# SPDX-License-Identifier: GPL-2.0-or-later
# Copyright (C) 2018 Team LibreELEC (https://libreelec.tv)
# Copyright (C) 2018-present Team CoreELEC (https://coreelec.org)
# Copyright (C) 2023 JELOS (https://github.com/JustEnoughLinuxOS)

### FUNCTION HELPERS ###
# die (message, code) abort with optional message and code
die() {
  if [ -n "$1" ]; then
    echo -e "$1" >&2
  fi
  exit "${2:-1}"
}

# return 0 if $2 in space-separated list $1, otherwise return 1
listcontains() {
  if [ -n "$1" -a -n "$2" ]; then
    [[ ${1} =~ (^|[[:space:]])${2}($|[[:space:]]) ]] && return 0 || return 1
  else
    return 1
  fi
}

# remove item(s) from list.
# looping makes it greedy (eg. listremoveitem "abc def ghi" "(abc|def)" removes both "abc" and "def").
listremoveitem() {
  local data="${1}" odata tmp_array
  if [ -n "$1" -a -n "$2" ]; then
    while [ : ]; do
      odata="${data}"
      data="$(echo "${data}" | sed -E "s (^|[[:space:]])${2}($|[[:space:]]) \  g")"
      [ "${odata}" = "${data}" ] && break
    done
  fi
  # Use array word splitting to squash spaces
  tmp_array=(${data})
  echo "${tmp_array[@]}"
}

print_color() {
  local clr_name="$1" clr_text="$2" clr_actual
  local black red green yellow blue magenta cyan white endcolor
  local boldblack boldred boldgreen boldyellow boldblue boldmagenta boldcyan boldwhite

  [ -z "${clr_name}" ] && return 0

  if [ "${DISABLE_COLORS}" = "yes" ]; then
    [ $# -eq 2 ] && echo -en "${clr_text}"
    return 0
  fi

  black="\e[0;30m"
  boldblack="\e[1;30m"
  red="\e[0;31m"
  boldred="\e[1;31m"
  green="\e[0;32m"
  boldgreen="\e[1;32m"
  yellow="\e[0;33m"
  boldyellow="\e[1;33m"
  blue="\e[0;34m"
  boldblue="\e[1;34m"
  magenta="\e[0;35m"
  boldmagenta="\e[1;35m"
  cyan="\e[0;36m"
  boldcyan="\e[1;36m"
  white="\e[0;37m"
  boldwhite="\e[1;37m"
  endcolor="\e[0m"

  # $clr_name can be a color variable (boldgreen etc.) or a
  # "standard" color determined by an indirect name (CLR_ERROR etc.)
  #
  # If ${!clr_name} doesn't exist then assume it's a standard color.
  # If ${!clr_name} does exist then check it's not a custom color mapping.
  # Custom color mappings can be configured in options files.
  #
  clr_actual="${!clr_name}"

  if [ -n "${clr_actual}" ]; then
    clr_actual="${!clr_actual}"
  else
    case "${clr_name}" in
      CLR_ERROR)        clr_actual="${boldred}";;
      CLR_WARNING)      clr_actual="${boldred}";;
      CLR_WARNING_DIM)  clr_actual="${red}";;

      CLR_APPLY_PATCH)  clr_actual="${boldgreen}";;
      CLR_AUTORECONF)   clr_actual="${boldmagenta}";;
      CLR_BUILD)        clr_actual="${boldyellow}";;
      CLR_TOOLCHAIN)    clr_actual="${boldmagenta}";;
      CLR_CLEAN)        clr_actual="${boldred}";;
      CLR_FIXCONFIG)    clr_actual="${boldyellow}";;
      CLR_GET)          clr_actual="${boldcyan}";;
      CLR_INFO)         clr_actual="${boldgreen}";;
      CLR_INSTALL)      clr_actual="${boldgreen}";;
      CLR_PATCH_DESC)   clr_actual="${boldwhite}";;
      CLR_TARGET)       clr_actual="${boldwhite}";;
      CLR_UNPACK)       clr_actual="${boldcyan}";;

      CLR_ENDCOLOR)     clr_actual="${endcolor}";;

      *)                clr_actual="${endcolor}";;
    esac
  fi

  if [ $# -eq 2 ]; then
    echo -en "${clr_actual}${clr_text}${endcolor}"
  else
    echo -en "${clr_actual}"
  fi
}

# print build progress messages
# param1: message color, p2: label, p3: text, p4: indent (optional)
build_msg() {
  local spaces

  [ -n "${BUILD_INDENT}" ] && spaces="$(printf "%${BUILD_INDENT}c" " ")" || spaces=""

  if [ -n "${3}" ]; then
    echo -e "${spaces}$(print_color "${1}" "${2}")      ${3}" >&${SILENT_OUT}
  else
    echo -e "${spaces}$(print_color "${1}" "${2}")" >&${SILENT_OUT}
  fi

  # pad left space to create "indent" effect
  if [ "${4}" = "indent" ]; then
    export BUILD_INDENT=$((${BUILD_INDENT:-0}+${BUILD_INDENT_SIZE}))
  elif [ -n "${4}" ]; then
    die "ERROR: ${0} unexpected parameter: ${4}"
  fi
}

# prints a warning if the file slated for removal doesn't exist
# this allows us to continue instead of bailing out with just "rm"
safe_remove() {
  local path="$1"

  [ -z "${path}" ] && return 0

  if [ -e "${path}" -o -L "${path}" ]; then
    rm -r "${path}"
  elif [ -n "${PKG_NAME}" ]; then
    print_color CLR_WARNING "safe_remove: path does not exist: [${PKG_NAME}]: ${path}\n"
  else
    print_color CLR_WARNING "safe_remove: path does not exist: ${path}\n"
  fi
}

### BUILDSYSTEM HELPERS ###
# check if a flag is enabled
# $1: flag-name, $2: default (yes/no), $3: ingenious check (none,only-disable,only-enable)
# set variable PKG_[FLAG]_[HOST/TARGET]_ENABLED=(yes/no)
# return 0 if flag is enabled, otherwise 1
flag_enabled() {
  # make flag name upper case and replace hyphen with underscore, to use as variable name
  local flag_name=${1^^}
  [[ ${flag_name} =~ : ]] || flag_name+="_TARGET"
  flag_name="PKG_${flag_name//[:-]/_}_ENABLED"

  # check flag
  if [ -n "${PKG_BUILD_FLAGS}" ] && listcontains "${PKG_BUILD_FLAGS}" "[+]?$1"; then
    if [ "${3:none}" = "only-disable" ]; then
      die "ERROR: $1 cannot enable via PKG_BUILD_FLAGS (found in ${PKG_NAME})"
    fi
    declare ${flag_name}="yes"
    return 0
  elif [ "$2" = "yes" ] && ! listcontains "${PKG_BUILD_FLAGS}" "-$1"; then
    declare ${flag_name}="yes"
    return 0
  else
    if [ "${3:none}" = "only-enable" ]; then
      die "ERROR: $1 cannot disable via PKG_BUILD_FLAGS (found in ${PKG_NAME})"
    fi
    declare ${flag_name}="no"
    return 1
  fi
}

setup_pkg_config_target() {
  export PKG_CONFIG="${TOOLCHAIN}/bin/pkg-config"
  export PKG_CONFIG_PATH=""
  export PKG_CONFIG_LIBDIR="${SYSROOT_PREFIX}/usr/lib/pkgconfig:${SYSROOT_PREFIX}/usr/share/pkgconfig"
  export PKG_CONFIG_SYSROOT_DIR="${SYSROOT_PREFIX}"
  export PKG_CONFIG_ALLOW_SYSTEM_CFLAGS=1
  export PKG_CONFIG_ALLOW_SYSTEM_LIBS=1
}

setup_pkg_config_host() {
  export PKG_CONFIG="${TOOLCHAIN}/bin/pkg-config"
  export PKG_CONFIG_PATH=""
  export PKG_CONFIG_LIBDIR="${TOOLCHAIN}/lib/pkgconfig:${TOOLCHAIN}/share/pkgconfig"
  export PKG_CONFIG_SYSROOT_DIR=""
  unset PKG_CONFIG_ALLOW_SYSTEM_CFLAGS
  unset PKG_CONFIG_ALLOW_SYSTEM_LIBS
}

# args: linker, default availability yes/no
linker_allowed() {
  if flag_enabled "$1" "$2"; then
    # bfd is always available, others need to be enabled with <LINKER>_SUPPORT="yes"
    local linker_support="${1^^}_SUPPORT"
    if [ "$1" = "bfd" ] || [ "${!linker_support}" = "yes" ]; then
      return 0
    fi
  fi
  return 1
}

# return target linker to use for a package
get_target_linker() {
  # all known linkers, in descending order of priority
  # those are candidates for explicit opt-in via PKG_BUILD_FLAGS
  local all_linkers="mold gold bfd"

  # linkers to choose from unless disabled via PKG_BUILD_FLAGS
  local linker_candidates="${DEFAULT_LINKER:-bfd} ${all_linkers}"

  local linker

  # check if package prefers a specific linker
  for linker in ${all_linkers}; do
    if linker_allowed "${linker}" "no"; then
      echo "${linker}"
      return
    fi
  done

  # select linker which isn't disabled by PKG_BUILD_FLAGS
  for linker in ${linker_candidates}; do
    if linker_allowed "${linker}" "yes"; then
      echo "${linker}"
      return
    fi
  done

  # none of our linkers matched, use the compiler's default linker
  echo "compiler_default"
}

setup_toolchain() {
  if [ "$LTO_SUPPORT" = "yes" ]; then
    if flag_enabled "lto-parallel" "no"; then
      TARGET_CFLAGS+=" ${FLAGS_OPTIM_LTO_PARALLEL} ${FLAGS_OPTIM_LTO_NO_FAT}"
      TARGET_CXXFLAGS+=" ${FLAGS_OPTIM_LTO_PARALLEL} ${FLAGS_OPTIM_LTO_NO_FAT}"
      TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_LTO_COMMON} ${FLAGS_OPTIM_LTO_PARALLEL}"
    elif flag_enabled "lto-fat" "no"; then
      TARGET_CFLAGS+=" ${FLAGS_OPTIM_LTO_NO_PARALLEL} ${FLAGS_OPTIM_LTO_FAT}"
      TARGET_CXXFLAGS+=" ${FLAGS_OPTIM_LTO_NO_PARALLEL} ${FLAGS_OPTIM_LTO_FAT}"
      TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_LTO_COMMON} ${FLAGS_OPTIM_LTO_NO_PARALLEL}"
    elif flag_enabled "lto" "no"; then
      TARGET_CFLAGS+=" ${FLAGS_OPTIM_LTO_NO_PARALLEL} ${FLAGS_OPTIM_LTO_NO_FAT}"
      TARGET_CXXFLAGS+=" ${FLAGS_OPTIM_LTO_NO_PARALLEL} ${FLAGS_OPTIM_LTO_NO_FAT}"
      TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_LTO_COMMON} ${FLAGS_OPTIM_LTO_NO_PARALLEL}"
    fi
  fi

  if flag_enabled "lto-off" "no"; then
    TARGET_CFLAGS+=" ${FLAGS_OPTIM_LTO_OFF}"
    TARGET_CXXFLAGS+=" ${FLAGS_OPTIM_LTO_OFF}"
    TARGET_LDFLAGS+=" ${FLAGS_OPTIM_LTO_OFF}"
  fi

  local linker="$(get_target_linker)"
  local linker_opts="LDFLAGS_OPTIM_LINKER_${linker^^}"

  TARGET_LDFLAGS+=" ${!linker_opts}"

  # compiler optimization, descending priority: speed, size, default
  if [ "${BUILD_WITH_DEBUG}" = "yes" ]; then
    if [ "${SPLIT_DEBUG_INFO}" = "yes" -a "${linker}" = "gold" ]; then
      TARGET_CFLAGS+=" ${CFLAGS_OPTIM_DEBUG_SPLIT}"
      TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_DEBUG_SPLIT}"
      TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_DEBUG_SPLIT}"
    else
      TARGET_CFLAGS+=" ${CFLAGS_OPTIM_DEBUG}"
      TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_DEBUG}"
      TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_DEBUG}"
    fi
  elif flag_enabled "speed" "no"; then
    TARGET_CFLAGS+=" ${CFLAGS_OPTIM_SPEED}"
    TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_SPEED}"
  elif flag_enabled "size" "no"; then
    TARGET_CFLAGS+=" ${CFLAGS_OPTIM_SIZE}"
    TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_SIZE}"
  else
    TARGET_CFLAGS+=" ${CFLAGS_OPTIM_DEFAULT}"
    TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_DEFAULT}"
  fi

  # position-independent code
  if flag_enabled "pic" "no"; then
    TARGET_CFLAGS+=" ${CFLAGS_OPTIM_PIC}"
    TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_PIC}"
    TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_PIC}"
  fi
  if flag_enabled "pic:host" "no"; then
    HOST_CFLAGS+=" ${CFLAGS_OPTIM_PIC}"
    HOST_CXXFLAGS+=" ${CXXFLAGS_OPTIM_PIC}"
    HOST_LDFLAGS+=" ${LDFLAGS_OPTIM_PIC}"
  fi

  # hardening support
  if flag_enabled "hardening" "${HARDENING_SUPPORT}"; then
    TARGET_CFLAGS+=" ${CFLAGS_OPTIM_HARDENING}"
    TARGET_CXXFLAGS+=" ${CXXFLAGS_OPTIM_HARDENING}"
    TARGET_CFLAGS+=" ${CPPFLAGS_OPTIM_HARDENING}"
    TARGET_LDFLAGS+=" ${LDFLAGS_OPTIM_HARDENING}"
  fi

  # parallel
  if flag_enabled "parallel" "yes"; then
    NINJA_OPTS="${NINJA_OPTS} -j${CONCURRENCY_MAKE_LEVEL}"
    export MAKEFLAGS="-j${CONCURRENCY_MAKE_LEVEL}"
  else
    NINJA_OPTS="${NINJA_OPTS} -j1"
    export MAKEFLAGS="-j1"
  fi

  # verbose flag
  if flag_enabled "verbose" "no"; then
    NINJA_OPTS="${NINJA_OPTS} -v"
    export MAKEFLAGS="${MAKEFLAGS} V=1 VERBOSE=1"
  fi

  case "$1:$2" in
    target:meson|init:meson)
      export DESTIMAGE="target"
      export AWK="gawk"
      export CC="${TOOLCHAIN}/bin/host-gcc"
      export CXX="${TOOLCHAIN}/bin/host-g++"
      export CPP="cpp"
      export LD="ld"
      export AS="as"
      export AR="ar"
      export NM="nm"
      export RANLIB="ranlib"
      export OBJCOPY="objcopy"
      export OBJDUMP="objdump"
      export STRIP="strip"
      export CPPFLAGS="${HOST_CPPFLAGS}"
      export CFLAGS="${HOST_CFLAGS}"
      export CXXFLAGS="${HOST_CXXFLAGS}"
      export LDFLAGS="${HOST_LDFLAGS}"
      setup_pkg_config_target
      export TARGET_CC="${TARGET_PREFIX}gcc"
      export TARGET_CXX="${TARGET_PREFIX}g++"
      export TARGET_AR="${TARGET_PREFIX}ar"
      export TARGET_STRIP="${TARGET_PREFIX}strip"
      export TARGET_CFLAGS="${TARGET_CFLAGS}"
      export TARGET_CXXFLAGS="${TARGET_CXXFLAGS}"
      export TARGET_LDFLAGS="${TARGET_LDFLAGS}"
      export HOST_CC="${CC}"
      export HOST_CXX="${CXX}"
      export HOSTCC="${CC}"
      export HOSTCXX="${CXX}"
      export CC_FOR_BUILD="${CC}"
      export CXX_FOR_BUILD="${CXX}"
      export BUILD_CC="${CC}"
      export BUILD_CXX="${CXX}"
      export _python_sysroot="${SYSROOT_PREFIX}"
      export _python_prefix=/usr
      export _python_exec_prefix=/usr
      ;;

    target:*|init:*)
      export DESTIMAGE="target"
      export CC="${TARGET_PREFIX}gcc"
      export CXX="${TARGET_PREFIX}g++"
      export CPP="${TARGET_PREFIX}cpp"
      export LD="${TARGET_PREFIX}ld"
      export AS="${TARGET_PREFIX}as"
      export AR="${TARGET_PREFIX}ar"
      export NM="${TARGET_PREFIX}nm"
      export RANLIB="${TARGET_PREFIX}ranlib"
      export OBJCOPY="${TARGET_PREFIX}objcopy"
      export OBJDUMP="${TARGET_PREFIX}objdump"
      export STRIP="${TARGET_PREFIX}strip"
      export CPPFLAGS="${TARGET_CPPFLAGS}"
      export CFLAGS="${TARGET_CFLAGS}"
      export CXXFLAGS="${TARGET_CXXFLAGS}"
      export LDFLAGS="${TARGET_LDFLAGS}"
      setup_pkg_config_target
      export CMAKE_CONF=${TOOLCHAIN}/etc/cmake-${TARGET_NAME}.conf
      export CMAKE="cmake -DCMAKE_TOOLCHAIN_FILE=${CMAKE_CONF} -DCMAKE_INSTALL_PREFIX=/usr"
      if [ ! -f ${CMAKE_CONF} ] ; then
        mkdir -p ${TOOLCHAIN}/etc
        echo "SET(CMAKE_SYSTEM_NAME Linux)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_SYSTEM_VERSION 1)"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_SYSTEM_PROCESSOR  ${TARGET_ARCH})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_C_COMPILER   ${CC})"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_CXX_COMPILER ${CXX})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_CPP_COMPILER $CPP)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_ASM_FLAGS_MINSIZEREL -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_CXX_FLAGS_MINSIZEREL -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_C_FLAGS_MINSIZEREL -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH  ${SYSROOT_PREFIX})"   >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)"  >> ${CMAKE_CONF}
        if [ "${DISPLAYSERVER}" = "x11" ]; then
          if [ "${OPENGL}" = "mesa" ] || listcontains "${GRAPHIC_DRIVERS}" "nvidia"; then
            echo "SET(OpenGL_GL_PREFERENCE GLVND)" >> ${CMAKE_CONF}
          fi
        fi
      fi
      export HOST_CC="${TOOLCHAIN}/bin/host-gcc"
      export HOST_CXX="${TOOLCHAIN}/bin/host-g++"
      export HOSTCC="${HOST_CC}"
      export HOSTCXX="${HOST_CXX}"
      export CC_FOR_BUILD="${HOST_CC}"
      export CXX_FOR_BUILD="${HOST_CXX}"
      export BUILD_CC="${HOST_CC}"
      export BUILD_CXX="${HOST_CXX}"
      export _python_sysroot="${SYSROOT_PREFIX}"
      export _python_prefix=/usr
      export _python_exec_prefix=/usr

      # rust
      export CARGO_TARGET_DIR="${PKG_BUILD}/.${TARGET_NAME}/target"
      export CARGO_HOME="$(get_build_dir rust)/cargo_home"
      export RUST_TARGET_PATH="${TOOLCHAIN}/lib/rustlib/"
      ;;

    host:*|bootstrap:*)
      export DESTIMAGE="host"
      export AWK="gawk"
      if [ "$1" = "host" ] && flag_enabled "local-cc" "no"; then
        export CC="${LOCAL_CC}"
        export CXX="${LOCAL_CXX}"
        if [ -n "${LOCAL_CCACHE}" ]; then
          export CCACHE_DIR="${LOCAL_CCACHE_DIR}"
          export CC="${LOCAL_CCACHE} ${CC}";
          export CXX="${LOCAL_CCACHE} ${CXX}";
        fi
      else
        export CC="${TOOLCHAIN}/bin/host-gcc"
        export CXX="${TOOLCHAIN}/bin/host-g++"
      fi
      export CPP="cpp"
      export LD="ld"
      export AS="as"
      export AR="ar"
      export NM="nm"
      export RANLIB="ranlib"
      export OBJCOPY="objcopy"
      export OBJDUMP="objdump"
      export STRIP="strip"
      export CPPFLAGS="${HOST_CPPFLAGS}"
      export CFLAGS="${HOST_CFLAGS}"
      export CXXFLAGS="${HOST_CXXFLAGS}"
      export LDFLAGS="${HOST_LDFLAGS}"
      setup_pkg_config_host
      export CMAKE_CONF=${TOOLCHAIN}/etc/cmake-${HOST_NAME}.conf
      export CMAKE="cmake -DCMAKE_TOOLCHAIN_FILE=${CMAKE_CONF} -DCMAKE_INSTALL_PREFIX=${TOOLCHAIN}"
      if [ ! -f ${CMAKE_CONF} ] ; then
        mkdir -p ${TOOLCHAIN}/etc
        echo "SET(CMAKE_SYSTEM_NAME Linux)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_SYSTEM_VERSION 1)"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_SYSTEM_PROCESSOR ${MACHINE_HARDWARE_NAME})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_C_COMPILER   ${CC})"  >> ${CMAKE_CONF}
        echo "SET(CMAKE_CXX_COMPILER ${CXX})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_CPP_COMPILER ${CXX})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_ASM_FLAGS_RELEASE -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_CXX_FLAGS_RELEASE -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_C_FLAGS_RELEASE -DDUMMYOPT)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_AR ${AR} CACHE FILEPATH "Archiver")" >> ${CMAKE_CONF} # hum?
        echo "SET(CMAKE_FIND_ROOT_PATH  ${TOOLCHAIN})" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM BOTH)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY BOTH)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE BOTH)" >> ${CMAKE_CONF}
        echo "SET(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE BOTH)" >> ${CMAKE_CONF}
      fi
      export HOST_CC="${CC}"
      export HOST_CXX="${CXX}"
      export HOSTCC="${CC}"
      export HOSTCXX="${CXX}"
      export CC_FOR_BUILD="${CC}"
      export CXX_FOR_BUILD="${CXX}"
      export BUILD_CC="${CC}"
      export BUILD_CXX="${CXX}"
      export _python_sysroot="${TOOLCHAIN}"
      export _python_prefix=/
      export _python_exec_prefix=/

      # rust
      case "${MACHINE_HARDWARE_NAME}" in
        "arm")
          RUST_HOST="arm-unknown-linux-gnueabihf"
          ;;
        "aarch64")
          RUST_HOST="aarch64-unknown-linux-gnu"
          ;;
        "x86_64")
          RUST_HOST="x86_64-unknown-linux-gnu"
          ;;
        "i686")
          RUST_HOST="i686-unknown-linux-gnu"
          ;;
      esac

      export CARGO_TARGET_DIR="${PKG_BUILD}/.${RUST_HOST}/target"
      export CARGO_HOME="$(get_build_dir rust)/cargo_home"
      export RUST_TARGET_PATH="${TOOLCHAIN}/lib/rustlib/"
      ;;
  esac
}

create_meson_conf_host() {
  local properties
  properties="PKG_MESON_PROPERTIES_${1^^}"
  cat > $2 <<EOF
[binaries]
c = '${CC}'
cpp = '${CXX}'
ar = '${AR}'
strip = '${STRIP}'
pkgconfig = '${PKG_CONFIG}'
llvm-config = '${TOOLCHAIN}/bin/llvm-config'

[host_machine]
system = 'linux'
cpu_family = '${TARGET_ARCH}'
cpu = '${TARGET_SUBARCH}'
endian = 'little'

[built-in options]
$(python3 -c "import os; print('c_args = {}'.format([x for x in os.getenv('CFLAGS').split()]))")
$(python3 -c "import os; print('c_link_args = {}'.format([x for x in os.getenv('LDFLAGS').split()]))")
$(python3 -c "import os; print('cpp_args = {}'.format([x for x in os.getenv('CXXFLAGS').split()]))")
$(python3 -c "import os; print('cpp_link_args = {}'.format([x for x in os.getenv('LDFLAGS').split()]))")

[properties]
root = '${TOOLCHAIN}'
${!properties}
EOF
}

create_meson_conf_target() {
  local properties
  properties="PKG_MESON_PROPERTIES_${1^^}"

  cat > $2 <<EOF
[binaries]
c = '${TARGET_CC}'
cpp = '${TARGET_CXX}'
ar = '${TARGET_AR}'
strip = '${TARGET_STRIP}'
pkgconfig = '${PKG_CONFIG}'
llvm-config = '${SYSROOT_PREFIX}/usr/bin/llvm-config'
libgcrypt-config = '${SYSROOT_PREFIX}/usr/bin/libgcrypt-config'

[build_machine]
system = 'linux'
cpu_family = '${MACHINE_HARDWARE_NAME}'
cpu = '${MACHINE_HARDWARE_CPU}'
endian = 'little'

[host_machine]
system = 'linux'
cpu_family = '${TARGET_ARCH}'
cpu = '${TARGET_SUBARCH}'
endian = 'little'

[built-in options]
$(python3 -c "import os; print('c_args = {}'.format([x for x in os.getenv('TARGET_CFLAGS').split()]))")
$(python3 -c "import os; print('c_link_args = {}'.format([x for x in os.getenv('TARGET_LDFLAGS').split()]))")
$(python3 -c "import os; print('cpp_args = {}'.format([x for x in os.getenv('TARGET_CXXFLAGS').split()]))")
$(python3 -c "import os; print('cpp_link_args = {}'.format([x for x in os.getenv('TARGET_LDFLAGS').split()]))")

[properties]
needs_exe_wrapper = true
root = '${SYSROOT_PREFIX}/usr'
${!properties}
EOF
}

# unset all PKG_* vars apart from those exported by setup_toolchain, then set default values
reset_pkg_vars() {
  local vars var

  for var in ${!PKG_*}; do
    if [ "${var}" = "PKG_CONFIG" ] || \
       [ "${var}" = "PKG_CONFIG_PATH" ] || \
       [ "${var}" = "PKG_CONFIG_LIBDIR" ] || \
       [ "${var}" = "PKG_CONFIG_SYSROOT_DIR" ] || \
       [ "${var}" = "PKG_CONFIG_ALLOW_SYSTEM_CFLAGS" ] || \
       [ "${var}" = "PKG_CONFIG_ALLOW_SYSTEM_LIBS" ]; then
       continue
    fi
    vars+="${var} "
  done
  [ -n "${vars}" ] && unset -v ${vars}

  PKG_VERSION="0.0invalid"
  PKG_REV="0"
  PKG_ARCH="any"
  PKG_LICENSE="unknown"
  PKG_TOOLCHAIN="auto"
  PKG_IS_ADDON="no"
  PKG_PYTHON_VERSION="${DEFAULT_PYTHON_VERSION}"
}

set_debug_depends() {
  local pkg dep_pkg map tmp_array mpkg bpkg kvpair

  _DEBUG_DEPENDS_LIST=""
  _DEBUG_PACKAGE_LIST=""
  if [ "${DEBUG:-no}" != "no" ]; then
    # Convert DEBUG_GROUPS into array of groups, adding "all" if required
    declare -A debug_group_map
    for kvpair in ${DEBUG_GROUPS}; do
      debug_group_map+=(["${kvpair%=*}"]="${kvpair#*=}")
    done
    [ -z "${debug_group_map["all"]}" ] && debug_group_map+=(["all"]="all")

    # Expand $DEBUG into $_DEBUG_PACKAGE_LIST
    for pkg in ${DEBUG//,/ }; do
      [ "${pkg}" = "yes" ] && pkg="${DEBUG_GROUP_YES:-all}"
      map="${debug_group_map["${pkg}"]}"
      [ -z "${map}" ] && map="${pkg}"
      for mpkg in ${map//,/ }; do
        [[ ${mpkg} =~ ^[!-] ]] && bpkg="${mpkg:1}" || bpkg="${mpkg}"
        [[ ${bpkg} =~ \+$ ]] && bpkg="${bpkg::-1}"
        # Remove existing instances of this package
        listcontains "${_DEBUG_PACKAGE_LIST}" "[!-]?${bpkg}[+]?" && _DEBUG_PACKAGE_LIST="$(listremoveitem "${_DEBUG_PACKAGE_LIST}" "[!-]?${bpkg}[+]?")"
        # Add package
        _DEBUG_PACKAGE_LIST+=" ${mpkg}"
      done
    done
    # Use array word splitting to squash spaces
    tmp_array=(${_DEBUG_PACKAGE_LIST})
    _DEBUG_PACKAGE_LIST="${tmp_array[@]}"

    # Determine dependencies for each package+
    for pkg in ${_DEBUG_PACKAGE_LIST}; do
      if [ "${pkg}" != "all" ] && [[ ! ${pkg} =~ ^[!-] ]]; then
        ! listcontains "${_DEBUG_DEPENDS_LIST}" "${pkg}" && _DEBUG_DEPENDS_LIST+=" ${pkg}"
        [[ ! ${pkg} =~ \+$ ]] && continue
        for dep_pkg in $(get_pkg_variable ${pkg::-1} PKG_DEPENDS_TARGET); do
          [ "${dep_pkg}" = "toolchain" ] && continue
          [[ ${dep_pkg} =~ ^.*:host$ ]] && continue
          ! listcontains "${_DEBUG_DEPENDS_LIST}" "${dep_pkg}" && _DEBUG_DEPENDS_LIST+=" ${dep_pkg}"
        done
      fi
    done
    tmp_array=(${_DEBUG_DEPENDS_LIST})
    _DEBUG_DEPENDS_LIST="${tmp_array[@]}"
  fi
  export _DEBUG_DEPENDS_LIST _DEBUG_PACKAGE_LIST
}

# Return 0 if building with debug is enabled for the current package (or all packages).
# Examples: DEBUG=yes  DEBUG=all  DEBUG='all,!linux'  DEBUG=kodi  DEBUG=kodi,samba
build_with_debug() {
  if [ "${DEBUG:-no}" != "no" -a -n "${PKG_NAME}" -a -n "${_DEBUG_DEPENDS_LIST+x}" ]; then
    # Return 1 if this package is not to be built with debug
    listcontains "${_DEBUG_PACKAGE_LIST}" "[!-]${PKG_NAME}[+]?" && return 1

    # Build all packages with debug
    listcontains "${_DEBUG_PACKAGE_LIST}" "all" && return 0

    # Debugging is enabled for at least one package, so enable debug in the "debug" virtual package
    [ "${PKG_NAME}" = "debug" ] && return 0

    # Build addons with debug if we're building the mediacenter with debug and with dependencies
    [ "${PKG_IS_ADDON}" = "yes" -o "${PKG_IS_ADDON}" = "embedded" ] && listcontains "${_DEBUG_DEPENDS_LIST}" "${MEDIACENTER}\+" && return 0

    # Build kernel packages with debug if we're building the kernel with debug and with dependencies
    [ "${PKG_IS_KERNEL_PKG}" = "yes" ] && listcontains "${_DEBUG_DEPENDS_LIST}" "linux\+" && return 0

    # Build this package with debug if it's a resolved dependency
    listcontains "${_DEBUG_DEPENDS_LIST}" "${PKG_NAME}" && return 0
  fi

  return 1
}

# strip
debug_strip() {
  if [ -z "${BUILD_WITH_DEBUG}" ]; then
    die "ERROR: debug_strip() must not be called without configuring BUILD_WITH_DEBUG"
  fi

  if [ "${BUILD_WITH_DEBUG}" != "yes" ] && flag_enabled "strip" "yes"; then
    find $* -type f \( -executable ! -iname "*.AppImage" \) | xargs ${STRIP} 2>/dev/null || :
  fi
}

init_package_cache() {
  local _ANCHOR="@?+?@"
  local temp_global temp_local

  # If the package caches are unset, then populate them
  if [ -z "${_CACHE_PACKAGE_GLOBAL}" -o -z "${_CACHE_PACKAGE_LOCAL}" -o -z "${_CACHE_PACKAGE_DEVICE}" ]; then
    temp_global="$(mktemp)"
    temp_local="$(mktemp)"
    temp_device="$(mktemp)"

    # cache packages folder
    find "${ROOT}/${PACKAGES}" -type f -name package.mk 2>/dev/null | sed "s#/package\.mk\$#${_ANCHOR}#" >> "${temp_global}"

    # cache project folder for packages
    find "${ROOT}/projects/${PROJECT}/packages" -type f -name package.mk 2>/dev/null | sed "s#/package\.mk\$#${_ANCHOR}#" >> "${temp_local}"

    # cache project/device folder for packages
    if [ -n "${DEVICE}" ]; then
      find "${ROOT}/projects/${PROJECT}/devices/${DEVICE}/packages" -type f -name package.mk 2>/dev/null | sed "s#/package\.mk\$#${_ANCHOR}#" >> "${temp_device}"
    fi

