fn key_may_match()

in common/rusty_leveldb_sgx/src/filter.rs [155:178]

• 21 lines of code
• 5 McCabe index (conditional complexity)

    fn key_may_match(&self, key: &[u8], filter: &[u8]) -> bool {
        if filter.len() == 0 {
            return true;
        }

        let bits = (filter.len() - 1) as u32 * 8;
        let k = filter[filter.len() - 1];
        let filter_adj = &filter[0..filter.len() - 1];

        if k > 30 {
            return true;
        }

        let mut h = self.bloom_hash(key);
        let delta = (h >> 17) | (h << 15);
        for _ in 0..k {
            let bitpos = (h % bits) as usize;
            if (filter_adj[bitpos / 8] & (1 << (bitpos % 8))) == 0 {
                return false;
            }
            h = (h as u64 + delta as u64) as u32;
        }
        true
    }