bootstrap-initrd

init.sh (4857B)

#!/bin/oksh
# bootstrap-initrd: Linux initrd to bootstrap from a small binary seed
# SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
# SPDX-License-Identifier: MPL-2.0
set -ex -o pipefail
die() {
	echo "die: $*"
	rescueshell
}
rescueshell() {
	exec $SHELL -l
}
profile_export() {
	export "$@"
	echo "export '$@'" >>/etc/profile
}
build_awk() {
	cd /src/awk-*/
	yacc -d -b awkgram awkgram.y
	pdpmake -e HOSTCC=$CC
	cp -p a.out /bin/awk
}
build_stubs() {
	for i in ls grep cp getty mount reboot
	do
		$CC $CFLAGS -o "/bin/$i" "/src/${i}-stub.c" || die "Failed compiling $i stub"
	done
}
build_stubs_symlinks() {
	ln -s grep /bin/egrep || die
	ln -s grep /bin/fgrep || die
	ln -s cat /bin/sort || die
}
build_pdpmake() {
	cd /src/pdpmake-*/
	$CC $CFLAGS -o /bin/pdpmake *.c
}
build_bzip2() {
	cd /src/bzip2-*/
	pdpmake -f Makefile-libbz2_so CC=$CC || die
	ln -s libbz2.so.1.0.8 libbz2.so
	pdpmake -f Makefile bzip2 CC=$CC || die
	ln libbz2.so.1.0.8 /lib/libbz2.so.1.0.8
	ln -s libbz2.so.1.0.8 /lib/libbz2.so
	ln -s libbz2.so.1.0.8 /lib/libbz2.so.1.0
	ln bzip2 /bin/bzip2
	ln -s bzip2 /bin/bunzip2
	ln -s bzip2 /bin/bzcat
	pdpmake clean
}
build_zlib_libs() {
	cd /src/zlib-*/
	./configure --prefix=/usr </dev/null
	# generate crc32.h
	pdpmake crc32 CFLAGS="${CFLAGS} -DMAKECRCH"
	./crc32
	pdpmake check
	pdpmake install
	pdpmake clean
}
build_pigz() {
	cd /src/pigz-*/
	# Makefile placeholders for zopfli/deflate.h and zopfli/util.h
	touch deflate.h util.h
	pdpmake CC=$CC ZOP= ZOPFLI= CFLAGS="${CFLAGS} -DNOZOPFLI"
	cp -p pigz /bin
	ln -s pigz /bin/unpigz
	ln -s pigz /bin/gzip
	ln -s pigz /bin/ungzip
	pdpmake clean
}
build_hierloom_devtools_m4() {
	cd /src/heirloom-devtools-*/m4/
	$YACC -o m4y.c m4y.y
	$CC $CFLAGS -D_GNU_SOURCE m4.c m4ext.c m4macs.c m4y.c version.c -o /bin/m4
}
build_hierloom_devtools() {
	cd /src/heirloom-devtools-*/
	for cmd in lex
	do
		pdpmake "$cmd"/Makefile
		pdpmake -C "$cmd" RANLIB=true
		pdpmake -C "$cmd" RANLIB=true install
		pdpmake -C "$cmd" RANLIB=true clean
	done
}
build_hierloom() {
	cd /src/heirloom/
	mkdir -p /usr/5bin /usr/5lib /etc/default /usr/5bin/s42 /usr/5bin/posix2001 /usr/ucb/
	for cmd in libcommon diff tar sort comm find stty
	do
		pdpmake "$cmd"/Makefile
		pdpmake -C "$cmd" CC=$CC AR="ar" RANLIB=true
		pdpmake -C "$cmd" CC=$CC AR="ar" RANLIB=true install
		pdpmake -C "$cmd" CC=$CC AR="ar" RANLIB=true clean
	done
	ln -fs /usr/5bin/sort /bin/sort
	mv /usr/5bin/find /usr/bin/find
}
build_utils_std() {
	cd /src/utils-std-*/
	oldpath="$PATH"
	export PATH="$PATH:$PWD/cmd/"
	pdpmake -f bootstrap.mk || die
	MAKE=pdpmake oksh ./configure PREFIX=/usr || die
	pdpmake || die
	pdpmake selfcheck || die
	pdpmake install || die
	pdpmake clean || die
	export PATH="$oldpath"
}
build_sbase() {
	cd /src/sbase-*/
	for i in ed sed
	do
		$CC -D_DEFAULT_SOURCE -D_NETBSD_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700 -D_FILE_OFFSET_BITS=64 -Os -o "/bin/${i}" "${i}.c" libutil/*.c libutf/*.c
	done
}
build_oyacc() {
	cd /src/yacc-oyacc-*/
	# config.h wrote in make-root.sh due to lack of cat
	$CC $CFLAGS \
		-D_GNU_SOURCE -D__unused= \
		-o /bin/yacc *.c
}
export CC=tcc
export CFLAGS="-Os -Wall -Wextra"
build_oyacc
export SHELL="/bin/oksh"
export YACC="yacc"
build_pdpmake || die
build_sbase || die
# stubs for utilities currently missing from utils-std
build_stubs || die
build_hierloom_devtools_m4 || die
build_utils_std || die
export MAKEFLAGS="-j$(nproc)"
profile_export PATH="/bin:/usr/bin:/usr/local/bin"
profile_export YACC="yacc"
profile_export STRIP="true"
profile_export INSTALL="install"
profile_export AR="ar"
# re-export due to prior lack of echo
profile_export CC="$CC"
profile_export CFLAGS="$CFLAGS"
# needs: make cat $CC $YACC rm mv $AR true test install mkdir
build_hierloom_devtools </dev/null || die
cat >/bin/hostname <<'EOF'
#!/bin/sh
exec uname -n
EOF
chmod +x /bin/hostname
build_stubs_symlinks || die
build_awk || die
build_hierloom || die
build_bzip2 || die
# Needs /bin/rm
build_zlib_libs </dev/null || die
build_pigz || die
test -f /cacert-*.pem && {
	mkdir -p /usr/share/cacert/ || die
	mv /cacert-*.pem /usr/share/cacert/cert.pem || die
	mkdir -p /etc/ssl || die
	ln -s /usr/share/cacert/cert.pem /etc/ssl/cert.pem || die
}
mkdir -p $HOME
cd
if [ "$(date +%Y)" = 1970 ]; then
	/etc/setdate.sh
fi
# No /dev/tty1, no getty (as seen in containers)
if ! test -e /dev/tty1
then
	times
	echo 'Done bootstrapping! Dropping into a shell'
	exec /bin/sh -l
fi
cat /proc/uptime
echo 'Done bootstrapping! Dropping into a TTY'
if ! grep -q console= /proc/cmdline
then
	getty "/dev/tty1" /bin/sh -l &
else
	for arg in $(cat /proc/cmdline); do
		case $arg in
			console=*)
				target=${arg#console=}
				device=${target%,*}
				# baud=${target#*,}
				getty "/dev/${device}" /bin/sh -l &
			;;
		esac
	done
fi
wait