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add --format option and ext2 image output

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This commit is contained in:
Johannes 'josch' Schauer 2020-04-09 18:33:05 +02:00
parent 89e8f7a39a
commit 895c388ede
Signed by: josch
GPG key ID: F2CBA5C78FBD83E1
3 changed files with 339 additions and 80 deletions
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74
coverage.sh
View file

@ -72,7 +72,7 @@ if [ ! -e shared/taridshift ] || [ taridshift -nt shared/taridshift ]; then
fi
starttime=
total=141
total=146
skipped=0
runtests=0
i=1
@ -711,6 +711,31 @@ else
runtests=$((runtests+1))
fi
print_header "mode=$defaultmode,variant=apt: directory ending in .tar"
cat << END > shared/test.sh
#!/bin/sh
set -eu
export LC_ALL=C.UTF-8
$CMD --mode=$defaultmode --variant=apt --format=directory $DEFAULT_DIST /tmp/debian-chroot.tar $mirror
ftype=\$(stat -c %F /tmp/debian-chroot.tar)
if [ "\$ftype" != directory ]; then
echo "expected directory but got: \$ftype" >&2
exit 1
fi
tar -C /tmp/debian-chroot.tar --one-file-system -c . | tar -t | sort | diff -u tar1.txt -
rm -r /tmp/debian-chroot.tar
END
if [ "$HAVE_QEMU" = "yes" ]; then
./run_qemu.sh
runtests=$((runtests+1))
elif [ "$defaultmode" = "root" ]; then
./run_null.sh SUDO
runtests=$((runtests+1))
else
./run_null.sh
runtests=$((runtests+1))
fi
print_header "mode=$defaultmode,variant=apt: test squashfs image"
cat << END > shared/test.sh
#!/bin/sh
@ -737,6 +762,50 @@ else
runtests=$((runtests+1))
fi
for mode in root unshare fakechroot proot; do
print_header "mode=$mode,variant=apt: test ext2 image"
cat << END > shared/test.sh
#!/bin/sh
set -eu
export LC_ALL=C.UTF-8
if [ "\$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
if [ ! -e /mmdebstrap-testenv ]; then
echo "this test modifies the system and should only be run inside a container" >&2
exit 1
fi
adduser --gecos user --disabled-password user
fi
if [ "$mode" = unshare ]; then
if [ ! -e /mmdebstrap-testenv ]; then
echo "this test modifies the system and should only be run inside a container" >&2
exit 1
fi
sysctl -w kernel.unprivileged_userns_clone=1
fi
prefix=
[ "\$(id -u)" -eq 0 ] && [ "$mode" != "root" ] && prefix="runuser -u user --"
[ "$mode" = "fakechroot" ] && prefix="\$prefix fakechroot fakeroot"
\$prefix $CMD --mode=$mode --variant=apt $DEFAULT_DIST /tmp/debian-chroot.ext2 $mirror
mount /tmp/debian-chroot.ext2 /mnt
rmdir /mnt/lost+found
# in fakechroot mode, we use a fake ldconfig, so we have to
# artificially add some files
{ tar -C /mnt -c . | tar -t;
[ "$mode" = "fakechroot" ] && printf "./etc/ld.so.cache\n./var/cache/ldconfig/\n";
[ "$mode" = "fakechroot" ] && printf "./etc/.pwd.lock\n";
} | sort | diff -u tar1.txt -
umount /mnt
rm /tmp/debian-chroot.ext2
END
if [ "$HAVE_QEMU" = "yes" ]; then
./run_qemu.sh
runtests=$((runtests+1))
else
echo "HAVE_QEMU != yes -- Skipping test..." >&2
skipped=$((skipped+1))
fi
done
print_header "mode=auto,variant=apt: test auto-mode without unshare capabilities"
cat << END > shared/test.sh
#!/bin/sh
@ -2017,8 +2086,9 @@ set -eu
export LC_ALL=C.UTF-8
$CMD --mode=root --variant=apt --logfile=log $DEFAULT_DIST /tmp/debian-chroot $mirror
# we check the full log to also prevent debug printfs to accidentally make it into a commit
cat << LOG | diff - log
cat << LOG | diff -u - log
I: chroot architecture $HOSTARCH is equal to the host's architecture
I: automatically chosen format: directory
I: running apt-get update...
