Module can_bus 

The C ABI for a node on a CAN bus.

A node is a SocketCAN socket on a kernel interface such as can0, on a Linux board, or a node on a bus simulated inside the program. pamoja_can_bus_join puts another node on the same bus, and a node hears every frame the others send and none of its own. Frames cross as the PamojaCanFrame handles of the framing calls; a filter is only scalars, so it crosses by value as PamojaCanFilter.

A receive on a simulated bus never waits: with nothing there it returns at once and counts its timeout in pamoja_can_bus_waited_micros.

Structs

PamojaCanBus

A node on a CAN bus. Opaque; release it with pamoja_can_bus_free.

PamojaCanFilter

A frame a node keeps: one whose identifier, masked, equals id, masked, and whose format is the filter’s.

Constants

PAMOJA_CAN_BUS_DEVICE

A bus kind: a kernel CAN interface reached through SocketCAN.

PAMOJA_CAN_BUS_SIMULATED

A bus kind: a bus inside the program.

Functions

pamoja_can_bus_clear_filters^⚠

Keeps every frame again, as a node does when it joins.

pamoja_can_bus_free^⚠

Releases a node; it leaves the bus. A null pointer is ignored.

pamoja_can_bus_join^⚠

Puts another node on the same bus: another socket on the same interface, or another node on the same simulated bus.

pamoja_can_bus_kind^⚠

Returns what a node’s bus is: PAMOJA_CAN_BUS_DEVICE or PAMOJA_CAN_BUS_SIMULATED, which a null handle also reports.

pamoja_can_bus_open^⚠

Opens a kernel CAN interface through SocketCAN, as one node on its bus.

pamoja_can_bus_receive^⚠

Takes the next frame the node keeps, waiting up to a timeout for one.

pamoja_can_bus_received^⚠

Returns how many frames a node has received, or 0 for a null handle.

pamoja_can_bus_send^⚠

Sends a frame to every other node on the bus.

pamoja_can_bus_sent^⚠

Returns how many frames a node has sent, or 0 for a null handle.

pamoja_can_bus_set_filters^⚠

Keeps only the frames that pass at least one of the filters, from now on. An empty list keeps nothing.

pamoja_can_bus_simulated

Makes a new bus inside the program, with the returned node the first on it.

pamoja_can_bus_waited_micros^⚠

Returns how long receives on a node have waited without a frame, in microseconds, whether or not the process slept through it, or 0 for a null handle.

pamoja_can_filter_exact

A filter that passes one identifier and nothing else.

pamoja_can_filter_matches

Reports whether a frame with an identifier passes a filter.

pamoja_can_filter_pgn

A filter that passes one J1939 parameter group at any priority, from any source, and for an addressed group, to any destination.