uvgrtp-base/include/rtcp.hh

323 lines
16 KiB
C++

#pragma once
#include <bitset>
#include <map>
#include <thread>
#include <vector>
#include "clock.hh"
#include "frame.hh"
#include "runner.hh"
#include "socket.hh"
#include "util.hh"
namespace uvg_rtp {
class connection;
enum ROLE {
RECEIVER,
SENDER
};
/* TODO: explain these constants */
const int RTP_SEQ_MOD = 1 << 16;
const int MIN_SEQUENTIAL = 2;
const int MAX_DROPOUT = 3000;
const int MAX_MISORDER = 100;
const int MIN_TIMEOUT = 5000;
struct rtcp_statistics {
/* receiver stats */
uint32_t received_pkts; /* Number of packets received */
uint32_t dropped_pkts; /* Number of dropped RTP packets */
uint32_t received_bytes; /* Number of bytes received excluding RTP Header */
/* sender stats */
uint32_t sent_pkts; /* Number of sent RTP packets */
uint32_t sent_bytes; /* Number of sent bytes excluding RTP Header */
uint32_t jitter; /* TODO: */
uint32_t transit; /* TODO: */
/* Receiver clock related stuff */
uint64_t initial_ntp; /* Wallclock reading when the first RTP packet was received */
uint32_t initial_rtp; /* RTP timestamp of the first RTP packet received */
uint32_t clock_rate; /* Rate of the clock (used for jitter calculations) */
uint32_t lsr; /* Middle 32 bits of the 64-bit NTP timestamp of previous SR */
uvg_rtp::clock::hrc::hrc_t sr_ts; /* When the last SR was received (used to calculate delay) */
uint16_t max_seq; /* Highest sequence number received */
uint16_t base_seq; /* First sequence number received */
uint16_t bad_seq; /* TODO: */
uint16_t cycles; /* Number of sequence cycles */
};
struct rtcp_participant {
uvg_rtp::socket *socket; /* socket associated with this participant */
sockaddr_in address; /* address of the participant */
struct rtcp_statistics stats; /* RTCP session statistics of the participant */
int probation; /* has the participant been fully accepted to the session */
int role; /* is the participant a sender or a receiver */
/* Save the latest RTCP packets received from this participant
* Users can query these packets using the SSRC of participant */
uvg_rtp::frame::rtcp_sender_frame *s_frame;
uvg_rtp::frame::rtcp_receiver_frame *r_frame;
uvg_rtp::frame::rtcp_sdes_frame *sdes_frame;
uvg_rtp::frame::rtcp_app_frame *app_frame;
};
class rtcp : public runner {
public:
rtcp(uint32_t ssrc, bool receiver);
rtcp(uvg_rtp::rtp *rtp);
~rtcp();
/* start the RTCP runner thread
*
* return RTP_OK on success and RTP_MEMORY_ERROR if the allocation fails */
rtp_error_t start();
/* End the RTCP session and send RTCP BYE to all participants
*
* return RTP_OK on success */
rtp_error_t stop();
/* Generate either RTCP Sender or Receiver report and sent it to all participants
* Return RTP_OK on success and RTP_ERROR on error */
rtp_error_t generate_report();
/* Handle different kinds of incoming packets
*
* These routines will convert the fields of "frame" from network to host byte order
*
* Currently nothing's done with valid packets, at some point an API for
* querying these reports is implemented
*
* Return RTP_OK on success and RTP_ERROR on error */
rtp_error_t handle_sender_report_packet(uvg_rtp::frame::rtcp_sender_frame *frame, size_t size);
rtp_error_t handle_receiver_report_packet(uvg_rtp::frame::rtcp_receiver_frame *frame, size_t size);
rtp_error_t handle_sdes_packet(uvg_rtp::frame::rtcp_sdes_frame *frame, size_t size);
rtp_error_t handle_bye_packet(uvg_rtp::frame::rtcp_bye_frame *frame, size_t size);
rtp_error_t handle_app_packet(uvg_rtp::frame::rtcp_app_frame *frame, size_t size);
/* Handle incoming RTCP packet (first make sure it's a valid RTCP packet)
* This function will call one of the above functions internally
*
* Return RTP_OK on success and RTP_ERROR on error */
rtp_error_t handle_incoming_packet(uint8_t *buffer, size_t size);
/* Send "frame" to all participants
*
* These routines will convert all necessary fields to network byte order
*
* Return RTP_OK on success
* Return RTP_INVALID_VALUE if "frame" is in some way invalid
* Return RTP_SEND_ERROR if sending "frame" did not succeed (see socket.hh for details) */
rtp_error_t send_sender_report_packet(uvg_rtp::frame::rtcp_sender_frame *frame);
rtp_error_t send_receiver_report_packet(uvg_rtp::frame::rtcp_receiver_frame *frame);
