#!/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

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

assert_not_root_user

# Developer-visible flags.
DEFINE_string board "${DEFAULT_BOARD}" \
  "The board to build packages for."
DEFINE_boolean usepkg "${FLAGS_TRUE}" \
  "Use binary packages to bootstrap when possible."
DEFINE_boolean usepkgonly "${FLAGS_FALSE}" \
  "Only use binary packages to bootstrap; abort if any are missing."
DEFINE_boolean workon "${FLAGS_TRUE}" \
  "Force-build workon packages."
DEFINE_boolean showoutput "${FLAGS_FALSE}" \
  "Show all output from parallel_emerge."
DEFINE_boolean withautotest "${FLAGS_TRUE}" \
  "Build autotest client code."
DEFINE_boolean withdebugsymbols "${FLAGS_FALSE}" \
  "Install the debug symbols for all packages"
DEFINE_string eventfile "${DEFAULT_EVENT_FILE}" \
  "Define the file that event logs will be written."
DEFINE_boolean withrevdeps "${FLAGS_TRUE}" \
  "Calculate reverse dependencies on changed ebuilds."
DEFINE_boolean autosetgov "${FLAGS_FALSE}" \
  "Automatically set cpu governor to 'performance'."
DEFINE_boolean use_any_chrome "${FLAGS_TRUE}" \
  "Use any Chrome prebuilt available, even if the prebuilt doesn't match exactly."

# The --board_root flag specifies the environment variables ROOT and PKGDIR.
# This allows fetching and emerging of all packages to specified board_root.
# Note that --board_root will setup the board normally in /build/$BOARD, if it's
# not setup yet. It also expects the toolchain to already be installed in the
# board_root. --usepkgonly and --norebuild are required, because building is not
# supported when board_root is set.
# enforce this)."
DEFINE_string board_root "" \
  "Emerge packages to board_root."

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

build_packages updates the set of binary packages needed by Chrome OS. It will
cross compile all packages that have been updated into the given target's root
and build binary packages as a side-effect. The output packages will be picked
up by the build_image script to put together a bootable Chrome OS image.

If [packages] are specified, only build those specific packages (and any
dependencies they might need).

For the fastest builds, use --nowithautotest --noworkon.
"

# 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 accept_licenses "" \
  "Licenses to append to the accept list."
DEFINE_integer jobs -1 \
  "How many packages to build in parallel at maximum."
DEFINE_boolean norebuild "${FLAGS_FALSE}" \
  "Don't automatically rebuild dependencies."
DEFINE_boolean skip_chroot_upgrade "${FLAGS_FALSE}" \
  "Don't run the chroot upgrade automatically; use with care."
DEFINE_boolean skip_toolchain_update "${FLAGS_FALSE}" \
  "Don't update toolchain automatically."
DEFINE_boolean withdev "${FLAGS_TRUE}" \
  "Build useful developer friendly utilities."
DEFINE_boolean withdebug "${FLAGS_TRUE}" \
  "Build debug versions of Chromium-OS-specific packages."
DEFINE_boolean withfactory "${FLAGS_TRUE}" \
  "Build factory installer."
DEFINE_boolean withtest "${FLAGS_TRUE}" \
  "Build packages required for testing."

# 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."

# --run_goma option is designed to be used on bots.
# If you're trying to build pacakges with goma in your local dev env, this is
# *not* the option you're looking for. Please see comments below.
# This option; 1) starts goma, 2) builds packages (expecting that goma is
# used), then 3) stops goma explicitly.
# 3) is a request from the goma team, so that stats/logs can be taken.
# Note: GOMA_DIR and GOMA_SERVICE_ACCOUNT_JSON_FILE are expected to be passed
# via env var.
#
# In local dev env cases, compiler_proxy is expected to keep running.
# In such a case;
#   $ python ${GOMA_DIR}/goma_ctl.py ensure_start
#   $ ./build_packages (... and options without --run_goma ...)
# is an expected commandline sequence. If you set --run_goma flag while
# compiler_proxy is already running, the existing compiler_proxy will be
# stopped.
DEFINE_boolean run_goma "${FLAGS_FALSE}" \
  "If set to true, (re)starts goma, builds packages, and then stops goma."

# Parse command line
FLAGS "$@" || exit 1
eval set -- "${FLAGS_ARGV}"

# Die on any errors.
switch_to_strict_mode

# This is a temporary measure to help the goma team check the configs while
# they transition their backend service.
# TODO(crbug.com/1032290): Delete after the goma RBE transition is complete.
if [[ "${FLAGS_run_goma}" -eq "${FLAGS_TRUE}" ]]; then
  info "Environment:"
  env
  info "End Environment."
fi

# Right now build_packages has to be run from scripts/
. ${SRC_ROOT}/third_party/chromiumos-overlay/chromeos/config/chromeos_version.sh

# On some systems, powersave can take a long time to ramp up.  Inform the user
# so they can get faster builds.  https://crbug.com/1008932
if grep -qs powersave \
     /sys/devices/system/cpu/cpufreq/policy*/scaling_governor; then
  # Make sure we can actually support "performance".
  if grep -qs performance \
      /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors; then
    if [[ "${FLAGS_autosetgov}" -eq "${FLAGS_TRUE}" ]]; then
      info "Temporarily setting cpu governor to 'performance'"
      trap "sudo cpupower -c all frequency-set -g powersave >&/dev/null" EXIT
      sudo cpupower -c all frequency-set -g performance >&/dev/null
    else
      warn "Current CPU governor set to 'powersave' which can slow down builds."
      warn "Use --autosetgov to automatically (and temporarily) switch to" \
        "'performance'."
    fi
  fi
fi

if [[ -z "${FLAGS_board}" ]]; then
  echo "Error: --board is required."
  exit 1
fi

# Before we can run any tools, we need to update chroot or setup_board.
UPDATE_ARGS=()
if [[ -n ${FLAGS_accept_licenses} ]]; then
  UPDATE_ARGS+=( --accept-licenses "${FLAGS_accept_licenses}" )
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 [ "${FLAGS_reuse_pkgs_from_local_boards}" -eq "${FLAGS_TRUE}" ]; then
  UPDATE_ARGS+=( --reuse-pkgs-from-local-boards )
fi
if [ "${FLAGS_skip_toolchain_update}" -eq "${FLAGS_TRUE}" ]; then
  UPDATE_ARGS+=( --skip-toolchain-update )
fi
if [ "${FLAGS_skip_chroot_upgrade}" -eq "${FLAGS_TRUE}" ]; then
  UPDATE_ARGS+=( --skip-chroot-upgrade )
fi
if [[ -n ${FLAGS_board_root} ]]; then
  UPDATE_ARGS+=( --board-root "${FLAGS_board_root}" )
fi

setup_board --quiet --board=${FLAGS_board} "${UPDATE_ARGS[@]}"

sudo_clear_shadow_locks "/build/${FLAGS_board}"
PORTAGE_BINHOST=$(portageq-${FLAGS_board} envvar 'PORTAGE_BINHOST')
info "PORTAGE_BINHOST: ${PORTAGE_BINHOST}"


# Setup all the emerge command/flags.
EMERGE_FLAGS=( -uDNv --backtrack=30 --newrepo )

EMERGE_CMD=(
  "${CHROMITE_BIN}/parallel_emerge"
  --board=${FLAGS_board}
)

if [[ "${FLAGS_use_any_chrome}" -eq "${FLAGS_TRUE}" ]]; then
  EMERGE_CMD+=( "--force-remote-binary=chromeos-base/chromeos-chrome" )
fi

EMERGE_CMD+=( ${EXTRA_BOARD_FLAGS} )

if [[ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ||
      "${FLAGS_reuse_pkgs_from_local_boards}" -eq "${FLAGS_TRUE}" ||
      "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
  # Use binary packages. Include all build-time dependencies,
  # so as to avoid unnecessary differences between source
  # and binary builds.
  EMERGE_FLAGS+=( --getbinpkg --with-bdeps y )
  if [[ ${FLAGS_usepkgonly} -eq ${FLAGS_TRUE} ]]; then
    EMERGE_FLAGS+=( --usepkgonly )
  else
    EMERGE_FLAGS+=( --usepkg )
  fi
fi

if [[ "${FLAGS_jobs}" -ne -1 ]]; then
  EMERGE_FLAGS+=( --jobs=${FLAGS_jobs} )
fi

if [[ "${FLAGS_norebuild}" -eq "${FLAGS_FALSE}" ]]; then
  EMERGE_FLAGS+=( --rebuild-if-new-rev )
fi
if [[ "${FLAGS_showoutput}" -eq "${FLAGS_TRUE}" ]]; then
  EMERGE_FLAGS+=( --show-output )
fi

if [[ "${FLAGS_withdebug}" -eq "${FLAGS_FALSE}" ]]; then
  export USE="${USE} -cros-debug"
fi

# Figure out which packages we should be building.
PACKAGES=( "$@" )
# Force rebuild chromeos-config because it is extremely cheap, and we do not
# want to reuse stale configs.
FORCE_LOCAL_BUILD_PKGS=( chromeos-base/chromeos-config )
if [[ $# -eq 0 ]]; then
  PACKAGES=( virtual/target-os )
  if [[ "${FLAGS_withdev}" -eq "${FLAGS_TRUE}" ]]; then
    PACKAGES+=( virtual/target-os-dev )
  fi
  if [[ "${FLAGS_withfactory}" -eq "${FLAGS_TRUE}" ]]; then
    PACKAGES+=( virtual/target-os-factory )
    PACKAGES+=( virtual/target-os-factory-shim )
  fi
  if [[ "${FLAGS_withtest}" -eq "${FLAGS_TRUE}" ]]; then
    PACKAGES+=( virtual/target-os-test )
    # chromeos-ssh-testkeys may generate ssh keys if the right USE flag is set.
    # We force rebuilding this package from source every time, so that
    # consecutive builds don't share ssh keys.
    FORCE_LOCAL_BUILD_PKGS+=( chromeos-base/chromeos-ssh-testkeys )
  fi
  if [[ "${FLAGS_withautotest}" -eq "${FLAGS_TRUE}" ]]; then
    PACKAGES+=( chromeos-base/autotest-all )
  fi
fi

info "Rebuilding Portage cache"
# Before running any emerge operations, regenerate the Portage dependency cache
# in parallel.
"${EMERGE_CMD[@]}" --regen --quiet

# Verify that all packages can be emerged from scratch, without any
# backtracking. Only print the output if this step fails.
info "Checking package dependencies are correct: ${PACKAGES[*]}"
if ! OUTPUT=$(emerge-${FLAGS_board} -pe --backtrack=0 \
              "${PACKAGES[@]}" 2>&1); then
  printf "%s\n" "${OUTPUT}"
  die_notrace "emerge detected broken ebuilds. See error message above."
fi

# Build cros_workon packages when they are changed.
CROS_WORKON_PKGS=()
if [ "${FLAGS_workon}" -eq "${FLAGS_TRUE}" ]; then
  LIST_MODIFIED_PACKAGES="${CHROMITE_BIN}/cros_list_modified_packages"
  MODIFIED_PACKAGES=( $("${LIST_MODIFIED_PACKAGES}" --board=${FLAGS_board}) )
  info "cros_workon modified packages '${MODIFIED_PACKAGES[*]}' detected"
  CROS_WORKON_PKGS+=( "${MODIFIED_PACKAGES[@]}" )

  # TODO(anush): Make chrome a fake cros-workon package.
  if [[ -n "${CHROME_ORIGIN}" ]]; then
    CROS_WORKON_PKGS+=( chromeos-base/chromeos-chrome )
  fi
fi

# cros_workon packages always have to be rebuilt.
FORCE_LOCAL_BUILD_PKGS+=( "${CROS_WORKON_PKGS[@]}" )

if [[ -n "${FLAGS_board_root}" ]]; then
  export ROOT="${FLAGS_board_root}"
  export PORTAGE_CONFIGROOT="${ROOT}"
  export SYSROOT="${ROOT}"
  export PKGDIR="${ROOT}"/packages
fi

# Temporarily modify the emerge flags so we can calculate the revdeps
# on the modified packages.
if [[ "${FLAGS_withrevdeps}" -eq "${FLAGS_TRUE}" ]]; then
  info "starting reverse dependency calculations ..."
  SIM_EMERGE_FLAGS=( "${EMERGE_FLAGS[@]}" --pretend --columns )

  if [[ ${#PACKAGES[@]} -gt 0 ]]; then
    SIM_EMERGE_FLAGS+=(
      --reinstall-atoms="${PACKAGES[*]}"
      --usepkg-exclude="${PACKAGES[*]}"
    )
  fi

  # Calculate only the ebuild changes from the emerge simulation ignoring
  # the virtual packages and the forced rebuild of autotest-all package.
  BASE_INSTALL_PKGS=( $( \
    sudo -E "${EMERGE_CMD[@]}" "${SIM_EMERGE_FLAGS[@]}" "${PACKAGES[@]}" | \
    sed -n -E '/^\[ebuild /{s:^[^]]+\] +::;s: .*::;p}' | \
    grep -v -e '^virtual/' -e '^chromeos-base/autotest-all' | sort -u ) )

  MOD_PKGS=()
  if [[ "${#BASE_INSTALL_PKGS[@]}" -gt 0 ]]; then
    info "New packages being installed: ${BASE_INSTALL_PKGS[*]}."
    # Convert specific versions into base package names
    MOD_PKGS+=( $(\
    equery-${FLAGS_board} list -p -o --format='$category/$name' \
      "${BASE_INSTALL_PKGS[@]}" | sort -u ) )
    # Remove Chrome as rebuilding it is expensive and almost never makes sense.
    # Ignore grep exit status in case chromeos-chrome is the only package.
    MOD_PKGS=( $(printf '%s\n' "${MOD_PKGS[@]}" | \
      grep -v 'chromeos-base/chromeos-chrome' || :) )
  fi

  FORCE_LOCAL_BUILD_PKGS+=( "${MOD_PKGS[@]}" )

  if [[ "${#MOD_PKGS[@]}" -gt 0 ]]; then
    info "calculating reverse dependencies on packages: ${MOD_PKGS[*]}"
    REV_DEPS=( $(\
      equery-${FLAGS_board} -q depends --indirect "${MOD_PKGS[@]}" |\
      awk '{print $1}' | grep -v ^virtual/ | sort -u) )
    if [[ "${#REV_DEPS[@]}" -gt 0 ]]; then
      # Convert specific versions into base package names
      RMOD_PKGS=( $(\
        equery-${FLAGS_board} -q list -p -o --format='$category/$name' \
        "${REV_DEPS[@]}" | sort -u ) )
      # Remove Chrome as rebuilding it is expensive and almost never makes
      # sense.  Ignore grep exit status in case chromeos-chrome is the only
      # package.
      RMOD_PKGS=( $(printf '%s\n' "${RMOD_PKGS[@]}" | \
        grep -v 'chromeos-base/chromeos-chrome' || :) )
      info "final reverse dependencies that will be rebuilt: ${RMOD_PKGS[*]}"
      FORCE_LOCAL_BUILD_PKGS+=( "${RMOD_PKGS[@]}" )
    fi
  fi
fi # end FLAGS_withrevdeps

if [[ ${#FORCE_LOCAL_BUILD_PKGS[@]} -gt 0 ]]; then
  EMERGE_FLAGS+=(
    --reinstall-atoms="${FORCE_LOCAL_BUILD_PKGS[*]}"
    --usepkg-exclude="${FORCE_LOCAL_BUILD_PKGS[*]}"
  )
fi

# A list of critical system packages that should never be incidentally
# reinstalled as a side effect of build_packages. All packages in this list
# are special cased to prefer matching installed versions, overriding the
# typical logic of upgrading to the newest available version.
#
# This list can't include any package that gets installed to a board!
# Packages such as LLVM or binutils must not be in this list as the normal
# rebuild logic must still apply to them for board targets.
#
# TODO(crbug/1050752): Remove this list and the corresponding arguments
# to `emerge` below once we figure out how to exclude toolchain packages from
# being upgraded transitively via BDEPEND relations.
CRITICAL_SDK_PACKAGES=(
  "sys-libs/glibc"
  "sys-devel/gcc"
)

info "Merging board packages now"
(
  # Support goma on bots. This has to run in subshell, otherwise EXIT trap
  # handler is overwritten.
  if [[ "${FLAGS_run_goma}" -eq "${FLAGS_TRUE}" ]]; then
    info "Starting goma compiler_proxy."
    goma_ctl="${GOMA_DIR:-${HOME}/goma}/goma_ctl.py"
    "${goma_ctl}" restart
    trap "'${goma_ctl}' stop" EXIT
  fi

  sudo -E "${EMERGE_CMD[@]}" "${EMERGE_FLAGS[@]}" "${PACKAGES[@]}" \
    --useoldpkg-atoms="${CRITICAL_SDK_PACKAGES[*]}" \
    --rebuild-exclude="${CRITICAL_SDK_PACKAGES[*]}"
)

echo "Builds complete"

if [[ ${FLAGS_withdebugsymbols} -eq ${FLAGS_TRUE} ]]; then
  info "fetching the debug symbols"
  sudo -E "${CHROMITE_BIN}/cros_install_debug_syms" \
    "--board=${FLAGS_board}" "--all"
fi

command_completed
echo "Done"