2 * Copyright (C) 2015, 2016 "IoT.bzh"
3 * Author "Romain Forlot" <romain.forlot@iot.bzh>
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
18 #include "can-encoder.hpp"
20 #include "canutil/write.h"
21 #include "../utils/openxc-utils.hpp"
22 #include "message-definition.hpp"
23 #include "../utils/converter.hpp"
26 * @brief Allows to encode data for a signal
28 * @param sig The signal to know its location
29 * @param data The data to encode
30 * @param filter If true that will generate the filter BCM for the signal
31 * @param factor If true that will use the factor of the signal else 1
32 * @param offset If true that will use the offset of the signal else 0
34 void encoder_t::encode_data(std::shared_ptr<signal_t> sig, std::vector<uint8_t> &data, bool filter, bool factor, bool offset)
36 uint32_t bit_size = sig->get_bit_size();
37 uint32_t bit_position = sig->get_bit_position();
38 float factor_v = factor ? sig->get_factor() : 1;
39 float offset_v = offset ? sig->get_offset() : 0;
41 int new_start_byte = 0;
43 uint8_t new_start_bit = 0;
44 uint8_t new_end_bit = 0;
46 converter_t::signal_to_bits_bytes(bit_position, bit_size, new_start_byte, new_end_byte, new_start_bit, new_end_bit);
47 std::vector<uint8_t> data_signal(new_end_byte - new_start_byte + 1);
51 for (auto& elt: data_signal)
53 uint8_t mask_first_v = static_cast<uint8_t>(0xFF << new_start_bit);
54 uint8_t mask_last_v = static_cast<uint8_t>(0xFF >> (7 - new_end_bit));
56 if(new_start_byte == new_end_byte)
58 data_signal[0] = mask_first_v & mask_last_v;
62 data_signal[0] = mask_first_v;
63 data_signal[new_end_byte - new_start_byte] = mask_last_v;
68 bitfield_encode_float(sig->get_last_value(),
77 for(size_t i = new_start_byte; i <= new_end_byte ; i++)
78 data[i] = data[i] | data_signal[i-new_start_byte];
82 * @brief Allows to build a multi frame message with correct data to be send
84 * @param signal The CAN signal to write, including the bit position and bit size.
85 * @param value The encoded integer value to write in the CAN signal.
86 * @param message A multi frame message to complete
87 * @param factor If true that will use the factor of the signal else 1
88 * @param offset If true that will use the offset of the signal else 0
89 * @return message_t* The message that is generated
91 message_t* encoder_t::build_frame(const std::shared_ptr<signal_t>& signal, uint64_t value, message_t *message, bool factor, bool offset)
93 signal->set_last_value(static_cast<float>(value));
94 std::vector<uint8_t> data(message->get_length(), 0);
96 for(const auto& sig: signal->get_message()->get_signals())
97 encode_data(sig, data, false, factor, offset);
99 message->set_data(data);
104 * @brief Allows to build a message_t with correct data to be send
106 * @param signal The CAN signal to write, including the bit position and bit size.
107 * @param value The encoded integer value to write in the CAN signal.
108 * @param factor If true that will use the factor of the signal else 1
109 * @param offset If true that will use the offset of the signal else 0
110 * @return message_t* The message that is generated
112 message_t* encoder_t::build_message(const std::shared_ptr<signal_t>& signal, uint64_t value, bool factor, bool offset)
115 std::vector<uint8_t> data;
116 switch(signal->get_message()->get_flags())
118 case CAN_PROTOCOL_WITH_FD_FRAME:
119 message = new can_message_t(CANFD_MAX_DLEN,
120 signal->get_message()->get_id(),
123 signal->get_message()->get_flags(),
126 return build_frame(signal, value, message, factor, offset);
127 #ifdef USE_FEATURE_J1939
129 message = new j1939_message_t(signal->get_message()->get_length(),
133 signal->get_message()->get_id(),
135 return build_frame(signal, value, message, factor, offset);
138 message = new can_message_t(CAN_MAX_DLEN,
139 signal->get_message()->get_id(),
142 signal->get_message()->get_flags(),
145 return build_frame(signal, value, message, factor, offset);
147 message = new can_message_t(CAN_MAX_DLEN,
148 signal->get_message()->get_id(),
151 signal->get_message()->get_flags(),
154 return build_frame(signal, value, message, factor, offset);
159 /// @brief Encode a boolean into an integer, fit for a CAN signal bitfield.
161 /// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
162 /// bool*) that takes care of creating the DynamicField object for you with the
165 /// @param[in] signal - The CAN signal to encode this value for..
166 /// @param[in] value - The boolean value to encode
167 /// @param[out] send - An output argument that will be set to false if the value should
168 /// not be sent for any reason.
170 /// @return Returns the encoded integer. If 'send' is changed to false, the field could
171 /// not be encoded and the return value is undefined.
173 uint64_t encoder_t::encode_boolean(const signal_t& signal, bool value, bool* send)
175 return encode_number(signal, float(value), send);
177 /// @brief Encode a float into an integer, fit for a CAN signal's bitfield.
179 /// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
180 /// bool*) that takes care of creating the DynamicField object for you with the
183 /// @param[in] signal - The CAN signal to encode this value for.
184 /// @param[in] value - The float value to encode.
185 /// @param[out] send - This output argument will always be set to false, so the caller will
186 /// know not to publish this value to the pipeline.
188 /// @return Returns the encoded integer. If 'send' is changed to false, the field could
189 /// not be encoded and the return value is undefined.
191 uint64_t encoder_t::encode_number(const signal_t& signal, float value, bool* send)
193 return float_to_fixed_point(value, signal.get_factor(), signal.get_offset());
196 /// @brief Encode a string into an integer, fit for a CAN signal's bitfield.
198 /// Be aware that the behavior is undefined if there are multiple values assigned
199 /// to a single state. See https://github.com/openxc/vi-firmware/issues/185.
201 /// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
202 /// bool*) that takes care of creating the DynamicField object for you with the
203 /// string state value.
205 /// @param[in] signal - The details of the signal that contains the state mapping.
206 /// @param[in] value - The string state value to encode.
207 /// @param[out] send - An output argument that will be set to false if the value should
208 /// not be sent for any reason.
210 /// @return Returns the encoded integer. If 'send' is changed to false, the field could
211 /// not be encoded and the return value is undefined.
213 uint64_t encoder_t::encode_state(const signal_t& signal, const std::string& state, bool* send)
218 AFB_DEBUG("Can't write state of "" -- not sending");
223 uint64_t signal_state = signal.get_states(state);
224 if(signal_state != -1) {
225 value = signal_state;
227 AFB_DEBUG("Couldn't find a valid signal state for %s", state.c_str());
234 /// @brief Parse a signal from a CAN message and apply any required
235 /// transforations to get a human readable value.
237 /// If the signal_t has a non-NULL 'decoder' field, the raw CAN signal value
238 /// will be passed to the decoder before returning.
240 /// @param[in] signal - The details of the signal to decode and forward.
241 /// @param[in] value - The numerical value that will be converted to a boolean.
242 /// @param[out] send - An output parameter that will be flipped to false if the value could
245 /// @return The decoder returns an openxc_DynamicField, which may contain a number,
246 /// string or boolean. If 'send' is false, the return value is undefined.
248 uint64_t encoder_t::encode_DynamicField( signal_t& signal, const openxc_DynamicField& field, bool* send)
252 case openxc_DynamicField_Type_STRING:
253 value = encode_state(signal, field.string_value, send);
255 case openxc_DynamicField_Type_NUM:
256 value = encode_number(signal, (float)field.numeric_value, send);
258 case openxc_DynamicField_Type_BOOL:
259 value = encode_boolean(signal, field.boolean_value, send);
262 AFB_DEBUG("Dynamic field didn't have a value, can't encode");