/* GStreamer
* Copyright (C) <2007> Wim Taymans <wim@fluendo.com>
*
* gstrtcpbuffer.h: various helper functions to manipulate buffers
* with RTCP payload.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstrtcpbuffer
* @title: GstRTCPBuffer
* @short_description: Helper methods for dealing with RTCP buffers
* @see_also: #GstRTPBasePayload, #GstRTPBaseDepayload, #gstrtpbuffer
*
* Note: The API in this module is not yet declared stable.
*
* The GstRTPCBuffer helper functions makes it easy to parse and create regular
* #GstBuffer objects that contain compound RTCP packets. These buffers are typically
* of 'application/x-rtcp' #GstCaps.
*
* An RTCP buffer consists of 1 or more #GstRTCPPacket structures that you can
* retrieve with gst_rtcp_buffer_get_first_packet(). #GstRTCPPacket acts as a pointer
* into the RTCP buffer; you can move to the next packet with
* gst_rtcp_packet_move_to_next().
*
*/
#include <string.h>
#include "gstrtcpbuffer.h"
/**
* gst_rtcp_buffer_new_take_data:
* @data: (array length=len) (element-type guint8): data for the new buffer
* @len: the length of data
*
* Create a new buffer and set the data and size of the buffer to @data and @len
* respectively. @data will be freed when the buffer is unreffed, so this
* function transfers ownership of @data to the new buffer.
*
* Returns: A newly allocated buffer with @data and of size @len.
*/
GstBuffer *
gst_rtcp_buffer_new_take_data (gpointer data, guint len)
{
GstBuffer *result;
g_return_val_if_fail (data != NULL, NULL);
g_return_val_if_fail (len > 0, NULL);
result = gst_buffer_new_wrapped (data, len);
return result;
}
/**
* gst_rtcp_buffer_new_copy_data:
* @data: (array length=len) (element-type guint8): data for the new buffer
* @len: the length of data
*
* Create a new buffer and set the data to a copy of @len
* bytes of @data and the size to @len. The data will be freed when the buffer
* is freed.
*
* Returns: A newly allocated buffer with a copy of @data and of size @len.
*/
GstBuffer *
gst_rtcp_buffer_new_copy_data (gconstpointer data, guint len)
{
return gst_rtcp_buffer_new_take_data (g_memdup (data, len), len);
}
static gboolean
gst_rtcp_buffer_validate_data_internal (guint8 * data, guint len,
guint16 valid_mask)
{
guint16 header_mask;
guint header_len;
guint8 version;
guint data_len;
gboolean padding;
guint8 pad_bytes;
g_return_val_if_fail (data != NULL, FALSE);
/* we need 4 bytes for the type and length */
if (G_UNLIKELY (len < 4))
goto wrong_length;
/* first packet must be RR or SR and version must be 2 */
header_mask = ((data[0] << 8) | data[1]) & valid_mask;
if (G_UNLIKELY (header_mask != GST_RTCP_VALID_VALUE))
goto wrong_mask;
/* no padding when mask succeeds */
padding = FALSE;
/* store len */
data_len = len;
while (TRUE) {
/* get packet length */
header_len = (((data[2] << 8) | data[3]) + 1) << 2;
if (data_len < header_len)
goto wrong_length;
/* move to next compount packet */
data += header_len;
data_len -= header_len;
/* we are at the end now */
if (data_len < 4)
break;
/* padding only allowed on last packet */
if (padding)
break;
/* check version of new packet */
version = data[0] & 0xc0;
if (version != (GST_RTCP_VERSION << 6))
goto wrong_version;
/* check padding of new packet */
if (data[0] & 0x20) {
padding = TRUE;
/* last byte of padding contains the number of padded bytes including
* itself. must be a multiple of 4, but cannot be 0. */
pad_bytes = data[data_len - 1];
if (pad_bytes == 0 || (pad_bytes & 0x3))
goto wrong_padding;
}
}
if (data_len != 0) {
/* some leftover bytes */
goto wrong_length;
}
return TRUE;
/* ERRORS */
wrong_length:
{
GST_DEBUG ("len check failed");
return FALSE;
}
wrong_mask:
{
GST_DEBUG ("mask check failed (%04x != %04x)", header_mask, valid_mask);
return FALSE;
}
wrong_version:
{
GST_DEBUG ("wrong version (%d < 2)", version >> 6);
return FALSE;
}
wrong_padding:
{
GST_DEBUG ("padding check failed");
return FALSE;
}
}
/**
* gst_rtcp_buffer_validate_data_reduced:
* @data: (array length=len): the data to validate
* @len: the length of @data to validate
*
* Check if the @data and @size point to the data of a valid RTCP packet.
* Use this function to validate a packet before using the other functions in
* this module.
*
* This function is updated to support reduced size rtcp packets according to
* RFC 5506 and will validate full compound RTCP packets as well as reduced
* size RTCP packets.
*
* Returns: TRUE if the data points to a valid RTCP packet.
*
* Since: 1.6
*/
gboolean
gst_rtcp_buffer_validate_data_reduced (guint8 * data, guint len)
{
return gst_rtcp_buffer_validate_data_internal (data, len,
GST_RTCP_REDUCED_SIZE_VALID_MASK);
}
/**
* gst_rtcp_buffer_validate_data:
* @data: (array length=len): the data to validate
* @len: the length of @data to validate
*
* Check if the @data and @size point to the data of a valid compound,
* non-reduced size RTCP packet.
* Use this function to validate a packet before using the other functions in
* this module.
*
* Returns: TRUE if the data points to a valid RTCP packet.
*/
gboolean
gst_rtcp_buffer_validate_data (guint8 * data, guint len)
{
return gst_rtcp_buffer_validate_data_internal (data, len,
GST_RTCP_VALID_MASK);
}
/**
* gst_rtcp_buffer_validate_reduced:
* @buffer: the buffer to validate
*
* Check if the data pointed to by @buffer is a valid RTCP packet using
* gst_rtcp_buffer_validate_reduced().
*
* Returns: TRUE if @buffer is a valid RTCP packet.
*
* Since: 1.6
*/
gboolean
gst_rtcp_buffer_validate_reduced (GstBuffer * buffer)
{
gboolean res;
GstMapInfo map;
g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
gst_buffer_map (buffer, &map, GST_MAP_READ);
res = gst_rtcp_buffer_validate_data_reduced (map.data, map.size);
gst_buffer_unmap (buffer, &map);
return res;
}
/**
* gst_rtcp_buffer_validate:
* @buffer: the buffer to validate
*
* Check if the data pointed to by @buffer is a valid RTCP packet using
* gst_rtcp_buffer_validate_data().
*
* Returns: TRUE if @buffer is a valid RTCP packet.
*/
gboolean
gst_rtcp_buffer_validate (GstBuffer * buffer)
{
gboolean res;
GstMapInfo map;
g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
gst_buffer_map (buffer, &map, GST_MAP_READ);
res = gst_rtcp_buffer_validate_data (map.data, map.size);
gst_buffer_unmap (buffer, &map);
return res;
}
/**
* gst_rtcp_buffer_new:
* @mtu: the maximum mtu size.
*
* Create a new buffer for constructing RTCP packets. The packet will have a
* maximum size of @mtu.
*
* Returns: A newly allocated buffer.
