Add versioned persistent configuration protocol

adapter_configuration.cpp

@@ -0,0 +1,43 @@
+#include "adapter_configuration.h"
+
+AdapterConfiguration adapter_configuration_default() {
+    return {};
+}
+
+bool adapter_configuration_encode(const AdapterConfiguration& configuration,
+                                  uint8_t* output, size_t output_size) {
+    if (output == nullptr || output_size < ADAPTER_CONFIGURATION_ENCODED_SIZE ||
+        configuration.pairing_window_seconds <
+            ADAPTER_PAIRING_WINDOW_SECONDS_MIN ||
+        configuration.pairing_window_seconds >
+            ADAPTER_PAIRING_WINDOW_SECONDS_MAX) {
+        return false;
+    }
+
+    output[0] = static_cast<uint8_t>(configuration.pairing_window_seconds);
+    output[1] =
+        static_cast<uint8_t>(configuration.pairing_window_seconds >> 8);
+    output[2] = 0;
+    output[3] = 0;
+    return true;
+}
+
+bool adapter_configuration_decode(const uint8_t* payload, size_t payload_size,
+                                  AdapterConfiguration* output) {
+    if (payload == nullptr || output == nullptr ||
+        payload_size != ADAPTER_CONFIGURATION_ENCODED_SIZE ||
+        payload[2] != 0 || payload[3] != 0) {
+        return false;
+    }
+
+    const uint16_t pairing_window_seconds =
+        static_cast<uint16_t>(payload[0]) |
+        static_cast<uint16_t>(payload[1] << 8);
+    if (pairing_window_seconds < ADAPTER_PAIRING_WINDOW_SECONDS_MIN ||
+        pairing_window_seconds > ADAPTER_PAIRING_WINDOW_SECONDS_MAX) {
+        return false;
+    }
+
+    output->pairing_window_seconds = pairing_window_seconds;
+    return true;
+}