Function unpack_objects 

pub fn unpack_objects(
    reader: &mut dyn Read,
    odb: &Odb,
    opts: &UnpackOptions,
) -> Result<usize>

Unpack a pack stream from reader into odb.

Reads the complete pack from reader, validates the trailing SHA-1 checksum, unpacks all objects (including full delta-chain resolution), and — unless UnpackOptions::dry_run is set — writes each object to odb.

Returns the total number of objects processed.

Errors

• Error::CorruptObject — invalid pack format, checksum mismatch, or unresolvable delta chains.
• Error::Io — I/O failure reading from reader.
• Error::Zlib — decompression failure.