blob: 178fd644d2747d43397c3d4e3c100271e82b925a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
#!/bin/sh
layer_dir=/home/d/sami
seed_file=debian-live-8.4.0-amd64-standard.btrfs
layer_file=debian-live-8.4.0-amd64-standard.layer.$$.btrfs
layer_size=1000
mountpoint=layer_dest.$$
disable_stdout() { exec 3>&1; exec >&2; }
enable_stdout() { exec >&3; }
with_stdout() { enable_stdout; "$@"; disable_stdout; }
create_layer_filesystem()
{
[ ! -e "$layer_file" ] || return
mkdir -p "$mountpoint" &&
dd if=/dev/zero of="$layer_file" bs=1M count="$layer_size" &&
mount -o subvol=/,compress "$seed_file" "$mountpoint" &&
layer_dev=$(losetup -f --show "$layer_file") &&
btrfs device add "$layer_dev" "$mountpoint" &&
mount -o rw,remount "$mountpoint"
}
finish()
{
umount "$mountpoint" &&
btrfstune -S1 "$layer_file"
}
set -ex
cd "$layer_dir" &&
disable_stdout &&
create_layer_filesystem &&
with_stdout btrfs receive "$mountpoint" &&
finish
|