rtp_error_t send_sdes_packet(uvg_rtp::frame::rtcp_sdes_frame *frame);
rtp_error_t send_bye_packet(uvg_rtp::frame::rtcp_bye_frame *frame);
rtp_error_t send_app_packet(uvg_rtp::frame::rtcp_app_frame *frame);
/* Return the latest RTCP packet received from participant of "ssrc"
* Return nullptr if we haven't received this kind of packet or if "ssrc" doesn't exist
*
* NOTE: Caller is responsible for deallocating the memory */
uvg_rtp::frame::rtcp_sender_frame *get_sender_packet(uint32_t ssrc);
uvg_rtp::frame::rtcp_receiver_frame *get_receiver_packet(uint32_t ssrc);
uvg_rtp::frame::rtcp_sdes_frame *get_sdes_packet(uint32_t ssrc);
uvg_rtp::frame::rtcp_app_frame *get_app_packet(uint32_t ssrc);
/* create RTCP BYE packet using our own SSRC and send it to all participants */
rtp_error_t terminate_self();
/* Return a reference to vector that contains the sockets of all participants */
std::vector<uvg_rtp::socket>& get_sockets();
/* Somebody joined the multicast group the owner of this RTCP instance is part of
* Add it to RTCP participant list so we can start listening for reports
*
* "clock_rate" tells how much the RTP timestamp advances, this information is needed
* to calculate the interarrival jitter correctly. It has nothing do with our clock rate,
* (or whether we're even sending anything)
*
* Return RTP_OK on success and RTP_ERROR on error */
rtp_error_t add_participant(std::string dst_addr, uint16_t dst_port, uint16_t src_port, uint32_t clock_rate);
/* Functions for updating various RTP sender statistics */
void sender_inc_seq_cycle_count();
void sender_inc_sent_pkts(size_t n);
void sender_inc_sent_bytes(size_t n);
void sender_update_stats(uvg_rtp::frame::rtp_frame *frame);
void receiver_inc_sent_bytes(uint32_t sender_ssrc, size_t n);
void receiver_inc_overhead_bytes(uint32_t sender_ssrc, size_t n);
void receiver_inc_total_bytes(uint32_t sender_ssrc, size_t n);
void receiver_inc_sent_pkts(uint32_t sender_ssrc, size_t n);
/* Update the RTCP statistics regarding this packet
*
* Return RTP_OK if packet is valid
* Return RTP_INVALID_VALUE if SSRCs of remotes have collided or the packet is invalid in some way
* return RTP_SSRC_COLLISION if our own SSRC has collided and we need to reinitialize it */
rtp_error_t receiver_update_stats(uvg_rtp::frame::rtp_frame *frame);
/* If we've detected that our SSRC has collided with someone else's SSRC, we need to
* generate new random SSRC and reinitialize our own RTCP state.
* RTCP object still has the participants of "last session", we can use their SSRCs
* to detected new collision
*
* Return RTP_OK if reinitialization succeeded
* Return RTP_SSRC_COLLISION if our new SSRC has collided and we need to generate new SSRC */
rtp_error_t reset_rtcp_state(uint32_t ssrc);
/* Set wallclock reading for t = 0 and random RTP timestamp from where the counting is started
* + clock rate for calculating the correct increment */
void set_sender_ts_info(uint64_t clock_start, uint32_t clock_rate, uint32_t rtp_ts_start);
/* Update various session statistics */
void update_session_statistics(uvg_rtp::frame::rtp_frame *frame);
/* Return SSRCs of all participants */
std::vector<uint32_t> get_participants();
/* Alternate way to get RTCP packets is to install a hook for them. So instead of
* polling an RTCP packet, user can install a function that is called when
* a specific RTCP packet is received. */
rtp_error_t install_sender_hook(void (*hook)(uvg_rtp::frame::rtcp_sender_frame *));
rtp_error_t install_receiver_hook(void (*hook)(uvg_rtp::frame::rtcp_receiver_frame *));
rtp_error_t install_sdes_hook(void (*hook)(uvg_rtp::frame::rtcp_sdes_frame *));
rtp_error_t install_app_hook(void (*hook)(uvg_rtp::frame::rtcp_app_frame *));
/* Update RTCP-related session statistics */
static rtp_error_t packet_handler(void *arg, int flags, frame::rtp_frame **out);
private:
static void rtcp_runner(rtcp *rtcp);
/* when we start the RTCP instance, we don't know what the SSRC of the remote is
* when an RTP packet is received, we must check if we've already received a packet
* from this sender and if not, create new entry to receiver_stats_ map */
bool is_participant(uint32_t ssrc);
/* When we receive an RTP or RTCP packet, we need to check the source address and see if it's
* the same address where we've received packets before.
