  if test -n "$ver" && test -f "$dir/$libname$shrext.$ver"; then
+                    found_dir="$dir"
+                    found_so="$dir/$libname$shrext.$ver"
+                  fi
+                else
+                  eval library_names=\"$acl_library_names_spec\"
+                  for f in $library_names; do
+                    if test -f "$dir/$f"; then
+                      found_dir="$dir"
+                      found_so="$dir/$f"
+                      break
+                    fi
+                  done
+                fi
+              fi
+            fi
+            dnl Then look for a static library.
+            if test "X$found_dir" = "X"; then
+              if test -f "$dir/$libname.$acl_libext"; then
+                found_dir="$dir"
+                found_a="$dir/$libname.$acl_libext"
+              fi
+            fi
+            if test "X$found_dir" != "X"; then
+              if test -f "$dir/$libname.la"; then
+                found_la="$dir/$libname.la"
+              fi
+            fi
+          fi
+          if test "X$found_dir" = "X"; then
+            for x in $LDFLAGS $LTLIB[]NAME; do
+              AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+              case "$x" in
+                -L*)
+                  dir=`echo "X$x" | sed -e 's/^X-L//'`
+                  dnl First look for a shared library.
+                  if test -n "$acl_shlibext"; then
+                    if test -f "$dir/$libname$shrext"; then
+                      found_dir="$dir"
+                      found_so="$dir/$libname$shrext"
+                    else
+                      if test "$acl_library_names_spec" = '$libname$shrext$versuffix'; then
+                        ver=`(cd "$dir" && \
+                              for f in "$libname$shrext".*; do echo "$f"; done \
+                              | sed -e "s,^$libname$shrext\\\\.,," \
+                              | sort -t '.' -n -r -k1,1 -k2,2 -k3,3 -k4,4 -k5,5 \
+                              | sed 1q ) 2>/dev/null`
+                        if test -n "$ver" && test -f "$dir/$libname$shrext.$ver"; then
+                          found_dir="$dir"
+                          found_so="$dir/$libname$shrext.$ver"
+                        fi
+                      else
+                        eval library_names=\"$acl_library_names_spec\"
+                        for f in $library_names; do
+                          if test -f "$dir/$f"; then
+                            found_dir="$dir"
+                            found_so="$dir/$f"
+                            break
+                          fi
+                        done
+                      fi
+                    fi
+                  fi
+                  dnl Then look for a static library.
+                  if test "X$found_dir" = "X"; then
+                    if test -f "$dir/$libname.$acl_libext"; then
+                      found_dir="$dir"
+                      found_a="$dir/$libname.$acl_libext"
+                    fi
+                  fi
+                  if test "X$found_dir" != "X"; then
+                    if test -f "$dir/$libname.la"; then
+                      found_la="$dir/$libname.la"
+                    fi
+                  fi
+                  ;;
+              esac
+              if test "X$found_dir" != "X"; then
+                break
+              fi
+            done
+          fi
+          if test "X$found_dir" != "X"; then
+            dnl Found the library.
+            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
+            if test "X$found_so" != "X"; then
+              dnl Linking with a shared library. We attempt to hardcode its
+              dnl directory into the executable's runpath, unless it's the
+              dnl standard /usr/lib.
+              if test "$enable_rpath" = no \
+                 || test "X$found_dir" = "X/usr/$acl_libdirstem" \
+                 || test "X$found_dir" = "X/usr/$acl_libdirstem2"; then
+                dnl No hardcoding is needed.
+                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+              else
+                dnl Use an explicit option to hardcode DIR into the resulting
+                dnl binary.
+                dnl Potentially add DIR to ltrpathdirs.
+                dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
+                haveit=
+                for x in $ltrpathdirs; do
+                  if test "X$x" = "X$found_dir"; then
+                    haveit=yes
+                    break
+                  fi
+                done
+                if test -z "$haveit"; then
+                  ltrpathdirs="$ltrpathdirs $found_dir"
+                fi
+                dnl The hardcoding into $LIBNAME is system dependent.
+                if test "$acl_hardcode_direct" = yes; then
+                  dnl Using DIR/libNAME.so during linking hardcodes DIR into the
+                  dnl resulting binary.
+                  LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+                else
+                  if test -n "$acl_hardcode_libdir_flag_spec" && test "$acl_hardcode_minus_L" = no; then
+                    dnl Use an explicit option to hardcode DIR into the resulting
+                    dnl binary.
+                    LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+                    dnl Potentially add DIR to rpathdirs.
+                    dnl The rpathdirs will be appended to $LIBNAME at the end.
+                    haveit=
+                    for x in $rpathdirs; do
+                      if test "X$x" = "X$found_dir"; then
+                        haveit=yes
+                        break
+                      fi
+                    done
+                    if test -z "$haveit"; then
+                      rpathdirs="$rpathdirs $found_dir"
+                    fi
+                  else
+                    dnl Rely on "-L$found_dir".
+                    dnl But don't add it if it's already contained in the LDFLAGS
+                    dnl or the already constructed $LIBNAME
+                    haveit=
+                    for x in $LDFLAGS $LIB[]NAME; do
+                      AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+                      if test "X$x" = "X-L$found_dir"; then
+                        haveit=yes
+                        break
+                      fi
+                    done
+                    if test -z "$haveit"; then
+                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
+                    fi
+                    if test "$acl_hardcode_minus_L" != no; then
+                      dnl FIXME: Not sure whether we should use
+                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
+                      dnl here.
+                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+                    else
+                      dnl We cannot use $acl_hardcode_runpath_var and LD_RUN_PATH
+                      dnl here, because this doesn't fit in flags passed to the
+                      dnl compiler. So give up. No hardcoding. This affects only
+                      dnl very old systems.
+                      dnl FIXME: Not sure whether we should use
+                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
+                      dnl here.
+                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
+                    fi
+                  fi
+                fi
+              fi
+            else
+              if test "X$found_a" != "X"; then
+                dnl Linking with a static library.
+                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
+              else
+                dnl We shouldn't come here, but anyway it's good to have a
+                dnl fallback.
+                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
+              fi
+            fi
+            dnl Assume the include files are nearby.
+            additional_includedir=
+            case "$found_dir" in
+              */$acl_libdirstem | */$acl_libdirstem/)
+                basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem/"'*$,,'`
+                if test "$name" = '$1'; then
+                  LIB[]NAME[]_PREFIX="$basedir"
+                fi
+                additional_includedir="$basedir/include"
+                ;;
+              */$acl_libdirstem2 | */$acl_libdirstem2/)
+                basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem2/"'*$,,'`
+                if test "$name" = '$1'; then
+                  LIB[]NAME[]_PREFIX="$basedir"
+                fi
+                additional_includedir="$basedir/include"
+                ;;
+            esac
+            if test "X$additional_includedir" != "X"; then
+              dnl Potentially add $additional_includedir to $INCNAME.
+              dnl But don't add it
+              dnl   1. if it's the standard /usr/include,
+              dnl   2. if it's /usr/local/include and we are using GCC on Linux,
+              dnl   3. if it's already present in $CPPFLAGS or the already
+              dnl      constructed $INCNAME,
+              dnl   4. if it doesn't exist as a directory.
+              if test "X$additional_includedir" != "X/usr/include"; then
+                haveit=
+                if test "X$additional_includedir" = "X/usr/local/include"; then
+                  if test -n "$GCC"; then
+                    case $host_os in
+                      linux* | gnu* | k*bsd*-gnu) haveit=yes;;
+                    esac
+                  fi
+                fi
+                if test -z "$haveit"; then
+                  for x in $CPPFLAGS $INC[]NAME; do
+                    AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+                    if test "X$x" = "X-I$additional_includedir"; then
+                      haveit=yes
+                      break
+                    fi
+                  done
+                  if test -z "$haveit"; then
+                    if test -d "$additional_includedir"; then
+                      dnl Really add $additional_includedir to $INCNAME.
+                      INC[]NAME="${INC[]NAME}${INC[]NAME:+ }-I$additional_includedir"
+                    fi
+                  fi
+                fi
+              fi
+            fi
+            dnl Look for dependencies.
+            if test -n "$found_la"; then
+              dnl Read the .la file. It defines the variables
+              dnl dlname, library_names, old_library, dependency_libs, current,
+              dnl age, revision, installed, dlopen, dlpreopen, libdir.
+              save_libdir="$libdir"
+              case "$found_la" in
+                */* | *\\*) . "$found_la" ;;
+                *) . "./$found_la" ;;
+              esac
+              libdir="$save_libdir"
+              dnl We use only dependency_libs.
+              for dep in $dependency_libs; do
+                case "$dep" in
+                  -L*)
+                    additional_libdir=`echo "X$dep" | sed -e 's/^X-L//'`
+                    dnl Potentially add $additional_libdir to $LIBNAME and $LTLIBNAME.
+                    dnl But don't add it
+                    dnl   1. if it's the standard /usr/lib,
+                    dnl   2. if it's /usr/local/lib and we are using GCC on Linux,
+                    dnl   3. if it's already present in $LDFLAGS or the already
+                    dnl      constructed $LIBNAME,
+                    dnl   4. if it doesn't exist as a directory.
+                    if test "X$additional_libdir" != "X/usr/$acl_libdirstem" \
+                       && test "X$additional_libdir" != "X/usr/$acl_libdirstem2"; then
+                      haveit=
+                      if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem" \
+                         || test "X$additional_libdir" = "X/usr/local/$acl_libdirstem2"; then
+                        if test -n "$GCC"; then
+                          case $host_os in
+                            linux* | gnu* | k*bsd*-gnu) haveit=yes;;
+                          esac
+                        fi
+                      fi
+                      if test -z "$haveit"; then
+                        haveit=
+                        for x in $LDFLAGS $LIB[]NAME; do
+                          AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+                          if test "X$x" = "X-L$additional_libdir"; then
+                            haveit=yes
+                            break
+                          fi
+                        done
+                        if test -z "$haveit"; then
+                          if test -d "$additional_libdir"; then
+                            dnl Really add $additional_libdir to $LIBNAME.
+                            LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$additional_libdir"
+                          fi
+                        fi
+                        haveit=
+                        for x in $LDFLAGS $LTLIB[]NAME; do
+                          AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+                          if test "X$x" = "X-L$additional_libdir"; then
+                            haveit=yes
+                            break
+                          fi
+                        done
+                        if test -z "$haveit"; then
+                          if test -d "$additional_libdir"; then
+                            dnl Really add $additional_libdir to $LTLIBNAME.
+                            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$additional_libdir"
+                          fi
+                        fi
+                      fi
+                    fi
+                    ;;
+                  -R*)
+                    dir=`echo "X$dep" | sed -e 's/^X-R//'`
+                    if test "$enable_rpath" != no; then
+                      dnl Potentially add DIR to rpathdirs.
+                      dnl The rpathdirs will be appended to $LIBNAME at the end.
+                      haveit=
+                      for x in $rpathdirs; do
+                        if test "X$x" = "X$dir"; then
+                          haveit=yes
+                          break
+                        fi
+                      done
+                      if test -z "$haveit"; then
+                        rpathdirs="$rpathdirs $dir"
+                      fi
+                      dnl Potentially add DIR to ltrpathdirs.
+                      dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
+                      haveit=
+                      for x in $ltrpathdirs; do
+                        if test "X$x" = "X$dir"; then
+                          haveit=yes
+                          break
+                        fi
+                      done
+                      if test -z "$haveit"; then
+                        ltrpathdirs="$ltrpathdirs $dir"
+                      fi
+                    fi
+                    ;;
+                  -l*)
+                    dnl Handle this in the next round.
+                    names_next_round="$names_next_round "`echo "X$dep" | sed -e 's/^X-l//'`
+                    ;;
+                  *.la)
+                    dnl Handle this in the next round. Throw away the .la's
+                    dnl directory; it is already contained in a preceding -L
+                    dnl option.
+                    names_next_round="$names_next_round "`echo "X$dep" | sed -e 's,^X.*/,,' -e 's,^lib,,' -e 's,\.la$,,'`
+                    ;;
+                  *)
+                    dnl Most likely an immediate library name.
+                    LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$dep"
+                    LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$dep"
+                    ;;
+                esac
+              done
+            fi
+          else
+            dnl Didn't find the library; assume it is in the system directories
+            dnl known to the linker and runtime loader. (All the system
+            dnl directories known to the linker should also be known to the
+            dnl runtime loader, otherwise the system is severely misconfigured.)
+            LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
+            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-l$name"
+          fi
+        fi
+      fi
+    done
+  done
+  if test "X$rpathdirs" != "X"; then
+    if test -n "$acl_hardcode_libdir_separator"; then
+      dnl Weird platform: only the last -rpath option counts, the user must
+      dnl pass all path elements in one option. We can arrange that for a
+      dnl single library, but not when more than one $LIBNAMEs are used.
+      alldirs=
+      for found_dir in $rpathdirs; do
+        alldirs="${alldirs}${alldirs:+$acl_hardcode_libdir_separator}$found_dir"
+      done
+      dnl Note: acl_hardcode_libdir_flag_spec uses $libdir and $wl.
+      acl_save_libdir="$libdir"
+      libdir="$alldirs"
+      eval flag=\"$acl_hardcode_libdir_flag_spec\"
+      libdir="$acl_save_libdir"
+      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
+    else
+      dnl The -rpath options are cumulative.
+      for found_dir in $rpathdirs; do
+        acl_save_libdir="$libdir"
+        libdir="$found_dir"
+        eval flag=\"$acl_hardcode_libdir_flag_spec\"
+        libdir="$acl_save_libdir"
+        LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
+      done
+    fi
+  fi
+  if test "X$ltrpathdirs" != "X"; then
+    dnl When using libtool, the option that works for both libraries and
+    dnl executables is -R. The -R options are cumulative.
+    for found_dir in $ltrpathdirs; do
+      LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-R$found_dir"
+    done
+  fi
+  popdef([P_A_C_K])
+  popdef([PACKLIBS])
+  popdef([PACKUP])
+  popdef([PACK])
+  popdef([NAME])
+])
+
+dnl AC_LIB_APPENDTOVAR(VAR, CONTENTS) appends the elements of CONTENTS to VAR,
+dnl unless already present in VAR.
+dnl Works only for CPPFLAGS, not for LIB* variables because that sometimes
+dnl contains two or three consecutive elements that belong together.
+AC_DEFUN([AC_LIB_APPENDTOVAR],
+[
+  for element in [$2]; do
+    haveit=
+    for x in $[$1]; do
+      AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+      if test "X$x" = "X$element"; then
+        haveit=yes
+        break
+      fi
+    done
+    if test -z "$haveit"; then
+      [$1]="${[$1]}${[$1]:+ }$element"
+    fi
+  done
+])
+
+dnl For those cases where a variable contains several -L and -l options
+dnl referring to unknown libraries and directories, this macro determines the
+dnl necessary additional linker options for the runtime path.
+dnl AC_LIB_LINKFLAGS_FROM_LIBS([LDADDVAR], [LIBSVALUE], [USE-LIBTOOL])
+dnl sets LDADDVAR to linker options needed together with LIBSVALUE.
+dnl If USE-LIBTOOL evaluates to non-empty, linking with libtool is assumed,
+dnl otherwise linking without libtool is assumed.
+AC_DEFUN([AC_LIB_LINKFLAGS_FROM_LIBS],
+[
+  AC_REQUIRE([AC_LIB_RPATH])
+  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
+  $1=
+  if test "$enable_rpath" != no; then
+    if test -n "$acl_hardcode_libdir_flag_spec" && test "$acl_hardcode_minus_L" = no; then
+      dnl Use an explicit option to hardcode directories into the resulting
+      dnl binary.
+      rpathdirs=
+      next=
+      for opt in $2; do
+        if test -n "$next"; then
+          dir="$next"
+          dnl No need to hardcode the standard /usr/lib.
+          if test "X$dir" != "X/usr/$acl_libdirstem" \
+             && test "X$dir" != "X/usr/$acl_libdirstem2"; then
+            rpathdirs="$rpathdirs $dir"
+          fi
+          next=
+        else
+          case $opt in
+            -L) next=yes ;;
+            -L*) dir=`echo "X$opt" | sed -e 's,^X-L,,'`
+                 dnl No need to hardcode the standard /usr/lib.
+                 if test "X$dir" != "X/usr/$acl_libdirstem" \
+                    && test "X$dir" != "X/usr/$acl_libdirstem2"; then
+                   rpathdirs="$rpathdirs $dir"
+                 fi
+                 next= ;;
+            *) next= ;;
+          esac
+        fi
+      done
+      if test "X$rpathdirs" != "X"; then
+        if test -n ""$3""; then
+          dnl libtool is used for linking. Use -R options.
+          for dir in $rpathdirs; do
+            $1="${$1}${$1:+ }-R$dir"
+          done
+        else
+          dnl The linker is used for linking directly.
+          if test -n "$acl_hardcode_libdir_separator"; then
+            dnl Weird platform: only the last -rpath option counts, the user
+            dnl must pass all path elements in one option.
+            alldirs=
+            for dir in $rpathdirs; do
+              alldirs="${alldirs}${alldirs:+$acl_hardcode_libdir_separator}$dir"
+            done
+            acl_save_libdir="$libdir"
+            libdir="$alldirs"
+            eval flag=\"$acl_hardcode_libdir_flag_spec\"
+            libdir="$acl_save_libdir"
+            $1="$flag"
+          else
+            dnl The -rpath options are cumulative.
+            for dir in $rpathdirs; do
+              acl_save_libdir="$libdir"
+              libdir="$dir"
+              eval flag=\"$acl_hardcode_libdir_flag_spec\"
+              libdir="$acl_save_libdir"
+              $1="${$1}${$1:+ }$flag"
+            done
+          fi
+        fi
+      fi
+    fi
+  fi
+  AC_SUBST([$1])
+])
diff --git a/m4/lib-prefix.m4 b/m4/lib-prefix.m4
new file mode 100644
index 0000000..ff90f8f
--- /dev/null
+++ b/m4/lib-prefix.m4
@@ -0,0 +1,224 @@
+# lib-prefix.m4 serial 7 (gettext-0.18)
+dnl Copyright (C) 2001-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+dnl AC_LIB_ARG_WITH is synonymous to AC_ARG_WITH in autoconf-2.13, and
+dnl similar to AC_ARG_WITH in autoconf 2.52...2.57 except that is doesn't
+dnl require excessive bracketing.
+ifdef([AC_HELP_STRING],
+[AC_DEFUN([AC_LIB_ARG_WITH], [AC_ARG_WITH([$1],[[$2]],[$3],[$4])])],
+[AC_DEFUN([AC_][LIB_ARG_WITH], [AC_ARG_WITH([$1],[$2],[$3],[$4])])])
+
+dnl AC_LIB_PREFIX adds to the CPPFLAGS and LDFLAGS the flags that are needed
+dnl to access previously installed libraries. The basic assumption is that
+dnl a user will want packages to use other packages he previously installed
+dnl with the same --prefix option.
+dnl This macro is not needed if only AC_LIB_LINKFLAGS is used to locate
+dnl libraries, but is otherwise very convenient.
+AC_DEFUN([AC_LIB_PREFIX],
+[
+  AC_BEFORE([$0], [AC_LIB_LINKFLAGS])
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  dnl By default, look in $includedir and $libdir.
+  use_additional=yes
+  AC_LIB_WITH_FINAL_PREFIX([
+    eval additional_includedir=\"$includedir\"
+    eval additional_libdir=\"$libdir\"
+  ])
+  AC_LIB_ARG_WITH([lib-prefix],
+[  --with-lib-prefix[=DIR] search for libraries in DIR/include and DIR/lib
+  --without-lib-prefix    don't search for libraries in includedir and libdir],
+[
+    if test "X$withval" = "Xno"; then
+      use_additional=no
+    else
+      if test "X$withval" = "X"; then
+        AC_LIB_WITH_FINAL_PREFIX([
+          eval additional_includedir=\"$includedir\"
+          eval additional_libdir=\"$libdir\"
+        ])
+      else
+        additional_includedir="$withval/include"
+        additional_libdir="$withval/$acl_libdirstem"
+      fi
+    fi
+])
+  if test $use_additional = yes; then
+    dnl Potentially add $additional_includedir to $CPPFLAGS.
+    dnl But don't add it
+    dnl   1. if it's the standard /usr/include,
+    dnl   2. if it's already present in $CPPFLAGS,
+    dnl   3. if it's /usr/local/include and we are using GCC on Linux,
+    dnl   4. if it doesn't exist as a directory.
+    if test "X$additional_includedir" != "X/usr/include"; then
+      haveit=
+      for x in $CPPFLAGS; do
+        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+        if test "X$x" = "X-I$additional_includedir"; then
+          haveit=yes
+          break
+        fi
+      done
+      if test -z "$haveit"; then
+        if test "X$additional_includedir" = "X/usr/local/include"; then
+          if test -n "$GCC"; then
+            case $host_os in
+              linux* | gnu* | k*bsd*-gnu) haveit=yes;;
+            esac
+          fi
+        fi
+        if test -z "$haveit"; then
+          if test -d "$additional_includedir"; then
+            dnl Really add $additional_includedir to $CPPFLAGS.
+            CPPFLAGS="${CPPFLAGS}${CPPFLAGS:+ }-I$additional_includedir"
+          fi
+        fi
+      fi
+    fi
+    dnl Potentially add $additional_libdir to $LDFLAGS.
+    dnl But don't add it
+    dnl   1. if it's the standard /usr/lib,
+    dnl   2. if it's already present in $LDFLAGS,
+    dnl   3. if it's /usr/local/lib and we are using GCC on Linux,
+    dnl   4. if it doesn't exist as a directory.
+    if test "X$additional_libdir" != "X/usr/$acl_libdirstem"; then
+      haveit=
+      for x in $LDFLAGS; do
+        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+        if test "X$x" = "X-L$additional_libdir"; then
+          haveit=yes
+          break
+        fi
+      done
+      if test -z "$haveit"; then
+        if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem"; then
+          if test -n "$GCC"; then
+            case $host_os in
+              linux*) haveit=yes;;
+            esac
+          fi
+        fi
+        if test -z "$haveit"; then
+          if test -d "$additional_libdir"; then
+            dnl Really add $additional_libdir to $LDFLAGS.
+            LDFLAGS="${LDFLAGS}${LDFLAGS:+ }-L$additional_libdir"
+          fi
+        fi
+      fi
+    fi
+  fi
+])
+
+dnl AC_LIB_PREPARE_PREFIX creates variables acl_final_prefix,
+dnl acl_final_exec_prefix, containing the values to which $prefix and
+dnl $exec_prefix will expand at the end of the configure script.
+AC_DEFUN([AC_LIB_PREPARE_PREFIX],
+[
+  dnl Unfortunately, prefix and exec_prefix get only finally determined
+  dnl at the end of configure.
+  if test "X$prefix" = "XNONE"; then
+    acl_final_prefix="$ac_default_prefix"
+  else
+    acl_final_prefix="$prefix"
+  fi
+  if test "X$exec_prefix" = "XNONE"; then
+    acl_final_exec_prefix='${prefix}'
+  else
+    acl_final_exec_prefix="$exec_prefix"
+  fi
+  acl_save_prefix="$prefix"
+  prefix="$acl_final_prefix"
+  eval acl_final_exec_prefix=\"$acl_final_exec_prefix\"
+  prefix="$acl_save_prefix"
+])
+
+dnl AC_LIB_WITH_FINAL_PREFIX([statement]) evaluates statement, with the
+dnl variables prefix and exec_prefix bound to the values they will have
+dnl at the end of the configure script.
+AC_DEFUN([AC_LIB_WITH_FINAL_PREFIX],
+[
+  acl_save_prefix="$prefix"
+  prefix="$acl_final_prefix"
+  acl_save_exec_prefix="$exec_prefix"
+  exec_prefix="$acl_final_exec_prefix"
+  $1
+  exec_prefix="$acl_save_exec_prefix"
+  prefix="$acl_save_prefix"
+])
+
+dnl AC_LIB_PREPARE_MULTILIB creates
+dnl - a variable acl_libdirstem, containing the basename of the libdir, either
+dnl   "lib" or "lib64" or "lib/64",
+dnl - a variable acl_libdirstem2, as a secondary possible value for
+dnl   acl_libdirstem, either the same as acl_libdirstem or "lib/sparcv9" or
+dnl   "lib/amd64".
+AC_DEFUN([AC_LIB_PREPARE_MULTILIB],
+[
+  dnl There is no formal standard regarding lib and lib64.
+  dnl On glibc systems, the current practice is that on a system supporting
+  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
+  dnl $prefix/lib64 and 32-bit libraries go under $prefix/lib. We determine
+  dnl the compiler's default mode by looking at the compiler's library search
+  dnl path. If at least one of its elements ends in /lib64 or points to a
+  dnl directory whose absolute pathname ends in /lib64, we assume a 64-bit ABI.
+  dnl Otherwise we use the default, namely "lib".
+  dnl On Solaris systems, the current practice is that on a system supporting
+  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
+  dnl $prefix/lib/64 (which is a symlink to either $prefix/lib/sparcv9 or
+  dnl $prefix/lib/amd64) and 32-bit libraries go under $prefix/lib.
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  acl_libdirstem=lib
+  acl_libdirstem2=
+  case "$host_os" in
+    solaris*)
+      dnl See Solaris 10 Software Developer Collection > Solaris 64-bit Developer's Guide > The Development Environment
+      dnl <http://docs.sun.com/app/docs/doc/816-5138/dev-env?l=en&a=view>.
+      dnl "Portable Makefiles should refer to any library directories using the 64 symbolic link."
+      dnl But we want to recognize the sparcv9 or amd64 subdirectory also if the
+      dnl symlink is missing, so we set acl_libdirstem2 too.
+      AC_CACHE_CHECK([for 64-bit host], [gl_cv_solaris_64bit],
+        [AC_EGREP_CPP([sixtyfour bits], [
+#ifdef _LP64
+sixtyfour bits
+#endif
+           ], [gl_cv_solaris_64bit=yes], [gl_cv_solaris_64bit=no])
+        ])
+      if test $gl_cv_solaris_64bit = yes; then
+        acl_libdirstem=lib/64
+        case "$host_cpu" in
+          sparc*)        acl_libdirstem2=lib/sparcv9 ;;
+          i*86 | x86_64) acl_libdirstem2=lib/amd64 ;;
+        esac
+      fi
+      ;;
+    *)
+      searchpath=`(LC_ALL=C $CC -print-search-dirs) 2>/dev/null | sed -n -e 's,^libraries: ,,p' | sed -e 's,^=,,'`
+      if test -n "$searchpath"; then
+        acl_save_IFS="${IFS= 	}"; IFS=":"
+        for searchdir in $searchpath; do
+          if test -d "$searchdir"; then
+            case "$searchdir" in
+              */lib64/ | */lib64 ) acl_libdirstem=lib64 ;;
+              */../ | */.. )
+                # Better ignore directories of this form. They are misleading.
+                ;;
+              *) searchdir=`cd "$searchdir" && pwd`
+                 case "$searchdir" in
+                   */lib64 ) acl_libdirstem=lib64 ;;
+                 esac ;;
+            esac
+          fi
+        done
+        IFS="$acl_save_IFS"
+      fi
+      ;;
+  esac
+  test -n "$acl_libdirstem2" || acl_libdirstem2="$acl_libdirstem"
+])
diff --git a/m4/localcharset.m4 b/m4/localcharset.m4
new file mode 100644
index 0000000..677aea5
--- /dev/null
+++ b/m4/localcharset.m4
@@ -0,0 +1,17 @@
+# localcharset.m4 serial 7
+dnl Copyright (C) 2002-2020 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_LOCALCHARSET],
+[
+  dnl Prerequisites of lib/localcharset.c.
+  AC_REQUIRE([AM_LANGINFO_CODESET])
+  AC_REQUIRE([gl_FCNTL_O_FLAGS])
+  AC_CHECK_DECLS_ONCE([getc_unlocked])
+
+  dnl Prerequisites of the lib/Makefile.am snippet.
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  AC_REQUIRE([gl_GLIBC21])
+])