Check last value before send the event, if no change no event.

Adding a boolean parameter similarly of existing function to know if we would send
the event.

Change-Id: I03ee17f656065e556fd2b72b160b140852b68dcc
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

3 files changed, 20 insertions, 9 deletions

diff --git a/CAN-binder/low-can-binding/can/can-bus.cpp b/CAN-binder/low-can-binding/can/can-bus.cpp
index 6f9e78d..0de8aeb 100644
--- a/CAN-binder/low-can-binding/can/can-bus.cpp
+++ b/CAN-binder/low-can-binding/can/can-bus.cpp
@@ -126,13 +126,17 @@ int can_bus_t::process_can_signals(can_message_t& can_message)
 		//DEBUG(binder_interface, "Nb elt matched string: %d", (int)s.count(std::string(sig.generic_name));
 		if( s.find(sig->get_name()) != s.end() && afb_event_is_valid(s[sig->get_name()]))
 		{
-			decoded_message = decoder_t::translateSignal(*sig, can_message, conf.get_can_signals());
+			bool send = true;
+			decoded_message = decoder_t::translateSignal(*sig, can_message, conf.get_can_signals(), &send);
 
-			openxc_SimpleMessage s_message = build_SimpleMessage(sig->get_name(), decoded_message);
-			vehicle_message = build_VehicleMessage(s_message);
+			if(send)
+			{
+				openxc_SimpleMessage s_message = build_SimpleMessage(sig->get_name(), decoded_message);
+				vehicle_message = build_VehicleMessage(s_message);
 
-			std::lock_guard<std::mutex> decoded_can_message_lock(decoded_can_message_mutex_);
-			push_new_vehicle_message(vehicle_message);
+				std::lock_guard<std::mutex> decoded_can_message_lock(decoded_can_message_mutex_);
+				push_new_vehicle_message(vehicle_message);
+			}
 			processed_signals++;
 		}
 	}
diff --git a/CAN-binder/low-can-binding/can/can-decoder.cpp b/CAN-binder/low-can-binding/can/can-decoder.cpp
index 902484e..e01e43b 100644
--- a/CAN-binder/low-can-binding/can/can-decoder.cpp
+++ b/CAN-binder/low-can-binding/can/can-decoder.cpp
@@ -147,23 +147,30 @@ openxc_DynamicField decoder_t::stateDecoder(can_signal_t& signal,
 /// @param[in] signal - The details of the signal to decode and forward.
 /// @param[in] message - The received CAN message that should contain this signal.
 /// @param[in] signals - an array of all active signals.
+/// @param[out] send - An output parameter that will be flipped to false if the value could
+///      not be decoded.
 ///
 /// The decoder returns an openxc_DynamicField, which may contain a number,
 /// string or boolean.
 ///
 openxc_DynamicField decoder_t::translateSignal(can_signal_t& signal, can_message_t& message,
-	const std::vector<can_signal_t>& signals)
+	const std::vector<can_signal_t>& signals, bool* send)
 {
 	float value = decoder_t::parseSignalBitfield(signal, message);
 	DEBUG(binder_interface, "%s: Decoded message from parseSignalBitfield: %f", __FUNCTION__, value);
 
-	bool send = true;
 	// Must call the decoders every time, regardless of if we are going to
 	// decide to send the signal or not.
 	openxc_DynamicField decoded_value = decoder_t::decodeSignal(signal,
-			value, signals, &send);
+			value, signals, send);
 
 	signal.set_received(true);
+
+	// Don't send if they is no changes
+	if ((signal.get_last_value() == value && !signal.get_send_same()) || !send )
+	{
+		*send = false;
+	}
 	signal.set_last_value(value);
 	return decoded_value;
 }
diff --git a/CAN-binder/low-can-binding/can/can-decoder.hpp b/CAN-binder/low-can-binding/can/can-decoder.hpp
index ebe1de2..15e0229 100644
--- a/CAN-binder/low-can-binding/can/can-decoder.hpp
+++ b/CAN-binder/low-can-binding/can/can-decoder.hpp
@@ -36,7 +36,7 @@ public:
 			float value, bool* send);
 
 	static openxc_DynamicField translateSignal(can_signal_t& signal, can_message_t& message,
-		const std::vector<can_signal_t>& signals);
+		const std::vector<can_signal_t>& signals, bool* send);
 
 	static openxc_DynamicField decodeSignal(can_signal_t& signal, const can_message_t& message,
 			const std::vector<can_signal_t>& signals, bool* send);