Implementation of the main CAN state machine dispatcher. More...

Functions
void	CanMainStatemachine_initialize (const interface_can_main_statemachine_t *interface_can_main_statemachine)
	Initializes the CAN main state machine.

can_statemachine_info_t *	CanMainStateMachine_get_can_statemachine_info (void)
	Returns a pointer to the internal state machine context (for testing/debugging).

bool	CanMainStatemachine_handle_duplicate_aliases (void)
	Checks for the has_duplicate_alias flag; resolves any duplicates found.

bool	CanMainStatemachine_handle_outgoing_can_message (void)
	Pops and transmits one CAN frame from the outgoing FIFO.

bool	CanMainStatemachine_handle_login_outgoing_can_message (void)
	Transmits the pending login frame (CID/RID/AMD) if one is flagged as valid.

bool	CanMainStatemachine_handle_try_enumerate_first_node (void)
	Starts node enumeration by fetching and processing the first node.

bool	CanMainStatemachine_handle_try_enumerate_next_node (void)
	Advances node enumeration to the next node.

bool	CanMainStatemachine_handle_listener_verification (void)
	Probes one listener alias for staleness and queues an AME if due.

void	CanMainStateMachine_run (void)
	Executes one cooperative iteration of the main CAN state machine.

Detailed Description

Implementation of the main CAN state machine dispatcher.

Copyright: Copyright (c) 2024, Jim Kueneman All rights reserved.

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Coordinates duplicate alias detection, CAN and login frame transmission, and node enumeration. Uses a cooperative multitasking pattern — each function does one unit of work and returns so other application code can run.

Author: Jim Kueneman

Date: 8 Mar 2026

Function Documentation

◆ CanMainStatemachine_initialize()

void CanMainStatemachine_initialize ( const interface_can_main_statemachine_t * interface_can_main_statemachine )

Initializes the CAN main state machine.

Registers the dependency-injection interface and prepares internal buffers.

Stores the interface pointer, clears the static login frame buffer, links it to the state machine context, and zeroes all context flags.

* @param interface_can_main_statemachine Pointer to the populated dependency interface.
*

Warning: Must be called once at startup after CanBufferStore_initialize().

◆ CanMainStateMachine_get_can_statemachine_info()

can_statemachine_info_t * CanMainStateMachine_get_can_statemachine_info ( void )

Returns a pointer to the internal state machine context (for testing/debugging).

Returns a pointer to the internal state machine context.

◆ CanMainStatemachine_handle_duplicate_aliases()

bool CanMainStatemachine_handle_duplicate_aliases ( void )

Checks for the has_duplicate_alias flag; resolves any duplicates found.

Scans the alias table, unregisters duplicates, and resets affected nodes.

Locks shared resources, reads the flag, calls _process_duplicate_aliases() if needed, then unlocks.

Returns: true if duplicates were found and processed, false if none.

◆ CanMainStatemachine_handle_outgoing_can_message()

bool CanMainStatemachine_handle_outgoing_can_message ( void )

Pops and transmits one CAN frame from the outgoing FIFO.

Pops one message from the outgoing CAN FIFO and attempts transmission.

Algorithm:

If no frame is held in the working slot, pop one from the FIFO (under lock).
If a frame is held, try to send it; free it (under lock) only on success.
Return true if a frame was pending (sent or not), false if FIFO was empty.

Returns: true if a frame was pending, false if the FIFO was empty.

Note: The frame is retried on the next call if the hardware buffer was busy.

◆ CanMainStatemachine_handle_login_outgoing_can_message()

bool CanMainStatemachine_handle_login_outgoing_can_message ( void )

Transmits the pending login frame (CID/RID/AMD) if one is flagged as valid.

Attempts to transmit the pending login frame (CID, RID, or AMD).

Clears login_outgoing_can_msg_valid only after successful transmission. Returns true if a login frame was pending (sent or retried), false if none.

◆ CanMainStatemachine_handle_try_enumerate_first_node()

bool CanMainStatemachine_handle_try_enumerate_first_node ( void )

Starts node enumeration by fetching and processing the first node.

Gets the first node and processes it through its appropriate state machine.

Returns false if enumeration is already active (node pointer non-NULL). Otherwise fetches the first node, runs its login state machine if still logging in, and returns true.

Returns: true if enumeration was started (or no nodes exist), false if already active.

◆ CanMainStatemachine_handle_try_enumerate_next_node()

bool CanMainStatemachine_handle_try_enumerate_next_node ( void )

Advances node enumeration to the next node.

Continues enumeration and processes the next node.

Fetches the next node and runs its login state machine if still logging in. Returns true when there are no more nodes (enumeration complete), false otherwise.

Returns: true when all nodes have been processed, false if more nodes remain.

◆ CanMainStatemachine_handle_listener_verification()

bool CanMainStatemachine_handle_listener_verification ( void )

Probes one listener alias for staleness and queues an AME if due.

Algorithm:

Call ListenerAliasTable_check_one_verification() with current tick
If non-zero node_id returned: get first node's alias, allocate a CAN buffer (with lock/unlock), build targeted AME, push to CAN FIFO (with lock/unlock)
Return true if an AME was queued, false otherwise

Returns: true if a probe AME was queued, false if nothing to do.

◆ CanMainStateMachine_run()

void CanMainStateMachine_run ( void )

Executes one cooperative iteration of the main CAN state machine.

Executes one iteration of the main CAN state machine.

Calls each handler in priority order, returning after the first one that does work. Listener verification runs unconditionally before the priority chain. Priority: duplicate aliases -> outgoing CAN frame -> login frame -> enumerate first node -> enumerate next node.

Functions