*/
GstBuffer *
gst_rtcp_buffer_new (guint mtu)
{
GstBuffer *result;
guint8 *data;
g_return_val_if_fail (mtu > 0, NULL);
data = g_malloc0 (mtu);
result = gst_buffer_new_wrapped_full (0, data, mtu, 0, 0, data, g_free);
return result;
}
/**
* gst_rtcp_buffer_map:
* @buffer: a buffer with an RTCP packet
* @flags: flags for the mapping
* @rtcp: resulting #GstRTCPBuffer
*
* Open @buffer for reading or writing, depending on @flags. The resulting RTCP
* buffer state is stored in @rtcp.
*/
gboolean
gst_rtcp_buffer_map (GstBuffer * buffer, GstMapFlags flags,
GstRTCPBuffer * rtcp)
{
g_return_val_if_fail (rtcp != NULL, FALSE);
g_return_val_if_fail (rtcp->buffer == NULL, FALSE);
g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
g_return_val_if_fail (flags & GST_MAP_READ, FALSE);
rtcp->buffer = buffer;
gst_buffer_map (buffer, &rtcp->map, flags);
return TRUE;
}
/**
* gst_rtcp_buffer_unmap:
* @rtcp: a buffer with an RTCP packet
*
* Finish @rtcp after being constructed. This function is usually called
* after gst_rtcp_buffer_map() and after adding the RTCP items to the new buffer.
*
* The function adjusts the size of @rtcp with the total length of all the
* added packets.
*/
gboolean
gst_rtcp_buffer_unmap (GstRTCPBuffer * rtcp)
{
g_return_val_if_fail (rtcp != NULL, FALSE);
g_return_val_if_fail (GST_IS_BUFFER (rtcp->buffer), FALSE);
if (rtcp->map.flags & GST_MAP_WRITE) {
/* shrink size */
gst_buffer_resize (rtcp->buffer, 0, rtcp->map.size);
}
gst_buffer_unmap (rtcp->buffer, &rtcp->map);
rtcp->buffer = NULL;
return TRUE;
}
/**
* gst_rtcp_buffer_get_packet_count:
* @rtcp: a valid RTCP buffer
*
* Get the number of RTCP packets in @rtcp.
*
* Returns: the number of RTCP packets in @rtcp.
*/
guint
gst_rtcp_buffer_get_packet_count (GstRTCPBuffer * rtcp)
{
GstRTCPPacket packet;
guint count;
g_return_val_if_fail (rtcp != NULL, 0);
g_return_val_if_fail (GST_IS_BUFFER (rtcp->buffer), 0);
g_return_val_if_fail (rtcp != NULL, 0);
g_return_val_if_fail (rtcp->map.flags & GST_MAP_READ, 0);
count = 0;
if (gst_rtcp_buffer_get_first_packet (rtcp, &packet)) {
do {
count++;
} while (gst_rtcp_packet_move_to_next (&packet));
}
return count;
}
/**
* read_packet_header:
* @packet: a packet
*
* Read the packet headers for the packet pointed to by @packet.
*
* Returns: TRUE if @packet pointed to a valid header.
*/
static gboolean
read_packet_header (GstRTCPPacket * packet)
{
guint8 *data;
gsize maxsize;
guint offset;
g_return_val_if_fail (packet != NULL, FALSE);
data = packet->rtcp->map.data;
maxsize = packet->rtcp->map.size;
offset = packet->offset;
/* check if we are at the end of the buffer, we add 4 because we also want to
* ensure we can read the header. */
if (offset + 4 > maxsize)
return FALSE;
if ((data[offset] & 0xc0) != (GST_RTCP_VERSION << 6))
return FALSE;
/* read count, type and length */
packet->padding = (data[offset] & 0x20) == 0x20;
packet->count = data[offset] & 0x1f;
packet->type = data[offset + 1];
packet->length = (data[offset + 2] << 8) | data[offset + 3];
packet->item_offset = 4;
packet->item_count = 0;
packet->entry_offset = 4;
/* Ensure no overread from the claimed data size. The packet length
is expressed in multiple of 32 bits, to make things obvious. */
if (offset + 4 + packet->length * 4 > maxsize)
return FALSE;
return TRUE;
}
/**
* gst_rtcp_buffer_get_first_packet:
* @rtcp: a valid RTCP buffer
* @packet: a #GstRTCPPacket
*
* Initialize a new #GstRTCPPacket pointer that points to the first packet in
* @rtcp.
*
* Returns: TRUE if the packet existed in @rtcp.
*/
gboolean
gst_rtcp_buffer_get_first_packet (GstRTCPBuffer * rtcp, GstRTCPPacket * packet)
{
g_return_val_if_fail (rtcp != NULL, FALSE);
g_return_val_if_fail (GST_IS_BUFFER (rtcp->buffer), FALSE);
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (rtcp != NULL, 0);
g_return_val_if_fail (rtcp->map.flags & GST_MAP_READ, 0);
/* init to 0 */
packet->rtcp = rtcp;
packet->offset = 0;
packet->type = GST_RTCP_TYPE_INVALID;
if (!read_packet_header (packet))
return FALSE;
return TRUE;
}
/**
* gst_rtcp_packet_move_to_next:
* @packet: a #GstRTCPPacket
*
* Move the packet pointer @packet to the next packet in the payload.
* Use gst_rtcp_buffer_get_first_packet() to initialize @packet.
*
* Returns: TRUE if @packet is pointing to a valid packet after calling this
* function.
*/
gboolean
gst_rtcp_packet_move_to_next (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type != GST_RTCP_TYPE_INVALID, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
/* if we have a padding or invalid packet, it must be the last,
* return FALSE */
if (packet->type == GST_RTCP_TYPE_INVALID || packet->padding)
goto end;
/* move to next packet. Add 4 because the header is not included in length */
packet->offset += (packet->length << 2) + 4;
/* try to read new header */
if (!read_packet_header (packet))
goto end;
return TRUE;
/* ERRORS */
end:
{
packet->type = GST_RTCP_TYPE_INVALID;
return FALSE;
}
}
/**
* gst_rtcp_buffer_add_packet:
* @rtcp: a valid RTCP buffer
* @type: the #GstRTCPType of the new packet
* @packet: pointer to new packet
*
* Add a new packet of @type to @rtcp. @packet will point to the newly created
* packet.
*
* Returns: %TRUE if the packet could be created. This function returns %FALSE
* if the max mtu is exceeded for the buffer.
*/
gboolean
gst_rtcp_buffer_add_packet (GstRTCPBuffer * rtcp, GstRTCPType type,
GstRTCPPacket * packet)
{
guint len;
gsize maxsize;
guint8 *data;
gboolean result;
g_return_val_if_fail (rtcp != NULL, FALSE);
g_return_val_if_fail (GST_IS_BUFFER (rtcp->buffer), FALSE);
g_return_val_if_fail (type != GST_RTCP_TYPE_INVALID, FALSE);
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (rtcp->map.flags & GST_MAP_WRITE, FALSE);
/* find free space */
if (gst_rtcp_buffer_get_first_packet (rtcp, packet))
while (gst_rtcp_packet_move_to_next (packet));
maxsize = rtcp->map.maxsize;
/* packet->offset is now pointing to the next free offset in the buffer to
* start a compount packet. Next we figure out if we have enough free space in
* the buffer to continue. */
switch (type) {
case GST_RTCP_TYPE_SR:
len = 28;
break;
case GST_RTCP_TYPE_RR:
len = 8;
break;
case GST_RTCP_TYPE_SDES:
len = 4;
break;
case GST_RTCP_TYPE_BYE:
len = 4;
break;
case GST_RTCP_TYPE_APP:
len = 12;
break;
case GST_RTCP_TYPE_RTPFB:
len = 12;
break;
case GST_RTCP_TYPE_PSFB:
len = 12;
break;
case GST_RTCP_TYPE_XR:
len = 4;
break;
default:
goto unknown_type;
}
if (packet->offset + len >= maxsize)
goto no_space;
rtcp->map.size += len;
data = rtcp->map.data + packet->offset;
data[0] = (GST_RTCP_VERSION << 6);
data[1] = type;
/* length is stored in multiples of 32 bit words minus the length of the
* header */
len = (len - 4) >> 2;
data[2] = len >> 8;
data[3] = len & 0xff;
/* now try to position to the packet */
result = read_packet_header (packet);
return result;
/* ERRORS */
unknown_type:
{
g_warning ("unknown type %d", type);
return FALSE;
}
no_space:
{
return FALSE;
}
}
/**
* gst_rtcp_packet_remove:
* @packet: a #GstRTCPPacket
*
* Removes the packet pointed to by @packet and moves pointer to the next one
*
* Returns: TRUE if @packet is pointing to a valid packet after calling this
* function.
