nixpkgs/nixos/modules/system/boot/loader/gummiboot/gummiboot-builder.py

114 lines
4.1 KiB
Python

#! @python@/bin/python
import argparse
import shutil
import os
import errno
import subprocess
import glob
import tempfile
import errno
def copy_if_not_exists(source, dest):
known_paths.append(dest)
if not os.path.exists(dest):
shutil.copyfile(source, dest)
system_dir = lambda generation: "/nix/var/nix/profiles/system-%d-link" % (generation)
def write_entry(generation, kernel, initrd):
entry_file = "@efiSysMountPoint@/loader/entries/nixos-generation-%d.conf" % (generation)
generation_dir = os.readlink(system_dir(generation))
tmp_path = "%s.tmp" % (entry_file)
kernel_params = "systemConfig=%s init=%s/init " % (generation_dir, generation_dir)
with open("%s/kernel-params" % (generation_dir)) as params_file:
kernel_params = kernel_params + params_file.read()
with open(tmp_path, 'w') as f:
print >> f, "title NixOS"
print >> f, "version Generation %d" % (generation)
if machine_id is not None: print >> f, "machine-id %s" % (machine_id)
print >> f, "linux %s" % (kernel)
print >> f, "initrd %s" % (initrd)
print >> f, "options %s" % (kernel_params)
os.rename(tmp_path, entry_file)
def write_loader_conf(generation):
with open("@efiSysMountPoint@/loader/loader.conf.tmp", 'w') as f:
if "@timeout@" != "":
print >> f, "timeout @timeout@"
print >> f, "default nixos-generation-%d" % (generation)
os.rename("@efiSysMountPoint@/loader/loader.conf.tmp", "@efiSysMountPoint@/loader/loader.conf")
def copy_from_profile(generation, name):
store_file_path = os.readlink("%s/%s" % (system_dir(generation), name))
suffix = os.path.basename(store_file_path)
store_dir = os.path.basename(os.path.dirname(store_file_path))
efi_file_path = "/efi/nixos/%s-%s.efi" % (store_dir, suffix)
copy_if_not_exists(store_file_path, "@efiSysMountPoint@%s" % (efi_file_path))
return efi_file_path
def add_entry(generation):
efi_kernel_path = copy_from_profile(generation, "kernel")
efi_initrd_path = copy_from_profile(generation, "initrd")
write_entry(generation, efi_kernel_path, efi_initrd_path)
def mkdir_p(path):
try:
os.makedirs(path)
except OSError as e:
if e.errno != errno.EEXIST or not os.path.isdir(path):
raise
def get_generations(profile):
gen_list = subprocess.check_output([
"@nix@/bin/nix-env",
"--list-generations",
"-p",
"/nix/var/nix/profiles/%s" % (profile)
])
gen_lines = gen_list.split('\n')
gen_lines.pop()
return [ int(line.split()[0]) for line in gen_lines ]
def remove_old_entries(gens):
slice_start = len("@efiSysMountPoint@/loader/entries/nixos-generation-")
slice_end = -1 * len(".conf")
for path in glob.iglob("@efiSysMountPoint@/loader/entries/nixos-generation-[1-9]*.conf"):
try:
gen = int(path[slice_start:slice_end])
if not gen in gens:
os.unlink(path)
except ValueError:
pass
for path in glob.iglob("@efiSysMountPoint@/efi/nixos/*"):
if not path in known_paths:
os.unlink(path)
parser = argparse.ArgumentParser(description='Update NixOS-related gummiboot files')
parser.add_argument('default_config', metavar='DEFAULT-CONFIG', help='The default NixOS config to boot')
args = parser.parse_args()
# We deserve our own env var!
if os.getenv("NIXOS_INSTALL_GRUB") == "1":
if "@canTouchEfiVariables@" == "1":
subprocess.check_call(["@gummiboot@/bin/gummiboot", "--path=@efiSysMountPoint@", "install"])
else:
subprocess.check_call(["@gummiboot@/bin/gummiboot", "--path=@efiSysMountPoint@", "--no-variables", "install"])
known_paths = []
mkdir_p("@efiSysMountPoint@/efi/nixos")
mkdir_p("@efiSysMountPoint@/loader/entries")
try:
with open("/etc/machine-id") as machine_file:
machine_id = machine_file.readlines()[0]
except IOError as e:
if e.errno != errno.ENOENT:
raise
machine_id = None
gens = get_generations("system")
for gen in gens:
add_entry(gen)
if os.readlink(system_dir(gen)) == args.default_config:
write_loader_conf(gen)
remove_old_entries(gens)