tar: fix current_block confusion

[thirdparty/tar.git] / bootstrap

#! /bin/sh
# DO NOT EDIT! GENERATED AUTOMATICALLY!

# Bootstrap this package from checked-out sources.

scriptversion=2022-12-27.07; # UTC

# Copyright (C) 2003-2024 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
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 <https://www.gnu.org/licenses/>.

# Originally written by Paul Eggert.  The canonical version of this
# script is maintained as top/bootstrap in gnulib. However, to be
# useful to your package, you should place a copy of it under version
# control in the top-level directory of your package.  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.

me="$0"
medir=`dirname "$me"`

# Read the function library and the configuration.

# A library of shell functions for autopull.sh, autogen.sh, and bootstrap.

scriptlibversion=2023-06-06.21; # UTC

# Copyright (C) 2003-2024 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
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 <https://www.gnu.org/licenses/>.

# Originally written by Paul Eggert.  The canonical version of this
# script is maintained as top/bootstrap-funclib.sh in gnulib.  However,
# to be useful to your package, you should place a copy of it under
# version control in the top-level directory of your package.  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.

nl='
'

# Ensure file names are sorted consistently across platforms.
LC_ALL=C
export LC_ALL

# Honor $PERL, but work even if there is none.
PERL="${PERL-perl}"

default_gnulib_url=https://git.savannah.gnu.org/git/gnulib.git

# Copyright year, for the --version output.
copyright_year=`echo "$scriptlibversion" | 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. ------------------------------

# Directory that contains package-specific gnulib modules and/or overrides.
local_gl_dir=gl

# Name of the Makefile.am
# XXX Not used.
gnulib_mk=gnulib.mk

# List of gnulib modules needed.
gnulib_modules=

# Any gnulib files needed that are not in modules.
gnulib_files=

# 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 at the end of autopull.sh.
# Override it via your own definition in bootstrap.conf.
bootstrap_post_pull_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=\
"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//\1/
       s/[],)].*//
       p
       q
     }
     s/[],)].*//
     s/^GNU //
     y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/
     s/[^abcdefghijklmnopqrstuvwxyz0123456789_]/-/g
     p
  }
'
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
source_base=lib
m4_base=m4
doc_base=doc
tests_base=tests
gnulib_extra_files="
        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.
gnulib_tool_option_extras=

# Other locale categories that need message catalogs.
EXTRA_LOCALE_CATEGORIES=

# Additional xgettext options to use.  Use "\\\newline" to break lines.
XGETTEXT_OPTIONS='\\\
 --flag=_:1:pass-c-format\\\
 --flag=N_:1:pass-c-format\\\
 --flag=error:3:c-format --flag=error_at_line:5:c-format\\\
'

# 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.
# XXX Not used.
excluded_files=

# File that should exist in the top directory of a checked out hierarchy,
# but not in a distribution tarball.
checkout_only_file=README-hacking

# Set this to '.cvsignore .gitignore' in bootstrap.conf if you want
# those files to be generated in directories like lib/, m4/, and po/.
# Or set it to 'auto' to make this script select which to use based
# 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

# Override the default configuration, if necessary.
# Make sure that bootstrap.conf is sourced from the current directory
# if we were invoked as "sh bootstrap".
conffile=`dirname "$me"`/bootstrap.conf
test -r "$conffile" && . "$conffile"

# ------------------------- Build-time prerequisites -------------------------

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
}

# 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 "%s\n%s\n" "$p1" "$p2" | 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 "$app" = libtool; then
      app=libtoolize
    fi
    # Exempt git if git is not needed.
    if test "$app" = git; then
      $check_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
    # preexisting 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
}

# check_build_prerequisites check_git
check_build_prerequisites()
{
  check_git="$1"

  # 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 '%s' "$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
}

# 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"
}

# --------------------- Preparing GNULIB_SRCDIR for use. ---------------------
# This is part of autopull.sh, but bootstrap needs it too, for self-upgrading.

cleanup_gnulib() {
  status=$?
  # XXX It's a bad idea to erase the submodule directory if it contains local
  #     modifications.
  rm -fr "$gnulib_path"
  exit $status
}

git_modules_config () {
  test -f .gitmodules && git config --file .gitmodules "$@"
}

prepare_GNULIB_SRCDIR ()
{
  if test -n "$GNULIB_SRCDIR"; then
    # Use GNULIB_SRCDIR directly.
    # We already checked that $GNULIB_SRCDIR references a directory.
    # Verify that it contains a gnulib checkout.
    test -f "$GNULIB_SRCDIR/gnulib-tool" \
      || die "Error: --gnulib-srcdir or \$GNULIB_SRCDIR is specified, but does not contain gnulib-tool"
  elif $use_git; then
    gnulib_path=$(git_modules_config submodule.gnulib.path)
    test -z "$gnulib_path" && gnulib_path=gnulib