*/
gboolean
gst_rtcp_packet_remove (GstRTCPPacket * packet)
{
gboolean ret = FALSE;
guint offset = 0;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type != GST_RTCP_TYPE_INVALID, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
/* The next packet starts at offset + length + 4 (the header) */
offset = packet->offset + (packet->length << 2) + 4;
/* Overwrite this packet with the rest of the data */
memmove (packet->rtcp->map.data + packet->offset,
packet->rtcp->map.data + offset, packet->rtcp->map.size - offset);
packet->rtcp->map.size -= offset - packet->offset;
/* try to read next header */
ret = read_packet_header (packet);
if (!ret)
packet->type = GST_RTCP_TYPE_INVALID;
return ret;
}
/**
* gst_rtcp_packet_get_padding:
* @packet: a valid #GstRTCPPacket
*
* Get the packet padding of the packet pointed to by @packet.
*
* Returns: If the packet has the padding bit set.
*/
gboolean
gst_rtcp_packet_get_padding (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type != GST_RTCP_TYPE_INVALID, FALSE);
return packet->padding;
}
/**
* gst_rtcp_packet_get_type:
* @packet: a valid #GstRTCPPacket
*
* Get the packet type of the packet pointed to by @packet.
*
* Returns: The packet type or GST_RTCP_TYPE_INVALID when @packet is not
* pointing to a valid packet.
*/
GstRTCPType
gst_rtcp_packet_get_type (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, GST_RTCP_TYPE_INVALID);
return packet->type;
}
/**
* gst_rtcp_packet_get_count:
* @packet: a valid #GstRTCPPacket
*
* Get the count field in @packet.
*
* Returns: The count field in @packet or -1 if @packet does not point to a
* valid packet.
*/
guint8
gst_rtcp_packet_get_count (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, -1);
g_return_val_if_fail (packet->type != GST_RTCP_TYPE_INVALID, -1);
return packet->count;
}
/**
* gst_rtcp_packet_get_length:
* @packet: a valid #GstRTCPPacket
*
* Get the length field of @packet. This is the length of the packet in
* 32-bit words minus one.
*
* Returns: The length field of @packet.
*/
guint16
gst_rtcp_packet_get_length (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type != GST_RTCP_TYPE_INVALID, 0);
return packet->length;
}
/**
* gst_rtcp_packet_sr_get_sender_info:
* @packet: a valid SR #GstRTCPPacket
* @ssrc: (out): result SSRC
* @ntptime: (out): result NTP time
* @rtptime: (out): result RTP time
* @packet_count: (out): result packet count
* @octet_count: (out): result octet count
*
* Parse the SR sender info and store the values.
*/
void
gst_rtcp_packet_sr_get_sender_info (GstRTCPPacket * packet, guint32 * ssrc,
guint64 * ntptime, guint32 * rtptime, guint32 * packet_count,
guint32 * octet_count)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_SR);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_READ);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
if (ssrc)
*ssrc = GST_READ_UINT32_BE (data);
data += 4;
if (ntptime)
*ntptime = GST_READ_UINT64_BE (data);
data += 8;
if (rtptime)
*rtptime = GST_READ_UINT32_BE (data);
data += 4;
if (packet_count)
*packet_count = GST_READ_UINT32_BE (data);
data += 4;
if (octet_count)
*octet_count = GST_READ_UINT32_BE (data);
}
/**
* gst_rtcp_packet_sr_set_sender_info:
* @packet: a valid SR #GstRTCPPacket
* @ssrc: the SSRC
* @ntptime: the NTP time
* @rtptime: the RTP time
* @packet_count: the packet count
* @octet_count: the octet count
*
* Set the given values in the SR packet @packet.
*/
void
gst_rtcp_packet_sr_set_sender_info (GstRTCPPacket * packet, guint32 ssrc,
guint64 ntptime, guint32 rtptime, guint32 packet_count, guint32 octet_count)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_SR);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
GST_WRITE_UINT32_BE (data, ssrc);
data += 4;
GST_WRITE_UINT64_BE (data, ntptime);
data += 8;
GST_WRITE_UINT32_BE (data, rtptime);
data += 4;
GST_WRITE_UINT32_BE (data, packet_count);
data += 4;
GST_WRITE_UINT32_BE (data, octet_count);
}
/**
* gst_rtcp_packet_rr_get_ssrc:
* @packet: a valid RR #GstRTCPPacket
*
* Get the ssrc field of the RR @packet.
*
* Returns: the ssrc.
*/
guint32
gst_rtcp_packet_rr_get_ssrc (GstRTCPPacket * packet)
{
guint8 *data;
guint32 ssrc;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
ssrc = GST_READ_UINT32_BE (data);
return ssrc;
}
/**
* gst_rtcp_packet_rr_set_ssrc:
* @packet: a valid RR #GstRTCPPacket
* @ssrc: the SSRC to set
*
* Set the ssrc field of the RR @packet.
*/
void
gst_rtcp_packet_rr_set_ssrc (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RR);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
GST_WRITE_UINT32_BE (data, ssrc);
}
/**
* gst_rtcp_packet_get_rb_count:
* @packet: a valid SR or RR #GstRTCPPacket
*
* Get the number of report blocks in @packet.
*
* Returns: The number of report blocks in @packet.
*/
guint
gst_rtcp_packet_get_rb_count (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
return packet->count;
}
/**
* gst_rtcp_packet_get_rb:
* @packet: a valid SR or RR #GstRTCPPacket
* @nth: the nth report block in @packet
* @ssrc: (out): result for data source being reported
* @fractionlost: (out): result for fraction lost since last SR/RR
* @packetslost: (out): result for the cumululative number of packets lost
* @exthighestseq: (out): result for the extended last sequence number received
* @jitter: (out): result for the interarrival jitter
* @lsr: (out): result for the last SR packet from this source
* @dlsr: (out): result for the delay since last SR packet
*
* Parse the values of the @nth report block in @packet and store the result in
* the values.
*/
void
gst_rtcp_packet_get_rb (GstRTCPPacket * packet, guint nth, guint32 * ssrc,
guint8 * fractionlost, gint32 * packetslost, guint32 * exthighestseq,
guint32 * jitter, guint32 * lsr, guint32 * dlsr)
{
guint offset;
guint8 *data;
guint32 tmp;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_READ);
g_return_if_fail (nth < packet->count);
/* get offset in 32-bits words into packet, skip the header */
if (packet->type == GST_RTCP_TYPE_RR)
offset = 2;
else
offset = 7;
/* move to requested index */
offset += (nth * 6);
/* check that we don't go past the packet length */
if (offset > packet->length)
return;
/* scale to bytes */
offset <<= 2;
offset += packet->offset;
/* check if the packet is valid */
if (offset + 24 > packet->rtcp->map.size)
return;
data = packet->rtcp->map.data;
data += offset;
if (ssrc)
*ssrc = GST_READ_UINT32_BE (data);
data += 4;
tmp = GST_READ_UINT32_BE (data);
if (fractionlost)
*fractionlost = (tmp >> 24);
if (packetslost) {
/* sign extend */
if (tmp & 0x00800000)
tmp |= 0xff000000;
else
tmp &= 0x00ffffff;
*packetslost = (gint32) tmp;
}
data += 4;
if (exthighestseq)
*exthighestseq = GST_READ_UINT32_BE (data);
data += 4;
if (jitter)
*jitter = GST_READ_UINT32_BE (data);
data += 4;
if (lsr)
*lsr = GST_READ_UINT32_BE (data);
data += 4;
if (dlsr)
*dlsr = GST_READ_UINT32_BE (data);
}
/**
* gst_rtcp_packet_add_rb:
* @packet: a valid SR or RR #GstRTCPPacket
* @ssrc: data source being reported
* @fractionlost: fraction lost since last SR/RR
* @packetslost: the cumululative number of packets lost
* @exthighestseq: the extended last sequence number received
* @jitter: the interarrival jitter
* @lsr: the last SR packet from this source
* @dlsr: the delay since last SR packet
*
* Add a new report block to @packet with the given values.
*
* Returns: %TRUE if the packet was created. This function can return %FALSE if
* the max MTU is exceeded or the number of report blocks is greater than
* #GST_RTCP_MAX_RB_COUNT.
*/
gboolean
gst_rtcp_packet_add_rb (GstRTCPPacket * packet, guint32 ssrc,
guint8 fractionlost, gint32 packetslost, guint32 exthighestseq,
guint32 jitter, guint32 lsr, guint32 dlsr)
{
guint8 *data;
guint maxsize, offset;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
/* if profile-specific extension is added, fail for now!? */
g_return_val_if_fail (gst_rtcp_packet_get_profile_specific_ext_length (packet)
== 0, FALSE);
if (packet->count >= GST_RTCP_MAX_RB_COUNT)
goto no_space;
data = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
/* skip header */
offset = packet->offset + 4;
if (packet->type == GST_RTCP_TYPE_RR)
offset += 4;
else
offset += 24;
/* move to current index */
offset += (packet->count * 24);
/* we need 24 free bytes now */
if (offset + 24 >= maxsize)
goto no_space;
/* increment packet count and length */
packet->count++;
data[packet->offset]++;
packet->length += 6;
data[packet->offset + 2] = (packet->length) >> 8;
data[packet->offset + 3] = (packet->length) & 0xff;
packet->rtcp->map.size += 6 * 4;
/* move to new report block offset */
data += offset;
GST_WRITE_UINT32_BE (data, ssrc);
data += 4;
GST_WRITE_UINT32_BE (data,
((guint32) fractionlost << 24) | (packetslost & 0xffffff));
data += 4;
GST_WRITE_UINT32_BE (data, exthighestseq);
data += 4;
GST_WRITE_UINT32_BE (data, jitter);
data += 4;
GST_WRITE_UINT32_BE (data, lsr);
data += 4;
GST_WRITE_UINT32_BE (data, dlsr);
return TRUE;
no_space:
{
return FALSE;
}
}
/**
* gst_rtcp_packet_set_rb:
* @packet: a valid SR or RR #GstRTCPPacket
* @nth: the nth report block to set
* @ssrc: data source being reported
* @fractionlost: fraction lost since last SR/RR
* @packetslost: the cumululative number of packets lost
* @exthighestseq: the extended last sequence number received
* @jitter: the interarrival jitter
* @lsr: the last SR packet from this source
* @dlsr: the delay since last SR packet
*
* Set the @nth new report block in @packet with the given values.
*
* Note: Not implemented.
*/
void
gst_rtcp_packet_set_rb (GstRTCPPacket * packet, guint nth, guint32 ssrc,
guint8 fractionlost, gint32 packetslost, guint32 exthighestseq,
guint32 jitter, guint32 lsr, guint32 dlsr)
{
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
g_warning ("not implemented");
}
/**
* gst_rtcp_packet_add_profile_specific_ext:
* @packet: a valid SR or RR #GstRTCPPacket
* @data: (array length=len) (transfer none): profile-specific data
* @len: length of the profile-specific data in bytes
*
* Add profile-specific extension @data to @packet. If @packet already
* contains profile-specific extension @data will be appended to the existing
* extension.
*
* Returns: %TRUE if the profile specific extension data was added.
*/
gboolean
gst_rtcp_packet_add_profile_specific_ext (GstRTCPPacket * packet,
const guint8 * data, guint len)
{
guint8 *bdata;
guint maxsize, offset;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
g_return_val_if_fail ((len & 0x03) == 0, FALSE);
bdata = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
/* skip to the end of the packet */
offset = packet->offset + (packet->length << 2) + 4;
/* we need 'len' free bytes now */
if (G_UNLIKELY (offset + len > maxsize))
return FALSE;
memcpy (&bdata[offset], data, len);
packet->length += len >> 2;
bdata[packet->offset + 2] = (packet->length) >> 8;
bdata[packet->offset + 3] = (packet->length) & 0xff;
packet->rtcp->map.size += len;
return TRUE;
}
/**
* gst_rtcp_packet_get_profile_specific_ext_length:
* @packet: a valid SR or RR #GstRTCPPacket
*
* Returns: The number of 32-bit words containing profile-specific extension
* data from @packet.
*/
guint16
gst_rtcp_packet_get_profile_specific_ext_length (GstRTCPPacket * packet)
{
guint pse_offset = 2;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
if (packet->type == GST_RTCP_TYPE_SR)
pse_offset += 5;
pse_offset += (packet->count * 6);
if (pse_offset <= (packet->length + 1))
return packet->length + 1 - pse_offset;
/* This means that the packet is invalid! */
return 0;
}
/**
* gst_rtcp_packet_get_profile_specific_ext:
* @packet: a valid SR or RR #GstRTCPPacket
* @data: (out) (array length=len) (transfer none): result profile-specific data
* @len: (out): result length of the profile-specific data
*
* Returns: %TRUE if there was valid data.
*/
gboolean
gst_rtcp_packet_get_profile_specific_ext (GstRTCPPacket * packet,
guint8 ** data, guint * len)
{
guint16 pse_len;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
pse_len = gst_rtcp_packet_get_profile_specific_ext_length (packet);
if (pse_len > 0) {
if (len != NULL)
*len = pse_len * sizeof (guint32);
if (data != NULL) {
*data = packet->rtcp->map.data;
*data += packet->offset;
*data += ((packet->length + 1 - pse_len) * sizeof (guint32));
}
return TRUE;
}
return FALSE;
}
/**
* gst_rtcp_packet_copy_profile_specific_ext:
* @packet: a valid SR or RR #GstRTCPPacket
* @data: (out) (array length=len): result profile-specific data
* @len: (out): length of the profile-specific extension data
*
* The profile-specific extension data is copied into a new allocated
* memory area @data. This must be freed with g_free() after usage.
*
* Returns: %TRUE if there was valid data.
