UAVCAN: redundant sensors support

src/modules/uavcan/sensors/sensor_bridge.cpp

@@ -36,12 +36,15 @@
  */
 
 #include "sensor_bridge.hpp"
-#include <systemlib/err.h>
+#include <cassert>
 
 #include "gnss.hpp"
 #include "mag.hpp"
 #include "baro.hpp"
 
+/*
+ * IUavcanSensorBridge
+ */
 IUavcanSensorBridge* IUavcanSensorBridge::make(uavcan::INode &node, const char *bridge_name)
 {
 	/*
@@ -64,3 +67,91 @@ void IUavcanSensorBridge::print_known_names(const char *prefix)
 	printf("%s%s\n", prefix, UavcanMagnetometerBridge::NAME);
 	printf("%s%s\n", prefix, UavcanBarometerBridge::NAME);
 }
+
+/*
+ * UavcanCDevSensorBridgeBase
+ */
+UavcanCDevSensorBridgeBase::~UavcanCDevSensorBridgeBase()
+{
+	for (unsigned i = 0; i < _max_channels; i++) {
+		if (_channels[i].redunancy_channel_id >= 0) {
+			(void)unregister_class_devname(_class_devname, _channels[i].class_instance);
+		}
+	}
+	delete [] _orb_topics;
+	delete [] _channels;
+}
+
+void UavcanCDevSensorBridgeBase::publish(const int redundancy_channel_id, const void *report)
+{
+	Channel *channel = nullptr;
+
+	// Checking if such channel already exists
+	for (unsigned i = 0; i < _max_channels; i++) {
+		if (_channels[i].redunancy_channel_id == redundancy_channel_id) {
+			channel = _channels + i;
+			break;
+		}
+	}
+
+	// No such channel - try to create one
+	if (channel == nullptr) {
+		if (_out_of_channels) {
+			return;           // Give up immediately - saves some CPU time
+		}
+
+		log("adding channel %d...", redundancy_channel_id);
+
+		// Search for the first free channel
+		for (unsigned i = 0; i < _max_channels; i++) {
+			if (_channels[i].redunancy_channel_id < 0) {
+				channel = _channels + i;
+				break;
+			}
+		}
+
+		// No free channels left
+		if (channel == nullptr) {
+			_out_of_channels = true;
+			log("out of channels");
+			return;
+		}
+
+		// Ask the CDev helper which class instance we can take
+		const int class_instance = register_class_devname(_class_devname);
+		if (class_instance < 0 || class_instance >= int(_max_channels)) {
+			_out_of_channels = true;
+			log("out of class instances");
+			(void)unregister_class_devname(_class_devname, class_instance);
+			return;
+		}
+
+		// Publish to the appropriate topic, abort on failure
+		channel->orb_id               = _orb_topics[class_instance];
+		channel->redunancy_channel_id = redundancy_channel_id;
+		channel->class_instance       = class_instance;
+
+		channel->orb_advert = orb_advertise(channel->orb_id, report);
+		if (channel->orb_advert < 0) {
+			log("ADVERTISE FAILED");
+			*channel = Channel();
+			return;
+		}
+
+		log("channel %d class instance %d ok", channel->redunancy_channel_id, channel->class_instance);
+	}
+	assert(channel != nullptr);
+
+	(void)orb_publish(channel->orb_id, channel->orb_advert, report);
+}
+
+unsigned UavcanCDevSensorBridgeBase::get_num_redundant_channels() const
+{
+	unsigned out = 0;
+	for (unsigned i = 0; i < _max_channels; i++) {
+		if (_channels[i].redunancy_channel_id >= 0) {
+			out += 1;
+		}
+	}
+	return out;
+}