I: downloading packages with apt...
I: extracting archives...

2
make_mirror.sh
View file

@ -424,7 +424,7 @@ if [ "$HAVE_QEMU" = "yes" ]; then
tmpdir="$(mktemp -d)"
trap "cleanuptmpdir; cleanup_newcachedir" EXIT INT TERM
pkgs=perl-doc,systemd-sysv,perl,arch-test,fakechroot,fakeroot,mount,uidmap,qemu-user-static,binfmt-support,qemu-user,dpkg-dev,mini-httpd,libdevel-cover-perl,debootstrap,procps,apt-cudf,aspcud,squashfs-tools-ng,python3,libcap2-bin,gpg
pkgs=perl-doc,systemd-sysv,perl,arch-test,fakechroot,fakeroot,mount,uidmap,qemu-user-static,binfmt-support,qemu-user,dpkg-dev,mini-httpd,libdevel-cover-perl,debootstrap,procps,apt-cudf,aspcud,squashfs-tools-ng,genext2fs,python3,libcap2-bin,gpg
if [ "$HAVE_PROOT" = "yes" ]; then
pkgs="$pkgs,proot"
fi

343
mmdebstrap
View file

@ -2771,6 +2771,27 @@ sub guess_sources_format {
return;
}
sub approx_disk_usage {
my $directory = shift;
info "approximating disk usage...";
open my $fh, '-|', 'du', '--block-size', '1024',
'--summarize', '--one-file-system',
$directory // error "failed to fork(): $!";
chomp(
my $du = do { local $/; <$fh> }
);
close $fh;
if (($? != 0) or (!$du)) {
error "du failed: $?";
}
if ($du =~ /^(\d+)\t/) {
return int($1 * 1.1);
} else {
error "unexpected du output: $du";
}
return;
}
sub main() {
umask 022;
@ -2840,6 +2861,7 @@ sub main() {
dryrun => 0,
};
my $logfile = undef;
my $format = 'auto';
Getopt::Long::Configure('default', 'bundling', 'auto_abbrev',
'ignore_case_always');
GetOptions(
@ -2878,6 +2900,7 @@ sub main() {
'q|quiet' => sub { $verbosity_level = 0; },
'v|verbose' => sub { $verbosity_level = 2; },
'd|debug' => sub { $verbosity_level = 3; },
'format=s' => \$format,
'logfile=s' => \$logfile,
# no-op options so that mmdebstrap can be used with
# sbuild-createchroot --debootstrap=mmdebstrap
@ -2955,6 +2978,19 @@ sub main() {
error "invalid mode. Choose from " . (join ', ', @valid_modes);
}
# sqfs is an alias for squashfs
if ($format eq 'sqfs') {
$format = 'squasfs';
}
# dir is an alias for directory
if ($format eq 'dir') {
$format = 'directory';
}
my @valid_formats = ('auto', 'directory', 'tar', 'squashfs', 'ext2');
if (none { $_ eq $format } @valid_formats) {
error "invalid format. Choose from " . (join ', ', @valid_formats);
}
my $check_fakechroot_running = sub {
# test if we are inside fakechroot already
# We fork a child process because setting FAKECHROOT_DETECT seems to
@ -3658,62 +3694,88 @@ sub main() {
my $tar_compressor = get_tar_compressor($options->{target});
# figure out whether a tarball has to be created in the end
$options->{maketar} = 0;
$options->{makesqfs} = 0;
if (
defined $tar_compressor
or $options->{target} =~ /\.tar$/
or $options->{target} eq '-'
or -p $options->{target} # named pipe (fifo)
or -c $options->{target} # character special like /dev/null
) {
$options->{maketar} = 1;
# check if the compressor is installed
if (defined $tar_compressor) {
# figure out the right format
if ($format eq 'auto') {
if ($options->{target} ne '-' and -d $options->{target}) {
$format = 'directory';
} elsif (
defined $tar_compressor
or $options->{target} =~ /\.tar$/
or $options->{target} eq '-'
or -p $options->{target} # named pipe (fifo)
or -c $options->{target} # character special like /dev/null
) {
$format = 'tar';
# check if the compressor is installed
if (defined $tar_compressor) {
my $pid = fork() // error "fork() failed: $!";
if ($pid == 0) {
open(STDOUT, '>', '/dev/null')
or error "cannot open /dev/null for writing: $!";
open(STDIN, '<', '/dev/null')
or error "cannot open /dev/null for reading: $!";
exec { $tar_compressor->[0] } @{$tar_compressor}
or error("cannot exec "
. (join " ", @{$tar_compressor})
. ": $!");
}
waitpid $pid, 0;
if ($? != 0) {
error("failed to start " . (join " ", @{$tar_compressor}));
