#!/bin/sh
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c) 2021 The FreeBSD Foundation
# All rights reserved.
#
# This software was developed by Konstantin Belousov <kib@FreeBSD.org>
# under sponsorship from the FreeBSD Foundation.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
set -e
${CC} -x assembler-with-cpp -DLOCORE -fPIC -nostdinc -c \
-o sigtramp.pico -I. -I"${S}" -include opt_global.h \
"${S}"/amd64/amd64/sigtramp.S
# We need to make vdso as compact as possible, for it to leave space
# for other things in the shared page. For this, we pack everything
# into single loadable segment.
#
# -z rodynamic is undocumented lld-specific option, seemingly required
# for lld to avoid putting dynamic into dedicated writeable segment,
# despite ldscript placement. It is ignored by ld.bfd but ldscript
# alone is enough there.
#
${LD} --shared -Bsymbolic -soname="elf-vdso.so.1" \
-T "${S}"/conf/vdso_amd64.ldscript \
--eh-frame-hdr --no-undefined -z rodynamic -z norelro -nmagic \
--hash-style=sysv --fatal-warnings --strip-all \
-o elf-vdso.so.1 sigtramp.pico
if [ "$(wc -c elf-vdso.so.1 | ${AWK} '{print $1}')" -gt 2048 ]
then
echo "elf-vdso.so.1 too large" 1>&2
exit 1
fi
if [ -n "$(${ELFDUMP} -d elf-vdso.so.1 | \
${AWK} '/DT_REL.*SZ/{print "RELOCS"}')" ]
then
echo "elf-vdso.so.1 contains runtime relocations" 1>&2
exit 1
fi
${CC} ${DEBUG} -x assembler-with-cpp -DLOCORE -fPIC -nostdinc -c \
-o elf-vdso.so.o -I. -I"${S}" -include opt_global.h \
-DVDSO_NAME=elf_vdso_so_1 -DVDSO_FILE=\"elf-vdso.so.1\" \
"${S}"/tools/vdso_wrap.S
${NM} -D elf-vdso.so.1 | \
${AWK} '/__vdso_sigcode/{printf "#define VDSO_SIGCODE_OFFSET 0x%s\n",$1}' \
>vdso_offsets.h
