#!/bin/bash
# Copyright 1999-2018 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

# Format of /etc/env.d/binutils/:
#  config-TARGET:	CURRENT=version for TARGET
#  TARGET-VER:		has a TARGET and VER variable

EPREFIX="@GENTOO_PORTAGE_EPREFIX@"
if [[ ${EPREFIX} == "@"GENTOO_PORTAGE_EPREFIX"@" ]] ; then
	EPREFIX=""
fi

: ${ROOT:=/}
[[ ${ROOT} != */ ]] && ROOT="${ROOT}/"
[[ ${ROOT} != /* ]] && ROOT="${PWD%/}/${ROOT}"

EROOT="${ROOT%/}${EPREFIX}/"

cd "${EPREFIX}/"

trap ":" INT QUIT TSTP

argv0=${0##*/}
FUNCTIONS_SH="${EPREFIX}/lib/gentoo/functions.sh"
source ${FUNCTIONS_SH} || {
	echo "${argv0}: Could not source ${FUNCTIONS_SH}!" 1>&2
	exit 1
}
esyslog() { :; }
die() { eerror "${argv0}: $*"; exit 1; }
umask 022

usage() {
cat << USAGE_END
Usage: ${HILITE}binutils-config${NORMAL} ${GOOD}[options]${NORMAL} ${BRACKET}[binutils profile]${NORMAL}

${HILITE}General Options:${NORMAL}
  ${GOOD}-c, --get-current-profile${NORMAL}  Print current profile
  ${GOOD}-l, --list-profiles${NORMAL}        Print a list of available profiles
  ${GOOD}-u, --uninstall${NORMAL}            Remove all signs of specified target
  ${GOOD}-d, --debug${NORMAL}                Execute with debug output

${HILITE}General Cruft:${NORMAL}
  ${GOOD}--linker${NORMAL} <linker>          Switch to specified linker (if supported)

Profile names are of the form:  ${BRACKET}<CTARGET>-<binutils version>${NORMAL}
For example:                    ${BRACKET}i686-pc-linux-gnu-2.15.92.0.2${NORMAL}

For more info, please see ${HILITE}binutils-config${NORMAL}(8).
USAGE_END

	exit ${1:-1}
}

mv_if_diff() {
	if cmp -s "$1" "$2" ; then
		rm -f "$1"
	else
		mv -f "$1" "$2"
	fi
}
atomic_ln() {
	local target=$1 linkdir=$2 linkname=$3 linktmp linkfull
	linktmp="${linkdir}/.binutils-config.tmp.${linkname}"
	linkfull="${linkdir}/${linkname}"
	if [[ -d ${linkfull} ]] ; then
		# if linking to a dir, we need a little magic to
		# make it atomic since `mv -T` is not portable
		rm -rf "${linktmp}"
		mkdir -p "${linktmp}"
		ln -sf "${target}" "${linktmp}/${linkname}"
		mv "${linktmp}/${linkname}" "${linktmp}/../"
		rmdir "${linktmp}"
	else
		# `ln` will expand into unlink();symlink(); which
		# is not atomic for a small amount of time, but
		# `mv` is a single rename() call
		ln -sf "${target}" "${linktmp}"
		mv "${linktmp}" "${linkfull}"
	fi
}

setup_env() {
	unset TARGET VER LIBPATH
	source "${ENV_D}/${PROFILE}"
	if [[ -z ${TARGET} ]] ; then
		eerror "${PROFILE} is invalid (no \$TARGET defined) :("
		return 1
	fi
	if [[ -z ${VER} ]] ; then
		eerror "${PROFILE} is invalid (no \$VER defined) :("
		return 1
	fi

	#
	# Generate binary symlinks
	#
	BINPATH=""
	BINPATH_LINKS=""
	if [[ ${TARGET} != ${HOST} ]] ; then
		#
		# Newer paths: /usr/${HOST}/${TARGET}/...
		# Older paths: /usr/${TARGET}/...
		#
		if [[ -d "${EROOT}"/usr/${HOST}/${TARGET}/binutils-bin/${VER} ]] ; then
			BINPATH="${EPREFIX}"/usr/${HOST}/${TARGET}/binutils-bin/${VER}
			BINPATH_LINKS="${EPREFIX}"/usr/libexec/gcc/${TARGET}
		fi
	fi
	if [[ -z ${BINPATH} ]] ; then
		BINPATH="${EPREFIX}"/usr/${TARGET}/binutils-bin/${VER}
		BINPATH_LINKS="${EPREFIX}"/usr/${TARGET}/bin
	fi
}

