X-Git-Url: http://git.grml.org/?a=blobdiff_plain;f=bin%2Flive-snapshot;h=3d4efad0da20bdb3c9adcb8f26083b7013b9403d;hb=ef3cb9d56ba76727af70a0ddab65edc73a7cdbd9;hp=67e853aa55578a3e05da13296166970ce4899670;hpb=d5a9dc104fa5705a2c173a60c8c6b742c8c3ee50;p=live-boot-grml.git

diff --git a/bin/live-snapshot b/bin/live-snapshot
index 67e853a..3d4efad 100755
--- a/bin/live-snapshot
+++ b/bin/live-snapshot
@@ -3,15 +3,16 @@
 # live-snapshot - utility to manage Debian Live systems snapshots
 #
 #   This program mounts a device (fallback to /tmpfs under $MOUNTP
-#   and saves the /live/cow (or a different dir) filesystem in it for reuse
-#   in another live-initramfs session. Look at manpage for more info.
+#   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) 2006-2008 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,
@@ -20,17 +21,21 @@
 # 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.
 
 # declare here two vars from /etc/live.conf because of "set -u"
 ROOTSNAP=""
 HOMESNAP=""
 
-set -eu
+if [ -n "${LIVE_SNAPSHOT_CHECK_UNBOUND}" ]
+then
+	set -eu
+else
+	set -e
+fi
 
 . /usr/share/initramfs-tools/scripts/live-helpers
 
@@ -48,13 +53,17 @@ 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="/live/cow"
+SNAP_COW="${DEF_SNAP_COW}"
 SNAP_DEV=""
 SNAP_OUTPUT=""
 SNAP_RESYNC_STRING=""
 SNAP_TYPE="cpio"
+SNAP_LIST="/etc/live-snapshot.list"
+EXCLUDE_LIST="/etc/live-snapshot.exclude_list"
 
 Error ()
 {
@@ -312,23 +321,114 @@ Mount_device ()
 	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 "${entry}" ]
+	then
+		if [ -e "${DEF_SNAP_COW}/${entry}" ] || [ -L "${DEF_SNAP_COW}/${entry}" ]
+		then
+			return 0
+		fi
+	fi
+	return 1
+}
+
+Do_filelist ()
+{
+	# BUGS: supports only cpio.gz types, and does not handle deleted files yet
+
+	TMP_FILELIST=$1
+	if [ -f "${SNAP_LIST}" ]
+	then
+		# Generate include list removing empty and commented lines
+		for entry in $(sed -e '/^ *$/d' -e '/^#.*$/d' "${SNAP_LIST}")
+		do
+			if [ -d "${entry}" ]
+			then
+				cd /
+				find "${entry}" | while read line
+				do
+					if Entry_is_modified "${line}"
+					then
+						printf "%s\000" "${line}" >> "${TMP_FILELIST}"
+					fi
+				done
+				cd "${OLDPWD}"
+			elif Entry_is_modified "${entry}"
+			then
+				# if file exists and it is modified
+				printf "%s\000" "${entry}" >> "${TMP_FILELIST}"
+			fi
+		done
+
+		if [ "${SNAP_COW}" = "${DEF_SNAP_COW}" ]
+		then
+			# Relative to rootfs
+			echo "/"
+		else
+			# Mostly "/home"
+			echo "${SNAP_COW}"
+		fi
+	else
+		cd "${SNAP_COW}"
+		find . -path '*.wh.*' -prune -o -print0 >> "${TMP_FILELIST}"
+		cd "${OLDPWD}"
+		echo "${SNAP_COW}"
+	fi
+}
+
 Do_snapshot ()
 {
+	TMP_FILELIST=$(mktemp -p "${SAFE_TMPDIR}" "${TMP_FILELIST}.XXXXXX")
+
 	case "${SNAP_TYPE}" in
 		squashfs)
-			EXCLUDE_LIST="$(mktemp -p ${SAFE_TMPDIR} live-snapshot-exclude-list.XXXXXX)"
-			echo "./${EXCLUDE_LIST}" > "${EXCLUDE_LIST}"
+			echo ".${TMP_FILELIST}" > "${TMP_FILELIST}"
+			# Removing whiteheads of unionfs
 			cd "${SNAP_COW}"
-			find . -name '*.wh.*' >> "${EXCLUDE_LIST}"
+			find . -name '*.wh.*' >> "${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 "${EXCLUDE_LIST}"
-			rm -f "${EXCLUDE_LIST}"
+			mksquashfs "${SNAP_COW}" "${DEST}" -ef "${TMP_FILELIST}"
 			;;
 
 		cpio)
-			( cd "${SNAP_COW}" && find . -path '*.wh.*' -prune -o -print0 | cpio --quiet -o0 -H newc | gzip -9c > "${DEST}" ) || exit 1
+			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' | \
+					cpio --quiet -o0 -H newc | \
+					gzip -9c > "${DEST}" || exit 1
+			else
+				cat "${TMP_FILELIST}" | \
+					cpio --quiet -o0 -H newc | \
+					gzip -9c > "${DEST}" || exit 1
+			fi
+			cd "${OLDPWD}"
 			;;
 
+		# ext2|ext3 and jffs2 does not easily support an exclude list; files
+		# should be copied to another directory in order to filter content
 		ext2|ext3)
 			DU_DIM="$(du -ks ${SNAP_COW} | cut -f1)"
 			REAL_DIM="$(expr ${DU_DIM} + ${DU_DIM} / 20)" # Just 5% more to be sure, need something more sophistcated here...
@@ -339,6 +439,11 @@ Do_snapshot ()
 			mkfs.jffs2 --root="${SNAP_COW}" --output="${DEST}"
 			;;
 	esac
+
+	if [ -f "${TMP_FILELIST}" ]
+	then
+		rm -f "${TMP_FILELIST}"
+	fi
 }
 
 Clean ()
@@ -352,6 +457,33 @@ Clean ()
 	fi
 }
 
+Warn_user ()
+{
+	if [ -z "${SNAP_RESYNC_STRING}" ]
+	then
+		case ${SNAP_TYPE} in
+			cpio|ext2|ext3)
+				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 ${DEST} to your partition in order to start using it." > /dev/null 1>&2
+				;;
+		esac
+
+		if grep -qv persistent /proc/cmdline
+		then
+			echo "Remember to boot this live system with \"persistent\" specified at boot prompt." > /dev/null 1>&2
+		fi
+	fi
+}
+
 Main ()
 {
 	Parse_args "${@}"
@@ -360,6 +492,7 @@ Main ()
 	trap 'Clean' EXIT
 	Mount_device
 	Do_snapshot
+	Warn_user
 }
 
 Main "${@:-}"