Diff: src/CayenneUtils/CayenneUtils.c

Revision:

0:09ef59d2d0f7

Child:

6:82e142a864ad

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/CayenneUtils/CayenneUtils.c	Fri Oct 07 17:21:45 2016 +0000
@@ -0,0 +1,537 @@
+/*
+The MIT License(MIT)
+
+Cayenne MQTT Client Library
+Copyright (c) 2016 myDevices
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+documentation files(the "Software"), to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense, and / or sell copies of the Software,
+and to permit persons to whom the Software is furnished to do so, subject to the following conditions :
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+*/
+
+#include <stdlib.h> 
+#include <string.h> 
+#include "CayenneUtils.h"
+
+#ifdef DIGITAL_AND_ANALOG_SUPPORT
+	#ifdef PARSE_INFO_PAYLOADS
+		#define PARSE_TOPICS_COUNT 13
+	#else
+		#define PARSE_TOPICS_COUNT 6
+	#endif
+#else
+	#ifdef PARSE_INFO_PAYLOADS
+		#define PARSE_TOPICS_COUNT 7
+	#else
+		#define PARSE_TOPICS_COUNT 2
+	#endif
+#endif
+
+#define THINGS_STRING CAYENNE_PSTR("/things/")
+
+typedef struct TopicChannel
+{
+	CayenneTopic topic;
+	unsigned int channel;
+} TopicChannel;
+
+/**
+* Build a specified topic string.
+* @param[out] topic Returned topic string
+* @param[in] length CayenneTopic buffer length
+* @param[in] username Cayenne username
+* @param[in] clientID Cayennne client ID
+* @param[in] suffix The topic suffix
+* @return CAYENNE_SUCCESS if topic string was created, error code otherwise
+*/
+int buildTopic(char* topic, size_t length, const char* username, const char* clientID, const char* suffix) {
+	size_t topicLength = 0;
+	if (!topic || !username || !clientID || !suffix)
+		return CAYENNE_FAILURE;
+	topicLength = strlen(username) + strlen(clientID) + strlen(suffix) + 11;
+	if (topicLength > length)
+		return CAYENNE_BUFFER_OVERFLOW;
+
+	topic[0] = '\0';
+	strcat(topic, CAYENNE_VERSION);
+	strcat(topic, "/");
+	strcat(topic, username);
+	CAYENNE_STRCAT(topic, THINGS_STRING);
+	strcat(topic, clientID);
+	strcat(topic, "/");
+	strcat(topic, suffix);
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Build a specified topic suffix string.
+* @param[out] suffix Returned suffix string
+* @param[in] length Suffix buffer length
+* @param[in] topic Cayenne topic
+* @param[in] channel The topic channel, CAYENNE_NO_CHANNEL for none, CAYENNE_ALL_CHANNELS for all
+* @return CAYENNE_SUCCESS if suffix string was created, error code otherwise
+*/
+int buildSuffix(char* suffix, size_t length, const CayenneTopic topic, unsigned int channel) {
+	char* topicString = NULL;
+	if (!suffix)
+		return CAYENNE_FAILURE;
+	switch (topic)
+	{
+	case COMMAND_TOPIC:
+		topicString = COMMAND_STRING;
+		break;
+	case CONFIG_TOPIC:
+		topicString = CONFIG_STRING;
+		break;
+	case DATA_TOPIC:
+		topicString = DATA_STRING;
+		break;
+	case RESPONSE_TOPIC:
+		topicString = RESPONSE_STRING;
+		break;
+	case SYS_MODEL_TOPIC:
+		topicString = SYS_MODEL_STRING;
+		break;
+	case SYS_VERSION_TOPIC:
+		topicString = SYS_VERSION_STRING;
+		break;
+	case SYS_CPU_MODEL_TOPIC:
+		topicString = SYS_CPU_MODEL_STRING;
+		break;
+	case SYS_CPU_SPEED_TOPIC:
+		topicString = SYS_CPU_SPEED_STRING;
+		break;
+#ifdef DIGITAL_AND_ANALOG_SUPPORT
+	case DIGITAL_TOPIC:
+		topicString = DIGITAL_STRING;
+		break;
