#!/usr/bin/perl -w
# virt-ls
# Copyright (C) 2009 Red Hat Inc.
#
# 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., 675 Mass Ave, Cambridge, MA 02139, USA.

use warnings;
use strict;

use Sys::Guestfs;
use Sys::Guestfs::Lib qw(open_guest get_partitions resolve_windows_path
  inspect_all_partitions inspect_partition
  inspect_operating_systems mount_operating_system);
use Pod::Usage;
use Getopt::Long;
use Locale::TextDomain 'libguestfs';
use File::Temp qw/tempdir/;

=encoding utf8

=head1 NAME

virt-ls - List files in a virtual machine

=head1 SYNOPSIS

 virt-ls [--options] domname directory

 virt-ls [--options] disk.img [disk.img ...] directory

=head1 DESCRIPTION

C<virt-ls> is a command line tool to list the names of files in a
directory inside a virtual machine or disk image.

C<virt-ls> is just a simple wrapper around L<libguestfs(3)>
functionality.  For more complex cases you should look at the
L<guestfish(1)> tool.

C<virt-ls> can be used in one of three modes: simple, long and
recursive.  A simple listing is like the ordinary L<ls(1)> command:

 $ virt-ls myguest /
 bin
 boot
 [etc.]

With the C<-l> (C<--long>) option, C<virt-ls> shows more detail:

 $ virt-ls -l myguest /
 total 204
 dr-xr-xr-x.   2 root root   4096 2009-08-25 19:06 bin
 dr-xr-xr-x.   5 root root   3072 2009-08-25 19:06 boot
 [etc.]

With the C<-R> (C<--recursive>) option, C<virt-ls> lists the
names of files and directories recursively:

 $ virt-ls -R myguest /tmp
 foo
 foo/bar
 [etc.]

You I<cannot> combine these options.  To do more complicated things,
use L<guestfish(1)>.

=head1 OPTIONS

=over 4

=cut

my $help;

=item B<--help>

Display brief help.

=cut

my $version;

=item B<--version>

Display version number and exit.

=cut

my $uri;

=item B<--connect URI> | B<-c URI>

If using libvirt, connect to the given I<URI>.  If omitted, then we
connect to the default libvirt hypervisor.

If you specify guest block devices directly, then libvirt is not used
at all.

=cut

my $mode;

=item B<-l> | B<--long>

=item B<-R> | B<--recursive>

Select the mode.  With neither of these options, C<virt-ls>
produces a simple, flat list of the files in the named directory.

C<virt-ls -l> produces a "long listing", which shows more detail (just
like the plain C<ls -l> command).

C<virt-ls -R> produces a recursive list of files starting at the named
directory.  See the documentation for the C<guestfs_find> command
L<guestfs(3)> for precise details.

You cannot combine these options.

=back

=cut

sub set_mode_l
{
    die __"virt-ls: cannot combine -l and -R options\n" if $mode;
    $mode = "l";
}

sub set_mode_R
{
    die __"virt-ls: cannot combine -l and -R options\n" if $mode;
    $mode = "R";
}

GetOptions ("help|?" => \$help,
            "version" => \$version,
            "connect|c=s" => \$uri,
            "long|l" => \&set_mode_l,
            "recursive|R" => \&set_mode_R,
    ) or pod2usage (2);
pod2usage (1) if $help;
if ($version) {
    my $g = Sys::Guestfs->new ();
    my %h = $g->version ();
    print "$h{major}.$h{minor}.$h{release}$h{extra}\n";
    exit
}

pod2usage (__"virt-ls: no image, VM names or directory to list given")
    if @ARGV <= 1;

my $directory = pop @ARGV;

my $g;
if ($uri) {
    $g = open_guest (\@ARGV, address => $uri);
} else {
    $g = open_guest (\@ARGV);
}

$g->launch ();

# List of possible filesystems.
my @partitions = get_partitions ($g);

# Now query each one to build up a picture of what's in it.
my %fses =
    inspect_all_partitions ($g, \@partitions,
      use_windows_registry => 0);

my $oses = inspect_operating_systems ($g, \%fses);

my @roots = keys %$oses;
die __"multiboot operating systems are not supported by virt-ls\n" if @roots > 1;
my $root_dev = $roots[0];

my $os = $oses->{$root_dev};
mount_operating_system ($g, $os);

unless ($mode) {
    my @r = $g->ls ($directory);
    print "$_\n" foreach @r;
} elsif ($mode eq "l") {
    print ($g->ll ($directory));
} else { # $mode eq "R"
    my $dir = tempdir (CLEANUP => 1);
    $g->find0 ($directory, "$dir/find0");
    open F, "$dir/find0" or die "$dir/find0: $!\n";
    my $r;
    my $line;
    while (($r = read (F, $line, 1024)) > 0) {
        $line =~ tr{\0}{\n};
        print $line;
    }
    close F;
}

=head1 SHELL QUOTING

Libvirt guest names can contain arbitrary characters, some of which
have meaning to the shell such as C<#> and space.  You may need to
quote or escape these characters on the command line.  See the shell
manual page L<sh(1)> for details.

=head1 SEE ALSO

L<guestfs(3)>,
L<guestfish(1)>,
L<virt-cat(1)>,
L<virt-tar(1)>,
L<Sys::Guestfs(3)>,
L<Sys::Guestfs::Lib(3)>,
L<Sys::Virt(3)>,
L<http://libguestfs.org/>.

=head1 AUTHOR

Richard W.M. Jones L<http://people.redhat.com/~rjones/>

=head1 COPYRIGHT

Copyright (C) 2009 Red Hat Inc.

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., 675 Mass Ave, Cambridge, MA 02139, USA.