#!/bin/bash

# Copyright (c) 2012 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.

SCRIPT_ROOT=$(dirname $(readlink -f "$0"))
. "${SCRIPT_ROOT}/build_library/build_common.sh" || exit 1


# Developer-visible flags.
DEFINE_string board "${DEFAULT_BOARD}" \
  "The board to build an image for."
DEFINE_string boot_args "noinitrd" \
  "Additional boot arguments to pass to the commandline"
DEFINE_boolean enable_rootfs_verification ${FLAGS_TRUE} \
  "Default all bootloaders to use kernel-based root fs integrity checking."
DEFINE_string output_root "${DEFAULT_BUILD_ROOT}/images" \
  "Directory in which to place image result directories (named by version)"
DEFINE_integer rootfs_hash_pad 8 \
  "MiBs reserved at the end of the rootfs image. \
 ceil(0.01 * rootfs_size) is a good minimum."
DEFINE_integer rootfs_partition_size 1024 \
  "rootfs partition size in MiBs."
DEFINE_integer rootfs_size 850 \
  "rootfs filesystem size in MiBs."
DEFINE_integer rootfs_boost_size 0 \
  "MiBs by which to increase the rootfs allocations."
DEFINE_boolean standard_backdoor ${FLAGS_TRUE} \
  "Install standard backdoor credentials for testing"
DEFINE_integer statefulfs_size 1024 \
  "stateful filesystem size in MiBs."
DEFINE_string usb_disk /dev/sdb3 \
  "Path syslinux should use to do a usb boot. Default: /dev/sdb3"

FLAGS_HELP="USAGE: build_image [flags] [list of images to build].
This script is used to build a Chromium OS image. Chromium OS comes in many
different forms.  This scripts can be used to build the following:

base - Pristine Chromium OS image. As similar to Chrome OS as possible.
dev - Developer image. Like base but with additional developer packages.
test - Like dev, but with additional test specific packages and can be easily
  used for automated testing using scripts like run_remote_tests, etc.
factory_test - Like test but with extra packages and modifications used to
  test images in a factory setting.  Cannot be built along with a test image.
factory_install - Install shim for bootstrapping the factory test process.
  Cannot be built along with any other image.

Examples:

build_image --board=<board> dev test - builds developer and test images.
build_image --board=<board> factory_install - builds a factory install shim.
...
"
show_help_if_requested "$@"

# The following options are advanced options, only available to those willing
# to read the source code. They are not shown in help output, since they are
# not needed for the typical developer workflow.
DEFINE_integer build_attempt 1 \
  "The build attempt for this image build."
DEFINE_boolean hybrid_mbr ${FLAGS_FALSE} \
  "Creates a hybrid MBR rather than a protective one"
DEFINE_integer jobs -1 \
  "How many packages to build in parallel at maximum."
DEFINE_boolean replace ${FLAGS_FALSE} \
  "Overwrite existing output, if any."
DEFINE_string symlink "latest" \
  "Symlink name to use for this image."
DEFINE_integer verity_error_behavior 3 \
  "Kernel verified boot error behavior (0: I/O errors, 1: panic, 2: nothing, \
3: cros) Default: 3"
DEFINE_integer verity_max_ios -1 \
  "Number of outstanding I/O operations dm-verity caps at. Default: -1"
DEFINE_string verity_algorithm "sha1" \
  "Cryptographic hash algorithm used for kernel vboot. Default : sha1"
DEFINE_string verity_salt "" \
  "Root filesystem salt. Default: randomly generated."
DEFINE_string version "" \
  "Overrides version number in name to this version."

# 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 'switch_to_strict_mode' is specified before now.
switch_to_strict_mode

# Determine build version.
OVERLAY_CHROMEOS_DIR="${SRC_ROOT}/third_party/chromiumos-overlay/chromeos"
. "${OVERLAY_CHROMEOS_DIR}/config/chromeos_version.sh" || exit 1
# N.B.  Ordering matters for some of the libraries below, because
# some of the files contain initialization used by later files.
. "${BUILD_LIBRARY_DIR}/board_options.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/build_gpt.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/mount_gpt_util.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/build_image_util.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/base_image_util.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/dev_image_util.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/test_image_util.sh" || exit 1
. "${BUILD_LIBRARY_DIR}/test_image_content.sh" || exit 1