}
}
} elsif ($options->{target} =~ /\.(squashfs|sqfs)$/) {
$format = 'squashfs';
# check if tar2sqfs is installed
my $pid = fork() // error "fork() failed: $!";
if ($pid == 0) {
open(STDOUT, '>', '/dev/null')
or error "cannot open /dev/null for writing: $!";
open(STDIN, '<', '/dev/null')
or error "cannot open /dev/null for reading: $!";
exec { $tar_compressor->[0] } @{$tar_compressor}
or error(
"cannot exec " . (join " ", @{$tar_compressor}) . ": $!");
exec('tar2sqfs', '--version')
or error("cannot exec tar2sqfs --version: $!");
}
waitpid $pid, 0;
if ($? != 0) {
error("failed to start " . (join " ", @{$tar_compressor}));
error("failed to start tar2sqfs --version");
}
} elsif ($options->{target} =~ /\.ext2$/) {
$format = 'ext2';
# check if the installed version of genext2fs supports tarballs on
# stdin
(undef, my $filename)
= tempfile("mmdebstrap.ext2.XXXXXXXXXXXX", OPEN => 0);
open my $fh, '|-', 'genext2fs', '-B', '1024', '-b', '8', '-N',
'11',
$filename // error "failed to fork(): $!";
# write 10240 null-bytes to genext2fs -- this represents an empty
# tar archive
print $fh ("\0" x 10240)
or error "cannot write to genext2fs process";
close $fh;
my $exitstatus = $?;
unlink $filename // die "cannot unlink $filename";
if ($exitstatus != 0) {
error "genext2fs failed with exit status: $exitstatus";
}
} else {
$format = 'directory';
}
} elsif ($options->{target} =~ /\.(squashfs|sqfs)$/) {
$options->{makesqfs} = 1;
# check if tar2sqfs is installed
my $pid = fork() // error "fork() failed: $!";
if ($pid == 0) {
open(STDOUT, '>', '/dev/null')
or error "cannot open /dev/null for writing: $!";
open(STDIN, '<', '/dev/null')
or error "cannot open /dev/null for reading: $!";
exec('tar2sqfs', '--version')
or error("cannot exec tar2sqfs --version: $!");
}
waitpid $pid, 0;
if ($? != 0) {
error("failed to start tar2sqfs --version");
}
} elsif ($options->{target} =~ /\.ext2$/) {
error "genext2fs does not yet support tarballs as input. See "
. "https://github.com/bestouff/genext2fs/issues/10 for more "
. "information";
info "automatically chosen format: $format";
}
if ($options->{maketar} or $options->{makesqfs}) {
if ($options->{target} eq '-' and $format ne 'tar') {
error "the $format format is unable to write to standard output";
}
if (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
if ( any { $_ eq $options->{variant} } ('extract', 'custom')
and any { $_ eq $options->{mode} } ('fakechroot', 'proot')) {
info "creating a tarball or squashfs image in fakechroot mode or"
. " proot mode might fail in extract and custom variants because"
. " there might be no tar inside the chroot";
info "creating a tarball or squashfs image or ext2 image in"
. " fakechroot mode or proot mode might fail in extract and"
. " custom variants because there might be no tar inside the"
. " chroot";
}
# try to fail early if target tarball or squashfs image cannot be
# opened for writing
@ -3739,7 +3801,7 @@ sub main() {
if (any { $_ eq $options->{mode} } ('unshare', 'root')) {
chmod 0755, $options->{root} or error "cannot chmod root: $!";
}
} else {
} elsif ($format eq 'directory') {
# user does not seem to have specified a tarball as output, thus work
# directly in the supplied directory
$options->{root} = $options->{target};
@ -3789,6 +3851,8 @@ sub main() {
error "cannot create $options->{root}";
}
}
} else {
error "unknown format: $format";
}
# check for double quotes because apt doesn't allow to escape them and
@ -3844,7 +3908,7 @@ sub main() {
my $devtar = '';
# We always craft the /dev entries ourselves if a tarball is to be created
if ($options->{maketar} or $options->{makesqfs}) {
if (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
foreach my $file (@devfiles) {
my ($fname, $mode, $type, $linkname, $devmajor, $devminor)