*/
gboolean
gst_rtcp_packet_copy_profile_specific_ext (GstRTCPPacket * packet,
guint8 ** data, guint * len)
{
guint16 pse_len;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RR ||
packet->type == GST_RTCP_TYPE_SR, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
pse_len = gst_rtcp_packet_get_profile_specific_ext_length (packet);
if (pse_len > 0) {
if (len != NULL)
*len = pse_len * sizeof (guint32);
if (data != NULL) {
guint8 *ptr = packet->rtcp->map.data + packet->offset;
ptr += ((packet->length + 1 - pse_len) * sizeof (guint32));
*data = g_memdup (ptr, pse_len * sizeof (guint32));
}
return TRUE;
}
return FALSE;
}
/**
* gst_rtcp_packet_sdes_get_item_count:
* @packet: a valid SDES #GstRTCPPacket
*
* Get the number of items in the SDES packet @packet.
*
* Returns: The number of items in @packet.
*/
guint
gst_rtcp_packet_sdes_get_item_count (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, 0);
return packet->count;
}
/**
* gst_rtcp_packet_sdes_first_item:
* @packet: a valid SDES #GstRTCPPacket
*
* Move to the first SDES item in @packet.
*
* Returns: TRUE if there was a first item.
*/
gboolean
gst_rtcp_packet_sdes_first_item (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
packet->item_offset = 4;
packet->item_count = 0;
packet->entry_offset = 4;
if (packet->count == 0)
return FALSE;
return TRUE;
}
/**
* gst_rtcp_packet_sdes_next_item:
* @packet: a valid SDES #GstRTCPPacket
*
* Move to the next SDES item in @packet.
*
* Returns: TRUE if there was a next item.
*/
gboolean
gst_rtcp_packet_sdes_next_item (GstRTCPPacket * packet)
{
guint8 *data;
guint offset;
guint len;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
/* if we are at the last item, we are done */
if (packet->item_count == packet->count)
return FALSE;
/* move to SDES */
data = packet->rtcp->map.data;
data += packet->offset;
/* move to item */
offset = packet->item_offset;
/* skip SSRC */
offset += 4;
/* don't overrun */
len = (packet->length << 2);
while (offset < len) {
if (data[offset] == 0) {
/* end of list, round to next 32-bit word */
offset = (offset + 4) & ~3;
break;
}
offset += data[offset + 1] + 2;
}
if (offset >= len)
return FALSE;
packet->item_offset = offset;
packet->item_count++;
packet->entry_offset = 4;
return TRUE;
}
/**
* gst_rtcp_packet_sdes_get_ssrc:
* @packet: a valid SDES #GstRTCPPacket
*
* Get the SSRC of the current SDES item.
*
* Returns: the SSRC of the current item.
*/
guint32
gst_rtcp_packet_sdes_get_ssrc (GstRTCPPacket * packet)
{
guint32 ssrc;
guint8 *data;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
/* move to SDES */
data = packet->rtcp->map.data;
data += packet->offset;
/* move to item */
data += packet->item_offset;
ssrc = GST_READ_UINT32_BE (data);
return ssrc;
}
/**
* gst_rtcp_packet_sdes_first_entry:
* @packet: a valid SDES #GstRTCPPacket
*
* Move to the first SDES entry in the current item.
*
* Returns: %TRUE if there was a first entry.
*/
gboolean
gst_rtcp_packet_sdes_first_entry (GstRTCPPacket * packet)
{
guint8 *data;
guint len, offset;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
/* move to SDES */
data = packet->rtcp->map.data;
data += packet->offset;
/* move to item */
offset = packet->item_offset;
/* skip SSRC */
offset += 4;
packet->entry_offset = 4;
/* don't overrun */
len = (packet->length << 2);
if (offset >= len)
return FALSE;
if (data[offset] == 0)
return FALSE;
return TRUE;
}
/**
* gst_rtcp_packet_sdes_next_entry:
* @packet: a valid SDES #GstRTCPPacket
*
* Move to the next SDES entry in the current item.
*
* Returns: %TRUE if there was a next entry.
*/
gboolean
gst_rtcp_packet_sdes_next_entry (GstRTCPPacket * packet)
{
guint8 *data;
guint len, offset, item_len;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
/* move to SDES */
data = packet->rtcp->map.data;
data += packet->offset;
/* move to item */
offset = packet->item_offset;
/* move to entry */
offset += packet->entry_offset;
item_len = data[offset + 1] + 2;
/* skip item */
offset += item_len;
/* don't overrun */
len = (packet->length << 2);
if (offset >= len)
return FALSE;
packet->entry_offset += item_len;
/* check for end of list */
if (data[offset] == 0)
return FALSE;
return TRUE;
}
/**
* gst_rtcp_packet_sdes_get_entry:
* @packet: a valid SDES #GstRTCPPacket
* @type: result of the entry type
* @len: (out): result length of the entry data
* @data: (out) (array length=len) (transfer none): result entry data
*
* Get the data of the current SDES item entry. @type (when not NULL) will
* contain the type of the entry. @data (when not NULL) will point to @len
* bytes.
*
* When @type refers to a text item, @data will point to a UTF8 string. Note
* that this UTF8 string is NOT null-terminated. Use
* gst_rtcp_packet_sdes_copy_entry() to get a null-terminated copy of the entry.
*
* Returns: %TRUE if there was valid data.
*/
gboolean
gst_rtcp_packet_sdes_get_entry (GstRTCPPacket * packet,
GstRTCPSDESType * type, guint8 * len, guint8 ** data)
{
guint8 *bdata;
guint offset;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
/* move to SDES */
bdata = packet->rtcp->map.data;
bdata += packet->offset;
/* move to item */
offset = packet->item_offset;
/* move to entry */
offset += packet->entry_offset;
if (bdata[offset] == 0)
return FALSE;
if (type)
*type = bdata[offset];
if (len)
*len = bdata[offset + 1];
if (data)
*data = &bdata[offset + 2];
return TRUE;
}
/**
* gst_rtcp_packet_sdes_copy_entry:
* @packet: a valid SDES #GstRTCPPacket
* @type: result of the entry type
* @len: (out): result length of the entry data
* @data: (out) (array length=len): result entry data
*
* This function is like gst_rtcp_packet_sdes_get_entry() but it returns a
* null-terminated copy of the data instead. use g_free() after usage.
*
* Returns: %TRUE if there was valid data.
*/
gboolean
gst_rtcp_packet_sdes_copy_entry (GstRTCPPacket * packet,
GstRTCPSDESType * type, guint8 * len, guint8 ** data)
{
guint8 *tdata;
guint8 tlen;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, FALSE);
if (!gst_rtcp_packet_sdes_get_entry (packet, type, &tlen, &tdata))
return FALSE;
if (len)
*len = tlen;
if (data)
*data = (guint8 *) g_strndup ((gchar *) tdata, tlen);
return TRUE;
}
/**
* gst_rtcp_packet_sdes_add_item:
* @packet: a valid SDES #GstRTCPPacket
* @ssrc: the SSRC of the new item to add
*
* Add a new SDES item for @ssrc to @packet.
*
* Returns: %TRUE if the item could be added, %FALSE if the maximum amount of
* items has been exceeded for the SDES packet or the MTU has been reached.
*/
gboolean
gst_rtcp_packet_sdes_add_item (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
guint offset;
gsize maxsize;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
/* increment item count when possible */
if (packet->count >= GST_RTCP_MAX_SDES_ITEM_COUNT)
goto no_space;
/* pretend there is a next packet for the next call */
packet->count++;
/* jump over current item */
gst_rtcp_packet_sdes_next_item (packet);
/* move to SDES */
data = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
data += packet->offset;
/* move to current item */
offset = packet->item_offset;
/* we need 2 free words now */
if (offset + 8 >= maxsize)
goto no_next;
/* write SSRC */
GST_WRITE_UINT32_BE (&data[offset], ssrc);
/* write 0 entry with padding */
GST_WRITE_UINT32_BE (&data[offset + 4], 0);
/* update count */
data[0] = (data[0] & 0xe0) | packet->count;
/* update length, we added 2 words */
packet->length += 2;
data[2] = (packet->length) >> 8;
data[3] = (packet->length) & 0xff;
packet->rtcp->map.size += 8;
return TRUE;
/* ERRORS */
no_space:
{
return FALSE;
}
no_next:
{
packet->count--;
return FALSE;
}
}
/**
* gst_rtcp_packet_sdes_add_entry:
* @packet: a valid SDES #GstRTCPPacket
* @type: the #GstRTCPSDESType of the SDES entry
* @len: the data length
* @data: (array length=len): the data
*
* Add a new SDES entry to the current item in @packet.
