Add support for multi-frame responses (#4)

[apps/agl-service-can-low-level.git] / src / isotp / isotp_types.h

diff --git a/src/isotp/isotp_types.h b/src/isotp/isotp_types.h
index d9fe460..6ae3a79 100644 (file)
--- a/src/isotp/isotp_types.h
+++ b/src/isotp/isotp_types.h
@@ -9,8 +9,14 @@
 #define MAX_ISO_TP_MESSAGE_SIZE 4096
 // TODO we want to avoid malloc, and we can't be allocated 4K on the stack for
 // each IsoTpMessage, so for now we're setting an artificial max message size
-// here - since we only handle single frame messages, 8 bytes is plenty.
-#define OUR_MAX_ISO_TP_MESSAGE_SIZE 8
+// here - for most multi-frame use cases, 256 bytes is plenty.
+#define OUR_MAX_ISO_TP_MESSAGE_SIZE 256
+
+/* Private: IsoTp nibble specifics for PCI and Payload.
+ */
+#define PCI_NIBBLE_INDEX 0
+#define PAYLOAD_LENGTH_NIBBLE_INDEX 1
+#define PAYLOAD_BYTE_INDEX 1
 
 /* Private: The default timeout to use when waiting for a response during a
  * multi-frame send or receive.
@@ -30,18 +36,20 @@ extern "C" {
  * completed - An IsoTpMessage is the return value from a few functions - this
  *      attribute will be true if the message is actually completely received.
  *      If the function returns but is only partially through receiving the
- *      message, this will be false and you should not consider the other data
- *      to be valid.
+ *      message, this will be false, the multi_frame attribute will be true,
+ *      and you should not consider the other data to be valid.
+ * multi_frame - Designates the message is being built with multi-frame.
  * arbitration_id - The arbitration ID of the message.
  * payload - The optional payload of the message - don't forget to check the
  *      size!
  * size -  The size of the payload. The size will be 0 if there is no payload.
  */
 typedef struct {
-    const uint16_t arbitration_id;
+    const uint32_t arbitration_id;
     uint8_t payload[OUR_MAX_ISO_TP_MESSAGE_SIZE];
     uint16_t size;
     bool completed;
+    bool multi_frame;
 } IsoTpMessage;
 
 /* Public: The type signature for an optional logging function, if the user
@@ -60,7 +68,7 @@ typedef void (*LogShim)(const char* message, ...);
  *
  * Returns true if the CAN message was sent successfully.
  */
-typedef bool (*SendCanMessageShim)(const uint16_t arbitration_id,
+typedef bool (*SendCanMessageShim)(const uint32_t arbitration_id,
         const uint8_t* data, const uint8_t size);
 
 /* Public: The type signature for a... TODO, not used yet.
@@ -96,11 +104,20 @@ typedef void (*IsoTpCanFrameSentHandler)(const IsoTpMessage* message);
  * with the wider system.
  *
  * Use the isotp_init_shims(...) function to create an instance of this struct.
+ *
+ * By default, all CAN frames sent from this device in the process of an ISO-TP
+ * message are padded out to a complete 8 byte frame. This is often required by
+ * ECUs. To disable this feature, change the 'frame_padding' field to false on
+ * the IsoTpShims object returned from isotp_init_shims(...).
+ *
+ * frame_padding - true if outgoing CAN frames should be padded to a full 8
+ *      bytes.
  */
 typedef struct {
     LogShim log;
     SendCanMessageShim send_can_message;
     SetTimerShim set_timer;
+    bool frame_padding;
 } IsoTpShims;
 
 /* Private: PCI types, for identifying each frame of an ISO-TP message.