src/isotp/isotp.c

   1 #include <isotp/isotp.h>
   2 #include <isotp/receive.h>
   3 #include <bitfield/bitfield.h>
   4
   5 const uint8_t ISO_TP_DEFAULT_RESPONSE_TIMEOUT = 100;
   6 const bool ISO_TP_DEFAULT_FRAME_PADDING_STATUS = true;
   7
   8 /* void isotp_set_timeout(IsoTpHandler* handler, uint16_t timeout_ms) { */
   9     /* handler->timeout_ms = timeout_ms; */
  10 /* } */
  11
  12 IsoTpShims isotp_init_shims(LogShim log, SendCanMessageShim send_can_message,
  13         SetTimerShim set_timer) {
  14     IsoTpShims shims = {
  15         log: log,
  16         send_can_message: send_can_message,
  17         set_timer: set_timer
  18     };
  19     return shims;
  20 }
  21
  22 void isotp_message_to_string(const IsoTpMessage* message, char* destination,
  23         size_t destination_length) {
  24     // TODO why is this still not printing the entire payload?
  25     snprintf(destination, destination_length, "ID: 0x%02x, Payload: 0x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
  26             message->arbitration_id,
  27             message->payload[0],
  28             message->payload[1],
  29             message->payload[2],
  30             message->payload[3],
  31             message->payload[4],
  32             message->payload[5],
  33             message->payload[6],
  34             message->payload[7]);
  35 }
  36
  37 IsoTpMessage isotp_receive_can_frame(IsoTpShims* shims, IsoTpHandle* handle,
  38         const uint16_t arbitration_id, const uint8_t data[],
  39         const uint8_t data_length) {
  40     IsoTpMessage message = {
  41         arbitration_id: arbitration_id,
  42         completed: false,
  43         payload: {0},
  44         size: 0
  45     };
  46
  47     if(data_length < 1) {
  48         return message;
  49     }
  50
  51     if(handle->type == ISOTP_HANDLE_RECEIVING) {
  52         if(handle->receive_handle.arbitration_id != arbitration_id) {
  53             if(shims->log != NULL)  {
  54                 shims->log("The arb ID 0x%x doesn't match the expected rx ID 0x%x",
  55                         arbitration_id, handle->receive_handle.arbitration_id);
  56             }
  57             return message;
  58         }
  59     } else if(handle->type == ISOTP_HANDLE_SENDING) {
  60         if(handle->send_handle.receiving_arbitration_id != arbitration_id) {
  61             if(shims->log != NULL) {
  62                 shims->log("The arb ID 0x%x doesn't match the expected tx continuation ID 0x%x",
  63                         arbitration_id, handle->send_handle.receiving_arbitration_id);
  64             }
  65             return message;
  66         }
  67     } else {
  68         shims->log("The ISO-TP handle is corrupt");
  69         return message;
  70     }
  71
  72     IsoTpProtocolControlInformation pci = (IsoTpProtocolControlInformation)
  73             get_nibble(data, data_length, 0);
  74
  75     uint8_t payload_length = get_nibble(data, data_length, 1);
  76     uint8_t payload[payload_length];
  77     if(payload_length > 0 && data_length > 0) {
  78         memcpy(payload, &data[1], payload_length);
  79     }
  80
  81     // TODO this is set up to handle rx a response with a payload, but not to
  82     // handle flow control responses for multi frame messages that we're in the
  83     // process of sending
  84
  85     switch(pci) {
  86         case PCI_SINGLE: {
  87             if(payload_length > 0) {
  88                 memcpy(message.payload, payload, payload_length);
  89             }
  90             message.size = payload_length;
  91             message.completed = true;
  92             handle->success = true;
  93             handle->completed = true;
  94             isotp_handle_single_frame(handle, &message);
  95             break;
  96          }
  97         default:
  98             shims->log("Only single frame messages are supported");
  99             break;
 100     }
 101     return message;
 102 }