X-Git-Url: https://git.wh0rd.org/?a=blobdiff_plain;f=.bin%2Fcustom-chroot;h=08d76ada03bfa4aedf7429ab16893cb924858bdd;hb=8c29b1d8acfc9935f148a486227c8d2fdb05df37;hp=7c576bb0109d991863791249022402c655c458c0;hpb=f2ff891e6eb173ea0ffc4fed185af8ca1b2e15bd;p=home.git

diff --git a/.bin/custom-chroot b/.bin/custom-chroot
index 7c576bb..08d76ad 100755
--- a/.bin/custom-chroot
+++ b/.bin/custom-chroot
@@ -1,100 +1,181 @@
 #!/bin/bash -e
 
-[[ -w / ]] || exec sudo env HOME="$HOME" "$0" "$@"
+bootstrap() {
+	[[ $(id -u) -eq 0 ]] || exec sudo env -uUNSHARE HOME="$HOME" "$0" "$@"
 
-if [[ -z ${UNSHARE} ]] ; then
-	mount_args=
-	if type -P unshare >&/dev/null ; then
-		UNSHARE=true exec unshare -m -- "$0" "$@"
+	if [[ -z ${UNSHARE} ]] ; then
+		mount_args=
+		if type -P unshare >&/dev/null ; then
+			test_arg() { unshare "$@" -- true >&/dev/null && uargs+=( "$@" ) || :; }
+			uargs=( -m )
+			test_arg -u
+			test_arg -i
+			test_arg -p -f --mount-proc
+			test_arg --propagation=private
+			UNSHARE=true exec unshare "${uargs[@]}" -- "$0" "$@"
+		fi
+	else
+		mount_args='-n'
 	fi
-else
-	mount_args='-n'
-fi
-unset UNSHARE
-
-mounts="proc sys dev dev/pts usr/portage usr/portage/distfiles"
-
-chroot=${0%/*}
-case ${chroot} in
-	.) chroot=${PWD} ;;
-	./*) chroot=${PWD}/${chroot#./} ;;
-esac
-cd "${chroot}"
-
-do_umount() {
-	mounts=$(mount | grep ${chroot} | awk '{print $3}' | tac)
-	for m in ${mounts} ; do
-		echo "unmounting $m"
-		umount $m
-	done
-	if [[ -z ${mounts} ]] ; then
-		echo "nothing mounted in ${chroot}"
-	fi
-	exit 0
+	unset UNSHARE
 }
 
-while [[ -n $1 ]] ; do
-	case $1 in
-		-u) do_umount ;;
-		-*) echo "unknown option $1"; exit 1 ;;
-		*)  break ;;
-	esac
-done
+is_mounted() {
+	local dst=$1
+	grep -sq "${dst}" /proc/mounts
+}
 
 maybe_mount() {
 	local src=/$1 dst=${chroot}/${2:-$1}
 	[[ -d ${src} ]] || return 0
-	mkdir -p "${dst}"
-	grep -sq "${dst}" /proc/mounts || mount ${mount_args} --bind "${src}" "${dst}"
+	if ! mkdir -p "${dst}" ; then
+		[[ -w ${chroot} ]] && exit 1 || return 0
+	fi
+	is_mounted "${dst}" || mount ${mount_args} --bind "${src}" "${dst}"
 }
-for m in ${mounts} ; do
-	maybe_mount ${m}
-done
 