    _CACHE_PACKAGE_GLOBAL="${BUILD}/.cache_package_global"
    _CACHE_PACKAGE_LOCAL="${BUILD}/.cache_package_local"
    _CACHE_PACKAGE_DEVICE="${BUILD}/.cache_package_device"

    export _CACHE_PACKAGE_LOCAL _CACHE_PACKAGE_GLOBAL _CACHE_PACKAGE_DEVICE

    # overwrite existing cache files only when they are invalid, or not yet created
    # Order should be largest to smallest...

    mkdir -p "$(dirname "${_CACHE_PACKAGE_GLOBAL}")"
    if [ -f "${_CACHE_PACKAGE_GLOBAL}" ] && cmp -s "${temp_global}" "${_CACHE_PACKAGE_GLOBAL}"; then
      rm "${temp_global}"
    else
      mv "${temp_global}" "${_CACHE_PACKAGE_GLOBAL}"
    fi

    if [ -f "${_CACHE_PACKAGE_LOCAL}" ] && cmp -s "${temp_local}" "${_CACHE_PACKAGE_LOCAL}"; then
      rm "${temp_local}"
    else
      mv "${temp_local}" "${_CACHE_PACKAGE_LOCAL}"
    fi

    if [ -f "${_CACHE_PACKAGE_DEVICE}" ] && cmp -s "${temp_device}" "${_CACHE_PACKAGE_DEVICE}"; then
      rm "${temp_device}"
    else
      mv "${temp_device}" "${_CACHE_PACKAGE_DEVICE}"
    fi

  fi

  if [ -z "${_DEBUG_DEPENDS_LIST+x}" ]; then
    set_debug_depends
  fi
}

load_build_config() {
  if [ -d "${1}" -a -f ${1}/.build.conf ]; then
    source ${1}/.build.conf
    return 0
  fi
  return 1
}

save_build_config() {
  local var
  mkdir -p ${BUILD}
  rm -f ${BUILD}/.build.conf
  for var in PROJECT DEVICE ARCH DEBUG BUILD_SUFFIX; do
    echo "export ${var}=\"${!var}\"" >> ${BUILD}/.build.conf
  done
}

check_path() {
  local dashes="===========================" path_err_msg
  if [ "${PWD##/usr}" != "${PWD}" ]; then
    path_err_msg="\n ${dashes}${dashes}${dashes}"
    path_err_msg="${path_err_msg}\n ERROR: Detected building inside /usr"
    path_err_msg="${path_err_msg}\n ${dashes}${dashes}${dashes}"
    path_err_msg="${path_err_msg}\n This is not supported with our buildsystem."
    path_err_msg="${path_err_msg}\n Please use another dir (for example your \$HOME) to build ${DISTRONAME}"

    die "${path_err_msg}"
  fi
}

check_distro() {
  local dashes="===========================" distro_err_msg
  if [ -z "${DISTRO}" -o ! -d "${DISTRO_DIR}/${DISTRO}" ]; then
    distro_err_msg="\n ${dashes}${dashes}${dashes}"
    distro_err_msg="${distro_err_msg}\n ERROR: Distro not found, use a valid distro or create a new config"
    distro_err_msg="${distro_err_msg}\n ${dashes}${dashes}${dashes}"
    distro_err_msg="${distro_err_msg}\n\n Valid distros:"

    for distros in ${DISTRO_DIR}/*; do
      distro_err_msg="${distro_err_msg}\n - ${distros##*/}"
    done
    die "${distro_err_msg}"
  fi
}

check_project() {
  local dashes="===========================" project_err_msg
  if [ -z "${PROJECT}" -o ! -d "${PROJECT_DIR}/${PROJECT}" ]; then
    project_err_msg="\n ${dashes}${dashes}${dashes}"
    project_err_msg="${project_err_msg}\n ERROR: Project not found, use a valid project or create a new config"
    project_err_msg="${project_err_msg}\n ${dashes}${dashes}${dashes}"
    project_err_msg="${project_err_msg}\n\n Valid projects:"

    for projects in ${PROJECT_DIR}/*; do
      project_err_msg="${project_err_msg}\n - ${projects##*/}"
    done
    die "${project_err_msg}"
  fi
}

check_device() {
  local dashes="===========================" device_err_msg
  if [ \( -z "${DEVICE}" -a -d "${PROJECT_DIR}/${PROJECT}/devices" \) -o \
       \( -n "${DEVICE}" -a ! -d "${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}" \) ]; then
    device_err_msg="\n ${dashes}${dashes}${dashes}"
    device_err_msg="${device_err_msg}\n ERROR: You need to specify a valid device for the ${PROJECT} project"
    device_err_msg="${device_err_msg}\n ${dashes}${dashes}${dashes}"
    device_err_msg="${device_err_msg}\n\n Valid devices for project: ${PROJECT}"

    for device in ${PROJECT_DIR}/${PROJECT}/devices/*; do
      device_err_msg="${device_err_msg}\n - ${device##*/}"
    done
    die "${device_err_msg}"
  fi
}

check_arch() {
  local dashes="===========================" arch_err_msg linux_config_dir
  if [ -d "${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/linux" ]; then
    linux_config_dir="${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/linux"
  else
    linux_config_dir="${PROJECT_DIR}/${PROJECT}/linux"
  fi

  if [ ! -e "${linux_config_dir}/linux.${TARGET_PATCH_ARCH:-${TARGET_ARCH}}.conf" ] &&
       ! ls "${linux_config_dir}/"*/linux.${TARGET_PATCH_ARCH:-${TARGET_ARCH}}.conf &>/dev/null; then
    arch_err_msg="\n ${dashes}${dashes}${dashes}"
    arch_err_msg="${arch_err_msg}\n ERROR: Architecture not found, use a valid Architecture"
    arch_err_msg="${arch_err_msg}\n for your project or create a new config"
    arch_err_msg="${arch_err_msg}\n ${dashes}${dashes}${dashes}"
    arch_err_msg="${arch_err_msg}\n\n Valid Architectures for your project: ${PROJECT}"

    for arch in ${linux_config_dir}/*.conf ${linux_config_dir}/*/linux.${TARGET_ARCH}.conf; do
      [[ ${arch} =~ .*\*.* ]] && continue #ignore unexpanded wildcard
      arch_err_msg="${arch_err_msg}\n - $(basename ${arch} | cut -f2 -d".")"
    done
    die "${arch_err_msg}"
  fi
}

check_config() {
  check_path
  check_distro
  check_project
  check_device
  check_arch
}

do_autoreconf() {
  export ACLOCAL_DIR=${SYSROOT_PREFIX}/usr/share/aclocal

  if [ -e "${TOOLCHAIN}/bin/autoconf" ]; then
    export AUTOCONF=${TOOLCHAIN}/bin/autoconf
  fi

  if [ -e "${TOOLCHAIN}/bin/automake" ]; then
    export AUTOMAKE=${TOOLCHAIN}/bin/automake
  fi

  if [ -e "${TOOLCHAIN}/bin/autopoint" ]; then
    export AUTOPOINT=${TOOLCHAIN}/bin/autopoint
  fi

  if [ -e "${TOOLCHAIN}/bin/libtoolize" ]; then
    export LIBTOOLIZE=${TOOLCHAIN}/bin/libtoolize
  fi

  # >autoconf-2.69 will call gtkdocize when used in macros
  # when called with --install parameter.
  # use "true" unless gtkdocsize is in the toolchain.
  if [ -e "${TOOLCHAIN}/bin/gtkdocize" ]; then
    export GTKDOCIZE=${TOOLCHAIN}/bin/gtkdocize
  else
    export GTKDOCIZE=true
  fi

  if [ -e "${TOOLCHAIN}/bin/intltoolize" ]; then
    export INTLTOOLIZE=${TOOLCHAIN}/bin/intltoolize
  fi

  if [ -e "${TOOLCHAIN}/bin/aclocal" ]; then
    export ACLOCAL="${TOOLCHAIN}/bin/aclocal -I ${ACLOCAL_DIR}"
  fi

  if [ -e "${TOOLCHAIN}/bin/autoheader" ]; then
    export AUTOHEADER=${TOOLCHAIN}/bin/autoheader
  fi

  if [ -e "${TOOLCHAIN}/bin/libtool" ]; then
    export LIBTOOL=${TOOLCHAIN}/bin/libtool
  fi

  if [ -e "${TOOLCHAIN}/bin/autoreconf" -a -e "${INTLTOOLIZE}" ]; then
    mkdir -p ${ACLOCAL_DIR}
    if [ -e "${LIBTOOLIZE}" ]; then
      export AUTORECONF="${TOOLCHAIN}/bin/autoreconf --verbose --force --install -I ${ACLOCAL_DIR}"
    else
      export AUTORECONF="${TOOLCHAIN}/bin/autoreconf --verbose --force -I ${ACLOCAL_DIR}"
    fi
    ${AUTORECONF} $@
  fi
}

# arg1: filename (libtool) to remove hardcode rpath when --disable-rpath is not supported by configure
libtool_remove_rpath() {
  sed -i 's|^hardcode_libdir_flag_spec=.*|hardcode_libdir_flag_spec=""|g' ${1}
  sed -i 's|^runpath_var=LD_RUN_PATH|runpath_var=DIE_RPATH_DIE|g' ${1}
}

### PACKAGE HELPERS ###
# get variable ($2) for package ($1).
# avoid infinite recursion if required package is already loaded.
get_pkg_variable() {
  if [ -n "$1" -a -n "$2" ] ; then
    if [ "$1" != "${PKG_NAME}" ]; then
      source_package "${1}"
    fi
    echo "${!2}"
  fi
}

# get package's build dir
get_build_dir() {
  local _PKG_NAME="${1%:*}" _PKG_VERSION="$(get_pkg_version "$1")"
  if [ -n "${_PKG_NAME}" -a -n "${_PKG_VERSION}" ]; then
    echo $BUILD/${_PKG_NAME}-${_PKG_VERSION}
  fi
}

get_pkg_version() {
  get_pkg_variable "$1" PKG_VERSION
}

get_pkg_version_maj_min() {
  local pkg_version

  [ -n "${1}" ] && pkg_version="$(get_pkg_version "${1}")" || pkg_version="${PKG_VERSION}"

  if [[ ${pkg_version} =~ ^[0-9A-Za-z]*\.[0-9A-Za-z]*\.[0-9A-za-z]*$ ]]; then
    echo "${pkg_version%.*}"
  elif [[ ${pkg_version} =~ ^[0-9A-Za-z]*\.[0-9A-Za-z]*$ ]]; then
    echo "${pkg_version}"
  else
    echo "${pkg_version}"
  fi
}

get_pkg_directory() {
  local _PKG_ROOT_NAME=${1%:*} _ALL_DIRS _FOUND=0 _ANCHOR="@?+?@" _PKG_DIR _DIR

  # Check for any available device package in preference to a local package
  for _DIR in $(grep -F "/${_PKG_ROOT_NAME}${_ANCHOR}" "${_CACHE_PACKAGE_DEVICE}"); do
    _DIR="${_DIR%${_ANCHOR}}"
    # found first, set ${_PKG_DIR}
    _PKG_DIR="$_DIR"
    # keep track of dirs with package.mk for detecting multiple folders
    _ALL_DIRS+="${_DIR}\n"
    _FOUND=$((_FOUND+1))
  done

  # Check for any available local package in preference to a global package
  if [ ${_FOUND} -eq 0 ]; then
    for _DIR in $(grep -F "/${_PKG_ROOT_NAME}${_ANCHOR}" "${_CACHE_PACKAGE_LOCAL}"); do
      _DIR="${_DIR%${_ANCHOR}}"
      # found first, set ${_PKG_DIR}
      _PKG_DIR="$_DIR"
      # keep track of dirs with package.mk for detecting multiple folders
      _ALL_DIRS+="${_DIR}\n"
      _FOUND=$((_FOUND+1))
    done
  fi

  # If there's no local package available, use the global package
  if [ ${_FOUND} -eq 0 ]; then
    for _DIR in $(grep -F "/${_PKG_ROOT_NAME}${_ANCHOR}" "${_CACHE_PACKAGE_GLOBAL}"); do
      _DIR="${_DIR%${_ANCHOR}}"
      # found first, set ${_PKG_DIR}
      _PKG_DIR="$_DIR"
      # keep track of dirs with package.mk for detecting multiple folders
      _ALL_DIRS+="${_DIR}\n"
      _FOUND=$((_FOUND+1))
    done
  fi

  # _FOUND multiple packages? fail
  if [ ${_FOUND} -gt 1 ]; then
    echo "Error - multiple package folders for package ${_PKG_ROOT_NAME}:" >&2
    echo -e "$_ALL_DIRS" >&2
    die
  fi

  echo "${_PKG_DIR}"
}

calculate_stamp() {
  local stamp data

  stamp="${PKG_DIR} ${PROJECT_DIR}/${PROJECT}/patches/${PKG_NAME}"
  [ -n "${DEVICE}" ] && stamp+=" ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/patches/${PKG_NAME}"
  [ -n "${PKG_NEED_UNPACK}" ] && stamp+=" ${PKG_NEED_UNPACK}"
  if [ -n "${PKG_STAMP_VAR}" ]; then
    local TMP_VAR="$(get_build_dir ${PKG_NAME})/.pkg_stamp_var"
    echo "${PKG_STAMP_VAR}" > ${TMP_VAR}
    stamp+=" ${TMP_VAR}"
  fi

  data="$(find ${stamp} -exec sha256sum {} \; 2>/dev/null | sed "s/ ${ROOT//\//\\/}\// /")"
  [ -n "${PKG_STAMP}" ] && data+=$'\n'"$(echo "${PKG_STAMP}" | sha256sum)"

  echo "${data}" | sort | sha256sum | cut -d" " -f1
}

target_has_feature() {
  listcontains "${TARGET_FEATURES}" "$1"
}

# configure variables for go
go_configure() {
  unset GOARCH GOARM
  case ${TARGET_ARCH} in
    x86_64)
      export GOARCH=amd64
      ;;
    arm)
      export GOARCH=arm

      case ${TARGET_CPU} in
        arm1176jzf-s)
          export GOARM=6
          ;;
        *)
          export GOARM=7
          ;;
      esac
      ;;
    aarch64)
      export GOARCH=arm64
      ;;
  esac

  export GOOS=linux
  export GOROOT=${TOOLCHAIN}/lib/golang
  export PATH=${PATH}:${GOROOT}/bin

  go_configure_path

  export CGO_ENABLED=1
  export CGO_NO_EMULATION=1
  export CGO_CFLAGS=${CFLAGS}
}

go_configure_path() {
  export GOLANG=${TOOLCHAIN}/lib/golang/bin/go
  export GOPATH=${PKG_BUILD}/.gopath
  export GOFLAGS="-modcacherw"
}

# find path for matching file or directory, searching standard directory hierarchy, using optional default
# if a path is located it will be set in FOUND_PATH and exit code will be 0.
find_path() {
  local test_func="$1" search="$2" default="$3"
  local dir match wildcard=0 ftype

  # support wildcard matches
  [[ ${search} =~ \* || ${search} =~ \? ]] && wildcard=1

  [ "${test_func}" = "-f" ] && ftype="file" || ftype="dir"

  for dir in ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/packages/${PKG_NAME} \
             ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE} \
             ${PROJECT_DIR}/${PROJECT}/packages/${PKG_NAME} \
             ${PROJECT_DIR}/${PROJECT} \
             ${DISTRO_DIR}/${DISTRO}/packages/${PKG_NAME} \
             ${DISTRO_DIR}/${DISTRO} \
             ${PKG_DIR} \
             ; do
    # ignore directories with missing DEVICE or PKG_NAME components
    [[ ${dir} =~ /packages/$ ]] && continue
    [[ ${dir} =~ /devices/$ ]] && continue
    [[ ${dir} =~ /devices//packages/${PKG_NAME}$ ]] && continue

    if [ ${wildcard} -eq 1 ]; then
      ls ${dir}/${search} 1>/dev/null 2>&1 && match="${dir}/${search}" && break
    else
      [ ${test_func} "${dir}/${search}" ] && match="${dir}/${search}" && break
    fi
  done

  if [ -z "${match}" -a -n "${default}" ]; then
    if [[ ${default} =~ \* || ${default} =~ \? ]]; then
      ls ${default} 1>/dev/null 2>&1 && match="${default}"
    else
      [ ${test_func} "${default}" ] && match="${default}"
    fi
  fi

  if [ -n "${match}" ]; then
    FOUND_PATH="${match}"
    [ "${VERBOSE_FIND_PATH,,}" = "yes" ] && echo "find_path: Searching for ${ftype}: \"${search}\", found: \"$FOUND_PATH\"" >&2
    return 0
  else
    unset FOUND_PATH
    [ "${VERBOSE_FIND_PATH,,}" = "yes" ] && echo "find_path: Searching for ${ftype}: \"${search}\" - not found" >&2
    return 1
  fi
}

find_file_path() {
  find_path -f "$1" "$2"
}

find_dir_path() {
  find_path -d "$1" "$2"
}

# p1: name of function to test for
# return 0 if function exists, 1 if not
pkg_call_exists() {
  PKG_CURRENT_CALL="${1}"
  if [ "$(type -t ${1})" = "function" ]; then
    PKG_CURRENT_CALL_TYPE="package.mk"
    return 0
  else
    PKG_CURRENT_CALL_TYPE="default"
    return 1
  fi
}

# Optional variant of pkg_call_exists()
# Clear PKG_CURRENT_CALL when function is not implemented.
pkg_call_exists_opt() {
  if pkg_call_exists $1; then
    return 0
  else
    pkg_call_finish
    return 1
  fi
}

# Function to be called is set by pkg_call_exists/pkg_call_exists_opt
# Args: whatever the called function expects
# testing the exit code value of this function is likely to break set -e fail-on-error behaviour
pkg_call() {
  [ -n "${PKG_CURRENT_CALL}" ] || die "$(print_color CLR_ERROR "PKG_CURRENT_CALL is not set!")"
  [ -n "${PKG_NAME}" ] || die "$(print_color CLR_ERROR "FAILURE: Cannot call ${PKG_CURRENT_CALL} package function when package is not known!")"

  ${PKG_CURRENT_CALL} "${@}"
  pkg_call_finish
}

pkg_call_finish() {
  PKG_CURRENT_CALL=""
}

unset_functions() {
  local target

  unset -f configure_package

  unset -f pre_unpack unpack post_unpack pre_get
  unset -f pre_patch post_patch

  for target in target host init bootstrap; do
    unset -f pre_build_${target}
    unset -f pre_configure_${target} configure_${target} post_configure_${target}
    unset -f pre_make_${target} make_${target} post_make_${target}
    unset -f pre_makeinstall_${target} makeinstall_${target} post_makeinstall_${target}
  done

  unset -f pre_install post_install

  unset -f addon
}

# p1: name of package to be sourced
source_package() {
  local opwd="${PWD}"

  # Don't use BUILD_WITH_DEBUG in "global" package.mk - instead, call the function
  # build_with_debug() directly as the function depends on various package.mk
  # variables that will be in the process of being configured. Once package.mk is
  # fully sourced we can set this variable and use it in situations where we know the
  # package has already been sourced.
  unset BUILD_WITH_DEBUG

  reset_pkg_vars
  unset_functions

  if [ -n "${1}" ]; then
    [ -f "${1}" ] && PKG_DIR="$(dirname "${1}")" || PKG_DIR="$(get_pkg_directory "${1}")"

    [ -n "${PKG_DIR}" -a -r ${PKG_DIR}/package.mk ] || die "FAILURE: unable to source package - ${1}/package.mk does not exist"

    cd "${ROOT}"
    . ${PKG_DIR}/package.mk || die "FAILURE: an error occurred while sourcing ${PKG_DIR}/package.mk"
    cd "${opwd}"

    PKG_SHORTDESC="${PKG_SHORTDESC:-${PKG_NAME} (autogenerated)}"
    PKG_LONGDESC="${PKG_LONGDESC:-${PKG_NAME} (autogenerated)}"

    if [ "${PKG_IS_ADDON}" = "yes" -o "${PKG_IS_ADDON}" = "embedded" ] ; then
      [ -z $PKG_SECTION ] && PKG_ADDON_ID="${PKG_NAME}" || PKG_ADDON_ID="${PKG_SECTION//\//.}.${PKG_NAME}"
      [ "${PKG_ADDON_IS_STANDALONE}" != "yes" ] && PKG_NEED_UNPACK="${PKG_NEED_UNPACK} $(get_pkg_directory ${MEDIACENTER})"
    fi

    if [ -n "${PKG_DEPENDS_UNPACK}" ]; then
      for _p in ${PKG_DEPENDS_UNPACK}; do
        PKG_NEED_UNPACK+=" $(get_pkg_directory ${_p})"
      done
    fi

    # Automatically set PKG_SOURCE_NAME unless it is already defined.
    # PKG_SOURCE_NAME will be automatically set to a name based on
    # the ${PKG_NAME}-${PKG_VERSION} convention.
    #
    # Any ${PKG_URL} that references more than a single url will abort
    # the build as these are no longer supported - use mkpkg instead.
    if [ -n "${PKG_URL}" -a -z "${PKG_SOURCE_NAME}" ]; then
      if [[ ${PKG_URL} =~ .*\ .* ]]; then
        echo "Error - packages with multiple urls are no longer supported, use mkpkg."
        echo "${PKG_URL}"
        die
      fi
      if [[ ${PKG_URL} =~ .git$ || ${PKG_URL} =~ ^git:// ]]; then
        PKG_SOURCE_NAME=${PKG_NAME}-${PKG_VERSION}
      elif [[ ${PKG_URL} =~ ^file:// ]]; then
        PKG_SOURCE_NAME=${PKG_URL#file://}
        # if no specific PKG_TAR_COPY_OPTS then default to excluding .git and .svn as they can be huge
        [ -z "${PKG_TAR_COPY_OPTS+x}" ] && PKG_TAR_COPY_OPTS="--exclude=.git --exclude=.svn"
      else
        PKG_SOURCE_NAME="${PKG_URL##*/}"
        case ${PKG_SOURCE_NAME} in
          ${PKG_NAME}-${PKG_VERSION}.*)
            PKG_SOURCE_NAME=${PKG_SOURCE_NAME}
            ;;
          *.tar | *.tbz | *.tgz | *.txz | *.7z | *.zip)
            PKG_SOURCE_NAME=${PKG_NAME}-${PKG_VERSION}.${PKG_SOURCE_NAME##*\.}
            ;;
          *.tar.bz2 | *.tar.gz | *.tar.xz)
            PKG_SOURCE_NAME=${PKG_NAME}-${PKG_VERSION}.tar.${PKG_SOURCE_NAME##*\.}
            ;;
          *.diff | *.patch | *.diff.bz2 | *.patch.bz2 | patch-*.bz2 | *.diff.gz | *.patch.gz | patch-*.gz)
            PKG_SOURCE_NAME=${PKG_SOURCE_NAME}
            ;;
          *)
            PKG_SOURCE_NAME=${PKG_NAME}-${PKG_VERSION}.${PKG_SOURCE_NAME##*\.}
            ;;
        esac
      fi
    fi

