#!/usr/bin/perl -w

#########################################################################
# #
# ADDUSER Local System Additions v4.6 #
# Copyright (C) 1999-2004, John Zaitseff #
# #
#########################################################################

# Author: John Zaitseff <[email protected]>
# Date: 23rd September, 2004
# Version: 4.6

# This program, once installed as /usr/local/sbin/adduser.local, is auto-
# matically called by the adduser(8) system program on a Debian system.
# This script completes the creation of a user account in a system-
# dependent way.
#
# This script is automatically called by adduser with arguments "username
# uid gid homedir". See adduser(8) for more details. In addition, this
# script may be called manually. In this case, the following syntax
# applies:
#
# /usr/local/sbin/adduser.local [options] username [uid gid homedir]
#
# where the following options exist:
#
# --dry-run -n - Pretend to fulfil everything required, without
# doing anything.
# --quiet -q - Don't show extraneous information.
# --verbose -v - Show information about what was done (default).
# --help -h - Show a brief command-line summary.
# --version -V - Show the version of the adduser.local script.
# --conf <file> - Use configuration file <file> instead of the
# default /etc/adduser.local.conf.


# This program, including associated files, is free software. You may
# distribute it and/or modify it under the terms of the GNU General Public
# License as published by the Free Software Foundation; either Version 2
# 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, write to the Free Software Foundation, Inc.,
# 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA


#########################################################################
# Configuration parameters and default values

use strict;


(our $O = $0) =~ s,^.*/,,; # adduser.local script name (without path)
our $version = '4.6'; # Script version

our @adduser = ('/usr/sbin/adduser', '--quiet'); # adduser(8)
our @chown = ('/bin/chown'); # chown(1)
our @install = ('/usr/bin/install', '-p'); # install(1)

our $procmounts = '/proc/mounts'; # List of current mounts

our $s_false = 'false'; # False string value, in lower case
our $s_true = 'true'; # True string value, in lower case

# These default values are extensively documented in adduser.local.conf.

our $d_conffile = '/etc/adduser.local.conf'; # Configuration file location
our $d_skelother = '/etc/skel.other'; # Location of skeleton files
our $d_dirmode = '2755'; # Octal mode for directories
our $d_filemode = '0644'; # Octal mode for files

our $d_user = ''; # Default service user name
our $d_group = ''; # Default service group name
our $d_addtogroup = $s_false; # Default for addtogroup variable
our $d_homedir = ''; # Default home directory
our $d_subdir = ''; # Default subdirectory
our $d_althome = $s_false; # Default for use alternate home directory
our $d_mounted = $s_false; # Default for checking if mounted
our $d_mkdir = $s_false; # Default for creating directory
our $d_chgrpdir = $s_false; # Default for chgrpdir variable
our $d_mklink = $s_false; # Default for creating symbolic link
our $d_linkname = ''; # Default for symbolic link name
our $d_skelfile = ''; # Default for skeleton file
our $d_chgrpskel = $s_false; # Default for chgrpskel variable

# Various strings appearing in the configuration file. While they are
# case insensitive in the configuration file, they must appear in lower
# case here.

our $s_skelother = 'skelother';
our $s_dirmode = 'dirmode';
our $s_filemode = 'filemode';

our $s_service = 'service';

our $s_user = 'user';
our $s_group = 'group';
our $s_addtogroup = 'addtogroup';
our $s_homedir = 'homedir';
our $s_subdir = 'subdir';
our $s_althome = 'althome';
our $s_mounted = 'mounted';
our $s_mkdir = 'mkdir';
our $s_chgrpdir = 'chgrpdir';
our $s_mklink = 'mklink';
our $s_linkname = 'linkname';
our $s_skelfile = 'skelfile';
our $s_chgrpskel = 'chgrpskel';

our @s_false = ($s_false, 'f', 'no', 'n', '0');
our @s_true = ($s_true, 't', 'yes', 'y', '1');

# Strings internal to this program (as used by the %cv hash)

our $s_svcuid = '.svcuid'; # Storage for UID of service's user name
our $s_svcgid = '.svcgid'; # GID of service's user name or group name
our $s_actualdir = '.actualdir'; # Actual dir: homedir + subdir + username
our $s_actuallink = '.actuallink'; # Actual sym link: user homedir + linkname
our $s_actualsrcf = '.actualsrcf'; # Actual source file: skelother + skelfile
our $s_actualdstf = '.actualdstf'; # Actual dest file: actualdir + skelfile

our $s_addtogroupB = '.addtogroupB'; # Boolean versions of variables
our $s_althomeB = '.althomeB';
our $s_mountedB = '.mountedB';
our $s_mkdirB = '.mkdirB';
our $s_chgrpdirB = '.chgrpdirB';
our $s_mklinkB = '.mklinkB';
our $s_chgrpskelB = '.chgrpskelB';


#########################################################################
# Initialise global variables

our $conffile = $d_conffile; # Default configuration file
our $verbose = 1; # Be verbose by default
our $dryrun = 0; # NOT a dry run by default

our @services = (); # No services to install by default

# %cv is a hash for all configuration variables read in from the
# configuration file. Global variables are represented by their strings,
# eg, $cv{"skelother"}. Service-specific variables are represented by the
# service string value, a comma, then their string, eg, $cv{"www","user"}.
# The %cl hash plays a similar role, but contains the line number of the
# configuration.

our (%cv, %cl);

$cv{$s_skelother} = $d_skelother; $cl{$s_skelother} = 0;
$cv{$s_dirmode} = $d_dirmode; $cl{$s_dirmode} = 0;
$cv{$s_filemode} = $d_filemode; $cl{$s_filemode} = 0;

# For safety's sake, initialise the PATH environment variable

$ENV{PATH} = '/usr/sbin:/usr/bin:/sbin:/bin';

# Declare some global variables

our $username; # Username for which adduser.local was called
our $uid; # User's UID
our $gid; # User's GID
our $homedir; # User's home directory


#########################################################################
# Process command-line arguments

while ($_ = $ARGV[0]) {
last if (! /^-/);
shift @ARGV;
last if ($_ eq '--');

# Split combined short-form options into single arguments
if (/^-(\w{2,})/) {
my @args = split //, $1;

foreach my $arg (@args) {
$arg = "-$arg";
}
unshift @ARGV, @args;
next;
}

# Process command-line options
if (($_ eq '--conf') || ($_ eq '-c')) { # --conf filename
&chkparam($_);
$conffile = shift @ARGV;
}

elsif (($_ eq '--dry-run') || ($_ eq '-n')) { # --dry-run
$dryrun = 1;
}

elsif (($_ eq '--quiet') || ($_ eq '-q')) { # --quiet
$verbose = 0;
}

elsif (($_ eq '--verbose') || ($_ eq '-v')) { # --verbose
$verbose = 1;
}

elsif (($_ eq '--help') || ($_ eq '-h')) { # --help
&showusage();
exit(0);
}

elsif (($_ eq '--version') || ($_ eq '-V')) { # --version
&showversion();
exit(0);
}

else {
&showcmdlerr("Unrecognised option: $_");
}
}


#########################################################################
# Process additional command-line parameters: username [uid gid homedir]

if ($#ARGV < 0) { &showcmdlerr("Missing username parameter"); }
if ($#ARGV > 3) { &showcmdlerr("Too many command-line parameters"); }

# Include some sanity checking. These checks are not particularly
# rigorous, as root can do anything anyway... It is meant to stop silly
# mistakes, not to stop thinking. In any case, this script SHOULD only be
# called from adduser(8)...

die "$O: Only root can execute this program\n" if ($> != 0) && (! $dryrun);

if ($#ARGV == 0) {
# Only a single parameter: username

$username = $ARGV[0];

(my $t_name, my $t1, $uid, $gid, my $t2, my $t3, my $t4, $homedir)
= getpwnam($username);

die "$O: No such user: $username\n" if ! $t_name;

