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Data Structures | Typedefs | Enumerations | Functions
sdp-utils.h File Reference

SDP utilities (headers) More...

#include <inttypes.h>
#include <glib.h>
#include "rtp.h"
#include "refcount.h"
Include dependency graph for sdp-utils.h:
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures

struct  janus_sdp
 Janus SDP internal object representation. More...
 
struct  janus_sdp_mline
 SDP m-line representation. More...
 
struct  janus_sdp_attribute
 SDP a= attribute representation. More...
 

Typedefs

typedef struct janus_sdp janus_sdp
 Janus SDP internal object representation.
 
typedef enum janus_sdp_mtype janus_sdp_mtype
 Helper enumeration to quickly identify m-line media types.
 
typedef enum janus_sdp_mdirection janus_sdp_mdirection
 Helper enumeration to quickly identify m-line directions.
 
typedef struct janus_sdp_mline janus_sdp_mline
 SDP m-line representation.
 
typedef struct janus_sdp_attribute janus_sdp_attribute
 SDP a= attribute representation.
 
typedef enum janus_sdp_oa_type janus_sdp_oa_type
 

Enumerations

enum  janus_sdp_mtype { JANUS_SDP_AUDIO , JANUS_SDP_VIDEO , JANUS_SDP_APPLICATION , JANUS_SDP_OTHER }
 Helper enumeration to quickly identify m-line media types. More...
 
enum  janus_sdp_mdirection {
  JANUS_SDP_DEFAULT , JANUS_SDP_SENDRECV , JANUS_SDP_SENDONLY , JANUS_SDP_RECVONLY ,
  JANUS_SDP_INACTIVE , JANUS_SDP_INVALID
}
 Helper enumeration to quickly identify m-line directions. More...
 
enum  janus_sdp_oa_type {
  JANUS_SDP_OA_MLINE = 1 , JANUS_SDP_OA_ENABLED , JANUS_SDP_OA_DIRECTION , JANUS_SDP_OA_MID ,
  JANUS_SDP_OA_MSID , JANUS_SDP_OA_CODEC , JANUS_SDP_OA_EXTENSION , JANUS_SDP_OA_EXTENSIONS ,
  JANUS_SDP_OA_ACCEPT_EXTMAP , JANUS_SDP_OA_PT , JANUS_SDP_OA_FMTP , JANUS_SDP_OA_AUDIO_DTMF ,
  JANUS_SDP_OA_OPUSRED_PT , JANUS_SDP_OA_ACCEPT_OPUSRED , JANUS_SDP_OA_VP9_PROFILE , JANUS_SDP_OA_H264_PROFILE ,
  JANUS_SDP_OA_VIDEO_RTCPFB_DEFAULTS , JANUS_SDP_OA_DATA_LEGACY , JANUS_SDP_OA_DONE = 0
}
 

Functions

janus_sdp_mtype janus_sdp_parse_mtype (const char *type)
 Helper method to get a janus_sdp_mtype from a string.
 
const char * janus_sdp_mtype_str (janus_sdp_mtype type)
 Helper method to get the string associated to a janus_sdp_mtype value.
 
janus_sdp_mdirection janus_sdp_parse_mdirection (const char *direction)
 Helper method to get a janus_sdp_mdirection from a string.
 
const char * janus_sdp_mdirection_str (janus_sdp_mdirection direction)
 Helper method to get the string associated to a janus_sdp_mdirection value.
 
void janus_sdp_find_preferred_codec (janus_sdp *sdp, janus_sdp_mtype type, int index, const char **codec)
 Helper method to return the preferred audio or video codec in an SDP offer or answer, (where by preferred we mean the codecs we prefer ourselves, and not the m-line SDP order) as long as the m-line direction is not disabled (port=0 or direction=inactive) in the SDP.
 
void janus_sdp_find_first_codec (janus_sdp *sdp, janus_sdp_mtype type, int index, const char **codec)
 Helper method to return the first audio or video codec in an SDP offer or answer, (no matter whether we personally prefer them ourselves or not) as long as the m-line direction is not disabled (port=0 or direction=inactive) in the SDP.
 
const char * janus_sdp_match_preferred_codec (janus_sdp_mtype type, char *codec)
 Helper method to match a codec to one of the preferred codecs.
 
janus_sdp_mlinejanus_sdp_mline_create (janus_sdp_mtype type, guint16 port, const char *proto, janus_sdp_mdirection direction)
 Helper method to quickly create a janus_sdp_mline instance.
 
void janus_sdp_mline_destroy (janus_sdp_mline *mline)
 Helper method to free a janus_sdp_mline instance.
 
janus_sdp_mlinejanus_sdp_mline_find (janus_sdp *sdp, janus_sdp_mtype type)
 Helper method to get the janus_sdp_mline associated to a media type.
 
janus_sdp_mlinejanus_sdp_mline_find_by_index (janus_sdp *sdp, int index)
 Helper method to get the janus_sdp_mline by its index.
 
int janus_sdp_mline_remove (janus_sdp *sdp, janus_sdp_mtype type)
 Helper method to remove the janus_sdp_mline associated to a media type from the SDP.
 
janus_sdp_attributejanus_sdp_attribute_create (const char *name, const char *value,...) G_GNUC_PRINTF(2
 Helper method to quickly create a janus_sdp_attribute instance.
 
janus_sdp_attribute void janus_sdp_attribute_destroy (janus_sdp_attribute *attr)
 Helper method to free a janus_sdp_attribute instance.
 
int janus_sdp_attribute_add_to_mline (janus_sdp_mline *mline, janus_sdp_attribute *attr)
 Helper method to add an attribute to a media line.
 
janus_sdpjanus_sdp_parse (const char *sdp, char *error, size_t errlen)
 Method to parse an SDP string to a janus_sdp object.
 
int janus_sdp_remove_payload_type (janus_sdp *sdp, int index, int pt)
 Helper method to quickly remove all traces (m-line, rtpmap, fmtp, etc.) of a payload type.
 
char * janus_sdp_write (janus_sdp *sdp)
 Method to serialize a janus_sdp object to an SDP string.
 
janus_sdpjanus_sdp_new (const char *name, const char *address)
 Method to quickly generate a janus_sdp instance from a few selected fields.
 
void janus_sdp_destroy (janus_sdp *sdp)
 Method to destroy a Janus SDP object.
 
const char * janus_sdp_oa_type_str (janus_sdp_oa_type type)
 
janus_sdpjanus_sdp_generate_offer (const char *name, const char *address,...)
 Method to generate a janus_sdp offer, using variable arguments to dictate what to negotiate (e.g., in terms of media to offer, directions, etc.). Variable arguments are in the form of a sequence of name-value terminated by a JANUS_SDP_OA_DONE, e.g.:
 
int janus_sdp_generate_offer_mline (janus_sdp *offer,...)
 Method to add a single m-line to a new offer, using the same variable arguments janus_sdp_generate_offer supports. This is useful whenever you need to create a new offer, but don't know in advance how many m-lines you'll need, or it would be hard to do programmatically in a single call to janus_sdp_generate_offer. The first argument MUST be JANUS_SDP_OA_MLINE, specifying the type of the media.
 
janus_sdpjanus_sdp_generate_answer (janus_sdp *offer)
 Method to generate a janus_sdp answer to a provided janus_sdp offer. Notice that this doesn't address the individual m-lines: it will just create an empty response, create the corresponding m-lines, but leave them all "rejected". To answer each m-line you'll have to iterate on the offer m-lines and call janus_sdp_generate_answer_mline instead, e.g.:
 
int janus_sdp_generate_answer_mline (janus_sdp *offer, janus_sdp *answer, janus_sdp_mline *offered,...)
 Method to respond to a single m-line in an offer, using the same variable arguments janus_sdp_generate_offer_mline supports. The first argument MUST be JANUS_SDP_OA_MLINE, specifying the type of the media, e.g.:
 
int janus_sdp_get_codec_pt (janus_sdp *sdp, int index, const char *codec)
 Helper to get the payload type associated to a specific codec in an m-line.
 
