Modernize to current gettext, gnulib

* .gitignore, po/.gitignore: Revamp to match current source.
* README: Fix typo in file name.
* am/rmt.m4 (PU_RMT):
Modernize to use AC_PREPROC_IFELSE instead of AC_TRY_CPP.
* am/rmt.m4 (PU_RMT):
* configure.ac:
Modernize to use AS_HELP_STRING instead of AC_HELP_STRING.
* am/system.m4 (PU_SYSTEM):
* configure.ac:
Remove obsolescent AC_HEADER_STDC.  Use AC_CHECK_MEMBERS([struct
stat.st_blksize]) instead of AC_STRUCT_ST_BLKSIZE.
* am/system.m4 (PU_SYSTEM):
Use AC_CHECK_HEADERS_ONCE([sys/time.h]) instead of obsolescent
AC_HEADER_TIME.
* bootstrap: Sync from Gnulib.
* build-aux/bootstrap: Remove.
* bootstrap.conf: Simplify.  Don’t make m4, $source_base.
(bootstrap_post_import_hook):
New function, replacing a direct write.
* configure.ac: Remove calls to no-longer-needed macros
AC_ISC_POSIX, AM_STDBOOL_H, AC_HEADER_STDC, AC_TYPE_SIGNAL.
Modernize to use AC_COMPILE_ELSE instead of AC_TRY_COMPILE.
Remove MU_DEBUG_MODE, paxutils_GNULIB (not sure what those were from).
Fix quoting in warning
Remove Iconv code, as the iconv module should do this now.
Update Gettext version from 0.12.1 (2003) to 0.21 (2020).
Use AC_CONFIG_FILES.
All uses of corresponding C macros changed.
* gnulib.modules, paxlib.modules: Switch from gettext to gettext-h.
* paxlib.modules: Add iconv.

1 files changed, 821 insertions, 364 deletions

diff --git a/bootstrap b/bootstrap
index b7dc9fd..1f375ee 100755
--- a/bootstrap
+++ b/bootstrap
@@ -1,8 +1,10 @@
 #! /bin/sh
+# Print a version string.
+scriptversion=2022-06-04.00; # UTC
 
 # Bootstrap this package from checked-out sources.
 
-# Copyright (C) 2003-2008 Free Software Foundation, Inc.
+# Copyright (C) 2003-2022 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -15,9 +17,17 @@
 # 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/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-# Written by Paul Eggert.
+# Originally written by Paul Eggert.  The canonical version of this
+# script is maintained as build-aux/bootstrap in gnulib, however, to
+# be useful to your project, you should place a copy of it under
+# version control in the top-level directory of your project.  The
+# intent is that all customization can be done with a bootstrap.conf
+# file also maintained in your version control; gnulib comes with a
+# template build-aux/bootstrap.conf to get you started.
+
+# Please report bugs or propose patches to bug-gnulib@gnu.org.
 
 nl='
 '
@@ -26,36 +36,118 @@ nl='
 LC_ALL=C
 export LC_ALL
 
+# Ensure that CDPATH is not set.  Otherwise, the output from cd
+# would cause trouble in at least one use below.
+(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
+
 local_gl_dir=gl
 
-# Temporary directory names.
-bt='._bootmp'
-bt_regex=`echo "$bt"| sed 's/\./[.]/g'`
-bt2=${bt}2
+# Honor $PERL, but work even if there is none.
+PERL="${PERL-perl}"
+
+me=$0
+
+default_gnulib_url=https://git.savannah.gnu.org/git/gnulib.git
 
 usage() {
-  echo >&2 "\
-Usage: $0 [OPTION]...
+  cat <<EOF
+Usage: $me [OPTION]...
 Bootstrap this package from the checked-out sources.
 
 Options:
- --gnulib-srcdir=DIRNAME  Specify the local directory where gnulib
+ --gnulib-srcdir=DIRNAME  specify the local directory where gnulib
                           sources reside.  Use this if you already
                           have gnulib sources on your machine, and
                           do not want to waste your bandwidth downloading
-                          them again.
- --copy                   Copy files instead of creating symbolic links.
- --force                  Attempt to bootstrap even if the sources seem
-                          not to have been checked out.
- --skip-po                Do not download po files.
-
-If the file $0.conf exists in the same directory as this script, its
+                          them again.  Defaults to \$GNULIB_SRCDIR
+ --bootstrap-sync         if this bootstrap script is not identical to
+                          the version in the local gnulib sources,
+                          update this script, and then restart it with
+                          /bin/sh or the shell \$CONFIG_SHELL
+ --no-bootstrap-sync      do not check whether bootstrap is out of sync
+ --copy                   copy files instead of creating symbolic links
+ --force                  attempt to bootstrap even if the sources seem
+                          not to have been checked out
+ --no-git                 do not use git to update gnulib.  Requires that
+                          --gnulib-srcdir point to a correct gnulib snapshot
+ --skip-po                do not download po files
+EOF
+  bootstrap_print_option_usage_hook
+  cat <<EOF
+If the file $me.conf exists in the same directory as this script, its
 contents are read as shell variables to configure the bootstrap.
 
+For build prerequisites, environment variables like \$AUTOCONF and \$AMTAR
+are honored.
+
+Gnulib sources can be fetched in various ways:
+
+ * If this package is in a git repository with a 'gnulib' submodule
+   configured, then that submodule is initialized and updated and sources
+   are fetched from there.  If \$GNULIB_SRCDIR is set (directly or via
+   --gnulib-srcdir) and is a git repository, then it is used as a reference.
+
+ * Otherwise, if \$GNULIB_SRCDIR is set (directly or via --gnulib-srcdir),
+   then sources are fetched from that local directory.  If it is a git
+   repository and \$GNULIB_REVISION is set, then that revision is checked
+   out.
+
+ * Otherwise, if this package is in a git repository with a 'gnulib'
+   submodule configured, then that submodule is initialized and updated and
+   sources are fetched from there.
+
+ * Otherwise, if the 'gnulib' directory does not exist, Gnulib sources are
+   cloned into that directory using git from \$GNULIB_URL, defaulting to
+   $default_gnulib_url.
+   If \$GNULIB_REVISION is set, then that revision is checked out.
+
+ * Otherwise, the existing Gnulib sources in the 'gnulib' directory are
+   used.  If it is a git repository and \$GNULIB_REVISION is set, then that
+   revision is checked out.
+
+If you maintain a package and want to pin a particular revision of the
+Gnulib sources that has been tested with your package, then there are two
+possible approaches: either configure a 'gnulib' submodule with the
+appropriate revision, or set \$GNULIB_REVISION (and if necessary
+\$GNULIB_URL) in $me.conf.
+
 Running without arguments will suffice in most cases.
-"
+EOF
+}
+
+copyright_year=`echo "$scriptversion" | sed -e 's/[^0-9].*//'`
+copyright="Copyright (C) ${copyright_year} Free Software Foundation, Inc.
+License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law."
+
+# warnf_ FORMAT-STRING ARG1...
+warnf_ ()
+{
+  warnf_format_=$1
+  shift
+  nl='
+'
+  case $* in
+    *$nl*) me_=$(printf "$me"|tr "$nl|" '??')
+       printf "$warnf_format_" "$@" | sed "s|^|$me_: |" ;;
+    *) printf "$me: $warnf_format_" "$@" ;;
+  esac >&2
+}
+
+# warn_ WORD1...
+warn_ ()
+{
+  # If IFS does not start with ' ', set it and emit the warning in a subshell.
+  case $IFS in
+    ' '*) warnf_ '%s\n' "$*";;
+    *)    (IFS=' '; warn_ "$@");;
+  esac
 }
 
+# die WORD1...
+die() { warn_ "$@"; exit 1; }
+
 # Configuration.
 
