make_dev_ssd: new script to change SSD image to dev key

scripts/image_signing/common.sh

 #!/bin/bash
 
 # Copyright (c) 2010 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.
 
 # 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"
 
-# Load shflags
-if [ -f /usr/lib/shflags ]; then
-  . /usr/lib/shflags
-else
-  . "${SCRIPT_DIR}/lib/shflags/shflags"
-fi
+# Finds and loads the 'shflags' library, or return as failed.
+load_shflags() {
+  # Load shflags
+  if [ -f /usr/lib/shflags ]; then
+    . /usr/lib/shflags
+  elif [ -f "${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
+}
 
 # List of Temporary files and mount points.
 TEMP_FILE_LIST=$(mktemp)
 TEMP_DIR_LIST=$(mktemp)
 
 # 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: $FLAGS_TRUE if the tag is there, otherwise $FLAGS_FALSE
+# Returns: true if the tag is there otherwise false
 has_needs_to_be_resigned_tag() {
   local mount_dir="$1"
-  if [ -f "$mount_dir/$TAG_NEEDS_TO_BE_SIGNED" ]; then
-    return ${FLAGS_TRUE}
-  else
-    return ${FLAGS_FALSE}
-  fi
+  [ -f "$mount_dir/$TAG_NEEDS_TO_BE_SIGNED" ]
 }
 
 # Determines if the target file system is a Chrome OS root fs
 # Args: MOUNTDIRECTORY
-# Returns: $FLAGS_TRUE if MOUNTDIRECTORY looks like root fs,
-#          otherwise $FLAGS_FALSE
+# Returns: true if MOUNTDIRECTORY looks like root fs, otherwise false
 is_rootfs_partition() {
   local mount_dir="$1"
-  if [ -f "$mount_dir/$(dirname "$TAG_NEEDS_TO_BE_SIGNED")" ]; then
-    return ${FLAGS_TRUE}
-  else
-    return ${FLAGS_FALSE}
-  fi
+  [ -f "$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"
@@ skipping 62 matching lines @@
         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
 }
 
+# Returns true if all files in parameters exist.
+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
+}
+
 trap "cleanup_temps_and_mounts" EXIT