# live-snapshot - utility to manage Debian Live systems snapshots
#
-# This program mount a device (fallback to /tmpfs under /mnt/snapshot
-# and save the /live/cow (or a different dir) filesystem in it for reusing
-# in another live-initramfs session. Look at manpage for more info.
+# This program mounts a device (fallback to /tmpfs under $MOUNTP
+# and saves the /live/cow (or a different directory) filesystem in it
+# for reuse in another live-initramfs session.
+# Look at the manpage for more informations.
#
-# Copyright (C) 2006 Marco Amadori <marco.amadori@gmail.com>
+# Copyright (C) 2006-2008 Marco Amadori <marco.amadori@gmail.com>
+# Copyright (C) 2008 Chris Lamb <chris@chris-lamb.co.uk>
#
-# This program is free software; you can redistribute it and/or modify
+# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
+# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# On Debian systems, the complete text of the GNU General Public License
-# can be found in /usr/share/common-licenses/GPL-2 file.
+# can be found in /usr/share/common-licenses/GPL-3 file.
-PROGRAM="$(basename $0)"
-VERSION=0.0.1
+# declare here two vars from /etc/live.conf because of "set -u"
+ROOTSNAP=""
+HOMESNAP=""
-# Source live conf
-if [ -e /etc/live.conf ]
+if [ -n "${LIVE_SNAPSHOT_CHECK_UNBOUND}" ]
then
- . /etc/live.conf
+ set -eu
else
- USERNAME=$(cat /etc/passwd | grep "999" | cut -f1 -d ':')
- HOSTNAME=$(hostname)
+ set -e
fi
-export USERNAME USERFULLNAME HOSTNAME
+. /usr/share/initramfs-tools/scripts/live-helpers
-# Source helper functions
-helpers="/usr/share/initramfs-tools/scripts/live-helpers"
+LIVE_CONF="/etc/live.conf"
+. "${LIVE_CONF}"
-if [ -e "${helpers}" ]
-then
- . "${helpers}"
-else
- echo "Error: I cannot found helper functions \"${helpers}\"."
- exit 1
-fi
+export USERNAME USERFULLNAME HOSTNAME
-# Define LSB log_* functions.
-# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
-. /lib/lsb/init-functions
+EXECUTABLE="${0}"
+PROGRAM=$(basename "${EXECUTABLE}")
+
+# Needs to be available at run and reboot time
+SAFE_TMPDIR="/live"
+
+# Permits multiple runs
+MOUNTP="$(mktemp -d -p ${SAFE_TMPDIR} live-snapshot-mnt.XXXXXX)"
+DEST="${MOUNTP}/live-sn.cpio.gz"
+DEF_SNAP_COW="/live/cow"
+TMP_FILELIST="${PROGRAM}.list"
+
+# Command line defaults and declarations
+SNAP_COW="${DEF_SNAP_COW}"
+SNAP_DEV=""
+SNAP_MNT=""
+SNAP_OUTPUT=""
+SNAP_RESYNC_STRING=""
+SNAP_TYPE="cpio"
+SNAP_LIST="/etc/live-snapshot.list"
+EXCLUDE_LIST="/etc/live-snapshot.exclude_list"
+
+Error ()
+{
+ echo "${PROGRAM}: error:" ${@}
+ exit 1
+}
-MOUNTP=""
-COW=""
-DEV=""
-DEST=""
-TYPE=""
-DESKTOP_LINK=""
+panic ()
+{
+ Error ${@}
+}
Header ()
{
- echo "${PROGRAM} - utility to do Debian Live snapshots"
+ echo "${PROGRAM} - utility to perform snapshots of Debian Live systems"
echo
- echo "Usage: ${PROGRAM} [-c|--cow DIRECTORY] [-d|--device DEVICE] [-o|--output FILE] [-t|--type TYPE]"
- echo "Usage: ${PROGRAM} [-r|--resync-string STRING]"
- echo "Usage: ${PROGRAM} [-h|--help]"
- echo "Usage: ${PROGRAM} [-u|--usage]"
- echo "Usage: ${PROGRAM} [-v|--version]"
+ echo "usage: ${PROGRAM} [-c|--cow DIRECTORY] [-d|--device DEVICE] [-o|--output FILE] [-t|--type TYPE]"
+ echo " ${PROGRAM} [-r|--resync-string STRING]"
+ echo " ${PROGRAM} [-f|--refresh]"
+ echo " ${PROGRAM} [-h|--help]"
+ echo " ${PROGRAM} [-u|--usage]"
+ echo " ${PROGRAM} [-v|--version]"
}
-Usage ()
+Help ()
{
- MESSAGE=${1}
-
Header
echo
- echo "Try \"${PROGRAM} --help\" for more information."