*
* Returns: %TRUE if the item could be added, %FALSE if the MTU has been
* reached.
*/
gboolean
gst_rtcp_packet_sdes_add_entry (GstRTCPPacket * packet, GstRTCPSDESType type,
guint8 len, const guint8 * data)
{
guint8 *bdata;
guint offset, padded;
gsize maxsize;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_SDES, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
/* move to SDES */
bdata = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
bdata += packet->offset;
/* move to item */
offset = packet->item_offset;
/* move to entry */
offset += packet->entry_offset;
/* add 1 byte end and up to 3 bytes padding to fill a full 32 bit word */
padded = (offset + 2 + len + 1 + 3) & ~3;
/* we need enough space for type, len, data and padding */
if (packet->offset + padded >= maxsize)
goto no_space;
packet->rtcp->map.size = packet->offset + padded;
bdata[offset] = type;
bdata[offset + 1] = len;
memcpy (&bdata[offset + 2], data, len);
bdata[offset + 2 + len] = 0;
/* calculate new packet length */
packet->length = (padded - 4) >> 2;
bdata[2] = (packet->length) >> 8;
bdata[3] = (packet->length) & 0xff;
/* position to new next entry */
packet->entry_offset += 2 + len;
return TRUE;
/* ERRORS */
no_space:
{
return FALSE;
}
}
/**
* gst_rtcp_packet_bye_get_ssrc_count:
* @packet: a valid BYE #GstRTCPPacket
*
* Get the number of SSRC fields in @packet.
*
* Returns: The number of SSRC fields in @packet.
*/
guint
gst_rtcp_packet_bye_get_ssrc_count (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, -1);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, -1);
return packet->count;
}
/**
* gst_rtcp_packet_bye_get_nth_ssrc:
* @packet: a valid BYE #GstRTCPPacket
* @nth: the nth SSRC to get
*
* Get the @nth SSRC of the BYE @packet.
*
* Returns: The @nth SSRC of @packet.
*/
guint32
gst_rtcp_packet_bye_get_nth_ssrc (GstRTCPPacket * packet, guint nth)
{
guint8 *data;
guint offset;
guint32 ssrc;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
g_return_val_if_fail (nth < packet->count, 0);
/* get offset in 32-bits words into packet, skip the header */
offset = 1 + nth;
/* check that we don't go past the packet length */
if (offset > packet->length)
return 0;
/* scale to bytes */
offset <<= 2;
offset += packet->offset;
/* check if the packet is valid */
if (offset + 4 > packet->rtcp->map.size)
return 0;
data = packet->rtcp->map.data;
data += offset;
ssrc = GST_READ_UINT32_BE (data);
return ssrc;
}
/**
* gst_rtcp_packet_bye_add_ssrc:
* @packet: a valid BYE #GstRTCPPacket
* @ssrc: an SSRC to add
*
* Add @ssrc to the BYE @packet.
*
* Returns: %TRUE if the ssrc was added. This function can return %FALSE if
* the max MTU is exceeded or the number of sources blocks is greater than
* #GST_RTCP_MAX_BYE_SSRC_COUNT.
*/
gboolean
gst_rtcp_packet_bye_add_ssrc (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
gsize maxsize;
guint offset;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
if (packet->count >= GST_RTCP_MAX_BYE_SSRC_COUNT)
goto no_space;
data = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
/* skip header */
offset = packet->offset + 4;
/* move to current index */
offset += (packet->count * 4);
if (offset + 4 >= maxsize)
goto no_space;
/* increment packet count and length */
packet->count++;
data[packet->offset]++;
packet->length += 1;
data[packet->offset + 2] = (packet->length) >> 8;
data[packet->offset + 3] = (packet->length) & 0xff;
packet->rtcp->map.size += 4;
/* move to new SSRC offset and write ssrc */
data += offset;
GST_WRITE_UINT32_BE (data, ssrc);
return TRUE;
/* ERRORS */
no_space:
{
return FALSE;
}
}
/**
* gst_rtcp_packet_bye_add_ssrcs:
* @packet: a valid BYE #GstRTCPPacket
* @ssrc: (array length=len) (transfer none): an array of SSRCs to add
* @len: number of elements in @ssrc
*
* Adds @len SSRCs in @ssrc to BYE @packet.
*
* Returns: %TRUE if the all the SSRCs were added. This function can return %FALSE if
* the max MTU is exceeded or the number of sources blocks is greater than
* #GST_RTCP_MAX_BYE_SSRC_COUNT.
*/
gboolean
gst_rtcp_packet_bye_add_ssrcs (GstRTCPPacket * packet, guint32 * ssrc,
guint len)
{
guint i;
gboolean res;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
res = TRUE;
for (i = 0; i < len && res; i++) {
res = gst_rtcp_packet_bye_add_ssrc (packet, ssrc[i]);
}
return res;
}
/* get the offset in packet of the reason length */
static guint
get_reason_offset (GstRTCPPacket * packet)
{
guint offset;
/* get amount of sources plus header */
offset = 1 + packet->count;
/* check that we don't go past the packet length */
if (offset > packet->length)
return 0;
/* scale to bytes */
offset <<= 2;
offset += packet->offset;
/* check if the packet is valid */
if (offset + 1 > packet->rtcp->map.size)
return 0;
return offset;
}
/**
* gst_rtcp_packet_bye_get_reason_len:
* @packet: a valid BYE #GstRTCPPacket
*
* Get the length of the reason string.
*
* Returns: The length of the reason string or 0 when there is no reason string
* present.
*/
guint8
gst_rtcp_packet_bye_get_reason_len (GstRTCPPacket * packet)
{
guint8 *data;
guint roffset;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
roffset = get_reason_offset (packet);
if (roffset == 0)
return 0;
data = packet->rtcp->map.data;
return data[roffset];
}
/**
* gst_rtcp_packet_bye_get_reason:
* @packet: a valid BYE #GstRTCPPacket
*
* Get the reason in @packet.
*
* Returns: The reason for the BYE @packet or NULL if the packet did not contain
* a reason string. The string must be freed with g_free() after usage.
*/
gchar *
gst_rtcp_packet_bye_get_reason (GstRTCPPacket * packet)
{
guint8 *data;
guint roffset;
guint8 len;
g_return_val_if_fail (packet != NULL, NULL);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, NULL);
g_return_val_if_fail (packet->rtcp != NULL, NULL);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, NULL);
roffset = get_reason_offset (packet);
if (roffset == 0)
return NULL;
data = packet->rtcp->map.data;
/* get length of reason string */
len = data[roffset];
if (len == 0)
return NULL;
/* move to string */
roffset += 1;
/* check if enough data to copy */
if (roffset + len > packet->rtcp->map.size)
return NULL;
return g_strndup ((gconstpointer) (data + roffset), len);
}
/**
* gst_rtcp_packet_bye_set_reason:
* @packet: a valid BYE #GstRTCPPacket
* @reason: a reason string
*
* Set the reason string to @reason in @packet.
