#!/bin/bash

# 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.

. "$(dirname "$0")/common.sh" || exit 1
. "${SRC_ROOT}/platform/dev/toolchain_utils.sh"

# Script must run inside the chroot
restart_in_chroot_if_needed "$@"

get_default_board

# Developer-visible flags.
DEFINE_string board "$DEFAULT_BOARD" \
  "The name of the board to set up."
DEFINE_boolean default $FLAGS_FALSE \
  "Set board to the default board in your chroot"
DEFINE_boolean force $FLAGS_FALSE \
  "Force re-creating board root."
DEFINE_boolean usepkg $FLAGS_TRUE \
  "Use binary packages to bootstrap."

FLAGS_HELP="usage: $(basename $0) [flags]

setup_board sets up the sysroot for a particular board. This script is called
automatically when you run build_packages, so there is typically no need to
call it directly, unless you want to blow away your board (using --force).
"
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_string board_overlay "" \
  "Location of the board overlay."
DEFINE_string binutils_version "2.21-r4" \
  "Version of binutils to use."
DEFINE_boolean fast ${DEFAULT_FAST} "Call many emerges in parallel"
DEFINE_string gcc_version "[stable]" \
  "Version of gcc to use."
DEFINE_integer jobs -1 \
  "How many packages to build in parallel at maximum."
DEFINE_string kernel_version "[stable]" \
  "Version of kernel headers to use."
DEFINE_boolean latest_toolchain $FLAGS_FALSE \
  "Use the latest ebuild for all toolchain packages (gcc, binutils, libc, \
kernel). This overrides the other toolchain version options."
DEFINE_string libc_version "[stable]" \
  "Version of libc to use."
DEFINE_string profile "" \
  "The portage configuration profile to use. Profile must be located in overlay-board/profiles"
DEFINE_boolean quiet $FLAGS_FALSE \
  "Don't print warnings when board already exists."
DEFINE_boolean skip_toolchain_update $FLAGS_FALSE \
  "Don't update toolchain automatically."
DEFINE_boolean skip_chroot_upgrade $FLAGS_FALSE \
  "Don't run the chroot upgrade automatically; use with care."
DEFINE_string toolchain "" \
  "Toolchain.  For example: i686-pc-linux-gnu, armv7a-softfloat-linux-gnueabi"
DEFINE_string variant "" \
  "Board variant."

# The --reuse_pkgs_from_local_boards flag tells Portage to share binary
# packages between boards that are built locally, so that the total time
# required to build several boards is reduced. This flag is only useful
# when you are not able to use remote binary packages, since remote binary
# packages are usually more up to date than anything you have locally.
DEFINE_boolean reuse_pkgs_from_local_boards $FLAGS_FALSE \
  "Bootstrap from local packages instead of remote packages."


# builds wrappers like equery-arm-generic.
# args:
#   $1:  command to wrap
#   rest:  extra arguments to pass to the command
generate_wrapper() {
  local command="${1}"
  shift
  local extra_args="$@"


  local target="/usr/local/bin/${command}-${BOARD_VARIANT}"
  sudo_clobber "${target}" <<EOF
#!/bin/bash

export CHROMEOS_ROOT="$GCLIENT_ROOT"
export CHOST="$FLAGS_toolchain"
export PORTAGE_CONFIGROOT="$BOARD_ROOT"
export SYSROOT="$BOARD_ROOT"
if [ -z "\$PORTAGE_USERNAME" ]; then
  export PORTAGE_USERNAME=\$(basename \$HOME)
fi
export ROOT="$BOARD_ROOT"
exec sudo -E ${command} ${extra_args} "\$@"
EOF
  sudo chmod +rx ${target}
  sudo chown root:root ${target}
  eval ${command^^}_WRAPPER="${target}" # ${foo^^} returns toupper($foo)
  echo created wrapper ${target}
}

generate_pkgconfig_wrapper() {
  local target="/usr/local/bin/pkg-config-${BOARD_VARIANT}"
  sudo_clobber "${target}" <<EOF
#!/bin/bash

PKG_CONFIG_LIBDIR="${BOARD_ROOT}/usr/lib/pkgconfig:\
${BOARD_ROOT}/usr/lib64/pkgconfig:\
${BOARD_ROOT}/usr/share/pkgconfig"
export PKG_CONFIG_LIBDIR

export PKG_CONFIG_SYSROOT_DIR="${BOARD_ROOT}"

exec pkg-config "\$@"
EOF
  sudo chmod a+rx ${target}
  sudo chown root:root ${target}
  echo created wrapper pkg-config
}

# Checks whether the libc version installed in the board
# matches the one installed by the toolchain.
board_needs_libc_update() {
  local board_version=$(. "${BOARD_SETUP}"; echo "${LIBC_VERSION}")
  local toolchain_version=$(cross_get_version glibc)
  if [[ "${board_version}" = "${toolchain_version}" ]]; then
    return 1
  fi
  return 0
}

# Check whether any new toolchain packages are available.
# Returns true if new toolchain packages are available and false otherwise.
toolchain_needs_update() {
  # Skip toolchain updates if requested.
  if [ $FLAGS_skip_toolchain_update -eq $FLAGS_TRUE ]; then
    return 1
  fi

  local toolchain=$1 crossdev_cfg category arch

  # Query crossdev for how it will be laying things out.
  crossdev_cfg=$(crossdev --show-target-cfg "${toolchain}" --ex-gdb)
  category=$(eval "${crossdev_cfg}"; echo "${category}")
  arch=$(eval "${crossdev_cfg}"; echo "${arch}")

  # If toolchain symlinks weren't created yet, we definitely need to update.
  if [ ! -d ${CROSSDEV_OVERLAY}/${category} ]; then
    # NOTE: In this branch, the versions have not been resolved, and will
    # be passed directly to crossdev. That works because crossdev understands
    # '[stable]'.
    # We cannot resolve the versions because the cross toolchain category is
    # not yet set up.
    return 0
  fi

  # Unmask any ebuilds previously [un]masked by crossdev. crossdev will
  # re-setup its masks appropriately the next time we run it.
  local d
  for d in package.{mask,keywords} ; do
    d="/etc/portage/${d}"
    if [[ -e ${d}/${category} ]] ; then
      sudo mv -f ${d}/{,.bak.}${category}
    fi
  done

  # Now get the atoms out of crossdev for the emerge below.
  local pfx
  if [[ ${FLAGS_latest_toolchain} -eq ${FLAGS_TRUE} ]] ; then
    pfx=""
  elif [[ ${FLAGS_usepkg} -eq ${FLAGS_TRUE} ]] ; then
    pfx="<="
  else
    pfx="="
  fi

  local crosspkgs=$(eval "${crossdev_cfg}"; echo "${crosspkgs}")
  local pkgs=()
  for pkg in ${crosspkgs} ; do
    local pn=$(eval "${crossdev_cfg}" \; echo \${${pkg}_pn})
    local atom="${category}/${pn}"

    if [[ -z ${pn} ]] ; then
      # Not all toolchains provide all packages
      # e.g. arm-elf does not have "kernel" headers.
      continue
    fi

    if [[ ${FLAGS_latest_toolchain} -ne ${FLAGS_TRUE} ]] ; then
      local flagname="FLAGS_${pkg}_version"

      # Some packages (like gdb) don't have pinned versions.
      if [[ -n ${!flagname} ]] ; then
        if [[ ${!flagname} == "[stable]" ]] ; then
          # This will return the full cat/pn-ver for us.
          atom="${pfx}"$(ACCEPT_KEYWORDS="${arch}" \
                         portageq best_visible / ebuild "${atom}")
        else
          atom="${pfx}${atom}-${!flagname}"
        fi
      fi
    fi

    pkgs+=( "${atom}" )
  done

  local flags=( --pretend --quiet --update --nodeps )
  if [[ ${FLAGS_usepkg} -eq ${FLAGS_TRUE} ]] ; then
    flags+=( --getbinpkg --usepkgonly )
  fi

  ACCEPT_KEYWORDS="~* *" emerge "${flags[@]}" "${pkgs[@]}" | grep ${category}/
  local ret=$?

  # Restore the masks in case we don't end up running crossdev.
  for d in package.{mask,keywords} ; do
    d="/etc/portage/${d}"
    if [[ -e ${d}/.bak.${category} ]] ; then
      sudo mv -f ${d}/{.bak.,}${category}
    fi
  done

  return ${ret}
}

uninstall_toolchain() {
  local toolchain=$1
  info "Uninstalling the toolchain."
  # Even if the uninstall fails, keep going. It's likely
  # that it didn't exist in the first place.
  sudo crossdev -v --force -C "${toolchain}" || true
}

# Build the toolchain with crossdev.
build_toolchain() {
  local toolchain=$1
  info "Building the toolchain."
  local CROSS_ARGS=( --show-fail-log --target "${toolchain}" -P --oneshot )
  if [ $FLAGS_usepkg -eq $FLAGS_TRUE ]; then
    # Grab the latest packages from the prebuilt server.
    #  --getbinpkg: Use packages from the prebuilt server.
    #  --usepkgonly: Always use prebuilts. Don't build from source.
    #  --without-headers: Don't build headers-only versions of packages for
    #                     bootstrapping. Because we use binary packages, this
    #                     isn't necessary.
    CROSS_ARGS+=( -P --getbinpkg -P --usepkgonly --without-headers )
  fi
  if [ $FLAGS_latest_toolchain -ne $FLAGS_TRUE ]; then
    CROSS_ARGS+=(
      --binutils $FLAGS_binutils_version
      --gcc $FLAGS_gcc_version
      --kernel $FLAGS_kernel_version
      --libc $FLAGS_libc_version
    )
  fi
  CROSS_ARGS+=(
    --overlays "${CHROMIUMOS_OVERLAY} /usr/local/portage/stable"
    --ov-output "${CROSSDEV_OVERLAY}"
    --ex-gdb
  )

  sudo -E FEATURES="splitdebug ${FEATURES}" crossdev "${CROSS_ARGS[@]}"
}

# Get the version number of a toolchain package.
cross_get_version() {
  local pkg="$1"
  local cpv=""
  if [[ "$CHOST" != "$FLAGS_toolchain" ]]; then
    if [[  "$pkg" = "gcc" ]]; then
      # Users can install multiple versions of gcc at once, so we need to call
      # gcc-config to find out which installed version is selected.
      local path=$(CTARGET=$FLAGS_toolchain gcc-config -B || true)
      cpv=$(portageq owners / $path | sed -e '/^\t/d')
    else
      cpv=$(portageq match / cross-$FLAGS_toolchain/$pkg || true)
    fi
  else
    if [[ "$pkg" = binutils ]] ; then
      cpv=$(portageq match / sys-devel/binutils || true)
    elif [[ "$pkg" = glibc ]] ; then
      cpv=$(portageq match / sys-libs/glibc || true)
    elif [[ "$pkg" = gcc ]] ; then
      cpv=$(portageq match / sys-devel/gcc || true)
    else
      die "Unknown pkg ${pkg}"
    fi
  fi
  local cp=$(echo $cpv | sed -e 's/-r[0-9]*$//; s/-[^-]*$//')
  local result="${cpv#$cp-}"
  local count="$(echo $result | wc -w)"
  if [ "$count" -gt "1" ]; then
    die "Multiple versions of $pkg installed"
  elif [ "$count" -lt "1" ]; then
    die "Cannot find $pkg"
  fi
  echo $result
}

install_toolchain_in_provided() {
  local binutils_ver="$1"
  local gcc_ver="$2"
  local glibc_ver="$3"
  # Tell portage that toolchain packages are already installed in the sysroot.
  (
    echo sys-devel/binutils-$binutils_ver
    echo sys-devel/gcc-$gcc_ver
    echo sys-libs/glibc-$glibc_ver
  ) | sudo_clobber "$BOARD_PROFILE/package.provided"
}

# Install all of the stuff that depends on the toolchain versions
# into the board root.
install_toolchain_in_board() {
  local binutils_ver=$(cross_get_version binutils)
  local gcc_ver=$(cross_get_version gcc)
  local libc_ver=$(cross_get_version glibc)
  if [[ -z "$binutils_ver" || -z "$gcc_ver" || -z "$libc_ver" ]]; then
    die "Cannot find toolchain to install into board root"
  fi
  echo "Installing the toolchain into the board root."
  # Untar glibc to get most of the headers required to build.
  LIBC_TAR="glibc-${libc_ver}.tbz2"

