decoder: Fix bit_position swapping

-Added an attribute to signals that tells if the bit_position
has been swapped.
-Test if bit_size and bit_position gives an "out of range" data

Bug-AGL: SPEC-3022

Change-Id: I589565ca923ec807da2d4f0db7c4c92fb737b579
Signed-off-by: Corentin Le Gall <corentin.legall@iot.bzh>
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

4 files changed, 25 insertions, 1 deletions

diff --git a/low-can-binding/can/can-decoder.cpp b/low-can-binding/can/can-decoder.cpp
index 19594afa..76ea79e6 100644
--- a/low-can-binding/can/can-decoder.cpp
+++ b/low-can-binding/can/can-decoder.cpp
@@ -350,9 +350,10 @@ openxc_DynamicField decoder_t::decode_state(signal_t& signal, std::shared_ptr<me
 ///
 openxc_DynamicField decoder_t::translate_signal(signal_t& signal, std::shared_ptr<message_t> message, bool* send)
 {
-	if(!signal.get_message()->frame_layout_is_little())
+	if(!signal.get_message()->frame_layout_is_little() && !signal.bit_position_is_swapped())
 	{
 		signal.set_bit_position(converter_t::bit_position_swap(signal.get_bit_position(),signal.get_bit_size()));
+		signal.bit_position_is_swapped_reverse();
 	}
 	// Must call the decoders every time, regardless of if we are going to
 	// decide to send the signal or not.
diff --git a/low-can-binding/can/signals.cpp b/low-can-binding/can/signals.cpp
index da8df988..28246a05 100755
--- a/low-can-binding/can/signals.cpp
+++ b/low-can-binding/can/signals.cpp
@@ -71,6 +71,7 @@ signal_t::signal_t(
 	, sign_{sign}
 	, bit_sign_position_{bit_sign_position}
 	, unit_{unit}
+	,bit_position_is_swapped_{false}
 {}
 
 signal_t::signal_t(
@@ -104,6 +105,7 @@ signal_t::signal_t(
 	, decoder_{decoder}
 	, encoder_{encoder}
 	, received_{received}
+	, bit_position_is_swapped_{false}
 {}
 
 std::shared_ptr<message_definition_t> signal_t::get_message() const
@@ -251,3 +253,13 @@ const std::string signal_t::get_unit() const
 {
 	return unit_;
 }
+
+bool signal_t::bit_position_is_swapped() const
+{
+	return bit_position_is_swapped_;
+}
+
+void signal_t::bit_position_is_swapped_reverse()
+{
+	bit_position_is_swapped_ = !bit_position_is_swapped_;
+}
diff --git a/low-can-binding/can/signals.hpp b/low-can-binding/can/signals.hpp
index bf779981..5f143753 100755
--- a/low-can-binding/can/signals.hpp
+++ b/low-can-binding/can/signals.hpp
@@ -111,6 +111,8 @@ private:
 	sign_t sign_; /* !< sign_ - if the data is signed it indicates the encode */
 	int32_t bit_sign_position_; /*!< bit_sign_position_ - The bit that indicates the sign of the signal in its CAN message*/
 	std::string unit_; /* !< unit_ - The unit of the data */
+	bool bit_position_is_swapped_; /* !<bit_position_is_swapped_- True if the signal's bit position has been
+										swapped (refer to converter_t::bit_position_swap()). Default is false.*/
 
 public:
 
@@ -177,10 +179,12 @@ public:
 	sign_t get_sign() const;
 	int32_t get_bit_sign_position() const;
 	const std::string get_unit() const;
+	bool bit_position_is_swapped() const;
 
 	void set_parent(std::shared_ptr<message_definition_t> parent);
 	void set_received(bool r);
 	void set_last_value(float val);
 	void set_timestamp(uint64_t timestamp);
 	void set_bit_position(uint32_t bit_position);
+	void bit_position_is_swapped_reverse();
 };
diff --git a/low-can-binding/utils/converter.cpp b/low-can-binding/utils/converter.cpp
index f790fc00..9e70bc95 100644
--- a/low-can-binding/utils/converter.cpp
+++ b/low-can-binding/utils/converter.cpp
@@ -69,6 +69,13 @@ uint32_t converter_t::bit_position_swap(uint32_t bit_position,uint32_t bit_size)
 {
 	uint32_t start_byte_position = (uint32_t)(bit_position/8);
 	uint32_t bit_size_rest = bit_size;
+
+	if((int)(bit_size-(8 + start_byte_position*8-bit_position%8))>0)
+	{
+		AFB_ERROR("Error: bit_position and bit_size getting out of range");
+		return bit_position;
+	}
+
 	if(bit_size<=8 && ((bit_position+bit_size)%8==bit_size || (bit_position+bit_size)%8==0))
 	{
 		return (uint32_t)(start_byte_position*8 + (8-bit_size));