*
* If the address is new, it means we have detected an SSRC collision and the paket should
* be dropped We also need to check whether this SSRC matches with our own SSRC and if it does
* we need to send RTCP BYE and rejoin to the session */
bool collision_detected(uint32_t ssrc, sockaddr_in& src_addr);
/* Move participant from initial_peers_ to participants_ */
rtp_error_t add_participant(uint32_t ssrc);
/* We've got a message from new source (the SSRC of the frame is not known to us)
* Initialize statistics for the peer and move it to participants_ */
rtp_error_t init_new_participant(uvg_rtp::frame::rtp_frame *frame);
/* Initialize the RTP Sequence related stuff of peer
* This function assumes that the peer already exists in the participants_ map */
rtp_error_t init_participant_seq(uint32_t ssrc, uint16_t base_seq);
/* Update the SSRC's sequence related data in participants_ map
*
* Return RTP_OK if the received packet was OK
* Return RTP_GENERIC_ERROR if it wasn't and
* packet-related statistics should not be updated */
rtp_error_t update_participant_seq(uint32_t ssrc, uint16_t seq);
/* Update the RTCP bandwidth variables
*
* "pkt_size" tells how much rtcp_byte_count_
* should be increased before calculating the new average */
void update_rtcp_bandwidth(size_t pkt_size);
/* Functions for generating different kinds of reports.
* These functions will both generate the report and send it
*
* Return RTP_OK on success and RTP_ERROR on error */
rtp_error_t generate_sender_report();
rtp_error_t generate_receiver_report();
/* Because struct statistics contains uvgRTP clock object we cannot
* zero it out without compiler complaining about it so all the fields
* must be set to zero manually */
void zero_stats(uvg_rtp::rtcp_statistics *stats);
/* Pointer to RTP context from which clock rate etc. info is collected and which is
* used to change SSRC if a collision is detected */
uvg_rtp::rtp *rtp_;
/* are we a sender or a receiver */
int our_role_;
/* TODO: time_t?? */
size_t tp_; /* the last time an RTCP packet was transmitted */
size_t tc_; /* the current time */
size_t tn_; /* the next scheduled transmission time of an RTCP packet */
size_t pmembers_; /* the estimated number of session members at the time tn was last recomputed */
size_t members_; /* the most current estimate for the number of session members */
size_t senders_; /* the most current estimate for the number of senders in the session */
/* The target RTCP bandwidth, i.e., the total bandwidth
* that will be used for RTCP packets by all members of this session,
* in octets per second. This will be a specified fraction of the
* "session bandwidth" parameter supplied to the application at startup. */
size_t rtcp_bandwidth_;
/* Flag that is true if the application has sent data since
* the 2nd previous RTCP report was transmitted. */
bool we_sent_;
/* The average compound RTCP packet size, in octets,
* over all RTCP packets sent and received by this participant. The
* size includes lower-layer transport and network protocol headers
* (e.g., UDP and IP) as explained in Section 6.2 */
size_t avg_rtcp_pkt_pize_;
/* Number of RTCP packets and bytes sent and received by this participant */
size_t rtcp_pkt_count_;
size_t rtcp_byte_count_;
/* Flag that is true if the application has not yet sent an RTCP packet. */
bool initial_;
/* Copy of our own current SSRC */
uint32_t ssrc_;
/* NTP timestamp associated with initial RTP timestamp (aka t = 0) */
uint64_t clock_start_;
/* Clock rate of the media ie. how fast does the time increase */
uint32_t clock_rate_;
/* The first value of RTP timestamp (aka t = 0) */
uint32_t rtp_ts_start_;
std::map<uint32_t, rtcp_participant *> participants_;
size_t num_receivers_;
/* statistics for RTCP Sender and Receiver Reports */
struct rtcp_statistics our_stats;
/* If we expect frames from remote but haven't received anything from remote yet,
* the participant resides in this vector until he's moved to participants_ */
std::vector<rtcp_participant *> initial_participants_;
/* Vector of sockets the RTCP runner is listening to
*
* The socket are also stored here (in addition to participants_ map) so they're easier
* to pass to poll when RTCP runner is listening to incoming packets */
std::vector<uvg_rtp::socket> sockets_;
void (*sender_hook_)(uvg_rtp::frame::rtcp_sender_frame *);
void (*receiver_hook_)(uvg_rtp::frame::rtcp_receiver_frame *);
void (*sdes_hook_)(uvg_rtp::frame::rtcp_sdes_frame *);
void (*app_hook_)(uvg_rtp::frame::rtcp_app_frame *);
};
};