 # Name of the Makefile.am
@@ -67,32 +159,59 @@ gnulib_modules=
 # Any gnulib files needed that are not in modules.
 gnulib_files=
 
-# The command to download all .po files for a specified domain into
-# a specified directory.  Fill in the first %s is the domain name, and
-# the second with the destination directory.  Use rsync's -L and -r
-# options because the latest/%s directory and the .po files within are
-# all symlinks.
+: ${AUTOPOINT=autopoint}
+: ${AUTORECONF=autoreconf}
+
+# A function to be called for each unrecognized option.  Returns 0 if
+# the option in $1 has been processed by the function.  Returns 1 if
+# the option has not been processed by the function.  Override it via
+# your own definition in bootstrap.conf
+
+bootstrap_option_hook() { return 1; }
+
+# A function to be called in order to print the --help information
+# corresponding to user-defined command-line options.
+
+bootstrap_print_option_usage_hook() { :; }
+
+# A function to be called right after gnulib-tool is run.
+# Override it via your own definition in bootstrap.conf.
+bootstrap_post_import_hook() { :; }
+
+# A function to be called after everything else in this script.
+# Override it via your own definition in bootstrap.conf.
+bootstrap_epilogue() { :; }
+
+# The command to download all .po files for a specified domain into a
+# specified directory.  Fill in the first %s with the destination
+# directory and the second with the domain name.
 po_download_command_format=\
-"rsync -Lrtvz 'translationproject.org::tp/latest/%s/' '%s'"
+"wget --mirror --level=1 -nd -nv -A.po -P '%s' \
+ https://translationproject.org/latest/%s/"
 
+# Prefer a non-empty tarname (4th argument of AC_INIT if given), else
+# fall back to the package name (1st argument with munging).
 extract_package_name='
-  /^AC_INIT(/{
-     /.*,.*,.*, */{
-       s///
-       s/[][]//g
-       s/)$//
+  /^AC_INIT(\[*/{
+     s///
+     /^[^,]*,[^,]*,[^,]*,[ []*\([^][ ,)]\)/{
+       s//\1/
+       s/[],)].*//
        p
        q
      }
-     s/AC_INIT(\[*//
-     s/]*,.*//
+     s/[],)].*//
      s/^GNU //
      y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/
-     s/[^A-Za-z0-9_]/-/g
+     s/[^abcdefghijklmnopqrstuvwxyz0123456789_]/-/g
      p
   }
 '
-package=`sed -n "$extract_package_name" configure.ac` || exit
+package=$(${AUTOCONF:-autoconf} --trace AC_INIT:\$4 configure.ac 2>/dev/null)
+if test -z "$package"; then
+  package=$(sed -n "$extract_package_name" configure.ac) \
+      || die 'cannot find package name in configure.ac'
+fi
 gnulib_name=lib$package
 
 build_aux=build-aux
@@ -100,17 +219,14 @@ source_base=lib
 m4_base=m4
 doc_base=doc
 tests_base=tests
-
-# Extra files from gnulib, which override files from other sources.
 gnulib_extra_files="
-	$build_aux/install-sh
-	$build_aux/missing
-	$build_aux/mdate-sh
-	$build_aux/texinfo.tex
-	$build_aux/depcomp
-	$build_aux/config.guess
-	$build_aux/config.sub
-	doc/INSTALL
+        build-aux/install-sh
+        build-aux/mdate-sh
+        build-aux/texinfo.tex
+        build-aux/depcomp
+        build-aux/config.guess
+        build-aux/config.sub
+        doc/INSTALL
 "
 
 # Additional gnulib-tool options to use.  Use "\newline" to break lines.
@@ -126,7 +242,8 @@ XGETTEXT_OPTIONS='\\\
  --flag=error:3:c-format --flag=error_at_line:5:c-format\\\
 '
 
-# Package bug report address for gettext files
+# Package bug report address and copyright holder for gettext files
+COPYRIGHT_HOLDER='Free Software Foundation, Inc.'
 MSGID_BUGS_ADDRESS=bug-$package@gnu.org
 
 # Files we don't want to import.
@@ -145,6 +262,167 @@ copy=false
 # on which version control system (if any) is used in the source directory.
 vc_ignore=auto
 
+# Set this to true in bootstrap.conf to enable --bootstrap-sync by
+# default.
+bootstrap_sync=false
+
+# Use git to update gnulib sources
+use_git=true
+
+check_exists() {
+  if test "$1" = "--verbose"; then
+    ($2 --version </dev/null) >/dev/null 2>&1
+    if test $? -ge 126; then
+      # If not found, run with diagnostics as one may be
+      # presented with env variables to set to find the right version
+      ($2 --version </dev/null)
+    fi
+  else
+    ($1 --version </dev/null) >/dev/null 2>&1
+  fi
+
+  test $? -lt 126
+}
+
+# find_tool ENVVAR NAMES...
+# -------------------------
+# Search for a required program.  Use the value of ENVVAR, if set,
+# otherwise find the first of the NAMES that can be run.
+# If found, set ENVVAR to the program name, die otherwise.
+#
+# FIXME: code duplication, see also gnu-web-doc-update.
+find_tool ()
+{
+  find_tool_envvar=$1
+  shift
+  find_tool_names=$@
+  eval "find_tool_res=\$$find_tool_envvar"
+  if test x"$find_tool_res" = x; then
+    for i; do
+      if check_exists $i; then
+        find_tool_res=$i
+        break
+      fi
+    done
+  fi
+  if test x"$find_tool_res" = x; then
+    warn_ "one of these is required: $find_tool_names;"
+    die   "alternatively set $find_tool_envvar to a compatible tool"
+  fi
+  eval "$find_tool_envvar=\$find_tool_res"
+  eval "export $find_tool_envvar"
+}
+
+# Strip blank and comment lines to leave significant entries.
+gitignore_entries() {
+  sed '/^#/d; /^$/d' "$@"
+}
+
+# If $STR is not already on a line by itself in $FILE, insert it at the start.
+# Entries are inserted at the start of the ignore list to ensure existing
+# entries starting with ! are not overridden.  Such entries support
+# whitelisting exceptions after a more generic blacklist pattern.
+insert_if_absent() {
+  file=$1
+  str=$2
+  test -f $file || touch $file
+  test -r $file || die "Error: failed to read ignore file: $file"
+  duplicate_entries=$(gitignore_entries $file | sort | uniq -d)
+  if [ "$duplicate_entries" ] ; then
+    die "Error: Duplicate entries in $file: " $duplicate_entries
+  fi
+  linesold=$(gitignore_entries $file | wc -l)
+  linesnew=$( { echo "$str"; cat $file; } | gitignore_entries | sort -u | wc -l)
+  if [ $linesold != $linesnew ] ; then
+    { echo "$str" | cat - $file > $file.bak && mv $file.bak $file; } \
+      || die "insert_if_absent $file $str: failed"
+  fi
+}
+
+# Adjust $PATTERN for $VC_IGNORE_FILE and insert it with
+# insert_if_absent.
+insert_vc_ignore() {
+  vc_ignore_file="$1"
+  pattern="$2"
+  case $vc_ignore_file in
+  *.gitignore)
+    # A .gitignore entry that does not start with '/' applies
+    # recursively to subdirectories, so prepend '/' to every
+    # .gitignore entry.
+    pattern=$(echo "$pattern" | sed s,^,/,);;
+  esac
+  insert_if_absent "$vc_ignore_file" "$pattern"
+}
+
+symlink_to_dir()
+{
+  src=$1/$2
+  dst=${3-$2}
+
+  test -f "$src" && {
+
+    # If the destination directory doesn't exist, create it.
+    # This is required at least for "lib/uniwidth/cjk.h".
+    dst_dir=$(dirname "$dst")
+    if ! test -d "$dst_dir"; then
+      mkdir -p "$dst_dir"
+
+      # If we've just created a directory like lib/uniwidth,
+      # tell version control system(s) it's ignorable.
+      # FIXME: for now, this does only one level
+      parent=$(dirname "$dst_dir")
+      for dot_ig in x $vc_ignore; do
+        test $dot_ig = x && continue
+        ig=$parent/$dot_ig
+        insert_vc_ignore $ig "${dst_dir##*/}"
+      done
+    fi
+
+    if $copy; then
+      {
+        test ! -h "$dst" || {
+          echo "$me: rm -f $dst" &&
+          rm -f "$dst"
+        }
+      } &&
+      test -f "$dst" &&
+      cmp -s "$src" "$dst" || {
+        echo "$me: cp -fp $src $dst" &&
+        cp -fp "$src" "$dst"
+      }
+    else
+      # Leave any existing symlink alone, if it already points to the source,
+      # so that broken build tools that care about symlink times
+      # aren't confused into doing unnecessary builds.  Conversely, if the
+      # existing symlink's timestamp is older than the source, make it afresh,
+      # so that broken tools aren't confused into skipping needed builds.  See
+      # <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00326.html>.
+      test -h "$dst" &&
+      src_ls=$(ls -diL "$src" 2>/dev/null) && set $src_ls && src_i=$1 &&
+      dst_ls=$(ls -diL "$dst" 2>/dev/null) && set $dst_ls && dst_i=$1 &&
+      test "$src_i" = "$dst_i" &&
+      both_ls=$(ls -dt "$src" "$dst") &&
+      test "X$both_ls" = "X$dst$nl$src" || {
+        dot_dots=
+        case $src in
+        /*) ;;
+        *)
+          case /$dst/ in
+          *//* | */../* | */./* | /*/*/*/*/*/)
+             die "invalid symlink calculation: $src -> $dst";;
+          /*/*/*/*/)    dot_dots=../../../;;
+          /*/*/*/)      dot_dots=../../;;
+          /*/*/)        dot_dots=../;;
+          esac;;
+        esac
+
+        echo "$me: ln -fs $dot_dots$src $dst" &&
+        ln -fs "$dot_dots$src" "$dst"
+      }
+    fi
+  }
+}
+
 # Override the default configuration, if necessary.
 # Make sure that bootstrap.conf is sourced from the current directory
 # if we were invoked as "sh bootstrap".
@@ -153,13 +431,18 @@ case "$0" in
   *) test -r "$0.conf" && . ./"$0.conf" ;;
 esac
 
-
 if test "$vc_ignore" = auto; then
   vc_ignore=
   test -d .git && vc_ignore=.gitignore
   test -d CVS && vc_ignore="$vc_ignore .cvsignore"
 fi
 
+if test x"$gnulib_modules$gnulib_files$gnulib_extra_files" = x; then
+  use_gnulib=false
+else
+  use_gnulib=true
+fi
+
 # Translate configuration into internal form.
 
 # Parse options.
@@ -170,47 +453,46 @@ do
   --help)
     usage
     exit;;
+  --version)
+    set -e
+    echo "bootstrap $scriptversion"
+    echo "$copyright"
+    exit 0
+    ;;
   --gnulib-srcdir=*)
-    GNULIB_SRCDIR=`expr "X$option" : 'X--gnulib-srcdir=\(.*\)'`;;
+    GNULIB_SRCDIR=${option#--gnulib-srcdir=};;
   --skip-po)
     SKIP_PO=t;;
   --force)
     checkout_only_file=;;
   --copy)
     copy=true;;
+  --bootstrap-sync)
+    bootstrap_sync=true;;
+  --no-bootstrap-sync)
+    bootstrap_sync=false;;
+  --no-git)
+    use_git=false;;
   *)
-    echo >&2 "$0: $option: unknown option"
-    exit 1;;
+    bootstrap_option_hook $option || die "$option: unknown option";;
   esac
 done
 
+$use_git || test -d "$GNULIB_SRCDIR" \
+  || die "Error: --no-git requires --gnulib-srcdir"
+
 if test -n "$checkout_only_file" && test ! -r "$checkout_only_file"; then
-  echo "$0: Bootstrapping from a non-checked-out distribution is risky." >&2
-  exit 1
+  die "Bootstrapping from a non-checked-out distribution is risky."
 fi
 
-# If $STR is not already on a line by itself in $FILE, insert it,
-# sorting the new contents of the file and replacing $FILE with the result.
-insert_sorted_if_absent() {
-  file=$1
-  str=$2
-  test -f $file || touch $file
-  echo "$str" | sort -u - $file | cmp -s - $file \
-    || echo "$str" | sort -u - $file -o $file \
-    || exit 1
-}
-
 # Die if there is no AC_CONFIG_AUX_DIR($build_aux) line in configure.ac.
 found_aux_dir=no
-grep '^[	 ]*AC_CONFIG_AUX_DIR(\['"$build_aux"'\])' configure.ac \
+grep '^[	 ]*AC_CONFIG_AUX_DIR(\['"$build_aux"'])' configure.ac \
     >/dev/null && found_aux_dir=yes
 grep '^[	 ]*AC_CONFIG_AUX_DIR('"$build_aux"')' configure.ac \
     >/dev/null && found_aux_dir=yes
-if test $found_aux_dir = no; then
-  echo "$0: expected line not found in configure.ac. Add the following:" >&2
-  echo "  AC_CONFIG_AUX_DIR([$build_aux])" >&2
-  exit 1
-fi
+test $found_aux_dir = yes \
+  || die "configure.ac lacks 'AC_CONFIG_AUX_DIR([$build_aux])'; add it"
 
