common

#!/bin/sh
# 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.

# TODO(josephsih): need to have some way to derive this list
# from system attributes automatically.
DEVICES_WITHOUT_BUILT_IN_TOUCHPAD="stumpy"

set_pref_vars() {
  local name=$1
  PREF_FILE=$(eval echo \$PREF_${name}_FILE)
  PREF_VALID=$(eval echo \$PREF_${name}_VALID)
  PREF_DEFAULT=$(eval echo \$PREF_${name}_DEFAULT)
}

load_pref() {
  local name="$1"
  set_pref_vars "$name"
  local file_size="$(stat -c %s $PREF_FILE)"
  if [ "$file_size" != "2" ]; then
    # invalid file size
    echo "$PREF_DEFAULT"
    return
  fi
  local value="$(cat "$PREF_FILE")"
  case $value in
    $PREF_VALID) echo "$value";;
    *) echo "$PREF_DEFAULT";;
  esac
}

store_pref() {
  local name="$1"
  local value="$2"
  set_pref_vars "$name"
  case $value in
    $PREF_VALID) ;;
    *) return;;
  esac
  echo $value > "$PREF_FILE"
}

find_pad() {
  # Use xinput to find if any touchpad device is present. Then find its
  # device ID number.
  return `xinput list | \
    awk '/[pP]ad|cyapa/ { for (i=1; i<NF; i++) \
         if ($i ~/id=/) print substr($i, 4) }'`
}