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path: root/low-can-binding/utils/openxc-utils.cpp
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/*
 * Copyright (C) 2015, 2016 "IoT.bzh"
 * Author "Romain Forlot" <romain.forlot@iot.bzh>
 * Author "Loic Collignon" <loic.collignon@iot.bzh>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *	 http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "openxc-utils.hpp"
#include "converter.hpp"
#include "../binding/application.hpp"


///
/// @brief Build a specific VehicleMessage containing a DiagnosticResponse.
///
/// @param[in] request - Original request use to retrieve decoder and callback
/// @param[in] response - Response to the request that will be decoded if decoder set
///  and put into the DiagnosticResponse of the VehicleMessage.
/// @param[in] parsed_value - raw parsed value of the payload from CAN message
///
/// @return a vehicle message including simple message that will be convert into
/// a JSON object before being pushed to the subscribers
///
const openxc_VehicleMessage build_VehicleMessage(active_diagnostic_request_t* request, const DiagnosticResponse& response, float parsed_value)
{
	openxc_VehicleMessage message;
	::memset(&message, 0, sizeof(message));
	application_t& app = application_t::instance();

	message.has_type = true;
	message.type = openxc_VehicleMessage_Type::openxc_VehicleMessage_Type_DIAGNOSTIC;
	message.has_diagnostic_response = true;
	message.diagnostic_response.has_bus = true;
	message.diagnostic_response.bus = app.get_can_bus_manager().get_can_device_index(
																app.get_diagnostic_manager().get_bus_name());
	message.diagnostic_response.has_message_id = true;

	if(request->get_id() != OBD2_FUNCTIONAL_BROADCAST_ID)
	{
		message.diagnostic_response.message_id = response.arbitration_id
			- DIAGNOSTIC_RESPONSE_ARBITRATION_ID_OFFSET;
	}
	else
	{
		// must preserve responding arb ID for responses to functional broadcast
		// requests, as they are the actual module address and not just arb ID +
		// 8.
		message.diagnostic_response.message_id = response.arbitration_id;
	}

	message.diagnostic_response.has_mode = true;
	message.diagnostic_response.mode = response.mode;
	message.diagnostic_response.has_pid = response.has_pid;
	if(message.diagnostic_response.has_pid)
		message.diagnostic_response.pid = response.pid;
	message.diagnostic_response.has_success = true;
	message.diagnostic_response.success = response.success;
	message.diagnostic_response.has_negative_response_code = !response.success;
	message.diagnostic_response.negative_response_code =
			response.negative_response_code;

	if(response.payload_length > 0)
	{
		if(request->get_decoder() != nullptr)
		{
			message.diagnostic_response.has_value = true;
			message.diagnostic_response.value = parsed_value;
		}
		else
		{
			message.diagnostic_response.has_payload = true;
			::memcpy(message.diagnostic_response.payload.bytes, response.payload,
					response.payload_length);
			message.diagnostic_response.payload.size = response.payload_length;
		}
	}

	return message;
}
///
/// @brief Build a specific VehicleMessage containing a SimpleMessage with associated timestamp
///
/// @param[in] message - simple message to include into openxc_VehicleMessage
/// @param[in] timestamp - timestamp from ioctl when reading the socket
///
/// @return a vehicle message including simple message that will be convert into
/// a JSON object before being pushed to the subscribers
///
const openxc_VehicleMessage build_VehicleMessage(const openxc_SimpleMessage& message, uint64_t timestamp)
{
	openxc_VehicleMessage v;
	::memset(&v, 0, sizeof(v));

	v.has_type = true,
	v.type = openxc_VehicleMessage_Type::openxc_VehicleMessage_Type_SIMPLE;
	v.has_simple_message = true;
	v.simple_message =  message;
	v.has_timestamp = true;
	v.timestamp = timestamp;