 # If $build_aux doesn't exist, create it now, otherwise some bits
 # below will malfunction.  If creating it, also mark it as ignored.
@@ -218,114 +500,390 @@ if test ! -d $build_aux; then
   mkdir $build_aux
   for dot_ig in x $vc_ignore; do
     test $dot_ig = x && continue
-    insert_sorted_if_absent $dot_ig $build_aux
+    insert_vc_ignore $dot_ig $build_aux
+  done
+fi
+
+# Note this deviates from the version comparison in automake
+# in that it treats 1.5 < 1.5.0, and treats 1.4.4a < 1.4-p3a
+# but this should suffice as we won't be specifying old
+# version formats or redundant trailing .0 in bootstrap.conf.
+# If we did want full compatibility then we should probably
+# use m4_version_compare from autoconf.
+sort_ver() { # sort -V is not generally available
+  ver1="$1"
+  ver2="$2"
+
+  # split on '.' and compare each component
+  i=1
+  while : ; do
+    p1=$(echo "$ver1" | cut -d. -f$i)
+    p2=$(echo "$ver2" | cut -d. -f$i)
+    if [ ! "$p1" ]; then
+      echo "$1 $2"
+      break
+    elif [ ! "$p2" ]; then
+      echo "$2 $1"
+      break
+    elif [ ! "$p1" = "$p2" ]; then
+      if [ "$p1" -gt "$p2" ] 2>/dev/null; then # numeric comparison
+        echo "$2 $1"
+      elif [ "$p2" -gt "$p1" ] 2>/dev/null; then # numeric comparison
+        echo "$1 $2"
+      else # numeric, then lexicographic comparison
+        lp=$(printf "$p1\n$p2\n" | LANG=C sort -n | tail -n1)
+        if [ "$lp" = "$p2" ]; then
+          echo "$1 $2"
+        else
+          echo "$2 $1"
+        fi
+      fi
+      break
+    fi
+    i=$(($i+1))
+  done
+}
+
+get_version_sed='
+# Move version to start of line.
+s/.*[v ]\([0-9]\)/\1/
+
+# Skip lines that do not start with version.
+/^[0-9]/!d
+
+# Remove characters after the version.
+s/[^.a-z0-9-].*//
+
+# The first component must be digits only.
+s/^\([0-9]*\)[a-z-].*/\1/
+
+#the following essentially does s/5.005/5.5/
+s/\.0*\([1-9]\)/.\1/g
+p
+q'
+
+get_version() {
+  app=$1
+
+  $app --version >/dev/null 2>&1 || { $app --version; return 1; }
+
+  $app --version 2>&1 | sed -n "$get_version_sed"
+}
+
+check_versions() {
+  ret=0
+
+  while read app req_ver; do
+    # We only need libtoolize from the libtool package.
+    if test "$app" = libtool; then
+      app=libtoolize
+    fi
+    # Exempt git if --no-git is in effect.
+    if test "$app" = git; then
+      $use_git || continue
+    fi
+    # Honor $APP variables ($TAR, $AUTOCONF, etc.)
+    appvar=$(echo $app | LC_ALL=C tr '[a-z]-' '[A-Z]_')
+    test "$appvar" = TAR && appvar=AMTAR
+    case $appvar in
+        GZIP) ;; # Do not use $GZIP:  it contains gzip options.
+        PERL::*) ;; # Keep perl modules as-is
+        *) eval "app=\${$appvar-$app}" ;;
+    esac
+
+    # Handle the still-experimental Automake-NG programs specially.
+    # They remain named as the mainstream Automake programs ("automake",
+    # and "aclocal") to avoid gratuitous incompatibilities with
+    # pre-existing usages (by, say, autoreconf, or custom autogen.sh
+    # scripts), but correctly identify themselves (as being part of
+    # "GNU automake-ng") when asked their version.
+    case $app in
+      automake-ng|aclocal-ng)
+        app=${app%-ng}
+        ($app --version | grep '(GNU automake-ng)') >/dev/null 2>&1 || {
+          warn_ "Error: '$app' not found or not from Automake-NG"
+          ret=1
+          continue
+        } ;;
+      # Another check is for perl modules.  These can be written as
+      # e.g. perl::XML::XPath in case of XML::XPath module, etc.
+      perl::*)
+        # Extract module name
+        app="${app#perl::}"
+        if ! $PERL -m"$app" -e 'exit 0' >/dev/null 2>&1; then
+          warn_ "Error: perl module '$app' not found"
+          ret=1
+        fi
+        continue
+        ;;
+    esac
+    if [ "$req_ver" = "-" ]; then
+      # Merely require app to exist; not all prereq apps are well-behaved
+      # so we have to rely on $? rather than get_version.
+      if ! check_exists --verbose $app; then
+        warn_ "Error: '$app' not found"
+        ret=1
+      fi
+    else
+      # Require app to produce a new enough version string.
+      inst_ver=$(get_version $app)
+      if [ ! "$inst_ver" ]; then
+        warn_ "Error: '$app' not found"
+        ret=1
+      else
+        latest_ver=$(sort_ver $req_ver $inst_ver | cut -d' ' -f2)
+        if [ ! "$latest_ver" = "$inst_ver" ]; then
+          warnf_ '%s\n'                                        \
+              "Error: '$app' version == $inst_ver is too old"  \
+              "       '$app' version >= $req_ver is required"
+          ret=1
+        fi
+      fi
+    fi
   done
+
+  return $ret
+}
+
+print_versions() {
+  echo "Program    Min_version"
+  echo "----------------------"
+  printf %s "$buildreq"
+  echo "----------------------"
+  # can't depend on column -t
+}
+
+# Find sha1sum, named gsha1sum on MacPorts, shasum on Mac OS X 10.6.
+# Also find the compatible sha1 utility on the BSDs
+if test x"$SKIP_PO" = x; then
+  find_tool SHA1SUM sha1sum gsha1sum shasum sha1
+fi
+
+use_libtool=0
+# We'd like to use grep -E, to see if any of LT_INIT,
+# AC_PROG_LIBTOOL, AM_PROG_LIBTOOL is used in configure.ac,
+# but that's not portable enough (e.g., for Solaris).
+grep '^[	 ]*A[CM]_PROG_LIBTOOL' configure.ac >/dev/null \
+  && use_libtool=1
+grep '^[	 ]*LT_INIT' configure.ac >/dev/null \
+  && use_libtool=1
+if test $use_libtool = 1; then
+  find_tool LIBTOOLIZE glibtoolize libtoolize
+fi
+
+# gnulib-tool requires at least automake and autoconf.
+# If either is not listed, add it (with minimum version) as a prerequisite.
+case $buildreq in
+  *automake*) ;;
+  *) buildreq="automake 1.9
+$buildreq" ;;
+esac
+case $buildreq in
+  *autoconf*) ;;
+  *) buildreq="autoconf 2.59
+$buildreq" ;;
+esac
+
+# When we can deduce that gnulib-tool will require patch,
+# and when patch is not already listed as a prerequisite, add it, too.
+if test -d "$local_gl_dir" \
+    && ! find "$local_gl_dir" -name '*.diff' -exec false {} +; then
+  case $buildreq in
+    *patch*) ;;
+    *) buildreq="patch -
+$buildreq" ;;
+  esac
+fi
+
+if ! printf "$buildreq" | check_versions; then
+  echo >&2
+  if test -f README-prereq; then
+    die "See README-prereq for how to get the prerequisite programs"
+  else
+    die "Please install the prerequisite programs"
+  fi
+fi
+
+# Warn the user if autom4te appears to be broken; this causes known
+# issues with at least gettext 0.18.3.
+probe=$(echo 'm4_quote([hi])' | autom4te -l M4sugar -t 'm4_quote:$%' -)
+if test "x$probe" != xhi; then
+  warn_ "WARNING: your autom4te wrapper eats stdin;"
+  warn_ "if bootstrap fails, consider upgrading your autotools"
 fi
 
 echo "$0: Bootstrapping from checked-out $package sources..."
 
