Agent Class Reference

EPOS-inspired Agent implementation using composition over inheritance. More...

#include <agent.h>

Inheritance diagram for Agent:

Public Types
typedef CAN::Message	Message
typedef Message::Origin	Address
typedef Message::Array	Value
typedef Message::Unit	Unit
typedef Message::Type	Type
typedef Message::Microseconds	Microseconds
typedef Periodic_Thread< Agent >	Thread
typedef CAN::Observer	Observer

Public Member Functions
	Agent (CAN *bus, const std::string &name, Unit unit, Type type, Address address, DataProducer producer, ResponseHandler handler, std::unique_ptr< ComponentData > data, bool external=true)
	Constructor for EPOS-inspired Agent using composition.
	~Agent ()
	Destructor with proper cleanup order.
Value	get (Unit unit)
	Get data using function pointer instead of virtual method.
void	handle_response (Message *msg)
	Handle response using function pointer instead of virtual method.
int	send (Unit unit, Microseconds period)
int	receive (Message *msg)
bool	running ()
void	external (const bool external)
const bool	external () const
std::string	name () const
void	set_csv_logger (const std::string &log_dir)
void	log_message (const Message &msg, const std::string &direction)
int	start_periodic_interest (Unit unit, Microseconds period)
	Start sending periodic INTEREST messages for the specified unit and period.
void	stop_periodic_interest ()
	Stop sending periodic INTEREST messages.
void	send_interest (Unit unit)
	Send a single INTEREST message (called by periodic thread)
void	update_interest_period (Microseconds new_period)
	Update the period for periodic interest sending.

Static Public Member Functions
static void *	run (void *arg)

Static Public Attributes
static const unsigned int	_units_per_vehicle = 5
static constexpr int	MAX_RESPONSES_PER_INTEREST = 5

Protected Member Functions
virtual void	reply (Unit unit)
	Reply method that calls function pointer instead of virtual method.
bool	thread_running ()
int	can_send (Message *msg)
Address	address () const

Detailed Description

EPOS-inspired Agent implementation using composition over inheritance.

This Agent class eliminates the "pure virtual method called" race condition by using function pointers instead of virtual methods. Following EPOS SmartData principles, components are pure data + function pairs rather than inheritance-based.

Key improvements:

• No virtual methods = no vtable race conditions
• Function-based composition instead of inheritance
• Type-safe component data management
• Same public API as original Agent for compatibility

Member Typedef Documentation

Address

typedef Message::Origin Agent::Address

Message

typedef CAN::Message Agent::Message

Microseconds

typedef Message::Microseconds Agent::Microseconds

Observer

typedef CAN::Observer Agent::Observer

Thread

typedef Periodic_Thread<Agent> Agent::Thread

Type

typedef Message::Type Agent::Type

Unit

typedef Message::Unit Agent::Unit

Value

typedef Message::Array Agent::Value

Constructor & Destructor Documentation

Agent()

Agent::Agent ( CAN *  bus, const std::string &  name, Unit  unit, Type  type, Address  address, DataProducer  producer, ResponseHandler  handler, std::unique_ptr< ComponentData >  data, bool  external = true  )

inline

Constructor for EPOS-inspired Agent using composition.

Creates an Agent that uses function pointers instead of virtual methods, eliminating the vtable race condition during destruction.

Parameters

bus	CAN bus for communication
name	Agent name for identification
unit	Data unit this agent handles
type	Agent type (INTEREST for producers, RESPONSE for consumers)
address	Network address
producer	Function pointer for data production (can be nullptr for consumers)
handler	Function pointer for response handling (can be nullptr for producers)
data	Component-specific data structure

~Agent()

Agent::~Agent ( )

inline

Destructor with proper cleanup order.

Ensures threads are properly joined before object destruction, eliminating the race condition that occurred with virtual methods.

Member Function Documentation

address()

Agent::Address Agent::address ( ) const

inlineprotected

can_send()

int Agent::can_send ( Message *  msg )

inlineprotected

external() [1/2]

const bool Agent::external ( ) const

inline

external() [2/2]

void Agent::external ( const bool  external )

inline

get()

Agent::Value Agent::get ( Unit  unit )

inline

Get data using function pointer instead of virtual method.

This is the key method that eliminates the race condition. Instead of calling a virtual method that could crash during destruction, we call a function pointer that was set during construction.

Parameters

unit	The data unit being requested

Returns

Value containing the generated data

handle_response()

void Agent::handle_response ( Message *  msg )

inline

Handle response using function pointer instead of virtual method.

Similar to get(), this uses a function pointer to avoid virtual method calls that could cause race conditions during destruction.

Parameters

msg	Pointer to the received message

log_message()

void Agent::log_message ( const Message &  msg, const std::string &  direction  )

inline

name()

std::string Agent::name ( ) const

inline

receive()

int Agent::receive ( Message *  msg )

inline

reply()

void Agent::reply ( Unit  unit )

inlineprotectedvirtual

Reply method that calls function pointer instead of virtual method.

This is the critical method where the race condition used to occur. Instead of calling the virtual get() method, we now call the function pointer directly, eliminating the vtable dependency.

Reimplemented in CSVAgent.

run()

void * Agent::run ( void *  arg )

inlinestatic

running()

bool Agent::running ( )

inline

send()

int Agent::send ( Unit  unit, Microseconds  period  )

inline

send_interest()

void Agent::send_interest ( Unit  unit )

inline

Send a single INTEREST message (called by periodic thread)

Parameters

unit	The data type unit

set_csv_logger()

void Agent::set_csv_logger ( const std::string &  log_dir )

inline

start_periodic_interest()

int Agent::start_periodic_interest ( Unit  unit, Microseconds  period  )

inline

Start sending periodic INTEREST messages for the specified unit and period.

Parameters

unit	The data type unit to request
period	The desired response period from producers

Returns

int Success/failure status

stop_periodic_interest()

void Agent::stop_periodic_interest ( )

inline

Stop sending periodic INTEREST messages.

thread_running()

bool Agent::thread_running ( )

inlineprotected

update_interest_period()

void Agent::update_interest_period ( Microseconds  new_period )

inline

Update the period for periodic interest sending.

Parameters

new_period

The new period to use

Member Data Documentation

_units_per_vehicle

const unsigned int Agent::_units_per_vehicle = 5

static

MAX_RESPONSES_PER_INTEREST

constexpr int Agent::MAX_RESPONSES_PER_INTEREST = 5

staticconstexpr

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The documentation for this class was generated from the following file:

• include/api/framework/agent.h