ccRTP 2.1.2
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Data Structures | Public Member Functions | Protected Member Functions | Protected Attributes | Private Attributes
RTPPacket Class Reference

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

#include <rtppkt.h>

Inheritance diagram for RTPPacket:
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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 RFC2833PayloadgetRaw2833Payload (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...
 
RTPFixedHeadergetHeader () const
 Return low level structure for the header of the packet. More...
 
void setExtension (bool e)
 
const RTPHeaderExtgetHeaderExt () 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 72 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
blockwhole packet
lentotal length (header + payload + padding) of the packet
duplicatewhether to memcopy the packet. At present, this feature is not used.
Note
used in IncomingRTPPkt.

Definition at line 109 of file rtppkt.cpp.

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
hdrlenlength of the header (including CSRC and extension).
plenpayload length.
paddinglenpad packet to a multiple of paddinglen
Note
used in OutgoingRTPPkt.

Definition at line 132 of file rtppkt.cpp.

virtual RTPPacket::~RTPPacket ( )
inlineprotectedvirtual

Destructor, free the buffer provided in the constructor.

Definition at line 306 of file rtppkt.h.

Member Function Documentation

void RTPPacket::endPacket ( )
protected

Free memory allocated for the packet.

Definition at line 167 of file rtppkt.cpp.

uint16 RTPPacket::get2833Duration ( void  )
inline

Fetch 2833 duration field.

Returns
2833 duration in native host machine byte order.

Definition at line 485 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 212 of file rtppkt.h.

uint16 RTPPacket::getCSRCsCount ( ) const
inline

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

Definition at line 201 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 255 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 243 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 228 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 321 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 336 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 114 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 174 of file rtppkt.h.

const uint8* const RTPPacket::getPayload ( ) const
inline
Returns
pointer to the payload section of the packet.

Definition at line 121 of file rtppkt.h.

uint32 RTPPacket::getPayloadSize ( ) const
inline
Returns
length of the payload section, in octets.

Definition at line 128 of file rtppkt.h.

PayloadType RTPPacket::getPayloadType ( ) const
inline
Returns
value of the PT header field.

Definition at line 135 of file rtppkt.h.

uint8 RTPPacket::getProtocolVersion ( ) const
inline
Returns
RTP protocol version of packet.

Definition at line 156 of file rtppkt.h.

struct RFC2833Payload* RTPPacket::getRaw2833Payload ( void  )
inline

Fetch a raw 2833 packet.

Returns
low level 2833 data structure.

Definition at line 477 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 268 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 278 of file rtppkt.h.

uint32 RTPPacket::getRawPacketSizeSrtp ( ) const
inline

Definition at line 282 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 348 of file rtppkt.h.

uint16 RTPPacket::getSeqNum ( ) const
inline
Returns
value of the sequence number header field, in host order.

Definition at line 142 of file rtppkt.h.

size_t RTPPacket::getSizeOfFixedHeader ( ) const
inline

Definition at line 286 of file rtppkt.h.

uint32 RTPPacket::getTimestamp ( ) const
inline
Returns
packet timestamp in host order.

Definition at line 149 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 193 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 184 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 164 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
paddingIf true then set padding flag in RTP header and re-compute payloadSize.

Definition at line 178 of file rtppkt.cpp.

void RTPPacket::set2833Duration ( uint16  timestamp)
inline

Set 2833 duration field.

Parameters
timestampto use, native host machine byte order.

Definition at line 493 of file rtppkt.h.

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

Definition at line 352 of file rtppkt.h.

void RTPPacket::setExtension ( bool  e)
inlineprotected

Definition at line 325 of file rtppkt.h.

Field Documentation

unsigned char* RTPPacket::buffer
private

packet in memory

Definition at line 383 of file rtppkt.h.

uint16 RTPPacket::cachedSeqNum
protected

Packet sequence number in host order.

Definition at line 356 of file rtppkt.h.

uint32 RTPPacket::cachedTimestamp
protected

Packet timestamp in host order (includes initial shift).

Definition at line 358 of file rtppkt.h.

bool RTPPacket::duplicated
private

whether the object was contructed with duplicated = true

Definition at line 387 of file rtppkt.h.

uint32 RTPPacket::hdrSize
private

size of the header, including contributing sources and extensions

Definition at line 385 of file rtppkt.h.

uint32 RTPPacket::payloadSize
protected

note: payload (not full packet) size.

Definition at line 379 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 366 of file rtppkt.h.

int32 RTPPacket::srtpLength
protected

Lebgth of additional SRTP data.

Covers the SRTP authentication and MKI data.

Definition at line 373 of file rtppkt.h.

uint32 RTPPacket::total
protected

total length, including header, payload and padding

Definition at line 376 of file rtppkt.h.


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