`get_offset_reader_file_id` is incorrect in ledger.rs

[sujeet]

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Problem

Current impl:

    fn get_offset_reader_file_id(&self, offset: u16) -> u16 {
        self.get_current_reader_file_id().wrapping_add(offset) % MAX_FILE_ID
    }

Consider:

current = 65534, offset = 1, returns 0
65534.wrapping_add(1) % 65535
65535                 % 65535
0

current = 65534, offset = 2, still returns 0
65534.wrapping_add(2) % 65535
0                     % 65535
0

One way to fix:

    fn get_offset_reader_file_id(&self, offset: u16) -> u16 {
        let curr = u32::from(self.get_current_reader_file_id());
        let off = u32::from(offset);
        u16::try_from((curr + off) % u32::from(MAX_FILE_ID))
            .expect("(_ % MAX_FILE_ID) always fits in u16")
    }

This is also a likely root-cause of #19759

Configuration

Version

latest (v0.55.0)

Debug Output

Example Data

No response

Additional Context

No response

References

No response

[sujeet]

vector/lib/vector-buffers/src/variants/disk_v2/ledger.rs

Line 154 in f06f820

fn get_offset_reader_file_id(&self, offset: u16) -> u16 {