bin/live-snapshot

   1 #!/bin/sh
   2
   3 # live-snapshot - utility to manage Debian Live systems snapshots
   4 #
   5 #   This program mount a device (fallback to /tmpfs under /mnt/snapshot
   6 #   and save the /live/cow (or a different dir) filesystem in it for reusing
   7 #   in another live-initramfs session. Look at manpage for more info.
   8 #
   9 # Copyright (C) 2006 Marco Amadori <marco.amadori@gmail.com>
  10 #
  11 # This program is free software; you can redistribute it and/or modify
  12 # it under the terms of the GNU General Public License as published by
  13 # the Free Software Foundation; either version 2 of the License, or
  14 # (at your option) any later version.
  15 #
  16 # This program is distributed in the hope that it will be useful,
  17 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19 # GNU General Public License for more details.
  20 #
  21 # You should have received a copy of the GNU General Public License
  22 # along with this program; if not, write to the Free Software
  23 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  24 #
  25 # On Debian systems, the complete text of the GNU General Public License
  26 # can be found in /usr/share/common-licenses/GPL-2 file.
  27
  28 PROGRAM="$(basename $0)"
  29 VERSION=0.0.1
  30
  31 # Source live conf
  32 if [ -e /etc/live.conf ]
  33 then
  34         . /etc/live.conf
  35 else
  36         USERNAME=$(cat /etc/passwd | grep "999" | cut -f1 -d ':')
  37         HOSTNAME=$(hostname)
  38 fi
  39
  40 export USERNAME USERFULLNAME HOSTNAME
  41
  42 # Source helper functions
  43 helpers="/usr/share/initramfs-tools/scripts/live-helpers"
  44
  45 if [ -e "${helpers}" ]
  46 then
  47         . "${helpers}"
  48 else
  49         echo "Error: I cannot found helper functions \"${helpers}\"."
  50         exit 1
  51 fi
  52
  53 # Define LSB log_* functions.
  54 # Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
  55 . /lib/lsb/init-functions
  56
  57 MOUNTP=""
  58 COW=""
  59 DEV=""
  60 DEST=""
  61 TYPE=""
  62 DESKTOP_LINK=""
  63
  64 Header ()
  65 {
  66         echo "${PROGRAM} - utility to do Debian Live snapshots"
  67         echo
  68         echo "Usage: ${PROGRAM} [-c|--cow DIRECTORY] [-d|--device DEVICE] [-o|--output FILE] [-t|--type TYPE]"
  69         echo "Usage: ${PROGRAM} [-r|--resync-string STRING]"
  70         echo "Usage: ${PROGRAM} [-h|--help]"
  71         echo "Usage: ${PROGRAM} [-u|--usage]"
  72         echo "Usage: ${PROGRAM} [-v|--version]"
  73 }
  74
  75 Usage ()
  76 {
  77         MESSAGE=${1}
  78
  79         Header
  80
  81         echo
  82         echo "Try \"${PROGRAM} --help\" for more information."
  83
  84         if [ ! -z "${MESSAGE}" ]
  85         then
  86                 echo -e "${MESSAGE}"
  87                 exit 1
  88         else
  89                 exit 0
  90         fi
  91 }
  92
  93 Help ()
  94 {
  95         Header
  96
  97         echo
  98         echo "Options:"
  99         echo "  -c, --cow: specifies the copy on write directory (default: /live/cow)."
 100         echo "  -d, --device: specifies the output snapshot device (default: none)."
 101         echo "  -o, --output: specifies the output image file (default: ${type} dependent)."
 102     echo "  -r, --resync-string: internally used to resync previous made snapshots."
 103         echo "  -t, --type: specifies the snapshot type between \"squashfs\", \"ext2\", \"ext3\" or \"cpio\".gz archive (default: cpio)"
 104     echo -e "\nLook at live-snapshot(1) man page for more information."
