eclass/lua-utils.eclass - third_party/overlays/portage-stable - Git at Google

 # Copyright 1999-2021 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2

 # @ECLASS: lua-utils.eclass
 # @MAINTAINER:
 # William Hubbs <williamh@gentoo.org>
 # Marek Szuba <marecki@gentoo.org>
 # @AUTHOR:
 # Marek Szuba <marecki@gentoo.org>
 # Based on python-utils-r1.eclass by Michał Górny <mgorny@gentoo.org> et al.
 # @SUPPORTED_EAPIS: 7 8
 # @BLURB: Utility functions for packages with Lua parts
 # @DESCRIPTION:
 # A utility eclass providing functions to query Lua implementations,
 # install Lua modules and scripts.
 #
 # This eclass neither sets any metadata variables nor exports any phase
 # functions. It can be inherited safely.

 case ${EAPI} in
 	7|8)
 		;;
 	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
 esac

 if [[ ! ${_LUA_UTILS_R0} ]]; then

 inherit toolchain-funcs

 # @ECLASS-VARIABLE: _LUA_ALL_IMPLS
 # @INTERNAL
 # @DESCRIPTION:
 # All supported Lua implementations, most preferred last
 _LUA_ALL_IMPLS=(
 	luajit
 	lua5-1
 	lua5-3
 	lua5-4
 )
 readonly _LUA_ALL_IMPLS

 # @ECLASS-VARIABLE: _LUA_HISTORICAL_IMPLS
 # @INTERNAL
 # @DESCRIPTION:
 # All historical Lua implementations that are no longer supported.
 _LUA_HISTORICAL_IMPLS=(
 	lua5-2
 )
 readonly _LUA_HISTORICAL_IMPLS

 # @FUNCTION: _lua_set_impls
 # @INTERNAL
 # @DESCRIPTION:
 # Check LUA_COMPAT for well-formedness and validity, then set
 # two global variables:
 #
 # - _LUA_SUPPORTED_IMPLS containing valid implementations supported
 #   by the ebuild (LUA_COMPAT minus dead implementations),
 #
 # - and _LUA_UNSUPPORTED_IMPLS containing valid implementations that
 #   are not supported by the ebuild.
 #
 # Implementations in both variables are ordered using the pre-defined
 # eclass implementation ordering.
 #
 # This function must only be called once.
 _lua_set_impls() {
 	local i

 	if ! declare -p LUA_COMPAT &>/dev/null; then
 		die 'LUA_COMPAT not declared.'
 	fi
 	if [[ $(declare -p LUA_COMPAT) != "declare -a"* ]]; then
 		die 'LUA_COMPAT must be an array.'
 	fi

 	local supp=() unsupp=()

 	for i in "${_LUA_ALL_IMPLS[@]}"; do
 		if has "${i}" "${LUA_COMPAT[@]}"; then
 			supp+=( "${i}" )
 		else
 			unsupp+=( "${i}" )
 		fi
 	done

 	if [[ ! ${supp[@]} ]]; then
 		die "No supported implementation in LUA_COMPAT."
 	fi

 	if [[ ${_LUA_SUPPORTED_IMPLS[@]} ]]; then
 		# set once already, verify integrity
 		if [[ ${_LUA_SUPPORTED_IMPLS[@]} != ${supp[@]} ]]; then
 			eerror "Supported impls (LUA_COMPAT) changed between inherits!"
 			eerror "Before: ${_LUA_SUPPORTED_IMPLS[*]}"
 			eerror "Now   : ${supp[*]}"
 			die "_LUA_SUPPORTED_IMPLS integrity check failed"
 		fi
 		if [[ ${_LUA_UNSUPPORTED_IMPLS[@]} != ${unsupp[@]} ]]; then
 			eerror "Unsupported impls changed between inherits!"
 			eerror "Before: ${_LUA_UNSUPPORTED_IMPLS[*]}"
 			eerror "Now   : ${unsupp[*]}"
 			die "_LUA_UNSUPPORTED_IMPLS integrity check failed"
 		fi
 	else
 		_LUA_SUPPORTED_IMPLS=( "${supp[@]}" )
 		_LUA_UNSUPPORTED_IMPLS=( "${unsupp[@]}" )
 		readonly _LUA_SUPPORTED_IMPLS _LUA_UNSUPPORTED_IMPLS
 	fi
 }