+ echo "Options:"
+ echo " -c, --cow: copy on write directory (default: ${SNAP_COW})."
+ echo " -d, --device: output snapshot device (default: ${SNAP_DEV:-auto})."
+ echo " -o, --output: output image file (default: ${DEST})."
+ echo " -r, --resync-string: internally used to resync previous made snapshots."
+ echo " -f, --refresh: try to sync a running snapshot."
+ echo " -t, --type: snapshot filesystem type. Options: \"squashfs\", \"ext2\", \"ext3\", \"ext4\", \"jffs2\" or \"cpio\".gz archive (default: ${SNAP_TYPE})"
+ echo
+ echo "Look at live-snapshot(1) man page for more information."
- if [ ! -z "${MESSAGE}" ]
- then
- echo -e "${MESSAGE}"
- exit 1
- else
- exit 0
- fi
+ exit 0
}
-Help ()
+Usage ()
{
Header
echo
- echo "Options:"
- echo " -c, --cow: specifies the copy on write directory (default: /live/cow)."
- echo " -d, --device: specifies the output snapshot device (default: none)."
- echo " -o, --output: specifies the output image file (default: ${type} dependent)."
- echo " -r, --resync-string: internally used to resync previous made snapshots."
- echo " -t, --type: specifies the snapshot type between \"squashfs\", \"ext2\", \"ext3\" or \"cpio\".gz archive (default: cpio)"
- echo -e "\nLook at live-snapshot(1) man page for more information."
+ echo "Try \"${PROGRAM} --help\" for more information."
exit 0
}
Version ()
{
- echo "${PROGRAM}, version ${VERSION}"
+ echo "${PROGRAM}"
echo
echo "Copyright (C) 2006 Marco Amadori <marco.amadori@gmail.com>"
+ echo "Copyright (C) 2008 Chris Lamb <chris@chris-lamb.co.uk>"
echo
echo "This program is free software; you can redistribute it and/or modify"
echo "it under the terms of the GNU General Public License as published by"
exit 0
}
-Do_snapshot ()
+Try_refresh ()
{
- case "${TYPE}" in
- squashfs)
- echo "./tmp/exclude_list" > /tmp/exclude_list
- ( cd "${COW}" && find . -name '*.wh.*' >> /tmp/exclude_list )
- mksquashfs "${COW}" "${DEST}" -ef /tmp/exclude_list || exit 1
- rm /tmp/exclude_list
- ;;
-
- cpio)
- ( cd "${COW}" && find . -path '*.wh.*' -prune -o -print0 | cpio --quiet -o0 -H newc | gzip -9c > "${DEST}" ) || exit 1
- ;;
-
- ext2|ext3)
- DU_DIM="$(du -ks ${COW} | cut -f1)"
- REAL_DIM="$(expr ${DU_DIM} + ${DU_DIM} / 20)" # Just 5% more to be sure, need something more sophistcated here...
- genext2fs --size-in-blocks=${REAL_DIM} --reserved-blocks=0 --root="${COW}" "${DEST}" || exit 1
- ;;
-
- *)
- echo "Internal error."
