#!/usr/bin/perl -w
#
# smbconfig  by Guillaume Cottenceau <gc@mandrakesoft.com>
#
# Copyright (c) 2000 by Mandrakesoft
#
# Permission to use, copy, modify, and distribute this software and its
# documentation under the terms of the GNU General Public License is hereby 
# granted. No representations are made about the suitability of this software 
# for any purpose. It is provided "as is" without express or implied warranty.
# See the GNU General Public License for more details.

$program_name = "smbconfig";
$version = "0.1.3";

$debug_printings = 0;


sub debug_print
{
    $debug_printings && print "[DEBUG] ".$_[0];
}

sub debug_print2
{
    $debug_printings && print $_[0];
}


sub fail
{
    die "Exiting on failure.\n";
}


sub fail_with_message
{
    print $_[0];
    fail();
}


@options = ( [ "--debug", "\t\tadditional debug printings", \$debug_printings ] );

@modes = ( [ "--help", "\t\tthis help screen", \&show_options ],
	   [ "--set-security-share", "setup security = share, very useful because we would need otherwise smbpasswd", \&set_security_share ],
	   [ "--set-hosts-allow=<..>", "setup which hosts are allowed to access; for example \"192.168.1. 127.\"", \&set_hosts_allow ],
	   [ "--set-workgroup=<name>", "setup workgroup name", \&set_workgroup ],
	   [ "--set-banner=<name>", "setup the \"server string\" banner of this smb server", \&set_banner ],
	   [ "--remove-homes", "\tremove the default [homes] share (which needs the security=user)", \&remove_homes ],
	   [ "--enable-public", "\tenable read-write share \"public\" at /home/local/samba-public", \&enable_corpo_public ],
	   [ "--enable-printer-access", "setup access to printers of this machine", \&set_printer_access ] );



sub read_conf
{
    open(FH, "+< /etc/samba/smb.conf") or fail_with_message("Could not open /etc/samba/smb.conf\n");
    @conf = <FH> or fail_with_message("Could not read /etc/samba/smb.conf\n");
    debug_print("/etc/samba/smb.conf read, #lines=".$#conf."\n");
}

sub write_conf
{
    debug_print("Will write /etc/samba/smb.conf, #lines=".$#conf."\n");
    seek(FH, 0, 0) or fail_with_message("Could not seek in /etc/samba/smb.conf\n");
    print FH @conf or fail_with_message("Could not write /etc/samba/smb.conf\n");
    truncate(FH, tell(FH)) or fail_with_message("Could not truncate /etc/samba/smb.conf\n");
    close(FH) or fail_with_message("Could not close /etc/samba/smb.conf\n");
}

# set_parameter: section param value
sub set_parameter
{
    my $section = $_[0]; my $param = $_[1]; my $value = $_[2];
    debug_print("Attempt to find section \"$section\", parameter \"$param\", and setup to \"$value\"\n");
    my $i = 0;
    ($i++ && (lc($_) =~ /^\s*\[$section\]/) && last) foreach (@conf);
    while (1)
    {
	($i < $#conf) or ($conf[$i] = "$conf[$i]\n\n\t$param = $value") and last;
	($conf[$i] =~ /^\s*\[\S+\]/) && ($conf[$i] = "\t$param = $value\n\n$conf[$i]") && last;
	($conf[$i] =~ /^\s*$param\s*=/) && ($conf[$i] = "\t$param = $value\n") && last;
	$i++;
    }
}

sub enable_corpo_public
{
    system("mkdir -p /home/local/samba-public") && fail_with_message("Could not create public dir. Probably run as non-root..\n");
    system("chown nobody /home/local/samba-public") && fail_with_message("Could not chown public dir to nobody. Requests admin help.\n");
    my $i = 0;
    ($i++ && (lc($_) =~ /^\s*\[public\]/) && fail_with_message("An active [public] section has been found in /etc/samba/smb.conf at line $i\n")) foreach (@conf);
    push(@conf, ( "$banner"."[public]\n\tcomment = Public space with read-write access\n\tpath = /home/local/samba-public\n\tguest ok = yes\n\twriteable = yes\n" ));
    $did_something = 1;
}


sub set_workgroup
{
    set_parameter("global", "workgroup", $_[0]);
    $did_something = 1;
}

sub set_banner
{
    set_parameter("global", "server string", $_[0]);
    $did_something = 1;
}

sub set_security_share
{
    set_parameter("global", "security", "share");
    $did_something = 1;
}

sub set_hosts_allow
{
    set_parameter("global", "hosts allow", $_[0]);
    $did_something = 1;
}


sub set_printer_access
{
    my $i = 0; my $found = 0;
    # look for default section "printers"
    ($i++ && (lc($_) =~ /^\s*\[printers\]/) && ($found = 1) && last) foreach (@conf);
    ($found) && debug_print("Printer section found at line $i\n");
    if ($found == 1)
    {
	$conf[$i-1] = ";".$conf[$i-1];
	while ($i <= $#conf)
	{
	    (($conf[$i] =~ /^\s*\[\S+\]/) && last) || ($conf[$i] = ";".$conf[$i]);
	    $i++;
	}    
	debug_print("End of printer section at line $i\n");
    }
    push(@conf, ( "$banner"."[printers]\n\tcomment = All Printers\n\tpath = /var/spool/samba\n\tbrowseable = no\n\tguest ok = yes\n\twritable = no\n\tprintable = yes\n" ));
    $did_something = 1;
}

sub remove_homes
{
    my $i = 0; my $found = 0;
    # look for default section "printers"
    ($i++ && (lc($_) =~ /^\s*\[homes\]/) && ($found = 1) && last) foreach (@conf);
    ($found) && debug_print("[homes] section found at line $i\n");
    if ($found == 1)
    {
	$conf[$i-1] = ";".$conf[$i-1];
	while ($i <= $#conf)
	{
	    (($conf[$i] =~ /^\s*\[\S+\]/) && last) || ($conf[$i] = ";".$conf[$i]);
	    $i++;
	}    
	debug_print("End of [homes] section at line $i\n");
    }
    $did_something = 1;
}


sub show_options
{
    print "$program_name v$version helps auto-config of Samba.\n\n";

    print "mode:\n";
    print "\t".$_->[0]."\t\t".$_->[1]."\n" foreach (@modes);
    print "options:\n";
    print "\t".$_->[0]."\t\t".$_->[1]."\n" foreach (@options);
    print "\n";
    $did_something = 1;
}


sub arg_without_value
{
    $_[0] =~ /([^=]*)/;
    return $1;
}

sub arg_value
{
    $_[0] =~ /([^=]*)=(.*)/;
    return $2;
}

# Disable file buffering [to display strings on the tty even when no trailing \n is added]
$| = 1;

$date = `date`; chop $date;
$host = `hostname`; chop $host;
$banner = "\n### Autogenerated by $program_name at $date on host $host\n";

$did_something = 0;


foreach $arg (@ARGV)
{
    (($arg eq $_->[0]) && (${$_->[2]} = 1)) foreach (@options)
}


read_conf();

foreach $arg (@ARGV)
{
    ((arg_without_value($arg) eq arg_without_value($_->[0])) && &{$_->[2]}(arg_value($arg))) foreach (@modes)
}


($did_something && write_conf()) || show_options();



# Changelog
#
# 0.1.3
#      remove smb.conf end of file bug
#
# 0.1.2
#      added parameter support: hosts allow
#
# 0.1.1
#      added parameter support: server string
#      support multiple parameter sets at same time
#      added parameter support: security = share
#      added remove homes
#
# 0.1.0
#      first version with configure for printers, public, workgroup