#!/usr/bin/perl
#============================================================================#
# List all block devices that not exists in fstab                            #
#============================================================================#
# (C) Denis Smirnov <mithraen@freesource.info>                               #
#============================================================================#
use strict;
use warnings qw(FATAL all);
use Cwd 'abs_path';
use Text::Table;

my %devices;

# List all USB devices
foreach ( glob("/dev/disk/by-id/usb-*") ) {
    $devices{ abs_path($_) } = 1;
}

# List all removable devices
{
    my @devs = split( "\n", `/bin/lsblk -d -r -o RM,KNAME` );
    foreach (@devs) {
        next unless /^1\s+(.+)$/;
        $devices{'/dev/'.$1} = 1;
    }
}

# List all devices in /etc/pmount.allow
if ( open my $fh, "<", "/etc/pmount.allow" ) {
    while (<$fh>) {
        s/#.*//;
        s/\s+$//;
        next if $_ eq '';
        $_ = abs_path($_) if -l $_;
        $devices{$_} = 1;
    }
    close $fh;
}

# Parse /etc/fstab
my %disks;
my %fstab_dev;
my %fstab_uuid;
my %fstab_label;

sub parse_fstab($) {
    open( my $fh, "<", $_[0] ) || return;
    my @out;
    while (<$fh>) {
        my %h;
        s/#.*//;
        s/\s+$//;
        next if $_ eq '';

        my ( $dev, $uuid, $label ) = ( '', '', '' );
        if (s/^UUID=([^\s"]+)\s+//) {
            $uuid = $1;
            $h{uuid} = $1;
        }
        elsif (s/^UUID="([^"]+)"\s+//) {
            $uuid = $1;
            $h{uuid} = $1;
        }
        elsif (s/^LABEL=([^\s"]+)\s+//) {
            $label = $1;
            $h{label} = $1;
        }
        elsif (s/^LABEL="((?:[^"]|"")+)"\s+//) {
            $label = $1;
            $label =~ s/""/"/g;
            $h{label} = $1;
        }
        elsif (s/^([^\s"]+)\s+//) {
            $dev = $1;
            $h{dev} = $1;
        }
        else {
            next;
        }
        my @fields = split( /\s+/, $_ );
        $h{mountpoint} = shift(@fields);
        $h{fs}         = shift(@fields);
        my @opts = split( ',', shift(@fields) );
        foreach my $opt (@opts) {
            $h{opts}->{$opt} = 1;
        }

        push @out, \%h;
    }
    close $fh;
    return @out;
}

sub parse_line($) {
    my $fields = $_[0];
    my %h;
    while ( $fields =~ s/^\s*([^"]+)="([^\"]*)"\s*// ) {
        $h{$1} = $2;
    }
    my $dev = $h{KNAME};
    if ( $h{TYPE} eq 'disk' ) {
        $disks{$dev} = \%h;
    }
    if ( $h{TYPE} eq 'part' ) {
        my $basedev = $dev;
        $basedev =~ s/\d+$//;
        foreach my $key ( keys %h ) {
            if ( $h{$key} eq '' ) {
                $h{$key} = $disks{$basedev}->{$key};
            }
        }
    }

   return if $h{FSTYPE} eq '';
    return if $h{FSTYPE} eq 'swap';
    return if $h{FSTYPE} eq 'linux_raid_member';
    return if $h{FSTYPE} eq 'LVM2_member';

    # skip LVM partitions
    #    return if $h{TYPE} eq 'lvm';

    # skip FS in fstab
    return if defined $fstab_label{ $h{LABEL} };
    return if defined $fstab_uuid{ $h{UUID} };
    return if defined $fstab_dev{ "/dev/" . $h{KNAME} };

    return \%h;
}

foreach ( parse_fstab "/etc/fstab" ) {
    if ( defined $_->{opts}->{user} ) {
        if ( defined $_->{dev} ) {
            my $dev = $_->{dev};
            $dev = abs_path($dev) if -l $dev;
            $devices{$dev} = 1;
        }
        next;
    }

    if ( defined $_->{dev} ) {
        my $dev = $_->{dev};
        $dev = abs_path($dev) if -l $dev;
        $fstab_dev{$dev} = 1;
    }
    $fstab_label{ $_->{label} } = 1 if defined $_->{label};
    $fstab_uuid{ $_->{uuid} }   = 1 if defined $_->{uuid};
}

my @out;

# Get all info about removable and USB devices
open( my $fh, "-|", '/bin/lsblk', '-o',
    'NAME,FSTYPE,LABEL,MOUNTPOINT,SIZE,RM,KNAME,MODEL,TYPE,UUID', '-P' );

my $tb =
  Text::Table->new( 'NAME', 'MOUNTPOINT', 'LABEL', 'FSTYPE', "SIZE\n&left",
    'MODEL' );

while (<$fh>) {
    my $h = parse_line($_);
    next unless defined $h;
    next unless defined $devices{ "/dev/" . $h->{KNAME} };
    $tb->add(
        $h->{NAME},   $h->{MOUNTPOINT}, $h->{LABEL},
        $h->{FSTYPE}, $h->{SIZE},       $h->{MODEL}
    );

    my $dev = "/dev/" . $h->{KNAME};
    push @out, $dev;
}

print $tb;