Fix code for absolute time

Author: benvia

install/etc/services.available/10-db-backup/run

@@ -25,8 +25,12 @@ else
         target_time=$(($current_time + $waittime))
     elif [[ $DB_DUMP_BEGIN =~ ^[0-9]+$ ]]; then
         print_debug "DB_DUMP_BEGIN is an integer."
-        waittime=$(( ${BASH_REMATCH[1]} * 60 ))
-        target_time=$(($current_time + $waittime))
+        
+        target_time=$(date --date="${today}${DB_DUMP_BEGIN}" +"%s")
+        if [[ "$target_time" < "$current_time" ]]; then
+            target_time=$(($target_time + 24*60*60))
+        fi
+        waittime=$(($target_time - $current_time))
     elif [[ $DB_DUMP_BEGIN =~ ^([0-9]{4})-([0-9]{2})-([0-9]{2})[[:space:]]([0-9]{2}):([0-9]{2}):([0-9]{2})$ ]];
     then
         # Extract year, month, day, hours, minutes, and seconds from DB_DUMP_BEGIN