} elsif ($#ARGV == 3) {
# Four parameters: username uid gid homedir

$username = $ARGV[0];
$uid = $ARGV[1];
$gid = $ARGV[2];
$homedir = $ARGV[3];

$homedir =~ s,/$,,; # Remove trailing '/' if present
(my $t_name, my $t1, my $t_uid, my $t_gid) = getpwnam($username);

die "$O: No such user: $username\n" if ! $t_name;
die "$O: No such UID: $uid\n" if ! getpwuid($uid);
die "$O: No such GID: $gid\n" if ! getgrgid($gid);
die "$O: UID of user $username not the same as $uid\n" if $t_uid != $uid;
die "$O: GID of user $username not the same as $gid\n" if $t_gid != $gid;
die "$O: Directory $homedir does not exist\n" if ! -d $homedir;

} else {
&showcmdlerr("Missing uid, gid and/or homedir parameters");
}


#########################################################################
# Process the configuration file

if (! -r $conffile) {
warn "$O: Cannot read configuration file $conffile:\n";
warn "$O: $conffile: $!\n";

exit(0);
}

print "Processing configuration file $conffile\n" if $verbose;

open(CONFFILE, $conffile) || die "$O: $conffile: $!\n";
while (<CONFFILE>) {
my ($var, $svc, $val);

chomp;

# Skip comments and blank lines
next if /^\s*#/ || /^\s*$/;

# Try matching a global variable with or without quotes
if ((($var, $val) = /^\s*(\w+)\s*=\s*(.*)/) == 2) {

# Remove trailing spaces and surrounding quotes
# (Technically, doing it this way is somewhat sloppy)
$val =~ s/^(.*?)\s*$/$1/;
$val =~ s/^\"(.*)\"/$1/;
$val =~ s/^\'(.*)\'/$1/;

my $lcvar = lc $var;
my $lcval = lc $val;

# Process the global variable
if ($lcvar eq $s_service) {

# Special global configuration variable "service"
my $svc = $lcval;

if (grep((lc $_) eq $svc, @services)) {
warn "$O: Service \"$val\" redefined at $conffile:$.\n";
next;
}

push @services, $val;

# Set up default values

$cv{$svc,$s_user} = $d_user;
$cv{$svc,$s_group} = $d_group;
$cv{$svc,$s_addtogroup} = $d_addtogroup;
$cv{$svc,$s_homedir} = $d_homedir;
$cv{$svc,$s_subdir} = $d_subdir;
$cv{$svc,$s_althome} = $d_althome;
$cv{$svc,$s_mounted} = $d_mounted;
$cv{$svc,$s_mkdir} = $d_mkdir;
$cv{$svc,$s_chgrpdir} = $d_chgrpdir;
$cv{$svc,$s_mklink} = $d_mklink;
$cv{$svc,$s_linkname} = $d_linkname;
$cv{$svc,$s_skelfile} = $d_skelfile;
$cv{$svc,$s_chgrpskel} = $d_chgrpskel;

$cl{$svc,$s_user} = 0;
$cl{$svc,$s_group} = 0;
$cl{$svc,$s_addtogroup} = 0;
$cl{$svc,$s_homedir} = 0;
$cl{$svc,$s_subdir} = 0;
$cl{$svc,$s_althome} = 0;
$cl{$svc,$s_mounted} = 0;
$cl{$svc,$s_mkdir} = 0;
$cl{$svc,$s_chgrpdir} = 0;
$cl{$svc,$s_mklink} = 0;
$cl{$svc,$s_linkname} = 0;
$cl{$svc,$s_skelfile} = 0;
$cl{$svc,$s_chgrpskel} = 0;
}
else {
# Ordinary global variable

if (! defined($cv{$lcvar})) {
warn "$O: Unknown global variable \"$var\" at $conffile:$.\n";
next;
}

$cv{$lcvar} = $val;
$cl{$lcvar} = $.;
}
}

# Try matching a service variable with or without quotes
elsif ((($var, $svc, $val) = /^\s*(\w+)\s*\[\s*(\w+)\s*\]\s*=\s*(.*)/) == 3) {

