#! /bin/sh
#
# dcleandb.full	This script trims the history and active file.
#		(this is the /bin/sh version of biweekly.atrim)
#		It should be run every night.
#
#		If history is not on a RAMFS, we can do a lot
#		of stuff in place and this is fast and safe.
#
#		If history IS on a RAMFS, we have to pause the server
#		while we are doing this and we have to ensure
#		that no other operations, such as an expire, are
#		in progress.  We do this by locking the .lock file
#		AND pausing the server.
#
#		In that case, if you kill this script in the middle,
#		you MUST remember to unpause the server!
#

NEWS=/news
cd $NEWS

# Make sure we have exclusive access.
if [ x"$1" != x"locked" ]
then
	dbin/plock $NEWS/.dexpirelock adm/adm-dhisexpire locked
	exit 0
fi

echo "`date` - $0 BEGIN"

DHISTORY=`dbin/dpath dhistory`
DACTIVE=`dbin/dpath server_dactive`
DB=`dbin/dpath db`

# Find out if history is on a RAMFS.
case "$DHISTORY" in
	$DB/*/*)
		RAMFS=true
		;;
	$DB/*)
		;;
	*)
		RAMFS=true
		;;
esac

if false && [ -x /usr/bin/ionice ]
then
	IONICE=ionice -c 2 -n 7
else
	IONICE=
fi

if [ "$RAMFS" = true ]
then
	# Set diablo to readonly mode.
	dbin/dicmd flush
	dbin/dicmd readonly
	dbin/dicmd flush

	# Remove the old backup
	rm -f $DB/dhistory.new
	rm -f $DB/dhistory.bak

	# Run expire.
	$IONICE dbin/dhisexpire -o0 -m $DHISTORY $DB/dhistory.new
	EXPIRESTATUS=$?

	# Pause diablo completely.
	dbin/dicmd pause
	PAUSED=true

	if [ $EXPIRESTATUS = 0 ]
	then
		# All went well, copy new file into place.
		$IONICE cp -fp $DHISTORY $DB/dhistory.bak
		if $IONICE cp -fp $DB/dhistory.new $DHISTORY
		then
			rm -f $DB/dhistory.new
		fi
		echo "History file trim succeeded:"
		ls -la $DHISTORY $DB/dhistory.bak
	else 
		# Something went wrong.
		rm -f $DB/dhistory.new
		echo "Unable to trim $DHISTORY file"
	fi
else
	# Pause anyway, because sometimes running diablo processes
	# do not reopen the history file. Need to look into this.
	dbin/dicmd flush
	dbin/dicmd readonly
	dbin/dicmd flush

	# Standard expire run.
	dbin/dhisexpire -a $DHISTORY

	dbin/dicmd pause
	PAUSED=true
fi

# Trim the active file.
dbin/dkp -t $DACTIVE

# Resume diablo in case we paused it.
if [ "$PAUSED" = true ]
then
	dbin/dicmd go
fi

echo "`date` - $0 END"