= @{$file};
@ -3871,8 +3935,13 @@ sub main() {
= sprintf("%06o\0", unpack("%16C*", $entry));
$devtar .= $entry;
}
} elsif ($format eq 'directory') {
# nothing to do
} else {
error "unknown format: $format";
}
my $numblocks = 0;
my $exitstatus = 0;
my @taropts = (
'--sort=name',
@ -3920,12 +3989,24 @@ sub main() {
setup($options);
if (!$options->{dryrun} && $format eq 'ext2') {
my $numblocks = approx_disk_usage($options->{root});
debug "sending nblks";
print $childsock (
pack("n", length "$numblocks") . "nblks$numblocks");
$childsock->flush();
debug "waiting for okthx";
checkokthx $childsock;
}
print $childsock (pack('n', 0) . 'adios');
$childsock->flush();
close $childsock;
if ($options->{maketar} or $options->{makesqfs}) {
if ($options->{dryrun}) {
info "simulate creating tarball...";
} elsif (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
info "creating tarball...";
# redirect tar output to the writing end of the pipe so
@ -3942,6 +4023,10 @@ sub main() {
or error "tar failed: $?";
info "done";
} elsif ($format eq 'directory') {
# nothing to do
} else {
error "unknown format: $format";
}
exit 0;
@ -3969,6 +4054,15 @@ sub main() {
setup($options);
if (!$options->{dryrun} && $format eq 'ext2') {
my $numblocks = approx_disk_usage($options->{root});
print $childsock (
pack("n", length "$numblocks") . "nblks$numblocks");
$childsock->flush();
debug "waiting for okthx";
checkokthx $childsock;
}
print $childsock (pack('n', 0) . 'adios');
$childsock->flush();
@ -3976,7 +4070,7 @@ sub main() {
if ($options->{dryrun}) {
info "simulate creating tarball...";
} elsif ($options->{maketar} or $options->{makesqfs}) {
} elsif (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
info "creating tarball...";
# redirect tar output to the writing end of the pipe so that
@ -4028,6 +4122,10 @@ sub main() {
}
info "done";
} elsif ($format eq 'directory') {
# nothing to do
} else {
error "unknown format: $format";
}
exit 0;
@ -4360,6 +4458,23 @@ sub main() {
if ($? != 0) {
error "tar failed";
}
} elsif ($msg eq "nblks") {
# handle the nblks message
debug "received message: nblks";
{
my $ret = read($parentsock, $numblocks, $len)
// error "cannot read from socket: $!";
if ($ret == 0) {
error "received eof on socket";
}
}
if ($numblocks !~ /^\d+$/) {
error "invalid number of blocks: $numblocks";
}
debug "sending okthx";
print $parentsock (pack("n", 0) . "okthx")
or error "cannot write to socket: $!";
$parentsock->flush();
} else {
error "unknown message: $msg";
}
@ -4381,7 +4496,9 @@ sub main() {
if ($options->{dryrun}) {
# nothing to do
} elsif ($options->{maketar} or $options->{makesqfs}) {
} elsif ($format eq 'directory') {
# nothing to do
} elsif (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
# we use eval() so that error() doesn't take this process down and
# thus leaves the setup() process without a parent
eval {
@ -4390,17 +4507,27 @@ sub main() {
error "cannot copy to standard output: $!";
}
} else {
if ($options->{makesqfs} or defined $tar_compressor) {
if ( $format eq 'squashfs'
or $format eq 'ext2'
or defined $tar_compressor) {
my @argv = ();
if ($options->{makesqfs}) {
if ($format eq 'squashfs') {
push @argv, 'tar2sqfs',
'--quiet', '--no-skip', '--force',
'--exportable',
'--compressor', 'xz',
'--block-size', '1048576',
$options->{target};
} else {
} elsif ($format eq 'ext2') {
if ($numblocks <= 0) {
error "invalid number of blocks: $numblocks";
}
push @argv, 'genext2fs', '-B', 1024, '-b', $numblocks,
'-N', '0', $options->{target};
} elsif ($format eq 'tar') {
push @argv, @{$tar_compressor};
} else {
error "unknown format: $format";
}
POSIX::sigprocmask(SIG_BLOCK, $sigset)
or error "Can't block signals: $!";
@ -4417,13 +4544,16 @@ sub main() {
