Question regarding Reassembly and Fragmentation

[zyl-one]

Question

I am trying to parse TLS packets for SNI (Server Name Indication) over TCP. Most of the packets I see in Wireshark show that they are reassembled. (I'm not sure if this is TCP reassembly or IP fragmentation, as I have only recently started exploring these topics).

I am trying to understand how TCP reassembly and IP fragmentation work in PcapPlusPlus.

Should I handle IP fragmentation first and then pass the stream of data for TCP reassembly?
Is there a way to parse TCP packets directly after TCP reassembly in PcapPlusPlus (i.e., parse immediately if there are no segments, or reassemble and parse if there are segments, just like Wireshark)?

Operating systems

Windows, Linux (v23.09)