Return status code instead of bool in IComposer

[gavv]

Summary

packet::IComposer is interface for protocol-specific serializators. See documentation.

Currently its methods return bool (true on success or false on error). We need to replace bool with status::StatusCode and return code that described why the operation failed.

Implementation

• Update IComposer interface and implementations:
  • rtp::Composer
  • fec::Composer
  • rtcp::Composer
• Report appropriate statuses:
  • when allocation failed, return StatusNoMem
  • when buffer is too small, return StatusBadBuffer
  • on success, return StatusOK
• Update users of composers. They should forward status to upper level:
  • fec::BlockWriter
  • packet::Shipper
  • audio::Packetizer
  • rtcp::Communicator

Testing

• Add unit tests for rtp::Composer and fec::Parser that check returned statuses in case of errors.
• Add unit tests for components which use composers, and check that they forward statuses from composer to the upper level (e.g. if Composer fails with StatusNoMem, Shipper::write() returns StatusNoMem). One test per component should be enough.

[ronazf]

Hi @gavv, I'd be happy to help with this issue.

[gavv]

@ronazf Thanks, welcome!