Add option to use local time instead of UTC

Closes #17, closes #18.

README.md

@@ -47,7 +47,6 @@ Notes on behaviour:
     -   Keep the most recent 12 monthly backups, and delete any older
         ones.
     -   Do not delete any yearly backups.
--   Times in archive names use UTC, not the server's timezone.
 
 TODO
 ----

acts

@@ -71,6 +71,7 @@ fi
 # Use default values if anything is not set
 verbose="${verbose=0}"
 hostname="${hostname=$(hostname -s)}"
+uselocaltime="${uselocaltime=0}"
 backuptargets="${backuptargets=}"
 prebackupscript="${prebackupscript=}"
 postbackupscript="${postbackupscript=}"
@@ -84,6 +85,14 @@ if [ -z "$backuptargets" ] ; then
     die "config-error message=\"\$backuptargets is not set in acts.conf.\""
 fi
 
+if [ "$uselocaltime" = 0 ] ; then
+  utc="-u"
+elif [ "$uselocaltime" = 1 ] ; then
+  utc=""
+else
+  die "config-error message=\"invalid \$uselocaltime in acts.conf; valid options are 0 (for UTC) or 1 (for local time).\""
+fi
+
 # Create the lock. mkdir is atomic test/set, so use that instead of the typical test -f/touch combo
 if [ -d "$lockfile" ] ; then
     die "acts-error message=\"$lockfile exists referencing PID $(cat "$lockfile/pid" 2>/dev/null || echo "<none>"). Hint: If acts is not already running, rm -rf $lockfile.\""
@@ -108,7 +117,7 @@ archives=$(echo "$archives_unsorted" | sort -n)
 
 # When is now?
 # Instead of re-running date, be paranoid the day was microseconds away from ending
-today=$(date -u "+%Y-%m-%d_%H:%M:%S")
+today=$(date "$utc" "+%Y-%m-%d_%H:%M:%S")
 year=$(echo "$today" | cut -d_ -f1 | cut -d- -f1)
 month=$(echo "$today" | cut -d_ -f1 | cut -d- -f2)
 # day=$(echo "$today" | cut -d_ -f1 | cut -d- -f3) # unused

acts.conf.sample

@@ -29,6 +29,11 @@ verbose=1
 # Default: $(hostname -s)
 #hostname=$(hostname)
 
+# uselocaltime
+# Use local time instead of UTC for the archive date and timestamps.
+# Default: 0 (i.e. use UTC)
+#uselocaltime=1
+
 # prebackupscript
 # This script is run before backups are created. Make sure it's executable.
 # Default: unset