path: root/examples/adduser.local

#!/usr/bin/perl -w

#########################################################################
#                                                                       #
#                  ADDUSER Local System Additions v4.9                  #
#                Copyright (C) 1999-2013, John Zaitseff                 #
#                                                                       #
#########################################################################

# Author:   John Zaitseff <J.Zaitseff@zap.org.au>
# Date:     21st June, 2013
# Version:  4.9

# 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; run "perldoc adduser.local" for more
# details.


# 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;			# Enforce better programming habits

use locale;			# Allow locale-specific sorting, etc.
use utf8;			# This script may use the UTF-8 character set
use open ":locale";		# Use locale for standard input/output

use Getopt::Long;		# Parse command line options
use Pod::Usage;			# Display command line usage


(our $O = $0)      =~ s,^.*/,,;	# Script name (without path)
our $version       = "4.9";	# Script version

our $copyright     =		# Copyright information
"$O v$version: adduser(8) local system additions\n" .
"Copyright (C) 1999-2013, John Zaitseff.\n";

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

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

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

# Strings appearing in the configuration file

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       = ('false', 'f', 'no',  'n', '0');
our @s_true        = ('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';

# Function prototypes

sub chkbool($$$$);
sub lchown(@);
sub showusage();
sub showversion();
sub showcmdlerr(@);


#########################################################################
# 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

our $opt_help;
our $opt_version;

Getopt::Long::Configure("bundling");

GetOptions('help|h|?'   => \$opt_help,
	   'version|V'  => \$opt_version,
	   'conf=s'     => \$conffile,
	   'dry-run|n!' => \$dryrun,
	   'verbose|v!' => \$verbose,
	   'quiet|q'    => sub { $verbose = 0; },
	  )
    or showcmdlerr();

showusage()   if $opt_help;
showversion() if $opt_version;


#########################################################################
# Process additional command-line parameters: USERNAME [UID GID HOMEDIR]

if ($#ARGV < 0) { showcmdlerr("$O: Missing USERNAME parameter"); }
if ($#ARGV > 3) { showcmdlerr("$O: 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) and (! $dryrun);

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

    $username = $ARGV[0];

    (my $t_name, undef, $uid, $gid, undef, undef, undef, $homedir)
	= getpwnam($username);

    die "$O: No such user: $username\n" if ! defined($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, undef, my $t_uid, my $t_gid) = getpwnam($username);

    die "$O: No such user: $username\n" if ! defined($t_name);
    die "$O: No such UID: $uid\n" if ! defined(getpwuid($uid));
    die "$O: No such GID: $gid\n" if ! defined(getgrgid($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 does not exist: $homedir\n" if ! -d $homedir;

} else {
    showcmdlerr("$O: 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, $conffile) or die "$O: $conffile: $!\n";

while (<CONFFILE>) {
    my ($var, $svc, $val);

    chomp;

    # Skip comments and blank lines
    next if /^\s*#/ or /^\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 slightly sloppy)
	$val =~ s/^(.*?)\s*$/$1/;
	$val =~ s/^\"(.*)\"$/$1/;
	$val =~ s/^\'(.*)\'$/$1/;

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

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

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

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

    # 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/;

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

	$cv{$svc,$var} = $val;
	$cl{$svc,$var} = $.;
    }

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

close(CONFFILE) or 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 (($t !~ /^[01234567]{1,4}$/) or (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 (($t !~ /^[01234567]{1,4}$/) or (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 $svc (@services) {
    my ($t_user, $t_group, $t_homedir);

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

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

    chkbool($svc, $s_addtogroup, $s_addtogroupB, $d_addtogroup);
    chkbool($svc, $s_althome,    $s_althomeB,    $d_althome);
    chkbool($svc, $s_mounted,    $s_mountedB,    $d_mounted);
    chkbool($svc, $s_mkdir,      $s_mkdirB,      $d_mkdir);
    chkbool($svc, $s_chgrpdir,   $s_chgrpdirB,   $d_chgrpdir);
    chkbool($svc, $s_mklink,     $s_mklinkB,     $d_mklink);
    chkbool($svc, $s_chgrpskel,  $s_chgrpskelB,  $d_chgrpskel);

    # Process the "user" configuration variable

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

	(my $t_user, undef, $cv{$svc,$s_svcuid}, $cv{$svc,$s_svcgid},
	 undef, undef, undef, my $t_homedir) = getpwnam($cv{$svc,$s_user});

	if (! defined($t_user)) {
	    warn "$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,$s_svcgid} and ($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, undef, $cv{$svc,$s_svcgid}) = getgrnam($cv{$svc,$s_group});

