From aff547b738b274bd7189731ef6bde390b9834583 Mon Sep 17 00:00:00 2001
From: David Rebbe <drebbe@intrepidcs.com>
Date: Tue, 21 Jul 2026 17:07:06 +0000
Subject: [PATCH] C2: Report copied buffer lengths

---
 api/icsneoc2/icsneoc2.cpp | 22 +++++++++++++---------
 test/unit/icsneoc2.cpp    | 22 ++++++++++++++++++++++
 2 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/api/icsneoc2/icsneoc2.cpp b/api/icsneoc2/icsneoc2.cpp
index 91915fd..defe87d 100644
--- a/api/icsneoc2/icsneoc2.cpp
+++ b/api/icsneoc2/icsneoc2.cpp
@@ -465,11 +465,13 @@ icsneoc2_error_t icsneoc2_device_pcb_serial_get(const icsneoc2_device_t* device,
 		return icsneoc2_error_invalid_type;
 	}
 	const auto& data = *pcbSerial;
-	if(value) {
-		size_t copyLen = std::min(*value_length, data.size());
-		std::copy(data.begin(), data.begin() + copyLen, value);
+	if(!value) {
+		*value_length = data.size();
+		return icsneoc2_error_success;
 	}
-	*value_length = data.size();
+	size_t copyLen = std::min(*value_length, data.size());
+	std::copy(data.begin(), data.begin() + copyLen, value);
+	*value_length = copyLen;
 	return icsneoc2_error_success;
 }
 
@@ -515,14 +517,16 @@ icsneoc2_error_t icsneoc2_mac_network_id_get(const icsneoc2_mac_addr_entry_t* ma
 }
 
 icsneoc2_error_t icsneoc2_mac_address_get(const icsneoc2_mac_addr_entry_t* mac_address, uint8_t* value, size_t* value_length) {
-	if(!mac_address || !value || !value_length) {
+	if(!mac_address || !value_length) {
 		return icsneoc2_error_invalid_parameters;
 	}
-	if(value) {
-		size_t copyLen = std::min(*value_length, static_cast<size_t>(ICSNEO_MAC_ADDRESS_LEN));
-		std::copy(mac_address->address, mac_address->address + copyLen, value);
+	if(!value) {
+		*value_length = static_cast<size_t>(ICSNEO_MAC_ADDRESS_LEN);
+		return icsneoc2_error_success;
 	}
-	*value_length = static_cast<size_t>(ICSNEO_MAC_ADDRESS_LEN);
+	size_t copyLen = std::min(*value_length, static_cast<size_t>(ICSNEO_MAC_ADDRESS_LEN));
+	std::copy(mac_address->address, mac_address->address + copyLen, value);
+	*value_length = copyLen;
 	return icsneoc2_error_success;
 }
 
diff --git a/test/unit/icsneoc2.cpp b/test/unit/icsneoc2.cpp
index 04d39ab..55f7e1b 100644
--- a/test/unit/icsneoc2.cpp
+++ b/test/unit/icsneoc2.cpp
@@ -127,6 +127,28 @@ TEST(icsneoc2, test_icsneoc2_device_is_valid)
 	ASSERT_EQ(icsneoc2_error_invalid_parameters, icsneoc2_device_is_valid(NULL));
 }
 
+TEST(icsneoc2, test_icsneoc2_mac_address_get_query_length)
+{
+	icsneoc2_mac_addr_entry_t mac_address = {};
+	size_t value_length = 0;
+
+	ASSERT_EQ(icsneoc2_error_success, icsneoc2_mac_address_get(&mac_address, NULL, &value_length));
+	ASSERT_EQ(ICSNEO_MAC_ADDRESS_LEN, value_length);
+}
+
+TEST(icsneoc2, test_icsneoc2_mac_address_get_truncated_length)
+{
+	icsneoc2_mac_addr_entry_t mac_address = {};
+	const uint8_t expected[ICSNEO_MAC_ADDRESS_LEN] = {0x00, 0xFC, 0x70, 0x1E, 0x18, 0x70};
+	std::copy(std::begin(expected), std::end(expected), mac_address.address);
+
+	uint8_t value[3] = {};
+	size_t value_length = sizeof(value);
+	ASSERT_EQ(icsneoc2_error_success, icsneoc2_mac_address_get(&mac_address, value, &value_length));
+	ASSERT_EQ(sizeof(value), value_length);
+	ASSERT_EQ(0, memcmp(expected, value, sizeof(value)));
+}
+
 TEST(icsneoc2, test_icsneoc2_error_invalid_parameters_and_invalid_device)
 {
 	bool placeholderBool = false;