Expose device model in C API

The C++ API already provides access to the model of the connected device
in NitrokeyManager::get_connected_device_model().  This patch also
exposes this information in the C API by adding NK_get_device_model.  As
there might be no device connected, the function returns a boolean
indicating the connection status and writes the model of the connected
device to a pointer passed as an argument.

1 files changed, 24 insertions, 0 deletions

diff --git a/NK_C_API.cc b/NK_C_API.cc
index 8e005b8..56340ac 100644
--- a/NK_C_API.cc
+++ b/NK_C_API.cc
@@ -238,6 +238,30 @@ extern "C" {
 	}
 
 
+	NK_C_API bool NK_get_device_model(enum NK_device_model *out) {
+		if (out == nullptr) {
+			return false;
+		}
+		auto m = NitrokeyManager::instance();
+		try {
+			auto model = m->get_connected_device_model();
+			switch (model) {
+				case DeviceModel::PRO:
+				    *out = NK_PRO;
+				    return true;
+				case DeviceModel::STORAGE:
+				    *out = NK_STORAGE;
+				    return true;
+				default:
+				    /* unknown device -- should not happen */
+				    return false;
+			}
+		} catch (const DeviceNotConnected& e) {
+			return false;
+		}
+        }
+
+
 	void clear_string(std::string &s) {
 		std::fill(s.begin(), s.end(), ' ');
 	}