ukify: switch from zstd to zstandard

The zstd library does not support stream decompression, and it
requires the zstd header to contain extra metadata, that the kernel
build does not append:

$ file -k vmlinuz-6.13+unreleased-cloud-arm64
vmlinuz-6.13+unreleased-cloud-arm64: PE32+ executable (EFI application) Aarch64 (stripped to external PDB), for MS Windows, 2 sections\012- data
$ ukify build --linux vmlinuz-6.13+unreleased-cloud-arm64 --initrd /boot/initrd.img-6.12.12-amd64 --output uki
Kernel version not specified, starting autodetection 😖.
Real-Mode Kernel Header magic not found
+ readelf --notes vmlinuz-6.13+unreleased-cloud-arm64
readelf: Error: Not an ELF file - it has the wrong magic bytes at the start
Traceback (most recent call last):
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 2508, in <module>
    main()
    ~~~~^^
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 2497, in main
    make_uki(opts)
    ~~~~~~~~^^^^^^
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 1326, in make_uki
    opts.uname = Uname.scrape(linux, opts=opts)
                 ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 382, in scrape
    version = func(filename, opts=opts)
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 372, in scrape_generic
    text = maybe_decompress(filename)
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 219, in maybe_decompress
    return get_zboot_kernel(f)
  File "/home/bluca/git/systemd/src/ukify/ukify.py", line 199, in get_zboot_kernel
    return cast(bytes, zstd.uncompress(f.read(size)))
                       ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^
zstd.Error: Input data invalid or missing content size in frame header.

This appears to be by design:

https://github.com/sergey-dryabzhinsky/python-zstd/issues/53

Switch to python3-zstandard, which works.

diff --git a/src/ukify/ukify.py b/src/ukify/ukify.py
index 9013e64b62da582ca04a92f1c061695b33a5d081..85b8d612f52467db3b97ef61e7ad34e8f9021e81 100755 (executable)
--- a/src/ukify/ukify.py
+++ b/src/ukify/ukify.py
@@ -195,8 +195,8 @@ def get_zboot_kernel(f: IO[bytes]) -> bytes:
     elif comp_type.startswith(b'xzkern'):
         raise NotImplementedError('xzkern decompression not implemented')
     elif comp_type.startswith(b'zstd22'):
-        zstd = try_import('zstd')
-        return cast(bytes, zstd.uncompress(f.read(size)))
+        zstd = try_import('zstandard')
+        return cast(bytes, zstd.ZstdDecompressor().stream_reader(f.read(size)).read())
 
     raise NotImplementedError(f'unknown compressed type: {comp_type!r}')
 
@@ -226,8 +226,8 @@ def maybe_decompress(filename: Union[str, Path]) -> bytes:
         return cast(bytes, gzip.open(f).read())
 
     if start.startswith(b'\x28\xb5\x2f\xfd'):
-        zstd = try_import('zstd')
-        return cast(bytes, zstd.uncompress(f.read()))
+        zstd = try_import('zstandard')
+        return cast(bytes, zstd.ZstdDecompressor().stream_reader(f.read()).read())
 
     if start.startswith(b'\x02\x21\x4c\x18'):
         lz4 = try_import('lz4.frame', 'lz4')