#!/bin/sh
# linaro-hwpack-install - Install a Linaro Hardware Pack.
#   This script is meant to run inside a chroot. It must not depend on anything
#   that's not in there.
# TODO: When upgrading to a newer hwpack, make sure packages and apt sources
# that are no longer needed are removed.

# Copyright (C) 2010, 2011 Linaro
#
# Author: Guilherme Salgado <guilherme.salgado@linaro.org>
#
# This file is part of Linaro Image Tools.
#
# Linaro Image Tools is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# Linaro Image Tools is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with Linaro Image Tools; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
# USA.

set -e

if [ -n "${TMPDIR+x}" ]; then
 echo -e "\nWARNING: TMPDIR variable is set. It will be unset because in chroot environment it likely doesn't exist and can lead to error messages.\n"
 unset TMPDIR
fi

LOCKFILE="/var/lock/hwpack"
TEMP_DIR=$(mktemp -d)
HWPACK_DIR="${TEMP_DIR}/unpacked"
INSTALL_LATEST="no"
FORCE_YES="no"
SOURCES_LIST_FILE="${TEMP_DIR}/sources.list"
APT_GET_OPTIONS="Dir::Etc::SourceList=${SOURCES_LIST_FILE}"
SUPPORTED_FORMATS="1.0 2.0 3.0"  # A space-separated list of hwpack formats.
FLASH_KERNEL_SKIP="true" 
export FLASH_KERNEL_SKIP # skip attempting to run flash-kernel-hooks
DISTRIBUTION=`grep '^ID=' /etc/os-release | sed 's/ID=//'`

sudo="sudo"
if [ $(id -u) -eq 0 ]; then
    sudo=""
fi

die() {
  echo -e "$@"
  exit 1
}

usage_msg="Usage: $(basename $0) [--install-latest] [--force-yes] [--extract-kernel-only] --hwpack-version <version> --hwpack-arch <architecture> --hwpack-name <name> HWPACK_TARBALL"
if [ $# -eq 0 ]; then
  die $usage_msg
fi

HWPACK_TARBALL_FOUND="no"
HWPACK_VERSION=""
HWPACK_ARCH=""
HWPACK_NAME=""
EXTRACT_KERNEL_ONLY="no"

while [ $# -gt 0 ]; do
  case "$1" in 
    --install-latest)
      INSTALL_LATEST="yes"
      shift;;
    --force-yes)
      FORCE_YES="yes"
      shift;;
    --hwpack-version)
      HWPACK_VERSION=$2
      shift;
      shift;;
    --hwpack-arch)
      HWPACK_ARCH=$2
      shift;
      shift;;
    --hwpack-name)
      HWPACK_NAME=$2
      shift;
      shift;;
    --extract-kernel-only)
      EXTRACT_KERNEL_ONLY="yes"
      shift;;
    --*)
      die $usage_msg "\nUnrecognized option: \"$1\"";;
    *)
      [ "$HWPACK_TARBALL_FOUND" = "yes" ] && die $usage_msg
      HWPACK_TARBALL="$1"
      HWPACK_TARBALL_FOUND="yes"
      shift;;
  esac
done

[ "$HWPACK_TARBALL_FOUND" = "no" ] && die $usage_msg
[ "$HWPACK_VERSION" = "" ] && die $usage_msg
[ "$HWPACK_ARCH" = "" ] && die $usage_msg
[ "$HWPACK_NAME" = "" ] && die $usage_msg

setup_hwpack() {
  # This creates all the directories we need.
  mkdir -p "$HWPACK_DIR"

  # Unpack the hwpack tarball. We don't download it here because the chroot may
  # not contain any tools that would allow us to do that.
  echo -n "Unpacking hardware pack ..."
  tar zxf "$HWPACK_TARBALL" -C "$HWPACK_DIR"
  echo "Done"

  # Check the format of the hwpack is supported.
  hwpack_format=$(cat ${HWPACK_DIR}/FORMAT)
  supported="false"
  for format in $SUPPORTED_FORMATS; do
    if [ "x$hwpack_format" = "x$format" ]; then
      supported="true"
      break
    fi
  done

  [ $supported = "true" ] || \
    die "Unsupported hwpack format: $hwpack_format. "\
        "Try using a newer version of $(basename $0)."

