harvey/rc/bin/replica/pull

#!/bin/rc

rfork en

fn usage {
	echo 'usage: replica/pull [-nv] [-c name] [-s name] replica-name [paths]' >[1=2]
	exit usage
}

. /rc/bin/replica/defs $*

need clientlog serverlog clientdb clientroot serverroot

# mount the server file system, update the log
must servermount
must serverupdate
must clientmount

# download the log
n=`{ls -l $clientlog >[2]/dev/null |awk '{print $6}'}
s=`{ls -l $serverlog >[2]/dev/null |awk '{print $6}'}
if(~ $n 0 || ~ $#n 0 || test $s -lt $n){
	if(test -e $clientlog) must rm $clientlog
	must fcp $serverlog $clientlog
}
if not{
	m=`{echo $n-1024 | hoc}
	if(~ $m -*)
		m=0
	cmp -s $serverlog $clientlog $m $m
	x=$status
	switch($x){
	case *': EOF'
		must tail +^$n^c $serverlog >>$clientlog
	case *': differ'
		must rm $clientlog
		must fcp $serverlog $clientlog
	case ''
		;
	case *
		fatal cmp: $x
	}
}

# normally we'd do this after applylog, but we want
# applylog to be the last thing in this script, so we'll
# do it here instead, compacting changes from the
# _last_ applylog.

ndb=`{echo $clientdb | sed 's;(.*)/(.*);\1/_\2;'}
must replica/compactdb $clientdb >$ndb
mv $ndb $clientdb

# mount the client file system, apply the log
# this is the last thing in the script and is execed so that
# if replica/pull is overwritten nothing bad will happen.
# applylog takes care of itself as far as protection against being overwritten.
exec replica/applylog $opt $applyopt $clientdb $clientroot $serverroot $paths <$clientlog