Example: Voted Channel with Dual Transport (Shared Memory + TCP/IP). More...

#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "rte/channel_link/rte_channel.h"
#include "rte/voter/rte_voter.h"
#include "rte/status/rte_status.h"

Include dependency graph for vital_channel_dual_transport.c:

Data Structures
struct	shm_queue_t
struct	tcp_channel_t
struct	multi_transport_channel_t
struct	train_command_t

Macros
#define	CHANNEL_COUNT 2U

Enumerations
enum	channel_type_t { CHANNEL_TYPE_SHARED_MEMORY , CHANNEL_TYPE_TCP }
	Opaque channel type that hides whether it's SHM or TCP. More...

Functions
static rte_status_t	shm_send (shm_queue_t q, const void data, size_t size)
static rte_status_t	shm_recv (shm_queue_t q, void data, size_t size)
static rte_status_t	tcp_send (tcp_channel_t ch, const void data, size_t size)
static rte_status_t	tcp_recv (tcp_channel_t ch, void data, size_t size)
static rte_status_t	channel_backend_send (void channel_handle, const void data, size_t size)
	OSAdapter send callback for rte_channel (dispatches to transport).
static rte_status_t	channel_backend_recv (void channel_handle, void data, size_t size, uint32_t timeout_ms __attribute__((unused)))
	OSAdapter receive callback for rte_channel (dispatches to transport).
static rte_status_t	example_setup_dual_redundancy (rte_channel_t channels[CHANNEL_COUNT], rte_voter_t *voter)
	Example: Initialize dual-transport channels plus a 2oo2 voter.
static rte_status_t	send_train_command (rte_voter_t voter, const train_command_t cmd)
	Send a train command to every registered channel (atomic broadcast).
static rte_status_t	receive_train_command (rte_voter_t voter, train_command_t cmd_out)
	Receive a train command via the voter (with 2oo2 voting).
static void	monitor_channel_health (rte_channel_t channels[CHANNEL_COUNT], rte_voter_t *voter)
	Monitor channel health and detect faults.
int	main (void)
	Main example.

Variables
static shm_queue_t	shm_queue_0 = {0}
static tcp_channel_t	tcp_ch_0 = {.socket = 0, .connected = true}
static multi_transport_channel_t	g_channel_0
static multi_transport_channel_t	g_channel_1

Detailed Description

Example: Voted Channel with Dual Transport (Shared Memory + TCP/IP).

Demonstrates how to:

Create two redundant communication links using different transports
Register them into a rte_voter_t for 2oo2 voting/redundancy (ADR-025)
Support user selection of online/standby channel configurations
Monitor health for fault detection

This pattern enables:

Online process communicates via fast shared memory to local standby
Online process communicates via TCP to remote standby (fallback)
Voting ensures data consistency across both standbies
If one channel fails, voting detects and triggers safe-state

ADR-025 split what used to be a single "vital channel" type (one transport handle + built-in N-way voting) into rte_channel (one link) plus rte_voter (voting across N registered links). This example registers one rte_channel_t per transport into one rte_voter_t configured for RTE_VOTING_2OO2.

Compile: gcc -std=c99 -Wall -Wextra -o vital_dual_transport \ vital_channel_dual_transport.c \ -I../include -L../build -lrte_channels -lrte_oal \ -lrte_core

Definition in file vital_channel_dual_transport.c.

Macro Definition Documentation

◆ CHANNEL_COUNT

#define CHANNEL_COUNT 2U

Definition at line 241 of file vital_channel_dual_transport.c.

Enumeration Type Documentation

◆ channel_type_t

enum channel_type_t

Opaque channel type that hides whether it's SHM or TCP.

This allows each rte_channel_t to wrap ANY transport. The callback functions dispatch based on channel type.

Definition at line 151 of file vital_channel_dual_transport.c.

Function Documentation

◆ shm_send()

rte_status_t shm_send	(	shm_queue_t *	q,
		const void *	data,
		size_t	size )

static

Definition at line 54 of file vital_channel_dual_transport.c.

