Split common.sh into bash-only and dash-only sections

scripts/image_signing/common.sh

Index: scripts/image_signing/common.sh
diff --git a/scripts/image_signing/common.sh b/scripts/image_signing/common.sh
index 98229b01b08f34038d27125dbd94e0d6705570fb..599c9e1e239c5814b75f63c460611fe5301e4f2c 100755
--- a/scripts/image_signing/common.sh
+++ b/scripts/image_signing/common.sh
@@ -1,23 +1,10 @@
 #!/bin/bash
-
-# Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+#
+# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-# Globals
-# ----------------------------------------------------------------------------
-
-# Determine script directory
-SCRIPT_DIR=$(dirname $0)
-PROG=$(basename $0)
-GPT=cgpt
-
-# The tag when the rootfs is changed.
-TAG_NEEDS_TO_BE_SIGNED="/root/.need_to_be_signed"
-
-# List of Temporary files and mount points.
-TEMP_FILE_LIST=$(mktemp)
-TEMP_DIR_LIST=$(mktemp)
+. "$(dirname "$0")/common_minimal.sh"
 
 # Array of actions that are executed during the clean up process.
 declare -a cleanup_actions
@@ -88,278 +75,7 @@ die() {
   exit 1
 }
 
-# Finds and loads the 'shflags' library, or return as failed.
-load_shflags() {
-  # Load shflags
-  if [ -f /usr/lib/shflags ]; then
-    . /usr/lib/shflags
-  elif [ -f "${SCRIPT_DIR}/shflags" ]; then
-    . "${SCRIPT_DIR}/shflags"
-  elif [ -f "${SCRIPT_DIR}/lib/shflags/shflags" ]; then
-    . "${SCRIPT_DIR}/lib/shflags/shflags"
-  else
-    echo "ERROR: Cannot find the required shflags library."
-    return 1
-  fi
-
-  # Add debug option for debug output below
-  DEFINE_boolean debug $FLAGS_FALSE "Provide debug messages" "d"
-}
-
-# Functions for debug output
-# ----------------------------------------------------------------------------
-
-# Reports error message and exit(1)
-# Args: error message
-err_die() {
-  echo "ERROR: $*" 1>&2
-  exit 1
-}
-
-# Returns true if we're running in debug mode.
-#
-# Note that if you don't set up shflags by calling load_shflags(), you
-# must set $FLAGS_debug and $FLAGS_TRUE yourself.  The default
-# behavior is that debug will be off if you define neither $FLAGS_TRUE
-# nor $FLAGS_debug.
-is_debug_mode() {
-  [ "${FLAGS_debug:-not$FLAGS_TRUE}" = "$FLAGS_TRUE" ]
-}
-
-# Prints messages (in parameters) in debug mode
-# Args: debug message
-debug_msg() {
-  if is_debug_mode; then
-    echo "DEBUG: $*" 1>&2
-  fi
-}
-
-# Functions for temporary files and directories
-# ----------------------------------------------------------------------------
-
-# Create a new temporary file and return its name.
-# File is automatically cleaned when cleanup_temps_and_mounts() is called.
-make_temp_file() {
-  local tempfile=$(mktemp)
-  echo "$tempfile" >> $TEMP_FILE_LIST
-  echo $tempfile
-}
-
-# Create a new temporary directory and return its name.
-# Directory is automatically deleted and any filesystem mounted on it unmounted
-# when cleanup_temps_and_mounts() is called.
-make_temp_dir() {
-  local tempdir=$(mktemp -d)
-  echo "$tempdir" >> $TEMP_DIR_LIST
-  echo $tempdir
-}
-
-cleanup_temps_and_mounts() {
-  for i in $(cat $TEMP_FILE_LIST); do
-    rm -f $i
-  done
-  set +e  # umount may fail for unmounted directories
-  for i in $(cat $TEMP_DIR_LIST); do
-    if [ -n "$i" ]; then
-      if has_needs_to_be_resigned_tag "$i"; then
-        echo "Warning: image may be modified. Please resign image."
-      fi
-      sudo umount -d $i 2>/dev/null
-      rm -rf $i
-    fi
-  done
-  set -e
-  rm -rf $TEMP_DIR_LIST $TEMP_FILE_LIST
-}
-
-trap "cleanup_temps_and_mounts" EXIT
-
-# Functions for partition management
-# ----------------------------------------------------------------------------
-
-# Read GPT table to find the starting location of a specific partition.
-# Args: DEVICE PARTNUM
-# Returns: offset (in sectors) of partition PARTNUM
-partoffset() {
-  sudo $GPT show -b -i $2 $1
-}
-
-# Read GPT table to find the size of a specific partition.
-# Args: DEVICE PARTNUM
-# Returns: size (in sectors) of partition PARTNUM
-partsize() {
-  sudo $GPT show -s -i $2 $1
-}
-
-# Tags a file system as "needs to be resigned".
-# Args: MOUNTDIRECTORY
-tag_as_needs_to_be_resigned() {
-  local mount_dir="$1"
-  sudo touch "$mount_dir/$TAG_NEEDS_TO_BE_SIGNED"
-}
-
-# Determines if the target file system has the tag for resign
-# Args: MOUNTDIRECTORY
-# Returns: true if the tag is there otherwise false
-has_needs_to_be_resigned_tag() {
-  local mount_dir="$1"
-  [ -f "$mount_dir/$TAG_NEEDS_TO_BE_SIGNED" ]
-}
-
-# Determines if the target file system is a Chrome OS root fs
-# Args: MOUNTDIRECTORY
-# Returns: true if MOUNTDIRECTORY looks like root fs, otherwise false
-is_rootfs_partition() {