*
* Returns: TRUE if the string could be set.
*/
gboolean
gst_rtcp_packet_bye_set_reason (GstRTCPPacket * packet, const gchar * reason)
{
guint8 *data;
guint roffset;
gsize maxsize;
guint8 len, padded;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_BYE, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
if (reason == NULL)
return TRUE;
len = strlen (reason);
if (len == 0)
return TRUE;
/* make room for the string before we get the offset */
packet->length++;
roffset = get_reason_offset (packet);
if (roffset == 0)
goto no_space;
data = packet->rtcp->map.data;
maxsize = packet->rtcp->map.maxsize;
/* we have 1 byte length and we need to pad to 4 bytes */
padded = ((len + 1) + 3) & ~3;
/* we need enough space for the padded length */
if (roffset + padded >= maxsize)
goto no_space;
data[roffset] = len;
memcpy (&data[roffset + 1], reason, len);
/* update packet length, we made room for 1 double word already */
packet->length += (padded >> 2) - 1;
data[packet->offset + 2] = (packet->length) >> 8;
data[packet->offset + 3] = (packet->length) & 0xff;
packet->rtcp->map.size += padded;
return TRUE;
/* ERRORS */
no_space:
{
packet->length--;
return FALSE;
}
}
/**
* gst_rtcp_packet_fb_get_sender_ssrc:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
*
* Get the sender SSRC field of the RTPFB or PSFB @packet.
*
* Returns: the sender SSRC.
*/
guint32
gst_rtcp_packet_fb_get_sender_ssrc (GstRTCPPacket * packet)
{
guint8 *data;
guint32 ssrc;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail ((packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB), 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
ssrc = GST_READ_UINT32_BE (data);
return ssrc;
}
/**
* gst_rtcp_packet_fb_set_sender_ssrc:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
* @ssrc: a sender SSRC
*
* Set the sender SSRC field of the RTPFB or PSFB @packet.
*/
void
gst_rtcp_packet_fb_set_sender_ssrc (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_READ);
data = packet->rtcp->map.data;
/* skip header */
data += packet->offset + 4;
GST_WRITE_UINT32_BE (data, ssrc);
}
/**
* gst_rtcp_packet_fb_get_media_ssrc:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
*
* Get the media SSRC field of the RTPFB or PSFB @packet.
*
* Returns: the media SSRC.
*/
guint32
gst_rtcp_packet_fb_get_media_ssrc (GstRTCPPacket * packet)
{
guint8 *data;
guint32 ssrc;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail ((packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB), 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data;
/* skip header and sender ssrc */
data += packet->offset + 8;
ssrc = GST_READ_UINT32_BE (data);
return ssrc;
}
/**
* gst_rtcp_packet_fb_set_media_ssrc:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
* @ssrc: a media SSRC
*
* Set the media SSRC field of the RTPFB or PSFB @packet.
*/
void
gst_rtcp_packet_fb_set_media_ssrc (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data;
/* skip header and sender ssrc */
data += packet->offset + 8;
GST_WRITE_UINT32_BE (data, ssrc);
}
/**
* gst_rtcp_packet_fb_get_type:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
*
* Get the feedback message type of the FB @packet.
*
* Returns: The feedback message type.
*/
GstRTCPFBType
gst_rtcp_packet_fb_get_type (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, GST_RTCP_FB_TYPE_INVALID);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB, GST_RTCP_FB_TYPE_INVALID);
return packet->count;
}
/**
* gst_rtcp_packet_fb_set_type:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
* @type: the #GstRTCPFBType to set
*
* Set the feedback message type of the FB @packet.
*/
void
gst_rtcp_packet_fb_set_type (GstRTCPPacket * packet, GstRTCPFBType type)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data;
data[packet->offset] = (data[packet->offset] & 0xe0) | type;
packet->count = type;
}
/**
* gst_rtcp_ntp_to_unix:
* @ntptime: an NTP timestamp
*
* Converts an NTP time to UNIX nanoseconds. @ntptime can typically be
* the NTP time of an SR RTCP message and contains, in the upper 32 bits, the
* number of seconds since 1900 and, in the lower 32 bits, the fractional
* seconds. The resulting value will be the number of nanoseconds since 1970.
*
* Returns: the UNIX time for @ntptime in nanoseconds.
*/
guint64
gst_rtcp_ntp_to_unix (guint64 ntptime)
{
guint64 unixtime;
/* conversion from NTP timestamp (seconds since 1900) to seconds since
* 1970. */
unixtime = ntptime - (G_GUINT64_CONSTANT (2208988800) << 32);
/* conversion to nanoseconds */
unixtime =
gst_util_uint64_scale (unixtime, GST_SECOND,
(G_GINT64_CONSTANT (1) << 32));
return unixtime;
}
/**
* gst_rtcp_unix_to_ntp:
* @unixtime: an UNIX timestamp in nanoseconds
*
* Converts a UNIX timestamp in nanoseconds to an NTP time. The caller should
* pass a value with nanoseconds since 1970. The NTP time will, in the upper
* 32 bits, contain the number of seconds since 1900 and, in the lower 32
* bits, the fractional seconds. The resulting value can be used as an ntptime
* for constructing SR RTCP packets.
*
* Returns: the NTP time for @unixtime.
*/
guint64
gst_rtcp_unix_to_ntp (guint64 unixtime)
{
guint64 ntptime;
/* convert clock time to NTP time. upper 32 bits should contain the seconds
* and the lower 32 bits, the fractions of a second. */
ntptime =
gst_util_uint64_scale (unixtime, (G_GINT64_CONSTANT (1) << 32),
GST_SECOND);
/* conversion from UNIX timestamp (seconds since 1970) to NTP (seconds
* since 1900). */
ntptime += (G_GUINT64_CONSTANT (2208988800) << 32);
return ntptime;
}
/**
* gst_rtcp_sdes_type_to_name:
* @type: a #GstRTCPSDESType
*
* Converts @type to the string equivalent. The string is typically used as a
* key in a #GstStructure containing SDES items.
*
* Returns: the string equivalent of @type
*/
const gchar *
gst_rtcp_sdes_type_to_name (GstRTCPSDESType type)
{
const gchar *result;
switch (type) {
case GST_RTCP_SDES_CNAME:
result = "cname";
break;
case GST_RTCP_SDES_NAME:
result = "name";
break;
case GST_RTCP_SDES_EMAIL:
result = "email";
break;
case GST_RTCP_SDES_PHONE:
result = "phone";
break;
case GST_RTCP_SDES_LOC:
result = "location";
break;
case GST_RTCP_SDES_TOOL:
result = "tool";
break;
case GST_RTCP_SDES_NOTE:
result = "note";
break;
case GST_RTCP_SDES_PRIV:
result = "priv";
break;
default:
result = NULL;
break;
}
return result;
}
/**
* gst_rtcp_sdes_name_to_type:
* @name: a SDES name
*
* Convert @name into a @GstRTCPSDESType. @name is typically a key in a
* #GstStructure containing SDES items.
*
* Returns: the #GstRTCPSDESType for @name or #GST_RTCP_SDES_PRIV when @name
* is a private sdes item.
