grflog: fix, add truncate

gluster/grflog

 #!/bin/sh
 
-RES=pub
-VOLUME=ftp-$RES
+VOLUME=ftp-pub
+[ -n "$1" ] && VOLUME="$1" && shift
+
+RES=${VOLUME/ftp-}
 LOCALPATH=/var/ftp/$RES
+
 GLUSTERLOG=/var/log/glusterfs/var-ftp-$RES.log
+# server hack
 [ "$RES" = "pub" ] && GLUSTERLOG=/var/log/glusterfs/var-ftppub-pub.log
 
+[ -n "$1" ] && GLUSTERLOG="$1" && shift
 
 grep_dht_log()
 {
@@ -15,6 +20,7 @@ grep_dht_log()
 
 # use mount
 grep_dht_log $GLUSTERLOG | sed -e "s|.*dht_lookup_everywhere_cbk\] 0-\($VOLUME\)-dht: \(.*\)|\1: \2|g" > $0.$VOLUME.log
+truncate -c -s0 $GLUSTERLOG
 sort -u < $0.$VOLUME.log >$0.$VOLUME.sorted.log
 
 TASKFILE=$0.task