  # Install libc libraries.
  if [ "${CHOST}" != "$FLAGS_toolchain" ] ; then
    LIBC_PATH="${PKGDIR}/cross-${FLAGS_toolchain}/${LIBC_TAR}"
    sudo tar jxpf "${LIBC_PATH}" -C "${BOARD_ROOT}" ./usr/${FLAGS_toolchain} --strip-components=3
    sudo mkdir -p ${BOARD_ROOT}/usr/lib/debug
    sudo tar jxpf "${LIBC_PATH}" -C "${BOARD_ROOT}/usr/lib/debug" ./usr/lib/debug/usr/${FLAGS_toolchain} --strip-components=6 || warn "libc debug info not copied."
    GCC_PKG=cross-${FLAGS_toolchain}/gcc-$gcc_ver

    # TODO(asharif): Remove this hack after a while.
    BOARD_GCC_DIR="${BOARD_ROOT}/usr/lib/gcc"
    if [[ -L "${BOARD_GCC_DIR}" ]] ; then
      sudo rm -f "${BOARD_GCC_DIR}"
    fi
    copy_gcc_libs "${BOARD_ROOT}" "cross-$FLAGS_toolchain/gcc-$gcc_ver"
  else
    sudo mkdir -p ${BOARD_ROOT}/usr/lib64
    sudo ln -sf ${BOARD_ROOT}/usr/lib64 ${BOARD_ROOT}/usr/lib
    sudo mkdir -p ${BOARD_ROOT}/lib64
    sudo ln -sf ${BOARD_ROOT}/lib64 ${BOARD_ROOT}/lib
    LIBC_PATH="${PKGDIR}/sys-libs/${LIBC_TAR}"
    sudo emerge --oneshot --nodeps -k --root=${BOARD_ROOT} =sys-libs/glibc-${libc_ver}
    sudo mkdir -p ${BOARD_ROOT}/usr/lib/debug
    # TODO: we have no debug
    GCC_PKG=sys-devel/gcc-$gcc_ver
  fi

  # Some header files are needed also for rpcbind (NFS support)
  # TODO: Figure out a better way of doing this too?
  sudo cp -a /usr/include/rpcsvc/mount.h "${BOARD_ROOT}/usr/include/rpcsvc"
  sudo cp -a /usr/include/rpcsvc/rquota.h "${BOARD_ROOT}/usr/include/rpcsvc"
  sudo cp -a /usr/include/rpcsvc/nfs_prot.h "${BOARD_ROOT}/usr/include/rpcsvc"
  sudo cp -a /usr/include/rpcsvc/yppasswd.h "${BOARD_ROOT}/usr/include/rpcsvc"

  install_toolchain_in_provided "$binutils_ver" "$gcc_ver" "$libc_ver"

  # Configure new libc version in make.conf.board_setup.
  sudo sed -i -e "/^LIBC_VERSION=/d" $BOARD_SETUP
  echo "LIBC_VERSION=\"$libc_ver\"" | sudo_append $BOARD_SETUP
}

# Print contents of $BOARD_ETC/make.conf.board. This file sources make.conf
# from each overlay, and then calculates the prebuilt URLs based on the
# various binhost configuration files.
print_board_make_conf() {
  echo "# AUTO-GENERATED FILE. DO NOT EDIT."
  echo
  echo "# Source make.conf from each overlay."
  local boto_config=""
  for overlay in $BOARD_OVERLAY_LIST; do
    if [[ -f "$overlay/make.conf" ]]; then
      echo source "$overlay/make.conf"
    fi
    if [[ -f "$overlay/googlestorage_account.boto" ]]; then
      boto_config="$overlay/googlestorage_account.boto"
    fi
  done
  local chromeos_overlay="$SRC_ROOT/private-overlays/chromeos-overlay"
  if [[ -f "$chromeos_overlay/googlestorage_account.boto" ]]; then
    boto_config="$chromeos_overlay/googlestorage_account.boto"
  fi
  local gsutil_cmd='gsutil cp \"${URI}\" \"${DISTDIR}/${FILE}\"'
  echo
  echo FETCHCOMMAND_GS="\"bash -c 'BOTO_CONFIG=$boto_config $gsutil_cmd'\""
  echo RESUMECOMMAND_GS='"$FETCHCOMMAND_GS"'
  echo
}

print_binhost_config() {
  if [ "$1" == "--local" ]; then
    cros_generate_local_binhosts --board "${BOARD_VARIANT}"
    echo 'PORTAGE_BINHOST="$LOCAL_BINHOST"'
    return 0
  elif [ $# -ne 0 ]; then
    die "Invalid arguments for print_binhost_config: $@"
  fi