    # Get gnulib files.  Populate $gnulib_path, possibly updating a
    # submodule, for use in the rest of the script.

    if test -n "$GNULIB_REFDIR" && test -d "$GNULIB_REFDIR"/.git \
       && git_modules_config submodule.gnulib.url >/dev/null; then
      # Use GNULIB_REFDIR as a reference.
      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_REFDIR" \
          "$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 "$GNULIB_REFDIR" \
            "$(git_modules_config submodule.gnulib.url)" "$gnulib_path" \
            && git submodule init -- "$gnulib_path" \
            && git submodule update -- "$gnulib_path" \
            || exit $?
        fi
      fi
    else
      # GNULIB_REFDIR is not set or not usable. Ignore it.
      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_path" ]; then
        echo "$0: getting gnulib files..."

        trap cleanup_gnulib HUP INT PIPE TERM

        shallow=
        if test -z "$GNULIB_REVISION"; then
          if git clone -h 2>&1 | grep -- --depth > /dev/null; then
            shallow='--depth 2'
          fi
          git clone $shallow ${GNULIB_URL:-$default_gnulib_url} "$gnulib_path" \
            || cleanup_gnulib
        else
          if git fetch -h 2>&1 | grep -- --depth > /dev/null; then
            shallow='--depth 2'
          fi
          mkdir -p "$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 - HUP INT PIPE TERM
      fi
    fi
    GNULIB_SRCDIR=$gnulib_path
    # Verify that the submodule contains a gnulib checkout.
    test -f "$gnulib_path/gnulib-tool" \
      || die "Error: $gnulib_path is supposed to contain a gnulib checkout, but does not contain gnulib-tool"
  fi

  # XXX Should this be done if $use_git is false?
  if test -d "$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 now points to the version of gnulib to use, and
  # we no longer need to use git or $gnulib_path below here.
}

# -------- Upgrading bootstrap to the version found in GNULIB_SRCDIR. --------

upgrade_bootstrap ()
{
  if test -f "$medir"/bootstrap-funclib.sh; then
    update_lib=true
    { cmp -s "$medir"/bootstrap "$GNULIB_SRCDIR/top/bootstrap" \
      && cmp -s "$medir"/bootstrap-funclib.sh "$GNULIB_SRCDIR/top/bootstrap-funclib.sh" \
      && cmp -s "$medir"/autopull.sh "$GNULIB_SRCDIR/top/autopull.sh" \
      && cmp -s "$medir"/autogen.sh "$GNULIB_SRCDIR/top/autogen.sh"; \
    }
  else
    update_lib=false
    cmp -s "$medir"/bootstrap "$GNULIB_SRCDIR/build-aux/bootstrap"
  fi || {
    if $update_lib; then
      echo "$0: updating bootstrap & companions and restarting..."
    else
      echo "$0: updating bootstrap and restarting..."
    fi
    case $(sh -c 'echo "$1"' -- a) in
      a) ignored=--;;
      *) ignored=ignored;;
    esac
    exec sh -c \
      '{ if '$update_lib' && test -f "$1"; then cp "$1" "$3"; else cp "$2" "$3"; fi; } && { if '$update_lib' && test -f "$4"; then cp "$4" "$5"; else rm -f "$5"; fi; } && { if '$update_lib' && test -f "$6"; then cp "$6" "$7"; else rm -f "$7"; fi; } && { if '$update_lib' && test -f "$8"; then cp "$8" "$9"; else rm -f "$9"; fi; } && shift && shift && shift && shift && shift && shift && shift && shift && shift && exec "${CONFIG_SHELL-/bin/sh}" "$@"' \
      $ignored \
      "$GNULIB_SRCDIR/top/bootstrap" "$GNULIB_SRCDIR/build-aux/bootstrap" "$medir/bootstrap" \
      "$GNULIB_SRCDIR/top/bootstrap-funclib.sh" "$medir/bootstrap-funclib.sh" \
      "$GNULIB_SRCDIR/top/autopull.sh" "$medir/autopull.sh" \
      "$GNULIB_SRCDIR/top/autogen.sh" "$medir/autogen.sh" \
      "$0" "$@" --no-bootstrap-sync
  }
}

# ----------------------------------------------------------------------------

if test x"$gnulib_modules$gnulib_files$gnulib_extra_files" = x; then
  use_gnulib=false
else
  use_gnulib=true
fi

# -------- Fetch auxiliary files from the network.  --------------------------

autopull_usage() {
  cat <<EOF
Usage: $me [OPTION]...
Bootstrap this package from the checked-out sources.

Optional environment variables:
  GNULIB_SRCDIR            Specifies the local directory where gnulib
                           sources reside.  Use this if you already
                           have gnulib sources on your machine, and
                           you want to use these sources.
  GNULIB_REFDIR            Specifies the local directory where a gnulib
                           repository (with a .git subdirectory) resides.
                           Use this if you already have gnulib sources
                           and history on your machine, and do not want
                           to waste your bandwidth downloading them again.
  GNULIB_URL               Cloneable URL of the gnulib repository.

Options:
  --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
  --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 or the --gnulib-srcdir option
                           points to a gnulib repository with the correct
                           revision
  --skip-po                do not download po files
EOF
  bootstrap_print_option_usage_hook
  cat <<EOF
If the file bootstrap.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 the environment variable GNULIB_SRCDIR is set (either as an
   environment variable or via the --gnulib-srcdir option), then sources
   are fetched from that local directory.  If it is a git repository and
   the configuration variable GNULIB_REVISION is set in bootstrap.conf,
   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.  If GNULIB_REFDIR is set (either
   as an environment variable or via the --gnulib-refdir option) and is
   a git repository, then it is used as a reference.

 * 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 the configuration variable GNULIB_REVISION is set in bootstrap.conf,
   then that revision is checked out.

 * Otherwise, the existing Gnulib sources in the 'gnulib' directory are
   used.  If it is a git repository and the configuration variable
   GNULIB_REVISION is set in bootstrap.conf, 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 bootstrap.conf.

Running without arguments will suffice in most cases.
EOF
}

# Fetch auxiliary files that are omitted from the version control
# repository of this package.
autopull()
{
  # 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

  # Parse options.

  # Use git to update gnulib sources
  use_git=true

  for option
  do
    case $option in
    --help)
      autopull_usage
      return;;
    --version)
      set -e
      echo "autopull.sh $scriptlibversion"
      echo "$copyright"
      return 0
      ;;
    --skip-po)
      SKIP_PO=t;;
    --force)
      checkout_only_file=;;
    --bootstrap-sync)
      bootstrap_sync=true;;
    --no-bootstrap-sync)
      bootstrap_sync=false;;
    --no-git)
      use_git=false;;
    *)
      bootstrap_option_hook $option || die "$option: unknown option";;
    esac
  done

  $use_git || test -n "$GNULIB_SRCDIR" \
    || die "Error: --no-git requires \$GNULIB_SRCDIR environment variable or --gnulib-srcdir option"
  test -z "$GNULIB_SRCDIR" || test -d "$GNULIB_SRCDIR" \
    || die "Error: \$GNULIB_SRCDIR environment variable or --gnulib-srcdir option is specified, but does not denote a directory"

  if test -n "$checkout_only_file" && test ! -r "$checkout_only_file"; then
    die "Running this script from a non-checked-out distribution is risky."
  fi

  check_build_prerequisites $use_git

  if $use_gnulib || $bootstrap_sync; then
    prepare_GNULIB_SRCDIR
    if $bootstrap_sync; then
      upgrade_bootstrap
    fi
  fi

  # 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

  # See if we can use gnulib's git-merge-changelog merge driver.
  if $use_git && test -d .git && check_exists git; then
    if git config merge.merge-changelog.driver >/dev/null ; then
      :
    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 "$0: consider installing git-merge-changelog from gnulib"
    fi
  fi

  case $SKIP_PO in
  '')
    if test -d po; then
      update_po_files po $package || return
    fi

    if test -d runtime-po; then
      update_po_files runtime-po $package-runtime || return
    fi;;
  esac

  # ---------------------------------------------------------------------------

  bootstrap_post_pull_hook \
    || die "bootstrap_post_pull_hook failed"

