[sr-dev] adding ice attributes to sdp parser

[Juha Heinanen]

Ovidiu Sas writes:

> I think it would make sense to create a list of ice attributes so we
> can add the new attribute to the proper location.  Just like we add
> sdp_payload_attr to each stream we should add ice attributes to each
> stream.

ovidiu,

i agree, but that would be huge overhead on top of what i need to add
the relay candidate lines.

> This will make the retrieval of each attribute fast and adding a new
> ice attribute in proper place will be easier (as we would have proper
> pointers to where to insert the lumps).

i'm not sure about the proper place.  it looks to me that start of
the a lines is not currently stored anywhere, because the prefixes,
e.g., a=rtpmap:, are omitted.

> The ice attributes management should be very similar to
> sdp_payload_attr management.
> 
> typedef struct sdp_ice_attr {
>     struct sdp_ice_attr *next;
>     str foundation;
>     str component_id;
>     str transport;
>     str connection_addr
>     str port;
>     str candidate_type;
>     int candidateType; /* ICE_HOST/ICE_SRFLX/ICE_PRFLX/ICE_RELAY/ICE_UNKNOWN */
> } sdp_ice_attr_t;
> 
> and inside the sdp_stream_cell we add:
>     int ice_attrs_num; /**< number of ICE attrs inside a stream */
>     struct sdp_ice_attr **p_sdp_ice_attr; /**< fast access pointers to
> ice attrs */
>     struct sdp_ice_attr *ice_attr;
>
> Let me know what do you think?

what you suggest is what i thought too, but as i mentioned, it means
lots of extra work over what i currently need.  parsing of candidate
lines is all but a trivial thing to do.

how about if i do what you suggest, but don't fill in anything else in
struct sdp_ice_attr except foundation and component_id?  if someone
later needs the other field values, they can then add parsing of more
fields.

regarding the pointer to the start of a=candidate line, it would be
foundation.s - 12, right?

-- juha