isotp-c/src/isotp/receive.h

87 lines
3.2 KiB
C

#ifndef __ISOTP_RECEIVE_H__
#define __ISOTP_RECEIVE_H__
#include <isotp/isotp.h>
#include <stdint.h>
#include <stdbool.h>
#ifdef __cplusplus
extern "C" {
#endif
/* Public: A handle for beginning and continuing receiving a single ISO-TP
* message - both single and multi-frame.
*
* Since an ISO-TP message may contain multiple frames, we need to keep a handle
* around while waiting for subsequent CAN messages to complete the message.
* This struct encapsulates the local state required.
*
* completed - True if the received message request is completely finished.
* success - True if the message request was successful. The value if this field
* isn't valid if 'completed' isn't true.
*/
typedef struct {
bool completed;
bool success;
/* Private */
uint32_t arbitration_id;
IsoTpMessageReceivedHandler message_received_callback;
uint16_t timeout_ms;
/* timeout_ms: ISO_TP_DEFAULT_RESPONSE_TIMEOUT, */
uint8_t* receive_buffer;
uint16_t received_buffer_size;
uint16_t incoming_message_size;
/* TODO timer callback for multi frame */
} IsoTpReceiveHandle;
/* Public: Initiate receiving a single ISO-TP message on a particular
* arbitration ID.
*
* Note that no actual CAN data has been received at this point - this just sets
* up a handle to be used when new CAN messages to arrive, so they can be parsed
* as potential single or multi-frame ISO-TP messages.
*
* shims - Low-level shims required to send and receive CAN messages, etc.
* arbitration_id - The arbitration ID to receive the message on.
* callback - an optional function to be called when the message is completely
* received (use NULL if no callback required).
*
* Returns a handle to be used with isotp_continue_receive when a new CAN frame
* arrives. The 'completed' field in the returned IsoTpReceiveHandle will be true
* when the message is completely sent.
*/
IsoTpReceiveHandle isotp_receive(IsoTpShims* shims,
const uint32_t arbitration_id, IsoTpMessageReceivedHandler callback);
/* Public: Continue to receive a an ISO-TP message, based on a freshly
* received CAN message.
*
* For a multi-frame ISO-TP message, this function must be called
* repeatedly whenever a new CAN message is received in order to complete
* receipt.
*
* TODO does this API work for if we wanted to receive an ISO-TP message and
* send our own flow control messages back?
*
* shims - Low-level shims required to send and receive CAN messages, etc.
* handle - An IsoTpReceiveHandle previously returned by isotp_receive(...).
* arbitration_id - The arbitration_id of the received CAN message.
* data - The data of the received CAN message.
* size - The size of the data in the received CAN message.
*
* Returns an IsoTpMessage with the 'completed' field set to true if a message
* was completely received. If 'completed' is false, more CAN frames are
* required to complete the messages, or the arbitration ID didn't match this
* handle. Keep passing the same handle to this function when CAN frames arrive.
*/
IsoTpMessage isotp_continue_receive(IsoTpShims* shims,
IsoTpReceiveHandle* handle, const uint32_t arbitration_id,
const uint8_t data[], const uint8_t size);
#ifdef __cplusplus
}
#endif
#endif /* __ISOTP_RECEIVE_H__ */