    PKG_BUILD="$BUILD/${PKG_NAME}-${PKG_VERSION}"
  fi

  build_with_debug && BUILD_WITH_DEBUG="yes" || BUILD_WITH_DEBUG="no"

  # Late variable binding - allow the package to now evaluate any variables
  # that we may have initialised after sourcing the package, typically
  # PKG_BUILD etc.
  if [ -n "${PKG_NAME}" ]; then
    if pkg_call_exists configure_package; then
      pkg_call configure_package
    fi
  fi
}

# arg1: file, or directory to recursively compile.
python_compile() {
  local path="${1:-${INSTALL}/usr/lib/${PKG_PYTHON_VERSION}}"
  ${TOOLCHAIN}/bin/python3 -Wi -t -B ${TOOLCHAIN}/lib/${PKG_PYTHON_VERSION}/compileall.py -f -d "${path#${INSTALL}}" "${path}"
  python_remove_source "${path}"
}

# arg1: file, or directory from which to recursively remove all py source code
python_remove_source() {
  local path="${1:-${INSTALL}/usr/lib/${PKG_PYTHON_VERSION}}"
  if [ -d "${path}" ]; then
    find "${path}" -type f -name '*.py' -delete
  else
    rm -f "${path}"
  fi
}

# arg1: directory to process recursively
# strip incorrect build-host ABI from native Python3 modules (see PEP3149)
python_fix_abi() {
  local pymodule pyname

  for pymodule in $(find ${1} -type f -name '*.cpython-*.so' 2>/dev/null); do
    pyname=${pymodule##*/}
    pyname=${pyname%.so} # strip extension
    pyname=${pyname%.*}  # strip incorrect ABI
    echo "python_fix_abi: Removing ABI from ${pymodule} -> ${pyname}.so"
    mv ${pymodule} ${pymodule%/*}/${pyname}.so
  done
}

### KERNEL HELPERS ###
kernel_path() {
  get_build_dir linux
}

kernel_version() {
  get_pkg_version linux
}

kernel_config_path() {
  local cfg pkg_linux_dir pkg_linux_version config_name

  pkg_linux_version="$(get_pkg_version linux)"
  pkg_linux_dir="$(get_pkg_directory linux)"

  config_name="linux.${TARGET_PATCH_ARCH:-${TARGET_ARCH}}.conf"

  for cfg in ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/linux/${pkg_linux_version}/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/linux/${LINUX}/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/linux/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/linux/${pkg_linux_version}/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/linux/${LINUX}/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/linux/${config_name} \
             ${pkg_linux_dir}/config/${pkg_linux_version}/${config_name} \
             ${pkg_linux_dir}/config/${LINUX}/${config_name} \
             ${pkg_linux_dir}/config/${config_name} \
             ; do
    [[ ${cfg} =~ /devices//linux/ ]] && continue
    [ -f "${cfg}" ] && echo "${cfg}" && return
  done

  die "ERROR: Unable to locate kernel config for ${LINUX} - looking for ${config_name}"
}

kernel_initramfs_confs() {
  local config_name cfg confs

  config_name="initramfs.${TARGET_KERNEL_PATCH_ARCH:-${TARGET_ARCH}}.conf"
  confs="$(get_pkg_directory initramfs)/config/initramfs.conf"

  for cfg in ${PROJECT_DIR}/${PROJECT}/packages/initramfs/config/${config_name} \
             ${PROJECT_DIR}/${PROJECT}/devices/${DEVICE}/packages/initramfs/config/${config_name} \
             ; do
    [[ ${cfg} =~ /devices//packages/ ]] && continue
    [ -f "${cfg}" ] && confs+=" ${cfg}"
  done

  echo "$confs"
}


kernel_make() {
  (
    setup_pkg_config_host

    LDFLAGS="" make CROSS_COMPILE=${TARGET_KERNEL_PREFIX} \
      ARCH="${TARGET_KERNEL_ARCH}" \
      HOSTCC="${TOOLCHAIN}/bin/host-gcc" \
      HOSTCXX="${TOOLCHAIN}/bin/host-g++" \
      HOSTCFLAGS="${HOST_CFLAGS}" \
      HOSTLDFLAGS="${HOST_LDFLAGS}" \
      HOSTCXXFLAGS="${HOST_CXXFLAGS}" \
      DEPMOD="${TOOLCHAIN}/bin/depmod" \
      "$@"
  )
}

# get kernel module dir
get_module_dir() {
  if [ -n "${_CACHED_KERNEL_MODULE_DIR}" ]; then
    echo "${_CACHED_KERNEL_MODULE_DIR}"
  else
    basename $(ls -d $(get_build_dir linux)/.install_pkg/usr/lib/kernel-overlays/base/lib/modules/*)
  fi
}

# get base path to kernel modules and firmware
get_kernel_overlay_dir() {
  echo "usr/lib/kernel-overlays/${1:-base}"
}

# get full path to kernel module dir
# optional parameter specifies overlay level (default is base)
get_full_module_dir() {
  echo "$(get_kernel_overlay_dir $1)/lib/modules/$(get_module_dir)"
}

# get full path to firmware dir
# optional parameter specifies overlay level (default is base)
get_full_firmware_dir() {
  echo "$(get_kernel_overlay_dir $1)/lib/firmware"
}

fix_module_depends() {
  # modify .modinfo section in kernel module to depends on other required modules
  local MODULE="$1"
  local DEPENDS="$2"
  local OLD_DEPENDS=""
  cp ${MODULE} ${MODULE}_orig
  ${OBJDUMP} -s -j .modinfo ${MODULE}_orig | awk 'BEGIN{v=0;} /Contents/ {v=1; next;} {if (v==1) print $0;}' >new.modinfo1
  cat new.modinfo1 | cut -c7-41 | awk '{printf($0);}' | sed 's/ //g;s/../\\\x&/g;' >new.modinfo2
  /bin/echo -ne `cat new.modinfo2` | tr '\000' '\n' >new.modinfo3
  cat new.modinfo3 | awk '/^depends=/ {next;} {print $0;}' | tr '\n' '\000' >new.modinfo
  OLD_DEPENDS=$(awk '{FS="="} /depends=/ {print $2}' new.modinfo3)
  [ -n "${OLD_DEPENDS}" ] && DEPENDS="${OLD_DEPENDS},${DEPENDS}"
  /bin/echo -ne "depends=${DEPENDS}\0" >>new.modinfo
  $OBJCOPY --remove-section=.modinfo --add-section=.modinfo=new.modinfo --set-section-flags .modinfo=contents,alloc,load,readonly,data ${MODULE}_orig ${MODULE}
  rm new.modinfo*
}


### ADDON HELPERS ###
install_binary_addon() {
  local addon_id="$1" addon_so

  mkdir -p ${ADDON_BUILD}/${addon_id}/
  cp -R ${PKG_BUILD}/.install_pkg/usr/share/${MEDIACENTER}/addons/${addon_id}/* ${ADDON_BUILD}/${addon_id}/

  addon_so=$(xmlstarlet sel -t -v "/addon/extension/@library_linux" ${ADDON_BUILD}/${addon_id}/addon.xml || :)
  if [ -n "$addon_so" ]; then
    cp -L ${PKG_BUILD}/.install_pkg/usr/lib/${MEDIACENTER}/addons/${addon_id}/$addon_so ${ADDON_BUILD}/${addon_id}/
    chmod +x ${ADDON_BUILD}/${addon_id}/$addon_so
  fi

  if [ -d ${PKG_BUILD}/.install_pkg/usr/lib/kernel-overlays/${addon_id} ] ; then
    mkdir -p ${ADDON_BUILD}/${addon_id}/kernel-overlay
    cp -PR ${PKG_BUILD}/.install_pkg/usr/lib/kernel-overlays/${addon_id}/* ${ADDON_BUILD}/${addon_id}/kernel-overlay
  fi
}

install_addon_source() {
  if [ -d ${PKG_DIR}/source ]; then
    cp -R ${PKG_DIR}/source/* "$1"
  fi
}

install_addon_images() {
  local dest_dir="$1"

  if [ -f "${PKG_DIR}/icon/icon.png" ]; then
    mkdir -p "${dest_dir}/resources"
    cp "${PKG_DIR}/icon/icon.png" "${dest_dir}/resources"
  fi

  if [ -f "${DISTRO_DIR}/${DISTRO}/addons/fanart.png" ]; then
    mkdir -p "${dest_dir}/resources"
    cp "${DISTRO_DIR}/${DISTRO}/addons/fanart.png" "${dest_dir}/resources"
  fi
}

create_addon_xml() {
  local addon_xml addon_version addon_name provider_name requires requires_addonname requires_addonversion screenshots
  local tmp_changelog

  addon_xml="$1/addon.xml"

  IFS=" "
for i in $PKG_ADDON_REQUIRES; do
  requires_addonname=`echo $i | cut -f1 -d ":"`
  requires_addonversion=`echo $i | cut -f2 -d ":"`
  requires="${requires}\n    <import addon=\"${requires}_addonname\" version=\"${requires}_addonversion\" />"
done
  unset IFS

  if [ ! -f "${addon_xml}" ] ; then
    cp ${ROOT}/config/addon/${PKG_ADDON_TYPE}.xml "${addon_xml}"
    addon_version=${PKG_ADDON_VERSION:-${ADDON_VERSION}.${PKG_REV}}
  else
    if  ! command -v xmlstarlet >/dev/null ; then
      die "*** ERROR: $ADDON has addon.xml shipped, you need 'xmlstarlet' ***" "255"
    fi
    addon_version="${PKG_ADDON_VERSION:-$(xmlstarlet sel -t -v "/addon/@version" "${addon_xml}").$PKG_REV}"
    xmlstarlet ed --inplace -u "/addon[@version]/@version" -v "$addon_version" "${addon_xml}"
  fi

  if [ -f ${PKG_DIR}/changelog.txt ]; then
    tmp_changelog="$(mktemp)"
    cat ${PKG_DIR}/changelog.txt | xmlstarlet esc >"${tmp_changelog}"
    sed -e "/@PKG_ADDON_NEWS@/ \
         {
           r ${tmp_changelog}
           d
         }" -i "${addon_xml}"
    rm -f "${tmp_changelog}"
  else
    sed -e "s|@PKG_ADDON_NEWS@||g" -i "${addon_xml}"
  fi

  provider_name=${PKG_MAINTAINER:-"Team CoreELEC"}
  addon_name=${PKG_ADDON_NAME:-"${PKG_NAME}"}

  for f in ${PKG_DIR}/source/resources/screenshot-*.{jpg,png}; do
    if [ -f "$f" ]; then
      screenshots+="<screenshot>resources/$(basename $f)</screenshot>\n"
    fi
  done

  sed -e "s|@PKG_ADDON_ID@|${PKG_ADDON_ID}|g" \
      -e "s|@ADDON_NAME@|${addon_name}|g" \
      -e "s|@ADDON_VERSION@|$addon_version|g" \
      -e "s|@REQUIRES@|${requires}|g" \
      -e "s|@PKG_SHORTDESC@|${PKG_SHORTDESC}|g" \
      -e "s|@OS_VERSION@|${OS_VERSION}|g" \
      -e "s|@PKG_LONGDESC@|${PKG_LONGDESC}|g" \
      -e "s|@PKG_DISCLAIMER@|$PKG_DISCLAIMER|g" \
      -e "s|@PROVIDER_NAME@|${provider_name}|g" \
      -e "s|@PKG_ADDON_PROVIDES@|${PKG_ADDON_PROVIDES}|g" \
      -e "s|@PKG_ADDON_SCREENSHOT@|${screenshots}|g" \
      -e "s|@PKG_ADDON_BROKEN@|${PKG_ADDON_BROKEN}|g" \
      -i "${addon_xml}"
}

install_addon_files() {
  mkdir -p "$1"

  install_addon_source "$1"
  install_addon_images "$1"
  create_addon_xml "$1"
}

install_driver_addon_files() {
  if [ "$#" -eq 0 ] ; then
    die "$(print_color CLR_ERROR "no module search path defined")"
  fi

  PKG_MODULE_DIR="${INSTALL}/$(get_full_module_dir ${PKG_ADDON_ID})/updates/${PKG_ADDON_ID}"
  PKG_ADDON_DIR="${INSTALL}/usr/share/${MEDIACENTER}/addons/${PKG_ADDON_ID}"

  mkdir -p $PKG_MODULE_DIR
  find $@ -name \*.ko -exec cp {} $PKG_MODULE_DIR \;

  find $PKG_MODULE_DIR -name \*.ko -exec ${TARGET_KERNEL_PREFIX}strip --strip-debug {} \;

  mkdir -p $PKG_ADDON_DIR
  cp ${PKG_DIR}/changelog.txt $PKG_ADDON_DIR
  install_addon_files "$PKG_ADDON_DIR"
}


### TARGET CONFIGURATION HELPERS ###
add_user() {
  # Usage: add_user "username" "password" "userid" "groupid" "description" "home" "shell"
  mkdir -p ${INSTALL}/etc
  touch ${INSTALL}/etc/passwd
  if ! grep -q "^$1:" ${INSTALL}/etc/passwd; then
    echo "$1:x:$3:$4:$5:$6:$7" >> ${INSTALL}/etc/passwd
  fi

  mkdir -p ${INSTALL}/usr/cache
  touch ${INSTALL}/usr/cache/shadow
  ln -sf /storage/.cache/shadow ${INSTALL}/etc/shadow 2>/dev/null || true

  PASSWORD="$2"
  if [ "$PASSWORD" = "x" ]; then
    PASSWORD="*"
  fi
  if ! grep -q "^$1:" ${INSTALL}/usr/cache/shadow; then
    echo "$1:$PASSWORD:::::::" >> ${INSTALL}/usr/cache/shadow
  fi
}

add_group() {
  # Usage: add_group "groupname" "groupid" ("members")
  mkdir -p ${INSTALL}/etc
  touch ${INSTALL}/etc/group
  if [ -z "`grep "$1:" ${INSTALL}/etc/group`" ]; then
    echo "$1:x:$2:$3" >> ${INSTALL}/etc/group
  fi
}

# Usage: enable_service <unit> [target]
enable_service() {
  local unit="$1"
  local unit_dir="/usr/lib/systemd/system"
  local target="$2"
  local target_dir=${INSTALL}

  [ -f "$target_dir/$unit_dir/$unit" ] || die
  if [ -z "$target" ] ; then
    for target in `grep '^WantedBy' $target_dir/$unit_dir/$unit | cut -f2 -d=` ; do
      if [ -n "$target" ]; then
        mkdir -p ${target_dir}/$unit_dir/${target}.wants
        ln -sf ../${unit} ${target_dir}/$unit_dir/${target}.wants/
      fi
    done
  fi
  for target in `grep '^Alias' $target_dir/$unit_dir/$unit | cut -f2 -d=` ; do
    if [ -n "$target" ]; then
      ln -sf ${unit} ${target_dir}/$unit_dir/${target}
    fi
  done
}


### MULTI-THREADED FUNCTION HELPERS ###
# Test MTWITHLOCKS so that these functions are a no-op during non-multithreaded builds.

# Prevent concurrent modifications to a package (unpack) or
# package:target (install/build).
#
# If a package is already locked and the owner is ourselves
# then assume we already have the required lock.
pkg_lock() {
  [ "${MTWITHLOCKS}" != "yes" ] && return 0

  local pkg="$1" task="$2" parent_pkg="$3"
  local this_job="${MTJOBID}"
  local lock_job lock_seq lock_task lock_pkg locked=no idwidth
  local fail_seq

  exec 98>"${THREAD_CONTROL}/locks/${pkg}.${task}"
  while [ : ]; do
    read -r lock_job lock_seq lock_task lock_pkg <<<$(cat "${THREAD_CONTROL}/locks/${pkg}.${task}.owner" 2>/dev/null)
    [ -n "${lock_job}" ] && break
    flock --wait 1 --exclusive 98 && locked=yes && break
  done

  if [ "${locked}" = "no" -a "${lock_job}/${lock_seq}" != "${this_job}/${PARALLEL_SEQ}" ]; then
    [ "${THREADCOUNT}" = "0" ] && idwidth=${#MTMAXJOBS} || idwidth=2
    pkg_lock_status "STALLED" "${parent_pkg}" "${task}" "$(printf "waiting on [%0*d] %s %s" ${idwidth} ${lock_job} "${lock_task}" "${lock_pkg}")"
    flock --exclusive 98
  fi

  # As we now have the lock, if .failed still exists then a previous process must have failed
  if [ -f "${THREAD_CONTROL}/locks/${pkg}.${task}.failed" ]; then
    fail_seq="$(< "${THREAD_CONTROL}/locks/${pkg}.${task}.failed")"
    print_color CLR_ERROR "FAILURE: ${pkg}.${task}.failed exists, a previous dependency process has failed (seq: ${fail_seq})\n"
    return 1
  fi

  pkg_lock_status "LOCKED" "${pkg}" "${task}"
}

# Log additional information for a locked package.
pkg_lock_status() {
  [ "${MTWITHLOCKS}" != "yes" ] && return 0

  local status="$1" pkg="$2" task="$3" msg="$4"
  local this_job="${MTJOBID}" line idwidth

  [ "${THREADCOUNT}" = "0" ] && idwidth=${#MTMAXJOBS} || idwidth=2

  (
    flock --exclusive 94

    printf -v line "%s: <%06d> [%0*d/%0*d] %-7s %-7s %-35s" \
      "$(date +%Y-%m-%d\ %H:%M:%S.%N)" $$ ${idwidth} ${this_job} ${#MTMAXJOBS} ${PARALLEL_SEQ:-0} "${status}" "${task}" "${pkg}"
    [ -n "${msg}" ] && line+=" (${msg})"

    echo "${line}" >>"${THREAD_CONTROL}/history"

    if [ "${DASHBOARD}" != "no" ]; then
      update_dashboard "${status}" "${pkg}" "${task}" "${msg}"
    fi
  ) 94>"${THREAD_CONTROL}/locks/.history"

  if [ "${status}" = "LOCKED" ]; then
    echo "${PARALLEL_SEQ}" > "${THREAD_CONTROL}/locks/${pkg}.${task}.failed"
    echo "${this_job} ${PARALLEL_SEQ} ${task} ${pkg}" >"${THREAD_CONTROL}/locks/${pkg}.${task}.owner"
  elif [ "${status}" = "UNLOCK" ]; then
    rm -f "${THREAD_CONTROL}/locks/${pkg}.${task}.owner" || : #
    rm -f "${THREAD_CONTROL}/locks/${pkg}.${task}.failed" || : #
  fi

  return 0
}

update_dashboard() {
  [ "${MTWITHLOCKS}" != "yes" ] && return 0

  local status="$1" pkg="$2" task="$3" msg="$4"
  local line sedline preamble num elapsed projdevarch
  local boldred boldgreen boldyellow endcolor idwidth

  sedline=$((MTJOBID + 2))

  [ "${THREADCOUNT}" = "0" ] && idwidth=${#MTMAXJOBS} || idwidth=2

  num=$(< "${THREAD_CONTROL}/status.max")
  if [ ${num} -lt ${sedline} ]; then
    echo ${sedline} >"${THREAD_CONTROL}/status.max"
    for i in $(seq $((num + 1)) ${sedline}); do echo "" >>"${THREAD_CONTROL}/status"; done
  fi

  num=$(< "${THREAD_CONTROL}/progress.prev")
  projdevarch="${PROJECT}/"
  [ -n "${DEVICE}" ] && projdevarch+="${DEVICE}/"
  projdevarch+="${TARGET_ARCH}"
  [ -n "${BUILD_SUFFIX}" ] && projdevarch+=", ${BUILD_SUFFIX}"
  TZ=UTC0 printf -v elapsed "%(%H:%M:%S)T" $(($(date +%s) - MTBUILDSTART))
  printf -v preamble "%s Dashboard (%s) - %d of %d jobs completed, %s elapsed" "${DISTRONAME}" "${projdevarch}" $((num + 1)) ${MTMAXJOBS} "${elapsed}"
  printf -v preamble "%b%-105s %s" "\e[2J\e[0;0H" "${preamble//\//\\/}" "$(date "+%Y-%m-%d %H:%M:%S")"

  if [ "${DISABLE_COLORS}" != "yes" ]; then
    boldred="\e[1;31m"
    boldgreen="\e[1;32m"
    boldyellow="\e[1;33m"
    white="\e[0;37m"
    endcolor="\e[0m"

    case "${status}" in
      IDLE)    color="${white}";;
      STALLED) color="${boldyellow}";;
      MUTEX/W) color="${boldyellow}";;
      FAILED ) color="${boldred}";;
      *)       color="${boldgreen}";;
    esac
  fi

  printf -v line "[%0*d\/%0*d] %b%-7s%b %-7s %-35s" ${idwidth} ${MTJOBID} ${#MTMAXJOBS} ${PARALLEL_SEQ:-0} "${color}" "${status//\//\\/}" "${endcolor}" "${task}" "${pkg}"
  [ -n "${msg}" ] && line+=" ${msg//\//\\/}"

  sed -e "1s/.*/${preamble}/;${sedline}s/.*/${line}/" -i "${THREAD_CONTROL}/status"
}

# Thread concurrency helpers to avoid concurrency issues with some code,
# eg. when Python installs directly into ${TOOLCHAIN}.
acquire_exclusive_lock() {
  [ "${MTWITHLOCKS}" != "yes" ] && return 0

  local pkg="$1" task="$2" lockfile="${3:-global}"
  local this_job="${MTJOBID}"
  local lock_job lock_seq lock_task lock_pkg locked=no idwidth

  exec 96>"${THREAD_CONTROL}/locks/.mutex.${lockfile}"
  while [ : ]; do
    read -r lock_job lock_seq lock_task lock_pkg <<<$(cat "${THREAD_CONTROL}/locks/.mutex.${lockfile}.owner" 2>/dev/null)
    [ -n "${lock_job}" ] && break
    flock --wait 1 --exclusive 96 && locked=yes && break
  done

  if [ "${locked}" = "no" -a "${lock_job}/${lock_seq}" != "${this_job}/${PARALLEL_SEQ}" ]; then
    [ "${THREADCOUNT}" = "0" ] && idwidth=${#MTMAXJOBS} || idwidth=2
    pkg_lock_status "MUTEX/W" "${pkg}" "${task}" "$(printf "mutex: %s; waiting on [%0*d] %s %s" "${lockfile}" ${idwidth} ${lock_job} "${lock_task}" "${lock_pkg}")"
    flock --exclusive 96
  fi

  pkg_lock_status "MUTEX" "${pkg}" "${task}" "mutex: ${lockfile}"

  echo "${this_job} ${PARALLEL_SEQ} ${task} ${pkg}" >"${THREAD_CONTROL}/locks/.mutex.${lockfile}.owner"
}

release_exclusive_lock() {
  [ "${MTWITHLOCKS}" != "yes" ] && return 0

  local pkg="$1" task="$2" lockfile="${3:-global}"

  pkg_lock_status "ACTIVE" "${pkg}" "${task}"

  rm -f "${THREAD_CONTROL}/locks/.mutex.${lockfile}.owner" || : #
  flock --unlock 96 2>/dev/null
}

# Execute single command using mutex
exec_thread_safe() {
  local result
  acquire_exclusive_lock "${PKG_NAME:exec}" "execcmd"
  $@
  result=$?
  release_exclusive_lock "${PKG_NAME:exec}" "execcmd"
  return ${result}
}

### Generate System Documentation

clean_doc_cache() {
  DOCTMP="${ROOT}/.doc_cache/${DEVICE}"
  if [ -d "${DOCTMP}" ]
  then
    rm -rf "${DOCTMP}"
  fi
}

start_system_doc() {
  if [ -z "${SYSDOC}" ]
  then
    echo "Unable to generate documentation, define SYSDOC in options."
    exit 1
  fi
  if [ ! -d "${SYSDOCROOT}" ]
  then
    mkdir ${SYSDOCROOT}
  fi
  if [ -e "${SYSDOC}.md" ]
  then
    rm -f ${SYSDOC}.md
  fi
  if [ -e "${ROOT}/templates/HEADER.md" ]
  then
    cat ${ROOT}/templates/HEADER.md >${SYSDOC}.md
  fi
  DOCTEMPLATE="$(basename ${SYSDOC})"
  if [ -e "${ROOT}/templates/${DOCTEMPLATE}.md" ]
  then
    cat ${ROOT}/templates/${DOCTEMPLATE}.md >>${SYSDOC}.md
  fi
  cat <<EOF >>${SYSDOC}.md
|Manufacturer|System|Release Date|Games Path|Supported Extensions|Emulator / Core|
|----|----|----|----|----|----|
EOF
}

add_system_doc() {
  echo -n "|${SYSTEM_MANUFACTURER}|${SYSTEM_FULLNAME} (${SYSTEM_NAME})|${SYSTEM_RELEASE}|\`$(basename ${SYSTEM_PATH})\`|${SYSTEM_EXTENSION}|" >>${DOCTMP}/${1}:system.tmp
}

add_emu_doc() {
  if [ ! -d "${DOCTMP}" ]
  then
    mkdir -p "${DOCTMP}"
  fi
  if [ "${4}" = "true" ]
  then
    DEFAULT=" (default)"
  else
    unset DEFAULT
  fi
  echo -n "**${2}:** ${3}${DEFAULT}<br>" >>${DOCTMP}/${1}:emulators.tmp
}

mk_system_doc() {
  for system in $(ls ${DOCTMP}/ | awk 'BEGIN {FS=":"} {print $1}' | sort | uniq)
  do
    cat ${DOCTMP}/${system}:system.tmp >>${SYSDOC}.tmp
    if [ -e "${DOCTMP}/${system}:emulators.tmp" ]
    then
      cat ${DOCTMP}/${system}:emulators.tmp >>${SYSDOC}.tmp
    fi
    echo "|" >>${SYSDOC}.tmp
  done
  cat ${SYSDOC}.tmp | sort -f >>${SYSDOC}.md
  rm -f ${SYSDOC}.tmp
}

### Generate ES Systems

clean_es_cache() {
  ESTMP="${ROOT}/.es_cache/${DEVICE}"
  if [ -d "${ESTMP}" ]
  then
    rm -rf "${ESTMP}"
  fi
}

add_emu_core() {
  if [ ! -d "${ESTMP}" ]
  then
    mkdir -p "${ESTMP}"
  fi

  # Schema: emulator|core|true/false
  echo "${2}|${3}|${4}" >>${ESTMP}/${1}-emulators.tmp
  add_emu_doc $*
}

mk_es_systems() {

  cat <<EOF >${ESTMP}/.es_systems.cfg
<?xml version="1.0" encoding="UTF-8"?>
<systemList>
EOF
  rm -f ${ESTMP}/*-emulators.tmp
  for essystem in $(ls ${ESTMP}/*.tmp | sort)
  do
    cat ${essystem} >>${ESTMP}/.es_systems.cfg
  done
  cat <<EOF >>${ESTMP}/.es_systems.cfg
</systemList>
EOF
xmlstarlet fo -t ${ESTMP}/.es_systems.cfg >${ESTMP}/es_systems.cfg 2>/dev/null

} 

add_system_dir() {
  if [ ! -d "${ESTMP}" ]
  then
    mkdir -p "${ESTMP}"
  fi
  cat <<EOF >>${ESTMP}/system-dirs.conf
d	${1}			0777 root root - -
EOF
}

add_es_system() {
  if [ -e "${ROOT}/config/emulators/${1}.conf" ]
  then
    . ${ROOT}/config/emulators/${1}.conf
  fi

  if [ ! -d "${ESTMP}" ]
  then
    mkdir -p "${ESTMP}"
  fi

  if [ ! -e "${ESTMP}/${SYSTEM_NAME}.tmp" ]
  then
    cat <<EOF >${ESTMP}/${SYSTEM_NAME}.tmp
<system>
	<name>${SYSTEM_NAME}</name>
	<fullname>${SYSTEM_FULLNAME}</fullname>
	<manufacturer>${SYSTEM_MANUFACTURER}</manufacturer>
	<release>${SYSTEM_RELEASE}</release>
	<hardware>${SYSTEM_HARDWARE}</hardware>
	<path>${SYSTEM_PATH}</path>
	<extension>${SYSTEM_EXTENSION}</extension>
	<command>${SYSTEM_COMMAND}</command>
	<platform>${SYSTEM_PLATFORM}</platform>
	<theme>${SYSTEM_THEME}</theme>
</system>
EOF
  fi

  add_system_dir "${SYSTEM_PATH}"

  if [ -e "${ESTMP}/${SYSTEM_NAME}-emulators.tmp" ]
  then
    while read -r line
    do
      SYSTEM_EMULATOR=$(echo ${line} | awk 'BEGIN {FS="|"} {print $1}')
      SYSTEM_CORE=$(echo ${line} | awk 'BEGIN {FS="|"} {print $2}')
      SYSTEM_DEFAULT=$(echo ${line} | awk 'BEGIN {FS="|"} {print $3}')

      ### Check to see if we've already added an emulator key.
      EMTEST=$(xmlstarlet sel -t -c "//system/emulators" ${ESTMP}/${SYSTEM_NAME}.tmp 2>/dev/null ||:)
      if [ -z "${EMTEST}" ]
      then
        ### Add the emulator element
        xmlstarlet ed --omit-decl --inplace \
          -s "//system" -t elem -n "emulators" -v "" \
          ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null
      fi

      ### Check to see if we've already added an emulator key.
      EETEST=$(xmlstarlet sel -t -c "//system/emulators/emulator[@name=\"${SYSTEM_EMULATOR}\"]" ${ESTMP}/${SYSTEM_NAME}.tmp 2>/dev/null ||:)
      if [ -z "${EETEST}" ]
      then
        ### Add the emulator element
        xmlstarlet ed --omit-decl --inplace \
          -s "//system/emulators" -t elem -n "emulator" -v "" \
          ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null
      fi

      ### Add an attribute defining the emulator's name.
      xmlstarlet ed --omit-decl --inplace \
          -s "//system/emulators/emulator[not(@name)]" -t attr -n "name" -v "${SYSTEM_EMULATOR}" \
          ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null

      ### Check to see if we've already added a core element.
      COTEST=$(xmlstarlet sel -t -c "//system/emulators/emulator[@name=\"${SYSTEM_EMULATOR}\"]/cores/core" ${ESTMP}/${SYSTEM_NAME}.tmp 2>/dev/null ||:)
      if [ -z "${COTEST}" ]
      then
        xmlstarlet ed --omit-decl --inplace \
            -s "//system/emulators/emulator[@name=\"${SYSTEM_EMULATOR}\"]" -t elem -n "cores" -v "" \
            ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null
      fi

      ### Add each core.
      xmlstarlet ed --omit-decl --inplace \
          -s "//system/emulators/emulator[@name=\"${SYSTEM_EMULATOR}\"]/cores" -t elem -n "core" -v "${SYSTEM_CORE}" \
          ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null

      if [ "${SYSTEM_DEFAULT}" = "true" ]
      then
        ### Add an attribute defining the default core
        xmlstarlet ed --omit-decl --inplace \
            -i "//system/emulators/emulator[@name=\"${SYSTEM_EMULATOR}\"]/cores/core" -t attr -n "default" -v "true" \
            ${ESTMP}/${SYSTEM_NAME}.tmp 2>&1 >/dev/null
      fi
    done <${ESTMP}/${SYSTEM_NAME}-emulators.tmp
  fi
  add_system_doc ${SYSTEM_NAME}
}

# Use distribution functions if any
if [ -f "distributions/${DISTRO}/config/functions" ]; then
  . distributions/${DISTRO}/config/functions
fi