[PATCH 2/2] Support persistent device naming symlinks, UUID, and LABEL tags

[Milan Kupcevic]

Support persistent device naming symlinks, UUID, and LABEL tags
in addition to openfirmware paths and aliases as traditional Unix
block device names are not persistent anymore.

Signed-off-by: Milan Kupcevic <milan at physics.harvard.edu>
---
 ybin/yabootconfig |   27 ++++++++++++++++++++++++---
 ybin/ybin         |    6 ++++++
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/ybin/yabootconfig b/ybin/yabootconfig
index 04a513c..4629e10 100755
--- a/ybin/yabootconfig
+++ b/ybin/yabootconfig
@@ -27,7 +27,7 @@ if [ -n "$PATH_PREFIX" ] ; then
     PATH="${PATH}:${PATH_PREFIX}/sbin:${PATH_PREFIX}/bin:${PATH_PREFIX}/usr/sbin:${PATH_PREFIX}/usr/bin:${PATH_PREFIX}/usr/local/sbin:${PATH_PREFIX}/usr/local/bin"
 fi
 PRG="${0##*/}"
-VERSION=1.0.8
+VERSION=1.0.8+debian2
 CHROOT=/
 ## $CONFIG is relative to $CHROOT
 CONFIG=etc/yaboot.conf
@@ -732,6 +732,27 @@ if [ -n "$INITRDIMG" ] ; then
     INITRDIMGS="\tinitrd=$INITRDIMG\n\tinitrd-size=8192\n"
 fi
 
+## Get a symlink which always points to the correct block device.
+## If it does not exist, give the unix block device name back.
+devsymlink() {
+  [ "$2" != "nobyid" ] && BYID="/dev/disk/by-id/scsi* /dev/disk/by-id/*"
+  for SYMLINK in $BYID /dev/disk/by-uuid/* /dev/disk/by-label/*; do
+    [ "`readlink -f "$SYMLINK"`" = "$1" ] && {
+      echo $SYMLINK
+      return
+    }
+  done
+  echo $1
+}
+
+## Get UUID= or LABEL= for the given unix partition block device.
+## If it could not be determined, give the unix partition block device back.
+uuidlabel() {
+  echo `devsymlink "$1" nobyid` \
+  | sed -e "s,/dev/disk/by-uuid/,UUID=," \
+        -e "s,/dev/disk/by-label/,LABEL=,"
+}
+
 ## generate global section of yaboot.conf
 GLOBAL="## yaboot.conf generated by $PRG $VERSION
 ##
@@ -739,9 +760,9 @@ GLOBAL="## yaboot.conf generated by $PRG $VERSION
 ${HEADER}##
 ## For a dual-boot menu, add one or more of:
 ## bsd=/dev/hdaX, macos=/dev/hdaY, macosx=/dev/hdaZ\n
-boot=${BOOT}${DEVICE:-}
+boot=\"`devsymlink "${BOOT}"`\"${DEVICE:-}
 partition=$PARTITION
-root=$ROOT
+root=\"`uuidlabel "${ROOT}"`\"
 timeout=30
 install=${INSTALL}${OFBOOT:-}\n"
 
diff --git a/ybin/ybin b/ybin/ybin
index 44e63f4..cbc14f4 100755
--- a/ybin/ybin
+++ b/ybin/ybin
@@ -1641,6 +1641,12 @@ if [ "$boot" = unconfigured ] ; then
     exit 1
 fi
 
+## also accept quoted symlink names
+for v in boot bsd macos macosx darwin ; do
+  eval $v="\`echo \$$v | tr -d '\"'\`"
+  eval [ -h \"\$$v\" ] \&\& $v="\`readlink -f \$$v\`"
+done
+
 ## if there is still no config file use the automatic generation to make a
 ## generic yaboot.conf. do this before the confcheck to avoid wierd errors.
 if [ "$bootconf" = /dev/null ] ; then
-- 
1.7.2.5