> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/caf-filling-sdp-structures.md).

# CAF: Filling SDP Structures

There are two ways to fill a TBX\_SDP\_INFO structure.

#### Filling a TBX\_SDP\_INFO structure from a text SDP:

```
TBX_RESULT CallBridgingSampleLoadConfig_DB
(
IN  PCALL_BRIDGING_SAMPLE_CONTEXT		in_pContext,
OUT PCALL_BRIDGING_SAMPLE_DYNAMIC_CONFIG	out_pDynamicConfig,
OUT TBX_CHAR				out_szResult[ TBCAF_DB_FULL_PATH_NAME_MAX ]
)
{
CTBCAFOam_sdp_profiles_db_acc       AccessSdpProfiles;
PITBCAFDb                           pCfgDb;
std::vector<CTBCAFOam_sdp_profiles> SdpProfiles;
CTBCAFOam_sdp_profiles              SdpProfile;
TBX_SDP_INFO                        SdpInfo;
CTBCAFString                        strSdpText;

pCfgDb = in_pContext->pCppCtx->pCfgDb;

Result = AccessSdpProfiles.Init(pCfgDb);
if (TBX_RESULT_FAILURE(Result))
{
TBX_EXIT_ERROR (Result, 0, "Cannot init AccessSdpProfiles" );
}

SdpProfiles = AccessSdpProfiles.GetAllBy_profile_id( 1 );
SdpProfile  = SdpProfiles[0];

'''strSdpText = SdpProfile.str_sdp_text;'''
'''if( !strSdpText.EndsWith( "\r\n" ) )'''
'''{'''
'''      strSdpText.Append( "\r\n" );'''
'''}'''

'''/* Fill media capabilities */'''
'''Result = TBXMediaLibSdpParse'''
'''('''
'''    (PTBX_CHAR)strSdpText.c_str(),'''
'''    &SdpInfo,'''
'''    TBX_MEDIA_SDP_PARSE_OPTION_DEFAULT'''
''');'''

'''// SdpInfo is now filled with the info from the text SDP'''
}
```

#### Filling a TBX\_SDP\_INFO structure manually:

```
TBX_RESULT CTBS2GWSimpleMediaCall::BuildSdpInfo
(
IN  PTBX_CHAR		in_pszIp,
IN  TBX_UINT32		in_un32Port,
OUT TBX_SDP_INFO&	out_SdpInfo
)
{
TBCAF_MUTEX_GET_SCOPE_BEGIN( &mMutex )
PTBX_MEDIA_CAPABILITY			pCap;
PTBX_SDP_MEDIA_CONNECTION		pConn;
PTBX_MEDIA_CAPABILITY_DESCRIPTION	pMediaDesc;
/*---------------------------------------------------------------------------------------------------------------------------
|  Code section
```

* \--------------------------------------------------------------------------------------------------------------------------\*/ CAFCODE( CTBS2GWSimpleMediaCall::BuildSdpInfo ) { memset(\&out\_SdpInfo, 0, sizeof(out\_SdpInfo));

  // Set capabilities pCap = &( out\_SdpInfo.Capabilities.aMediaCap\[ out\_SdpInfo.Capabilities.un8NbMediaCapabilities ] ); { /\* Reserve this capability in aMediaCap \*/ out\_SdpInfo.Capabilities.un8NbMediaCapabilities++;

  pCap->Encoding.MediaType = TBX\_MEDIA\_TYPE\_AUDIO\_PCMU; pCap->Direction = TBX\_MEDIA\_DIRECTION\_RX\_TX\_SAME; pCap->Transport.Type = TBX\_MEDIA\_TRANSPORT\_TYPE\_RTP; pCap->Transport.Rtp.PayloadType = TBX\_MEDIA\_PAYLOAD\_TYPE\_PCMU; pCap->Transport.Rtp.un16MaxAudioFramesPerPacket = 160; pCap->Transport.Rtp.un16PacketDurationMs = 20; } pCap = &( out\_SdpInfo.Capabilities.aMediaCap\[ out\_SdpInfo.Capabilities.un8NbMediaCapabilities ] ); { /\* Reserve this capability in aMediaCap \*/ out\_SdpInfo.Capabilities.un8NbMediaCapabilities++;

  pCap->Encoding.MediaType = TBX\_MEDIA\_TYPE\_AUDIO\_PCMA; pCap->Direction = TBX\_MEDIA\_DIRECTION\_RX\_TX\_SAME; pCap->Transport.Type = TBX\_MEDIA\_TRANSPORT\_TYPE\_RTP; pCap->Transport.Rtp.PayloadType = TBX\_MEDIA\_PAYLOAD\_TYPE\_PCMA; pCap->Transport.Rtp.un16MaxAudioFramesPerPacket = 160; pCap->Transport.Rtp.un16PacketDurationMs = 40; } out\_SdpInfo.Capabilities.un8NbCapabilityGroups = 1; out\_SdpInfo.Capabilities.aCapGroups\[0].un8NbSimultaneousCap = 1; pMediaDesc = &( out\_SdpInfo.Capabilities.aCapGroups\[0].aSimultaneousCap\[ 0 ] ); pMediaDesc->un8NbPorts = in\_un32Port ? 1 : 0; pMediaDesc->un16UdpPort = in\_un32Port; pMediaDesc->un8ConnectionIdx = 0; pMediaDesc->un8NbChoices = 2; pMediaDesc->aMediaCapChoices\[0] = 0; pMediaDesc->aMediaCapChoices\[1] = 1;

  // Set connection info pConn = \&out\_SdpInfo.aConnections\[out\_SdpInfo.un8NbConnections]; pConn->un32NumAddr = 0; /\* Not used, not multicast */ pConn->un16Ttl = 0; /* Not used, not multicast \*/ pConn->IPDescriptionType = (TBX\_UINT8)TBX\_SDP\_MEDIA\_IP\_DESCRIPTION\_TYPE\_IPV4\_ADDRESS; Strncpy ( pConn->szIp, in\_pszIp, sizeof( pConn->szIp ) ); out\_SdpInfo.un8NbConnections++;

  TBX\_EXIT\_SUCCESS( TBX\_RESULT\_OK ); }

  /\*--------------------------------------------------------------------------------------------------------------------------- | Exception handling section
* \--------------------------------------------------------------------------------------------------------------------------\*/ CAF\_EXCEPTION\_HANDLING

  /\*--------------------------------------------------------------------------------------------------------------------------- | Error handling section
* \--------------------------------------------------------------------------------------------------------------------------\*/ CAF\_ERROR\_HANDLING( CAF\_VERBOSE ) { }

  /\*--------------------------------------------------------------------------------------------------------------------------- | Cleanup section
* \--------------------------------------------------------------------------------------------------------------------------\*/ CAF\_CLEANUP { }

  RETURN; TBCAF\_MUTEX\_GET\_SCOPE\_END( \&mMutex ) }


---

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