Rotate old .0 log files when migrating from sysklogd. Closes: #491672

1 files changed, 42 insertions, 0 deletions

diff --git a/debian/rsyslog.postinst b/debian/rsyslog.postinst
index 1df6726..8d93582 100644
--- a/debian/rsyslog.postinst
+++ b/debian/rsyslog.postinst
@@ -14,8 +14,50 @@ set -e
 # for details, see http://www.debian.org/doc/debian-policy/ or
 # the debian-policy package
 
+rotate_old_log_files()
+{
+	log_files="syslog mail.info mail.warn mail.err mail.log daemon.log \
+	           kern.log auth.log user.log lpr.log cron.log debug messages"
+	skipped_files=""
+	dir=/var/log
+
+	for f in $log_files; do
+		if [ -e $dir/$f.0 ]; then
+			rotate="yes"
+			if [ -e $dir/$f.1.gz ]; then
+				date0=$(stat --format=%Y $dir/$f.0)
+				date1=$(stat --format=%Y $dir/$f.1.gz)
+				if [ $date0 -lt $date1 ] ; then
+					# .0 log file is older than .1
+					skipped_files="$dir/$f.0\n$skipped_files"
+					rotate="no"
+				fi
+			fi
+			if [ "$rotate" = "yes" ] ; then
+				for s in $(seq 9 -1 1) ; do
+					if [ -e $dir/$f.$s.gz ]; then
+						mv $dir/$f.$s.gz $dir/$f.$((s+1)).gz
+					fi
+				done
+				mv $dir/$f.0 $dir/$f.1
+			fi
+		fi
+	done
+	if [ -n "$skipped_files" ]; then
+		printf "The following old log files were found which could not be rotated safely.\n"
+		printf "\n$skipped_files\n"
+		printf "Please inspect them manually and delete them, if no longer required.\n"
+	fi
+}
+
+
 case "$1" in
     configure)
+	# Rotate .0 log files when migrating from sysklogd
+	if dpkg --compare-versions "$2" lt "3.18.5-1"; then
+		rotate_old_log_files
+	fi
+
 	# Stop the service on upgrades before it is started again.
 	# dh_installinit -r will create the start code.
 	if [ -n "$2" ]; then