1 files changed, 89 insertions, 0 deletions
diff --git a/libs/isotp-c/src/isotp/send.c b/libs/isotp-c/src/isotp/send.c
new file mode 100644
index 0000000..e849bb2
--- /dev/null
+++ b/libs/isotp-c/src/isotp/send.c
@@ -0,0 +1,89 @@
+#include <isotp/send.h>
+#include <bitfield/bitfield.h>
+#include <string.h>
+
+#define PCI_NIBBLE_INDEX 0
+#define PAYLOAD_LENGTH_NIBBLE_INDEX 1
+#define PAYLOAD_BYTE_INDEX 1
+
+void isotp_complete_send(IsoTpShims* shims, IsoTpMessage* message,
+        bool status, IsoTpMessageSentHandler callback) {
+    if(callback != NULL) {
+        callback(message, status);
+    }
+}
+
+IsoTpSendHandle isotp_send_single_frame(IsoTpShims* shims, IsoTpMessage* message,
+        IsoTpMessageSentHandler callback) {
+    IsoTpSendHandle handle = {
+        success: false,
+        completed: true
+    };
+
+    uint8_t can_data[CAN_MESSAGE_BYTE_SIZE] = {0};
+    if(!set_nibble(PCI_NIBBLE_INDEX, PCI_SINGLE, can_data, sizeof(can_data))) {
+        shims->log("Unable to set PCI in CAN data");
+        return handle;
+    }
+
+    if(!set_nibble(PAYLOAD_LENGTH_NIBBLE_INDEX, message->size, can_data,
+                sizeof(can_data))) {
+        shims->log("Unable to set payload length in CAN data");
+        return handle;
+    }
+
+    if(message->size > 0) {
+        memcpy(&can_data[1], message->payload, message->size);
+    }
+
+    shims->send_can_message(message->arbitration_id, can_data,
+            shims->frame_padding ? 8 : 1 + message->size);
+    handle.success = true;
+    isotp_complete_send(shims, message, true, callback);
+    return handle;
+}
+
+IsoTpSendHandle isotp_send_multi_frame(IsoTpShims* shims, IsoTpMessage* message,
+        IsoTpMessageSentHandler callback) {
+    // TODO make sure to copy message into a local buffer
+    shims->log("Only single frame messages are supported");
+    IsoTpSendHandle handle = {
+        success: false,
+        completed: true
+    };
+    // TODO need to set sending and receiving arbitration IDs separately if we
+    // can't always just add 0x8 (and I think we can't)
+    return handle;
+}
+
+IsoTpSendHandle isotp_send(IsoTpShims* shims, const uint16_t arbitration_id,
+        const uint8_t payload[], uint16_t size,
+        IsoTpMessageSentHandler callback) {
+    IsoTpMessage message = {
+        arbitration_id: arbitration_id,
+        size: size
+    };
+
+    memcpy(message.payload, payload, size);
+    if(size < 8) {
+        return isotp_send_single_frame(shims, &message, callback);
+    } else {
+        return isotp_send_multi_frame(shims, &message, callback);
+    }
+}
+
+bool isotp_continue_send(IsoTpShims* shims, IsoTpSendHandle* handle,
+        const uint16_t arbitration_id, const uint8_t data[],
+        const uint8_t size) {
+    // TODO this will need to be tested when we add multi-frame support,
+    // which is when it'll be necessary to pass in CAN messages to SENDING
+    // handles.
+    if(handle->receiving_arbitration_id != arbitration_id) {
+        if(shims->log != NULL) {
+            shims->log("The arb ID 0x%x doesn't match the expected tx continuation ID 0x%x",
+                    arbitration_id, handle->receiving_arbitration_id);
+        }
+        return false;
+    }
+    return false;
+}