 # @FUNCTION: _lua_wrapper_setup
 # @USAGE: [<path> [<impl>]]
 # @INTERNAL
 # @DESCRIPTION:
 # Create proper Lua executables and pkg-config wrappers
 # (if available) in the directory named by <path>. Set up PATH
 # and PKG_CONFIG_PATH appropriately. <path> defaults to ${T}/${ELUA}.
 #
 # The wrappers will be created for implementation named by <impl>,
 # or for one named by ${ELUA} if no <impl> passed.
 #
 # If the named directory contains a lua symlink already, it will
 # be assumed to contain proper wrappers already and only environment
 # setup will be done. If wrapper update is requested, the directory
 # shall be removed first.
 _lua_wrapper_setup() {
 	debug-print-function ${FUNCNAME} "${@}"

 	local workdir=${1:-${T}/${ELUA}}
 	local impl=${2:-${ELUA}}

 	[[ ${workdir} ]] || die "${FUNCNAME}: no workdir specified."
 	[[ ${impl} ]] || die "${FUNCNAME}: no impl nor ELUA specified."

 	if [[ ! -x ${workdir}/bin/lua ]]; then
 		mkdir -p "${workdir}"/{bin,pkgconfig} || die

 		# Clean up, in case we were supposed to do a cheap update
 		rm -f "${workdir}"/bin/lua{,c} || die
 		rm -f "${workdir}"/pkgconfig/lua.pc || die

 		local ELUA LUA
 		_lua_export "${impl}" ELUA LUA

 		# Lua interpreter
 		ln -s "${EPREFIX}"/usr/bin/${ELUA} "${workdir}"/bin/lua || die

 		# Lua compiler, or a stub for it in case of luajit
 		if [[ ${ELUA} == luajit ]]; then
 			# Just in case
 			ln -s "${EPREFIX}"/bin/true "${workdir}"/bin/luac || die
 		else
 			ln -s "${EPREFIX}"/usr/bin/${ELUA/a/ac} "${workdir}"/bin/luac || die
 		fi

 		# pkg-config
 		ln -s "${EPREFIX}"/usr/$(get_libdir)/pkgconfig/${ELUA}.pc \
 			"${workdir}"/pkgconfig/lua.pc || die
 	fi

 	# Now, set the environment.
 	# But note that ${workdir} may be shared with something else,
 	# and thus already on top of PATH.
 	if [[ ${PATH##:*} != ${workdir}/bin ]]; then
 		PATH=${workdir}/bin${PATH:+:${PATH}}
 	fi
 	if [[ ${PKG_CONFIG_PATH##:*} != ${workdir}/pkgconfig ]]; then
 		PKG_CONFIG_PATH=${workdir}/pkgconfig${PKG_CONFIG_PATH:+:${PKG_CONFIG_PATH}}
 	fi
 	export PATH PKG_CONFIG_PATH
 }

 # @ECLASS-VARIABLE: ELUA
 # @DEFAULT_UNSET
 # @DESCRIPTION:
 # The executable name of the current Lua interpreter. This variable is set
 # automatically in functions called by lua_foreach_impl().
 #
 # Example value:
 # @CODE
 # lua5.1
 # @CODE

 # @ECLASS-VARIABLE: LUA
 # @DEFAULT_UNSET
 # @DESCRIPTION:
 # The absolute path to the current Lua interpreter. This variable is set
 # automatically in functions called by lua_foreach_impl().
 #
 # Example value:
 # @CODE
 # /usr/bin/lua5.1
 # @CODE

 # @FUNCTION: _lua_get_library_file
 # @USAGE: <impl>
 # @INTERNAL
 # @DESCRIPTION:
 # Get the core part (i.e. without the extension) of the library name,
 # with path, of the given Lua implementation.
 # Used internally by _lua_export().
 _lua_get_library_file() {
 	local impl="${1}"
 	local libdir libname

 	case ${impl} in
 		luajit)
 			libname=lib$($(tc-getPKG_CONFIG) --variable libname ${impl}) || die
 			;;
 		lua*)
 			libname=lib${impl}
 			;;
 		*)
 			die "Invalid implementation: ${impl}"
 			;;
 	esac

 	libdir=$($(tc-getPKG_CONFIG) --variable libdir ${impl}) || die
 	libdir="${libdir#${ESYSROOT#${SYSROOT}}}"

 	debug-print "${FUNCNAME}: libdir = ${libdir}, libname = ${libname}"
 	echo "${libdir}/${libname}"
 }