 105
 106         exit 0
 107 }
 108
 109 Version ()
 110 {
 111         echo "${PROGRAM}, version ${VERSION}"
 112         echo
 113         echo "Copyright (C) 2006 Marco Amadori <marco.amadori@gmail.com>"
 114         echo
 115         echo "This program is free software; you can redistribute it and/or modify"
 116         echo "it under the terms of the GNU General Public License as published by"
 117         echo "the Free Software Foundation; either version 2 of the License, or"
 118         echo "(at your option) any later version."
 119         echo
 120         echo "This program is distributed in the hope that it will be useful,"
 121         echo "but WITHOUT ANY WARRANTY; without even the implied warranty of"
 122         echo "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the"
 123         echo "GNU General Public License for more details."
 124         echo
 125         echo "You should have received a copy of the GNU General Public License"
 126         echo "along with this program; if not, write to the Free Software"
 127         echo "Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA"
 128         echo
 129         echo "On Debian systems, the complete text of the GNU General Public License"
 130         echo "can be found in /usr/share/common-licenses/GPL-2 file."
 131         echo
 132         echo "Homepage: <http://debian-live.alioth.debian.org/>"
 133
 134         exit 0
 135 }
 136
 137 Do_snapshot ()
 138 {
 139         case "${TYPE}" in
 140                 squashfs)
 141                         echo "./tmp/exclude_list" > /tmp/exclude_list
 142                         ( cd "${COW}" && find . -name '*.wh.*' >> /tmp/exclude_list )
 143                         mksquashfs "${COW}" "${DEST}" -ef /tmp/exclude_list || exit 1
 144                         rm /tmp/exclude_list
 145                         ;;
 146
 147                 cpio)
 148                         ( cd "${COW}" && find . -path '*.wh.*' -prune -o -print0 | cpio --quiet -o0 -H newc | gzip -9c > "${DEST}" ) || exit 1
 149                         ;;
 150
 151                 ext2|ext3)
 152                         DU_DIM="$(du -ks ${COW} | cut -f1)"
 153                         REAL_DIM="$(expr ${DU_DIM} + ${DU_DIM} / 20)" # Just 5% more to be sure, need something more sophistcated here...
 154                         genext2fs --size-in-blocks=${REAL_DIM} --reserved-blocks=0 --root="${COW}" "${DEST}" || exit 1
 155                         ;;
 156
 157                 *)
 158                         echo "Internal error."
 159                         exit 1
 160                         ;;
 161         esac
 162 }
 163
 164 Is_same_mount ()
 165 {
 166         dir1="$(Base_path ${1})"
 167         dir2="$(Base_path ${2})"
 168
 169         if [ "${dir1}" = "${dir2}" ]
 170         then
 171                 return 0
 172         else
 173                 return 1
 174         fi
 175 }
 176
 177 Parse_args ()
 178 {
 179         # Parse command line
 180         ARGS="${1}"
 181         ARGUMENTS="$(getopt --longoptions cow:,device:,output,resync-string:,type:,help,usage,version --name=${PROGRAM} --options c:d:o:t:r:,h,u,v --shell sh -- ${ARGS})"
 182
 183         if [ "${?}" != "0" ]
 184         then
 185                 echo "Terminating." >&2
 186                 exit 1
 187         fi
 188
 189         eval set -- "${ARGUMENTS}"
 190
 191         while true
 192         do
 193                 case "${1}" in
 194                         -c|--cow)
 195                                 SNAP_COW="${2}"
 196                                 shift 2
 197                                 ;;
 198
 199                         -d|--device)
 200                                 SNAP_DEV="${2}"
 201                                 shift 2
 202                                 ;;
 203
 204                         -o|--output)
 205                                 SNAP_OUTPUT="${2}"
 206                                 shift 2
 207                                 ;;
 208
 209                         -t|--type)
 210                                 SNAP_TYPE="${2}"
 211                                 shift 2
 212                                 ;;
 213
 214                         -r|--resync-string)