 get_type() {
 	case $(file "$1") in
-		*x86-64*)         echo x86_64;;
-		*"Intel 80386"*)  echo i386;;
-		*32-bit*PowerPC*) echo ppc;;
-		*64-bit*PowerPC*) echo ppc64;;
+	*x86-64*)             echo x86_64;;
+	*"Intel 80386"*)      echo i386;;
+	*32-bit*PowerPC*MSB*) echo ppc;;
+	*64-bit*PowerPC*MSB*) echo ppc64;;
+	*32-bit*PowerPC*LSB*) echo ppcle;;
+	*64-bit*PowerPC*LSB*) echo ppc64le;;
+	*32-bit*S/390*)       echo s390;;
+	*64-bit*S/390*)       echo s390x;;
+	*64-bit*MIPS*)        echo mips64;;
+	*32-bit*MIPS*N32*)    echo mips64;;
+	*32-bit*MIPS*)        echo mips;;
+	*32-bit*PA-RISC*)     echo parisc;;
+	*64-bit*PA-RISC*)     echo parisc64;;
+	*32-bit*SPARC*)       echo sparc;;
+	*64-bit*SPARC*)       echo sparc64;;
 	esac
 }
-bin_dst=$(get_type bin/bash)
-setarch=
-if [[ -n ${bin_dst} ]] && type -P setarch &>/dev/null ; then
-	setarch="setarch ${bin_dst}"
-fi
-
-if [[ ! -L etc/mtab ]] ; then
-	rm -f etc/mtab
-	ln -sf /proc/mounts etc/mtab
-fi
-etc="
-	hosts
-	locale.gen
-	localtime
-	resolv.conf
-"
-home="
-	.inputrc
-	.gdbinit
-	.gitconfig
-	.nanorc
-"
-for f in \
-	$(printf 'etc/%s ' ${etc}) \
-; do
-	if [ -e "/${f}" ] ; then
-		cp /${f} ${f}
+
+init_chroot() {
+	[[ -w . ]] || return 0
+
+	if [[ ! -L etc/mtab ]] ; then
+		ln -sfT /proc/mounts etc/mtab
+	fi
+	local f dst
+	local etc=(
+		hosts
+		locale.gen
+		localtime
+		resolv.conf
+	)
+	local home=(
+		.inputrc
+		.gdbinit
+		.gitconfig
+		.nanorc
+	)
+	for f in \
+		$(printf 'etc/%s ' "${etc[@]}") \
+	; do
+		if [[ -e /${f} ]] ; then
+			cp "/${f}" "${f}"
+		fi
+	done
+	for f in "${home[@]}" ; do
+		df="root/${f}"
+		f="${HOME}/${f}"
+		if [[ -e ${f} ]] ; then
+			cp "${f}" "${df}"
+		fi
+	done
+
+	if [[ ! -d root/.git ]] ; then
+		f="${HOME}/.profile.d/aliases.sh"
+		if [[ -e ${f} ]] ; then
+			cat "${f}" > root/.bash_profile
+		fi
 	fi
-done
-for f in ${home} ; do
-	cp ~/${f} root/${f}
-done
-
-unset LS_COLORS # format changes over time
-[[ $# -eq 0 ]] && set -- env HOME=/root /bin/bash -l
-exec \
-	${setarch} \
-	chroot "${chroot}" \
-	"$@"
+}
+
+usage() {
+	cat <<-EOF
+	Usage: ${0##*/} [options] [program to run]
+
+	Sets up common mount points and then chroots in and runs a program.
+	If no program is specified, then launch a login shell.
+
+	Options:
+	  -u          Unmount all paths in the chroot
+	  -m <path>   Add path to mount list
+	  -d <dir>    Use <dir> as chroot (defaults to ${0%/*})
+	  -h          This help screen
+	EOF
+	exit
+}
+
+main() {
+	bootstrap "$@"
+
+	local mounts=(
+		proc sys tmp dev dev/shm run
+		usr/portage usr/portage/distfiles
+		var/db/repos/gentoo var/cache/distfiles
+		usr/local/src
+	)
+
+	local chroot=${0%/*}
+	case ${chroot} in
+	.) chroot=${PWD} ;;
+	./*) chroot=${PWD}/${chroot#./} ;;
+	esac
+
+	local cmd
+	while [[ -n $1 ]] ; do
+		case $1 in
+		-u) cmd='umount' ;;
+		-m) mounts+=( "$2" ); shift ;;
+		-d) chroot=$(realpath "$2"); shift ;;
+		--help|-h) usage ;;
+		-*) echo "${0##*/}: unknown option $1"; exit 1 ;;
+		*)  break ;;
+		esac
+		shift
+	done
+	cd "${chroot}"
+
+	case ${cmd} in
+	umount) exec "${0%/*}/umount-tree" -y "${chroot}" ;;
+	esac
+
+	local m
+	for m in "${mounts[@]}" ; do
+		maybe_mount "${m}"
+	done
+	# Handle special mounts that we don't want to just bind mount.
+	if ! is_mounted "${chroot}/dev/pts" ; then
+		# Option order matters: on older kernels that don't recognize newinstance,
+		# parsing stops as soon as it hits that.
+		mount -t devpts devpts "${chroot}/dev/pts" \
+			-o nosuid,noexec,mode=0620,gid=5,ptmxmode=0666,newinstance
+	fi
+
+	init_chroot
+
+	local setarch
+	if type -P setarch &>/dev/null ; then
+		local bin_dst=$(get_type bin/bash)
+		if [[ -n ${bin_dst} ]] ; then
+			setarch="setarch ${bin_dst}"
+		fi
+	fi
+
+	# Doubtful these settings we want to leak into the chroot.
+	unset ROOT PORTAGE_CONFIGROOT LD_LIBRARY_PATH
+	unset LS_COLORS # format changes over time
+	[[ $# -eq 0 ]] && set -- env HOME=/root /bin/bash -l
+	exec \
+		${setarch} \
+		chroot "${chroot}" \
+		"$@"
+}
+
+main "$@"