Index: user/cperciva/freebsd-update-build/build-upgrade-patches.sh
===================================================================
--- user/cperciva/freebsd-update-build/build-upgrade-patches.sh	(revision 365678)
+++ user/cperciva/freebsd-update-build/build-upgrade-patches.sh	(revision 365679)
@@ -1,80 +1,100 @@
 #!/bin/sh
 
 if [ $# -lt 3 ]; then
 	echo "usage: $0 ARCH TARGETREL OLDRELS"
 	exit 1
 fi
 
+while [ $(ls -d ${TMPDIR:-/tmp}/genpatch* 2>/dev/null | wc -l) -gt 0 ]; do
+	echo "There appears to be evidence from previous runs in ${TMPDIR:-/tmp}/genpatch*...bailing"
+	exit 1
+done
+
 BASEDIR=/usr/freebsd-update-server
 ARCH=$1
 TARGETREL=$2
 OLDRELS=$3
 
 WWWDIR=${BASEDIR}/pub
 
 MAXJOBS=$(( $(sysctl -n hw.ncpu) - 2 ))
 if [ $MAXJOBS -lt 1 ]; then
 	MAXJOBS=1
 fi
 
 genpatch() {
 	tempdir=$(mktemp -d -t genpatch)
 
 	gunzip < ${WWWDIR}/${OR}/${ARCH}/f/${OH}.gz > ${tempdir}/${OH}
 	gunzip < ${WWWDIR}/${NR}/${ARCH}/f/${NH}.gz > ${tempdir}/${NH}
-	bsdiff ${tempdir}/${OH} ${tempdir}/${NH} ${WWWDIR}/to-${TARGETREL}/${ARCH}/bp/${OH}-${NH}
+	bsdiff ${tempdir}/${OH} ${tempdir}/${NH} ${tempdir}/${OH}-${NH}
+	if [ $? -eq 0 ]; then
+		mv ${tempdir}/${OH}-${NH} ${WWWDIR}/to-${TARGETREL}/${ARCH}/bp/${OH}-${NH}
+	else
+		echo "Error generating patch ${OH}-${NH}, removing"
+		rm ${tempdir}/${OH}-${NH}
+	fi
+
 	rm ${tempdir}/${OH} ${tempdir}/${NH}
 	rmdir ${tempdir}
 }
 
 echo -n "Building hash table..."
 mkdir -p ${WWWDIR}/to-${TARGETREL}/${ARCH}/bp/
 for V in ${OLDRELS}; do
 	zcat ${WWWDIR}/${V}/${ARCH}/m/* |
 	    cut -f 3,4,9 -d '|' |
 	    fgrep '|f|' |
 	    cut -f 1,3 -d '|' |
 	    sort -u |
 	    grep -E '\|[0-9a-f]{64}' |
 	    lam -s "${V}|" -
 done |
     sort -k 2,2 -t '|' > hashtab
 echo "done"
 
 echo "Starting patch generation"
+marker=
 zcat ${WWWDIR}/${TARGETREL}/${ARCH}/m/* |
     cut -f 3,4,9 -d '|' |
     fgrep '|f|' |
     cut -f 1,3 -d '|' |
     sort -u |
     grep -E '\|[0-9a-f]{64}' |
     lam -s "${TARGETREL}|" - |
     sort -k 2,2 -t '|' |
     join -1 2 -2 2 -t '|' hashtab - |
     cut -f 2- -d '|' |
     sort -k 2,2 -t '|' |
     tr '|' ' ' |
     while read OR OH NR NH; do
+	if [ "$(echo ${OH} | cut -c1)" != "$marker" ]; then
+		echo "  working on $(echo ${OH} | cut -c1-4)...."
+		marker="$(echo ${OH} | cut -c1)"
+	fi
+
 	if [ -f ${WWWDIR}/to-${TARGETREL}/${ARCH}/bp/${OH}-${NH} ]; then
 		continue
 	fi
 	if [ ${OH} = ${NH} ]; then
 		continue
 	fi
 
 	genpatch &
 
 	jobs="$(jobs)"
 	numjobs=$(echo "$jobs" | wc -l)
 	while [ $numjobs -ge $MAXJOBS ]; do
 		sleep 2
 
 		jobs="$(jobs)"
 		numjobs=$(echo "$jobs" | wc -l)
 	done
     done
 
 echo -n "Finished spawning children, waiting for them to finish..."
-wait
+while [ $(ls -d ${TMPDIR:-/tmp}/genpatch* 2>/dev/null | wc -l) -gt 0 ]; do
+	sleep 2
+done
 echo "done"
 rm hashtab