int janus_sdp_get_codec_pt_full (janus_sdp *sdp, int index, const char *codec, const char *profile)
 Helper to get the payload type associated to a specific codec, in an m-line, taking into account a codec profile as a hint as well.
 
const char * janus_sdp_get_codec_name (janus_sdp *sdp, int index, int pt)
 Helper to get the codec name associated to a specific payload type in an m-line.
 
const char * janus_sdp_get_rtpmap_codec (const char *rtpmap)
 Helper to get the codec name associated to a specific rtpmap.
 
const char * janus_sdp_get_codec_rtpmap (const char *codec)
 Helper to get the rtpmap associated to a specific codec.
 
const char * janus_sdp_get_fmtp (janus_sdp *sdp, int index, int pt)
 Helper to get the fmtp associated to a specific payload type.
 
char * janus_sdp_get_video_profile (janus_videocodec codec, const char *fmtp)
 Helper to extract the H.264 or VP9 profile from a fmtp string.
 
int janus_sdp_get_opusred_pt (janus_sdp *sdp, int index)
 Helper to get the opus/red payload type from an SDP, if present.
 

Detailed Description

SDP utilities (headers)

Author
Lorenzo Miniero loren.nosp@m.zo@m.nosp@m.eetec.nosp@m.ho.c.nosp@m.om

Implementation of an internal SDP representation. Allows to parse SDP strings to an internal janus_sdp object, the manipulation of such object by playing with its properties, and a serialization to an SDP string that can be passed around. Since they don't have any core dependencies, these utilities can be used by plugins as well.

Core

Typedef Documentation

◆ janus_sdp

typedef struct janus_sdp janus_sdp

Janus SDP internal object representation.

◆ janus_sdp_attribute

typedef struct janus_sdp_attribute janus_sdp_attribute

SDP a= attribute representation.

◆ janus_sdp_mdirection

Helper enumeration to quickly identify m-line directions.

◆ janus_sdp_mline

typedef struct janus_sdp_mline janus_sdp_mline

SDP m-line representation.

◆ janus_sdp_mtype

Helper enumeration to quickly identify m-line media types.

◆ janus_sdp_oa_type

Enumeration Type Documentation

◆ janus_sdp_mdirection

Helper enumeration to quickly identify m-line directions.

Enumerator
JANUS_SDP_DEFAULT 

default=sendrecv

JANUS_SDP_SENDRECV 

sendrecv

JANUS_SDP_SENDONLY 

sendonly

JANUS_SDP_RECVONLY 

recvonly

JANUS_SDP_INACTIVE 

inactive

JANUS_SDP_INVALID 

invalid direction (when parsing)

◆ janus_sdp_mtype

Helper enumeration to quickly identify m-line media types.

Enumerator
JANUS_SDP_AUDIO 

m=audio

JANUS_SDP_VIDEO 

m=video

JANUS_SDP_APPLICATION 

m=application

JANUS_SDP_OTHER 

m=whatever (we don't care, unsupported)

◆ janus_sdp_oa_type

Enumerator
JANUS_SDP_OA_MLINE 

Add a new m-line of the specific kind (used as a separator for audio, video and data details passed to janus_sdp_generate_offer)

JANUS_SDP_OA_ENABLED 

Whether we should enable a specific m-line when offering/answering (depends on what follows, true by default)

JANUS_SDP_OA_DIRECTION 

When generating an offer or answer automatically, use this direction for media (depends on value that follows, sendrecv by default)

JANUS_SDP_OA_MID 

When generating an offer automatically, use this mid (depends on value that follows, needs to be a string)

JANUS_SDP_OA_MSID 

When generating an offer or answer automatically, use this msid (depends on the two strings that follow, stream and track ID respectively)

JANUS_SDP_OA_CODEC 

When generating an offer or answer automatically, use this codec (depends on value that follows, opus/vp8 by default)

JANUS_SDP_OA_EXTENSION 

When generating an offer (this is ignored for answers), negotiate this extension: needs two arguments, extmap value and extension ID (can be used multiple times)

JANUS_SDP_OA_EXTENSIONS 

When generating an offer (this is ignored for answers), negotiate these extensions: needs a hashtable with the mappings to a specific extmap.