+	case DIGITAL_COMMAND_TOPIC:
+		topicString = DIGITAL_COMMAND_STRING;
+		break;
+	case DIGITAL_CONFIG_TOPIC:
+		topicString = DIGITAL_CONFIG_STRING;
+		break;
+	case ANALOG_TOPIC:
+		topicString = ANALOG_STRING;
+		break;
+	case ANALOG_COMMAND_TOPIC:
+		topicString = ANALOG_COMMAND_STRING;
+		break;
+	case ANALOG_CONFIG_TOPIC:
+		topicString = ANALOG_CONFIG_STRING;
+		break;
+#endif
+	default:
+		return CAYENNE_FAILURE;
+	}
+
+	if (!topicString)
+		return CAYENNE_FAILURE;
+	if (CAYENNE_STRLEN(topicString) >= length)
+		return CAYENNE_BUFFER_OVERFLOW;
+
+	suffix[0] = '\0';
+	CAYENNE_STRCAT(suffix, topicString);
+	if (channel != CAYENNE_NO_CHANNEL) {
+		strcat(suffix, "/");
+		if (channel == CAYENNE_ALL_CHANNELS) {
+			strcat(suffix, "+");
+		}
+		else {
+#if defined(__AVR__) || defined (ARDUINO_ARCH_ARC32)
+			itoa(channel, &suffix[strlen(suffix)], 10);
+#else
+			snprintf(&suffix[strlen(suffix)], length - strlen(suffix), "%u", channel);
+#endif
+		}
+	}
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Check if topic matches.
+* @param[in] filter Filter to check topic against
+* @param[in] topicName CayenneTopic name
+* @param[in] topicNameLen CayenneTopic name length
+* return true if topic matches, false otherwise
+*/
+int topicMatches(char* filter, char* topicName, unsigned int topicNameLen)
+{
+	char* curf = filter;
+	char* curn = topicName;
+	char* curn_end = topicName + topicNameLen;
+
+	while (*curf && curn < curn_end)
+	{
+		if (*curn == '/' && *curf != '/')
+			break;
+		if (*curf != '+' && *curf != '#' && *curf != *curn)
+			break;
+		if (*curf == '+')
+		{   // skip until we meet the next separator, or end of string
+			char* nextpos = curn + 1;
+			while (nextpos < curn_end && *nextpos != '/')
+				nextpos = ++curn + 1;
+		}
+		else if (*curf == '#')
+			curn = curn_end - 1;    // skip until end of string
+		curf++;
+		curn++;
+	};
+
+	return ((curn == curn_end) && (*curf == '\0'));
+}
+
+/**
+* Get the count of values in a message.
+* @param[out] count Returned number of values found in message
+* @param[in] payload Payload string, must be null terminated
+* @param[in] token Character token for splitting "unit=value" payloads, 0 to just parse first comma delimited value
+* @return CAYENNE_SUCCESS if value count succeeded, error code otherwise
+*/
+int getValueCount(size_t* count, char* payload, char token) {
+	char* index = payload;
+	size_t unitCount = 0;
+	size_t valueCount = 0;
+	int countingValues = 0;
+
+	if (token == 0) {
+		//Currently there can only be one value in payload if this isn't a "unit=value" payload.
+		*count = 1;
+		return CAYENNE_SUCCESS;
+	}
+
+	*count = 0;
+	while (*index && index != '\0') {
+		if ((*index == ',') || (*index == token)) {
+			if (*index == ',') {
+				if (countingValues) {
+					valueCount++;
+				}
+				else {
+					unitCount++;
+				}
+			}
+			else if (*index == token) {
+				countingValues = 1;
+				valueCount++;
+			}
+		}
+		index++;
+	}
+	
+	if (countingValues) {
+		if ((valueCount != unitCount) && !(unitCount == 0 && valueCount == 1)) {
+			return CAYENNE_FAILURE;
+		}
+	}
+	else {
+		valueCount = 1;
+	}
+	*count = valueCount;
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Parse a null terminated payload string in place. This may modify the payload string.