# Lists of headers that various versions have installed.
HEADERS=(
	ansidecl.h bfd.h bfdlink.h demangle.h dis-asm.h dyn-string.h
	fibheap.h hashtab.h libiberty.h objalloc.h plugin-api.h
	splay-tree.h symcat.h
)

switch_profile() {
	local x

	ebegin "Switching to ${PROFILE}"

	setup_env || return 1

	cd "${ROOT}/${BINPATH}" || exit 1
	mkdir -p "${ROOT}/${BINPATH_LINKS}" "${EROOT}/usr/bin"
	for x in * ; do
		atomic_ln "${BINPATH}/${x}" "${ROOT}/${BINPATH_LINKS}" "${x}"
		atomic_ln "${BINPATH_LINKS}/${x}" "${EROOT}/usr/bin" "${TARGET}-${x}"
		if [[ ${TARGET} == ${HOST} ]] ; then
			atomic_ln "${TARGET}-${x}" "${EROOT}/usr/bin" "${x}"
		fi
	done

	#
	# Generate library / ldscripts symlinks
	#
	: ${LIBPATH:=${EPREFIX}/usr/lib/binutils/${TARGET}/${VER}}
	cd "${ROOT}/${LIBPATH}" || exit 1
	if [[ ${TARGET} == ${HOST} ]] ; then
		dstlib=${EROOT}/usr/${HOST}/lib
	else
		dstlib=${EROOT}/usr/${HOST}/${TARGET}/lib
	fi
	# When upgrading, we need to clean up ldscripts and libs.
	# Don't symlink back in the libs -- the binutils-lib package handles
	# these now.
	# TODO: Stop requiring even the ldscripts symlink.
	mkdir -p "${dstlib}"
	rm -rf "${ROOT}/${BINPATH_LINKS}"/ldscripts
	atomic_ln "${LIBPATH}/ldscripts" "${dstlib}" "ldscripts"
	find -L "${dstlib}" -xtype l -name 'lib*' -delete
	# Detect older binutils w/broken rpaths. #562460
	# We can hardcode the "/lib" part since that's what the binutils
	# configure scripts have.  They did not include any other path.
	if [[ $(scanelf -qF '%r#F' "${ROOT}/${BINPATH}/as") == */lib ]] ; then
		ewarn "Old cross-binutils detected; please re-emerge to fix (see bug #562460)."
		for x in lib* ; do
			atomic_ln "${LIBPATH}/${x}" "${dstlib}" "${x}"
		done
	fi

	#
	# Clean out old generated include symlinks
	#
	INCPATH=${LIBPATH}/include
	if [[ -d ${ROOT}/${INCPATH} ]] ; then
		cd "${ROOT}/${INCPATH}" || exit 1
		if [[ ${HOST} == ${TARGET} ]] ; then
			# The binutils-lib package handles these files now.
			for x in libiberty "${HEADERS[@]}" ; do
				x="${EROOT}/usr/include/${x}"
				if [[ -L ${x} ]] ; then
					rm "${x}"
				fi
			done
		else
			# Clean out old path -- cannot use '-exec {} +' syntax here
			find . -type f -exec rm -f "${EROOT}/usr/${TARGET}/usr/include/{}" \;
			rmdir "${EROOT}/usr/${TARGET}/usr/include" >& /dev/null
			rmdir "${EROOT}/usr/${TARGET}/usr" >& /dev/null
			rmdir "${EROOT}/usr/${TARGET}" >& /dev/null
		fi
	fi

	#
	# Make sure proper paths get updated
	#
	local env_update_flag="--no-ldconfig"
	if [[ ${TARGET} == ${HOST} ]] ; then
		# Delete old config now that binutils-libs installs these files.
		# Note: This skips ldconfig update if env.d had LDPATH, but meh.
		# Most people have upgraded to ld.so.conf.d, and someone else will
		# eventually re-run ldconfig for us.
		x="${EROOT}"/etc/ld.so.conf.d/05binutils.conf
		if [[ -e ${x} ]]; then
			rm -f "${x}"
			env_update_flag=""
		fi