# Remove trailing spaces and surrounding quotes
$val =~ s/^(.*?)\s*$/$1/;
$val =~ s/^\"(.*)\"/$1/;
$val =~ s/^\'(.*)\'/$1/;

my $lcvar = lc $var;
my $lcsvc = lc $svc;

if (! grep((lc $_) eq $lcsvc, @services)) {
warn "$O: Undefined service \"$svc\" at $conffile:$.\n";
next;
}
if (! defined($cv{$lcsvc,$lcvar})) {
warn "$O: Unknown service variable \"$var\" at $conffile:$.\n";
next;
}

$cv{$lcsvc,$lcvar} = $val;
$cl{$lcsvc,$lcvar} = $.;
}

# Otherwise, it is an error in the configuration file
else {
warn "$O: Could not parse $conffile:$.\n";
next;
}
}

close(CONFFILE) || die "$O: $conffile: $!\n";


#########################################################################
# Global variables sanity checking
{
my $t;

# Check "skelother"

if (! -d $cv{$s_skelother}) {
warn "$O: Directory $cv{$s_skelother} does not exist\n";
}

# Check "dirmode"

$t = $cv{$s_dirmode};
if (($t !~ /^[01234567]{1,4}$/) || (oct($t) == 0)) {
warn "$O: Illegal value \"$t\" at $conffile:$cl{$s_dirmode}\n";
warn "$O: Global variable \"$s_dirmode\" set to $d_dirmode\n";
$cv{$s_dirmode} = $d_dirmode;
}

# Check "filemode"

$t = $cv{$s_filemode};
if (($t !~ /^[01234567]{1,4}$/) || (oct($t) == 0)) {
warn "$O: Illegal value \"$t\" at $conffile:$cl{$s_filemode}\n";
warn "$O: Global variable \"$s_filemode\" set to $d_filemode\n";
$cv{$s_filemode} = $d_filemode;
}
}


#########################################################################
# Actually perform what is required, with appropriate error checking

foreach my $service (@services) {

my $svc = lc $service;
my ($t_user, $t_group, $t_homedir);

print "Processing service \"$service\"\n" if $verbose;

# Check validity of all boolean variables and convert them to true bools

# Note that the notation $hash{$idx1,$idx2} is exactly the same as the
# expression $hash{$idx1 . $; . $idx2}. It is for this reason that
# $svcc is defined.

my $svcc = $svc . $;; # $svc concatenated with $; ($SUBSEP)

&chkbool($svcc.$s_addtogroup, $svcc.$s_addtogroupB, $d_addtogroup, "$s_addtogroup\[$service\]");
&chkbool($svcc.$s_althome, $svcc.$s_althomeB, $d_althome, "$s_althome\[$service\]");
&chkbool($svcc.$s_mounted, $svcc.$s_mountedB, $d_mounted, "$s_mounted\[$service\]");
&chkbool($svcc.$s_mkdir, $svcc.$s_mkdirB, $d_mkdir, "$s_mkdir\[$service\]");
&chkbool($svcc.$s_chgrpdir, $svcc.$s_chgrpdirB, $d_chgrpdir, "$s_chgrpdir\[$service\]");
&chkbool($svcc.$s_mklink, $svcc.$s_mklinkB, $d_mklink, "$s_mklink\[$service\]");
&chkbool($svcc.$s_chgrpskel, $svcc.$s_chgrpskelB, $d_chgrpskel, "$s_chgrpskel\[$service\]");

# Process the "user" configuration variable

if ($cv{$svc,$s_user} ne '') {
# Retrieve information about the specified service's user name

(my $t_user, my $t1, $cv{$svc,$s_svcuid}, $cv{$svc,$s_svcgid},
my $t2, my $t3, my $t4, my $t_homedir)
= getpwnam $cv{$svc,$s_user};

if (! $t_user) {
warn "$O: Illegal user name \"$cv{$svc,$s_user}\" at $conffile:$cl{$svc,$s_user}\n";
} else {
$cv{$svc,$s_user} = $t_user;
}