 215                                 SNAP_RSTRING="${2}"
 216                                 break
 217                                 ;;
 218
 219                         -h|--help)
 220                                 Help
 221                                 ;;
 222
 223                         -u|--usage)
 224                                 Usage
 225                                 ;;
 226
 227                         -v|--version)
 228                                 Version
 229                                 ;;
 230
 231                         --)
 232                                 shift
 233                                 break
 234                                 ;;
 235
 236                         *)
 237                                 echo "Internal error."; exit 1 ;;
 238
 239                 esac
 240         done
 241 }
 242
 243 Mount_device ()
 244 {
 245         dev="${1}"
 246
 247         if [ ! -d "${MOUNTP}" ]
 248         then
 249                 mkdir -p "${MOUNTP}"
 250         fi
 251
 252         if [ -z "${dev}" ]
 253         then
 254                 # create a temp
 255                 mount -t tmpfs -o rw tmpfs "${MOUNTP}"
 256
 257                 if [ ! -L /home/${USERNAME}/Desktop/live-snapshot ]
 258                 then
 259                         ln -s "${MOUNTP}" /home/${USERNAME}/Desktop/live-snapshot
 260                 fi
 261         else
 262                 if [ -b "${dev}" ]
 263                 then
 264                         try_mount "${dev}" "${MOUNTP}" rw
 265                 fi
 266         fi
 267 }
 268
 269 Defaults ()
 270 {
 271         MOUNTP="/mnt/live-snapshot"
 272         COW="/live/cow"
 273         DEV=""
 274         DEST="${MOUNTP}/live-sn.cpio.gz"
 275         TYPE="cpio"
 276         DESKTOP_LINK=/home/${USERNAME}/Desktop/live-snapshot
 277
 278         if [ -n "${SNAP_RSTRING}" ]
 279         then
 280                 COW=$(echo "${SNAP_RSTRING}" | cut -f1 -d ':')
 281                 DEV=$(echo "${SNAP_RSTRING}" | cut -f2 -d ':')
 282                 DEST=$(echo "${SNAP_RSTRING}" | cut -f3 -d ':')
 283
 284                 case "${DEST}" in
 285                         *.cpio.gz)
 286                                 TYPE="cpio"
 287                                 ;;
 288
 289                         *.squashfs)
 290                                 TYPE="squashfs"
 291                                 ;;
 292
 293                         ""|*.ext2|*.ext3)
 294                                 TYPE="ext2"
 295                                 ;;
 296
 297                         *)
 298                                 Usage "Unregognized String"
 299                                 ;;
 300                 esac
 301         else
 302                 DEF_COW="/live/cow"
 303
 304                 # Bad options handling
 305                 if [ -z "${SNAP_COW}" ]
 306                 then
 307                         COW="${DEF_COW}"
 308                 else
 309                         COW="${SNAP_COW}"
 310                 fi
 311
 312                 case "${SNAP_TYPE}" in
 313                         "cpio"|"squashfs"|"ext2"|"ext3")
 314                                 TYPE="${SNAP_TYPE}"
 315                                 ;;
 316
 317                         "")
 318                                 TYPE="cpio"
 319                                 ;;
 320
 321                         *)
 322                                 Usage "Error: unrecognized snapshot type"
 323                                 ;;
 324                 esac
 325
 326                 #if [ -d
 327                 #if Is_same_mount
 328         fi
 329
 330         # check vars
 331         if [ ! -d "${COW}" ]
 332         then
 333                 Usage "Error: ${COW} is not a directory"
 334         fi
 335
 336         Mount_device ${DEV}
 337 }
 338
 339 Clean ()
 340 {
 341         if [ -n "${DEV}" ]
 342         then
 343                 umount "${MOUNTP}"
 344                 rmdir "${MOUNTP}"
 345                 #rm
 346         fi
 347 }
 348
 349 Main ()
 350 {
 351         Parse_args "${@}"
 352         Defaults
 353         Do_snapshot
 354         Clean
 355 }
 356
 357 Main "${@}"