		DATAPATH="${EPREFIX}"/usr/share/binutils-data/${TARGET}/${VER}
		local e="${EROOT}"/etc/env.d/05binutils
		local ee="${e}.tmp"
		rm -f "${ee}"
		[[ -d ${ROOT}/${DATAPATH}/man  ]] && echo "MANPATH=${DATAPATH}/man"   >> "${ee}"
		[[ -d ${ROOT}/${DATAPATH}/info ]] && echo "INFOPATH=${DATAPATH}/info" >> "${ee}"
		mv_if_diff "${ee}" "${e}"
	fi

	local c="${ENV_D}/config-${TARGET}"
	local cc="${c}.tmp"
	echo "CURRENT=${VER}" > "${cc}"
	mv_if_diff "${cc}" "${c}"

	eend 0

	#
	# Regen env.d if need/can be
	#
	if [[ ${ROOT} == "/" ]] && [[ ${TARGET} == ${HOST} ]] ; then
		env-update ${env_update_flag}
		echo
		ewarn "Please remember to run:"
		echo
		ewarn "  # . ${EPREFIX}/etc/profile"
		echo
	fi

	return 0
}

uninstall_target() {
	: ${TARGET:=${UARG}}

	if [[ ${TARGET} == ${HOST} ]] ; then
		die "refusing to uninstall native binutils"
	fi

	shopt -s nullglob
	PROFILE=""

	for PROFILE in "${ENV_D}"/${TARGET}-* ; do
		ewarn "Removing all signs of ${PROFILE##*/}"
		rm -f "${ENV_D}"/${PROFILE}
	done
	if [[ -z ${PROFILE} ]] && [[ ! -e ${ENV_D}/config-${TARGET} ]] ; then
		die "no profiles exist for '${TARGET}'"
	fi

	rm -f "${ENV_D}"/config-${TARGET}

	local x
	for x in \
		addr2line ar as c++filt dwp elf2flt elfedit flthdr gprof \
		ld ld.{bfd,gold,real} \
		nm objcopy objdump ranlib readelf size strings strip
	do
		x=(
			"${EROOT}"/usr/bin/${TARGET}-${x}
			"${EROOT}"/usr/{${HOST}/,}${TARGET}/bin/${x}
			"${EROOT}"/usr/libexec/gcc/${TARGET}/${x}
		)
		rm -f "${x[@]}"
	done
	for x in "${HEADERS[@]}" ; do
		rm -f "${EROOT}"/usr/{${HOST}/,}${TARGET}/{usr/,}include/${x}
	done
	for x in bfd iberty opcodes ; do
		rm -f "${EROOT}"/usr/${HOST}/${TARGET}/lib/lib${x}{{-*,}.so,.a,.la}
	done
	# Delete broken symlinks
	local destdir="${EROOT}/usr/${HOST}/${TARGET}"
	rm -f "${destdir}"/lib/ldscripts
	find -L "${destdir}"/lib -type l -exec rm {} +
	rmdir \
		"${destdir}"/{bin,include,lib,usr} \
		"${destdir}" \
		"${EROOT}"/var/db/pkg/cross-${TARGET} \
		"${EROOT}"/usr/{${HOST}/,}${TARGET}/bin \
		"${EROOT}"/usr/libexec/gcc/${TARGET} \
		2>/dev/null

	rm -f "${ENV_D}"/${TARGET}-*
}

set_current_profile() {
	if [[ ! -f ${ENV_D}/config-${TARGET} ]] ; then
		eerror "${argv0}: unable to locate a profile for target: ${TARGET}"
		return 1
	fi

	source "${ENV_D}/config-${TARGET}"

	if [[ -z ${CURRENT} ]] ; then
		eerror "${argv0}: no binutils profile is active!"
		return 1
	fi

	echo "${TARGET}-${CURRENT}"

	return 0
}
get_current_profile() { echo "${PROFILE}" ; }

list_profiles() {
	local x i target

	if [[ ${ROOT} != / ]] ; then
		echo "Using binutils-config info in ${ROOT}"
	fi

	set -- "${ENV_D}"/*
	target=
	i=1

	for x ; do
		# skip broken links and config files
		[[ -f ${x} ]] || continue
		[[ ${x} == */config-* ]] && continue

		source "${x}"
		if [[ ${target} != ${TARGET} ]] ; then
			[[ -n ${target} ]] && echo
			target=${TARGET}
		fi

		x=${x##*/}
		if [[ -e ${ENV_D}/config-${TARGET} ]] ; then
			source "${ENV_D}/config-${TARGET}"
			if [[ ${VER} == ${CURRENT} ]] ; then
				[[ ${TARGET} == ${HOST} ]] \
					&& x="${x} ${GOOD}*${NORMAL}" \
					|| x="${x} ${HILITE}*${NORMAL}"
			fi
		fi

		# We would align the [...] field like so:
		#printf ' [%*ss] %s\n' ${##} "${i}" "${x}"
		# but this breaks simple scripting: `binutils -l | awk '{print $2}'`

		# Or we could align the target col like so:
		#printf ' [%s]%*s %s\n' "${i}" $(( ${##} - ${#i} )) "" "${x}"
		# but i'm not sold that it looks better

		# So keep it simple ... only makes a diff anyways for crazy people
		# like me which have 100+ binutils packages installed ...
		echo " [$i] ${x}"
		((++i))
	done
}

switch_linker() {
	local bpath ld=$1

	case ${ld} in
	ld.*) ;;
	*) die "not supported: linker must start with 'ld.'" ;;
	esac

	setup_env || return 1
	bpath="${ROOT}/${BINPATH}"

	# does this binutils even support the requested linker ?
	if [[ ! -e ${bpath}/${ld} ]] ; then
		die "sorry, but ${PROFILE} doesn't support the ${ld} linker"
	fi

	# switch it up
	ebegin "Setting default linker to ${ld} for ${PROFILE}"
	atomic_ln ${ld} "${bpath}" ld
	eend $?
}

set_HOST() {
	# Set HOST to CHOST if it isn't already set
	: ${HOST:=${CHOST:-$(portageq envvar CHOST)}}
}

ENV_D="${EROOT}etc/env.d/binutils"

DEBUG="no"
NEED_ACTION="yes"
DOIT="switch_profile"
PROFILE="current"
HOST=""
TARGET=""
unset UARG

select_action() {
	if [[ ${NEED_ACTION} != "no" ]] ; then
		NEED_ACTION="no"
		DOIT=$1
	else
		die "one action at a time!"
	fi
}

while [[ $# -gt 0 ]] ; do
	x=$1
	shift
	case ${x} in
		-c|--get-current-profile)  select_action get_current_profile ;;
		-l|--list|--list-profiles) select_action list_profiles ;;
		-u|--uninstall)            select_action uninstall_target ;;
		--linker)                  select_action "switch_linker $1"; shift ;;
		-d|--debug)                DEBUG="yes" ;;
		-h|--help)                 usage 0 ;;
		-V|--version)
			ver="@PV@"
			echo "binutils-config-${ver/@'PV'@/git}"
			exit 0
			;;
		-*)
			die "invalid switch!  Try '--help'."
			;;
		*)
			if [[ ${UARG+set} == "set" ]] ; then
				die "only one profile/target at a time please"
			fi
			NEED_ACTION="maybe"
			UARG=${x}
			;;
	esac
done

[[ ${NEED_ACTION} == "yes" ]] && usage 1
[[ ${DEBUG} == "yes" ]] && set -x

# All operations need to know the current HOST to figure out
# what is a native target and what is a cross target
set_HOST

# All operations need to know the profile the user wants
case ${DOIT} in
switch_profile|switch_linker_*)
	# decode user's profile choice
	x=${UARG:-$(TARGET=${HOST} set_current_profile)}
	PROFILE=""
	if [[ -z $(echo ${x} | tr -d '[:digit:]') ]] ; then
		# User gave us a # representing the profile
		i=1
		for y in "${ENV_D}"/* ; do
			[[ ${y/config-} != ${y} ]] && continue

			if [[ -f ${y} ]] && [[ ${x} -eq ${i} ]] ; then
				PROFILE=${y##*/}
				break
			fi
			((++i))
		done
	fi

	if [[ -z ${PROFILE} ]] ; then
		# User gave us a full HOST-ver
		x=${x##*/}
		if [[ -f ${ENV_D}/${x} ]] ; then
			# Valid HOST-ver yeah!
			PROFILE=${x}
		else
			# Not a valid HOST-ver ...
			if [[ ! -f ${ENV_D}/config-${x} ]] ; then
				# Maybe they just gave us a ver ...
				if [[ -f ${ENV_D}/${HOST}-${x} ]] ; then
					x=${HOST}-${x}
				else
					die "could not locate '$x' in '${ENV_D}/'!"
				fi
				PROFILE=${x}
			else
				# Maybe they just gave us a target ... pick active profile
				PROFILE=$(TARGET=${x} set_current_profile)
			fi
		fi
	fi
	;;
*)
	# lookup current profile as the user gave us a target
	PROFILE=$(TARGET=${UARG:-${HOST}} set_current_profile) || exit 1
	;;
esac

eval ${DOIT}

# vim:ts=4