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

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

    # Process the "addtogroup" configuration variable

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

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

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

	if (($t_gid == $gid) or grep($_ 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 '') and $cv{$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, $procmounts) or die "$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 (($t_mntpoint ne '/') and
		    (substr($t_dir, 0, length($t_mntpoint)) eq $t_mntpoint)) {
		    $ismounted = 1;
		}
	    }
	    close(MOUNTS) or die "$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: No such directory: $cv{$svc,$s_homedir}\n";
	    $cv{$svc,$s_homedir} = '';
	}
	elsif (($cv{$svc,$s_subdir} ne '') and (! $cv{$svc,$s_althomeB})) {
	    my $t = $cv{$svc,$s_homedir} . '/' . $cv{$svc,$s_subdir};
	    if (! -d $t) {
		warn "$O: No such directory: $t\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 '') and $cv{$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: Not a directory: $t\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 '') and $cv{$svc,$s_mklinkB}
	and (-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 . '/' . $svc;
	} 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: Not a symbolic link: $t\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;
	    }
	}
    }

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

    if (($cv{$svc,$s_homedir} ne '') and ($cv{$svc,$s_skelfile} ne '')
	and (-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);


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

sub chkbool($$$$) {
    my $svc = $_[0];		# Service name
    my $var = $_[1];		# Partial hash key of variable to check
    my $new = $_[2];		# Partial hash key of new variable (true bool)
    my $def = $_[3];		# Default value, in case of error

    my $val = $cv{$svc,$var};

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

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


#########################################################################
# 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() {
    pod2usage(-message => $copyright, -exitval => 0);
}


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

sub showversion() {
    print "$copyright\n";
    print <<"DATAEND"
This program is free software that is distributed under the GNU General
Public License, version 2 or later.  See /usr/share/common-licenses/GPL
for more information.
DATAEND
	;
    exit(0);
}


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

sub showcmdlerr(@) {
    map { warn "$_\n" } @_;
    die "Try `$O --help' for more information.\n";
}


__END__


#########################################################################
# Program documentation in POD format

=head1 NAME

adduser.local - adduser(8) local system additions

=head1 SYNOPSIS

/usr/local/sbin/adduser.local [B<--dry-run>] [B<--conf> FILE] [B<--quiet>]
[B<--verbose>] [B<--help>] [B<--version>] USERNAME [UID GID HOMEDIR]

=head1 DESCRIPTION

The B<adduser.local> script, once installed as
F</usr/local/sbin/adduser.local>, is automatically called by the
adduser(8) system program on a Debian system.  This script completes the
creation of a user account by parsing a system-dependent configuration
file, F</etc/adduser.local.conf>.  That configuration file lists a number
of "services" to be configured, where each service is simply a convenient
name for directories that must be created, Unix groups to which the user
must be added, files that need to be copied, symbolic links to be created
and so on.

This script is automatically called by adduser(8) with arguments
I<USERNAME UID GID HOMEDIR>.  In addition, this script may be called
manually.  In this case, only I<USERNAME> needs to be passed, along with
options as described later in B<OPTIONS>.

Note that adduser(8) can now perform I<some> of the tasks that
B<adduser.local> does, particularly by using the EXTRA_GROUPS and
ADD_EXTRA_GROUPS variables in F</etc/adduser.conf>.  However,
B<adduser.local> is far more flexible than doing just that...

=head1 OPTIONS

=over 4

=item B<-n>, B<--dry-run>

Pretend to fulfil everything required, without actually doing anything.

=item B<-c>, B<--conf> I<FILE>

Use configuration file I<FILE> instead of the default
F</etc/adduser.local.conf>.

=item B<-q>, B<--quiet>

Don't show extraneous output.

=item B<-v>, B<--verbose>

Show output about what was done (default).

=item B<-h>, B<--help>

Show a brief command-line summary.

=item B<-V>, B<--version>

Show the version of the B<adduser.local> script.

=back

=head1 RETURN VALUE

B<adduser.local> returns a successful (zero) exit status if no severe
errors were detected, otherwise a non-zero exit code is returned.

=head1 EXAMPLES

To add the user "john" to your system:

    adduser john

This automatically calls B<adduser.local> with the appropriate arguments.

If you would like to rerun the B<adduser.local> script (such as after
modifying its configuration file) for the user "john":

    adduser.local john

=head1 FILES

=over 4

=item F</etc/adduser.local.conf>

Configuration for B<adduser.local>.  The default configuration is
extensively documented.

=back

=head1 FEEDBACK

Your comments, suggestions, corrections and enhancements are always warmly
welcomed!  Please send these to:

    Postal:   John Zaitseff,
              The ZAP Group,
              Unit 6, 116 Woodburn Road,
              Berala, NSW, 2141,
              Australia

    E-mail:   J.Zaitseff@zap.org.au
    Web:      http://www.zap.org.au/software/utils/adduser.local/
    FTP:      ftp://ftp.zap.org.au/pub/utils/adduser.local/adduser.local.tar.gz

=head1 COPYRIGHT

Copyright (C) 1999-2013, John Zaitseff.

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 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

=head1 SEE ALSO

adduser(8)

=cut