	return v;
}

///
/// @brief Build a specific VehicleMessage containing a SimpleMessage.
///
/// @param[in] message - simple message to include into openxc_VehicleMessage
///
/// @return a vehicle message including simple message that will be convert into
/// a JSON object before being pushed to the subscribers
///
const openxc_VehicleMessage build_VehicleMessage(const openxc_SimpleMessage& message)
{
	openxc_VehicleMessage v;
	::memset(&v, 0, sizeof(v));

	v.has_type = true,
	v.type = openxc_VehicleMessage_Type::openxc_VehicleMessage_Type_SIMPLE;
	v.has_simple_message = true;
	v.simple_message =  message;
	v.has_timestamp = true;
	v.timestamp = system_time_us();

	return v;
}

///
/// @brief Build an empty VehicleMessage that isn't usable by at least the struct
///  is initialized for the most part and can be use to check a false return value.
///
/// @return A VehicleMessage with all boolean value to false.
///
openxc_VehicleMessage build_VehicleMessage()
{
	openxc_VehicleMessage v;

	::memset(&v, 0, sizeof(v));
	return v;
}

bool is_valid(const openxc_VehicleMessage& v)
{
	if (v.has_type == false &&
		v.has_can_message == false &&
		v.has_simple_message == false &&
		v.has_diagnostic_response == false &&
		v.has_control_command == false &&
		v.has_command_response == false &&
		v.has_timestamp == false)
			return false;
	return true;
}

///
/// @brief Build an openxc_SimpleMessage associating a name to an openxc_DynamicField
///
/// @param[in] name - const string reference name to assign to the created SimpleMessage
///  this will set has_name member to true and assign name to the name member. Maximum size for name is
///  set to 100 char.
/// @param[in] value - const reference with DynamicField to assign to SimpleMessage
///  value.
///
/// @return an openxc_SimpleMessage struct initialized with name and value provided.
///
const openxc_SimpleMessage build_SimpleMessage(const std::string& name, const openxc_DynamicField& value)
{
	openxc_SimpleMessage s;

	s.has_name = true;
	::strncpy(s.name, name.c_str(), 100);
	s.has_value = true;
	s.value = value;

	return s;
}

/// @brief Build an openxc_DynamicField with a json object
///
/// @param[in] value - const json_object pointer to assign to convert in an
///  openxc_DynamicField.
///
/// @return openxc_DynamicField initialized with a json object.
///
const openxc_DynamicField build_DynamicField(json_object* value)
{
	switch(json_object_get_type(value))
	{
		case json_type_string:
			return build_DynamicField(json_object_get_string(value));
		case json_type_double:
			return build_DynamicField(json_object_get_double(value));
		case json_type_int:
			return build_DynamicField(json_object_get_double(value));
		case json_type_boolean:
			return build_DynamicField((bool)json_object_get_boolean(value));
		default:
			openxc_DynamicField d;
			::memset(&d, 0, sizeof(openxc_DynamicField));
			return d;
	}
}

const openxc_DynamicField build_DynamicField(std::vector<uint8_t> &array)
{
	openxc_DynamicField d;
	d.has_type = true;
	d.type = openxc_DynamicField_Type_BYTES;

	d.has_string_value = false;
	d.has_numeric_value = false;
	d.has_boolean_value = false;
	d.has_bytes_value = true;


	size_t size = array.size();

	if(size > 2040)
	{
		AFB_ERROR("Error to generate array dynamic field, too large data");
		return d;
	}
	else
	{
		 d.length_array = (uint32_t) size;
	}


	for(int i=0;i<size;i++)
		d.bytes_value[i] = array[i];

	return d;
}


///
/// @brief Build an openxc_DynamicField with a string value
///
/// @param[in] value - const string reference value to assign to builded
///  openxc_DynamicField.
///
/// @return openxc_DynamicField initialized with a string value.
///
const openxc_DynamicField build_DynamicField(const char* value)
{
	openxc_DynamicField d;
	d.has_type = true;
	d.type = openxc_DynamicField_Type_STRING;