Note
This is only used internally, and will be ignored if provided; in plugins, you should stick to JANUS_SDP_OA_EXTENSION
JANUS_SDP_OA_ACCEPT_EXTMAP 

When generating an answer (this is ignored for offers), accept this extension (by default, we reject them all; can be used multiple times)

JANUS_SDP_OA_PT 

When generating an offer (this is ignored for answers), use this payload type (depends on value that follows)

JANUS_SDP_OA_FMTP 

When generating an offer or answer automatically, add this custom fmtp string.

Note
When dealing with video, this property is ignored if JANUS_SDP_OA_VP9_PROFILE or JANUS_SDP_OA_H264_PROFILE is used on a compliant codec.
JANUS_SDP_OA_AUDIO_DTMF 

When generating an offer or answer automatically, do or do not negotiate telephone events (FIXME telephone-event/8000 only, true by default)

JANUS_SDP_OA_OPUSRED_PT 

When generating an offer (this is ignored for answers), use this payload type for RED/Opus (depends on value that follows)

JANUS_SDP_OA_ACCEPT_OPUSRED 

When generating an answer (this is ignored for offers), accept opus/red if offered.

JANUS_SDP_OA_VP9_PROFILE 

When generating an offer or answer automatically, use this profile for VP9 (depends on value that follows)

JANUS_SDP_OA_H264_PROFILE 

When generating an offer or answer automatically, use this profile for H.264 (depends on value that follows)

JANUS_SDP_OA_VIDEO_RTCPFB_DEFAULTS 

When generating an offer or answer automatically, do or do not add the rtcpfb attributes we typically negotiate (fir, nack, pli, remb; true by default)

JANUS_SDP_OA_DATA_LEGACY 

When generating an offer (this is ignored for answers), use the old "DTLS/SCTP" instead of the new "UDP/DTLS/SCTP (depends on what follows, false by default)

JANUS_SDP_OA_DONE 

MUST be used as the last argument in janus_sdp_generate_offer, janus_sdp_generate_offer_mline and janus_sdp_generate_answer.

Function Documentation

◆ janus_sdp_attribute_add_to_mline()

int janus_sdp_attribute_add_to_mline ( janus_sdp_mline * mline,
janus_sdp_attribute * attr )

Helper method to add an attribute to a media line.

Parameters
[in]mlineThe m-line to add the attribute to
[in]attrThe attribute to add
Returns
0 in case of success, -1 otherwise

◆ janus_sdp_attribute_create()

janus_sdp_attribute * janus_sdp_attribute_create ( const char * name,
const char * value,
... )

Helper method to quickly create a janus_sdp_attribute instance.

Parameters
[in]nameName of the attribute
[in]valueValue of the attribute, as a printf compliant string (variable arguments)
Returns
A pointer to a valid janus_sdp_attribute instance, if successful, NULL otherwise

◆ janus_sdp_attribute_destroy()

janus_sdp_attribute void janus_sdp_attribute_destroy ( janus_sdp_attribute * attr)

Helper method to free a janus_sdp_attribute instance.

Note
This method does not remove the attribute from the global or m-line attributes, that's up to the caller
Parameters
[in]attrThe janus_sdp_attribute instance to free

◆ janus_sdp_destroy()

void janus_sdp_destroy ( janus_sdp * sdp)

Method to destroy a Janus SDP object.

