Reintroduce separate message types to simplify the encoding/decoding,
including shorter names. The old types will be removed once everything
has been migrated to the new encoder/decoder, which should ensure that
everything is properly migrated to the unit-tested encoder/decoders.
Also, for each type of F1 message (F1 UE context setup request,
response, modification request, ...) introduce a separate type to avoid
to mistakenly use wrong fields, which can lead to bugs. In this regard,
the DL PDCP SN bit size in the DRB-ToBeSetup list of the UE context
setup request is optional, as it will also be used in the UE context
modification request DRB SetupMod list (which avoids quite some code
duplication). The encoder checks that this IE is present, though.
Add a new target f1ap_lib that groups F1AP ASN.1 encoding&decoding for
messages defined f1ap_messages_types.h. The objective is to, for each
F1AP message,
- add encoder&decoder (similar to what already exists, but without
mandatory message sending afterwards)
- eq_X() function that checks two messages for equality (to be used
mostly in tests)
- cp_X() function that deep-copies a message, e.g., to be used when
sending ITTI messages, instead of manual copying done currently
- free_X() function that frees the memory associated to a memory, to
avoid memory leaks.
Each message will be tested, notably that encoding&decoding as well as
copying yield identical messages.
The actual message encoding & decoding, tests, and their use will be
done in the forthcoming commits.