plan9fox/sys/lib/lp/daemon/generic

#!/bin/rc
rfork s

if (! ~ $DEBUG '') flag x +

LPDELAY=60

if (! ~ $#* 2 && ! ~ $#* 3) {
	echo 'usage generic local_cmd _remote_cmd [ success_cmd ]' >[1=2]
	exit 'argument count'
}
LOCAL_CMD=$1
REMOTE_CMD=$2
SUCCESS_CMD=$3

# we don't want to make a LOCK file unless we are at the destination
# let the spooler take care of moving it there
# this is necessary for clients and servers that share the
# same name space
if (! ~ $THIS_HOST $DEST_HOST || ! LOCK $LPSPOOL/$LPDEST/LOCK $sysname $pid) exit ''

cd $LPSPOOL

MAXTRY=2
PRINTLOG=$LPLOGDIR/$LPDEST^.st

fn schedule{
	FILE=`{
		@{
			rfork n
			bind -b $LPLIB/sched /bin
			$SCHED $LPDEST
		}
	}
}

while (schedule; ! ~ $#FILE 0) {
	SCHEDLINE=`{cat $LPDEST/$FILE(1)^id}
	LSLINE=`{ls -l $LPDEST/$FILE(1)}
	if (! test -s $LPDEST/.seqno) {
		echo 0 > $LPDEST/.seqno
	}
	if not {
		LPSEQNO = `{cat $LPDEST/.seqno | awk '{seqno = $1 + 1; if (seqno > 999) seqno = 0; print seqno}'}
		echo $LPSEQNO > $LPDEST/.seqno
	}
	STARTIME=`{date}
	if (! test -s $LPDEST/$FILE(1)) {
		echo $SCHEDLINE(2)$SCHEDLINE(4)'	'$SCHEDLINE(3)	$SCHEDLINE(5)' ! '$LSLINE(6) $STARTIME(4) >> $LPLOG
		rm -f $LPDEST/$FILE $LPDEST/$FILE^id
	}
	if not {
		if (~ $THIS_HOST $DEST_HOST) {
			if (test -f $LPLIB/perm/$LPDEST && grep -s $SCHEDLINE(2) $LPLIB/perm/$LPDEST) {
				echo you are not allowed to use printer $LPDEST | mail $SCHEDLINE(2)
				rm -f $LPDEST/$FILE(1) $LPDEST/$FILE(1)^id
			}
			if not {
				> $PRINTLOG
				STARTIME=`{date}
				eval $LOCAL_CMD
				rv=$status
				ENDTIME=`{date}
				status=$rv
				if () {
					echo $SCHEDLINE(1)^$SCHEDLINE(3)'	'$SCHEDLINE(2)'	'$SCHEDLINE(4)' + '$LSLINE(6)' '$STARTIME(4)' '$ENDTIME(4)
					eval $SUCCESS_CMD
					rm -f $LPDEST/$FILE(1) $LPDEST/$FILE(1)^id
				}
				if not {
					echo $SCHEDLINE(1)^$SCHEDLINE(3)'	'$SCHEDLINE(2)'	'$SCHEDLINE(4)' - '$LSLINE(6)' '$STARTIME(4)' '$ENDTIME(4)' status='$rv
					THISTRY=`{echo $SCHEDLINE(4) + 1|hoc}
					echo $SCHEDLINE(1) $SCHEDLINE(2) $SCHEDLINE(3) $THISTRY >$LPDEST/$FILE(1)^id
					if (test $THISTRY -ge $MAXTRY) {
						if (test -d $LPLIB/prob/$LPDEST) {
							cp $LPDEST/$FILE(1) $LPLIB/prob/$LPDEST
							cp $LPDEST/$FILE(1)^id $LPLIB/prob/$LPDEST
							cp $PRINTLOG $LPLIB/prob/$LPDEST/$FILE(1)^log
						}
						upasname=daemon
						mail $SCHEDLINE(2) <<endmail1
						rm -f $LPDEST/$FILE(1) $LPDEST/$FILE(1)^id
					}
					if not {
						touch $LPDEST/$FILE(1)
						sleep $LPDELAY
					}
				}
			}
		}
		if not {
# we don't want to be here
#			trap '' 13	# temp hack: ignore SIGPIPE
			STARTIME=`{date}
			eval $REMOTE_CMD 
			rv=$status
			ENDTIME=`{date}
			if (~ $rv '') {
				echo $SCHEDLINE(1)^$SCHEDLINE(3)'	'$SCHEDLINE(2)'	'$SCHEDLINE(4)' + '$LSLINE(6)' '$STARTIME(4)' '$ENDTIME(4)
				rm -f $LPDEST/$FILE(1) $LPDEST/$FILE(1)^id
			}
			if not {
				echo $SCHEDLINE(1)^$SCHEDLINE(3)'	'$SCHEDLINE(2)'	'$SCHEDLINE(4)' - '$LSLINE(6)' '$STARTIME(4)' '$ENDTIME(4)
				echo status $rv from '$REMOTE_CMD'
				THISTRY=`{echo $SCHEDLINE(4) + 1|hoc}
				echo $SCHEDLINE(1) $SCHEDLINE(2) $SCHEDLINE(3) $THISTRY >$LPDEST/$FILE(1)^id
				if (~ $THISTRY $MAXTRY) {
					upasname=daemon
					mail $SCHEDLINE(2) <<endmail2
				}
				if not {
					touch $LPDEST/$FILE(1)
					sleep $LPDELAY

				# this is here to deal with running out of
				# Datakit channels or other stupid problems
				# backoff connection attempts but not too long
					LPDELAY=`{echo $LPDELAY '*' 2|hoc}
					if (test $LPDELAY -gt 960)
						LPDELAY=60
				}
			}
		}
	}
}
Your job has failed to print on $LPDEST after $MAXTRY attempt(s).
If the directory $LPLIB/prob/$LPDEST exists on $DEST_HOST,
the file has been put there along with the printer log file.
			Your friendly printer daemon
endmail1
Your job has failed to print on $LPDEST after $MAXTRY attempt(s).
There is a problem in sending the job to $DEST_HOST,
but I'll keep trying.  Have a nice day.
			Your enthusiastic printer daemon
endmail2
UNLOCK $LPSPOOL/$LPDEST
rm $LPSPOOL/$LPDEST >[2]/dev/null