Add a --to option to build_image

src/scripts/build_image

 #!/bin/bash
 
 # Copyright (c) 2009 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 build a bootable keyfob-based chromeos system image from within
 # a chromiumos setup. This assumes that all needed packages have been built into
 # the given target's root with binary packages turned on. This script will
 # build the Chrome OS image using only pre-built binary packages.
@@ skipping 19 matching lines @@
 DEFINE_boolean replace $FLAGS_FALSE \
   "Overwrite existing output, if any."
 DEFINE_boolean withdev $FLAGS_TRUE \
   "Include useful developer friendly utilities in the image."
 DEFINE_boolean installmask $FLAGS_TRUE \
   "Use INSTALL_MASK to shrink the resulting image."
 DEFINE_integer jobs -1 \
   "How many packages to build in parallel at maximum."
 DEFINE_boolean statefuldev $FLAGS_FALSE \
   "Install development packages on stateful partition -- still experimental"
+DEFINE_string to "" \
+  "The target image file or device"
 DEFINE_boolean withtest $FLAGS_FALSE \
   "Include packages required for testing and prepare image for testing"
 
 # Parse command line.
 FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 
 # Only now can we die on error.  shflags functions leak non-zero error codes,
 # so will die prematurely if 'set -e' is specified before now.
 set -e
@@ skipping 12 matching lines @@
 
 # Determine build version.
 . "${SCRIPTS_DIR}/chromeos_version.sh"
 
 # Use canonical path since some tools (e.g. mount) do not like symlinks.
 # Append build attempt to output directory.
 IMAGE_SUBDIR="${CHROMEOS_VERSION_STRING}-a${FLAGS_build_attempt}"
 OUTPUT_DIR="${FLAGS_output_root}/${FLAGS_board}/${IMAGE_SUBDIR}"
 ROOT_FS_DIR="${OUTPUT_DIR}/rootfs"
 ROOT_FS_IMG="${OUTPUT_DIR}/rootfs.image"
-OUTPUT_IMG="${OUTPUT_DIR}/chromiumos_image.bin"
+OUTPUT_IMG=${FLAGS_to:-${OUTPUT_DIR}/chromiumos_image.bin}
 
 BOARD="${FLAGS_board}"
 BOARD_ROOT="${FLAGS_build_root}/${BOARD}"
 
 LOOP_DEV=
 
 # What cross-build are we targeting?
 . "${BOARD_ROOT}/etc/make.conf.board_setup"
 LIBC_VERSION=${LIBC_VERSION:-"2.10.1-r1"}
 
@@ skipping 279 matching lines @@
 
 OUTSIDE_OUTPUT_DIR="../build/images/${FLAGS_board}/${IMAGE_SUBDIR}"
 echo "Done.  Image created in ${OUTPUT_DIR}"
 echo "To copy to USB keyfob, OUTSIDE the chroot, do something like:"
 echo "  ./image_to_usb.sh --from=${OUTSIDE_OUTPUT_DIR} --to=/dev/sdb"
 echo "To convert to VMWare image, OUTSIDE the chroot, do something like:"
 echo "  ./image_to_vmware.sh --from=${OUTSIDE_OUTPUT_DIR}"
 echo "from the scripts directory where you entered the chroot."
 
 trap - EXIT