◆ shm_recv()

rte_status_t shm_recv	(	shm_queue_t *	q,
		void *	data,
		size_t	size )

static

Definition at line 71 of file vital_channel_dual_transport.c.

◆ tcp_send()

rte_status_t tcp_send	(	tcp_channel_t *	ch,
		const void *	data,
		size_t	size )

static

Definition at line 101 of file vital_channel_dual_transport.c.

◆ tcp_recv()

rte_status_t tcp_recv	(	tcp_channel_t *	ch,
		void *	data,
		size_t	size )

static

Definition at line 121 of file vital_channel_dual_transport.c.

◆ channel_backend_send()

rte_status_t channel_backend_send	(	void *	channel_handle,
		const void *	data,
		size_t	size )

static

OSAdapter send callback for rte_channel (dispatches to transport).

Called by rte_channel_send() for one link. The callback hides the specific transport implementation.

Definition at line 180 of file vital_channel_dual_transport.c.

◆ channel_backend_recv()

rte_status_t channel_backend_recv	(	void *	channel_handle,
		void *	data,
		size_t	size,
		uint32_t timeout_ms	__attribute__(unused) )

static

OSAdapter receive callback for rte_channel (dispatches to transport).

Called by rte_channel_receive() for one link. The callback hides the specific transport implementation.

Definition at line 206 of file vital_channel_dual_transport.c.

◆ example_setup_dual_redundancy()

rte_status_t example_setup_dual_redundancy	(	rte_channel_t	channels[CHANNEL_COUNT],
		rte_voter_t *	voter )

static

Example: Initialize dual-transport channels plus a 2oo2 voter.

Configuration:

Channel 0: Shared Memory (fast, local standby)
Channel 1: TCP/IP (remote standby, reliable backup)
Voting: 2oo2 (both must agree)

Definition at line 251 of file vital_channel_dual_transport.c.

◆ send_train_command()

rte_status_t send_train_command	(	rte_voter_t *	voter,
		const train_command_t *	cmd )

static

Send a train command to every registered channel (atomic broadcast).

Definition at line 300 of file vital_channel_dual_transport.c.

◆ receive_train_command()

rte_status_t receive_train_command	(	rte_voter_t *	voter,
		train_command_t *	cmd_out )

static

Receive a train command via the voter (with 2oo2 voting).

Definition at line 321 of file vital_channel_dual_transport.c.

◆ monitor_channel_health()

void monitor_channel_health	(	rte_channel_t	channels[CHANNEL_COUNT],
		rte_voter_t *	voter )

static

Monitor channel health and detect faults.

Definition at line 345 of file vital_channel_dual_transport.c.

◆ main()

int main ( void )

Main example.

Definition at line 378 of file vital_channel_dual_transport.c.

Variable Documentation

◆ shm_queue_0

shm_queue_t shm_queue_0 = {0}

static

Definition at line 52 of file vital_channel_dual_transport.c.

◆ tcp_ch_0

tcp_channel_t tcp_ch_0 = {.socket = 0, .connected = true}

static

Definition at line 99 of file vital_channel_dual_transport.c.

◆ g_channel_0

multi_transport_channel_t g_channel_0

static

Initial value:

                                             = {
    .type = CHANNEL_TYPE_SHARED_MEMORY,
    .impl.shm = &shm_queue_0,
}

Definition at line 164 of file vital_channel_dual_transport.c.

◆ g_channel_1

multi_transport_channel_t g_channel_1

static

Initial value:

                                             = {
    .type = CHANNEL_TYPE_TCP,
    .impl.tcp = &tcp_ch_0,
}

Definition at line 169 of file vital_channel_dual_transport.c.

Data Structures

Macros

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ CHANNEL_COUNT

Enumeration Type Documentation

◆ channel_type_t

Function Documentation

◆ shm_send()

◆ shm_recv()

◆ tcp_send()

◆ tcp_recv()

◆ channel_backend_send()

◆ channel_backend_recv()

◆ example_setup_dual_redundancy()

◆ send_train_command()

◆ receive_train_command()

◆ monitor_channel_health()

◆ main()

Variable Documentation

◆ shm_queue_0

◆ tcp_ch_0

◆ g_channel_0

◆ g_channel_1