From d5a9dc104fa5705a2c173a60c8c6b742c8c3ee50 Mon Sep 17 00:00:00 2001
From: Marco Amadori <marco.amadori@gmail.com>
Date: Fri, 6 Jun 2008 23:23:55 +0200
Subject: [PATCH] live-snapshot: new "--refresh" option.

* "--refresh" explicitly saves status of boot-time auto-discovered snapshots
  without rebooting.
---
 bin/live-snapshot               | 41 ++++++++++++++++++++++++++++++++++++++---
 manpages/live-snapshot.en.1.txt |  6 ++++++
 manpages/live-snapshot.it.1.txt |  6 ++++++
 3 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/bin/live-snapshot b/bin/live-snapshot
index 7e68c59..67e853a 100755
--- a/bin/live-snapshot
+++ b/bin/live-snapshot
@@ -26,14 +26,21 @@
 # On Debian systems, the complete text of the GNU General Public License
 # can be found in /usr/share/common-licenses/GPL-2 file.
 
+# declare here two vars from /etc/live.conf because of "set -u"
+ROOTSNAP=""
+HOMESNAP=""
+
 set -eu
 
 . /usr/share/initramfs-tools/scripts/live-helpers
-. /etc/live.conf
+
+LIVE_CONF="/etc/live.conf"
+. "${LIVE_CONF}"
 
 export USERNAME USERFULLNAME HOSTNAME
 
-PROGRAM="$(basename $0)"
+EXECUTABLE="${0}"
+PROGRAM=$(basename "${EXECUTABLE}")
 
 # Needs to be available at run and reboot time
 SAFE_TMPDIR="/live"
@@ -66,6 +73,7 @@ Header ()
 	echo
 	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]"
@@ -81,6 +89,7 @@ Help ()
 	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\", \"jffs2\" or \"cpio\".gz archive (default: ${SNAP_TYPE})"
 	echo
 	echo "Look at live-snapshot(1) man page for more information."
@@ -127,11 +136,32 @@ Version ()
 	exit 0
 }
 
+Try_refresh ()
+{
+	FOUND=""
+	if [ -n "${ROOTSNAP}" ]; then
+		"${EXECUTABLE}" --resync-string="${ROOTSNAP}"
+		FOUND="Yes"
+	fi
+
+	if [ -n "${HOMESNAP}" ]; then
+		"${EXECUTABLE}" --resync-string="${HOMESNAP}"
+		FOUND="Yes"
+	fi
+
+	if [ -z "${FOUND}" ]
+	then
+		echo "No autoconfigured snapshots found at boot;" > /dev/null 1>&2
+		echo "(no resync string in ${LIVE_CONF})." > /dev/null 1>&2
+		exit 1
+	fi
+}
+
 Parse_args ()
 {
 	# Parse command line
 	ARGS="${*}"
-	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 -- ${ARGS})"
+	ARGUMENTS="$(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}"
 
@@ -163,6 +193,11 @@ Parse_args ()
 				break
 				;;
 
+			-f|--refresh)
+				Try_refresh
+				exit 0
+				;;
+
 			-h|--help)
 				Help
 				;;
diff --git a/manpages/live-snapshot.en.1.txt b/manpages/live-snapshot.en.1.txt
index e880b08..fdca25b 100644
--- a/manpages/live-snapshot.en.1.txt
+++ b/manpages/live-snapshot.en.1.txt
@@ -55,6 +55,12 @@ the filename/label used for the output file/partition. If left blank, live-snaps
 
 internally used on resyncs.
 
+  -f, --refresh::
+
+try to do the same operation that should be done at reboot or halt, resyncing
+boot-time auto discovered snapshots. Useful to prevent a crash or surge
+power-off.
+
   -t, --type **TYPE**::
 
 Type could be one of "cpio", "squashfs", "ext2", "ext3" or "jffs2".
diff --git a/manpages/live-snapshot.it.1.txt b/manpages/live-snapshot.it.1.txt
index e396efe..3892bed 100644
--- a/manpages/live-snapshot.it.1.txt
+++ b/manpages/live-snapshot.it.1.txt
@@ -61,6 +61,12 @@ del device oppure user`a l'intera partizione.
 usato internamente nelle sincronizzazioni dallo script di init di
 live-initramfs. Il formato pu\`o cambiare, usatelo a vostro rischio.
 
+  -f, --refresh::
+
+scatena la stessa operazione che verrebbe fatta al reboot o all'halt della
+macchina, provando a fare il resync degli snapshot trovati al boot, usabile
+per salvare le modifiche in vista di un crash o di una mancanza di corrente.
+
   -t, --type **TYPE**::
 
 il tipo pu`o essere "cpio", "squashfs" o "ext2".
-- 
2.1.4