1 files changed, 60 insertions, 0 deletions
diff --git a/nixos/modules/installer/tools/nixos-enter.sh b/nixos/modules/installer/tools/nixos-enter.sh
new file mode 100644
index 000000000000..679391189612
--- /dev/null
+++ b/nixos/modules/installer/tools/nixos-enter.sh
@@ -0,0 +1,60 @@
+#! @shell@
+
+set -e
+
+# Re-exec ourselves in a private mount namespace so that our bind
+# mounts get cleaned up automatically.
+if [ -z "$NIXOS_ENTER_REEXEC" ]; then
+    export NIXOS_ENTER_REEXEC=1
+    if [ "$(id -u)" != 0 ]; then
+        extraFlags="-r"
+    fi
+    exec unshare --fork --mount --uts --mount-proc --pid $extraFlags -- "$0" "$@"
+else
+    mount --make-rprivate /
+fi
+
+mountPoint=/mnt
+system=/nix/var/nix/profiles/system
+command=($system/sw/bin/bash "--login")
+
+while [ "$#" -gt 0 ]; do
+    i="$1"; shift 1
+    case "$i" in
+        --root)
+            mountPoint="$1"; shift 1
+            ;;
+        --system)
+            system="$1"; shift 1
+            ;;
+        --help)
+            exec man nixos-enter
+            exit 1
+            ;;
+        --command|-c)
+            command=($system/sw/bin/bash "-c" "$1")
+            shift 1
+            ;;
+        --)
+            command=("$@")
+            break
+            ;;
+        *)
+            echo "$0: unknown option \`$i'"
+            exit 1
+            ;;
+    esac
+done
+
+if [[ ! -e $mountPoint/etc/NIXOS ]]; then
+    echo "$0: '$mountPoint' is not a NixOS installation" >&2
+    exit 126
+fi
+
+mkdir -m 0755 -p "$mountPoint/dev"
+mount --rbind /dev "$mountPoint/dev"
+
+# Run the activation script. Set $LOCALE_ARCHIVE to supress some Perl locale warnings.
+LOCALE_ARCHIVE=$system/sw/lib/locale/locale-archive chroot "$mountPoint" "$system/activate" >&2 || true
+
+exec chroot "$mountPoint" "${command[@]}"