 # See if we can use gnulib's git-merge-changelog merge driver.
-if test -d .git && (git --version) >/dev/null 2>/dev/null ; then
+if $use_git && test -d .git && check_exists git; then
   if git config merge.merge-changelog.driver >/dev/null ; then
     :
-  elif (git-merge-changelog --version) >/dev/null 2>/dev/null ; then
-    echo "initializing git-merge-changelog driver"
+  elif check_exists git-merge-changelog; then
+    echo "$0: initializing git-merge-changelog driver"
     git config merge.merge-changelog.name 'GNU-style ChangeLog merge driver'
     git config merge.merge-changelog.driver 'git-merge-changelog %O %A %B'
   else
-    echo "consider installing git-merge-changelog from gnulib"
+    echo "$0: consider installing git-merge-changelog from gnulib"
   fi
 fi
 
 
 cleanup_gnulib() {
   status=$?
-  rm -fr gnulib
+  rm -fr "$gnulib_path"
   exit $status
 }
 
 git_modules_config () {
-  GIT_CONFIG_LOCAL=.gitmodules git config "$@"
+  test -f .gitmodules && git config --file .gitmodules "$@"
 }
 
-# Get gnulib files.
+if $use_gnulib; then
+  if $use_git; then
+    gnulib_path=$(git_modules_config submodule.gnulib.path)
+    test -z "$gnulib_path" && gnulib_path=gnulib
+  fi
+
+  # Get gnulib files.  Populate $GNULIB_SRCDIR, possibly updating a
+  # submodule, for use in the rest of the script.
 
-case ${GNULIB_SRCDIR--} in
--)
-  if git_modules_config submodule.gnulib.url >/dev/null; then
-    echo "$0: getting gnulib files..."
-    git submodule init || exit $?
-    git submodule update || exit $?
+  case ${GNULIB_SRCDIR--} in
+  -)
+    # Note that $use_git is necessarily true in this case.
+    if git_modules_config submodule.gnulib.url >/dev/null; then
+      echo "$0: getting gnulib files..."
+      git submodule init -- "$gnulib_path" || exit $?
+      git submodule update -- "$gnulib_path" || exit $?
 
-  elif [ ! -d gnulib ]; then
-    echo "$0: getting gnulib files..."
+    elif [ ! -d "$gnulib_path" ]; then
+      echo "$0: getting gnulib files..."
 
-    trap cleanup_gnulib 1 2 13 15
+      trap cleanup_gnulib 1 2 13 15
 
-    git clone --help|grep depth > /dev/null && shallow='--depth 2' || shallow=
-    git clone $shallow git://git.sv.gnu.org/gnulib ||
-      cleanup_gnulib
+      shallow=
+      if test -z "$GNULIB_REVISION"; then
+        git clone -h 2>&1 | grep -- --depth > /dev/null && shallow='--depth 2'
+        git clone $shallow ${GNULIB_URL:-$default_gnulib_url} "$gnulib_path" \
+          || cleanup_gnulib
+      else
+        git fetch -h 2>&1 | grep -- --depth > /dev/null && shallow='--depth 2'
+        mkdir -p "$gnulib_path"
+        # Only want a shallow checkout of $GNULIB_REVISION, but git does not
+        # support cloning by commit hash. So attempt a shallow fetch by commit
+        # hash to minimize the amount of data downloaded and changes needed to
+        # be processed, which can drastically reduce download and processing
+        # time for checkout. If the fetch by commit fails, a shallow fetch can
+        # not be performed because we do not know what the depth of the commit
+        # is without fetching all commits. So fallback to fetching all commits.
+        git -C "$gnulib_path" init
+        git -C "$gnulib_path" remote add origin \
+            ${GNULIB_URL:-$default_gnulib_url}
+        git -C "$gnulib_path" fetch $shallow origin "$GNULIB_REVISION" \
+          || git -C "$gnulib_path" fetch origin \
+          || cleanup_gnulib
+        git -C "$gnulib_path" reset --hard FETCH_HEAD
+      fi
 
-    trap - 1 2 13 15
+      trap - 1 2 13 15
+    fi
+    GNULIB_SRCDIR=$gnulib_path
+    ;;
+  *)
+    # Use GNULIB_SRCDIR directly or as a reference.
+    if $use_git && test -d "$GNULIB_SRCDIR"/.git && \
+          git_modules_config submodule.gnulib.url >/dev/null; then
+      echo "$0: getting gnulib files..."
+      if git submodule -h|grep -- --reference > /dev/null; then
+        # Prefer the one-liner available in git 1.6.4 or newer.
+        git submodule update --init --reference "$GNULIB_SRCDIR" \
+          "$gnulib_path" || exit $?
+      else
+        # This fallback allows at least git 1.5.5.
+        if test -f "$gnulib_path"/gnulib-tool; then
+          # Since file already exists, assume submodule init already complete.
+          git submodule update -- "$gnulib_path" || exit $?
+        else
+          # Older git can't clone into an empty directory.
+          rmdir "$gnulib_path" 2>/dev/null
+          git clone --reference "$GNULIB_SRCDIR" \
+            "$(git_modules_config submodule.gnulib.url)" "$gnulib_path" \
+            && git submodule init -- "$gnulib_path" \
+            && git submodule update -- "$gnulib_path" \
+            || exit $?
+        fi
+      fi
+      GNULIB_SRCDIR=$gnulib_path
+    fi
+    ;;
+  esac
+
+  if test -d "$GNULIB_SRCDIR"/.git && test -n "$GNULIB_REVISION" \
+     && ! git_modules_config submodule.gnulib.url >/dev/null; then
+    (cd "$GNULIB_SRCDIR" && git checkout "$GNULIB_REVISION") || cleanup_gnulib
   fi
-  GNULIB_SRCDIR=gnulib
-  ;;
-*)
-  # Redirect the gnulib submodule to the directory on the command line
-  # if possible.
-  if test -d "$GNULIB_SRCDIR"/.git && \
-	git_modules_config submodule.gnulib.url >/dev/null; then
-    git submodule init
-    GNULIB_SRCDIR=`cd $GNULIB_SRCDIR && pwd`
-    git config --replace-all submodule.gnulib.url $GNULIB_SRCDIR
-    echo "$0: getting gnulib files..."
-    git submodule update || exit $?
-    GNULIB_SRCDIR=gnulib
+
+  # $GNULIB_SRCDIR now points to the version of gnulib to use, and
+  # we no longer need to use git or $gnulib_path below here.
+
+  if $bootstrap_sync; then
+    cmp -s "$0" "$GNULIB_SRCDIR/build-aux/bootstrap" || {
+      echo "$0: updating bootstrap and restarting..."
+      case $(sh -c 'echo "$1"' -- a) in
+        a) ignored=--;;
+        *) ignored=ignored;;
+      esac
+      exec sh -c \
+        'cp "$1" "$2" && shift && exec "${CONFIG_SHELL-/bin/sh}" "$@"' \
+        $ignored "$GNULIB_SRCDIR/build-aux/bootstrap" \
+        "$0" "$@" --no-bootstrap-sync
+    }
   fi
-  ;;
-esac
 
-gnulib_tool=$GNULIB_SRCDIR/gnulib-tool
-<$gnulib_tool || exit
+  gnulib_tool=$GNULIB_SRCDIR/gnulib-tool
+  <$gnulib_tool || exit $?
+fi
 
 # Get translations.
 
 download_po_files() {
   subdir=$1
   domain=$2
-  echo "$0: getting translations into $subdir for $domain..."
-  cmd=`printf "$po_download_command_format" "$domain" "$subdir"`
+  echo "$me: getting translations into $subdir for $domain..."
+  cmd=$(printf "$po_download_command_format" "$subdir" "$domain")
   eval "$cmd"
 }
 
