OSError: [Errno 22] Invalid argument

[vectro]

Seeing this in CI:

.venv/lib/python3.9/site-packages/gitinfo/gitinfo.py:120: in get_git_info
    return get_git_info_dir(gitdir)
.venv/lib/python3.9/site-packages/gitinfo/gitinfo.py:98: in get_git_info_dir
    r = get_pack_info(idx_file, gi)
.venv/lib/python3.9/site-packages/gitinfo/pack_reader.py:176: in get_pack_info
    data = get_object(fin, pack_idx)
.venv/lib/python3.9/site-packages/gitinfo/pack_reader.py:149: in get_object
    data, r = decode_delta(fin, data, delta_res, pack_idx, offset)
.venv/lib/python3.9/site-packages/gitinfo/pack_reader.py:104: in decode_delta
    oo = get_object(fin, pack_idx - offset)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
fin = <_io.BufferedReader name='[redacted].pack'>
pack_idx = -14268
    def get_object(fin, pack_idx):
>       fin.seek(pack_idx, 0)
E       OSError: [Errno 22] Invalid argument

This started happening all of a sudden, presumably because git moved some needed object into a pack? Now it is happening consistently.

This is observed in a private repo using python-git-info 0.8.3 and Python 3.9.6.

[spapas]

Hello thank you for reporting this. It seems that for some reason the pack_idx is a negative number (I guess because it isn't read properly in the get_pack_idx function) thus fin.seek will error out...

Now what is really strange is that if you look at line 61 of pack_reader.py (where the pack_idx is read), you'll find pack_idx = struct.unpack("!I", fin.read(4))[0] which means that it should be read like an unsigned integer so there is no way a negative number is returned from there!

Unfortunately I cant reproduce it with the git repos I tried, if you have any idea for how to debug that I'll be happy to try it!

[iankjames]

FWIW, I observed the same behavior recently (v0.8.3, Python 3.11.4) – I was able to fix this by simply deleting the repo, then re-cloning it...my guess is the git configuration (in .git) got into some odd and/or stale state, but wasn't able to dig into exactly what happened and/or changed.

Hope this works for you, @vectro!

[zpeschke]

I'm running into this as well. Recloning does not fix it, unfortunately. The pack_idx is negative because a large offset is calculated and passed to decode_delta. Could there be an issue with the way the offset is calculated?

https://github.com/spapas/python-git-info/blob/master/gitinfo/pack_reader.py#L137-L149

$ git version
git version 2.34.1

get_object pack_idx: 228
get_object obj_len: 1547
get_object byte0: 128
get_object offset: 22528
decode_delta pack_idx: 228
decode_delta offset: 22528
get_object pack_idx: -22300
...
  File "/tmp/venv/lib/python3.11/site-packages/gitinfo/pack_reader.py", line 106, in decode_delta
    oo = get_object(fin, pack_idx - offset)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/venv/lib/python3.11/site-packages/gitinfo/pack_reader.py", line 127, in get_object
    fin.seek(pack_idx, 0)
OSError: [Errno 22] Invalid argument

[spapas]

@zpeschke is this on a public repo so I can debug it ?

[zpeschke]

@zpeschke is this on a public repo so I can debug it ?

Not a public repo, unfortunately. I'll see if I can recreate it within a public one.

[spapas]

@zpeschke thank you! Also I'd be happy to accept a PR that fixes your problem if you care to debug the problematic part.