backup/snap-common

   1 # sourced by snap/lvm and snap/remountrocp
   2
   3 #---------- common arg parsing
   4
   5 nargs=$#
   6 opmode="$1"
   7 vardir="$2"
   8 device="$3"
   9 mountpoint="$4"
  10
  11 lvm_lv=chiark-backup
  12 lvm_lvtools_opts='-A n'
  13 lvm_lvcreate_opts=
  14 lvm_lvcreate_args=
  15
  16 test ! -f /etc/chiark-backup/settings.sh || . /etc/chiark-backup/settings.sh
  17
  18 case "$nargs.$opmode" in
  19 4.snap|2.drop)
  20         ;;
  21 *)
  22         cat >&2 <<END
  23 usage: .../$snapkind snap VARDIR DEV MOUNT
  24        .../$snapkind drop VARDIR
  25 END
  26         exit 1
  27         ;;
  28 esac
  29
  30 #---------- common functions
  31
  32 lvmunmapperdevice () {
  33         # turns device=/dev/mapper/... into /dev/<group>/<volume>
  34         case "$device" in
  35         /dev/mapper/*)
  36                 device="`printf '%s' "$device" | perl -pe '
  37                         s,^/dev/mapper/,,;
  38                         die if m,/,;
  39                         s,\-\-,!,g;
  40                         s,\-,/,g;
  41                         s,\!,-,g;
  42                         s,^,/dev/,;
  43                 '`"
  44                 ;;
  45         esac
  46 }
  47
  48 lvmdevice2vgroup () {
  49         vgroup="${device#/dev/}"
  50         vgroup="${vgroup%/*}"
  51 }
  52
  53 lvmdropcore () {
  54         snmnt="$vardir/snap-mount"
  55         umount -v "$snmnt" || true
  56         test ! -d "$snmnt" || rmdir -- "$snmnt"
  57
  58         set +e
  59         old_lv_dev="$(readlink $vardir/snap-device)"
  60         rc=$?
  61         set -e
  62
  63         if [ $rc = 0 ]; then
  64                 set +e
  65                 lvchange    $lvm_lvtools_opts -a n $old_lv_dev
  66                 lvremove -f $lvm_lvtools_opts      $old_lv_dev
  67                 set -e
  68                 rm $vardir/snap-device
  69         fi
  70 }
  71
  72 lvmextentscore1 () {
  73         # vgroup must be set
  74         vgdisplay_out="$(really vgdisplay -c "$vgroup")"
  75         extents="$(printf "%s" "$vgdisplay_out" | awk -F: '{print $16}')"
  76         extsize="$(printf "%s" "$vgdisplay_out" | awk -F: '{print $13}')"
  77 }
  78
  79 lvmextentscore2 () {
  80         if [ $extents2 -lt $extents ]; then extents=$extents2; fi
  81         lvm_lvsize_opts="-l $extents"
  82 }
  83
  84 lvmcreatecore1 () {
  85         # vgroup must be set
  86         lvpath="/dev/$vgroup/$lvm_lv"
  87         ln -s -- "$lvpath" "$vardir"/snap-device
  88         sync
  89 }