Parameters
[in]sdpThe Janus SDP object to free

◆ janus_sdp_find_first_codec()

void janus_sdp_find_first_codec ( janus_sdp * sdp,
janus_sdp_mtype type,
int index,
const char ** codec )

Helper method to return the first audio or video codec in an SDP offer or answer, (no matter whether we personally prefer them ourselves or not) as long as the m-line direction is not disabled (port=0 or direction=inactive) in the SDP.

Note
The codec argument is input/output, and it will be set to a static value in janus_preferred_audio_codecs or janus_preferred_video_codecs, so don't free it.
Parameters
[in]sdpThe Janus SDP object to parse
[in]typeWhether we're looking at an audio or video codec
[in]indexThe m-line to refer to (use -1 for the first m-line that matches)
[out]codecThe audio or video codec that was found

◆ janus_sdp_find_preferred_codec()

void janus_sdp_find_preferred_codec ( janus_sdp * sdp,
janus_sdp_mtype type,
int index,
const char ** codec )

Helper method to return the preferred audio or video codec in an SDP offer or answer, (where by preferred we mean the codecs we prefer ourselves, and not the m-line SDP order) as long as the m-line direction is not disabled (port=0 or direction=inactive) in the SDP.

Note
The codec argument is input/output, and it will be set to a static value in janus_preferred_audio_codecs or janus_preferred_video_codecs, so don't free it.
Parameters
[in]sdpThe Janus SDP object to parse
[in]typeWhether we're looking at an audio or video codec
[in]indexThe m-line to refer to (use -1 for the first m-line that matches)
[out]codecThe audio or video codec that was found

◆ janus_sdp_generate_answer()

janus_sdp * janus_sdp_generate_answer ( janus_sdp * offer)

Method to generate a janus_sdp answer to a provided janus_sdp offer. Notice that this doesn't address the individual m-lines: it will just create an empty response, create the corresponding m-lines, but leave them all "rejected". To answer each m-line you'll have to iterate on the offer m-lines and call janus_sdp_generate_answer_mline instead, e.g.:

       janus_sdp *answer = janus_sdp_generate_answer(offer);
       GList *temp = offer->m_lines;
       while(temp) {
        janus_sdp_mline *m = (janus_sdp_mline *)temp->data;
        janus_sdp_generate_answer_mline(offer, answer, m,
                [..]
                JANUS_SDP_OA_DONE);
        temp = temp->next;
       }

to only accept the audio stream being offered, but as recvonly, use Opus and reject both video and datachannels. Refer to the property names in the header file for a complete list of how you can drive the answer. The default, if not specified, is to accept everything as sendrecv.

Parameters
[in]offerThe Janus SDP offer to respond to
Returns
A pointer to a janus_sdp object, if successful, NULL otherwise

◆ janus_sdp_generate_answer_mline()

int janus_sdp_generate_answer_mline ( janus_sdp * offer,
janus_sdp * answer,
janus_sdp_mline * offered,
... )

Method to respond to a single m-line in an offer, using the same variable arguments janus_sdp_generate_offer_mline supports. The first argument MUST be JANUS_SDP_OA_MLINE, specifying the type of the media, e.g.:

       janus_sdp_generate_answer_mline(offer, answer, offer_mline,
        JANUS_SDP_OA_MLINE, JANUS_SDP_AUDIO,
                JANUS_SDP_OA_CODEC, "opus",
                JANUS_SDP_OA_DIRECTION, JANUS_SDP_RECVONLY,
        JANUS_SDP_OA_DONE);

to respond to an offered m-line with recvonly audio and use Opus.

