## gstsdpmessage gstsdpmessage — Helper methods for dealing with SDP messages |

## Synopsis

    #include <gst/sdp/gstsdpmessage.h>

    enum                GstSDPResult;
                        GstSDPOrigin;
                        GstSDPConnection;
    #define             GST_SDP_BWTYPE_CT
    #define             GST_SDP_BWTYPE_AS
    #define             GST_SDP_BWTYPE_EXT_PREFIX
                        GstSDPBandwidth;
                        GstSDPTime;
                        GstSDPZone;
                        GstSDPKey;
                        GstSDPAttribute;
                        GstSDPMedia;
                        GstSDPMessage;
    GstSDPResult        gst_sdp_message_new                 (GstSDPMessage **msg);
    GstSDPResult        gst_sdp_message_init                (GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_uninit              (GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_free                (GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_parse_buffer        (const guint8 *data,
                                                             guint size,
                                                             GstSDPMessage *msg);
    const gchar*        gst_sdp_message_get_version         (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_version         (GstSDPMessage *msg,
                                                             const gchar *version);
    const GstSDPOrigin* gst_sdp_message_get_origin          (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_origin          (GstSDPMessage *msg,
                                                             const gchar *username,
                                                             const gchar *sess_id,
                                                             const gchar *sess_version,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *addr);
    const gchar*        gst_sdp_message_get_session_name    (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_session_name    (GstSDPMessage *msg,
                                                             const gchar *session_name);
    const gchar*        gst_sdp_message_get_information     (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_information     (GstSDPMessage *msg,
                                                             const gchar *information);
    const gchar*        gst_sdp_message_get_uri             (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_uri             (GstSDPMessage *msg,
                                                             const gchar *uri);
    guint               gst_sdp_message_emails_len          (const GstSDPMessage *msg);
    const gchar*        gst_sdp_message_get_email           (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_email           (GstSDPMessage *msg,
                                                             const gchar *email);
    guint               gst_sdp_message_phones_len          (const GstSDPMessage *msg);
    const gchar*        gst_sdp_message_get_phone           (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_phone           (GstSDPMessage *msg,
                                                             const gchar *phone);
    const GstSDPConnection* gst_sdp_message_get_connection  (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_connection      (GstSDPMessage *msg,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *address,
                                                             guint ttl,
                                                             guint addr_number);
    guint               gst_sdp_message_bandwidths_len      (const GstSDPMessage *msg);
    const GstSDPBandwidth* gst_sdp_message_get_bandwidth    (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_bandwidth       (GstSDPMessage *msg,
                                                             const gchar *bwtype,
                                                             guint bandwidth);
    guint               gst_sdp_message_times_len           (const GstSDPMessage *msg);
    const GstSDPTime*   gst_sdp_message_get_time            (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_time            (GstSDPMessage *msg,
                                                             const gchar *start,
                                                             const gchar *stop,
                                                             const gchar **repeat);
    guint               gst_sdp_message_zones_len           (const GstSDPMessage *msg);
    const GstSDPZone*   gst_sdp_message_get_zone            (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_zone            (GstSDPMessage *msg,
                                                             const gchar *adj_time,
                                                             const gchar *typed_time);
    const GstSDPKey*    gst_sdp_message_get_key             (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_message_set_key             (GstSDPMessage *msg,
                                                             const gchar *type,
                                                             const gchar *data);
    guint               gst_sdp_message_attributes_len      (const GstSDPMessage *msg);
    const GstSDPAttribute* gst_sdp_message_get_attribute    (const GstSDPMessage *msg,
                                                             guint idx);
    const gchar*        gst_sdp_message_get_attribute_val   (const GstSDPMessage *msg,
                                                             const gchar *key);
    const gchar*        gst_sdp_message_get_attribute_val_n (const GstSDPMessage *msg,
                                                             const gchar *key,
                                                             guint nth);
    GstSDPResult        gst_sdp_message_add_attribute       (GstSDPMessage *msg,
                                                             const gchar *key,
                                                             const gchar *value);
    guint               gst_sdp_message_medias_len          (const GstSDPMessage *msg);
    const GstSDPMedia*  gst_sdp_message_get_media           (const GstSDPMessage *msg,
                                                             guint idx);
    GstSDPResult        gst_sdp_message_add_media           (GstSDPMessage *msg,
                                                             GstSDPMedia *media);
    GstSDPResult        gst_sdp_message_dump                (const GstSDPMessage *msg);
    GstSDPResult        gst_sdp_media_new                   (GstSDPMedia **media);
    GstSDPResult        gst_sdp_media_init                  (GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_uninit                (GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_free                  (GstSDPMedia *media);
    const gchar*        gst_sdp_media_get_media             (const GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_set_media             (GstSDPMedia *media,
                                                             const gchar *med);
    guint               gst_sdp_media_get_port              (const GstSDPMedia *media);
    guint               gst_sdp_media_get_num_ports         (const GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_set_port_info         (GstSDPMedia *media,
                                                             guint port,
                                                             guint num_ports);
    const gchar*        gst_sdp_media_get_proto             (const GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_set_proto             (GstSDPMedia *media,
                                                             const gchar *proto);
    guint               gst_sdp_media_formats_len           (const GstSDPMedia *media);
    const gchar*        gst_sdp_media_get_format            (const GstSDPMedia *media,
                                                             guint idx);
    GstSDPResult        gst_sdp_media_add_format            (GstSDPMedia *media,
                                                             const gchar *format);
    const gchar*        gst_sdp_media_get_information       (const GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_set_information       (GstSDPMedia *media,
                                                             const gchar *information);
    guint               gst_sdp_media_connections_len       (const GstSDPMedia *media);
    const GstSDPConnection* gst_sdp_media_get_connection    (const GstSDPMedia *media,
                                                             guint idx);
    GstSDPResult        gst_sdp_media_add_connection        (GstSDPMedia *media,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *address,
                                                             guint ttl,
                                                             guint addr_number);
    guint               gst_sdp_media_bandwidths_len        (const GstSDPMedia *media);
    const GstSDPBandwidth* gst_sdp_media_get_bandwidth      (const GstSDPMedia *media,
                                                             guint idx);
    GstSDPResult        gst_sdp_media_add_bandwidth         (GstSDPMedia *media,
                                                             const gchar *bwtype,
                                                             guint bandwidth);
    const GstSDPKey*    gst_sdp_media_get_key               (const GstSDPMedia *media);
    GstSDPResult        gst_sdp_media_set_key               (GstSDPMedia *media,
                                                             const gchar *type,
                                                             const gchar *data);
    guint               gst_sdp_media_attributes_len        (const GstSDPMedia *media);
    const GstSDPAttribute* gst_sdp_media_get_attribute      (const GstSDPMedia *media,
                                                             guint idx);
    const gchar*        gst_sdp_media_get_attribute_val     (const GstSDPMedia *media,
                                                             const gchar *key);
    const gchar*        gst_sdp_media_get_attribute_val_n   (const GstSDPMedia *media,
                                                             const gchar *key,
                                                             guint nth);
    GstSDPResult        gst_sdp_media_add_attribute         (GstSDPMedia *media,
                                                             const gchar *key,
                                                             const gchar *value);

