1 files changed, 114 insertions, 0 deletions
diff --git a/nixos/modules/system/boot/loader/gummiboot/gummiboot-builder.py b/nixos/modules/system/boot/loader/gummiboot/gummiboot-builder.py
new file mode 100644
index 000000000000..9ea224b51f63
--- /dev/null
+++ b/nixos/modules/system/boot/loader/gummiboot/gummiboot-builder.py
@@ -0,0 +1,114 @@
+#! @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)