+* @param[out] values Returned payload data unit & value array
+* @param[in,out] valuesSize Size of values array, returns the count of values in the array
+* @param[out] type Returned type, NULL if there is none
+* @param[in] payload Payload string, must be null terminated
+* @param[in] token Character token for splitting "unit=value" payloads, 0 to just parse first comma delimited value
+* @return CAYENNE_SUCCESS if value and id were parsed, error code otherwise
+*/
+int parsePayload(CayenneValuePair* values, size_t* valuesSize, const char** type, char* payload, char token) {
+	char* index = payload;
+	size_t count = 0;
+	int parsingValues = 0;
+	size_t valueIndex = 0;
+#ifdef PARSE_INFO_PAYLOADS
+	int result = getValueCount(&count, payload, token);
+	if (result != CAYENNE_SUCCESS) {
+		*valuesSize = 0;
+		return result;
+	}
+#else
+	count = 1;
+#endif
+
+	if(token == 0)
+		parsingValues = 1; //Don't need to parse units if there is no unit/value separator
+
+	values[0].value = NULL;
+	values[0].unit = NULL;
+	*type = NULL;
+	while (*index && index != '\0') {
+		if ((*index == ',') || (*index == token))	{
+			if (*index == ',') {
+				*type = payload;
+				if (valueIndex < *valuesSize) {
+					if (parsingValues) {
+						values[valueIndex].value = index + 1;
+					}
+					else {
+						values[valueIndex].unit = index + 1;
+					}
+				}
+				*index = '\0';
+				valueIndex++;
+				if (token == 0)
+					break;
+			}
+			else if (*index == token && !parsingValues) {
+				parsingValues = 1;
+				valueIndex = 0;
+				*type = payload;
+				values[valueIndex].value = index + 1;
+				*index = '\0';
+				valueIndex++;
+				if (count == valueIndex)
+					break;
+			}
+		}
+		index++;
+	};
+	*valuesSize = count;
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Build a specified topic string.
+* @param[out] topicName Returned topic string
+* @param[in] length CayenneTopic buffer length
+* @param[in] username Cayenne username
+* @param[in] clientID Cayennne client ID
+* @param[in] topic Cayenne topic
+* @param[in] channel The topic channel, CAYENNE_NO_CHANNEL for none, CAYENNE_ALL_CHANNELS for all
+* @return CAYENNE_SUCCESS if topic string was created, error code otherwise
+*/
+int CayenneBuildTopic(char* topicName, size_t length, const char* username, const char* clientID, CayenneTopic topic, unsigned int channel) {
+	char channelSuffix[20] = {0};
+	int result = buildSuffix(channelSuffix, sizeof(channelSuffix), topic, channel);
+	if (result != CAYENNE_SUCCESS)
+		return result;
+	return buildTopic(topicName, length, username, clientID, channelSuffix);
+}
+
+/**
+* Build a specified data payload.
+* @param[out] payload Returned payload
+* @param[in,out] length Payload buffer length
+* @param[in] type Optional type to use for type,unit=value payload, can be NULL
+* @param[in] values Unit/value array
+* @param[in] valueCount Number of values
+* @return CAYENNE_SUCCESS if topic string was created, error code otherwise
+*/
+int CayenneBuildDataPayload(char* payload, size_t* length, const char* type, const CayenneValuePair* values, size_t valueCount) {
+	int i;
+	size_t payloadLength = 0;
+	for (i = 0; i < valueCount; ++i) {
+		payloadLength += values[i].unit ? strlen(values[i].unit) + 1 : 0;
+		payloadLength += values[i].value ? strlen(values[i].value) + 1 : 0;
+	}
+	payloadLength += type ? strlen(type) + 1 : 0;
+	//If payload can't fit the payload plus a terminating null byte return.
+	if (payloadLength > *length) {
+		return CAYENNE_BUFFER_OVERFLOW;
+	}
+
+	payload[0] = '\0';
+	if (type) {
+		strcat(payload, type);
+	}
+	for (i = 0; i < valueCount && values[i].unit; ++i) {
+		if(payload[0] != '\0')
+			strcat(payload, ",");
+		strcat(payload, values[i].unit);
+	}
+	if (payload[0] != '\0' && valueCount > 0 && values[0].value)
+		strcat(payload, "=");
+	for (i = 0; i < valueCount && values[i].value; ++i) {
+		strcat(payload, values[i].value);
+		if(i + 1 < valueCount)
+			strcat(payload, ",");
+	}
+	*length = --payloadLength; //Subtract terminating null 
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Build a specified response payload.
+* @param[out] payload Returned payload
+* @param[in,out] length Payload buffer length
+* @param[in] id ID of message the response is for
+* @param[in] error Optional error message, NULL for success
+* @return CAYENNE_SUCCESS if payload string was created, error code otherwise
+*/
+int CayenneBuildResponsePayload(char* payload, size_t* length, const char* id, const char* error) {
+	CayenneValuePair values[1];
+	values[0].unit = id;
+	values[0].value = error;
+	if (error) {
+		return CayenneBuildDataPayload(payload, length, "error", values, 1);
+	}
+	return CayenneBuildDataPayload(payload, length, "ok", values, 1);
+}
+
+/**
+* Parse a topic string in place. This may modify the topic string.
+* @param[out] topic Returned Cayenne topic
+* @param[out] channel Returned channel, CAYENNE_NO_CHANNEL if there is none
+* @param[out] clientID Returned client ID
+* @param[in] username Cayenne username
+* @param[in] topicName Topic name string
+* @param[in] length Topic name string length
+* @return CAYENNE_SUCCESS if topic was parsed, error code otherwise
+*/
+int CayenneParseTopic(CayenneTopic* topic, unsigned int* channel, const char** clientID, const char* username, char* topicName, unsigned int length) {
+	char* index = NULL;
+	int i = 0;
+	TopicChannel parseTopics[PARSE_TOPICS_COUNT] = { { COMMAND_TOPIC, CAYENNE_ALL_CHANNELS },{ CONFIG_TOPIC, CAYENNE_ALL_CHANNELS },
+#ifdef DIGITAL_AND_ANALOG_SUPPORT
+		{ ANALOG_COMMAND_TOPIC, CAYENNE_ALL_CHANNELS },{ ANALOG_CONFIG_TOPIC, CAYENNE_ALL_CHANNELS },{ DIGITAL_COMMAND_TOPIC, CAYENNE_ALL_CHANNELS },{ DIGITAL_CONFIG_TOPIC, CAYENNE_ALL_CHANNELS },
+#ifdef PARSE_INFO_PAYLOADS
+		{ DIGITAL_TOPIC, CAYENNE_ALL_CHANNELS },{ ANALOG_TOPIC, CAYENNE_ALL_CHANNELS },
+#endif
+#endif
+#ifdef PARSE_INFO_PAYLOADS
+		{ DATA_TOPIC, CAYENNE_ALL_CHANNELS },{ SYS_MODEL_TOPIC, CAYENNE_NO_CHANNEL },{ SYS_VERSION_TOPIC, CAYENNE_NO_CHANNEL },{ SYS_CPU_MODEL_TOPIC, CAYENNE_NO_CHANNEL },{ SYS_CPU_SPEED_TOPIC, CAYENNE_NO_CHANNEL }
+#endif
+	};
+
+	if (!topic || !channel || !topicName)
+	{
+		return CAYENNE_FAILURE;
+	}
+	if (length > CAYENNE_MAX_MESSAGE_SIZE)
+	{
+		return CAYENNE_BUFFER_OVERFLOW;
+	}
+	if (strncmp(CAYENNE_VERSION, topicName, strlen(CAYENNE_VERSION)) != 0)
+		return CAYENNE_FAILURE;
+	index = topicName + strlen(CAYENNE_VERSION) + 1;
+	if (strncmp(username, index, strlen(username)) != 0)
+		return CAYENNE_FAILURE;
+	index += strlen(username);
+	if (CAYENNE_STRNCMP(index, THINGS_STRING, CAYENNE_STRLEN(THINGS_STRING)) != 0)
+		return CAYENNE_FAILURE;
+	index += CAYENNE_STRLEN(THINGS_STRING);
+	char* deviceIDEnd = strchr(index, '/');
+	if (!deviceIDEnd)
+		return CAYENNE_FAILURE;
+	*clientID = index;
+	*deviceIDEnd = '\0';
+
+	index = deviceIDEnd + 1;
+	*topic = UNDEFINED_TOPIC;
+	*channel = CAYENNE_NO_CHANNEL;
+	length -= (index - topicName);
+	for (i = 0; i < PARSE_TOPICS_COUNT; ++i)
+	{