  local binhost_dir="$CHROMIUMOS_OVERLAY/chromeos/binhost/target"
  local preflight_binhost="$binhost_dir/$BOARD-PREFLIGHT_BINHOST.conf"
  local chrome_binhost_suffix="LATEST_RELEASE_CHROME_BINHOST.conf"
  local chrome_binhost="$binhost_dir/$BOARD-$chrome_binhost_suffix"
  if [[ $ARCH = x86 && ! -f "$preflight_binhost" ]]; then
    preflight_binhost="$binhost_dir/x86-generic-PREFLIGHT_BINHOST.conf"
  elif [[ $ARCH = amd64 && ! -f "$preflight_binhost" ]]; then
    preflight_binhost="$binhost_dir/amd64-generic-PREFLIGHT_BINHOST.conf"
  fi
  if [[ $ARCH = x86 && ! -f "$chrome_binhost" ]]; then
    chrome_binhost="$binhost_dir/x86-generic-$chrome_binhost_suffix"
  elif [[ $ARCH = amd64 && ! -f "$chrome_binhost" ]]; then
    chrome_binhost="$binhost_dir/amd64-generic-$chrome_binhost_suffix"
  fi

  local partner_overlay="$SRC_ROOT/private-overlays/chromeos-partner-overlay"
  local internal_binhost_dir="$partner_overlay/chromeos/binhost/target"
  local internal_binhost="$internal_binhost_dir/$BOARD-PREFLIGHT_BINHOST.conf"

  cat <<'EOF'
# FULL_BINHOST is populated by the full builders. It is listed first because it
# is the lowest priority binhost. It is better to download packages from the
# preflight binhost because they are fresher packages.
PORTAGE_BINHOST="$FULL_BINHOST"

EOF

  if [[ -f "$preflight_binhost" && -z "$IGNORE_PREFLIGHT_BINHOST" ]]; then
    cat <<'EOF'
# PREFLIGHT_BINHOST is populated by the preflight builders. If the same
# package is provided by both the preflight and full binhosts, the package is
# downloaded from the preflight binhost.
EOF
    echo source "$preflight_binhost"
    echo 'PORTAGE_BINHOST="$PORTAGE_BINHOST $PREFLIGHT_BINHOST"'
    echo
  fi

  if [[ -f "$internal_binhost"  && -z "$IGNORE_PREFLIGHT_BINHOST" ]]; then
    cat <<'EOF'
# The internal PREFLIGHT_BINHOST is populated by the internal preflight
# builders. It takes priority over the public preflight binhost.
EOF
    echo source "$internal_binhost"
    echo 'PORTAGE_BINHOST="$PORTAGE_BINHOST $PREFLIGHT_BINHOST"'
    echo
  fi

  if [[ -f "$chrome_binhost" ]]; then
    cat <<'EOF'
# LATEST_RELEASE_CHROME_BINHOST provides prebuilts for chromeos-chrome only.
EOF
    echo source "$chrome_binhost"
    echo 'PORTAGE_BINHOST="$PORTAGE_BINHOST $LATEST_RELEASE_CHROME_BINHOST"'
  fi
}

print_board_binhost_config() {
  if [ "${FLAGS_reuse_pkgs_from_local_boards}" -eq "${FLAGS_TRUE}" ]; then
    print_binhost_config --local
  else
    print_binhost_config
  fi
}

# Parse command line flags
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

if [ -z "$FLAGS_board" ] ; then
  error "--board required."
  exit 1
fi

# Before we can run any tools, we need to update chroot
UPDATE_ARGS=""
if [ "${FLAGS_fast}" -eq "${FLAGS_TRUE}" ]; then
  UPDATE_ARGS+=" --fast"
else
  UPDATE_ARGS+=" --nofast"
fi
if [ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ]; then
  UPDATE_ARGS+=" --usepkg"
else
  UPDATE_ARGS+=" --nousepkg"
fi
if [[ "${FLAGS_jobs}" -ne -1 ]]; then
  UPDATE_ARGS+=" --jobs=${FLAGS_jobs}"
fi
if [ "${FLAGS_skip_chroot_upgrade}" -eq "${FLAGS_FALSE}" ] ; then
  "${SRC_ROOT}/scripts"/update_chroot ${UPDATE_ARGS}
fi

get_board_and_variant $FLAGS_board $FLAGS_variant

#
# Fetch the toolchain from the board overlay.
#
all_toolchains=( $(get_all_board_toolchains "${BOARD}") )
: ${FLAGS_toolchain:=${all_toolchains[0]}}

if [ -z "${FLAGS_toolchain}" ]; then
  error "No toolchain specified in board overlay or on command line."
  exit 1
fi

ARCH=$(get_board_arch "${BOARD}") || exit 1

case "$BOARD" in
  *-host)
    if [[ $FLAGS_usepkg -eq $FLAGS_TRUE ]]; then
      die "host boards only support --nousepkg"
    fi
    HOST_BOARD=true
    ;;
  *)
    HOST_BOARD=false
esac
# Locations we will need
BOARD_ROOT="/build/${BOARD_VARIANT}"
CROSSDEV_OVERLAY="/usr/local/portage/crossdev"
CHROMIUMOS_OVERLAY="/usr/local/portage/chromiumos"
CHROMIUMOS_CONFIG="${CHROMIUMOS_OVERLAY}/chromeos/config"
CHROMIUMOS_PROFILES="${CHROMIUMOS_OVERLAY}/profiles"
BOARD_ETC="${BOARD_ROOT}/etc"
BOARD_SETUP="${BOARD_ETC}/make.conf.board_setup"
BOARD_PROFILE="${BOARD_ETC}/portage/profile"

#
# Construct board overlay list.
#
BOARD_OVERLAY_LIST=$(cros_overlay_list \
  --board "$BOARD" \
  --board_overlay "$FLAGS_board_overlay" \
  --variant "$VARIANT")

eval $(portageq envvar -v CHOST PKGDIR)

# Update all the toolchains that this board wants.
for toolchain in ${all_toolchains[@]} ; do
  [[ "${CHOST}" == "${toolchain}" ]] && continue
  info "Checking for updates to ${toolchain} ..."

  toolchain_updated=${FLAGS_FALSE}
  if toolchain_needs_update ${toolchain} ; then
    toolchain_updated=${FLAGS_TRUE}

    warn "Toolchain needs to be updated! Updating ${toolchain} ..."
    uninstall_toolchain ${toolchain}
    build_toolchain ${toolchain}

    if [[ "${toolchain}" != arm* ]] ; then
      info "Switching on gold as the default linker."
      BINUTILS_VERSION=$(cross_get_version binutils | sed 's/-r[0-9]\+//g')
      sudo binutils-config "${FLAGS_toolchain}-${BINUTILS_VERSION}-gold"
    fi
  fi

  if [[ "${toolchain}" == "${FLAGS_toolchain}" ]] &&
     [ -d "$BOARD_ROOT" ] && [ "$FLAGS_force" == "$FLAGS_FALSE" ] ; then
    if [[ "${toolchain_updated}" == "${FLAGS_TRUE}" ]] ; then
      # If the board root already exists, re-install the toolchain there.
      install_toolchain_in_board
    elif board_needs_libc_update; then
      # Update the users libc in their board if needed.
      echo "Updating libc in the board."
      install_toolchain_in_board
    fi
  fi
done

if [ -d "$BOARD_ROOT" ] ; then
  if [[ $FLAGS_force -eq $FLAGS_TRUE ]]; then
    echo "--force set.  Re-creating $BOARD_ROOT..."
    # Removal takes long. Make it asynchronous.
    TEMP_DIR=`mktemp -d`
    sudo mv $BOARD_ROOT $TEMP_DIR
    sudo rm -rf $TEMP_DIR &
  else
    if ! $HOST_BOARD; then
      { print_board_make_conf; print_board_binhost_config; } | \
        sudo_clobber $BOARD_ETC/make.conf.board
    fi
    if [[ $FLAGS_quiet -eq $FLAGS_FALSE ]]; then
      warn "Board output directory '$BOARD_ROOT' already exists."
      warn "Not setting up board root. "
      warn "Use --force to clobber the board root and start again."
    fi
    exit 0
  fi
fi

sudo mkdir -p "$BOARD_ROOT" "${BOARD_ETC}" "${BOARD_PROFILE}"

if [ "${CHOST}" != "$FLAGS_toolchain" ] ; then
  # TODO(cmasone): Do this more cleanly, if we figure out what "cleanly" means.
  # Set up wrapper for pkg-config.  Point a board-specific wrapper at the
  # generic wrapper script created by crossdev-wrapper
  sudo ln -sf "/usr/bin/cross-pkg-config" \
      "/usr/bin/${FLAGS_toolchain}-pkg-config"
fi

