diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/obd2/obd2.c | 84 | ||||
| -rw-r--r-- | src/obd2/obd2.h | 30 |
2 files changed, 86 insertions, 28 deletions
diff --git a/src/obd2/obd2.c b/src/obd2/obd2.c index 7188af0d..d8ef190c 100644 --- a/src/obd2/obd2.c +++ b/src/obd2/obd2.c @@ -1,8 +1,12 @@ #include <obd2/obd2.h> +#define MODE_RESPONSE_OFFSET 0x40 +#define NEGATIVE_RESPONSE_MODE 0x7f #define MAX_DIAGNOSTIC_PAYLOAD_SIZE 6 #define MODE_BYTE_INDEX 0 #define PID_BYTE_INDEX 1 +#define NEGATIVE_RESPONSE_MODE_INDEX 1 +#define NEGATIVE_RESPONSE_NRC_INDEX 2 DiagnosticShims diagnostic_init_shims(LogShim log, SendCanMessageShim send_can_message, @@ -18,11 +22,13 @@ DiagnosticShims diagnostic_init_shims(LogShim log, DiagnosticRequestHandle diagnostic_request(DiagnosticShims* shims, DiagnosticRequest* request, DiagnosticResponseReceived callback) { DiagnosticRequestHandle handle = { - type: DIAGNOSTIC_REQUEST_TYPE_PID, + // TODO can we copy the request? + request: *request, callback: callback, success: false, completed: false }; + uint8_t payload[MAX_DIAGNOSTIC_PAYLOAD_SIZE]; payload[MODE_BYTE_INDEX] = request->mode; if(request->pid_length > 0) { @@ -125,22 +131,80 @@ DiagnosticResponse diagnostic_receive_can_frame(DiagnosticShims* shims, DiagnosticRequestHandle* handle, const uint16_t arbitration_id, const uint8_t data[], const uint8_t size) { - if(!handle->isotp_send_handle.completed) { - } else if(!handle->isotp_receive_handle.completed) { - } else { - shims->log("Handle is already completed"); - } - // TODO determine which isotp handler to pass it to based on our state - IsoTpMessage message = isotp_receive_can_frame(&handle->isotp_shims, - &handle->isotp_send_handle, arbitration_id, data, size); DiagnosticResponse response = { + arbitration_id: arbitration_id, success: false, completed: false }; - if(message.completed) { + if(!handle->isotp_send_handle.completed) { + // TODO when completing a send, this returns...a Message? we have to + // check when the isotp_send_handle is completed, and if it is, start + isotp_receive_can_frame(&handle->isotp_shims, + &handle->isotp_send_handle, arbitration_id, data, size); + } else if(!handle->isotp_receive_handle.completed) { + IsoTpMessage message = isotp_receive_can_frame(&handle->isotp_shims, + &handle->isotp_receive_handle, arbitration_id, data, size); + + if(message.completed) { + if(message.size > 0) { + response.mode = message.payload[0]; + if(response.mode == NEGATIVE_RESPONSE_MODE) { + if(message.size > NEGATIVE_RESPONSE_MODE_INDEX) { + // TODO we're setting the mode to the originating + // request for the error, so the user can confirm - i + // think this is OK since we're storing the failure + // status elsewhere, but think about it. + response.mode = message.payload[NEGATIVE_RESPONSE_MODE_INDEX]; + } + + if(message.size > NEGATIVE_RESPONSE_NRC_INDEX) { + response.negative_response_code = message.payload[NEGATIVE_RESPONSE_NRC_INDEX]; + } + response.success = false; + } else { + if(response.mode == handle->request.mode + MODE_RESPONSE_OFFSET) { + // hide the "response" version of the mode from the user + // if it matched + response.mode = handle->request.mode; + if(handle->request.pid_length > 0 && message.size > 1) { + copy_bytes_right_aligned(handle->request.pid, sizeof(handle->request.pid), + PID_BYTE_INDEX, handle->request.pid_length, response.pid, + sizeof(response.pid)); + } + + uint8_t payload_index = 1 + handle->request.pid_length; + response.payload_length = message.size - payload_index; + if(response.payload_length > 0) { + memcpy(response.payload, &message.payload[payload_index], + response.payload_length); + } + response.success = true; + } else { + shims->log("Response was for a mode %d request, not our mode %d request", + response.mode - MODE_RESPONSE_OFFSET, + handle->request.mode); + } + } + } + + response.completed = true; + // TODO what does it mean for the handle to be successful, vs. the + // request to be successful? if we get a NRC, is that a successful + // request? + handle->success = true; + handle->completed = true; + + if(handle->callback != NULL) { + handle->callback(&response); + } + } + + } else { + shims->log("Handle is already completed"); } + return response; } // TODO everything below here is for future work...not critical for now. diff --git a/src/obd2/obd2.h b/src/obd2/obd2.h index 727b816f..75894835 100644 --- a/src/obd2/obd2.h +++ b/src/obd2/obd2.h @@ -9,10 +9,20 @@ extern "C" { #endif +// TODO This isn't true for multi frame messages - we may need to dynamically +// allocate this in the future #define MAX_OBD2_PAYLOAD_LENGTH 7 #define VIN_LENGTH 17 +typedef enum { + DIAGNOSTIC_REQUEST_TYPE_PID, + DIAGNOSTIC_REQUEST_TYPE_DTC, + DIAGNOSTIC_REQUEST_TYPE_MIL_STATUS, + DIAGNOSTIC_REQUEST_TYPE_VIN +} DiagnosticRequestType; + typedef struct { + DiagnosticRequestType type; uint16_t arbitration_id; uint8_t mode; uint16_t pid; @@ -69,13 +79,8 @@ typedef struct { uint8_t mode; bool success; bool completed; - // if mode is one with a PID, read the correct numbers of PID bytes (1 or 2) - // into this field, then store the remainder of the payload in the payload - // field uint16_t pid; DiagnosticNegativeResponseCode negative_response_code; - // if response mode is a negative response, read first byte of payload into - // NRC and store remainder of payload in payload field uint8_t payload[MAX_OBD2_PAYLOAD_LENGTH]; uint8_t payload_length; } DiagnosticResponse; @@ -109,25 +114,14 @@ typedef struct { float max_value; } DiagnosticParameter; -typedef enum { - DIAGNOSTIC_REQUEST_TYPE_PID, - DIAGNOSTIC_REQUEST_TYPE_DTC, - DIAGNOSTIC_REQUEST_TYPE_MIL_STATUS, - DIAGNOSTIC_REQUEST_TYPE_VIN -} DiagnosticRequestType; - typedef struct { + DiagnosticRequest request; bool success; bool completed; + IsoTpShims isotp_shims; IsoTpHandle isotp_send_handle; IsoTpHandle isotp_receive_handle; - // TODO the Handle may need to keep the original request, otherwise we can't - // compare an incoming CAN message to see if it matches the service / PID! - // TODO i'm not sure this type/callback in here is too useful - see the - // comments in obd2.c:diagnostic_request - - DiagnosticRequestType type; DiagnosticResponseReceived callback; DiagnosticMilStatusReceived mil_status_callback; DiagnosticVinReceived vin_callback; |