+		char channelSuffix[32] = { 0 };
+		if (buildSuffix(channelSuffix, sizeof(channelSuffix), parseTopics[i].topic, parseTopics[i].channel) == CAYENNE_SUCCESS && topicMatches(channelSuffix, index, length)) {
+			*topic = parseTopics[i].topic;
+			break;
+		}
+	}
+
+	if (*topic == UNDEFINED_TOPIC)
+		return CAYENNE_FAILURE;
+
+	if (parseTopics[i].channel != CAYENNE_NO_CHANNEL) {
+		if (length == 0 || length > 31)
+			return CAYENNE_FAILURE;
+		char* channelIndex = NULL;
+		char buffer[32] = { 0 };
+		memcpy(buffer, index, length);
+		buffer[length] = '\0';
+		channelIndex = strrchr(buffer, '/');
+		if (channelIndex && ++channelIndex) {
+			char* indexEnd = NULL;
+			unsigned int channelNumber = strtoul(channelIndex, &indexEnd, 10);
+			if (indexEnd && *indexEnd == '\0') {
+				if (((channelNumber != 0) && (*channelIndex != '0')) || ((channelNumber == 0) && (*channelIndex == '0') && (channelIndex + 1 == indexEnd))) {
+					*channel = channelNumber;
+				}
+			}
+		}
+	}
+
+	return CAYENNE_SUCCESS;
+}
+
+/**
+* Parse a null terminated payload in place. This may modify the payload string.
+* @param[out] values Returned payload data unit & value array
+* @param[in,out] valuesSize Size of values array, returns the count of values in the array
+* @param[out] type Returned type, NULL if there is none
+* @param[out] id Returned message id, empty string if there is none
+* @param[in] topic Cayenne topic
+* @param[in] payload Payload string, must be null terminated.
+* @return CAYENNE_SUCCESS if topic string was created, error code otherwise
+*/
+int CayenneParsePayload(CayenneValuePair* values, size_t* valuesSize, const char** type, const char** id, CayenneTopic topic, char* payload) {
+	int i;
+	if (!payload || !valuesSize || *valuesSize == 0)
+		return CAYENNE_FAILURE;
+
+	*type = NULL;
+	*id = NULL;
+	for(i = 0; i < *valuesSize; i++) {
+		values[i].unit = NULL;
+		values[i].value = NULL;
+	}
+	switch (topic)
+	{
+#ifdef PARSE_INFO_PAYLOADS
+	case DATA_TOPIC:
+		parsePayload(values, valuesSize, type, payload, '=');
+		if (!values[0].value)
+			return CAYENNE_FAILURE;
+		break;
+#endif
+#ifdef DIGITAL_AND_ANALOG_SUPPORT
+#ifdef PARSE_INFO_PAYLOADS
+	case ANALOG_TOPIC:
+		parsePayload(values, valuesSize, type, payload, 0);
+		values[0].unit = values[0].value; //Use unit to store resolution
+		values[0].value = *type;
+		*type = NULL; 
+		if (!values[0].value)
+			return CAYENNE_FAILURE;
+		break;
+#endif
+	case DIGITAL_COMMAND_TOPIC:
+	case ANALOG_COMMAND_TOPIC:
+#endif
+	case COMMAND_TOPIC:
+		parsePayload(values, valuesSize, type, payload, 0);
+		*id = *type;
+		*type = NULL;
+		if (!values[0].value)
+			return CAYENNE_FAILURE;
+		break;
+	default:
+		break;
+	}
+
+	if (!values[0].value) {
+		values[0].value = payload;
+		values[0].unit = NULL;
+		*type = NULL;
+		*id = NULL;
+		*valuesSize = 1;
+	}
+
+	return CAYENNE_SUCCESS;
+}
+
+
+