# Setup the make.confs. We use the following:
#    make.conf             <- Overall target make.conf [arm, x86, etc. version]
#    make.conf.board_setup <- Declares CHOST, ROOT, etc.
#    make.conf.common      <- Common settings across all targets
#    make.conf.board       <- Optional board-supplied make.conf
if ${HOST_BOARD}; then
  sudo ln -sf "${CHROMIUMOS_CONFIG}/make.conf.${BOARD}" \
    "${BOARD_ETC}/make.conf"
  sudo cp -f "/etc/make.conf.host_setup" "${BOARD_ETC}/"

  # Setting up symlinks for bootstrapping multilib.
  # See http://crosbug.com/14498
  sudo mkdir -p "${BOARD_ROOT}/usr/lib64" "${BOARD_ROOT}/lib64"
  sudo ln -sf lib64 "${BOARD_ROOT}/lib"
  sudo ln -sf lib64 "${BOARD_ROOT}/usr/lib"

  # Copying some files for bootstrapping empty chroot.
  # See http://crosbug.com/14499
  sudo mkdir -p  ${BOARD_ETC}/xml/
  sudo cp /etc/xml/catalog ${BOARD_ETC}/xml/
  sudo mkdir -p  ${BOARD_ETC}/init.d/
  sudo cp /etc/init.d/functions.sh ${BOARD_ETC}/init.d/
fi
sudo ln -sf "${CHROMIUMOS_CONFIG}/make.conf.common-target" \
  "${BOARD_ETC}/make.conf.common"
cat <<EOF | sudo dd of="${BOARD_SETUP}" > /dev/null 2>&1
# Created by setup_board
CHOST="${FLAGS_toolchain}"
ROOT="${BOARD_ROOT}/"
BOARD_OVERLAY="${BOARD_OVERLAY_LIST}"
MAKEOPTS="-j${NUM_JOBS}"
PKG_CONFIG="pkg-config-${BOARD_VARIANT}"
BOARD_USE="${BOARD_VARIANT}"
EOF
if ! ${HOST_BOARD}; then
  sudo ln -sf "${CHROMIUMOS_CONFIG}/make.conf.${ARCH}-target" \
    "${BOARD_ETC}/make.conf"
  print_board_make_conf | sudo_clobber $BOARD_ETC/make.conf.board

  # We install the toolchain related bits after the BOARD_ROOT, BOARD_PROFILE
  # and BOARD_ETC directories have been created.
  install_toolchain_in_board
fi
# Setup make.globals and the profile.
sudo touch /etc/make.conf.user
sudo ln -sf /etc/make.globals "${BOARD_ROOT}/etc/make.globals"
sudo ln -sf /etc/make.conf.user "${BOARD_ROOT}/etc/make.conf.user"

# Select the profile to build based on the board and profile passed to
# setup_board.  The developer can later change profiles by running
# cros_choose_profile manually.
if ! cros_choose_profile \
       --board "${FLAGS_board}" \
       --board_overlay "${FLAGS_board_overlay}" \
       --variant "${FLAGS_variant}" \
       --profile "${FLAGS_profile}"; then
  error "Selecting profile failed, removing incomplete board directory!"
  sudo rm -rf "${BOARD_ROOT}"
  exit 1
fi


for wrapper in 'emerge --root-deps' ebuild eclean equery portageq \
               qcheck qfile qlist ; do
  generate_wrapper $wrapper
done

generate_pkgconfig_wrapper

CROS_WORKON_WRAPPER="/usr/local/bin/cros_workon-${BOARD_VARIANT}"
cat <<EOF | sudo dd of="$CROS_WORKON_WRAPPER" > /dev/null 2>&1
#!/bin/bash
exec cros_workon --board ${BOARD_VARIANT} "\$@"
EOF
sudo chmod +x "$CROS_WORKON_WRAPPER"

if ${HOST_BOARD}; then
  EMERGE_CMD="emerge"
  if [[ $FLAGS_fast -eq $FLAGS_TRUE ]]; then
    EMERGE_CMD="${GCLIENT_ROOT}/chromite/bin/parallel_emerge"
  fi
  PACKAGES="system hard-host-depends world"

  # First, rebuild all packages from scratch. This is needed to make sure
  # we rebuild all chroot packages.
  sudo -E $EMERGE_CMD --emptytree --with-bdeps=y $PACKAGES
  sudo eclean -d packages

  # Next, install our rebuilt packages into our separate root.
  HOST_FLAGS="--root=$BOARD_ROOT --update --verbose --deep --root-deps"
  HOST_FLAGS+=" --with-bdeps=y --newuse --jobs=$NUM_JOBS --usepkgonly"
  sudo -E $EMERGE_CMD $HOST_FLAGS --select=y $PACKAGES
  sudo cp -a "${PKGDIR}" $BOARD_ROOT/packages

  # Install cross-compilers.
  COMPILERS=$(equery l cross-*/* --format='=$cpv')
  sudo -E $EMERGE_CMD $HOST_FLAGS --select=n $COMPILERS

  # Setup needed symlinks for cross-compilers.
  sudo mkdir -p $BOARD_ROOT/usr/local/portage
  sudo cp -a ${CROSSDEV_OVERLAY} $BOARD_ROOT/usr/local/portage

  # Setup crossdev configuration for categories.
  sudo cp -a /etc/portage/* $BOARD_ROOT/etc/portage

  # The new chroot should have gcc for each target. Make sure that
  # the latest one is correctly selected. Ignore cat errors as not
  # all overlays will have a toolchain.conf.
  ALL_OVERLAYS=$(cros_overlay_list --all_boards)
  TARGETS=$(sed 's:#.*::' $(printf '%s/toolchain.conf ' ${ALL_OVERLAYS}) \
            2>/dev/null | sort -u)
  for target in ${TARGETS}; do
    libc=$(eval $(crossdev --show-target-cfg "${target}"); echo ${libc_pn})
    if [[ ${libc} == "glibc" ]] ; then
      # Install needed glibc tarball.
      cross_target_path=/var/lib/portage/pkgs/cross-${target}
      if [[ -e "$cross_target_path" ]] ; then
          sudo mkdir -p ${BOARD_ROOT}${cross_target_path}
          sudo cp -a ${cross_target_path}/glibc-* \
            ${BOARD_ROOT}${cross_target_path}
      fi
    fi

    CURRENT_GCC="$(gcc-config -c ${target})"
    sudo ROOT=${BOARD_ROOT} gcc-config ${CURRENT_GCC}
    CURRENT_BINUTILS="$(binutils-config -c ${target})"
    sudo ROOT=${BOARD_ROOT} binutils-config ${CURRENT_BINUTILS}
  done

  # Now cleanup paths referencing the ROOT from the *.la files.
  sudo find $BOARD_ROOT -type f -name '*.la' | xargs sudo \
      sed -i -e "s|$BOARD_ROOT/|/|g"
else
  # Now that the portageq-* wrappers have been created, we can add the binhost
  # config to make.conf.board.
  print_board_binhost_config | sudo_append $BOARD_ETC/make.conf.board

  #
  # Emerge the kernel headers into the board build root.
  #
  KERNEL_EMERGE_FLAGS="--select --quiet"
  if [[ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ||
        "${FLAGS_reuse_pkgs_from_local_boards}" -eq "${FLAGS_TRUE}" ]]; then
    KERNEL_EMERGE_FLAGS+=" --getbinpkg --usepkg"
  fi

  sudo -E "${EMERGE_WRAPPER}" ${KERNEL_EMERGE_FLAGS} \
    chromeos-base/kernel-headers

  unset KERNEL_EMERGE_FLAGS
fi

if [ $FLAGS_default -eq $FLAGS_TRUE ] ; then
  echo $BOARD_VARIANT > "$GCLIENT_ROOT/src/scripts/.default_board"
fi

echo "Done!"
echo "The SYSROOT is: ${BOARD_ROOT}"

# NOTE: Printing the working-on ebuilds does not only serve the informative
# purpose. It also causes the ${BOARD_ROOT}/etc/portage/package.* files to be
# regenerated.
WORKING_ON=$(cros_workon --board=${FLAGS_board} list)
if [ -n "${WORKING_ON}" ]; then
  echo
  echo "Currently working on the following ebuilds for this board:"
  echo "${WORKING_ON}"
fi