subspace-run

#!/bin/bash
set -euo pipefail

SUBSPACE_DIR="/subspace"
XDG_RUNTIME_DIR="${XDG_RUNTIME_DIR:-/run/user/$UID}"

if [ "$EUID" -ne 0 ]; then
    echo "This command requires superuser privileges."
    exit 1
fi

if [ $# -lt 2 ]; then
    echo "Usage: subspace-run <subspace> <command> [args...]" >&2
    echo "" >&2
    echo "Available subspaces:" >&2
    for d in "$SUBSPACE_DIR"/*/; do
        [ -d "$d/usr" ] && echo "  $(basename "$d")" >&2
    done
    exit 1
fi

subspace="$1"
shift
root="$SUBSPACE_DIR/$subspace"

if [ ! -d "$root" ]; then
    echo "Error: Subspace '$subspace' not found at $root" >&2
    exit 1
fi

if ! command -v bwrap &>/dev/null; then
    echo "Error: bubblewrap (bwrap) not found." >&2
    echo "Install: sudo pacman -S bubblewrap" >&2
    exit 1
fi

bwrap_args=(
    --bind "$root" /
    --dev-bind /dev /dev
    --dev-bind /dev/dri /dev/dri
    --proc /proc
    --ro-bind /sys /sys
    --ro-bind /tmp/.X11-unix /tmp/.X11-unix
    --tmpfs /dev/shm
    --setenv HOME /root
    --setenv PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
    --unshare-ipc
    --unshare-pid
    --unshare-uts
)

if [ -f "$root/etc/resolv.conf" ]; then
    bwrap_args+=(--ro-bind /etc/resolv.conf /etc/resolv.conf)
fi

for d in /usr/lib/dri /usr/lib/xorg/modules/dri; do
    [ -d "$d" ] && bwrap_args+=(--ro-bind "$d" "$d")
done


if [ -n "${DISPLAY:-}" ]; then
    bwrap_args+=(--setenv DISPLAY "$DISPLAY")
fi

if [ -n "${WAYLAND_DISPLAY:-}" ]; then
    wayland_socket="$XDG_RUNTIME_DIR/$WAYLAND_DISPLAY"
    if [ -S "$wayland_socket" ]; then
        bwrap_args+=(--ro-bind "$wayland_socket" "$wayland_socket")
        bwrap_args+=(--setenv WAYLAND_DISPLAY "$WAYLAND_DISPLAY")
        bwrap_args+=(--setenv XDG_RUNTIME_DIR "$XDG_RUNTIME_DIR")
    fi
fi

if [ -S "$XDG_RUNTIME_DIR/bus" ]; then
    bwrap_args+=(--ro-bind "$XDG_RUNTIME_DIR/bus" "$XDG_RUNTIME_DIR/bus")
    bwrap_args+=(--setenv DBUS_SESSION_BUS_ADDRESS "unix:path=$XDG_RUNTIME_DIR/bus")
fi

exec bwrap "${bwrap_args[@]}" "$@"