parse_build_image_args

# Tweak sizes defaulted or given based on any boost given (or defaulted).
# This is syntactic sugar to separate concerns in callers, and unify
# default values here.
if [[ $FLAGS_rootfs_boost_size -gt 0 ]]; then
  max() {
    echo $(( $1 > $2 ? $1 : $2 ))
  }
  root_boost() {
    echo $(( $1 + ( $1 * $FLAGS_rootfs_boost_size + $FLAGS_rootfs_size - 1 ) \
        / $FLAGS_rootfs_size ))
  }
  FLAGS_rootfs_hash_pad=$(root_boost $FLAGS_rootfs_hash_pad)
  FLAGS_rootfs_partition_size=$(root_boost $FLAGS_rootfs_partition_size)
  FLAGS_rootfs_size=$(root_boost $FLAGS_rootfs_size)
  FLAGS_rootfs_boost_size=0
  # Push up to the recommended minimum if we did not get there.
  FLAGS_rootfs_hash_pad=$(max $FLAGS_rootfs_hash_pad \
      $(( ( $FLAGS_rootfs_size + 99 ) / 100 )))
fi

# Tweak flags, configure extra USE flags, and add packages for the factory
# install shim.
EXTRA_PACKAGES=""
if should_build_image ${CHROMEOS_FACTORY_INSTALL_SHIM_NAME}; then
  # TODO: Build a separated ebuild for the install shim to reduce size.
  INSTALL_MASK="${FACTORY_SHIM_INSTALL_MASK}"

  # Reduce the size of factory install shim.
  info "Fixing the rootfs size at 320 MiB for install shim"
  FLAGS_rootfs_size=300
  FLAGS_rootfs_partition_size=320
  info "Fixing the statefulfs size at 140 MiB for install shim"
  FLAGS_statefulfs_size=140

  # Add the cros_factory_install boot arg.
  FLAGS_boot_args="${FLAGS_boot_args} cros_factory_install"

  # Factory install needs to have the factory installer added.
  EXTRA_PACKAGES="${EXTRA_PACKAGES} chromeos-base/chromeos-factoryinstall"
  # On x86/amd64, we boot the factory install shim from an SD card using
  # initramfs for our root.  On ARM, we boot the factory install shim over the
  # network, so we don't require initramfs, but we do require fbconsole to fix
  # a display driver bug.
  if [ "${ARCH}" = "x86" -o "${ARCH}" = "amd64" ] ; then
    export USE="${USE} initramfs vfat"
  fi
  # CONFIG_BLK_DEV_RAM is disabled by default.
  # But tftp install needs it to mount rootfs in ram
  if [ "${ARCH}" = "arm" ] ; then
    export USE="${USE} fbconsole blkdevram"
  fi
fi

if [ $((FLAGS_rootfs_size + FLAGS_rootfs_hash_pad)) -gt \
     ${FLAGS_rootfs_partition_size} ] ; then
  die_notrace "rootfs ($((FLAGS_rootfs_size + FLAGS_rootfs_hash_pad)) MiB) is" \
    "bigger than partition (${FLAGS_rootfs_partition_size} MiB)."
fi

# If we are creating a developer image, also create a pristine image with a
# different name.
PRISTINE_IMAGE_NAME=
if should_build_image ${CHROMEOS_FACTORY_INSTALL_SHIM_NAME}; then
  PRISTINE_IMAGE_NAME=${CHROMEOS_FACTORY_INSTALL_SHIM_NAME}
else
  PRISTINE_IMAGE_NAME=${CHROMEOS_BASE_IMAGE_NAME}
fi

ROOT_FS_DIR="${BUILD_DIR}/rootfs"
STATEFUL_FS_DIR="${BUILD_DIR}/stateful_partition"
ESP_FS_DIR=${BUILD_DIR}/esp

DEVKEYSDIR="/usr/share/vboot/devkeys"

# ${DEV_IMAGE_ROOT} specifies the location of where developer packages will
# be installed on the stateful dir.  On a Chromium OS system, this will
# translate to /usr/local.
DEV_IMAGE_ROOT="${STATEFUL_FS_DIR}/dev_image"

eclean-$BOARD -d packages

check_blacklist

# Check that the build root is sane.
"${BUILD_LIBRARY_DIR}/test_build_root" --root="${BOARD_ROOT}"

# Hack to fix bug where x86_64 CHOST line gets incorrectly added.
# ToDo(msb): remove this hack.
PACKAGES_FILE="${BOARD_ROOT}/packages/Packages"
sudo sed -e "s/CHOST: x86_64-pc-linux-gnu//" -i "${PACKAGES_FILE}"