	d.has_string_value = true;
	d.has_numeric_value = false;
	d.has_boolean_value = false;
	d.has_bytes_value = false;
	::strncpy(d.string_value, value, 100);

	return d;
}

///
/// @brief Build an openxc_DynamicField with a string value
///
/// @param[in] value - const string reference value to assign to builded
///  openxc_DynamicField.
///
/// @return openxc_DynamicField initialized with a string value.
///
const openxc_DynamicField build_DynamicField(const std::string& value)
{
	openxc_DynamicField d;
	d.has_type = true;
	d.type = openxc_DynamicField_Type_STRING;

	d.has_string_value = true;
	d.has_numeric_value = false;
	d.has_boolean_value = false;
	d.has_bytes_value = false;
	::strncpy(d.string_value, value.c_str(), 100);

	return d;
}

///
/// @fn openxc_DynamicField build_DynamicField(double value);
///
/// @brief Build an openxc_DynamicField with a double value
///
/// @param[in] value - double value to assign to builded openxc_DynamicField.
///
/// @return openxc_DynamicField initialized with a double value.
///
const openxc_DynamicField build_DynamicField(double value)
{
	openxc_DynamicField d;
	d.has_type = true;
	d.type = openxc_DynamicField_Type_NUM;

	d.has_string_value = false;
	d.has_numeric_value = true;
	d.has_boolean_value = false;
	d.has_bytes_value = false;
	d.numeric_value = value;

	return d;
}

///
/// @brief Build an openxc_DynamicField with a boolean value
///
/// @param[in] value - boolean value to assign to builded openxc_DynamicField.
///
/// @return openxc_DynamicField initialized with a boolean value.
///
const openxc_DynamicField build_DynamicField(bool value)
{
	openxc_DynamicField d;
	d.has_type = true;
	d.type = openxc_DynamicField_Type_BOOL;

	d.has_string_value = false;
	d.has_numeric_value = false;
	d.has_boolean_value = true;
	d.has_bytes_value = false;
	d.boolean_value = value;


	return d;
}

int get_bool_from_DynamicField(const openxc_VehicleMessage& v_msg, bool* ret)
{
	if(v_msg.has_simple_message && v_msg.simple_message.has_value && v_msg.simple_message.value.has_boolean_value)
	{
		*ret = v_msg.simple_message.value.boolean_value;
		return 0;
	}

	return -1;
}

double get_numerical_from_DynamicField(const openxc_VehicleMessage& v_msg)
{
	return (v_msg.has_simple_message && v_msg.simple_message.has_value && v_msg.simple_message.value.has_numeric_value) ?
		v_msg.simple_message.value.numeric_value : -1.0;
}

const std::string get_string_from_DynamicField(const openxc_VehicleMessage& v_msg)
{
return (v_msg.has_simple_message && v_msg.simple_message.has_value && v_msg.simple_message.value.has_string_value) ?
		v_msg.simple_message.value.string_value : "";
}

///
/// @brief Extract the simple message value from an openxc_VehicleMessage
///  and return it. If there isn't SimpleMessage in the VehicleMessage then
///  returned value will be a SimpleMessage with all field set at false.
///  DynamicField from SimpleMessage will be boolean DynamicField set to false too.
///
/// @param[in] v_msg - const reference to openxc_VehicleMessage
///
/// @return A simpleMessage from the provided VehicleMessage.
///
const openxc_SimpleMessage get_simple_message(const openxc_VehicleMessage& v_msg)
{
	if (v_msg.has_simple_message)
		return v_msg.simple_message;

	openxc_SimpleMessage s_msg = { false, "", false, build_DynamicField(false), false, build_DynamicField(false)};
	return s_msg;
}

///
/// @brief Make a JSON object from a DynamicField
///
/// @param[in] field - openxc_DynamicField struct to convert into
///  a json object.
/// @param[out] value - pointer to the object to set up.
///
void jsonify_DynamicField(const openxc_DynamicField& field, json_object* value)
{
	if(field.has_numeric_value)
	{
		json_object_object_add(value, "value", json_object_new_double(field.numeric_value));
	}
	else if(field.has_boolean_value)
	{
		json_object_object_add(value, "value", json_object_new_boolean(field.boolean_value));
	}
	else if(field.has_string_value)
	{
		json_object_object_add(value, "value", json_object_new_string(field.string_value));
	}
	else if(field.has_bytes_value)
	{
		std::string s = converter_t::to_hex(field.bytes_value,field.length_array);

		json_object_object_add(value, "value", json_object_new_string(s.c_str()));
	}
}

///
/// @brief Make a JSON object from a SimpleMessage
///
/// @param[in] s_msg - const reference to an openxc_SimpleMessage
/// struct to convert into a json object.
/// @param[out] json - pointer with the DynamicField converted into json object
///
/// @return True if SimpleMessage has been transformed into json object
///  and false if not. In such case, a json object is returned { "error": "error msg"}
///
bool jsonify_simple(const openxc_SimpleMessage& s_msg, json_object* json)
{
	if(s_msg.has_name)
	{
		json_object_object_add(json, "name", json_object_new_string(s_msg.name));
		jsonify_DynamicField(s_msg.value, json);
		return true;
	}
	json_object_object_add(json, "error", json_object_new_string("openxc_SimpleMessage doesn't have name'"));
	return false;
}

///
/// @brief Make a JSON object from a VehicleMessage
///
/// @param[in] v_msg - const reference to an openxc_VehicleMessage
/// struct to convert into a json object.
/// @param[out] json - pointer with the DynamicField converted into json object
///
/// @return True if VehicleMessage has been transformed into json object
///  and false if not. In such case, a json object is returned { "error": "error msg"}
///
bool jsonify_vehicle(const openxc_VehicleMessage& v_msg, json_object* json)
{
	if(jsonify_simple(get_simple_message(v_msg), json))
	{
		if(v_msg.has_timestamp)
		{
			json_object_object_add(json, "timestamp", json_object_new_int64(v_msg.timestamp));
			return true;
		}
		return true;
	}
	json_object_object_add(json, "error", json_object_new_string("openxc_SimpleMessage doesn't have name'"));
	return false;
}
span class="p">; } } session_unlock(session); } } return now; } /** * Initialize the session manager with a 'max_session_count', * an initial common 'timeout' and an initial common token 'initok'. * * @param max_session_count maximum allowed session count in the same time * @param timeout the initial default timeout of sessions * @param initok the initial default token of sessions * */ int afb_session_init (int max_session_count, int timeout, const char *initok) { /* check parameters */ if (initok && strlen(initok) >= sizeof sessions.initok) { ERROR("initial token '%s' too long (max length %d)", initok, ((int)(sizeof sessions.initok)) - 1); errno = EINVAL; return -1; } /* init the sessionset (after cleanup) */ sessionset_lock(); sessionset_cleanup(1); sessions.max = max_session_count; sessions.timeout = timeout; if (initok == NULL) new_uuid(sessions.initok); else strcpy(sessions.initok, initok); sessionset_unlock(); return 0; } /** * Iterate the sessions and call 'callback' with * the 'closure' for each session. */ void afb_session_foreach(void (*callback)(void *closure, struct afb_session *session), void *closure) { struct afb_session *session; int idx; /* Loop on Sessions Table and remove anything that is older than timeout */ sessionset_lock(); for (idx = 0 ; idx < HEADCOUNT; idx++) { session = sessions.heads[idx]; while (session) { if (!session->closed) callback(closure, session); session = session->next; } } sessionset_unlock(); } /** * Cleanup the sessionset of its closed or expired sessions */ void afb_session_purge() { sessionset_lock(); sessionset_cleanup(0); sessionset_unlock(); } /** * @return the initial token set at initialization */ const char *afb_session_initial_token() { return sessions.initok; } /* Searchs the session of 'uuid' */ struct afb_session *afb_session_search (const char *uuid) { struct afb_session *session; sessionset_lock(); sessionset_cleanup(0); session = sessionset_search(uuid, pearson4(uuid)); session = afb_session_addref(session); sessionset_unlock(); return session; } /** * Creates a new session with 'timeout' */ struct afb_session *afb_session_create (int timeout) { return afb_session_get(NULL, timeout, NULL); } /** * Returns the timeout of 'session' in seconds */ int afb_session_timeout(struct afb_session *session) { int timeout; /* compute timeout */ timeout = session->timeout; if (timeout == AFB_SESSION_TIMEOUT_DEFAULT) timeout = sessions.timeout; if (timeout < 0) timeout = INT_MAX; return timeout; } /** * Returns the second remaining before expiration of 'session' */ int afb_session_what_remains(struct afb_session *session) { return (int)(session->expiration - NOW); } /* This function will return exiting session or newly created session */ struct afb_session *afb_session_get (const char *uuid, int timeout, int *created) { char _uuid_[SIZEUUID]; uint8_t hashidx; struct afb_session *session; time_t now; int c; /* cleaning */ sessionset_lock(); now = sessionset_cleanup(0); /* search for an existing one not too old */ if (!uuid) { hashidx = sessionset_make_uuid(_uuid_); uuid = _uuid_; } else { hashidx = pearson4(uuid); session = sessionset_search(uuid, hashidx); if (session) { /* session found */ afb_session_addref(session); c = 0; goto end; } } /* create the session */ session = session_add(uuid, timeout, now, hashidx); c = 1; end: sessionset_unlock(); if (created) *created = c; return session; } /* increase the use count on 'session' (can be NULL) */ struct afb_session *afb_session_addref(struct afb_session *session) { if (session != NULL) { #if WITH_AFB_HOOK afb_hook_session_addref(session); #endif session_lock(session); session->refcount++; session_unlock(session); } return session; } /* decrease the use count of 'session' (can be NULL) */ void afb_session_unref(struct afb_session *session) { if (session == NULL) return; #if WITH_AFB_HOOK afb_hook_session_unref(session); #endif session_lock(session); if (!--session->refcount) { if (session->autoclose) session_close(session); if (session->notinset) { session_destroy(session); return; } } session_unlock(session); } /* close 'session' */ void afb_session_close (struct afb_session *session) { session_lock(session); session_close(session); session_unlock(session); } /** * Set the 'autoclose' flag of the 'session' * * A session whose autoclose flag is true will close as * soon as it is no more referenced. * * @param session the session to set * @param autoclose the value to set */ void afb_session_set_autoclose(struct afb_session *session, int autoclose) { session->autoclose = !!autoclose; } /* is 'session' closed? */ int afb_session_is_closed (struct afb_session *session) { return session->closed; } /* * check whether the token of 'session' is 'token' * return 1 if true or 0 otherwise */ int afb_session_check_token (struct afb_session *session, const char *token) { int r; session_lock(session); r = !session->closed && session->expiration >= NOW && !(session->token[0] && strcmp (token, session->token)); session_unlock(session); return r; } /* generate a new token and update client context */ void afb_session_new_token (struct afb_session *session) { session_lock(session); new_uuid(session->token); session_update_expiration(session, NOW); #if WITH_AFB_HOOK afb_hook_session_renew(session); #endif session_unlock(session); } /* Returns the uuid of 'session' */ const char *afb_session_uuid (struct afb_session *session) { return session->uuid; } /* Returns the token of 'session' */ const char *afb_session_token (struct afb_session *session) { return session->token; } /** * Get the index of the 'key' in the cookies array. * @param key the key to scan * @return the index of the list for key within cookies */ static int cookeyidx(const void *key) { intptr_t x = (intptr_t)key; unsigned r = (unsigned)((x >> 5) ^ (x >> 15)); return r & COOKIEMASK; } /** * Set, get, replace, remove a cookie of 'key' for the 'session' * * The behaviour of this function depends on its parameters: * * @param session the session * @param key the key of the cookie * @param makecb the creation function or NULL * @param freecb the release function or NULL * @param closure an argument for makecb or the value if makecb==NULL * @param replace a boolean enforcing replecement of the previous value * * @return the value of the cookie * * The 'key' is a pointer and compared as pointers. * * For getting the current value of the cookie: * * afb_session_cookie(session, key, NULL, NULL, NULL, 0) * * For storing the value of the cookie * * afb_session_cookie(session, key, NULL, NULL, value, 1) */ void *afb_session_cookie(struct afb_session *session, const void *key, void *(*makecb)(void *closure), void (*freecb)(void *item), void *closure, int replace) { int idx; void *value; struct cookie *cookie, **prv; /* get key hashed index */ idx = cookeyidx(key); /* lock session and search for the cookie of 'key' */ session_lock(session); prv = &session->cookies[idx]; for (;;) { cookie = *prv; if (!cookie) { /* 'key' not found, create value using 'closure' and 'makecb' */ value = makecb ? makecb(closure) : closure; /* store the the only if it has some meaning */ if (replace || makecb || freecb) { cookie = malloc(sizeof *cookie); if (!cookie) { errno = ENOMEM; /* calling freecb if there is no makecb may have issue */ if (makecb && freecb) freecb(value); value = NULL; } else { cookie->key = key; cookie->value = value; cookie->freecb = freecb; cookie->next = NULL; *prv = cookie; } } break; } else if (cookie->key == key) { /* cookie of key found */ if (!replace) /* not replacing, get the value */ value = cookie->value; else { /* create value using 'closure' and 'makecb' */ value = makecb ? makecb(closure) : closure; /* free previous value is needed */ if (cookie->value != value && cookie->freecb) cookie->freecb(cookie->value); /* if both value and freecb are NULL drop the cookie */ if (!value && !freecb) { *prv = cookie->next; free(cookie); } else { /* store the value and its releaser */ cookie->value = value; cookie->freecb = freecb; } } break; } else { prv = &(cookie->next); } } /* unlock the session and return the value */ session_unlock(session); return value; } /** * Get the cookie of 'key' in the 'session'. * * @param session the session to search in * @param key the key of the data to retrieve * * @return the data staored for the key or NULL if the key isn't found */ void *afb_session_get_cookie(struct afb_session *session, const void *key) { return afb_session_cookie(session, key, NULL, NULL, NULL, 0); } /** * Set the cookie of 'key' in the 'session' to the 'value' that can be * cleaned using 'freecb' (if not null). * * @param session the session to set * @param key the key of the data to store * @param value the value to store at key * @param freecb a function to use when the cookie value is to remove (or null) * * @return 0 in case of success or -1 in case of error */ int afb_session_set_cookie(struct afb_session *session, const void *key, void *value, void (*freecb)(void*)) { return -(value != afb_session_cookie(session, key, NULL, freecb, value, 1)); } /** * Set the language attached to the session * * @param session the session to set * @param lang the language specifiction to set to session * * @return 0 in case of success or -1 in case of error */ int afb_session_set_language(struct afb_session *session, const char *lang) { char *oldl, *newl; newl = strdup(lang); if (newl == NULL) return -1; oldl = session->lang; session->lang = newl; free(oldl); return 0; } /** * Get the language attached to the session * * @param session the session to query * @param lang a default language specifiction * * @return the langauage specification to use for session */ const char *afb_session_get_language(struct afb_session *session, const char *lang) { return session->lang ?: lang; }