AU: Provide an option for forcing full or delta kernel update.

cros_generate_update_payload

 #!/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.
 
 # Script to generate a Chromium OS update for use by the update engine.
 # If a source .bin is specified, the update is assumed to be a delta update.
 
 # Load common constants.  This should be the first executable line.
@@ skipping 43 matching lines @@
 }
 
 extract_partition_to_temp_file() {
   local filename="$1"
   local partition="$2"
   local temp_file="$3"
   if [ -z "$temp_file" ]; then
     temp_file=$(mktemp /tmp/cros_generate_update_payload.XXXXXX)
     echo "$temp_file"
   fi
-  
+
   local offset=$(partoffset "${filename}" ${partition})  # 512-byte sectors
   local length=$(partsize "${filename}" ${partition})  # 512-byte sectors
   local bs=512
   local sectors_per_two_mib=$((2 * 1024 * 1024 / 512))
   if [ $(( $offset % $sectors_per_two_mib )) -eq 0 -a \
        $(( $length % $sectors_per_two_mib )) -eq 0 ]; then
     bs=$((2 * 1024 * 1024))
     offset=$(($offset / $sectors_per_two_mib))
     length=$(($length / $sectors_per_two_mib))
   else
@@ skipping 17 matching lines @@
   sudo umount "$STATE_MNT"
   STATE_MNT=""
   sudo losetup -d "$STATE_LOOP_DEV"
   STATE_LOOP_DEV=""
 }
 
 extract_kern_root() {
   local bin_file="$1"
   local kern_out="$2"
   local root_out="$3"
-  
+
   if [ -z "$kern_out" ]; then
     die "missing kernel output filename"
   fi
   if [ -z "$root_out" ]; then
     die "missing root output filename"
   fi
-  
+
   extract_partition_to_temp_file "$bin_file" 2 "$kern_out"
   if [ "$FLAGS_patch_kernel" -eq "$FLAGS_TRUE" ]; then
     patch_kernel "$bin_file" "$kern_out"
   fi
   extract_partition_to_temp_file "$bin_file" 3 "$root_out"
 }
 
 DEFINE_string image "" "The image that should be sent to clients."
 DEFINE_string src_image "" "Optional: a source image. If specified, this makes\
  a delta update."
 DEFINE_boolean old_style "$FLAGS_TRUE" "Generate an old-style .gz full update."
 DEFINE_string output "" "Output file"
 DEFINE_boolean patch_kernel "$FLAGS_FALSE" "Whether or not to patch the kernel \
 with the patch from the stateful partition (default: false)"
 DEFINE_string private_key "" "Path to private key in .pem format."
 DEFINE_boolean extract "$FLAGS_FALSE" "If set, extract old/new kernel/rootfs \
 to [old|new]_[kern|root].dat. Useful for debugging (default: false)"
+DEFINE_boolean full_kernel "$FLAGS_FALSE" "Generate a full kernel update even \
+if generating a delta update (default: false)"
 
 # Parse command line
 FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 
 set -e
 
 if [ -n "$FLAGS_src_image" ]; then
   # We need to be in the chroot for generating delta images
   assert_inside_chroot
@@ skipping 27 matching lines @@
 
 if [ "$DELTA" -eq "$FLAGS_TRUE" -o "$FLAGS_old_style" -eq "$FLAGS_FALSE" ]; then
   echo "Generating a delta update"
 
   # Sanity check that the real generator exists:
   GENERATOR="$(dirname "$0")/../platform/update_engine/delta_generator"
   [ -x "$GENERATOR" ] || die "$GENERATOR doesn't exist, or isn't executable"
 
   trap cleanup INT TERM EXIT
   if [ "$DELTA" -eq "$FLAGS_TRUE" ]; then
-    SRC_KERNEL=$(extract_partition_to_temp_file "$FLAGS_src_image" 2)
-    if [ "$FLAGS_patch_kernel" -eq "$FLAGS_TRUE" ]; then
-      patch_kernel "$FLAGS_src_image" "$SRC_KERNEL"
+    if [ "$FLAGS_full_kernel" -eq "$FLAGS_FALSE" ]; then
+      SRC_KERNEL=$(extract_partition_to_temp_file "$FLAGS_src_image" 2)
+      if [ "$FLAGS_patch_kernel" -eq "$FLAGS_TRUE" ]; then
+        patch_kernel "$FLAGS_src_image" "$SRC_KERNEL"
+      fi
+      echo md5sum of src kernel:
+      md5sum "$SRC_KERNEL"
+    else
+      echo "Generating a full kernel update."
     fi
     SRC_ROOT=$(extract_partition_to_temp_file "$FLAGS_src_image" 3)
 
-    echo md5sum of src kernel:
-    md5sum "$SRC_KERNEL"
     echo md5sum of src root:
     md5sum "$SRC_ROOT"
   fi
 
   DST_KERNEL=$(extract_partition_to_temp_file "$FLAGS_image" 2)
   if [ "$FLAGS_patch_kernel" -eq "$FLAGS_TRUE" ]; then
     patch_kernel "$FLAGS_image" "$DST_KERNEL"
   fi
   DST_ROOT=$(extract_partition_to_temp_file "$FLAGS_image" 3)
 
   if [ "$DELTA" -eq "$FLAGS_TRUE" ]; then
     SRC_MNT=$(mktemp -d /tmp/src_root.XXXXXX)
     sudo mount -o loop,ro "$SRC_ROOT" "$SRC_MNT"
 
     DST_MNT=$(mktemp -d /tmp/src_root.XXXXXX)
     sudo mount -o loop,ro "$DST_ROOT" "$DST_MNT"
 
     sudo "$GENERATOR" \
         -new_dir "$DST_MNT" -new_image "$DST_ROOT" -new_kernel "$DST_KERNEL" \
         -old_dir "$SRC_MNT" -old_image "$SRC_ROOT" -old_kernel "$SRC_KERNEL" \
         -out_file "$FLAGS_output" -private_key "$FLAGS_private_key"
   else
     "$GENERATOR" \
         -new_image "$DST_ROOT" -new_kernel "$DST_KERNEL" \
         -out_file "$FLAGS_output" -private_key "$FLAGS_private_key"
   fi
 
   trap - INT TERM EXIT
   cleanup noexit
-  
+
   if [ "$DELTA" -eq "$FLAGS_TRUE" ]; then
     echo "Done generating delta."
   else
     echo "Done generating new style full update."
   fi
 else
   echo "Generating full update"
 
   trap cleanup INT TERM EXIT
   DST_KERNEL=$(extract_partition_to_temp_file "$FLAGS_image" 2)
   if [ "$FLAGS_patch_kernel" -eq "$FLAGS_TRUE" ]; then
     patch_kernel "$FLAGS_image" "$DST_KERNEL"
   fi
   DST_ROOT=$(extract_partition_to_temp_file "$FLAGS_image" 3)
 
   GENERATOR="$(dirname "$0")/mk_memento_images.sh"
 
   CROS_GENERATE_UPDATE_PAYLOAD_CALLED=1 "$GENERATOR" "$DST_KERNEL" "$DST_ROOT"
   mv "$(dirname "$DST_KERNEL")/update.gz" "$FLAGS_output"
 
   trap - INT TERM EXIT
   cleanup noexit
   echo "Done generating full update."
 fi