- exit 1
- ;;
- esac
-}
+ FOUND=""
+ if [ -n "${ROOTSNAP}" ]; then
+ "${EXECUTABLE}" --resync-string="${ROOTSNAP}"
+ FOUND="Yes"
+ fi
-Is_same_mount ()
-{
- dir1="$(Base_path ${1})"
- dir2="$(Base_path ${2})"
+ if [ -n "${HOMESNAP}" ]; then
+ "${EXECUTABLE}" --resync-string="${HOMESNAP}"
+ FOUND="Yes"
+ fi
- if [ "${dir1}" = "${dir2}" ]
+ if [ -z "${FOUND}" ]
then
- return 0
- else
- return 1
+ echo "No autoconfigured snapshots found at boot;" > /dev/null 1>&2
+ echo "(no resync string in ${LIVE_CONF})." > /dev/null 1>&2
+ exit 1
fi
}
Parse_args ()
{
# Parse command line
- ARGS="${1}"
- 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 -- ${ARGS})"
-
- if [ "${?}" != "0" ]
- then
- echo "Terminating." >&2
- exit 1
- fi
+ ARGS="${*}"
+ ARGUMENTS="$(getopt --longoptions cow:,device:,output,resync-string:,refresh,type:,help,usage,version --name=${PROGRAM} --options c:d:o:t:r:fhuv --shell sh -- ${ARGS})"
eval set -- "${ARGUMENTS}"
;;
-r|--resync-string)
- SNAP_RSTRING="${2}"
+ SNAP_RESYNC_STRING="${2}"
break
;;
+ -f|--refresh)
+ Try_refresh
+ exit 0
+ ;;
+
-h|--help)
Help
;;
;;
*)
- echo "Internal error."; exit 1 ;;
+ Error "internal error."
+ ;;
esac
done
}
-Mount_device ()
-{
- dev="${1}"
-
- if [ ! -d "${MOUNTP}" ]
- then
- mkdir -p "${MOUNTP}"
- fi
-
- if [ -z "${dev}" ]
- then
- # create a temp
- mount -t tmpfs -o rw tmpfs "${MOUNTP}"
-
- if [ ! -L /home/${USERNAME}/Desktop/live-snapshot ]
- then
- ln -s "${MOUNTP}" /home/${USERNAME}/Desktop/live-snapshot
- fi
- else
- if [ -b "${dev}" ]
- then
- try_mount "${dev}" "${MOUNTP}" rw
- fi
- fi
-}
-
Defaults ()
{
- MOUNTP="/mnt/live-snapshot"
- COW="/live/cow"
- DEV=""
- DEST="${MOUNTP}/live-sn.cpio.gz"
- TYPE="cpio"
- DESKTOP_LINK=/home/${USERNAME}/Desktop/live-snapshot
-
- if [ -n "${SNAP_RSTRING}" ]
+ # Parse resync string
+ if [ -n "${SNAP_RESYNC_STRING}" ]
then
- COW=$(echo "${SNAP_RSTRING}" | cut -f1 -d ':')
- DEV=$(echo "${SNAP_RSTRING}" | cut -f2 -d ':')
- DEST=$(echo "${SNAP_RSTRING}" | cut -f3 -d ':')
+ SNAP_COW=$(echo "${SNAP_RESYNC_STRING/\/root/${DEF_SNAP_COW}}" | cut -f1 -d ':')
+ SNAP_DEV=$(echo "${SNAP_RESYNC_STRING}" | cut -f2 -d ':')
+ SNAP_MNT=$(echo "${SNAP_RESYNC_STRING}" | cut -f3 -d ':')
+ DEST="${MOUNTP}/${SNAP_MNT}"
- case "${DEST}" in
+ case "${SNAP_MNT}" in
*.cpio.gz)
- TYPE="cpio"
+ SNAP_TYPE="cpio"
;;
*.squashfs)
- TYPE="squashfs"
+ SNAP_TYPE="squashfs"
;;
- ""|*.ext2|*.ext3)
- TYPE="ext2"
+ *.jffs2)
+ SNAP_TYPE="jffs2"
;;
- *)
- Usage "Unregognized String"
+ *.ext2|*.ext3)
+ SNAP_TYPE="ext2"
;;
- esac
- else
- DEF_COW="/live/cow"
- # Bad options handling
- if [ -z "${SNAP_COW}" ]
- then
- COW="${DEF_COW}"
- else
- COW="${SNAP_COW}"
- fi
+ "")
+ SNAP_TYPE="whole_partition"
+ ;;
+ *.ext4)
+ SNAP_TYPE="ext4"
+ ;;
+
+ *)
