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