  # Don't proceed if there are uninitialized submodules.  In particular,
  # autogen.sh will remove dangling links, which might be links into
  # uninitialized submodules.
  # But it's OK if the 'gnulib' submodule is uninitialized, as long as
  # GNULIB_SRCDIR is set.
  if $use_git; then
    # Uninitialized submodules are listed with an initial dash.
    uninitialized=`git submodule | grep '^-' | awk '{ print $2 }'`
    if test -n "$GNULIB_SRCDIR"; then
      uninitialized=`echo "$uninitialized" | grep -v '^gnulib$'`
    fi
    if test -n "$uninitialized"; then
      die "Some git submodules are not initialized: "`echo "$uninitialized" | tr '\n' ',' | sed -e 's|,$|.|'`" Either use option '--no-git', or run 'git submodule update --init' and bootstrap again."
    fi
  fi

  if test -f "$medir"/autogen.sh; then
    echo "$0: done.  Now you can run '$medir/autogen.sh'."
  fi
}

# ----------------------------- Get translations. -----------------------------

download_po_files() {
  subdir=$1
  domain=$2
  echo "$me: getting translations into $subdir for $domain..."
  cmd=$(printf "$po_download_command_format" "$subdir" "$domain")
  eval "$cmd"
}

# 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

  # 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" || return

  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" ||
        ! $SHA1SUM -c "$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
}

# -------- Generate files automatically from existing sources.  --------------

autogen_usage() {
  cat <<EOF
Usage: $me [OPTION]...
Bootstrap this package from the checked-out sources.

Optional environment variables:
  GNULIB_SRCDIR            Specifies the local directory where gnulib
                           sources reside.  Use this if you already
                           have gnulib sources on your machine, and
                           you want to use these sources.

Options:
  --copy                   copy files instead of creating symbolic links
  --force                  attempt to bootstrap even if the sources seem
                           not to have been checked out
EOF
  bootstrap_print_option_usage_hook
  cat <<EOF
If the file bootstrap.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 are assumed to be present:
  * in \$GNULIB_SRCDIR, if that environment variable is set,
  * otherwise, in the 'gnulib' submodule, if such a submodule is configured,
  * otherwise, in the 'gnulib' subdirectory.

Running without arguments will suffice in most cases.
EOF
}


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
}

# 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
  }
}

# Regenerate all autogeneratable files that are omitted from the
# version control repository.  In particular, regenerate all
# aclocal.m4, config.h.in, Makefile.in, configure files with new
# versions of autoconf or automake.
autogen()
{
  # 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

  # Environment variables that may be set by the user.
  : "${AUTOPOINT=autopoint}"
  : "${AUTORECONF=autoreconf}"

  if test "$vc_ignore" = auto; then
    vc_ignore=
    test -d .git && vc_ignore=.gitignore
    test -d CVS && vc_ignore="$vc_ignore .cvsignore"
  fi


  # Parse options.

  # Whether to use copies instead of symlinks.
  copy=false

  for option
  do
    case $option in
    --help)
      autogen_usage
      return;;
    --version)
      set -e
      echo "autogen.sh $scriptlibversion"
      echo "$copyright"
      return 0
      ;;
    --force)
      checkout_only_file=;;
    --copy)
      copy=true;;
    *)
      bootstrap_option_hook $option || die "$option: unknown option";;
    esac
  done

  test -z "$GNULIB_SRCDIR" || test -d "$GNULIB_SRCDIR" \
    || die "Error: \$GNULIB_SRCDIR environment variable or --gnulib-srcdir option is specified, but does not denote a directory"

  if test -n "$checkout_only_file" && test ! -r "$checkout_only_file"; then
    die "Running this script from a non-checked-out distribution is risky."
  fi

  if $use_gnulib; then
    if test -z "$GNULIB_SRCDIR"; then
      gnulib_path=$(test -f .gitmodules && git config --file .gitmodules submodule.gnulib.path)
      test -z "$gnulib_path" && gnulib_path=gnulib
      GNULIB_SRCDIR=$gnulib_path
    fi
  fi

