Resetting Directory and File Masks on Synology NAS

#!/usr/bin/perl
#
# Modify the smb.conf file on the Synology disk station
#

# Location of the smb.conf and temp files
$smb_file = "/usr/syno/etc/smb.conf";
$tmp_file = "/tmp/mod_smb_cfg.$$";

# Below are the names of the shares and to the right
# are the config lines to introduce
%share_config =
(
    'archive'            => [
                                  "directory mask = 0755",
                                  "create mask = 0644"
                            ],
    'music'              => [
                                  "directory mask = 0755",
                                  "create mask = 0644"
                            ],
    'pictures'           => [
                                  "directory mask = 0755",
                                  "create mask = 0644"
                            ],
    'public'             => [
                                  "directory mask = 0775",
                                  "create mask = 0664"
                            ]
);

#
# SameOption
#
# This function will check to see if the option names are the same
#
sub SameOption
{
    my (@options) = @_;

    my ($i);

    if ($#options != 1)
    {
        return 0;
    }

    # Normalize values
    for ($i=0; $i<=1; $i++)
    {
        $options[$i] =~ s/=.*//;          # Remove everything after =
        $options[$i] =~ s/^\s+//;         # Remove all leading whitespace
        $options[$i] =~ s/\s$//;          # Remove all trailing whitespace
        1 while $options[$i] =~ s/  / /g; # Remove excess spaces
    }

    if (($options[0] eq $options[1]) && (length($options[0]) > 0))
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

#
# MAIN
#
# The following is the main logic of the program
#

# Read the old config, make changes, writing to a temp file
open(SMBFILE, "< $smb_file") || exit;
open(TMPFILE, "> $tmp_file") || exit;

while(<SMBFILE>)
{
    # We will assume the current line will be printed
    $print_line = 1;

    # This logic will remove lines from the existing config that are
    # added via the $share_config array
    if ((!/^\[/) && (length($section_name) > 0))
    {
        $tline = $_;
        chomp($tline);

        foreach $line ( @{ $share_config{"$section_name"} } )
        {
            # Is the current config option in our
            if (SameOption($tline, $line))
            {
                $print_line = 0;
                last;
            }
        }
    }
    if ($print_line)
    {
        print TMPFILE;
    }
    next unless /^\[/;

    # Add configuration lines as specified in "share_config"
    chomp($section_name = $_);
    $section_name =~ s/^\[//;
    $section_name =~ s/\].*//;
    foreach $line ( @{ $share_config{"$section_name"} } )
    {
        print TMPFILE "\t$line\n";
    }
}

close(SMBFILE);
close(TMPFILE);

# Read the temp file in and replace the original config file
open(TMPFILE, "< $tmp_file") || exit;
open(SMBFILE, "> $smb_file") || exit;

while(<TMPFILE>)
{
    print SMBFILE;
}

close(TMPFILE);
close(SMBFILE);

# Get rid of the temp file
unlink($tmp_file);

#!/bin/sh

if [ $# -eq 0 ]; then
        action=status
else
        action=$1
fi

# dispatch actions
case $action in
        start)
                /usr/local/bin/modify_samba_config
                ;;
        *)
                # Do nothing with any other command
                ;;
esac