  # Check the architecture of the hwpack matches that of the host system.
  if [ "x$EXTRACT_KERNEL_ONLY" = "xno" ]; then
    # TODO: create a generic way to identify the architecture, without depending on dpkg
    [ "$HWPACK_ARCH" = `dpkg --print-architecture` ] || \
      die "Hardware pack architecture ($HWPACK_ARCH) does not match the host's architecture"
  fi
}

setup_apt_sources() {
  # Install the apt sources that contain the packages we need.
  for filename in $(ls "${HWPACK_DIR}"/sources.list.d/); do
    file="${HWPACK_DIR}"/sources.list.d/$filename
    should_install=0
    stripped_file=${TEMP_DIR}/$filename
    grep -v "\(^#\|^\s*$\)" $file > $stripped_file
    while read line; do
      # Only install files that have at least one line not present in the
      # existing sources lists.
      grep -qF "$line" $(find /etc/apt/sources.list.d/ -name '*.list') /etc/apt/sources.list \
        || should_install=1
    done < $stripped_file

    if [ $should_install -eq 1 ]; then
      $sudo cp $file /etc/apt/sources.list.d/hwpack.$filename
    fi
  done

  # Import the OpenPGP keys for the files installed above.
  for filename in $(ls "${HWPACK_DIR}"/sources.list.d.gpg/); do
    file="${HWPACK_DIR}"/sources.list.d.gpg/$filename
    $sudo apt-key add $file
  done

  # Add one extra apt source for the packages included in the hwpack and make
  # sure it's the first on the list of sources so that it gets precedence over
  # the others.
  echo "deb file:${HWPACK_DIR}/pkgs ./" > "$SOURCES_LIST_FILE"
  cat /etc/apt/sources.list >> "$SOURCES_LIST_FILE"

  if [ "$FORCE_YES" = "yes" ]; then
    FORCE_OPTIONS="--yes --force-yes"
  else
    FORCE_OPTIONS=""
  fi

  # Do two updates. The first doesn't try to download package lists:
  # * First update doesn't access net
  #   - not allowed to fail. Image file + hwpack should contain all packages
  #     needed to create image. If this update fails we have problems.
  # * Second update may fail
  #   - If can't download package updates (the only difference between the two
  #     commands), we should still be OK.
  echo "Updating apt package lists ..."
  $sudo apt-get $FORCE_OPTIONS -o "$APT_GET_OPTIONS" update -q --no-download --ignore-missing
  $sudo apt-get $FORCE_OPTIONS -o "$APT_GET_OPTIONS" update -q || true
}

setup_ubuntu_rootfs() {
  # Prevent daemons to start in the chroot
  echo "exit 101" > /usr/sbin/policy-rc.d
  chmod a+x /usr/sbin/policy-rc.d

  mv -f /sbin/start-stop-daemon /sbin/start-stop-daemon.REAL
  cat > /sbin/start-stop-daemon << EOF
#!/bin/sh

echo "Warning: Fake start-stop-daemon called, doing nothing"
EOF
chmod 755 /sbin/start-stop-daemon

if [ -x /sbin/initctl ]; then
  mv -f /sbin/initctl /sbin/initctl.REAL
  cat > /sbin/initctl << EOF
#!/bin/sh

echo "Warning: Fake initctl called, doing nothing"
EOF
    chmod 755 /sbin/initctl
  fi

  # Create dummy fstab. fsck initramfs-tools hook is reading fstab entries
  # in order to copy e2fsck into initramfs image
  [ -f /etc/fstab ] && mv -f /etc/fstab /etc/fstab.REAL
  echo "UUID=00000000-0000-0000-0000-000000000000 / ext4 defaults 0 1" > /etc/fstab
}

install_deb_packages() {
  echo -n "Installing packages ..."

  # "newer" hwpacks contain a dependency package whose Depends is the
  # same as the packages config setting from the file the hwpack was
  # build from.  But if we just installed that, a newer version of a
  # package than that in the hwpack might have made it to the main
  # archive and apt-get would install that instead.  So we install the
  # specific package versions that make up the hwpack.  /That/ however
  # would leave all the packages from the hwpack marked as manually
  # installed, so if a newer hwpack was installed over the top which no
  # longer depended on one of the packages the older one did, the
  # package would not be eligible for autoremoval.  So we mark the all
  # packages newly installed as part of hwpack installed (apart from the
  # dependency package) as automatically installed with apt-get
  # markauto.
  #
  # For "older" hwpacks that don't have a dependency package, we just
  # manually install the contents of the hwpack.

  dependency_package="hwpack-${HWPACK_NAME}"
  if grep -q "^${dependency_package}=${HWPACK_VERSION}\$" "${HWPACK_DIR}"/manifest; then
    DEP_PACKAGE_PRESENT="yes"
  else
    DEP_PACKAGE_PRESENT="no"
  fi

  packages_without_versions=`sed 's/=.*//' "${HWPACK_DIR}"/manifest`
  packages_with_versions=`cat "${HWPACK_DIR}"/manifest`

  if [ "$INSTALL_LATEST" = "yes" ]; then
    packages="${packages_without_versions}"
  else
    packages="${packages_with_versions}"
  fi

  if [ "$DEP_PACKAGE_PRESENT" = "yes" ]; then
    to_be_installed=
    for package in $packages_without_versions; do
      if [ "${package}" != "${dependency_package}" ]; then
        { dpkg --get-selections $package 2>/dev/null| grep -qw 'install$'; } || to_be_installed="$to_be_installed $package"
      fi
    done
  fi

  $sudo apt-get $FORCE_OPTIONS -o "$APT_GET_OPTIONS" install ${packages}

  if [ "$DEP_PACKAGE_PRESENT" = "yes" ]; then
    if [ -n "${to_be_installed}" ]; then
      $sudo apt-get $FORCE_OPTIONS -o "$APT_GET_OPTIONS" markauto ${to_be_installed}
    fi
  fi
}

extract_kernel_packages() {
  echo "Extracting all kernel packages ..."

  # We assume the hwpack is always available at the rootfs
  ROOTFS_DIR=$(dirname $HWPACK_TARBALL)

  ls ${HWPACK_DIR}/pkgs/linux-[ih]*.deb | while read pkg; do
    echo "Extracting package `basename $pkg`"
    dpkg-deb -x ${pkg} $ROOTFS_DIR
  done

  ls ${HWPACK_DIR}/pkgs/*-pre-boot*.deb | while read pkg; do
    echo "Extracting package `basename $pkg`"
    dpkg-deb -x ${pkg} $ROOTFS_DIR
  done

  ls ${HWPACK_DIR}/pkgs/uefi-image-*.deb | while read pkg; do
    echo "Extracting package `basename $pkg`"
    dpkg-deb -x ${pkg} $ROOTFS_DIR
  done

  # manually generate modules.dep
  ls $ROOTFS_DIR/lib/modules | while read kernel; do
    depmod -b $ROOTFS_DIR ${kernel} || true
  done;
}

cleanup() {
  # Ensure our temp dir and apt sources are removed.
  echo -n "Cleaning up ..."
  rm -rf $TEMP_DIR
  if [ "x$EXTRACT_KERNEL_ONLY" = "xno" ]; then
    rm -f /usr/sbin/policy-rc.d
    mv -f /sbin/start-stop-daemon.REAL /sbin/start-stop-daemon
    if [ -x /sbin/initctl.REAL ]; then
      mv -f /sbin/initctl.REAL /sbin/initctl
    fi
    rm -f /etc/fstab
    [ -f /etc/fstab.REAL ] && mv -f /etc/fstab.REAL /etc/fstab
    # Do two updates. The first doesn't try to download package lists:
    # * First update doesn't access net
    #   - not allowed to fail. Image file + hwpack should contain all packages
    #     needed to create image. If this update fails we have problems.
    # * Second update may fail
    #   - If can't download package updates (the only difference between the two
    #     commands), we should still be OK.
    $sudo apt-get update -qq --no-download --ignore-missing
    $sudo apt-get update -qq || true
  fi
  echo "Done"
}

## main

# Try to acquire fd #9 (i.e. /var/lock/hwpack)
# Using 9 as the file descriptor because of https://launchpad.net/bugs/249620
exec 9>$LOCKFILE
flock -n 9 || die "Could not acquire lock: $LOCKFILE"

# From now on we'll be making changes to the system, so we need to clean
# things up when the script exits.
trap cleanup EXIT

# Extract and set up the hwpack at the rootfs
setup_hwpack

# In case we only care about the kernel, don't mess up with the system
if [ "x$EXTRACT_KERNEL_ONLY" = "xno" ]; then
  setup_apt_sources
  setup_ubuntu_rootfs
  install_deb_packages
else
  extract_kernel_packages
fi

echo "Done"