 # @FUNCTION: _lua_export
 # @USAGE: [<impl>] <variables>...
 # @INTERNAL
 # @DESCRIPTION:
 # Set and export the Lua implementation-relevant variables passed
 # as parameters.
 #
 # The optional first parameter may specify the requested Lua
 # implementation (either as LUA_TARGETS value, e.g. lua5-4,
 # or an ELUA one, e.g. lua5.4). If no implementation passed,
 # the current one will be obtained from ${ELUA}.
 _lua_export() {
 	debug-print-function ${FUNCNAME} "${@}"

 	local impl var

 	case "${1}" in
 		luajit)
 			impl=${1}
 			shift
 			;;
 		lua*)
 			impl=${1/-/.}
 			shift
 			;;
 		*)
 			impl=${ELUA}
 			if [[ -z ${impl} ]]; then
 				die "_lua_export called without a Lua implementation and ELUA is unset"
 			fi
 			;;
 	esac
 	debug-print "${FUNCNAME}: implementation: ${impl}"

 	for var; do
 		case "${var}" in
 			ELUA)
 				export ELUA=${impl}
 				debug-print "${FUNCNAME}: ELUA = ${ELUA}"
 				;;
 			LUA)
 				export LUA="${EPREFIX}"/usr/bin/${impl}
 				debug-print "${FUNCNAME}: LUA = ${LUA}"
 				;;
 			LUA_CFLAGS)
 				local val

 				val=$($(tc-getPKG_CONFIG) --cflags ${impl}) || die

 				export LUA_CFLAGS=${val}
 				debug-print "${FUNCNAME}: LUA_CFLAGS = ${LUA_CFLAGS}"
 				;;
 			LUA_CMOD_DIR)
 				local val

 				val=$($(tc-getPKG_CONFIG) --variable INSTALL_CMOD ${impl}) || die
 				val="${val#${ESYSROOT#${SYSROOT}}}"

 				export LUA_CMOD_DIR=${val}
 				debug-print "${FUNCNAME}: LUA_CMOD_DIR = ${LUA_CMOD_DIR}"
 				;;
 			LUA_INCLUDE_DIR)
 				local val

 				val=$($(tc-getPKG_CONFIG) --variable includedir ${impl}) || die
 				val="${val#${ESYSROOT#${SYSROOT}}}"

 				export LUA_INCLUDE_DIR=${val}
 				debug-print "${FUNCNAME}: LUA_INCLUDE_DIR = ${LUA_INCLUDE_DIR}"
 				;;
 			LUA_LIBS)
 				local val

 				val=$($(tc-getPKG_CONFIG) --libs ${impl}) || die

 				export LUA_LIBS=${val}
 				debug-print "${FUNCNAME}: LUA_LIBS = ${LUA_LIBS}"
 				;;
 			LUA_LMOD_DIR)
 				local val

 				val=$($(tc-getPKG_CONFIG) --variable INSTALL_LMOD ${impl}) || die
 				val="${val#${ESYSROOT#${SYSROOT}}}"

 				export LUA_LMOD_DIR=${val}
 				debug-print "${FUNCNAME}: LUA_LMOD_DIR = ${LUA_LMOD_DIR}"
 				;;
 			LUA_PKG_DEP)
 				local d
 				case ${impl} in
 					luajit)
 						LUA_PKG_DEP="dev-lang/luajit:="
 						;;
 					lua*)
 						LUA_PKG_DEP="dev-lang/lua:${impl#lua}"
 						;;
 					*)
 						die "Invalid implementation: ${impl}"
 						;;
 				esac

 				# use-dep
 				if [[ ${LUA_REQ_USE} ]]; then
 					LUA_PKG_DEP+=[${LUA_REQ_USE}]
 				fi

 				export LUA_PKG_DEP
 				debug-print "${FUNCNAME}: LUA_PKG_DEP = ${LUA_PKG_DEP}"
 				;;
 			LUA_SHARED_LIB)
 				local val=$(_lua_get_library_file ${impl})
 				export LUA_SHARED_LIB="${val}".so
 				debug-print "${FUNCNAME}: LUA_SHARED_LIB = ${LUA_SHARED_LIB}"
 				;;
 			LUA_VERSION)
 				local val

 				val=$($(tc-getPKG_CONFIG) --modversion ${impl}) || die

 				export LUA_VERSION=${val}
 				debug-print "${FUNCNAME}: LUA_VERSION = ${LUA_VERSION}"
 				;;
 			*)
 				die "_lua_export: unknown variable ${var}"
 				;;
 		esac
 	done
 }