  # Die if there is no AC_CONFIG_AUX_DIR($build_aux) line in configure.ac.
  found_aux_dir=no
  grep '^[	 ]*AC_CONFIG_AUX_DIR(\['"$build_aux"'])' configure.ac \
      >/dev/null && found_aux_dir=yes
  grep '^[	 ]*AC_CONFIG_AUX_DIR('"$build_aux"')' configure.ac \
      >/dev/null && found_aux_dir=yes
  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.
  if test ! -d $build_aux; then
    mkdir $build_aux
    for dot_ig in x $vc_ignore; do
      test $dot_ig = x && continue
      insert_vc_ignore $dot_ig $build_aux/
    done
  fi

  check_build_prerequisites false

  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

  if $use_gnulib; then
    gnulib_tool=$GNULIB_SRCDIR/gnulib-tool
    <$gnulib_tool || return
  fi

  # 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.

  # Import from gettext.
  with_gettext=yes
  grep '^[	 ]*AM_GNU_GETTEXT_VERSION(' configure.ac >/dev/null || \
      with_gettext=no

  if test $with_gettext = yes || test $use_libtool = 1; then

    tempbase=.bootstrap$$
    trap "rm -f $tempbase.0 $tempbase.1" HUP INT PIPE TERM

    > $tempbase.0 > $tempbase.1 &&
    find . ! -type d -print | sort > $tempbase.0 || return

    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 || return
    fi

    # 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

    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" "${file##*/}"
        done
      }
    done
    IFS=$old_IFS

    rm -f $tempbase.0 $tempbase.1
    trap - HUP INT PIPE TERM
  fi

  # Import from gnulib.

  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"

    for file in $gnulib_files; do
      symlink_to_dir "$GNULIB_SRCDIR" $file \
        || die "failed to symlink $file"
    done
  fi

  bootstrap_post_import_hook \
    || die "bootstrap_post_import_hook failed"

  # Remove any dangling symlink matching "*.m4" or "*.[ch]" in some
  # gnulib-populated directories.  Such .m4 files would cause aclocal to fail.
  # The following requires GNU find 4.2.3 or newer.  Considering the usual
  # portability constraints of this script, that may seem a very demanding
  # requirement, but it should be ok.  Ignore any failure, which is fine,
  # since this is only a convenience to help developers avoid the relatively
  # unusual case in which a symlinked-to .m4 file is git-removed from gnulib
  # between successive runs of this script.
  find "$m4_base" "$source_base" \
    -depth \( -name '*.m4' -o -name '*.[ch]' \) \
    -type l -xtype l -delete > /dev/null 2>&1

  # Invoke autoreconf with --force --install to ensure upgrades of tools
  # such as ylwrap.
  AUTORECONFFLAGS="--verbose --install --force -I $m4_base $ACLOCAL_FLAGS"
  AUTORECONFFLAGS="$AUTORECONFFLAGS --no-recursive"

  # 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/${file#build-aux/};;
      *) dst=$file;;
    esac
    symlink_to_dir "$GNULIB_SRCDIR" $file $dst \
      || die "failed to symlink $file"
  done

  if test $with_gettext = yes; then
    # Create gettext configuration.
    echo "$0: Creating po/Makevars from po/Makevars.template ..."
    rm -f po/Makevars
    sed '
      /^EXTRA_LOCALE_CATEGORIES *=/s/=.*/= '"$EXTRA_LOCALE_CATEGORIES"'/
      /^COPYRIGHT_HOLDER *=/s/=.*/= '"$COPYRIGHT_HOLDER"'/
      /^MSGID_BUGS_ADDRESS *=/s|=.*|= '"$MSGID_BUGS_ADDRESS"'|
      /^XGETTEXT_OPTIONS *=/{
        s/$/ \\/
        a\
            '"$XGETTEXT_OPTIONS"' $${end_of_xgettext_options+}
      }
    ' 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.
      rm -f runtime-po/Makevars
      sed '
        /^DOMAIN *=.*/s/=.*/= '"$package"'-runtime/
        /^subdir *=.*/s/=.*/= runtime-po/
        /^MSGID_BUGS_ADDRESS *=/s/=.*/= bug-'"$package"'@gnu.org/
        /^XGETTEXT_OPTIONS *=/{
          s/$/ \\/
          a\
              '"$XGETTEXT_OPTIONS_RUNTIME"' $${end_of_xgettext_options+}
        }
      ' 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: "scriptlibversion="
# time-stamp-format: "%:y-%02m-%02d.%02H"
# time-stamp-time-zone: "UTC0"
# time-stamp-end: "; # UTC"
# End:

usage() {
  cat <<EOF
Usage: $me [OPTION]...
Bootstrap this package from the checked-out sources.

Optional environment variables:
  GNULIB_SRCDIR            Specifies 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.
  GNULIB_URL               Cloneable URL of the gnulib repository.

Options:

  --pull                   Do phase 1: pull files from network
  --gen                    Do phase 2: generate from local files.
                           (The default is to do both phases.)

  --gnulib-srcdir=DIRNAME  specify the local directory where gnulib
                           sources reside.  Use this if you already
                           have gnulib sources on your machine, and
                           you want to use these sources.  Defaults
                           to \$GNULIB_SRCDIR
  --gnulib-refdir=DIRNAME  specify the local directory where a gnulib
                           repository (with a .git subdirectory) resides.
                           Use this if you already have gnulib sources
                           and history on your machine, and do not want
                           to waste your bandwidth downloading them again.
                           Defaults to \$GNULIB_REFDIR

  --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 or the --gnulib-srcdir option
                           points to a gnulib repository with the correct
                           revision
  --skip-po                do not download po files
EOF
  bootstrap_print_option_usage_hook
  cat <<EOF
If the file bootstrap.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 the environment variable GNULIB_SRCDIR is set (either as an
   environment variable or via the --gnulib-srcdir option), then sources
   are fetched from that local directory.  If it is a git repository and
   the configuration variable GNULIB_REVISION is set in bootstrap.conf,
   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.  If GNULIB_REFDIR is set (either
   as an environment variable or via the --gnulib-refdir option) and is
   a git repository, then it is used as a reference.

 * 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 the configuration variable GNULIB_REVISION is set in bootstrap.conf,
   then that revision is checked out.

 * Otherwise, the existing Gnulib sources in the 'gnulib' directory are
   used.  If it is a git repository and the configuration variable
   GNULIB_REVISION is set in bootstrap.conf, 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 bootstrap.conf.

Running without arguments will suffice in most cases.
EOF
}

# Parse options.

# Whether to pull and generate.
pull=false
gen=false

# Whether to use copies instead of symlinks.
copy=false

# Use git to update gnulib sources
use_git=true

for option
do
  case $option in
  --help)
    usage
    exit;;
  --version)
    set -e
    echo "bootstrap $scriptversion lib $scriptlibversion"
    echo "$copyright"
    exit 0
    ;;
  --pull)
    pull=true;;
  --gen)
    gen=true;;
  --gnulib-srcdir=*)
    GNULIB_SRCDIR=${option#--gnulib-srcdir=};;
  --gnulib-refdir=*)
    GNULIB_REFDIR=${option#--gnulib-refdir=};;
  --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;;
  *)
    bootstrap_option_hook $option || die "$option: unknown option";;
  esac
done

# Default is to do both.
$pull || $gen || pull=true gen=true

$use_git || test -n "$GNULIB_SRCDIR" \
  || die "Error: --no-git requires \$GNULIB_SRCDIR environment variable or --gnulib-srcdir option"
test -z "$GNULIB_SRCDIR" || test -d "$GNULIB_SRCDIR" \
  || die "Error: \$GNULIB_SRCDIR environment variable or --gnulib-srcdir option is specified, but does not denote a directory"

if test -n "$checkout_only_file" && test ! -r "$checkout_only_file"; then
  die "Bootstrapping from a non-checked-out distribution is risky."
fi

check_build_prerequisites $use_git

if $bootstrap_sync; then
  prepare_GNULIB_SRCDIR
  upgrade_bootstrap
  # Since we have now upgraded if needed, no need to try it a second time below.
  bootstrap_sync=false
fi

echo "$0: Bootstrapping from checked-out $package sources..."

# Pass GNULIB_SRCDIR and GNULIB_REFDIR to any subsidiary commands that care.
export GNULIB_SRCDIR
export GNULIB_REFDIR

if $pull && { $use_git || test -z "$SKIP_PO"; }; then
  autopull \
      `if $bootstrap_sync; then echo ' --bootstrap-sync'; else echo ' --no-bootstrap-sync'; fi` \
      `if test -z "$checkout_only_file"; then echo ' --force'; fi` \
      `if ! $use_git; then echo ' --no-git'; fi` \
      `if test -n "$SKIP_PO"; then echo ' --skip-po'; fi` \
    || die "could not fetch auxiliary files"
fi

if $gen; then
 autogen \
    `if $copy; then echo ' --copy'; fi` \
    `if test -z "$checkout_only_file"; then echo ' --force'; fi` \
  || die "could not generate auxiliary files"
fi

# ----------------------------------------------------------------------------

# 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: