Rename tmpdir to target and always preserve it, dropping --preserve

There is nothing temporary about our "tmpdir" - its sole purpose is to
contain the final product of the bootstrap process. Thus, removing it
at the end of bootstrap amounts to doing the entire process for nothing.

To remedy this, --tmpdir is renamed --target, keeping the -t short form,
and defaulting to "target" instead of "tmp" to make its purpose clearer.
The --preserve option is removed, as the target is now always preserved.

lib/tmpdir.py

@@ -1,101 +0,0 @@
-#!/usr/bin/env python3
-
-# SPDX-FileCopyrightText: 2023 fosslinux <fosslinux@aussies.space>
-# SPDX-License-Identifier: GPL-3.0-or-later
-
-"""
-Contains a class that represents a tmpdir
-"""
-
-import enum
-import getpass
-import os
-import shutil
-
-from lib.utils import mount, umount, create_disk, run_as_root
-
-class TmpType(enum.Enum):
-    """Different types of tmpdirs we can have"""
-    NONE = 0
-    TMPFS = 1
-
-class Tmpdir:
-    """
-    Represents a tmpdir
-    """
-
-    _disks = {}
-    _disk_filesystems = {}
-    _mountpoints = {}
-
-    def __init__(self, preserve, path="tmp"):
-        self.path = os.path.abspath(path)
-        self.preserve = preserve
-        self._type = TmpType.NONE
-
-        if not os.path.exists(self.path):
-            os.mkdir(self.path)
-
-    def __del__(self):
-        for path in self._mountpoints:
-            print(f"Unmounting {path}")
-            umount(path)
-
-        if not self.preserve:
-            for disk in self._disks.values():
-                print(f"Detaching {disk}")
-                run_as_root("losetup", "-d", disk)
-
-            if self._type == TmpType.TMPFS:
-                print(f"Unmounting tmpdir from {self.path}")
-                umount(self.path)
-
-            print(f"Removing {self.path}")
-            shutil.rmtree(self.path, ignore_errors=True)
-
-    def tmpfs(self, size="8G"):
-        """Mount a tmpfs"""
-        print(f"Mounting tmpfs on {self.path}")
-        mount("tmpfs", self.path, "tmpfs", f"size={size}")
-        self._type = TmpType.TMPFS
-
-    # pylint: disable=too-many-arguments
-    def add_disk(self,
-                 name,
-                 size="16G",
-                 filesystem="ext4",
-                 tabletype="msdos",
-                 bootable=False,
-                 mkfs_args=None):
-        """Add a disk"""
-        disk_path = os.path.join(self.path, f"{name}.img")
-        self._disks[name] = create_disk(disk_path,
-                                        tabletype,
-                                        filesystem,
-                                        size,
-                                        bootable,
-                                        mkfs_args)
-        self._disk_filesystems[name] = filesystem
-        # Allow executing user to access it
-        run_as_root("chown", getpass.getuser(), self._disks[name])
-
-    def mount_disk(self, name, mountpoint=None):
-        """Mount the disk"""
-        if mountpoint is None:
-            mountpoint = f"{name}_mnt"
-        mountpoint = os.path.join(self.path, mountpoint)
-        os.mkdir(mountpoint)
-        mount(self._disks[name] + "p1", mountpoint, self._disk_filesystems[name])
-        # Allow executing user to access it
-        run_as_root("chown", getpass.getuser(), mountpoint)
-        self._mountpoints[name] = mountpoint
-        return mountpoint
-
-    def umount_disk(self, name):
-        """Unmount a disk"""
-        umount(self._mountpoints[name])
-        del self._mountpoints[name]
-
-    def get_disk(self, name):
-        """Get the path to a device of a disk"""
-        return self._disks.get(name)