+ Error "unrecognized resync string"
+ ;;
+ esac
+ elif [ -z "${SNAP_OUTPUT}" ]
+ then
+ # Set target file based on image
case "${SNAP_TYPE}" in
- "cpio"|"squashfs"|"ext2"|"ext3")
- TYPE="${SNAP_TYPE}"
+ cpio)
+ DEST="${MOUNTP}/live-sn.cpio.gz"
;;
- "")
- TYPE="cpio"
+ squashfs|jffs2|ext2)
+ DEST="${MOUNTP}/live-sn.${SNAP_TYPE}"
;;
- *)
- Usage "Error: unrecognized snapshot type"
+ ext3)
+ DEST="${MOUNTP}/live-sn.ext2"
+ ;;
+
+ ext4)
+ DEST="${MOUNTP}/live-sn.ext4"
;;
esac
+ else
+ DEST="${SNAP_OUTPUT}"
+ fi
+}
+
+Validate_input ()
+{
+ case "${SNAP_TYPE}" in
+ cpio|squashfs|jffs2|ext2|ext3|ext4|whole_partition)
+ ;;
+
+ *)
+ Error "invalid filesystem type \"${SNAP_TYPE}\""
+ ;;
+ esac
- #if [ -d
- #if Is_same_mount
+ if [ ! -d "${SNAP_COW}" ]
+ then
+ Error "${SNAP_COW} is not a directory"
fi
- # check vars
- if [ ! -d "${COW}" ]
+ if [ "$(id -u)" -ne 0 ]
then
- Usage "Error: ${COW} is not a directory"
+ Error "you are not root"
fi
+}
- Mount_device ${DEV}
+Mount_device ()
+{
+ case "${SNAP_DEV}" in
+ "")
+ # create a temp
+ mount -t tmpfs -o rw tmpfs "${MOUNTP}"
+ ;;
+
+ *)
+ if [ -b "${SNAP_DEV}" ]
+ then
+ try_mount "${SNAP_DEV}" "${MOUNTP}" rw
+ fi
+ ;;
+ esac
+}
+
+Entry_is_modified ()
+{
+ # Returns true if file exists and it is also present in "cow" directory
+ # This means it is modified in respect to read-only media, so it deserve
+ # to be saved
+
+ entry="${1}"
+
+ if [ -e "${entry}" ] || [ -L "${entry}" ]
+ then
+ if [ -e "${SNAP_COW}/${entry}" ] || [ -L "${SNAP_COW}/${entry}" ]
+ then
+ return 0
+ fi
+ fi
+ return 1
+}
+
+Do_filelist ()
+{
+ # BUGS: does not handle deleted files yet
+ TMP_FILELIST=$1
+
+ if [ -f "${SNAP_LIST}" ]
+ then
+ # if SNAP_COW == /live/cow/home, SNAP_RW = /home
+ SNAP_RW="${SNAP_COW/${DEF_SNAP_COW}}"
+ if [ -z "${SNAP_RW}" ]
+ then
+ SNAP_RW="/"
+ fi
+
+ cd "${SNAP_RW}"
+ # Generate include list removing empty and commented lines
+ # and transforming paths to relatives
+ for entry in $(sed -e '/^ *$/d' -e '/^#.*$/d' -e 's#^.*$#./&#' -e 's#/\+#/#g' "${SNAP_LIST}")
+ do
+ if [ -d "${entry}" ]
+ then
+ find "${entry}" | while read line
+ do
+ if Entry_is_modified "${line}"
+ then
+ printf "%s\000" "${line}" >> "${TMP_FILELIST}"
+ fi
+ done
+ elif Entry_is_modified "${entry}"
+ then
+ # if file exists and it is modified
+ printf "%s\000" "${entry}" >> "${TMP_FILELIST}"
+ fi
+ done
+ cd "${OLDPWD}"
+
+ # echo Working dir
+ echo "${SNAP_RW}"
+ else
+ cd "${SNAP_COW}"
+ # removing whiteouts from list
+ find . -path '*.wh.*' -prune -o -print0 >> "${TMP_FILELIST}"
+ cd "${OLDPWD}"
+ # echo Working dir
+ echo "${SNAP_COW}"
+ fi
+}
+
+Do_snapshot ()
+{
+ TMP_FILELIST=$(mktemp -p "${SAFE_TMPDIR}" "${TMP_FILELIST}.XXXXXX")
+
+ case "${SNAP_TYPE}" in
+ squashfs)
+ echo ".${TMP_FILELIST}" > "${TMP_FILELIST}"
+ # Removing whiteheads of unionfs
+ cd "${SNAP_COW}"
+ find . -name '*.wh.*' >> "${TMP_FILELIST}"
+
+ if [ -e "${EXCLUDE_LIST}" ]
+ then
+ # Add explicitly excluded files
+ grep -v '^#.*$' "${EXCLUDE_LIST}" | grep -v '^ *$' >> "${TMP_FILELIST}"
+ fi
+
+ cd "${OLDPWD}"
+ mksquashfs "${SNAP_COW}" "${DEST}" -ef "${TMP_FILELIST}"
+ ;;
+
+ cpio|whole_partition)
+ if [ "${SNAP_TYPE}" = "cpio" ]
+ then
+ COPY_CMD="cpio --quiet -o0 -H newc | gzip -9c > ${DEST}"
+ else
+ COPY_CMD="cpio --quiet -pumd0 ${DEST}/"
+ fi
+
+ WORKING_DIR=$(Do_filelist "${TMP_FILELIST}")
+ cd "${WORKING_DIR}"
+ if [ -e "${EXCLUDE_LIST}" ]
+ then
+ # Convert \0 to \n and tag existing (rare but possible) \n in filenames,
+ # this to let grep -F -v do a proper work in filtering out
+ cat "${TMP_FILELIST}" | \
+ tr '\n' '\1' | \
+ tr '\0' '\n' | \
+ grep -F -v -f "${EXCLUDE_LIST}" | \
+ tr '\n' '\0' | \
+ tr '\1' '\n' | \
+ $COPY_CMD || exit 1
+ else
+ cat "${TMP_FILELIST}" | \
+ $COPY_CMD || exit 1
+ fi
+ cd "${OLDPWD}"
+ ;;
+
+ # ext2|ext3|ext4 and jffs2 does not easily support an exclude list; files
+ # should be copied to another directory in order to filter content
+ ext2|ext3|ext4)
+ DU_DIM="$(du -ks ${SNAP_COW} | cut -f1)"
+ REAL_DIM="$(expr ${DU_DIM} + ${DU_DIM} / 20)" # Just 5% more to be sure, need something more sophistcated here...
+ genext2fs --size-in-blocks=${REAL_DIM} --reserved-percentage=0 --root="${SNAP_COW}" "${DEST}"
+ ;;
+
+ jffs2)
+ mkfs.jffs2 --root="${SNAP_COW}" --output="${DEST}"
+ ;;
+ esac
+
+ if [ -f "${TMP_FILELIST}" ]
+ then
+ rm -f "${TMP_FILELIST}"
+ fi
}
Clean ()
{
- if [ -n "${DEV}" ]
+ if [ -z "${SNAP_RESYNC_STRING}" ] && echo "${DEST}" | grep -q "${MOUNTP}"
then
+ echo "${DEST} is present on ${MOUNTP}, therefore no automatic unmounting the latter." > /dev/null 1>&2
+ else
umount "${MOUNTP}"
rmdir "${MOUNTP}"
- #rm
+ fi
+}
+
+Warn_user ()
+{
+ if [ -z "${SNAP_RESYNC_STRING}" ]
+ then
+ case ${SNAP_TYPE} in
+ cpio|ext2|ext3|ext4)
+ echo "Please move ${DEST} (if is not already in it)" > /dev/null 1>&2
+ echo "in a supported writable partition (e.g ext3, vfat)." > /dev/null 1>&2
+ ;;
+
+ squashfs)
+ echo "To use ${DEST} you need to rebuild your media or add it" > /dev/null 1>&2
+ echo "to your multisession disc under the \"/live\" directory." > /dev/null 1>&2
+ ;;
+
+ jffs2)
+ echo "Please cat or flashcp ${DEST} to your partition in order to start using it." > /dev/null 1>&2
+ ;;
+ esac
+
+ if grep -qv persistent /proc/cmdline
+ then
+ echo "Remember to boot this live system with \"persistent\" specified at boot prompt." > /dev/null 1>&2
+ fi
fi
}
{
Parse_args "${@}"
Defaults
+ Validate_input
+ trap 'Clean' EXIT
+ Mount_device
Do_snapshot
- Clean
+ Warn_user
}
-Main "${@}"
+Main "${@:-}"