Method find_block_in_inode

atomic-core/src/pristine/txn/read.rs:1590–1648

(
        &self,
        inode: Inode,
        pos: Position<NodeId>,
    )

    }

    fn find_block_in_inode(
        &self,
        inode: Inode,
        pos: Position<NodeId>,
    ) -> Result<Option<GraphNode<NodeId>>, Self::InodeError> {
        let table = &self.inode_graph_table;
        let inode_id = inode.get();
        let change_id = pos.change.get();
        let target_pos = pos.pos.get();

        // Fast path: probe exact start position
        let exact_start = encode_inode_vertex(inode_id, change_id, target_pos, 0);
        let exact_end = encode_inode_vertex(inode_id, change_id, target_pos, u64::MAX);
        let mut empty_match = None;

        for result in table.range::<&[u8; 32]>(&exact_start..=&exact_end)? {
            let (key, _) = result?;
            let (_, v_change, v_start, v_end) = decode_inode_vertex(key.value());
            if v_change != change_id || v_start != target_pos {
                continue;
            }
            if v_start != v_end {
                return Ok(Some(GraphNode {
                    change: NodeId::new(v_change),
                    start: ChangePosition::new(v_start),
                    end: ChangePosition::new(v_end),
                }));
            }
            if empty_match.is_none() {
                empty_match = Some(GraphNode {
                    change: NodeId::new(v_change),
                    start: ChangePosition::new(v_start),
                    end: ChangePosition::new(v_end),
                });
            }
        }

        if let Some(m) = empty_match {
            return Ok(Some(m));
        }

        // Slow path: scan all vertices for this change within the inode
        let start_key = encode_inode_vertex(inode_id, change_id, 0, 0);
        let end_key = encode_inode_vertex(inode_id, change_id, u64::MAX, u64::MAX);

        for result in table.range::<&[u8; 32]>(&start_key..=&end_key)? {
            let (key, _) = result?;
            let (_, v_change, v_start, v_end) = decode_inode_vertex(key.value());
            if v_change == change_id && v_start <= target_pos && target_pos < v_end {
                return Ok(Some(GraphNode {
                    change: NodeId::new(v_change),
                    start: ChangePosition::new(v_start),
                    end: ChangePosition::new(v_end),
                }));
            }
        }

        Ok(None)