net_tpipe.h

// Copyright 2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
// "Tpipe" protocol for reliable byte-streams over UDP or Ethernet.
 
#pragma once
 
#include <satcat5/eth_address.h>
#include <satcat5/io_buffer.h>
#include <satcat5/net_core.h>
#include <satcat5/polling.h>
#include <satcat5/timeref.h>
#include <satcat5/udp_core.h>
 
namespace satcat5 {
    namespace net {
        class Tpipe
            : public satcat5::io::BufferedIO
            , public satcat5::net::Protocol
            , protected satcat5::poll::Timer
        {
        public:
            void close();
 
            bool completed() const;
 
            inline void set_retransmit(u16 msec) {m_retransmit = msec;}
 
            inline void set_timeout(u16 msec) {m_timeout = msec;}
 
            void set_txonly();
 
        protected:
            explicit Tpipe(satcat5::net::Address* dst);
            ~Tpipe() SATCAT5_OPTIONAL_DTOR;
 
            // Internal event callbacks.
            void data_rcvd(satcat5::io::Readable* src) override;
            void frame_rcvd(satcat5::io::LimitedRead& src) override;
            void timer_event() override;
 
            void send_block();
 
            void send_start();
 
            static constexpr unsigned MAX_WINDOW = 512;
 
            // Other protocol constants:
            static constexpr u16
                FLAG_START      = 0x8000,   
                FLAG_STOP       = 0x4000,   
                FLAG_LEN        = 0x03FF,   
                STATE_OPENREQ   = 0x0001,   
                STATE_READY     = 0x0002,   
                STATE_TXBUSY    = 0x0004,   
                STATE_CLOSING   = 0x0008,   
                STATE_TXONLY    = 0x0010;   
 
            // Protocol state.
            satcat5::net::Address* const m_iface; 
            u16 m_retry;                    
            u16 m_state;                    
            u16 m_retransmit;               
            u16 m_timeout;                  
            u16 m_txpos;                    
            u16 m_txref;                    
            u16 m_rxpos;                    
            u16 m_rxref;                    
            u8 m_txbuff[MAX_WINDOW];        
            u8 m_rxbuff[MAX_WINDOW];        
        };
    }
 
    // Wrappers for commonly used network interfaces:
    namespace eth {
        class Tpipe final
            : protected satcat5::eth::AddressContainer
            , public satcat5::net::Tpipe
        {
        public:
            explicit Tpipe(satcat5::eth::Dispatch* iface);
 
            void bind(
                const satcat5::eth::MacType& etype,
                const satcat5::eth::VlanTag& vtag = satcat5::eth::VTAG_NONE);
 
            void connect(
                const satcat5::eth::MacAddr& addr,
                const satcat5::eth::MacType& etype,
                const satcat5::eth::VlanTag& vtag = satcat5::eth::VTAG_NONE);
 
            inline bool ready() const {return m_addr.ready();}
        };
    }
 
    namespace udp {
        class Tpipe final
            : protected satcat5::udp::AddressContainer
            , public satcat5::net::Tpipe
        {
        public:
            explicit Tpipe(satcat5::udp::Dispatch* iface);
 
            void bind(const satcat5::udp::Port& port);
 
            void connect(
                const satcat5::ip::Addr& addr,
                const satcat5::udp::Port& port,
                const satcat5::eth::VlanTag& vtag = satcat5::eth::VTAG_NONE);
 
            inline bool ready() const {return m_addr.ready();}
        };
    }
}