# Only set home directory information if not specified by user
if ($cv{$svc,$s_homedir} eq '') {
if ($cv{$svc,$s_althomeB}) {
$cv{$svc,$s_homedir} = $homedir; # From command line
} else {
$cv{$svc,$s_homedir} = $t_homedir; # From service's home
}
}

# If the group parameter is not specified, get the appropriate info
# from the user information
if ($cv{$svc,$s_svcgid} && ($cv{$svc,$s_group} eq '')) {
($cv{$svc,$s_group}) = getgrgid $cv{$svc,$s_svcgid};
}
}

# Process the "group" configuration variable

if ($cv{$svc,$s_group} ne '') {
# Retrieve info about the group. Yes, it may have been done
# above, but specifying "group" can be done without specifying
# "user". In addition, a different group can be specified from
# that used by "user".

($t_group, my $t1, $cv{$svc,$s_svcgid}) = getgrnam $cv{$svc,$s_group};

if (! $t_group) {
warn "$O: Illegal group name \"$cv{$svc,$s_group}\" at $conffile:$cl{$svc,$s_group}\n";

$cv{$svc,$s_addtogroup} = $s_false; $cv{$svc,$s_addtogroupB} = 0;
$cv{$svc,$s_chgrpdir} = $s_false; $cv{$svc,$s_chgrpdirB} = 0;
$cv{$svc,$s_chgrpskel} = $s_false; $cv{$svc,$s_chgrpskelB} = 0;
}
else {
$cv{$svc,$s_group} = $t_group;
}
}

# Process the "addtogroup" configuration variable

if ($cv{$svc,$s_addtogroupB} && ($cv{$svc,$s_group} ne '')) {

my $t = $cv{$svc,$s_group};
(my $t_group, my $t1, my $t_gid, my $t_members) = getgrnam $t;

# Check if the user is already a member of that group

if (($t_gid == $gid) || grep($_ eq $username, split(' ', $t_members))) {
print " User \"$username\" already in group \"$t\"\n"
if $verbose;
} else {
print " Adding user \"$username\" to group \"$t\"\n"
if $verbose;
system(@adduser, $username, $t) if ! $dryrun;
}
}

# Process the "mounted" configuration variable

$cv{$svc,$s_homedir} =~ s,/$,,; # Remove trailing / on homedir
$cv{$svc,$s_subdir} =~ s,^/,,; # Remove leading / on subdir
$cv{$svc,$s_subdir} =~ s,/$,,; # Remove trailing / on subdir

if (($cv{$svc,$s_homedir} ne '') && $cv{$svc,$s_mountedB}) {
# Need to check for "mounted" before checking for the existence of
# of the service's home directory.

if (! -r $procmounts) {
warn "$O: $procmounts: $!\n";
} else {
my ($t_dev, $t_mntpoint, $t_type, $t_options);
my $ismounted = 0;
my $t_dir = $cv{$svc,$s_homedir} . '/';

# Open mounts table and process it

open(MOUNTS, $procmounts) || die "$O: $procmounts: $!\n";
while (<MOUNTS>) {
chomp;
($t_dev, $t_mntpoint, $t_type, $t_options) = split;
if ($t_mntpoint !~ m,/$,) { $t_mntpoint .= '/'; }

# Check if the service's home directory is mounted
# Skip "/" as that is always mounted
if (($t_mntpoint ne '/') &&
(substr($t_dir, 0, length($t_mntpoint))
eq $t_mntpoint)) {
$ismounted = 1;
}
}
close(MOUNTS) || die "$O: $procmounts: $!\n";

if (! $ismounted) {
print " Directory $cv{$svc,$s_homedir} not mounted\n"
if $verbose;
$cv{$svc,$s_homedir} = '';
}
}
}

