grub: replace legacy grub install scripts

Translate old legacy grub scripts into grub.py
Implement ogGrubInstallMbr as install_main_grub() and
ogGrubInstallPartition as install_linux_grub().

Add grub configuration file generator through the classes
GrubConfig and MenuEntry.

Ensure EFI tree structure compatibility with legacy code.
The structure of the created folders in the ESP is non-standard,
efi binaries are usually located in the folder below the EFI/
directory.

Structure used by ogClient:

EFI/
├── grub/
│   └── Boot/
│       ├── BOOTX64.CSV
│       ├── grub.cfg
│       ├── mmx64.efi
│       ├── shimx64.efi
│       ├── BOOTX64.EFI
│       ├── grubx64.efi
│       └── ogloader.efi
...

The function _mangle_efi_folder handles the folder structure after
grub-install to comply with the location expected by ogLive.

install_linux_grub() installs a grub local to each Linux install
to enable chainloading, each grub is located in EFI/Part-xx-yy/ in
UEFI. The local linux BIOS grub in legacy scripts is unreliable,
grub-install reports a failure during the install process.

install_main_grub() installs a global grub in EFI/grub/ to show a
grub menu when the pxe boot fails. The global grub contains entries
to every installed os. No global grub is installed for BIOS
systems, a Boot partition would be required to store the grub
configuration.

1 files changed, 18 insertions, 0 deletions

diff --git a/src/utils/uefi.py b/src/utils/uefi.py
index 27b7ba0..10095a7 100644
--- a/src/utils/uefi.py
+++ b/src/utils/uefi.py
@@ -125,6 +125,24 @@ def efibootmgr_create_bootentry(disk, part, loader, label, add_to_bootorder=True
     except OSError as e:
         raise OgError(f'Unexpected error adding boot entry to nvram. UEFI firmware might be buggy') from e
 
+def efibootmgr_set_entry_order(label, position):
+    logging.info(f'Setting {label} entry to position {position} of boot order')
+    boot_info = run_efibootmgr_json(validate=False)
+    boot_entries = boot_info.get('vars', [])
+    boot_order = boot_info.get('BootOrder', [])
+
+    entry = _find_bootentry(boot_entries, label)
+    target_grub_entry = _strip_boot_prefix(entry)
+
+    if target_grub_entry in boot_order:
+        boot_order.remove(target_grub_entry)
+
+    boot_order.insert(position, target_grub_entry)
+
+    try:
+        proc = subprocess.run([EFIBOOTMGR_BIN, "-o", ",".join(boot_order)], check=True, text=True)
+    except OSError as e:
+        raise OgError(f'Unexpected error setting boot order to NVRAM. UEFI firmware might be buggy') from e
 
 def _find_efi_loader(loader_paths):
     for efi_app in loader_paths: