Motivation:
The previous architecture had several issues:
- Duplicate DRB generation logic in generateDRB() and generateDRB_ASN1()
- Embedded SDAP/PDCP configs in drb_t created tight coupling
- No clear separation between RRC internal state and ASN.1 encoding
- Maintenance burden due to duplicated configuration logic
New Architecture:
- drb_t now only stores DRB-specific data (ID, PDU session ID, PDCP config)
- SDAP configuration moved to PDU session level (following PDCP design pattern)
- ASN.1 encoding helpers (nr_rrc_build_*_config_ie()) handle conversion
- Single source of truth for DRB creation in RRC via nr_rrc_add_drb()
Key changes:
- Store nr_sdap_configuration_t per PDU session
- Simplified drb_t structure: removed embedded SDAP/PDCP configs, added pdusession_id
- New helper: nr_rrc_build_sdap_config_ie()
- Updated createDRBlist() to use new helper functions and proper DRB ID lookup
- Refactored trigger_bearer_setup() to use nr_rrc_add_drb() and fill_e1_drb_to_setup()
- Removed generateDRB() and generateDRB_ASN1() functions
- Updated set_bearer_context_pdcp_config() to return config by value
- Added SDAP configuration header file for type definitions
This eliminates code duplication, improves maintainability, and creates
a cleaner separation between RRC state management and ASN.1 encoding.