 # @FUNCTION: lua_enable_tests
 # @USAGE: <test-runner> <test-directory>
 # @DESCRIPTION:
 # Set up IUSE, RESTRICT, BDEPEND and src_test() for running tests
 # with the specified test runner.  Also copies the current value
 # of RDEPEND to test?-BDEPEND.  The test-runner argument must be one of:
 #
 # - busted: dev-lua/busted
 #
 # Additionally, a second argument can be passed after <test-runner>,
 # so <test-runner> will use that directory to search for tests.
 # If not passed, a default directory of <test-runner> will be used.
 #
 # - busted: spec
 #
 # This function is meant as a helper for common use cases, and it only
 # takes care of basic setup.  You still need to list additional test
 # dependencies manually.  If you have uncommon use case, you should
 # not use it and instead enable tests manually.
 #
 # This function must be called in global scope, after RDEPEND has been
 # declared.  Take care not to overwrite the variables set by it.
 lua_enable_tests() {
 	debug-print-function ${FUNCNAME} "${@}"

 	[[ ${#} -ge 1 ]] || die "${FUNCNAME} takes at least one argument: test-runner (test-directory)"
 	local test_directory
 	local test_pkg
 	case ${1} in
 		busted)
 			test_directory="${2:-spec}"
 			test_pkg="dev-lua/busted"
 			if [[ ! ${_LUA_SINGLE_R0} ]]; then
 				eval "lua_src_test() {
 					busted --lua=\"\${ELUA}\" --output=\"plainTerminal\" \"${test_directory}\" || die \"Tests fail with \${ELUA}\"
 				}"
 				src_test() {
 					lua_foreach_impl lua_src_test
 				}
 			else
 				eval "src_test() {
 					busted --lua=\"\${ELUA}\" --output=\"plainTerminal\" \"${test_directory}\" || die \"Tests fail with \${ELUA}\"
 				}"
 			fi
 			;;
 		*)
 			die "${FUNCNAME}: unsupported argument: ${1}"
 	esac

 	local test_deps=${RDEPEND}
 	if [[ -n ${test_pkg} ]]; then
 		if [[ ! ${_LUA_SINGLE_R0} ]]; then
 			test_deps+=" ${test_pkg}[${LUA_USEDEP}]"
 		else
 			test_deps+=" $(lua_gen_cond_dep "
 				${test_pkg}[\${LUA_USEDEP}]
 			")"
 		fi
 	fi
 	if [[ -n ${test_deps} ]]; then
 		IUSE+=" test"
 		RESTRICT+=" !test? ( test )"
 		BDEPEND+=" test? ( ${test_deps} )"
 	fi

 	# we need to ensure successful return in case we're called last,
 	# otherwise Portage may wrongly assume sourcing failed
 	return 0
 }

 # @FUNCTION: lua_get_CFLAGS
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the compiler flags for building against Lua,
 # for the given implementation. If no implementation is provided,
 # ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_CFLAGS() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_CFLAGS
 	echo "${LUA_CFLAGS}"
 }

 # @FUNCTION: lua_get_cmod_dir
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the name of the directory into which compiled Lua
 # modules are installed, for the given implementation. If no implementation
 # is provided, ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_cmod_dir() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_CMOD_DIR
 	echo "${LUA_CMOD_DIR}"
 }

 # @FUNCTION: lua_get_include_dir
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the name of the directory containing header files
 # of the given Lua implementation. If no implementation is provided,
 # ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_include_dir() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_INCLUDE_DIR
 	echo "${LUA_INCLUDE_DIR}"
 }

 # @FUNCTION: lua_get_LIBS
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the compiler flags for linking against Lua,
 # for the given implementation. If no implementation is provided,
 # ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_LIBS() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_LIBS
 	echo "${LUA_LIBS}"
 }

 # @FUNCTION: lua_get_lmod_dir
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the name of the directory into which native-Lua
 # modules are installed, for the given implementation. If no implementation
 # is provided, ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_lmod_dir() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_LMOD_DIR
 	echo "${LUA_LMOD_DIR}"
 }

 # @FUNCTION: lua_get_shared_lib
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the expected name, with path, of the main shared library
 # of the given Lua implementation. If no implementation is provided,
 # ${ELUA} will be used.
 #
 # Note that it is up to the ebuild maintainer to ensure Lua actually
 # provides a shared library.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_shared_lib() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_SHARED_LIB
 	echo "${LUA_SHARED_LIB}"
 }

 # @FUNCTION: lua_get_version
 # @USAGE: [<impl>]
 # @DESCRIPTION:
 # Obtain and print the full version number of the given Lua implementation.
 # If no implementation is provided, ${ELUA} will be used.
 #
 # Please note that this function requires Lua and pkg-config installed,
 # and therefore proper build-time dependencies need be added to the ebuild.
 lua_get_version() {
 	debug-print-function ${FUNCNAME} "${@}"

