From 0deeb585014a684b6e5c5b3a05788a081534a900 Mon Sep 17 00:00:00 2001
From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Fri, 5 Nov 2021 14:51:33 +1100
Subject: [PATCH] added snapshot comparison browse tool

---
 ssbrowse.sh | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100755 ssbrowse.sh

diff --git a/ssbrowse.sh b/ssbrowse.sh
new file mode 100755
index 0000000..82a7b37
--- /dev/null
+++ b/ssbrowse.sh
@@ -0,0 +1,90 @@
+#!/bin/bash
+#
+# Browse snapshots of a given path and run meld to compare with
+# current directory
+# $1: path -- into mounted nilfs
+# $2: [path] -- to compare with
+
+## Prepare for mounting of snapshots
+MOUNT=/tmp/ssmeld-$$
+mkdir -p $MOUNT || exit 1
+
+function exitbrowse() {
+    umount $MOUNT 2>/dev/null
+    rmdir -f $MOUNT
+    trap "" 0
+}
+trap "exitbrowse" 0 2 9 15
+
+DF=( $(df $1 | awk '{d=$1;p=$NF;} END {printf "%s %s", d, p;}') )
+
+NILFSROOT=${DF[1]}
+NILFSDEV=${DF[0]}
+PTR="${1#$NILFSROOT}"
+DIR0=$MOUNT$PTR
+DIR1=$NILFSROOT
+
+function snap2iselect() {
+    lscp -r -s $NILFSDEV  | while read CNO DATE TIME REST ; do
+	[ $CNO = CNO ] && continue
+	echo "  <s:$CNO> [$CNO] ${DATE} ${TIME}"
+    done
+}
+
+function dirof() {
+    x="${1%%|*}"
+    x="${x%%(*}"
+    echo "${x}" | sed 's/\(\S\+\s\+\)\{8\}//;s/\s*$//'
+}
+
+function dirsdiff() {
+    while true ; do
+	LEFT="$(cd $DIR0/${1#/} && ls -l)"
+	RIGHT="$(cd $DIR1/${1#/} && ls -l)"
+	SEL="$(diff -W 500 -y --left-column <(echo "$LEFT") <(echo "$RIGHT")| \
+	     column -t | \
+	     iselect -n "($CNO ~ $DIR1)" -K -kd -kx -kz -a -t "${1-/}" )"
+	KEY="${SEL%%:*}"
+	SEL="${SEL#*:}"
+	[ -z "$SEL" ] && break
+	case "$KEY" in
+	    RETURN|KEY_RIGHT)
+		ZEL="$(echo "${SEL}" | sed 's/^>\s*//;s/\s*$//')"
+		if [ -z "${ZEL##d*}" ] ; then
+		    D="$(dirof "$ZEL")"
+		    dirsdiff "$1/$D" || return 1
+		else
+		    D="$(dirof "$ZEL")"
+		    diff -D "$CNO" -N $DIR0/${1#/}/$D $DIR1/${1#/}/$D |\
+			less
+			 
+		fi
+		;;
+	    d) # Find next dept-first difference 
+		:
+		;;
+	    x) # Exit
+		return 1
+		;;
+	    *)
+		echo "*** ${KEY}:${SEL}"
+		read x
+		;;
+	esac
+    done
+}
+
+N=2
+while true ; do
+    SNAPS="$(snap2iselect)"
+    CNO="$(iselect -n "($DIR1/)" \
+		  -t "Snapshots for $NILFSDEV=$NILFSROOT" -p $N -P \
+		  "Select snapshot" "$SNAPS")"
+    [ -z "$CNO" ] && break
+    N=${CNO%%:*}
+    CNO=${CNO#*:}
+    if sudo mount -t nilfs2 -oro,cp=$CNO $NILFSDEV $MOUNT ; then
+	dirsdiff /
+	sudo umount $MOUNT
+    fi
+done
-- 
2.39.2