POSIX::sigprocmask(SIG_UNBLOCK, $sigset)
or error "Can't unblock signals: $!";
if ($options->{makesqfs}) {
# redirect stdout to file or /dev/null
if ($format eq 'squashfs' or $format eq 'ext2') {
open(STDOUT, '>', '/dev/null')
or error "cannot open /dev/null for writing: $!";
} else {
} elsif ($format eq 'tar') {
open(STDOUT, '>', $options->{target})
or error
"cannot open $options->{target} for writing: $!";
} else {
error "unknown format: $format";
}
open(STDIN, '<&', $rfh)
or error "cannot open file handle for reading: $!";
@ -4452,6 +4582,8 @@ sub main() {
warning "creating tarball failed: $@";
$exitstatus = 1;
}
} else {
error "unknown format: $format";
}
close($rfh);
waitpid $pid, 0;
@ -4462,8 +4594,12 @@ sub main() {
# change signal handler message
$waiting_for = "cleanup";
if (($options->{maketar} or $options->{makesqfs})
and -e $options->{root}) {
if ($format eq 'directory') {
# nothing to do
} elsif (any { $_ eq $format } ('tar', 'squashfs', 'ext2')) {
if (!-e $options->{root}) {
error "$options->{root} does not exist";
}
info "removing tempdir $options->{root}...";
if ($options->{mode} eq 'unshare') {
# We don't have permissions to remove the directory outside
@ -4527,6 +4663,8 @@ sub main() {
} else {
error "unknown mode: $options->{mode}";
}
} else {
error "unknown format: $format";
}
if ($got_signal) {
@ -4575,30 +4713,11 @@ installed inside the chroot. If any mirror contains a tor+xxx URI, then the
apt-transport-tor package will be installed inside the chroot.
The optional I<TARGET> argument can either be the path to a directory, the path
to a tarball filename, the path to a squashfs image, a FIFO, a character
special device, or C<->. If I<TARGET> ends with C<.tar>, or with any of the
filename extensions listed in the section B<COMPRESSION>, or if I<TARGET> is a
FIFO or a character special device, then I<TARGET> will be interpreted as a
path to a tarball filename. If I<TARGET> ends with C<.squashfs> or C<.sqfs>,
then I<TARGET> will be interpreted as a path to a squashfs image. If I<TARGET>
is the path to a tarball filename or a squashfs image or if I<TARGET> is C<->
or if no I<TARGET> was specified, B<mmdebstrap> will create a temporary chroot
directory in C<$TMPDIR> or F</tmp>. If I<TARGET> is the path to a tarball
filename, B<mmdebstrap> will create a tarball of that directory and store it as
I<TARGET>, optionally applying a compression algorithm as indicated by its
filename extension. If I<TARGET> is C<-> or if no I<TARGET> was specified, then
an uncompressed tarball of that directory will be sent to standard output. When
B<mmdebstrap> creates a tarball it also stores extended attributes. To preserve
the extended attributes, you have to pass B<--xattrs --xattrs-include='*'> to
tar when extracting the tarball. If I<TARGET> is the path to a squashfs image,
B<mmdebstrap> will create an xz compressed image with a blocksize of 1048576
bytes. If I<TARGET> does neither end with C<.tar> nor with any of the filename
extensions listed in the section B<COMPRESSION>, nor with C<.squashfs> or
C<.sqfs>, then I<TARGET> will be interpreted as the path to a directory. If the
directory already exists, it must either be empty or only contain an empty
C<lost+found> directory. If a directory is chosen as output in any other mode
than B<sudo>, then its contents will have wrong ownership information and
special device files will be missing.
to a tarball filename, the path to a squashfs image, the path to an ext2 image,
a FIFO, a character special device, or C<->. Without the B<--format> option,
I<TARGET> will be used to choose the format. See the section B<FORMATS> for
more information. If no I<TARGET> was specified or if I<TARGET> is C<->, an
uncompressed tarball will be sent to standard output.
The I<SUITE> may be a valid release code name (eg, sid, stretch, jessie) or a
symbolic name (eg, unstable, testing, stable, oldstable). Any suite name that
@ -4651,6 +4770,12 @@ B<auto>, B<sudo>, B<root>, B<unshare>, B<fakeroot>, B<fakechroot>, B<proot> and
B<chrootless>. The default mode is B<auto>. See the section B<MODES> for more
information.
=item B<--format>=I<name>
Choose the output format. Valid format I<name>s are B<auto>, B<directory>,
B<tar>, B<squashfs>, and B<ext2>. The default format is B<auto>. See the
section B<FORMATS> for more information.
=item B<--aptopt>=I<option>|I<file>
Pass arbitrary I<option>s to apt. Will be added to
@ -5006,6 +5131,70 @@ The B<important> set plus all packages with Priority:standard.
=back
=head1 FORMATS
The output format of mmdebstrap is specified using the B<--format> option.
Without that option the default format is I<auto>. The following formats exist:
=over 8
=item B<auto>
When selecting this format (the default), the actual format will be inferred
from the I<TARGET> positional argument. If I<TARGET> is an existing directory,
and does not equal to C<->, then the B<directory> format will be chosen. If
I<TARGET> ends with C<.tar> or with one of the filename extensions listed in
the section B<COMPRESSION>, or if B<TARGET> equals C<->, or if B<TARGET> is a
named pipe (fifo) or if B<TARGET> is a character special file like
F</dev/null>, then the B<tar> format will be chosen. If I<TARGET> ends with
C<.squashfs> or C<.sqfs>, then the B<squashfs> format will be chosen. If
<TARGET> ends with C<.ext2> then the B<ext2> format will be chosen. If none of
these conditions apply, the B<directory> format will be chosen.
=item B<directory>, B<dir>
A chroot directory will be created in I<TARGET>. If the directory already
exists, it must either be empty or only contain an empty C<lost+found>
directory. The special I<TARGET> C<-> does not work with this format because a
directory cannot be written to standard output. If you need your directory be
named C<->, then just explicitly pass the relative path to it like F<./->. If
a directory is chosen as output in any other mode than B<sudo>, then its
contents will have wrong ownership information and special device files will be
missing.
=item B<tar>
A temporary chroot directory will be created in C<$TMPDIR> or F</tmp> if
C<$TMPDIR> is not set. A tarball of that directory will be stored in I<TARGET>
or sent to standard output if I<TARGET> was omitted or if I<TARGET> equals
C<->. If I<TARGET> ends with one of the filename extensions listed in the
section B<COMPRESSION>, then a compressed tarball will be created. The tarball
will be in POSIX 1003.1-2001 (pax) format and will contain extended attributes.
To preserve the extended attributes, you have to pass B<--xattrs
--xattrs-include='*'> to tar when extracting the tarball.
=item B<squashfs>, B<sqfs>
A temporary chroot directory will be created in C<$TMPDIR> or F</tmp> if
C<$TMPDIR> is not set. A tarball of that directory will be piped to the
C<tar2sqfs> utility, which will create an xz compressed squashfs image with a
blocksize of 1048576 bytes in I<TARGET>. The special I<TARGET> C<-> does not
work with this format because C<tar2sqfs> can only write to a regular file. If
you need your squashfs image be named C<->, then just explicitly pass the
relative path to it like F<./->.
=item B<ext2>
A temporary chroot directory will be created in C<$TMPDIR> or F</tmp> if
C<$TMPDIR> is not set. A tarball of that directory will be piped to the
C<genext2fs> utility, which will create an ext2 image that will be
approximately 90% full in I<TARGET>. The special I<TARGET> C<-> does not work
with this format because C<genext2fs> can only write to a regular file. If you
need your ext2 image be named C<->, then just explicitly pass the relative path
to it like F<./->.
=back
=begin comment
=head1 HOOKS