#!/bin/sh -e

PATH=/bin:/sbin:/usr/bin:/usr/sbin

mp="/tmp/upgrade.$$"
image='newimage'
cfg='/etc/upgrade.conf'
progs='/bin/dd /bin/kill /bin/sh /bin/sleep /libexec/ld-elf.so.1 /sbin/init'

roundup() { echo $(( (($1+256)/512+1)*512 )); }

load_files() {
  local bdir f

  for f
  do
    bdir=${f%/*}
    mkdir -p $mp$bdir
    cp -p $f $mp$bdir/
  done
}

#
# Main
#

[ -r $cfg ] && . $cfg || { echo $0: cannot read $cfg; exit 1; }
export FTP_USER FTP_PASSWORD HTTP_AUTH

echo "Verifying $url"
size=$(fetch -s "$url")

if [ -z "$size" -o "$size" = Unknown ]; then
  echo Failed >&2
  exit 1
fi

echo Size: $size bytes
size=$(roundup $size)

depends=$(ldd -f '%p\n' $progs 2>/dev/null | sort -u)
for f in $progs $depends
do
  size=$(( $size + $(roundup `stat -f '%z' $f`) ))
done
size=$(($size*6/5))

echo Allocating $(($size/1024))K for memory disk
if ! md=$(mdconfig -at malloc -o reserve -s ${size}b); then
  echo Failed to allocate $size bytes >&2
  exit 1
fi

md=/dev/$md
mkdir -p $mp; [ -d $mp ] || exit 1

newfs -O1 -b 4096 -f 512 -m 0 -o space $md >/dev/null
mount -o async $md $mp
cd $mp
mkdir dev etc
load_files $progs $depends
cp -p /etc/rc.upgrade etc/rc
# silence init(8) moaning "login_getclass: unknown class"
cp -p /etc/login.conf.db etc

bsize=$(geom map list | awk '/Stripesize:/ {print $2; exit}')
iseek=''; off=''; skip=0; stage=1
{
  echo '#!/bin/sh -e'
  for part in $layout
  do
    size=$(sysctl kern.geom.conftxt | awk '$3=="map/'$part'" {print $4}')
    blocks=$(($size/$bsize))
    [ -z "$off" ] && off=$(sysctl kern.geom.conftxt |\
	awk -vb=$bsize '$3=="map/'$part'" {printf "%d", $9/b}')
    printf 'echo STAGE %s: WRITING BLOCKS %s-%s\n' \
	$stage $(($skip+$off)) $(($skip+$blocks+$off-1))
    printf 'dd if=/%s of=/dev/map/%s ibs=%s obs=%s conv=osync count=%s %s\n' \
	"$image" "$part" $bsize $bsize $blocks $iseek
    skip=$(($skip+$blocks))
    iseek="iseek=$skip"
    stage=$(($stage+1))
  done
} > bin/flashit
chmod +x bin/flashit

echo Downloading $url
fetch -vo $image $url
kenv vfs.root.mountfrom=ufs:$md
echo Closing network connections and unmounting flash...
reboot -r