 	_lua_export "${@}" LUA_VERSION
 	echo "${LUA_VERSION}"
 }

 _LUA_UTILS_R0=1
 fi
	# Copyright 1999-2021 Gentoo Authors
	# Distributed under the terms of the GNU General Public License v2

	# @ECLASS: lua-utils.eclass
	# @MAINTAINER:
	# William Hubbs <williamh@gentoo.org>
	# Marek Szuba <marecki@gentoo.org>
	# @AUTHOR:
	# Marek Szuba <marecki@gentoo.org>
	# Based on python-utils-r1.eclass by Michał Górny <mgorny@gentoo.org> et al.
	# @SUPPORTED_EAPIS: 7 8
	# @BLURB: Utility functions for packages with Lua parts
	# @DESCRIPTION:
	# A utility eclass providing functions to query Lua implementations,
	# install Lua modules and scripts.
	#
	# This eclass neither sets any metadata variables nor exports any phase
	# functions. It can be inherited safely.

	case ${EAPI} in
	7\|8)
	;;
	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
	esac

	if [[ ! ${_LUA_UTILS_R0} ]]; then

	inherit toolchain-funcs

	# @ECLASS-VARIABLE: _LUA_ALL_IMPLS
	# @INTERNAL
	# @DESCRIPTION:
	# All supported Lua implementations, most preferred last
	_LUA_ALL_IMPLS=(
	luajit
	lua5-1
	lua5-3
	lua5-4
	)
	readonly _LUA_ALL_IMPLS

	# @ECLASS-VARIABLE: _LUA_HISTORICAL_IMPLS
	# @INTERNAL
	# @DESCRIPTION:
	# All historical Lua implementations that are no longer supported.
	_LUA_HISTORICAL_IMPLS=(
	lua5-2
	)
	readonly _LUA_HISTORICAL_IMPLS

	# @FUNCTION: _lua_set_impls
	# @INTERNAL
	# @DESCRIPTION:
	# Check LUA_COMPAT for well-formedness and validity, then set
	# two global variables:
	#
	# - _LUA_SUPPORTED_IMPLS containing valid implementations supported
	# by the ebuild (LUA_COMPAT minus dead implementations),
	#
	# - and _LUA_UNSUPPORTED_IMPLS containing valid implementations that
	# are not supported by the ebuild.
	#
	# Implementations in both variables are ordered using the pre-defined
	# eclass implementation ordering.
	#
	# This function must only be called once.
	_lua_set_impls() {
	local i

	if ! declare -p LUA_COMPAT &>/dev/null; then
	die 'LUA_COMPAT not declared.'
	fi
	if [[ $(declare -p LUA_COMPAT) != "declare -a"* ]]; then
	die 'LUA_COMPAT must be an array.'
	fi

	local supp=() unsupp=()

	for i in "${_LUA_ALL_IMPLS[@]}"; do
	if has "${i}" "${LUA_COMPAT[@]}"; then
	supp+=( "${i}" )
	else
	unsupp+=( "${i}" )
	fi
	done

	if [[ ! ${supp[@]} ]]; then
	die "No supported implementation in LUA_COMPAT."
	fi

	if [[ ${_LUA_SUPPORTED_IMPLS[@]} ]]; then
	# set once already, verify integrity
	if [[ ${_LUA_SUPPORTED_IMPLS[@]} != ${supp[@]} ]]; then
	eerror "Supported impls (LUA_COMPAT) changed between inherits!"
	eerror "Before: ${_LUA_SUPPORTED_IMPLS[*]}"
	eerror "Now : ${supp[*]}"
	die "_LUA_SUPPORTED_IMPLS integrity check failed"
	fi
	if [[ ${_LUA_UNSUPPORTED_IMPLS[@]} != ${unsupp[@]} ]]; then
	eerror "Unsupported impls changed between inherits!"
	eerror "Before: ${_LUA_UNSUPPORTED_IMPLS[*]}"
	eerror "Now : ${unsupp[*]}"
	die "_LUA_UNSUPPORTED_IMPLS integrity check failed"
	fi
	else
	_LUA_SUPPORTED_IMPLS=( "${supp[@]}" )
	_LUA_UNSUPPORTED_IMPLS=( "${unsupp[@]}" )
	readonly _LUA_SUPPORTED_IMPLS _LUA_UNSUPPORTED_IMPLS
	fi
	}

	# @FUNCTION: _lua_wrapper_setup
	# @USAGE: [<path> [<impl>]]
	# @INTERNAL
	# @DESCRIPTION:
	# Create proper Lua executables and pkg-config wrappers
	# (if available) in the directory named by <path>. Set up PATH
	# and PKG_CONFIG_PATH appropriately. <path> defaults to ${T}/${ELUA}.
	#
	# The wrappers will be created for implementation named by <impl>,
	# or for one named by ${ELUA} if no <impl> passed.
	#
	# If the named directory contains a lua symlink already, it will
	# be assumed to contain proper wrappers already and only environment
	# setup will be done. If wrapper update is requested, the directory
	# shall be removed first.
	_lua_wrapper_setup() {
	debug-print-function ${FUNCNAME} "${@}"

	local workdir=${1:-${T}/${ELUA}}
	local impl=${2:-${ELUA}}

	[[ ${workdir} ]] \|\| die "${FUNCNAME}: no workdir specified."
	[[ ${impl} ]] \|\| die "${FUNCNAME}: no impl nor ELUA specified."

	if [[ ! -x ${workdir}/bin/lua ]]; then
	mkdir -p "${workdir}"/{bin,pkgconfig} \|\| die

	# Clean up, in case we were supposed to do a cheap update
	rm -f "${workdir}"/bin/lua{,c} \|\| die
	rm -f "${workdir}"/pkgconfig/lua.pc \|\| die

	local ELUA LUA
	_lua_export "${impl}" ELUA LUA

	# Lua interpreter
	ln -s "${EPREFIX}"/usr/bin/${ELUA} "${workdir}"/bin/lua \|\| die

	# Lua compiler, or a stub for it in case of luajit
	if [[ ${ELUA} == luajit ]]; then
	# Just in case
	ln -s "${EPREFIX}"/bin/true "${workdir}"/bin/luac \|\| die
	else
	ln -s "${EPREFIX}"/usr/bin/${ELUA/a/ac} "${workdir}"/bin/luac \|\| die
	fi

	# pkg-config
	ln -s "${EPREFIX}"/usr/$(get_libdir)/pkgconfig/${ELUA}.pc \
	"${workdir}"/pkgconfig/lua.pc \|\| die
	fi

	# Now, set the environment.
	# But note that ${workdir} may be shared with something else,
	# and thus already on top of PATH.
	if [[ ${PATH##:*} != ${workdir}/bin ]]; then
	PATH=${workdir}/bin${PATH:+:${PATH}}
	fi
	if [[ ${PKG_CONFIG_PATH##:*} != ${workdir}/pkgconfig ]]; then
	PKG_CONFIG_PATH=${workdir}/pkgconfig${PKG_CONFIG_PATH:+:${PKG_CONFIG_PATH}}
	fi
	export PATH PKG_CONFIG_PATH
	}

	# @ECLASS-VARIABLE: ELUA
	# @DEFAULT_UNSET
	# @DESCRIPTION:
	# The executable name of the current Lua interpreter. This variable is set
	# automatically in functions called by lua_foreach_impl().
	#
	# Example value:
	# @CODE
	# lua5.1
	# @CODE

	# @ECLASS-VARIABLE: LUA
	# @DEFAULT_UNSET
	# @DESCRIPTION:
	# The absolute path to the current Lua interpreter. This variable is set
	# automatically in functions called by lua_foreach_impl().
	#
	# Example value:
	# @CODE
	# /usr/bin/lua5.1
	# @CODE

	# @FUNCTION: _lua_get_library_file
	# @USAGE: <impl>
	# @INTERNAL
	# @DESCRIPTION:
	# Get the core part (i.e. without the extension) of the library name,
	# with path, of the given Lua implementation.
	# Used internally by _lua_export().
	_lua_get_library_file() {
	local impl="${1}"
	local libdir libname

	case ${impl} in
	luajit)
	libname=lib$($(tc-getPKG_CONFIG) --variable libname ${impl}) \|\| die
	;;
	lua*)
	libname=lib${impl}
	;;
	*)
	die "Invalid implementation: ${impl}"
	;;
	esac

	libdir=$($(tc-getPKG_CONFIG) --variable libdir ${impl}) \|\| die
	libdir="${libdir#${ESYSROOT#${SYSROOT}}}"

	debug-print "${FUNCNAME}: libdir = ${libdir}, libname = ${libname}"
	echo "${libdir}/${libname}"
	}

	# @FUNCTION: _lua_export
	# @USAGE: [<impl>] <variables>...
	# @INTERNAL
	# @DESCRIPTION:
	# Set and export the Lua implementation-relevant variables passed
	# as parameters.
	#
	# The optional first parameter may specify the requested Lua
	# implementation (either as LUA_TARGETS value, e.g. lua5-4,
	# or an ELUA one, e.g. lua5.4). If no implementation passed,
	# the current one will be obtained from ${ELUA}.
	_lua_export() {
	debug-print-function ${FUNCNAME} "${@}"

	local impl var

	case "${1}" in
	luajit)
	impl=${1}
	shift
	;;
	lua*)
	impl=${1/-/.}
	shift
	;;
	*)
	impl=${ELUA}
	if [[ -z ${impl} ]]; then
	die "_lua_export called without a Lua implementation and ELUA is unset"
	fi
	;;
	esac
	debug-print "${FUNCNAME}: implementation: ${impl}"

	for var; do
	case "${var}" in
	ELUA)
	export ELUA=${impl}
	debug-print "${FUNCNAME}: ELUA = ${ELUA}"
	;;
	LUA)
	export LUA="${EPREFIX}"/usr/bin/${impl}
	debug-print "${FUNCNAME}: LUA = ${LUA}"
	;;
	LUA_CFLAGS)
	local val

	val=$($(tc-getPKG_CONFIG) --cflags ${impl}) \|\| die

	export LUA_CFLAGS=${val}
	debug-print "${FUNCNAME}: LUA_CFLAGS = ${LUA_CFLAGS}"
	;;
	LUA_CMOD_DIR)
	local val

	val=$($(tc-getPKG_CONFIG) --variable INSTALL_CMOD ${impl}) \|\| die
	val="${val#${ESYSROOT#${SYSROOT}}}"

	export LUA_CMOD_DIR=${val}
	debug-print "${FUNCNAME}: LUA_CMOD_DIR = ${LUA_CMOD_DIR}"
	;;
	LUA_INCLUDE_DIR)
	local val

	val=$($(tc-getPKG_CONFIG) --variable includedir ${impl}) \|\| die
	val="${val#${ESYSROOT#${SYSROOT}}}"

	export LUA_INCLUDE_DIR=${val}
	debug-print "${FUNCNAME}: LUA_INCLUDE_DIR = ${LUA_INCLUDE_DIR}"
	;;
	LUA_LIBS)
	local val

	val=$($(tc-getPKG_CONFIG) --libs ${impl}) \|\| die

	export LUA_LIBS=${val}
	debug-print "${FUNCNAME}: LUA_LIBS = ${LUA_LIBS}"
	;;
	LUA_LMOD_DIR)
	local val

	val=$($(tc-getPKG_CONFIG) --variable INSTALL_LMOD ${impl}) \|\| die
	val="${val#${ESYSROOT#${SYSROOT}}}"

	export LUA_LMOD_DIR=${val}
	debug-print "${FUNCNAME}: LUA_LMOD_DIR = ${LUA_LMOD_DIR}"
	;;
	LUA_PKG_DEP)
	local d
	case ${impl} in
	luajit)
	LUA_PKG_DEP="dev-lang/luajit:="
	;;
	lua*)
	LUA_PKG_DEP="dev-lang/lua:${impl#lua}"
	;;
	*)
	die "Invalid implementation: ${impl}"
	;;
	esac

	# use-dep
	if [[ ${LUA_REQ_USE} ]]; then
	LUA_PKG_DEP+=[${LUA_REQ_USE}]
	fi

	export LUA_PKG_DEP
	debug-print "${FUNCNAME}: LUA_PKG_DEP = ${LUA_PKG_DEP}"
	;;
	LUA_SHARED_LIB)
	local val=$(_lua_get_library_file ${impl})
	export LUA_SHARED_LIB="${val}".so
	debug-print "${FUNCNAME}: LUA_SHARED_LIB = ${LUA_SHARED_LIB}"
	;;
	LUA_VERSION)
	local val

	val=$($(tc-getPKG_CONFIG) --modversion ${impl}) \|\| die

	export LUA_VERSION=${val}
	debug-print "${FUNCNAME}: LUA_VERSION = ${LUA_VERSION}"
	;;
	*)
	die "_lua_export: unknown variable ${var}"
	;;
	esac
	done
	}

	# @FUNCTION: lua_enable_tests
	# @USAGE: <test-runner> <test-directory>
	# @DESCRIPTION:
	# Set up IUSE, RESTRICT, BDEPEND and src_test() for running tests
	# with the specified test runner. Also copies the current value
	# of RDEPEND to test?-BDEPEND. The test-runner argument must be one of:
	#
	# - busted: dev-lua/busted
	#
	# Additionally, a second argument can be passed after <test-runner>,
	# so <test-runner> will use that directory to search for tests.
	# If not passed, a default directory of <test-runner> will be used.
	#
	# - busted: spec
	#
	# This function is meant as a helper for common use cases, and it only
	# takes care of basic setup. You still need to list additional test
	# dependencies manually. If you have uncommon use case, you should
	# not use it and instead enable tests manually.
	#
	# This function must be called in global scope, after RDEPEND has been
	# declared. Take care not to overwrite the variables set by it.
	lua_enable_tests() {
	debug-print-function ${FUNCNAME} "${@}"

	[[ ${#} -ge 1 ]] \|\| die "${FUNCNAME} takes at least one argument: test-runner (test-directory)"
	local test_directory
	local test_pkg
	case ${1} in
	busted)
	test_directory="${2:-spec}"
	test_pkg="dev-lua/busted"
	if [[ ! ${_LUA_SINGLE_R0} ]]; then
	eval "lua_src_test() {
	busted --lua=\"\${ELUA}\" --output=\"plainTerminal\" \"${test_directory}\" \|\| die \"Tests fail with \${ELUA}\"
	}"
	src_test() {
	lua_foreach_impl lua_src_test
	}
	else
	eval "src_test() {
	busted --lua=\"\${ELUA}\" --output=\"plainTerminal\" \"${test_directory}\" \|\| die \"Tests fail with \${ELUA}\"
	}"
	fi
	;;
	*)
	die "${FUNCNAME}: unsupported argument: ${1}"
	esac

	local test_deps=${RDEPEND}
	if [[ -n ${test_pkg} ]]; then
	if [[ ! ${_LUA_SINGLE_R0} ]]; then
	test_deps+=" ${test_pkg}[${LUA_USEDEP}]"
	else
	test_deps+=" $(lua_gen_cond_dep "
	${test_pkg}[\${LUA_USEDEP}]
	")"
	fi
	fi
	if [[ -n ${test_deps} ]]; then
	IUSE+=" test"
	RESTRICT+=" !test? ( test )"
	BDEPEND+=" test? ( ${test_deps} )"
	fi

	# we need to ensure successful return in case we're called last,
	# otherwise Portage may wrongly assume sourcing failed
	return 0
	}

	# @FUNCTION: lua_get_CFLAGS
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the compiler flags for building against Lua,
	# for the given implementation. If no implementation is provided,
	# ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_CFLAGS() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_CFLAGS
	echo "${LUA_CFLAGS}"
	}

	# @FUNCTION: lua_get_cmod_dir
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the name of the directory into which compiled Lua
	# modules are installed, for the given implementation. If no implementation
	# is provided, ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_cmod_dir() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_CMOD_DIR
	echo "${LUA_CMOD_DIR}"
	}

	# @FUNCTION: lua_get_include_dir
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the name of the directory containing header files
	# of the given Lua implementation. If no implementation is provided,
	# ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_include_dir() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_INCLUDE_DIR
	echo "${LUA_INCLUDE_DIR}"
	}

	# @FUNCTION: lua_get_LIBS
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the compiler flags for linking against Lua,
	# for the given implementation. If no implementation is provided,
	# ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_LIBS() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_LIBS
	echo "${LUA_LIBS}"
	}

	# @FUNCTION: lua_get_lmod_dir
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the name of the directory into which native-Lua
	# modules are installed, for the given implementation. If no implementation
	# is provided, ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_lmod_dir() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_LMOD_DIR
	echo "${LUA_LMOD_DIR}"
	}

	# @FUNCTION: lua_get_shared_lib
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the expected name, with path, of the main shared library
	# of the given Lua implementation. If no implementation is provided,
	# ${ELUA} will be used.
	#
	# Note that it is up to the ebuild maintainer to ensure Lua actually
	# provides a shared library.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_shared_lib() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_SHARED_LIB
	echo "${LUA_SHARED_LIB}"
	}

	# @FUNCTION: lua_get_version
	# @USAGE: [<impl>]
	# @DESCRIPTION:
	# Obtain and print the full version number of the given Lua implementation.
	# If no implementation is provided, ${ELUA} will be used.
	#
	# Please note that this function requires Lua and pkg-config installed,
	# and therefore proper build-time dependencies need be added to the ebuild.
	lua_get_version() {
	debug-print-function ${FUNCNAME} "${@}"

	_lua_export "${@}" LUA_VERSION
	echo "${LUA_VERSION}"
	}

	_LUA_UTILS_R0=1
	fi