Parameters
[in]offerThe Janus SDP offer
[in]answerThe Janus SDP answer to add the new m-line to
[in]offeredThe Janus SDP m-line from the offer to respond to
Returns
0 if successful, a negative integer otherwise

◆ janus_sdp_generate_offer()

janus_sdp * janus_sdp_generate_offer ( const char * name,
const char * address,
... )

Method to generate a janus_sdp offer, using variable arguments to dictate what to negotiate (e.g., in terms of media to offer, directions, etc.). Variable arguments are in the form of a sequence of name-value terminated by a JANUS_SDP_OA_DONE, e.g.:

       janus_sdp *offer = janus_sdp_generate_offer("My session", "127.0.0.1",
        JANUS_SDP_OA_MLINE, JANUS_SDP_AUDIO,
                JANUS_SDP_OA_PT, 100,
                JANUS_SDP_OA_DIRECTION, JANUS_SDP_SENDONLY,
                JANUS_SDP_OA_CODEC, "opus",
        JANUS_SDP_OA_MLINE, JANUS_SDP_VIDEO,
                JANUS_SDP_OA_PT, 101,
                JANUS_SDP_OA_DIRECTION, JANUS_SDP_RECVONLY,
                JANUS_SDP_OA_CODEC, "vp8",

to offer a sendonly Opus audio stream being offered with 100 as payload type, and a recvonly VP8 video stream with 101 as payload type. Refer to the property names in the header file for a complete list of how you can drive the offer. Other media streams can be added, as long as you prefix/specify them with JANUS_SDP_OA_MLINE as done here. The default, if not specified, is to not offer anything, meaning it will be up to you to add m-lines subsequently.

Parameters
[in]nameThe session name (if NULL, a default value will be set)
[in]addressThe IP to set in o= and c= fields (if NULL, a default value will be set)
Returns
A pointer to a janus_sdp object, if successful, NULL otherwise

◆ janus_sdp_generate_offer_mline()

int janus_sdp_generate_offer_mline ( janus_sdp * offer,
... )

Method to add a single m-line to a new offer, using the same variable arguments janus_sdp_generate_offer supports. This is useful whenever you need to create a new offer, but don't know in advance how many m-lines you'll need, or it would be hard to do programmatically in a single call to janus_sdp_generate_offer. The first argument MUST be JANUS_SDP_OA_MLINE, specifying the type of the media.

Note
In case case you add audio and don't specify anything else, the default is to use Opus and payload type 111. For video, the default is VP8 and payload type 96. The default media direction is sendrecv.
Parameters
[in]offerThe Janus SDP offer to add the new m-line to
Returns
0 if successful, a negative integer otherwise

◆ janus_sdp_get_codec_name()

const char * janus_sdp_get_codec_name ( janus_sdp * sdp,
int index,
int pt )

Helper to get the codec name associated to a specific payload type in an m-line.

Parameters
sdpThe Janus SDP instance to process
indexThe m-line to refer to (use -1 for the first m-line that matches)
ptThe payload type to find
Returns
The codec name, if found, or NULL otherwise

◆ janus_sdp_get_codec_pt()

int janus_sdp_get_codec_pt ( janus_sdp * sdp,
int index,
const char * codec )

Helper to get the payload type associated to a specific codec in an m-line.

Note
This version doesn't involve profiles, which means that in case of multiple payload types associated to the same codec because of different profiles (e.g., VP9 and H.264), this will simply return the first payload type associated with it the codec itself.
Parameters
sdpThe Janus SDP instance to process
indexThe m-line to refer to (use -1 for the first m-line that matches)
codecThe codec to find, as a string
Returns
The payload type, if found, or -1 otherwise

◆ janus_sdp_get_codec_pt_full()

int janus_sdp_get_codec_pt_full ( janus_sdp * sdp,
int index,
const char * codec,
const char * profile )

Helper to get the payload type associated to a specific codec, in an m-line, taking into account a codec profile as a hint as well.

Note
The profile will only be used if the codec supports it, and the core is aware of it: right now, this is only VP9 and H.264. If the codec is there but the profile is not found, then no payload type is returned.
Parameters
sdpThe Janus SDP instance to process
indexThe m-line to refer to (use -1 for the first m-line that matches)
codecThe codec to find, as a string
profileThe codec profile to use as a hint, as a string
Returns
The payload type, if found, or -1 otherwise

◆ janus_sdp_get_codec_rtpmap()

const char * janus_sdp_get_codec_rtpmap ( const char * codec)

Helper to get the rtpmap associated to a specific codec.