-  local mount_dir="$1"
-  [ -f "$mount_dir/$(dirname "$TAG_NEEDS_TO_BE_SIGNED")" ]
-}
-
-# Mount a partition read-only from an image into a local directory
-# Args: IMAGE PARTNUM MOUNTDIRECTORY
-mount_image_partition_ro() {
-  local image=$1
-  local partnum=$2
-  local mount_dir=$3
-  local offset=$(partoffset "$image" "$partnum")
-  sudo mount -o loop,ro,offset=$((offset * 512)) "$image" "$mount_dir"
-}
-
-# Mount a partition from an image into a local directory
-# Args: IMAGE PARTNUM MOUNTDIRECTORY
-mount_image_partition() {
-  local image=$1
-  local partnum=$2
-  local mount_dir=$3
-  local offset=$(partoffset "$image" "$partnum")
-  # Forcibly call enable_rw_mount.  It should fail on unsupported filesystems
-  # and be idempotent on ext*.
-  enable_rw_mount "$image" $((offset * 512)) 2> /dev/null
-  sudo mount -o loop,offset=$((offset * 512)) "$image" "$mount_dir"
-  if is_rootfs_partition "$mount_dir"; then
-    tag_as_needs_to_be_resigned "$mount_dir"
-  fi
-}
-
-# Extract a partition to a file
-# Args: IMAGE PARTNUM OUTPUTFILE
-extract_image_partition() {
-  local image=$1
-  local partnum=$2
-  local output_file=$3
-  local offset=$(partoffset "$image" "$partnum")
-  local size=$(partsize "$image" "$partnum")
-  dd if=$image of=$output_file bs=512 skip=$offset count=$size conv=notrunc >/dev/null 2>&1
-}
-
-# Replace a partition in an image from file
-# Args: IMAGE PARTNUM INPUTFILE
-replace_image_partition() {
-  local image=$1
-  local partnum=$2
-  local input_file=$3
-  local offset=$(partoffset "$image" "$partnum")
-  local size=$(partsize "$image" "$partnum")
-  dd if=$input_file of=$image bs=512 seek=$offset count=$size conv=notrunc
-}
-
-# For details, see crosutils.git/common.sh
-enable_rw_mount() {
-  local rootfs="$1"
-  local offset="${2-0}"
-
-  # Make sure we're checking an ext2 image
-  if ! is_ext2 "$rootfs" $offset; then
-    echo "enable_rw_mount called on non-ext2 filesystem: $rootfs $offset" 1>&2
-    return 1
-  fi
-
-  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
-  # Dash can't do echo -ne, but it can do printf "\NNN"
-  # We could use /dev/zero here, but this matches what would be
-  # needed for disable_rw_mount (printf '\377').
-  printf '\000' |
-    sudo dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
-            conv=notrunc count=1 bs=1
-}
-
-# For details, see crosutils.git/common.sh
-is_ext2() {
-  local rootfs="$1"
-  local offset="${2-0}"
-
-  # Make sure we're checking an ext2 image
-  local sb_magic_offset=$((0x438))
-  local sb_value=$(sudo dd if="$rootfs" skip=$((offset + sb_magic_offset)) \
-                   count=2 bs=1 2>/dev/null)
-  local expected_sb_value=$(printf '\123\357')
-  if [ "$sb_value" = "$expected_sb_value" ]; then
-    return 0
-  fi
-  return 1
-}
-
-disable_rw_mount() {
-  local rootfs="$1"
-  local offset="${2-0}"
-
-  # Make sure we're checking an ext2 image
-  if ! is_ext2 "$rootfs" $offset; then
-    echo "disable_rw_mount called on non-ext2 filesystem: $rootfs $offset" 1>&2
-    return 1
-  fi
-
-  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
-  # Dash can't do echo -ne, but it can do printf "\NNN"
-  # We could use /dev/zero here, but this matches what would be
-  # needed for disable_rw_mount (printf '\377').
-  printf '\377' |
-    sudo dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
-            conv=notrunc count=1 bs=1
-}
-
-rw_mount_disabled() {
-  local rootfs="$1"
-  local offset="${2-0}"
-
-  # Make sure we're checking an ext2 image
-  if ! is_ext2 "$rootfs" $offset; then
-    return 2
-  fi
-
-  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
-  local ro_value=$(sudo dd if="$rootfs" skip=$((offset + ro_compat_offset)) \
-                   count=1 bs=1 2>/dev/null)
-  local expected_ro_value=$(printf '\377')
-  if [ "$ro_value" = "$expected_ro_value" ]; then
-    return 0
-  fi
-  return 1
-}
-
-# Misc functions
-# ----------------------------------------------------------------------------
-
-# Returns true if all files in parameters exist.
-# Args: List of files
-ensure_files_exist() {
-  local filename return_value=0
-  for filename in "$@"; do
-    if [ ! -f "$filename" -a ! -b "$filename" ]; then
-      echo "ERROR: Cannot find required file: $filename"
-      return_value=1
-    fi
-  done
-
-  return $return_value
-}
-
-# Check if the 'chronos' user already has a password
-# Args: rootfs
-no_chronos_password() {
-  local rootfs=$1
-  sudo grep -q '^chronos:\*:' "$rootfs/etc/shadow"
-}
-
+# This will override the trap set in common_minmal.sh
 trap "cleanup" INT TERM EXIT
 
 add_cleanup_action "cleanup_temps_and_mounts"