tree 819d867942b4fa6dc31d31085df57b21c752c498
parent 16b637bf1be08b88b1b74b42d4ea2a9c8982b665
author Neels Hofmeyr <neels@hofmeyr.de> 1565297298 +0200
committer Neels Hofmeyr <neels@hofmeyr.de> 1566944260 +0200

ptmap: implicitly match  '/8000' and '/8000/1'

In codecs_same(), do not compare the complete audio_name. The parts of it are
already checked individually:
- subtype_name ("AMR"),
- rate ("8000"; defaults to 8000 if omitted) and
- channels ("1"; defaults to 1 if omitted)
So by also checking the complete audio_name, we brushed over the match of
implicit "/8000" and "/8000/1", which otherwise works out fine.

As a result, translating payload type numbers in RTP headers now also works if
one conn of an endpoint set an rtpmap with "AMR/8000" and the other conn set
"AMR/8000/1".

It seems to me that most PBX out there generate ptmaps omitting the "/1", so
fixing this should make us more interoperable with third party SDP.

See IETF RFC4566 section 6. SDP Attributes:
  For audio streams, <encoding parameters> indicates the number
  of audio channels.  This parameter is OPTIONAL and may be
  omitted if the number of channels is one, provided that no
  additional parameters are needed.

Also allowing to omit the "/8000" is a mere side effect of this patch.
Omitting the rate does not seem to be specified in an RFC, but is logical for
audio codecs defined to require exactly 8000 set as rate (most GSM codecs).

Add tests in mgcp_test.c.

Change-Id: Iab00bf9a55b1847f85999077114b37e70fb677c2