## Description

The GstSDPMessage helper functions makes it easy to parse and create SDP messages.

Last reviewed on 2007-07-24 (0.10.14)

## Details

### enum GstSDPResult

    typedef enum {
      GST_SDP_OK     = 0,
      GST_SDP_EINVAL = -1
    } GstSDPResult;

Return values for the SDP functions.

`GST_SDP_OK` | A successful return value
`GST_SDP_EINVAL` | a function was given invalid parameters

### GstSDPOrigin

    typedef struct {
      gchar *username;
      gchar *sess_id;
      gchar *sess_version;
      gchar *nettype;
      gchar *addrtype;
      gchar *addr;
    } GstSDPOrigin;

The contents of the SDP "o=" field which gives the originator of the session (their username and the address of the user's host) plus a session id and session version number.

gchar *`username`; | the user's login on the originating host, or it is "-" if the originating host does not support the concept of user ids.
gchar *`sess_id`; | is a numeric string such that the tuple of `username`, `sess_id`, `nettype`, `addrtype` and `addr` form a globally unique identifier for the session.
gchar *`sess_version`; | a version number for this announcement
gchar *`nettype`; | the type of network. "IN" is defined to have the meaning "Internet".
gchar *`addrtype`; | the type of `addr`.
gchar *`addr`; | the globally unique address of the machine from which the session was created.

### GstSDPConnection

    typedef struct {
      gchar *nettype;
      gchar *addrtype;
      gchar *address;
      guint  ttl;
      guint  addr_number;
    } GstSDPConnection;

The contents of the SDP "c=" field which contains connection data.

gchar *`nettype`; | the type of network. "IN" is defined to have the meaning "Internet".
gchar *`addrtype`; | the type of `address`.
gchar *`address`; | the address
guint `ttl`; | the time to live of the address
guint `addr_number`; | the number of layers

### GST_SDP_BWTYPE_CT

    #define GST_SDP_BWTYPE_CT 		"CT"

The Conference Total bandwidth modifier.

### GST_SDP_BWTYPE_AS

    #define GST_SDP_BWTYPE_AS 		"AS"

The Application-Specific Maximum bandwidth modifier.

### GST_SDP_BWTYPE_EXT_PREFIX

    #define GST_SDP_BWTYPE_EXT_PREFIX 	"X-"

The extension prefix bandwidth modifier.

### GstSDPBandwidth

    typedef struct {
      gchar *bwtype;
      guint  bandwidth;
    } GstSDPBandwidth;

The contents of the SDP "b=" field which specifies the proposed bandwidth to be used by the session or media.

gchar *`bwtype`; | the bandwidth modifier type
guint `bandwidth`; | the bandwidth in kilobits per second

### GstSDPTime

    typedef struct {
      gchar  *start;
      gchar  *stop;
      GArray *repeat;
    } GstSDPTime;

The contents of the SDP "t=" field which specify the start and stop times for a conference session.

gchar *`start`; | start time for the conference. The value is the decimal representation of Network Time Protocol (NTP) time values in seconds
gchar *`stop`; | stop time for the conference. The value is the decimal representation of Network Time Protocol (NTP) time values in seconds
GArray *`repeat`; | repeat times for a session

### GstSDPZone

    typedef struct {
      gchar *time;
      gchar *typed_time;
    } GstSDPZone;

The contents of the SDP "z=" field which allows the sender to specify a list of time zone adjustments and offsets from the base time.

gchar *`time`; | the NTP time that a time zone adjustment happens
gchar *`typed_time`; | the offset from the time when the session was first scheduled

### GstSDPKey

    typedef struct {
      gchar *type;
      gchar *data;
    } GstSDPKey;

The contents of the SDP "k=" field which is used to convey encryption keys.

gchar *`type`; | the encryption type
gchar *`data`; | the encryption data

### GstSDPAttribute

    typedef struct {
      gchar *key;
      gchar *value;
    } GstSDPAttribute;

The contents of the SDP "a=" field which contains a key/value pair.

gchar *`key`; | the attribute key
gchar *`value`; | the attribute value or NULL when it was a property attribute

### GstSDPMedia

    typedef struct {
      gchar            *media;
      guint             port;
      guint             num_ports;
      gchar            *proto;
      GArray           *fmts;
      gchar            *information;
      GArray           *connections;
      GArray           *bandwidths;
      GstSDPKey         key;
      GArray           *attributes;
    } GstSDPMedia;

The contents of the SDP "m=" field with all related fields.

gchar *`media`; | the media type
guint `port`; | the transport port to which the media stream will be sent
guint `num_ports`; | the number of ports or -1 if only one port was specified
gchar *`proto`; | the transport protocol
GArray *`fmts`; | an array of gchar formats
gchar *`information`; | the media title
GArray *`connections`; | array of GstSDPConnection with media connection information
GArray *`bandwidths`; | array of GstSDPBandwidth with media bandwidth information
GstSDPKey `key`; | the encryption key
GArray *`attributes`; | array of GstSDPAttribute with the additional media attributes

### GstSDPMessage

    typedef struct {
      gchar            *version;
      GstSDPOrigin      origin;
      gchar            *session_name;
      gchar            *information;
      gchar            *uri;
      GArray           *emails;
      GArray           *phones;
      GstSDPConnection  connection;
      GArray           *bandwidths;
      GArray           *times;
      GArray           *zones;
      GstSDPKey         key;
      GArray           *attributes;
      GArray           *medias;
    } GstSDPMessage;

The contents of the SDP message.

gchar *`version`; | the protocol version
GstSDPOrigin `origin`; | owner/creator and session identifier
gchar *`session_name`; | session name
gchar *`information`; | session information
gchar *`uri`; | URI of description
GArray *`emails`; | array of gchar with email addresses
GArray *`phones`; | array of gchar with phone numbers
GstSDPConnection `connection`; | connection information for the session
GArray *`bandwidths`; | array of GstSDPBandwidth with bandwidth information
GArray *`times`; | array of GstSDPTime with time descriptions
GArray *`zones`; | array of GstSDPZone with time zone adjustments
GstSDPKey `key`; | encryption key
GArray *`attributes`; | array of GstSDPAttribute with session attributes
GArray *`medias`; | array of GstSDPMedia with media descriptions

### gst_sdp_message_new ()

    GstSDPResult        gst_sdp_message_new                 (GstSDPMessage **msg);

Allocate a new GstSDPMessage and store the result in `msg`.

