fn get_index_and_data_at()

in below/store/src/cursor.rs [447:474]

• 27 lines of code
• 6 McCabe index (conditional complexity)

    fn get_index_and_data_at(&self, index_offset: usize) -> Result<(&IndexEntry, &[u8])> {
        let index_entry = self
            .get_index_entry_at(index_offset)
            .ok_or_else(|| anyhow!("Failed to get index entry at offset {}", index_offset))?;
        let data_mmap = self
            .data_mmap
            .as_ref()
            .ok_or_else(|| anyhow!("Failed to get mmap"))?;
        let data_offset = index_entry.offset as usize;
        let data_len = index_entry.len as usize;
        let data_slice = data_mmap
            .get(
                data_offset
                    ..(data_offset
                        .checked_add(data_len)
                        .ok_or_else(|| anyhow!("overflow"))?),
            )
            .ok_or_else(|| anyhow!("Failed to get data slice from mmap"))?;

        if data_slice.crc32() != index_entry.data_crc {
            bail!(
                "Corrupted data entry found: ts={} offset={:#x}",
                index_entry.timestamp,
                index_entry.offset,
            );
        };
        Ok((index_entry, data_slice))
    }