# Handle existing directory.
if [[ -e "${BUILD_DIR}" ]]; then
  if [[ ${FLAGS_replace} -eq ${FLAGS_TRUE} ]]; then
    sudo rm -rf "${BUILD_DIR}"
  else
    error "Directory ${BUILD_DIR} already exists."
    error "Use --build_attempt option to specify an unused attempt."
    error "Or use --replace if you want to overwrite this directory."
    die "Unwilling to overwrite ${BUILD_DIR}."
  fi
fi

# Create the output directory and temporary mount points.
mkdir -p "${BUILD_DIR}"
mkdir -p "${ROOT_FS_DIR}" "${STATEFUL_FS_DIR}" "${ESP_FS_DIR}"

# Create the boot.desc file which stores the build-time configuration
# information needed for making the image bootable after creation with
# cros_make_image_bootable.
create_boot_desc

create_base_image ${PRISTINE_IMAGE_NAME}


BOOT_FLAG=
if should_build_image ${CHROMEOS_FACTORY_INSTALL_SHIM_NAME}; then
  BOOT_FLAG="-b 1"  # BOOT_FLAG_DEVELOPER value defined in load_kernel_fw.h
  info "--factory_install set, pass BOOT_FLAG_DEVELOPER flag to" \
    "load_kernel_test"
fi

# Verify pristine image if we built it.
if should_build_image "${PRISTINE_IMAGE_NAME}"; then
  load_kernel_test "${BUILD_DIR}/${PRISTINE_IMAGE_NAME}" \
    "${DEVKEYSDIR}/recovery_key.vbpubk" ${BOOT_FLAG}
fi

# Create a developer image if an image that is based on it is requested.
if should_build_image ${CHROMEOS_DEVELOPER_IMAGE_NAME} \
    ${CHROMEOS_TEST_IMAGE_NAME} ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}; then
  copy_image ${CHROMEOS_BASE_IMAGE_NAME} ${CHROMEOS_DEVELOPER_IMAGE_NAME}
  install_dev_packages ${CHROMEOS_DEVELOPER_IMAGE_NAME}
fi

# From a developer image create a test|factory_test image.
if should_build_image ${CHROMEOS_TEST_IMAGE_NAME}; then
  copy_image  ${CHROMEOS_DEVELOPER_IMAGE_NAME} ${CHROMEOS_TEST_IMAGE_NAME}
  mod_image_for_test  ${CHROMEOS_TEST_IMAGE_NAME}
fi
if should_build_image ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}; then
  copy_image  ${CHROMEOS_DEVELOPER_IMAGE_NAME} \
    ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}
  mod_image_for_test  ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}
fi

rmdir "${ROOT_FS_DIR}" "${STATEFUL_FS_DIR}" "${ESP_FS_DIR}"

# Generating AU generator zip file to run outside chroot
generate_au_zip || echo "Failed generating AU zip file - ignoring Error..."

# Create a named symlink.
LINK_NAME="${FLAGS_output_root}/${BOARD}/${FLAGS_symlink}"
ln -sfT $(basename ${BUILD_DIR}) ${LINK_NAME}

echo "Done.  Image(s) created in ${BUILD_DIR}"

# Print out the images we generated.
if should_build_image ${CHROMEOS_BASE_IMAGE_NAME}; then
  echo "Non-developer Chromium OS image created as ${PRISTINE_IMAGE_NAME}"
fi
if should_build_image ${CHROMEOS_FACTORY_SHIM_NAME}; then
  echo "Chromium OS Factory install shim created as ${PRISTINE_IMAGE_NAME}"
fi
if should_build_image ${CHROMEOS_DEVELOPER_IMAGE_NAME}; then
  echo "Developer image created as ${CHROMEOS_DEVELOPER_IMAGE_NAME}"
fi
if should_build_image ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}; then
  echo "Factory test image created as ${CHROMEOS_FACTORY_TEST_IMAGE_NAME}"
fi
if should_build_image ${CHROMEOS_TEST_IMAGE_NAME}; then
  echo "Test image created as ${CHROMEOS_TEST_IMAGE_NAME}"
fi

print_time_elapsed

cat << EOF
To copy the image to a USB key, use:
  ./image_to_usb.sh --from=${OUTSIDE_OUTPUT_DIR}
To convert it to a VMWare image, use:
  ./image_to_vm.sh --from=${OUTSIDE_OUTPUT_DIR} --board=${BOARD}
EOF