uvgrtp-base/include/uvgrtp/frame.hh

#pragma once

#include "util.hh"

#ifdef _WIN32
#include <winsock2.h>
#include <windows.h>
#include <ws2def.h>
#else
#include <netinet/in.h>
#endif

#include <string>
#include <vector>

namespace uvgrtp {
    namespace frame {

        enum RTCP_FRAME_TYPE {
            RTCP_FT_SR   = 200, /* Sender report */
            RTCP_FT_RR   = 201, /* Receiver report */
            RTCP_FT_SDES = 202, /* Source description */
            RTCP_FT_BYE  = 203, /* Goodbye */
            RTCP_FT_APP  = 204  /* Application-specific message */
        };

        PACK(struct rtp_header {
            uint8_t version:2;
            uint8_t padding:1;
            uint8_t ext:1;
            uint8_t cc:4;
            uint8_t marker:1;
            uint8_t payload:7;
            uint16_t seq = 0;
            uint32_t timestamp = 0;
            uint32_t ssrc = 0;
        });

        PACK(struct ext_header {
            uint16_t type = 0;
            uint16_t len = 0;
            uint8_t *data = nullptr;
        });

        struct rtp_frame {
            struct rtp_header header;
            uint32_t *csrc = nullptr;
            struct ext_header *ext = nullptr;

            size_t padding_len = 0; /* non-zero if frame is padded */
            size_t payload_len = 0; /* payload_len: total_len - header_len - padding length (if padded) */

            /* Probation zone is a small area of free-to-use memory for the frame receiver
             * when handling fragments. For example HEVC fragments that belong to future frames
             * but cannot be relocated there (start sequence missing) are copied to probation
             * zone and when the frame becomes active, all fragments in the probation are relocated
             *
             * NOTE 1: Probation zone will increase the memory usage and will increase
             * the internal fragmentation as this memory is not usable for anything else
             *
             * NOTE 2: This is a Linux-only optimization */
            size_t probation_len = 0;
            size_t probation_off = 0;
            uint8_t *probation = nullptr;
            uint8_t *payload = nullptr;

            uint8_t *dgram = nullptr;      /* pointer to the UDP datagram (for internal use only) */
            size_t   dgram_size = 0; /* size of the UDP datagram */

            rtp_format_t format = RTP_FORMAT_GENERIC;
            int  type = 0;
            sockaddr_in src_addr = {};
        };

        struct rtcp_header {
            uint8_t version = 0;
            uint8_t padding = 0;
            union {
                uint8_t count = 0;
                uint8_t pkt_subtype; /* for app packets */
            };
            uint8_t pkt_type = 0;
            uint16_t length = 0; // whole message measured in 32-bit words
        };

        struct rtcp_sender_info {
            uint32_t ntp_msw = 0; /* NTP timestamp, most significant word */
            uint32_t ntp_lsw = 0; /* NTP timestamp, least significant word */
            uint32_t rtp_ts = 0;  /* RTP timestamp corresponding to same time as NTP */
            uint32_t pkt_cnt = 0;
            uint32_t byte_cnt = 0;
        };

        struct rtcp_report_block {
            uint32_t ssrc = 0;
            uint8_t  fraction = 0;
            int32_t  lost = 0;
            uint32_t last_seq = 0;
            uint32_t jitter = 0;
            uint32_t lsr = 0;  /* last Sender Report */
            uint32_t dlsr = 0; /* delay since last Sender Report */
        };

        struct rtcp_receiver_report {
            struct rtcp_header header;
            uint32_t ssrc = 0;
            std::vector<rtcp_report_block> report_blocks;
        };

        struct rtcp_sender_report {
            struct rtcp_header header;
            uint32_t ssrc = 0;
            struct rtcp_sender_info sender_info;
            std::vector<rtcp_report_block> report_blocks;
        };

        struct rtcp_sdes_item {
            uint8_t type = 0;
            uint8_t length = 0;
            uint8_t *data = nullptr;
        };

        struct rtcp_sdes_chunk {
            uint32_t ssrc = 0;
            std::vector<rtcp_sdes_item> items;
        };

        struct rtcp_sdes_packet {
            struct rtcp_header header;
            std::vector<rtcp_sdes_chunk> chunks;
        };

        struct rtcp_app_packet {
            struct rtcp_header header;
            uint32_t ssrc = 0;
            uint8_t name[4] = {0};
            uint8_t *payload = nullptr;
            size_t payload_len = 0; // in bytes
        };

        PACK(struct zrtp_frame {
            uint8_t version:4;
            uint16_t unused:12;
            uint16_t seq = 0;
            uint32_t magic = 0;
            uint32_t ssrc = 0;
            uint8_t payload[1];
        });

        /* Allocate an RTP frame
         *
         * First function allocates an empty RTP frame (no payload)
         *
         * Second allocates an RTP frame with payload of size "payload_len",
         *
         * Third allocate an RTP frame with payload of size "payload_len"
         * + probation zone of size "pz_size" * MAX_PAYLOAD
         *
         * Return pointer to frame on success
         * Return nullptr on error and set rtp_errno to:
         *    RTP_MEMORY_ERROR if allocation of memory failed */
        rtp_frame *alloc_rtp_frame();
        rtp_frame *alloc_rtp_frame(size_t payload_len);
        rtp_frame *alloc_rtp_frame(size_t payload_len, size_t pz_size);


        /* Deallocate RTP frame
         *
         * Return RTP_OK on successs
         * Return RTP_INVALID_VALUE if "frame" is nullptr */
        rtp_error_t dealloc_frame(uvgrtp::frame::rtp_frame *frame);


        /* Allocate ZRTP frame
         * Parameter "payload_size" defines the length of the frame
         *
         * Return pointer to frame on success
         * Return nullptr on error and set rtp_errno to:
         *    RTP_MEMORY_ERROR if allocation of memory failed
         *    RTP_INVALID_VALUE if "payload_size" is 0 */
        void* alloc_zrtp_frame(size_t payload_size);


        /* Deallocate ZRTP frame
         *
         * Return RTP_OK on successs
         * Return RTP_INVALID_VALUE if "frame" is nullptr */
        rtp_error_t dealloc_frame(uvgrtp::frame::zrtp_frame* frame);
    }
}

namespace uvg_rtp = uvgrtp;