*/
GstRTCPSDESType
gst_rtcp_sdes_name_to_type (const gchar * name)
{
if (name == NULL || strlen (name) == 0)
return GST_RTCP_SDES_INVALID;
if (strcmp ("cname", name) == 0)
return GST_RTCP_SDES_CNAME;
if (strcmp ("name", name) == 0)
return GST_RTCP_SDES_NAME;
if (strcmp ("email", name) == 0)
return GST_RTCP_SDES_EMAIL;
if (strcmp ("phone", name) == 0)
return GST_RTCP_SDES_PHONE;
if (strcmp ("location", name) == 0)
return GST_RTCP_SDES_LOC;
if (strcmp ("tool", name) == 0)
return GST_RTCP_SDES_TOOL;
if (strcmp ("note", name) == 0)
return GST_RTCP_SDES_NOTE;
return GST_RTCP_SDES_PRIV;
}
/**
* gst_rtcp_packet_fb_get_fci_length:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
*
* Get the length of the Feedback Control Information attached to a
* RTPFB or PSFB @packet.
*
* Returns: The length of the FCI in 32-bit words.
*/
guint16
gst_rtcp_packet_fb_get_fci_length (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data + packet->offset + 2;
return GST_READ_UINT16_BE (data) - 2;
}
/**
* gst_rtcp_packet_fb_set_fci_length:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
* @wordlen: Length of the FCI in 32-bit words
*
* Set the length of the Feedback Control Information attached to a
* RTPFB or PSFB @packet.
*
* Returns: %TRUE if there was enough space in the packet to add this much FCI
*/
gboolean
gst_rtcp_packet_fb_set_fci_length (GstRTCPPacket * packet, guint16 wordlen)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
if (packet->rtcp->map.maxsize < packet->offset + ((wordlen + 3) * 4))
return FALSE;
data = packet->rtcp->map.data + packet->offset + 2;
wordlen += 2;
GST_WRITE_UINT16_BE (data, wordlen);
packet->rtcp->map.size = packet->offset + ((wordlen + 1) * 4);
return TRUE;
}
/**
* gst_rtcp_packet_fb_get_fci:
* @packet: a valid RTPFB or PSFB #GstRTCPPacket
*
* Get the Feedback Control Information attached to a RTPFB or PSFB @packet.
*
* Returns: a pointer to the FCI
*/
guint8 *
gst_rtcp_packet_fb_get_fci (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, NULL);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_RTPFB ||
packet->type == GST_RTCP_TYPE_PSFB, NULL);
g_return_val_if_fail (packet->rtcp != NULL, NULL);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, NULL);
data = packet->rtcp->map.data + packet->offset;
if (GST_READ_UINT16_BE (data + 2) <= 2)
return NULL;
return data + 12;
}
/**
* gst_rtcp_packet_app_set_subtype:
* @packet: a valid APP #GstRTCPPacket
* @subtype: subtype of the packet
*
* Set the subtype field of the APP @packet.
*
* Since: 1.10
**/
void
gst_rtcp_packet_app_set_subtype (GstRTCPPacket * packet, guint8 subtype)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_APP);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data + packet->offset;
data[0] = (data[0] & 0xe0) | subtype;
}
/**
* gst_rtcp_packet_app_get_subtype:
* @packet: a valid APP #GstRTCPPacket
*
* Get the subtype field of the APP @packet.
*
* Returns: The subtype.
*
* Since: 1.10
*/
guint8
gst_rtcp_packet_app_get_subtype (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data + packet->offset;
return data[0] & 0x1f;
}
/**
* gst_rtcp_packet_app_set_ssrc:
* @packet: a valid APP #GstRTCPPacket
* @ssrc: SSRC/CSRC of the packet
*
* Set the SSRC/CSRC field of the APP @packet.
*
* Since: 1.10
*/
void
gst_rtcp_packet_app_set_ssrc (GstRTCPPacket * packet, guint32 ssrc)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_APP);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data + packet->offset + 4;
GST_WRITE_UINT32_BE (data, ssrc);
}
/**
* gst_rtcp_packet_app_get_ssrc:
* @packet: a valid APP #GstRTCPPacket
*
* Get the SSRC/CSRC field of the APP @packet.
*
* Returns: The SSRC/CSRC.
*
* Since: 1.10
*/
guint32
gst_rtcp_packet_app_get_ssrc (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data + packet->offset + 4;
return GST_READ_UINT32_BE (data);
}
/**
* gst_rtcp_packet_app_set_name:
* @packet: a valid APP #GstRTCPPacket
* @name: 4-byte ASCII name
*
* Set the name field of the APP @packet.
*
* Since: 1.10
*/
void
gst_rtcp_packet_app_set_name (GstRTCPPacket * packet, const gchar * name)
{
guint8 *data;
g_return_if_fail (packet != NULL);
g_return_if_fail (packet->type == GST_RTCP_TYPE_APP);
g_return_if_fail (packet->rtcp != NULL);
g_return_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE);
data = packet->rtcp->map.data + packet->offset + 8;
memcpy (data, name, 4);
}
/**
* gst_rtcp_packet_app_get_name:
* @packet: a valid APP #GstRTCPPacket
*
* Get the name field of the APP @packet.
*
* Returns: The 4-byte name field, not zero-terminated.
*
* Since: 1.10
*/
const gchar *
gst_rtcp_packet_app_get_name (GstRTCPPacket * packet)
{
g_return_val_if_fail (packet != NULL, NULL);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, NULL);
g_return_val_if_fail (packet->rtcp != NULL, NULL);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, NULL);
return (const gchar *) &packet->rtcp->map.data[packet->offset + 8];
}
/**
* gst_rtcp_packet_app_get_data_length:
* @packet: a valid APP #GstRTCPPacket
*
* Get the length of the application-dependent data attached to an APP
* @packet.
*
* Returns: The length of data in 32-bit words.
*
* Since: 1.10
*/
guint16
gst_rtcp_packet_app_get_data_length (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, 0);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, 0);
g_return_val_if_fail (packet->rtcp != NULL, 0);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, 0);
data = packet->rtcp->map.data + packet->offset + 2;
return GST_READ_UINT16_BE (data) - 2;
}
/**
* gst_rtcp_packet_app_set_data_length:
* @packet: a valid APP #GstRTCPPacket
* @wordlen: Length of the data in 32-bit words
*
* Set the length of the application-dependent data attached to an APP
* @packet.
*
* Returns: %TRUE if there was enough space in the packet to add this much
* data.
*
* Since: 1.10
*/
gboolean
gst_rtcp_packet_app_set_data_length (GstRTCPPacket * packet, guint16 wordlen)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, FALSE);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, FALSE);
g_return_val_if_fail (packet->rtcp != NULL, FALSE);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_WRITE, FALSE);
if (packet->rtcp->map.maxsize < packet->offset + ((wordlen + 3) * 4))
return FALSE;
data = packet->rtcp->map.data + packet->offset + 2;
wordlen += 2;
GST_WRITE_UINT16_BE (data, wordlen);
packet->rtcp->map.size = packet->offset + ((wordlen + 1) * 4);
return TRUE;
}
/**
* gst_rtcp_packet_app_get_data:
* @packet: a valid APP #GstRTCPPacket
*
* Get the application-dependent data attached to a RTPFB or PSFB @packet.
*
* Returns: A pointer to the data
*
* Since: 1.10
*/
guint8 *
gst_rtcp_packet_app_get_data (GstRTCPPacket * packet)
{
guint8 *data;
g_return_val_if_fail (packet != NULL, NULL);
g_return_val_if_fail (packet->type == GST_RTCP_TYPE_APP, NULL);
g_return_val_if_fail (packet->rtcp != NULL, NULL);
g_return_val_if_fail (packet->rtcp->map.flags & GST_MAP_READ, NULL);
data = packet->rtcp->map.data + packet->offset;
if (GST_READ_UINT16_BE (data + 2) <= 2)
return NULL;
return data + 12;
}