Parameters
codecThe codec name, as a string (e.g., "opus")
Returns
The rtpmap value, if found (e.g., "opus/48000/2"), or NULL otherwise

◆ janus_sdp_get_fmtp()

const char * janus_sdp_get_fmtp ( janus_sdp * sdp,
int index,
int pt )

Helper to get the fmtp associated to a specific payload type.

Parameters
sdpThe Janus SDP instance to process
indexThe m-line to refer to (use -1 for the first m-line that matches)
ptThe payload type to find
Returns
The fmtp content, if found, or NULL otherwise

◆ janus_sdp_get_opusred_pt()

int janus_sdp_get_opusred_pt ( janus_sdp * sdp,
int index )

Helper to get the opus/red payload type from an SDP, if present.

Parameters
sdpThe Janus SDP instance to process
indexThe m-line to refer to (use -1 for the first m-line that matches)
Returns
The payload type, if found, or -1 otherwise

◆ janus_sdp_get_rtpmap_codec()

const char * janus_sdp_get_rtpmap_codec ( const char * rtpmap)

Helper to get the codec name associated to a specific rtpmap.

Parameters
rtpmapThe rtpmap, as a string (e.g., "VP8/90000")
Returns
The codec name, if found (e.g., "vp8"), or NULL otherwise

◆ janus_sdp_get_video_profile()

char * janus_sdp_get_video_profile ( janus_videocodec codec,
const char * fmtp )

Helper to extract the H.264 or VP9 profile from a fmtp string.

Note
The returned profile string is allocated, so must be freed by the caller
Parameters
codecThe video codec to refer to
fmtpThe fmtp value to parse
Returns
The profile content, if found, or NULL otherwise

◆ janus_sdp_match_preferred_codec()

const char * janus_sdp_match_preferred_codec ( janus_sdp_mtype type,
char * codec )

Helper method to match a codec to one of the preferred codecs.

Note
Don't free the returned value, as it's a constant value
Parameters
[in]typeThe type of media to match
[in]codecThe codec to match
Returns
The codec, if found, or NULL otherwise

◆ janus_sdp_mdirection_str()

const char * janus_sdp_mdirection_str ( janus_sdp_mdirection direction)

Helper method to get the string associated to a janus_sdp_mdirection value.

Parameters
[in]directionThe direction to stringify
Returns
The direction as a string, if valid, or NULL otherwise

◆ janus_sdp_mline_create()

janus_sdp_mline * janus_sdp_mline_create ( janus_sdp_mtype type,
guint16 port,
const char * proto,
janus_sdp_mdirection direction )

Helper method to quickly create a janus_sdp_mline instance.

Note
The type_str property of the new m-line is created automatically depending on the provided type attribute. If type is JANUS_SDP_OTHER, though, type_str will NOT we allocated, and will be up to the caller.
Parameters
[in]typeType of the media (audio/video/application) as a janus_sdp_mtype
[in]portPort to advertise
[in]protoProfile to advertise
[in]directionDirection of the media as a janus_sdp_direction
Returns
A pointer to a valid janus_sdp_mline instance, if successful, NULL otherwise

◆ janus_sdp_mline_destroy()

void janus_sdp_mline_destroy ( janus_sdp_mline * mline)

Helper method to free a janus_sdp_mline instance.

Note
This method does not remove the m-line from the janus_sdp instance, that's up to the caller
Parameters
[in]mlineThe janus_sdp_mline instance to free

◆ janus_sdp_mline_find()

janus_sdp_mline * janus_sdp_mline_find ( janus_sdp * sdp,
janus_sdp_mtype type )

Helper method to get the janus_sdp_mline associated to a media type.