`msg` : | pointer to new GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_init ()

    GstSDPResult        gst_sdp_message_init                (GstSDPMessage *msg);

Initialize `msg` so that its contents are as if it was freshly allocated with `gst_sdp_message_new()`. This function is mostly used to initialize a message allocated on the stack. `gst_sdp_message_uninit()` undoes this operation.

When this function is invoked on newly allocated data (with malloc or on the stack), its contents should be set to 0 before calling this function.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_uninit ()

    GstSDPResult        gst_sdp_message_uninit              (GstSDPMessage *msg);

Free all resources allocated in `msg`. `msg` should not be used anymore after this function. This function should be used when `msg` was allocated on the stack and initialized with `gst_sdp_message_init()`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_free ()

    GstSDPResult        gst_sdp_message_free                (GstSDPMessage *msg);

Free all resources allocated by `msg`. `msg` should not be used anymore after this function. This function should be used when `msg` was dynamically allocated with `gst_sdp_message_new()`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_parse_buffer ()

    GstSDPResult        gst_sdp_message_parse_buffer        (const guint8 *data,
                                                             guint size,
                                                             GstSDPMessage *msg);

Parse the contents of `size` bytes pointed to by `data` and store the result in `msg`.

`data` : | the start of the buffer
`size` : | the size of the buffer
`msg` : | the result GstSDPMessage
Returns : | GST_SDP_OK on success.

### gst_sdp_message_get_version ()

    const gchar*        gst_sdp_message_get_version         (const GstSDPMessage *msg);

Get the version in `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_set_version ()

    GstSDPResult        gst_sdp_message_set_version         (GstSDPMessage *msg,
                                                             const gchar *version);

Set the version in `msg`.

`msg` : | a GstSDPMessage
`version` : | the version
Returns : | a GstSDPResult.

### gst_sdp_message_get_origin ()

    const GstSDPOrigin* gst_sdp_message_get_origin          (const GstSDPMessage *msg);

Get the origin of `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPOrigin. The result remains valid as long as `msg` is valid.

### gst_sdp_message_set_origin ()

    GstSDPResult        gst_sdp_message_set_origin          (GstSDPMessage *msg,
                                                             const gchar *username,
                                                             const gchar *sess_id,
                                                             const gchar *sess_version,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *addr);

Configure the SDP origin in `msg` with the given parameters.

`msg` : | a GstSDPMessage
`username` : | the user name
`sess_id` : | a session id
`sess_version` : | a session version
`nettype` : | a network type
`addrtype` : | an address type
`addr` : | an address
Returns : | GST_SDP_OK.

### gst_sdp_message_get_session_name ()

    const gchar*        gst_sdp_message_get_session_name    (const GstSDPMessage *msg);

Get the session name in `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_set_session_name ()

    GstSDPResult        gst_sdp_message_set_session_name    (GstSDPMessage *msg,
                                                             const gchar *session_name);

Set the session name in `msg`.

`msg` : | a GstSDPMessage
`session_name` : | the session name
Returns : | a GstSDPResult.

### gst_sdp_message_get_information ()

    const gchar*        gst_sdp_message_get_information     (const GstSDPMessage *msg);

Get the information in `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_set_information ()

    GstSDPResult        gst_sdp_message_set_information     (GstSDPMessage *msg,
                                                             const gchar *information);

Set the information in `msg`.

`msg` : | a GstSDPMessage
`information` : | the information
Returns : | a GstSDPResult.

### gst_sdp_message_get_uri ()

    const gchar*        gst_sdp_message_get_uri             (const GstSDPMessage *msg);

Get the URI in `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_message_set_uri ()

    GstSDPResult        gst_sdp_message_set_uri             (GstSDPMessage *msg,
                                                             const gchar *uri);

Set the URI in `msg`.

`msg` : | a GstSDPMessage
`uri` : | the URI
Returns : | a GstSDPResult.

### gst_sdp_message_emails_len ()

    guint               gst_sdp_message_emails_len          (const GstSDPMessage *msg);

Get the number of emails in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of emails in `msg`.

### gst_sdp_message_get_email ()

    const gchar*        gst_sdp_message_get_email           (const GstSDPMessage *msg,
                                                             guint idx);

Get the email with number `idx` from `msg`.

`msg` : | a GstSDPMessage
`idx` : | an email index
Returns : | the email at position `idx`.

### gst_sdp_message_add_email ()

    GstSDPResult        gst_sdp_message_add_email           (GstSDPMessage *msg,
                                                             const gchar *email);

Add `email` to the list of emails in `msg`.

`msg` : | a GstSDPMessage
`email` : | an email
Returns : | a GstSDPResult.

### gst_sdp_message_phones_len ()

    guint               gst_sdp_message_phones_len          (const GstSDPMessage *msg);

Get the number of phones in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of phones in `msg`.

### gst_sdp_message_get_phone ()

    const gchar*        gst_sdp_message_get_phone           (const GstSDPMessage *msg,
                                                             guint idx);

Get the phone with number `idx` from `msg`.

`msg` : | a GstSDPMessage
`idx` : | a phone index
Returns : | the phone at position `idx`.

### gst_sdp_message_add_phone ()

    GstSDPResult        gst_sdp_message_add_phone           (GstSDPMessage *msg,
                                                             const gchar *phone);

Add `phone` to the list of phones in `msg`.

`msg` : | a GstSDPMessage
`phone` : | a phone
Returns : | a GstSDPResult.

### gst_sdp_message_get_connection ()

    const GstSDPConnection* gst_sdp_message_get_connection  (const GstSDPMessage *msg);

Get the connection of `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPConnection. The result remains valid as long as `msg` is valid.

### gst_sdp_message_set_connection ()

    GstSDPResult        gst_sdp_message_set_connection      (GstSDPMessage *msg,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *address,
                                                             guint ttl,
                                                             guint addr_number);

Configure the SDP connection in `msg` with the given parameters.

`msg` : | a GstSDPMessage
`nettype` : | the type of network. "IN" is defined to have the meaning "Internet".
`addrtype` : | the type of address.
`address` : | the address
`ttl` : | the time to live of the address
`addr_number` : | the number of layers
Returns : | a GstSDPResult.

### gst_sdp_message_bandwidths_len ()

    guint               gst_sdp_message_bandwidths_len      (const GstSDPMessage *msg);

Get the number of bandwidth information in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of bandwidth information in `msg`.

### gst_sdp_message_get_bandwidth ()

    const GstSDPBandwidth* gst_sdp_message_get_bandwidth    (const GstSDPMessage *msg,
                                                             guint idx);

Get the bandwidth at index `idx` from `msg`.

`msg` : | a GstSDPMessage
`idx` : | the bandwidth index
Returns : | a GstSDPBandwidth.

### gst_sdp_message_add_bandwidth ()

    GstSDPResult        gst_sdp_message_add_bandwidth       (GstSDPMessage *msg,
                                                             const gchar *bwtype,
                                                             guint bandwidth);

Add the specified bandwidth information to `msg`.

`msg` : | a GstSDPMessage
`bwtype` : | the bandwidth modifier type
`bandwidth` : | the bandwidth in kilobits per second
Returns : | a GstSDPResult.

### gst_sdp_message_times_len ()

    guint               gst_sdp_message_times_len           (const GstSDPMessage *msg);

Get the number of time information entries in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of time information entries in `msg`.

### gst_sdp_message_get_time ()

    const GstSDPTime*   gst_sdp_message_get_time            (const GstSDPMessage *msg,
                                                             guint idx);

Get time information with index `idx` from `msg`.

`msg` : | a GstSDPMessage
`idx` : | the time index
Returns : | a GstSDPTime.

### gst_sdp_message_add_time ()

    GstSDPResult        gst_sdp_message_add_time            (GstSDPMessage *msg,
                                                             const gchar *start,
                                                             const gchar *stop,
                                                             const gchar **repeat);

Add time information `start` and `stop` to `msg`.

`msg` : | a GstSDPMessage
`start` : | the start time
`stop` : | the stop time
`repeat` : | the repeat times
Returns : | a GstSDPResult.

### gst_sdp_message_zones_len ()

    guint               gst_sdp_message_zones_len           (const GstSDPMessage *msg);

Get the number of time zone information entries in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of time zone information entries in `msg`.

### gst_sdp_message_get_zone ()

    const GstSDPZone*   gst_sdp_message_get_zone            (const GstSDPMessage *msg,
                                                             guint idx);

Get time zone information with index `idx` from `msg`.

`msg` : | a GstSDPMessage
`idx` : | the zone index
Returns : | a GstSDPZone.

### gst_sdp_message_add_zone ()

    GstSDPResult        gst_sdp_message_add_zone            (GstSDPMessage *msg,
                                                             const gchar *adj_time,
                                                             const gchar *typed_time);

Add time zone information to `msg`.

`msg` : | a GstSDPMessage
`adj_time` : | the NTP time that a time zone adjustment happens
`typed_time` : | the offset from the time when the session was first scheduled
Returns : | a GstSDPResult.

### gst_sdp_message_get_key ()

    const GstSDPKey*    gst_sdp_message_get_key             (const GstSDPMessage *msg);

Get the encryption information from `msg`.

`msg` : | a GstSDPMessage
Returns : | a GstSDPKey.

### gst_sdp_message_set_key ()

    GstSDPResult        gst_sdp_message_set_key             (GstSDPMessage *msg,
                                                             const gchar *type,
                                                             const gchar *data);

Adds the encryption information to `msg`.

`msg` : | a GstSDPMessage
`type` : | the encryption type
`data` : | the encryption data
Returns : | a GstSDPResult.

### gst_sdp_message_attributes_len ()

    guint               gst_sdp_message_attributes_len      (const GstSDPMessage *msg);

Get the number of attributes in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of attributes in `msg`.

### gst_sdp_message_get_attribute ()

    const GstSDPAttribute* gst_sdp_message_get_attribute    (const GstSDPMessage *msg,
                                                             guint idx);

Get the attribute at position `idx` in `msg`.

`msg` : | a GstSDPMessage
`idx` : | the index
Returns : | the GstSDPAttribute at position `idx`.

### gst_sdp_message_get_attribute_val ()

    const gchar*        gst_sdp_message_get_attribute_val   (const GstSDPMessage *msg,
                                                             const gchar *key);

Get the first attribute with key `key` in `msg`.

`msg` : | a GstSDPMessage
`key` : | the key
Returns : | the attribute value of the first attribute with `key`.

### gst_sdp_message_get_attribute_val_n ()

    const gchar*        gst_sdp_message_get_attribute_val_n (const GstSDPMessage *msg,
                                                             const gchar *key,
                                                             guint nth);

Get the `nth` attribute with key `key` in `msg`.

`msg` : | a GstSDPMessage
`key` : | the key
`nth` : | the index
Returns : | the attribute value of the `nth` attribute with `key`.

### gst_sdp_message_add_attribute ()

    GstSDPResult        gst_sdp_message_add_attribute       (GstSDPMessage *msg,
                                                             const gchar *key,
                                                             const gchar *value);

Add the attribute with `key` and `value` to `msg`.

`msg` : | a GstSDPMessage
`key` : | the key
`value` : | the value
Returns : | `GST_SDP_OK`.

### gst_sdp_message_medias_len ()

    guint               gst_sdp_message_medias_len          (const GstSDPMessage *msg);

Get the number of media descriptions in `msg`.

`msg` : | a GstSDPMessage
Returns : | the number of media descriptions in `msg`.

### gst_sdp_message_get_media ()

    const GstSDPMedia*  gst_sdp_message_get_media           (const GstSDPMessage *msg,
                                                             guint idx);

Get the media description at index `idx` in `msg`.

`msg` : | a GstSDPMessage
`idx` : | the index
Returns : | a GstSDPMedia.

### gst_sdp_message_add_media ()

    GstSDPResult        gst_sdp_message_add_media           (GstSDPMessage *msg,
                                                             GstSDPMedia *media);

Adds `media` to the array of medias in `msg`. This function takes ownership of the contents of `media` so that `media` will have to be reinitialized with `gst_media_init()` before it can be used again.

`msg` : | a GstSDPMessage
`media` : | a GstSDPMedia to add
Returns : | a GstSDPResult.

### gst_sdp_message_dump ()

    GstSDPResult        gst_sdp_message_dump                (const GstSDPMessage *msg);

Dump the parsed contents of `msg` to stdout.

`msg` : | a GstSDPMessage
Returns : | a GstSDPResult.

### gst_sdp_media_new ()

    GstSDPResult        gst_sdp_media_new                   (GstSDPMedia **media);

Allocate a new GstSDPMedia and store the result in `media`.

`media` : | pointer to new GstSDPMedia
Returns : | a GstSDPResult.

### gst_sdp_media_init ()

    GstSDPResult        gst_sdp_media_init                  (GstSDPMedia *media);

Initialize `media` so that its contents are as if it was freshly allocated with `gst_sdp_media_new()`. This function is mostly used to initialize a media allocated on the stack. `gst_sdp_media_uninit()` undoes this operation.

When this function is invoked on newly allocated data (with malloc or on the stack), its contents should be set to 0 before calling this function.

`media` : | a GstSDPMedia
Returns : | a GstSDPResult.

### gst_sdp_media_uninit ()

    GstSDPResult        gst_sdp_media_uninit                (GstSDPMedia *media);

Free all resources allocated in `media`. `media` should not be used anymore after this function. This function should be used when `media` was allocated on the stack and initialized with `gst_sdp_media_init()`.

`media` : | a GstSDPMedia
Returns : | a GstSDPResult.

### gst_sdp_media_free ()

    GstSDPResult        gst_sdp_media_free                  (GstSDPMedia *media);

Free all resources allocated by `media`. `media` should not be used anymore after this function. This function should be used when `media` was dynamically allocated with `gst_sdp_media_new()`.

`media` : | a GstSDPMedia
Returns : | a GstSDPResult.

### gst_sdp_media_get_media ()

    const gchar*        gst_sdp_media_get_media             (const GstSDPMedia *media);

Get the media description of `media`.

`media` : | a GstSDPMedia
Returns : | the media description.

### gst_sdp_media_set_media ()

    GstSDPResult        gst_sdp_media_set_media             (GstSDPMedia *media,
                                                             const gchar *med);

Set the media description of `media` to `med`.

`media` : | a GstSDPMedia
`med` : | the media description
Returns : | GST_SDP_OK.

### gst_sdp_media_get_port ()

    guint               gst_sdp_media_get_port              (const GstSDPMedia *media);

Get the port number for `media`.

`media` : | a GstSDPMedia
Returns : | the port number of `media`.

### gst_sdp_media_get_num_ports ()

    guint               gst_sdp_media_get_num_ports         (const GstSDPMedia *media);

Get the number of ports for `media`.

`media` : | a GstSDPMedia
Returns : | the number of ports for `media`.

### gst_sdp_media_set_port_info ()

    GstSDPResult        gst_sdp_media_set_port_info         (GstSDPMedia *media,
                                                             guint port,
                                                             guint num_ports);

Set the port information in `media`.

`media` : | a GstSDPMedia
`port` : | the port number
`num_ports` : | the number of ports
Returns : | GST_SDP_OK.

### gst_sdp_media_get_proto ()

    const gchar*        gst_sdp_media_get_proto             (const GstSDPMedia *media);

Get the transport protocol of `media`

`media` : | a GstSDPMedia
Returns : | the transport protocol of `media`.

### gst_sdp_media_set_proto ()

    GstSDPResult        gst_sdp_media_set_proto             (GstSDPMedia *media,
                                                             const gchar *proto);

Set the media transport protocol of `media` to `proto`.

`media` : | a GstSDPMedia
`proto` : | the media transport protocol
Returns : | GST_SDP_OK.

### gst_sdp_media_formats_len ()

    guint               gst_sdp_media_formats_len           (const GstSDPMedia *media);

Get the number of formats in `media`.

`media` : | a GstSDPMedia
Returns : | the number of formats in `media`.

### gst_sdp_media_get_format ()

    const gchar*        gst_sdp_media_get_format            (const GstSDPMedia *media,
                                                             guint idx);

Get the format information at position `idx` in `media`.

`media` : | a GstSDPMedia
`idx` : | an index
Returns : | the format at position `idx`.

### gst_sdp_media_add_format ()

    GstSDPResult        gst_sdp_media_add_format            (GstSDPMedia *media,
                                                             const gchar *format);

Add the format information to `media`.

`media` : | a GstSDPMedia
`format` : | the format
Returns : | GST_SDP_OK.

### gst_sdp_media_get_information ()

    const gchar*        gst_sdp_media_get_information       (const GstSDPMedia *media);

Get the information of `media`

`media` : | a GstSDPMedia
Returns : | the information of `media`.

### gst_sdp_media_set_information ()

    GstSDPResult        gst_sdp_media_set_information       (GstSDPMedia *media,
                                                             const gchar *information);

Set the media information of `media` to `information`.

`media` : | a GstSDPMedia
`information` : | the media information
Returns : | GST_SDP_OK.

### gst_sdp_media_connections_len ()

    guint               gst_sdp_media_connections_len       (const GstSDPMedia *media);

Get the number of connection fields in `media`.

`media` : | a GstSDPMedia
Returns : | the number of connections in `media`.

### gst_sdp_media_get_connection ()

    const GstSDPConnection* gst_sdp_media_get_connection    (const GstSDPMedia *media,
                                                             guint idx);

Get the connection at position `idx` in `media`.

`media` : | a GstSDPMedia
`idx` : | an index
Returns : | the GstSDPConnection at position `idx`.

### gst_sdp_media_add_connection ()

    GstSDPResult        gst_sdp_media_add_connection        (GstSDPMedia *media,
                                                             const gchar *nettype,
                                                             const gchar *addrtype,
                                                             const gchar *address,
                                                             guint ttl,
                                                             guint addr_number);

Add the given connection parameters to `media`.

`media` : | a GstSDPMedia
`nettype` : | the type of network. "IN" is defined to have the meaning "Internet".
`addrtype` : | the type of address.
`address` : | the address
`ttl` : | the time to live of the address
`addr_number` : | the number of layers
Returns : | a GstSDPResult.

### gst_sdp_media_bandwidths_len ()

    guint               gst_sdp_media_bandwidths_len        (const GstSDPMedia *media);

Get the number of bandwidth fields in `media`.

`media` : | a GstSDPMedia
Returns : | the number of bandwidths in `media`.

### gst_sdp_media_get_bandwidth ()

    const GstSDPBandwidth* gst_sdp_media_get_bandwidth      (const GstSDPMedia *media,
                                                             guint idx);

Get the bandwidth at position `idx` in `media`.

`media` : | a GstSDPMedia
`idx` : | an index
Returns : | the GstSDPBandwidth at position `idx`.

### gst_sdp_media_add_bandwidth ()

    GstSDPResult        gst_sdp_media_add_bandwidth         (GstSDPMedia *media,
                                                             const gchar *bwtype,
                                                             guint bandwidth);

Add the bandwidth information with `bwtype` and `bandwidth` to `media`.

`media` : | a GstSDPMedia
`bwtype` : | the bandwidth modifier type
`bandwidth` : | the bandwidth in kilobits per second
Returns : | GST_SDP_OK.

### gst_sdp_media_get_key ()

    const GstSDPKey*    gst_sdp_media_get_key               (const GstSDPMedia *media);

Get the encryption information from `media`.

`media` : | a GstSDPMedia
Returns : | a GstSDPKey.

### gst_sdp_media_set_key ()

    GstSDPResult        gst_sdp_media_set_key               (GstSDPMedia *media,
                                                             const gchar *type,
                                                             const gchar *data);

Adds the encryption information to `media`.

`media` : | a GstSDPMedia
`type` : | the encryption type
`data` : | the encryption data
Returns : | a GstSDPResult.

### gst_sdp_media_attributes_len ()

    guint               gst_sdp_media_attributes_len        (const GstSDPMedia *media);

Get the number of attribute fields in `media`.

`media` : | a GstSDPMedia
Returns : | the number of attributes in `media`.

### gst_sdp_media_get_attribute ()

    const GstSDPAttribute* gst_sdp_media_get_attribute      (const GstSDPMedia *media,
                                                             guint idx);

Get the attribute at position `idx` in `media`.

`media` : | a GstSDPMedia
`idx` : | an index
Returns : | the GstSDPAttribute at position `idx`.

### gst_sdp_media_get_attribute_val ()

    const gchar*        gst_sdp_media_get_attribute_val     (const GstSDPMedia *media,
                                                             const gchar *key);

Get the first attribute value for `key` in `media`.

`media` : | a GstSDPMedia
`key` : | a key
Returns : | the first attribute value for `key`.

### gst_sdp_media_get_attribute_val_n ()

    const gchar*        gst_sdp_media_get_attribute_val_n   (const GstSDPMedia *media,
                                                             const gchar *key,
                                                             guint nth);

Get the `nth` attribute value for `key` in `media`.

`media` : | a GstSDPMedia
`key` : | a key
`nth` : | an index
Returns : | the `nth` attribute value.

### gst_sdp_media_add_attribute ()

    GstSDPResult        gst_sdp_media_add_attribute         (GstSDPMedia *media,
                                                             const gchar *key,
                                                             const gchar *value);

Add the attribute with `key` and `value` to `media`.

`media` : | a GstSDPMedia
`key` : | a key
`value` : | a value
Returns : | GST_SDP_OK.