feat: Track consecutive frame index

1 files changed, 8 insertions, 1 deletions

diff --git a/src/message.cpp b/src/message.cpp
index 834fd87..0769533 100644
--- a/src/message.cpp
+++ b/src/message.cpp
@@ -11,6 +11,7 @@ void Message::copyFrom(const Message& other) {
 	this->can_id = other.can_id;
 	this->size = other.size;
 	this->received = other.received;
+	this->latest_index = other.latest_index;
 
 	this->msg = new unsigned char[this->size];
 	std::memcpy(this->msg, other.msg, this->size);
@@ -18,7 +19,7 @@ void Message::copyFrom(const Message& other) {
 
 /* Public */
 
-Message::Message(unsigned int can_id, const Frame& first_frame) : can_id(can_id), received(0) {
+Message::Message(unsigned int can_id, const Frame& first_frame) : can_id(can_id), received(0), latest_index(0) {
 	this->size = first_frame.get_size();
 	this->msg = new unsigned char[this->size];
 	this->receive_frame(first_frame);
@@ -41,6 +42,12 @@ Message& Message::operator=(const Message& other) {
 }
 
 void Message::receive_frame(const Frame& f) {
+	// This logic isn't really necessary, but I like to be thorough
+	if ((this->latest_index + 1) % 16 < f.get_index()) {
+		throw std::invalid_argument("A consecutive frame was lost!");
+	}
+	this->latest_index = f.get_index();
+
 	// For CFs we set the data size to 7 (the maximum), however, we may be expecting
 	// to receive less data (in the last CF).
 	size_t expects = std::min(this->size - this->received, f.get_data_size());