common.h File Reference

Layer 4 (Transport) - the connection state every half of TCP reads. More...

#include "config/platform/platform.h"
#include "memoria_anularis/memoria_anularis.h"
#include "network_drivers/transport/tcp/evt/evt.h"
#include "shared/ip/ip.h"
#include <stdatomic.h>
#include "protocore_config.h"

Go to the source code of this file.

Classes
struct	TcpConn
	A single TCP connection context. More...
struct	Listener
	State for one TCP listening port. More...

Macros
#define	PROTOCORE_PROTO_SLOT_NONE   0xFFu
	Sentinel for TcpConn.proto_slot meaning "no per-protocol session bound".
#define	PROTOCORE_DSCP_UNSET   0xFF
	The row carries no code point of its own; accept() takes the server-wide default.

Typedefs
typedef PROTOCORE_BEGIN_DECLS struct TcpConn	TcpConn
	A single TCP connection context.

Variables
uint32_t	protocore_ap_ip
	Access-point IPv4 address (network byte order) for STA/AP interface tagging.
TcpConn	conn_pool [CONN_POOL_SLOTS]
	Static pool of connection contexts. Defined in protocol/protocol.c. Sized CONN_POOL_SLOTS: MAX_CONNS TCP slots plus any reserved internal dispatch slot(s) (HTTP/3); the TCP accept path only ever uses [0, MAX_CONNS).
Listener	listener_pool [MAX_LISTENERS]
	Static pool of listener contexts. Defined in server.c.

Detailed Description

Layer 4 (Transport) - the connection state every half of TCP reads.

RFC 9293 sec 3.3.1 calls these the key connection state variables. Here that is the pool slot: its lifecycle state, its receive ring, and the identity fields the layers above filter on. The server (sec 3.9.1.1 passive OPEN), the client (active OPEN), the protocol engine (sec 3.10) and the lower-level seam (sec 3.9.2) all read this header and none of them declares its own copy.

The event record itself is in evt.h, which this includes: the slot state below is _Atomic, which is C11 and not C++, so the header that reaches the sketches has to be the smaller one.

Concurrency model

Context	Reads	Writes
stack callbacks	anularis.vacant (to check)	anularis.put
main loop	anularis.available/read/peek	anularis.read/consume

The receive ring is a memoria_anularis ring over the slot's own aligned rx_buffer: one producer (the stack callbacks) and one consumer (the owning worker), with the ordering inside the ring. state is _Atomic, read and written through PROTO_ATOMIC_LOAD / PROTO_ATOMIC_STORE.

Backpressure (lossless) When a whole inbound segment will not fit the free ring space, the recv callback refuses it without taking ownership of the segment; the stack holds it and redelivers once the main loop has drained the ring, so no received byte is dropped. Requires RX_BUF_SIZE > one TCP segment (TCP_MSS).

Author

Douglas Quigg (dstroy0)

Date

2026

Definition in file common.h.

Macro Definition Documentation

PROTOCORE_PROTO_SLOT_NONE

#define PROTOCORE_PROTO_SLOT_NONE   0xFFu

Sentinel for TcpConn.proto_slot meaning "no per-protocol session bound".

Definition at line 84 of file common.h.

PROTOCORE_DSCP_UNSET

#define PROTOCORE_DSCP_UNSET   0xFF

The row carries no code point of its own; accept() takes the server-wide default.

Stated here rather than in diffserv.h because it is a value of Listener::dscp, which every build has: a port either names a code point or does not, and only whether the accept callback stamps one into the DS field depends on PROTOCORE_ENABLE_DIFFSERV.

Definition at line 161 of file common.h.

Typedef Documentation

TcpConn

typedef PROTOCORE_BEGIN_DECLS struct TcpConn TcpConn

A single TCP connection context.

Sized so that MAX_CONNS instances fit in a static array without fragmentation. All fields except the ring and the state may only be accessed from the main-loop task.

Variable Documentation

protocore_ap_ip

uint32_t protocore_ap_ip

extern

Access-point IPv4 address (network byte order) for STA/AP interface tagging.

Zero when no access point is configured. Set via set_ap_ip(); the accept callback tags each connection PROTOCORE_IF_WIFI_AP when its local IP equals this, else PROTOCORE_IF_WIFI_STA. Used by per-route interface filters.

conn_pool

TcpConn conn_pool[CONN_POOL_SLOTS]

extern

Static pool of connection contexts. Defined in protocol/protocol.c. Sized CONN_POOL_SLOTS: MAX_CONNS TCP slots plus any reserved internal dispatch slot(s) (HTTP/3); the TCP accept path only ever uses [0, MAX_CONNS).

listener_pool

Listener listener_pool[MAX_LISTENERS]

extern

Static pool of listener contexts. Defined in server.c.