From 9b7cb51697bddf086fd6a697b5280be20ed2e1dc Mon Sep 17 00:00:00 2001
From: Will Drewry <wad@chromium.org>
Date: Wed, 20 Oct 2010 18:11:24 -0500
Subject: [PATCH] common.sh: switch out echo -ne for printf and fix incorrect
 offset

echo -ne isn't portable but printf with octals is so this
makes the switch.

In addition, the current offset is off by 3 and is updating the UUID space.
This was from style cleanup and all functional test passed - of course.
This change fixes that too.

TEST=built and installed and checked ro enforcement works
BUG=chromium-os:7972

Change-Id: Ifb3cb2c6f3219af819baff5750453439e1ba6edf

Review URL: http://codereview.chromium.org/3997001
---
 common.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/common.sh b/common.sh
index 24862aa407..9a9699ede7 100644
--- a/common.sh
+++ b/common.sh
@@ -475,8 +475,8 @@ setup_symlinks_on_root() {
 disable_rw_mount() {
   local rootfs="$1"
   local offset="${2-0}"  # in bytes
-  local ro_compat_offset=$((0x467 + 3))  # Set 'highest' byte
-  echo -ne '\xff' |
+  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
+  printf '\377' |
     sudo dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
             conv=notrunc count=1 bs=1
 }
@@ -484,8 +484,8 @@ disable_rw_mount() {
 enable_rw_mount() {
   local rootfs="$1"
   local offset="${2-0}"
-  local ro_compat_offset=$((0x467 + 3))  # Set 'highest' byte
-  echo -ne '\x00' |
+  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
+  printf '\000' |
     sudo dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
             conv=notrunc count=1 bs=1
 }