# Process the "homedir" and "subdir" configuration variables

if ($cv{$svc,$s_homedir} ne '') {
if (! -d $cv{$svc,$s_homedir}) {
warn "$O: Directory $cv{$svc,$s_homedir} does not exist\n";
$cv{$svc,$s_homedir} = '';
}
elsif (($cv{$svc,$s_subdir} ne '') && (! $cv{$svc,$s_althomeB})) {
my $t = $cv{$svc,$s_homedir} . '/' . $cv{$svc,$s_subdir};
if (! -d $t) {
warn "$O: Directory $t does not exist\n";
$cv{$svc,$s_subdir} = '';
$cv{$svc,$s_homedir} = '';
}
}
}

# Calculate the actual directory to create (if necessary)

if ($cv{$svc,$s_homedir} ne '') {
$cv{$svc,$s_actualdir} = $cv{$svc,$s_homedir};
if ($cv{$svc,$s_subdir} ne '') {
$cv{$svc,$s_actualdir} .= '/' . $cv{$svc,$s_subdir};
}
if (! $cv{$svc,$s_althomeB}) {
$cv{$svc,$s_actualdir} .= '/' . $username;
}
}

# Process the "mkdir" and "chgrpdir" configuration variables

if (($cv{$svc,$s_homedir} ne '') && $cv{$svc,$s_mkdirB}) {
my $t = $cv{$svc,$s_actualdir};

if (-d $t) {
print " Directory $t already exists\n" if $verbose;
} elsif (-e $t) {
warn "$O: $t is not a directory\n";
$cv{$svc,$s_homedir} = '';
} else {
print " Directory $t created\n" if $verbose;
mkdir($t, oct($cv{$s_dirmode})) if ! $dryrun;
# Note that this newly-created directory will inherit the
# SGID (set group ID) bit from its parent directory. This
# IS desired, hence, do NOT do a separate chmod()!
if ($cv{$svc,$s_chgrpdirB}) {
chown($uid, $cv{$svc,$s_svcgid}, $t) if ! $dryrun;
} else {
chown($uid, $gid, $t) if ! $dryrun;
}
}
}

# Process the "mklink" and "linkname" configuration variables

if (($cv{$svc,$s_homedir} ne '') && $cv{$svc,$s_mklinkB}
&& (-d $cv{$svc,$s_actualdir})) {

# Calculate the actual link name

$cv{$svc,$s_linkname} =~ s,/$,,; # Remove trailing '/'

if ($cv{$svc,$s_linkname} eq '') {
$cv{$svc,$s_actuallink} = $homedir . '/' . $service;
} else {
$cv{$svc,$s_actuallink} = $homedir . '/' . $cv{$svc,$s_linkname};
}

# Create the symbolic link, if needed

my $t = $cv{$svc,$s_actuallink};
if (-l $t) {
print " Symbolic link $t already exists\n"
if $verbose;
} elsif (-e $t) {
warn "$O: $t is not a symbolic link\n";
} else {
print " Symbolic link $t created\n" if $verbose;
symlink($cv{$svc,$s_actualdir}, $t) if ! $dryrun;
if ($cv{$svc,$s_chgrpdirB}) {
&lchown($uid, $cv{$svc,$s_svcgid}, $t) if ! $dryrun;
} else {
&lchown($uid, $gid, $t) if ! $dryrun;
}
# Note that chown can NOT be used on Linux versions 2.1.81
# or later, as it changes the ownership of the TARGET of
# the symbolic link.
}
}

# Process the "skelfile" and "chgrpskel" configuration variables

if (($cv{$svc,$s_homedir} ne '') && ($cv{$svc,$s_skelfile} ne '')
&& (-d $cv{$svc,$s_actualdir})) {

my $t = $cv{$svc,$s_skelfile};
$cv{$svc,$s_actualsrcf} = $cv{$s_skelother} . '/' . $t;
$cv{$svc,$s_actualdstf} = $cv{$svc,$s_actualdir} . '/' . $t;

if (-e $cv{$svc,$s_actualdstf}) {
print " File $cv{$svc,$s_actualdstf} already exists\n"
if $verbose;
} elsif (! -r $cv{$svc,$s_actualsrcf}) {
warn "$O: $cv{$svc,$s_actualsrcf}: $!\n";
} else {
print " File $cv{$svc,$s_actualdstf} created\n" if $verbose;
if ($cv{$svc,$s_chgrpskelB}) {
system(@install, '-m', $cv{$s_filemode}, '-o', $uid,
'-g', $cv{$svc,$s_svcgid},
$cv{$svc,$s_actualsrcf}, $cv{$svc,$s_actualdstf})
if ! $dryrun;
} else {
system(@install, '-m', $cv{$s_filemode}, '-o', $uid, '-g',
$gid, $cv{$svc,$s_actualsrcf}, $cv{$svc,$s_actualdstf})
if ! $dryrun;
}
}
}
}


#########################################################################
# End of program

exit(0);


#########################################################################
# Show an error message relating to the command-line and terminate

sub showcmdlerr {
if (@_) {
foreach my $line (@_) {
warn "$O: $line\n";
}
}

die "\nUsage:\n" .
" $0 [--dry-run] [--conf filename]\n" .
" [--quiet] [--verbose] [--help] [--version] [-nqvhV]\n" .
" username [uid gid homedir]\n";
}


#########################################################################
# Check that the next argument is a valid parameter

sub chkparam ($) {
my $arg = $_[0];
if (! $ARGV[0] || ($ARGV[0] =~ /^-/)) {
&showcmdlerr("Missing argument for $arg");
}
}


#########################################################################
# Check that the configuration variable contains is a valid boolean value

sub chkbool ($$$$) {
my $var = $_[0]; # Hash key of variable to check
my $new = $_[1]; # Hash key of new variable, a true boolean
my $def = $_[2]; # Default value, in case of error
my $pvar = $_[3]; # Config. variable name (for warnings)

my $val = lc $cv{$var};

if (grep($_ eq $val, @s_true)) {
$cv{$new} = 1;
} elsif (grep($_ eq $val, @s_false)) {
$cv{$new} = 0;
} else {
warn "$O: Illegal value \"$cv{$var}\" at $conffile:$cl{$var}\n";
warn "$O: Variable \"$pvar\" set to $def\n";

$cv{$var} = $def;
&chkbool($var, $new, $def, $pvar);
}
}


#########################################################################
# A chown() that works with symbolic links

sub lchown {
# The chown() function does NOT change the ownership of symbolic links
# under Linux 2.1.81 or later. Hence, make an external call to the
# chown(1) program. This program MUST support the "-h" parameter.

my $t_uid = shift;
my $t_gid = shift;

system(@chown, '-h', "$t_uid:$t_gid", @_);
}


#########################################################################
# Display usage information

sub showusage () {
print <<"DATAEND"

$O v$version --- adduser(8) local system additions.
Copyright (C) 1999-2004, John Zaitseff.

This program, once installed as /usr/local/sbin/adduser.local, is auto-
matically called by the adduser(8) system program on a Debian system.
This script completes the creation of a user account in a system-
dependent way.

This script is automatically called by adduser with arguments \"username
uid gid homedir\". See adduser(8) for more details. In addition, this
script may be called manually. In this case, the following syntax
applies:

/usr/local/sbin/adduser.local [options] username [uid gid homedir]

where the following options exist:

--dry-run -n - Pretend to fulfil everything required, without
doing anything.
--quiet -q - Don\'t show extraneous information.
--verbose -v - Show information about what was done (default).
--help -h - Show a brief command-line summary.
--version -V - Show the version of the adduser.local script.
--conf <file> - Use configuration file <file> instead of the
default $d_conffile.

DATAEND

}


#########################################################################
# Display program version information

sub showversion () {
print <<"DATAEND"

$O v$version --- adduser(8) local system additions.
Copyright (C) 1999-2004, John Zaitseff.

This program, including associated files, is distributed under the GNU General
Public License. See /usr/share/common-licenses/GPL for more information.

DATAEND

}