-# Download .po files to $po_dir/.reference and copy only the new
+# Mirror .po files to $po_dir/.reference and copy only the new
 # or modified ones into $po_dir.  Also update $po_dir/LINGUAS.
+# Note po files that exist locally only are left in $po_dir but will
+# not be included in LINGUAS and hence will not be distributed.
 update_po_files() {
   # Directory containing primary .po files.
   # Overwrite them only when we're sure a .po file is new.
   po_dir=$1
   domain=$2
 
-  # Download *.po files into this dir.
+  # Mirror *.po files into this dir.
   # Usually contains *.s1 checksum files.
   ref_po_dir="$po_dir/.reference"
 
   test -d $ref_po_dir || mkdir $ref_po_dir || return
   download_po_files $ref_po_dir $domain \
     && ls "$ref_po_dir"/*.po 2>/dev/null |
-      sed 's|.*/||; s|\.po$||' > "$po_dir/LINGUAS"
+      sed 's|.*/||; s|\.po$||' > "$po_dir/LINGUAS" || return
 
-  langs=`cd $ref_po_dir && echo *.po|sed 's/\.po//g'`
+  langs=$(cd $ref_po_dir && echo *.po | sed 's/\.po//g')
   test "$langs" = '*' && langs=x
   for po in $langs; do
     case $po in x) continue;; esac
     new_po="$ref_po_dir/$po.po"
     cksum_file="$ref_po_dir/$po.s1"
     if ! test -f "$cksum_file" ||
-	! test -f "$po_dir/$po.po" ||
-	! sha1sum -c --status "$cksum_file" < "$new_po" > /dev/null; then
-      echo "updated $po_dir/$po.po..."
-      cp "$new_po" "$po_dir/$po.po" && sha1sum < "$new_po" > "$cksum_file"
+        ! test -f "$po_dir/$po.po" ||
+        ! $SHA1SUM -c "$cksum_file" < "$new_po" > /dev/null 2>&1; then
+      echo "$me: updated $po_dir/$po.po..."
+      cp "$new_po" "$po_dir/$po.po" \
+          && $SHA1SUM < "$new_po" > "$cksum_file" || return
     fi
   done
 }
@@ -341,240 +899,125 @@ case $SKIP_PO in
   fi;;
 esac
 
-symlink_to_dir()
-{
-  src=$1/$2
-  dst=${3-$2}
-
-  test -f "$src" && {
+version_controlled_file() {
+  parent=$1
+  file=$2
+  if test -d .git; then
+    git rm -n "$file" > /dev/null 2>&1
+  elif test -d .svn; then
+    svn log -r HEAD "$file" > /dev/null 2>&1
+  elif test -d CVS; then
+    grep -F "/${file##*/}/" "$parent/CVS/Entries" 2>/dev/null |
+             grep '^/[^/]*/[0-9]' > /dev/null
+  else
+    warn_ "no version control for $file?"
+    false
+  fi
+}
 
-    # If the destination directory doesn't exist, create it.
-    # This is required at least for "lib/uniwidth/cjk.h".
-    dst_dir=`dirname "$dst"`
-    if ! test -d "$dst_dir"; then
-      mkdir -p "$dst_dir"
+# NOTE: we have to be careful to run both autopoint and libtoolize
+# before gnulib-tool, since gnulib-tool is likely to provide newer
+# versions of files "installed" by these two programs.
+# Then, *after* gnulib-tool (see below), we have to be careful to
+# run autoreconf in such a way that it does not run either of these
+# two just-pre-run programs.
 
-      # If we've just created a directory like lib/uniwidth,
-      # tell version control system(s) it's ignorable.
-      # FIXME: for now, this does only one level
-      parent=`dirname "$dst_dir"`
-      for dot_ig in x $vc_ignore; do
-	test $dot_ig = x && continue
-	ig=$parent/$dot_ig
-	insert_sorted_if_absent $ig `echo "$dst_dir"|sed 's,.*/,,'`
-      done
-    fi
+# Import from gettext.
+with_gettext=yes
+grep '^[	 ]*AM_GNU_GETTEXT_VERSION(' configure.ac >/dev/null || \
+    with_gettext=no
 
-    if $copy; then
-      {
-	test ! -h "$dst" || {
-	  echo "$0: rm -f $dst" &&
-	  rm -f "$dst"
-	}
-      } &&
-      test -f "$dst" &&
-      cmp -s "$src" "$dst" || {
-	echo "$0: cp -fp $src $dst" &&
-	cp -fp "$src" "$dst"
-      }
-    else
-      test -h "$dst" &&
-      src_ls=`ls -diL "$src" 2>/dev/null` && set $src_ls && src_i=$1 &&
-      dst_ls=`ls -diL "$dst" 2>/dev/null` && set $dst_ls && dst_i=$1 &&
-      test "$src_i" = "$dst_i" || {
-	dot_dots=
-	case $src in
-	/*) ;;
-	*)
-	  case /$dst/ in
-	  *//* | */../* | */./* | /*/*/*/*/*/)
-	     echo >&2 "$0: invalid symlink calculation: $src -> $dst"
-	     exit 1;;
-	  /*/*/*/*/)	dot_dots=../../../;;
-	  /*/*/*/)	dot_dots=../../;;
-	  /*/*/)	dot_dots=../;;
-	  esac;;
-	esac
-
-	echo "$0: ln -fs $dot_dots$src $dst" &&
-	ln -fs "$dot_dots$src" "$dst"
-      }
-    fi
-  }
-}
+if test $with_gettext = yes || test $use_libtool = 1; then
 
-cp_mark_as_generated()
-{
-  cp_src=$1
-  cp_dst=$2
+  tempbase=.bootstrap$$
+  trap "rm -f $tempbase.0 $tempbase.1" 1 2 13 15
 
-  if cmp -s "$cp_src" "$GNULIB_SRCDIR/$cp_dst"; then
-    symlink_to_dir "$GNULIB_SRCDIR" "$cp_dst"
-  elif cmp -s "$cp_src" "$local_gl_dir/$cp_dst"; then
-    symlink_to_dir $local_gl_dir "$cp_dst"
-  else
-    case $cp_dst in
-      *.[ch])             c1='/* '; c2=' */';;
-      *.texi)             c1='@c '; c2=     ;;
-      *.m4|*/Make*|Make*) c1='# ' ; c2=     ;;
-      *)                  c1=     ; c2=     ;;
-    esac
+  > $tempbase.0 > $tempbase.1 &&
+  find . ! -type d -print | sort > $tempbase.0 || exit
 
-    # If the destination directory doesn't exist, create it.
-    # This is required at least for "lib/uniwidth/cjk.h".
-    dst_dir=`dirname "$cp_dst"`
-    test -d "$dst_dir" || mkdir -p "$dst_dir"
-
-    if test -z "$c1"; then
-      cmp -s "$cp_src" "$cp_dst" || {
-	# Copy the file first to get proper permissions if it
-	# doesn't already exist.  Then overwrite the copy.
-	echo "$0: cp -f $cp_src $cp_dst" &&
-	rm -f "$cp_dst" &&
-	cp "$cp_src" "$cp_dst-t" &&
-	sed "s!$bt_regex/!!g" "$cp_src" > "$cp_dst-t" &&
-	mv -f "$cp_dst-t" "$cp_dst"
-      }
-    else
-      # Copy the file first to get proper permissions if it
-      # doesn't already exist.  Then overwrite the copy.
-      cp "$cp_src" "$cp_dst-t" &&
-      (
-	echo "$c1-*- buffer-read-only: t -*- vi: set ro:$c2" &&
-	echo "${c1}DO NOT EDIT! GENERATED AUTOMATICALLY!$c2" &&
-	sed "s!$bt_regex/!!g" "$cp_src"
-      ) > $cp_dst-t &&
-      if cmp -s "$cp_dst-t" "$cp_dst"; then
-	rm -f "$cp_dst-t"
-      else
-	echo "$0: cp $cp_src $cp_dst # with edits" &&
-	mv -f "$cp_dst-t" "$cp_dst"
-      fi
-    fi
+  if test $with_gettext = yes; then
+    # Released autopoint has the tendency to install macros that have been
+    # obsoleted in current gnulib, so run this before gnulib-tool.
+    echo "$0: $AUTOPOINT --force"
+    $AUTOPOINT --force || exit
   fi
-}
 
-version_controlled_file() {
-  dir=$1
-  file=$2
-  found=no
-  if test -d CVS; then
-    grep -F "/$file/" $dir/CVS/Entries 2>/dev/null |
-	     grep '^/[^/]*/[0-9]' > /dev/null && found=yes
-  elif test -d .git; then
-    git rm -n "$dir/$file" > /dev/null 2>&1 && found=yes
-  elif test -d .svn; then
-    svn log -r HEAD "$dir/$file" > /dev/null 2>&1 && found=yes
-  else
-    echo "$0: no version control for $dir/$file?" >&2
+  # Autoreconf runs aclocal before libtoolize, which causes spurious
+  # warnings if the initial aclocal is confused by the libtoolized
+  # (or worse out-of-date) macro directory.
+  # libtoolize 1.9b added the --install option; but we support back
+  # to libtoolize 1.5.22, where the install action was default.
+  if test $use_libtool = 1; then
+    install=
+    case $($LIBTOOLIZE --help) in
+      *--install*) install=--install ;;
+    esac
+    echo "running: $LIBTOOLIZE $install --copy"
+    $LIBTOOLIZE $install --copy
   fi
-  test $found = yes
-}
 
-slurp() {
-  for dir in . `(cd $1 && find * -type d -print)`; do
-    copied=
-    sep=
-    for file in `ls -a $1/$dir`; do
-      case $file in
-      .|..) continue;;
-      .*) continue;; # FIXME: should all file names starting with "." be ignored?
-      esac
-      test -d $1/$dir/$file && continue
-      for excluded_file in $excluded_files; do
-	test "$dir/$file" = "$excluded_file" && continue 2
+  find . ! -type d -print | sort >$tempbase.1
+  old_IFS=$IFS
+  IFS=$nl
+  for file in $(comm -13 $tempbase.0 $tempbase.1); do
+    IFS=$old_IFS
+    parent=${file%/*}
+    version_controlled_file "$parent" "$file" || {
+      for dot_ig in x $vc_ignore; do
+        test $dot_ig = x && continue
+        ig=$parent/$dot_ig
+        insert_vc_ignore "$ig" "${file##*/}"
       done
-      if test $file = Makefile.am; then
-        copied=$copied${sep}$gnulib_mk; sep=$nl
-	remove_intl='/^[^#].*\/intl/s/^/#/;'"s!$bt_regex/!!g"
-        sed "$remove_intl" $1/$dir/$file | cmp -s - $dir/$gnulib_mk || {
-	  echo "$0: Copying $1/$dir/$file to $dir/$gnulib_mk ..." &&
-	  rm -f $dir/$gnulib_mk &&
-	  sed "$remove_intl" $1/$dir/$file >$dir/$gnulib_mk
-	}
-      elif { test "${2+set}" = set && test -r $2/$dir/$file; } ||
-	   version_controlled_file $dir $file; then
-	echo "$0: $dir/$file overrides $1/$dir/$file"
-      else
-	copied=$copied$sep$file; sep=$nl
-	if test $file = gettext.m4; then
-	  echo "$0: patching m4/gettext.m4 to remove need for intl/* ..."
-	  rm -f $dir/$file
-	  sed '
-	    /^AC_DEFUN(\[AM_INTL_SUBDIR],/,/^]/c\
-	      AC_DEFUN([AM_INTL_SUBDIR], [
-	    /^AC_DEFUN(\[gt_INTL_SUBDIR_CORE],/,/^]/c\
-	      AC_DEFUN([gt_INTL_SUBDIR_CORE], [])
-	    $a\
-	      AC_DEFUN([gl_LOCK_EARLY], [])
-	  ' $1/$dir/$file >$dir/$file
-	else
-	  cp_mark_as_generated $1/$dir/$file $dir/$file
-	fi
-      fi || exit
-    done
-
-    for dot_ig in x $vc_ignore; do
-      test $dot_ig = x && continue
-      ig=$dir/$dot_ig
-      if test -n "$copied"; then
-	insert_sorted_if_absent $ig "$copied"
-	# If an ignored file name ends with .in.h, then also add
-	# the name with just ".h".  Many gnulib headers are generated,
-	# e.g., stdint.in.h -> stdint.h, dirent.in.h ->..., etc.
-	# Likewise for .gperf -> .h, .y -> .c, and .sin -> .sed
-	f=`echo "$copied"|sed 's/\.in\.h$/.h/;s/\.sin$/.sed/;s/\.y$/.c/;s/\.gperf$/.h/'`
-	insert_sorted_if_absent $ig "$f"
-
-	# For files like sys_stat.in.h and sys_time.in.h, record as
-	# ignorable the directory we might eventually create: sys/.
-	f=`echo "$copied"|sed 's/sys_.*\.in\.h$/sys/'`
-	insert_sorted_if_absent $ig "$f"
-      fi
-    done
+    }
   done
-}
-
+  IFS=$old_IFS
 
-# Create boot temporary directories to import from gnulib and gettext.
-rm -fr $bt $bt2 &&
-mkdir $bt $bt2 || exit
+  rm -f $tempbase.0 $tempbase.1
+  trap - 1 2 13 15
+fi
 
 # Import from gnulib.
 
-gnulib_tool_options="\
- --import\
- --no-changelog\
- --aux-dir $bt/$build_aux\
- --doc-base $bt/$doc_base\
- --lib $gnulib_name\
- --m4-base $bt/$m4_base/\
- --source-base $bt/$source_base/\
- --tests-base $bt/$tests_base\
- --local-dir $local_gl_dir\
- $gnulib_tool_option_extras\
-"
-echo "$0: $gnulib_tool $gnulib_tool_options --import ..."
-$gnulib_tool $gnulib_tool_options --import $gnulib_modules &&
-slurp $bt || exit
-
-for file in $gnulib_files; do
-  symlink_to_dir "$GNULIB_SRCDIR" $file || exit
-done
-
+if $use_gnulib; then
+  gnulib_tool_options="\
+   --no-changelog\
+   --aux-dir=$build_aux\
+   --doc-base=$doc_base\
+   --lib=$gnulib_name\
+   --m4-base=$m4_base/\
+   --source-base=$source_base/\
+   --tests-base=$tests_base\
+   --local-dir=$local_gl_dir\
+   $gnulib_tool_option_extras\
+  "
+  if test $use_libtool = 1; then
+    case "$gnulib_tool_options " in
+      *' --libtool '*) ;;
+      *) gnulib_tool_options="$gnulib_tool_options --libtool" ;;
+    esac
+  fi
+  echo "$0: $gnulib_tool $gnulib_tool_options --import ..."
+  $gnulib_tool $gnulib_tool_options --import $gnulib_modules \
+    || die "gnulib-tool failed"
 
-# Import from gettext.
-with_gettext=yes
-grep '^[	 ]*AM_GNU_GETTEXT_VERSION(' configure.ac >/dev/null || \
-    with_gettext=no
+  for file in $gnulib_files; do
+    symlink_to_dir "$GNULIB_SRCDIR" $file \
+      || die "failed to symlink $file"
+  done
+fi
 
-if test $with_gettext = yes; then
-  echo "$0: (cd $bt2; autopoint) ..."
-  cp configure.ac $bt2 &&
-  (cd $bt2 && autopoint && rm configure.ac) &&
-  slurp $bt2 $bt || exit
+bootstrap_post_import_hook \
+  || die "bootstrap_post_import_hook failed"
+
+# Don't proceed if there are uninitialized submodules.  In particular,
+# the next step will remove dangling links, which might be links into
+# uninitialized submodules.
+#
+# Uninitialized submodules are listed with an initial dash.
+if $use_git && git submodule | grep '^-' >/dev/null; then
+  die "some git submodules are not initialized. "     \
+      "Run 'git submodule update --init' and bootstrap again."
 fi
-rm -fr $bt $bt2 || exit
 
 # Remove any dangling symlink matching "*.m4" or "*.[ch]" in some
 # gnulib-populated directories.  Such .m4 files would cause aclocal to fail.
@@ -588,42 +1031,32 @@ find "$m4_base" "$source_base" \
   -depth \( -name '*.m4' -o -name '*.[ch]' \) \
   -type l -xtype l -delete > /dev/null 2>&1
 
-# Reconfigure, getting other files.
+# Invoke autoreconf with --force --install to ensure upgrades of tools
+# such as ylwrap.
+AUTORECONFFLAGS="--verbose --install --force -I $m4_base $ACLOCAL_FLAGS"
 
-aclocal_flags=`sed -n 's/ACLOCAL_AMFLAGS *=//p' Makefile.am`
-for command in \
-  libtool \
-  "aclocal --force $aclocal_flags" \
-  'autoconf --force' \
-  'autoheader --force' \
-  'automake --add-missing --copy --force-missing';
-do
-  if test "$command" = libtool; then
-    use_libtool=0
-    # We'd like to use grep -E, to see if any of LT_INIT,
-    # AC_PROG_LIBTOOL, AM_PROG_LIBTOOL is used in configure.ac,
-    # but that's not portable enough (e.g., for Solaris).
-    grep '^[	 ]*A[CM]_PROG_LIBTOOL' configure.ac >/dev/null \
-      && use_libtool=1
-    grep '^[	 ]*LT_INIT' configure.ac >/dev/null \
-      && use_libtool=1
-    test $use_libtool = 0 \
-      && continue
-    command='libtoolize -c -f'
-  fi
-  echo "$0: $command ..."
-  $command || exit
-done
+# Some systems (RHEL 5) are using ancient autotools, for which the
+# --no-recursive option had not been invented.  Detect that lack and
+# omit the option when it's not supported.  FIXME in 2017: remove this
+# hack when RHEL 5 autotools are updated, or when they become irrelevant.
+case $($AUTORECONF --help) in
+  *--no-recursive*) AUTORECONFFLAGS="$AUTORECONFFLAGS --no-recursive";;
+esac
 
+# Tell autoreconf not to invoke autopoint or libtoolize; they were run above.
+echo "running: AUTOPOINT=true LIBTOOLIZE=true $AUTORECONF $AUTORECONFFLAGS"
+AUTOPOINT=true LIBTOOLIZE=true $AUTORECONF $AUTORECONFFLAGS \
+  || die "autoreconf failed"
 
 # Get some extra files from gnulib, overriding existing files.
 for file in $gnulib_extra_files; do
   case $file in
   */INSTALL) dst=INSTALL;;
-  build-aux/*) dst=$build_aux/`expr "$file" : 'build-aux/\(.*\)'`;;
+  build-aux/*) dst=$build_aux/${file#build-aux/};;
   *) dst=$file;;
   esac
-  symlink_to_dir "$GNULIB_SRCDIR" $file $dst || exit
+  symlink_to_dir "$GNULIB_SRCDIR" $file $dst \
+    || die "failed to symlink $file"
 done
 
 if test $with_gettext = yes; then
@@ -632,13 +1065,26 @@ if test $with_gettext = yes; then
   rm -f po/Makevars
   sed '
     /^EXTRA_LOCALE_CATEGORIES *=/s/=.*/= '"$EXTRA_LOCALE_CATEGORIES"'/
-    /^MSGID_BUGS_ADDRESS *=/s/=.*/= '"$MSGID_BUGS_ADDRESS"'/
+    /^COPYRIGHT_HOLDER *=/s/=.*/= '"$COPYRIGHT_HOLDER"'/
+    /^MSGID_BUGS_ADDRESS *=/s|=.*|= '"$MSGID_BUGS_ADDRESS"'|
     /^XGETTEXT_OPTIONS *=/{
       s/$/ \\/
       a\
-	  '"$XGETTEXT_OPTIONS"' $${end_of_xgettext_options+}
+          '"$XGETTEXT_OPTIONS"' $${end_of_xgettext_options+}
     }
-  ' po/Makevars.template >po/Makevars
+  ' po/Makevars.template >po/Makevars \
+    || die 'cannot generate po/Makevars'
+
+  # If the 'gettext' module is in use, grab the latest Makefile.in.in.
+  # If only the 'gettext-h' module is in use, assume autopoint already
+  # put the correct version of this file into place.
+  case $gnulib_modules in
+  *gettext-h*) ;;
+  *gettext*)
+    cp $GNULIB_SRCDIR/build-aux/po/Makefile.in.in po/Makefile.in.in \
+      || die "cannot create po/Makefile.in.in"
+    ;;
+  esac
 
   if test -d runtime-po; then
     # Similarly for runtime-po/Makevars, but not quite the same.
@@ -648,15 +1094,26 @@ if test $with_gettext = yes; then
       /^subdir *=.*/s/=.*/= runtime-po/
       /^MSGID_BUGS_ADDRESS *=/s/=.*/= bug-'"$package"'@gnu.org/
       /^XGETTEXT_OPTIONS *=/{
-	s/$/ \\/
-	a\
-	    '"$XGETTEXT_OPTIONS_RUNTIME"' $${end_of_xgettext_options+}
+        s/$/ \\/
+        a\
+            '"$XGETTEXT_OPTIONS_RUNTIME"' $${end_of_xgettext_options+}
       }
-    ' <po/Makevars.template >runtime-po/Makevars
+    ' po/Makevars.template >runtime-po/Makevars \
+    || die 'cannot generate runtime-po/Makevars'
 
     # Copy identical files from po to runtime-po.
     (cd po && cp -p Makefile.in.in *-quot *.header *.sed *.sin ../runtime-po)
   fi
 fi
 
+bootstrap_epilogue
+
 echo "$0: done.  Now you can run './configure'."
+
+# Local Variables:
+# eval: (add-hook 'before-save-hook 'time-stamp)
+# time-stamp-start: "scriptversion="
+# time-stamp-format: "%:y-%02m-%02d.%02H"
+# time-stamp-time-zone: "UTC0"
+# time-stamp-end: "; # UTC"
+# End: