util/vpd_icc

#!/bin/sh
# Copyright 2020 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.
#
# Packs ICC profiles to VPD, or to create local ICC profile files from VPD.

VPD_KEY="display_profiles"
CACHE_DIR="/var/cache/display_profiles/vpd"
ICC_EXT=".icc"

error() {
  echo "ERROR: $*" >&2
}

die() {
  local msg="${1:-Aborted Execution.}"
  error "${msg}"
  exit 1
}

is_valid_product_id() {
  local name="$1"
  if [ "${#name}" = 8 ] && [ "$((0x${name}))" -gt 0 ]; then
    return 0
  fi
  return 1
}

extract_from_vpd() {
  local raw_value="$(vpd_get_value "${VPD_KEY}")"
  if [ -z "${raw_value}" ]; then
    return
  fi
  # raw_value format: product_id:base64(gzip(icc))
  local product_id="${raw_value%%:*}"
  local content="${raw_value#*:}"
  if ! is_valid_product_id "${product_id}"; then
    return
  fi
  local icc_path="${CACHE_DIR}/${product_id}${ICC_EXT}"
  echo "${content}" | base64 -d | gzip -cd >"${icc_path}" ||
    rm -f "${icc_path}"
  if [ -s "${icc_path}" ]; then
    echo "Exported ICC profile for ${product_id}"
  fi
}

import_from_file() {
  local path="$1"
  local base="$(basename "${path}")"
  local product_id="${base%%.*}"

  if ! is_valid_product_id "${product_id}"; then
    die "Invalid input file name (must be 8-digits hex): ${path}"
  fi
  local content="$(gzip -c <"${path}" | base64 -w 0)"
  if [ -z "${content}" ]; then
    die "Failed to encode from ${path}."
  fi
  local cmd="${VPD_KEY}=${product_id}:${content}"
  echo "New VPD: ${cmd}"
  vpd -i RO_VPD -s "${cmd}"
}

main() {
  case "$#" in
    0)
      extract_from_vpd
      ;;
    1)
      import_from_file "$1"
      ;;
    *)
      die "Usage: $0 [ICCFile]"
      ;;
  esac
}
main "$@"