A base class for both IncomingRTPPkt and OutgoingRTPPkt. More...

#include <rtppkt.h>

Inheritance diagram for RTPPacket:

Collaboration diagram for RTPPacket:

Data Structures
struct	RFC2833Payload
	a structure defining RFC2833 Telephony events. More...

struct	RTPFixedHeader
	RTP fixed header as it is send through the network. More...

struct	RTPHeaderExt
	Fixed component of the variable-length header extension, appended to the fixed header, after the CSRC list, when X == 1. More...

Public Member Functions
	RTPPacket (const unsigned char *const block, size_t len, bool duplicate=false)
	Constructor, construct a packet object given the memory zone its content (header and payload) is stored. More...

	RTPPacket (size_t hdrlen, size_t plen, uint8 paddinglen, CryptoContext *pcc=NULL)
	Construct a packet object without specifying its real content yet. More...

uint32	getHeaderSize () const
	Get the length of the header, including contributing sources identifiers and header extension, if present. More...

const uint8 *const	getPayload () const

uint32	getPayloadSize () const

PayloadType	getPayloadType () const

uint16	getSeqNum () const

uint32	getTimestamp () const

uint8	getProtocolVersion () const

bool	isPadded () const
	Ask whether the packet contains padding bytes at the end. More...

uint8	getPaddingSize () const
	Get the number of octets padding the end of the payload section. More...

bool	isMarked () const
	Ask whether the packet is marked (for isntance, is a new talk spurt in some audio profiles). More...

bool	isExtended () const
	Ask whether the packet contains header extensions. More...

uint16	getCSRCsCount () const
	Get the number of contributing sources specified in the packet header. More...

const uint32 *	getCSRCs () const
	Get the 32-bit identifiers of the contributing sources for the packet as an array, of length getCSRCsCount(). More...

uint16	getHdrExtUndefined () const
	Get the first 16 bits (in network order) of the header of the RTP header extension. More...

uint32	getHdrExtSize () const
	Get the length (in octets) of the data contained in the header extension. More...

const unsigned char *	getHdrExtContent () const
	Get the content of the header extension. More...

const unsigned char *const	getRawPacket () const
	Get the raw packet as it will be sent through the network. More...

uint32	getRawPacketSize () const
	Get the raw packet length, including header, extension, payload and padding. More...

uint32	getRawPacketSizeSrtp () const

size_t	getSizeOfFixedHeader () const

void	reComputePayLength (bool padding)
	Re-compute payload length. More...

struct RFC2833Payload *	getRaw2833Payload (void)
	Fetch a raw 2833 packet. More...

uint16	get2833Duration (void)
	Fetch 2833 duration field. More...

void	set2833Duration (uint16 timestamp)
	Set 2833 duration field. More...

Protected Member Functions
virtual	~RTPPacket ()
	Destructor, free the buffer provided in the constructor. More...

void	endPacket ()
	Free memory allocated for the packet. More...

RTPFixedHeader *	getHeader () const
	Return low level structure for the header of the packet. More...

void	setExtension (bool e)

const RTPHeaderExt *	getHeaderExt () const
	Get a pointer to RTPHeaderExt pointing after the RTP header (fixed part plus contributing sources). More...

uint32	getRawTimestamp () const
	Obtain the absolute timestamp carried in the packet header. More...

void	setbuffer (const void *src, size_t len, size_t pos)

Protected Attributes
uint16	cachedSeqNum
	Packet sequence number in host order. More...

uint32	cachedTimestamp
	Packet timestamp in host order (includes initial shift). More...

uint32	srtpDataOffset
	Offset into packet memory pointing to area for SRTP data. More...

int32	srtpLength
	Lebgth of additional SRTP data. More...

uint32	total
	total length, including header, payload and padding More...

uint32	payloadSize
	note: payload (not full packet) size. More...

Private Attributes
unsigned char *	buffer
	packet in memory More...

uint32	hdrSize
	size of the header, including contributing sources and extensions More...

bool	duplicated
	whether the object was contructed with duplicated = true More...

Detailed Description

A base class for both IncomingRTPPkt and OutgoingRTPPkt.

Provides common low level header structures and related methods. This class provides an interface that allows for partial and generic manipulation of RTP data packets. Values are returned in host order, except raw structures, which are returned as they are sent through the network.

Author: David Sugar dyfet.nosp@m.@ost.nosp@m.el.co.nosp@m.m

Definition at line 75 of file rtppkt.h.

Constructor & Destructor Documentation

RTPPacket::RTPPacket	(	const unsigned char *const	block,
		size_t	len,
		bool	duplicate = `false`
	)

Constructor, construct a packet object given the memory zone its content (header and payload) is stored.

Commonly used to build RTPPacket objects from incoming data.

Parameters

block	whole packet
len	total length (header + payload + padding) of the packet
duplicate	whether to memcopy the packet. At present, this feature is not used.

Note: used in IncomingRTPPkt.

RTPPacket::RTPPacket	(	size_t	hdrlen,
		size_t	plen,
		uint8	paddinglen,
		CryptoContext *	pcc = `NULL`
	)

Construct a packet object without specifying its real content yet.

Commonly used for outgoing packets. Header fields and payload must be filled in by another methods or by a derived constructor.

Parameters

hdrlen	length of the header (including CSRC and extension).
plen	payload length.
paddinglen	pad packet to a multiple of paddinglen

Note: used in OutgoingRTPPkt.

virtual RTPPacket::~RTPPacket ( )

inlineprotectedvirtual

Destructor, free the buffer provided in the constructor.

Definition at line 309 of file rtppkt.h.

Member Function Documentation

void RTPPacket::endPacket ( )

protected

Free memory allocated for the packet.

uint16 RTPPacket::get2833Duration ( void )

inline

Fetch 2833 duration field.

Returns: 2833 duration in native host machine byte order.

Definition at line 488 of file rtppkt.h.

const uint32* RTPPacket::getCSRCs ( ) const

inline

Get the 32-bit identifiers of the contributing sources for the packet as an array, of length getCSRCsCount().

Returns: An array of CSRC identifiers as they are in the packet (in network order).

Definition at line 215 of file rtppkt.h.

uint16 RTPPacket::getCSRCsCount ( ) const

inline

Get the number of contributing sources specified in the packet header.

Definition at line 204 of file rtppkt.h.

const unsigned char* RTPPacket::getHdrExtContent ( ) const

inline

Get the content of the header extension.

Returns: NULL if the packet has no header extension, otherwise a pointer to the packet header extension content.

Definition at line 258 of file rtppkt.h.

uint32 RTPPacket::getHdrExtSize ( ) const

inline

Get the length (in octets) of the data contained in the header extension.

Note that this length does not include the four octets at the beginning of the header extension.

Returns: 0 if the packet has no header extension, otherwise the length.

Note: 0 is a valid value for this field, so RTPPacket::isExtended() should be used.

Definition at line 246 of file rtppkt.h.

uint16 RTPPacket::getHdrExtUndefined ( ) const

inline

Get the first 16 bits (in network order) of the header of the RTP header extension.

Its meaning is undefined at this level.

Returns: 0 if the packet has no header extension, otherwise the first 16 bits of the header extension, in network order.

Note: 0 could be a valid value for the first 16 bits, in that case RTPPacket::isExtended() should be use.

Definition at line 231 of file rtppkt.h.

RTPFixedHeader* RTPPacket::getHeader ( ) const

inlineprotected

Return low level structure for the header of the packet.

Returns: RTPFixedHeader pointer to the header of the packet.

Definition at line 324 of file rtppkt.h.

const RTPHeaderExt* RTPPacket::getHeaderExt ( ) const

inlineprotected

Get a pointer to RTPHeaderExt pointing after the RTP header (fixed part plus contributing sources).

No check for for the X bit is done.

Returns: header extension if present, garbage if not.

Definition at line 339 of file rtppkt.h.

uint32 RTPPacket::getHeaderSize ( ) const

inline

Get the length of the header, including contributing sources identifiers and header extension, if present.

Returns: number of octets.

Definition at line 117 of file rtppkt.h.

uint8 RTPPacket::getPaddingSize ( ) const

inline

Get the number of octets padding the end of the payload section.

Returns: Padding length in octets.

Definition at line 177 of file rtppkt.h.

const uint8* const RTPPacket::getPayload ( ) const

inline

Returns: pointer to the payload section of the packet.

Definition at line 124 of file rtppkt.h.

uint32 RTPPacket::getPayloadSize ( ) const

inline

Returns: length of the payload section, in octets.

Definition at line 131 of file rtppkt.h.

PayloadType RTPPacket::getPayloadType ( ) const

inline

Returns: value of the PT header field.

Definition at line 138 of file rtppkt.h.

uint8 RTPPacket::getProtocolVersion ( ) const

inline

Returns: RTP protocol version of packet.

Definition at line 159 of file rtppkt.h.

struct RFC2833Payload* RTPPacket::getRaw2833Payload ( void )

inline

Fetch a raw 2833 packet.

Returns: low level 2833 data structure.

Definition at line 480 of file rtppkt.h.

const unsigned char* const RTPPacket::getRawPacket ( ) const

inline

Get the raw packet as it will be sent through the network.

Returns: memory zone where the raw packet structure is stored in.

Definition at line 271 of file rtppkt.h.

uint32 RTPPacket::getRawPacketSize ( ) const

inline

Get the raw packet length, including header, extension, payload and padding.

Returns: size of the raw packet structure.

Definition at line 281 of file rtppkt.h.

uint32 RTPPacket::getRawPacketSizeSrtp ( ) const

inline

Definition at line 285 of file rtppkt.h.

uint32 RTPPacket::getRawTimestamp ( ) const

inlineprotected

Obtain the absolute timestamp carried in the packet header.

Returns: 32-bit timestamp in host order.

Definition at line 351 of file rtppkt.h.

uint16 RTPPacket::getSeqNum ( ) const

inline

Returns: value of the sequence number header field, in host order.

Definition at line 145 of file rtppkt.h.

size_t RTPPacket::getSizeOfFixedHeader ( ) const

inline

Definition at line 289 of file rtppkt.h.

uint32 RTPPacket::getTimestamp ( ) const

inline

Returns: packet timestamp in host order.

Definition at line 152 of file rtppkt.h.

bool RTPPacket::isExtended ( ) const

inline

Ask whether the packet contains header extensions.

Returns: true if the header extension bit is 1.

Definition at line 196 of file rtppkt.h.

bool RTPPacket::isMarked ( ) const

inline

Ask whether the packet is marked (for isntance, is a new talk spurt in some audio profiles).

Returns: true is the header marker bit is 1.

Definition at line 187 of file rtppkt.h.

bool RTPPacket::isPadded ( ) const

inline

Ask whether the packet contains padding bytes at the end.

Returns: true if the header padding bit is 1.

Definition at line 167 of file rtppkt.h.

void RTPPacket::reComputePayLength ( bool padding )

Re-compute payload length.

This recomputation may be necessary in case of SRTP. We need to decrypt the packet before we can handle padding. See takeInDataPacket in incqueue.cpp

Parameters

padding If true then set padding flag in RTP header and re-compute payloadSize.

void RTPPacket::set2833Duration ( uint16 timestamp )

inline

Set 2833 duration field.

Parameters

timestamp to use, native host machine byte order.

Definition at line 496 of file rtppkt.h.

void RTPPacket::setbuffer	(	const void *	src,
		size_t	len,
		size_t	pos
	)

inlineprotected

Definition at line 355 of file rtppkt.h.

void RTPPacket::setExtension ( bool e )

inlineprotected

Definition at line 328 of file rtppkt.h.

Field Documentation

unsigned char* RTPPacket::buffer

private

packet in memory

Definition at line 386 of file rtppkt.h.

uint16 RTPPacket::cachedSeqNum

protected

Packet sequence number in host order.

Definition at line 359 of file rtppkt.h.

uint32 RTPPacket::cachedTimestamp

protected

Packet timestamp in host order (includes initial shift).

Definition at line 361 of file rtppkt.h.

bool RTPPacket::duplicated

private

whether the object was contructed with duplicated = true

Definition at line 390 of file rtppkt.h.

uint32 RTPPacket::hdrSize

private

size of the header, including contributing sources and extensions

Definition at line 388 of file rtppkt.h.

uint32 RTPPacket::payloadSize

protected

note: payload (not full packet) size.

Definition at line 382 of file rtppkt.h.

uint32 RTPPacket::srtpDataOffset

protected

Offset into packet memory pointing to area for SRTP data.

This offset points to the memory where the SRTP protect will store the authentication and MKI data.

Definition at line 369 of file rtppkt.h.

int32 RTPPacket::srtpLength

protected

Lebgth of additional SRTP data.

Covers the SRTP authentication and MKI data.

Definition at line 376 of file rtppkt.h.

uint32 RTPPacket::total

protected

total length, including header, payload and padding

Definition at line 379 of file rtppkt.h.

The documentation for this class was generated from the following file:

rtppkt.h

Data Structures

Public Member Functions

Protected Member Functions

Protected Attributes

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation