ISO-TP (ISO 15765-2) Support Library in C
================================

## API

First, set up some shim functions to your lower level system:

    void debug(const char* format, ...) {
        ...
    }

    void send_can(const uint16_t arbitration_id, const uint8_t* data,
            const uint8_t size) {
        ...
    }

    void set_timer(uint16_t time_ms, void (*callback)) {
        ...
    }

Then, set up a callback and send an ISO-TP message:

    // this is your callback for when the message is completely sent - it's
    // optional
    void message_sent(const IsoTpMessage* message, const bool success) {
        // You received the message! Do something with it.
    }

    IsoTpShim shims = isotp_init_shims(debug, send_can, set_timer);
    IsoTpHandle handle = isotp_send(&shims, 0x100, NULL, 0, message_sent);

    if(handle.completed) {
        if(!handle.success) {
            // something happened and it already failed - possibly we aren't able to
            // send CAN messages
            return;
        } else {
            // If the message fit in a single frame, it's already been sent and
            you're done
        }
    } else {
        while(true) {
            // Continue to read from CAN, passing off each message to the handle
            bool complete = isotp_receive_can_frame(&shims, &handle, 0x100, data, size);

            if(complete && handle.completed) {
                if(handle.success) {
                    // All frames of the message have now been sent, following
                    // whatever flow control feedback it got from the receiver
                } else {
                    // the message was unable to be sent and we bailed - fatal
                    // error!
                }
            }
        }
    }

Finally, receive an ISO-TP message:

    // This is your callback for when a complete ISO-TP message is received at
    // the arbitration ID you specify - it's optional. The completed message is
    // also returned by isotp_receive_can_frame
    void message_received(const IsoTpMessage* message) {
    }

    IsoTpHandle handle = isotp_receive(&shims, 0x100, message_received);
    if(!handle.success) {
        // something happened and it already failed - possibly we aren't able to
        // send CAN messages
    } else {
        while(true) {
            // Continue to read from CAN, passing off each message to the handle
            IsoTp message = isotp_receive_can_frame(&shims, &handle, 0x100, data, size);

            if(message.completed && handle.completed) {
                if(handle.success) {
                    // A message has been received successfully
                } else {
                    // Fatal error - we weren't able to receive a message and
                    // gave up trying. A message using flow control may have
                    // timed out.
                }
            }
        }
    }

// TODO add an optional dispatcher to handle multiple open requests

## Testing

The library includes a test suite that uses the `check` C unit test library.

    $ make test

## Authors

Chris Peplin cpeplin@ford.com

## License

Copyright (c) 2013 Ford Motor Company

Licensed under the BSD license.