Note
This currently returns the first m-line of the specified type it finds: as such, it's mostly here for making things easier for plugins not doing multistream.
Parameters
[in]sdpThe Janus SDP object to search
[in]typeThe type of media to search
Returns
The janus_sdp_mline instance, if found, or NULL otherwise

◆ janus_sdp_mline_find_by_index()

janus_sdp_mline * janus_sdp_mline_find_by_index ( janus_sdp * sdp,
int index )

Helper method to get the janus_sdp_mline by its index.

Parameters
[in]sdpThe Janus SDP object to search
[in]indexThe index of the m-line in the SDP
Returns
The janus_sdp_mline instance, if found, or NULL otherwise

◆ janus_sdp_mline_remove()

int janus_sdp_mline_remove ( janus_sdp * sdp,
janus_sdp_mtype type )

Helper method to remove the janus_sdp_mline associated to a media type from the SDP.

Note
This currently removes the first m-line of the specified type it finds: as such, it's mostly here for making things easier for plugins not doing multistream.
Parameters
[in]sdpThe Janus SDP object to modify
[in]typeThe type of media to remove
Returns
0 if successful, a negative integer otherwise

◆ janus_sdp_mtype_str()

const char * janus_sdp_mtype_str ( janus_sdp_mtype type)

Helper method to get the string associated to a janus_sdp_mtype value.

Parameters
[in]typeThe type to stringify
Returns
The type as a string, if valid, or NULL otherwise

◆ janus_sdp_new()

janus_sdp * janus_sdp_new ( const char * name,
const char * address )

Method to quickly generate a janus_sdp instance from a few selected fields.

Note
This allocates the o_addr, s_name and c_addr properties: if you want to replace them, don't forget to g_free the original pointers first.
Parameters
[in]nameThe session name (if NULL, a default value will be set)
[in]addressThe IP to set in o= and c= fields (if NULL, a default value will be set)
Returns
A pointer to a janus_sdp object, if successful, NULL otherwise

◆ janus_sdp_oa_type_str()

const char * janus_sdp_oa_type_str ( janus_sdp_oa_type type)

◆ janus_sdp_parse()

janus_sdp * janus_sdp_parse ( const char * sdp,
char * error,
size_t errlen )

Method to parse an SDP string to a janus_sdp object.

Parameters
[in]sdpThe SDP string to parse
[in,out]errorBuffer to receive a reason for an error, if any
[in]errlenThe length of the error buffer
Returns
A pointer to a janus_sdp object, if successful, NULL otherwise; in case of errors, if provided the error string is filled with a reason

◆ janus_sdp_parse_mdirection()

janus_sdp_mdirection janus_sdp_parse_mdirection ( const char * direction)

Helper method to get a janus_sdp_mdirection from a string.

Parameters
[in]directionThe direction to parse as a string (e.g., "sendrecv")
Returns
The corresponding janus_sdp_mdirection value

◆ janus_sdp_parse_mtype()

janus_sdp_mtype janus_sdp_parse_mtype ( const char * type)

Helper method to get a janus_sdp_mtype from a string.

Parameters
[in]typeThe type to parse as a string (e.g., "audio")
Returns
The corresponding janus_sdp_mtype value

◆ janus_sdp_remove_payload_type()

int janus_sdp_remove_payload_type ( janus_sdp * sdp,
int index,
int pt )

Helper method to quickly remove all traces (m-line, rtpmap, fmtp, etc.) of a payload type.

Parameters
[in]sdpThe janus_sdp object to remove the payload type from
[in]indexThe m-line to remove the payload type from (use -1 for the first m-line that matches)
[in]ptThe payload type to remove
Returns
0 in case of success, a negative integer otherwise

◆ janus_sdp_write()

char * janus_sdp_write ( janus_sdp * sdp)

Method to serialize a janus_sdp object to an SDP string.

Parameters
[in]sdpThe janus_sdp object to serialize
Returns
A pointer to a string with the serialized SDP, if successful, NULL otherwise