added polling by priority

src/lib/ebus/message.cpp

@@ -36,7 +36,7 @@ Message::Message(const string clazz, const string name, const bool isSet,
 		  m_isPassive(isPassive), m_comment(comment),
 		  m_srcAddress(srcAddress), m_dstAddress(dstAddress),
 		  m_id(id), m_data(data), m_pollPriority(pollPriority),
-		  m_lastUpdateTime(0)
+		  m_lastUpdateTime(0), m_pollCount(0), m_lastPollTime(0)
 {
 	int exp = 7;
 	unsigned long long key = (unsigned long long)(id.size()-2) << (8 * exp + 5);
@@ -269,7 +269,7 @@ result_t Message::prepareMaster(const unsigned char srcAddress, SymbolString& ma
 	result = m_data->write(input, pt_masterData, master, m_id.size() - 2, separator);
 	if (result != RESULT_OK)
 		return result;
-	masterData = SymbolString(master);
+	masterData = SymbolString(master, true);
 	return result;
 }
 
@@ -298,6 +298,18 @@ result_t Message::decode(const PartType partType, SymbolString& data,
 	return RESULT_OK;
 }
 
+bool Message::isLessPollWeight(Message* other) {
+	if (m_pollPriority * m_pollCount < other->m_pollPriority * other->m_pollCount)
+		return true;
+	if (m_pollPriority < other->m_pollPriority)
+		return true;
+	if (m_lastPollTime < other->m_lastPollTime)
+		return true;
+
+	return false;
+}
+
+
 result_t MessageMap::add(Message* message)
 {
 	unsigned long long pkey = message->getKey();
@@ -318,6 +330,7 @@ result_t MessageMap::add(Message* message)
 	}
 
 	m_messagesByName[key] = message;
+	m_messageCount++;
 
 	key = string(isPassive ? "-P;" : (isSet ? "-W;" : "-R;")) + name; // also store without class
 	m_messagesByName[key] = message; // last key without class overrides previous
@@ -331,7 +344,8 @@ result_t MessageMap::add(Message* message)
 		m_passiveMessagesByKey[pkey] = message;
 	}
 
-	//m_pollMessages.push()
+	if (message->getPollPriority() > 0)
+		m_pollMessages.push(message);
 
 	return RESULT_OK;
 }
@@ -418,12 +432,34 @@ Message* MessageMap::find(SymbolString& master)
 
 void MessageMap::clear()
 {
+	// clear poll messages
+	while (m_pollMessages.empty() == false) {
+		m_pollMessages.top();
+		m_pollMessages.pop();
+	}
+	// free message instances
 	for (map<string, Message*>::iterator it=m_messagesByName.begin(); it!=m_messagesByName.end(); it++) {
 		if (it->first[0] != '-') // avoid double free
 			delete it->second;
 		it->second = NULL;
 	}
+	// clear messages by name
+	m_messageCount = 0;
 	m_messagesByName.clear();
+	// clear messages by key
 	m_passiveMessagesByKey.clear();
+	m_minIdLength = 4;
 	m_maxIdLength = 0;
 }
+
+Message* MessageMap::getNextPoll()
+{
+	if (m_pollMessages.empty() == true)
+		return NULL;
+	Message* ret = m_pollMessages.top();
+	m_pollMessages.pop();
+	ret->m_pollCount++;
+	time(&(ret->m_lastPollTime));
+	m_pollMessages.push(ret); // re-insert at new position
+	return ret;
+}

src/lib/ebus/message.h

@@ -29,11 +29,14 @@
 
 using namespace std;
 
+class MessageMap;
+
 /**
  * @brief Defines parameters of a message sent or received on the bus.
  */
 class Message
 {
+	friend class MessageMap;
 public:
 
 	/**
@@ -151,11 +154,24 @@ public:
 	string getLastValue() { return m_lastValue; }
 
 	/**
-	 * @brief Get the system time when @a m_lastValue was updated.
+	 * @brief Get the time when @a m_lastValue was updated.
-	 * @return the system time when @a m_lastValue was updated, or 0 if this message was not decoded yet.
+	 * @return the time when @a m_lastValue was updated, or 0 if this message was not decoded yet.
 	 */
 	time_t getLastUpdateTime() { return m_lastUpdateTime; }
 
+	/**
+	 * @brief Get the time when this message was last polled for.
+	 * @return the time when this message was last polled for, or 0 for never.
+	 */
+	time_t getLastPollTime() { return m_lastPollTime; }
+
+	/**
+	 * @brief Return whether this @a Message needs to be polled before the other one.
+	 * @param other the other @a Message to compare with.
+	 * @return true if this @a Message needs to be polled before the other one.
+	 */
+	bool isLessPollWeight(Message* other);
+
 private:
 
 	 /** the optional device class. */
@@ -183,10 +199,24 @@ private:
 	const unsigned char m_pollPriority;
 	/** the last decoded value. */
 	string m_lastValue;
-	/** the system time when @a m_lastValue was updated. */
+	/** the system time when @a m_lastValue was updated, 0 for never. */
 	time_t m_lastUpdateTime;
+	/** the number of times this messages was already polled for. */
+	unsigned int m_pollCount;
+	/** the system time when this message was last polled for, 0 for never. */
+	time_t m_lastPollTime;
+
 };
 
+
+/**
+ * @brief A function that compares the poll priority of two @a Message instances.
+ */
+struct compareMessagePriority : binary_function <Message*,Message*,bool> {
+	bool operator() (Message* x, Message* y) const { return x->isLessPollWeight(y) == false; };
+};
+
+
 /**
  * @brief Holds a map of all known @a Message instances.
  */
@@ -197,7 +227,7 @@ public:
 	/**
 	 * @brief Construct a new instance.
 	 */
-	MessageMap() : FileReader(true), m_minIdLength(4), m_maxIdLength(0) {}
+	MessageMap() : FileReader(true), m_minIdLength(4), m_maxIdLength(0), m_messageCount(0) {}
 	/**
 	 * @brief Destructor.
 	 */
@@ -232,6 +262,23 @@ public:
 	 * @brief Removes all @a Message instances.
 	 */
 	void clear();
+	/**
+	 * @brief Get the number of stored @a Message instances.
+	 * @param passiveOnly true to count only passive messages, false to count all messages.
+	 * @return the the number of stored @a Message instances.
+	 */
+	int size(const bool passiveOnly=false) { return passiveOnly ? m_passiveMessagesByKey.size() : m_messageCount; }
+	/**
+	 * @brief Get the number of stored @a Message instances with a poll priority.
+	 * @return the the number of stored @a Message instances with a poll priority.
+	 */
+	int sizePoll() { return m_pollMessages.size(); }
+	/**
+	 * @brief Get the next @a Message to poll.
+	 * @return the next @a Message to poll, or NULL.
+	 * Note: the caller may not free the returned instance.
+	 */
+	Message* getNextPoll();
 
 private:
 
@@ -241,12 +288,18 @@ private:
 	/** the maximum ID length used by any of the known @a Message instances. */
 	unsigned char m_maxIdLength;
 
+	/** the number of distinct @a Message instances stored in @a m_messagesByName. */
+	int m_messageCount;
+
 	/** the known @a Message instances by class and name. */
 	map<string, Message*> m_messagesByName;
 
 	/** the known passive @a Message instances by key. */
 	map<unsigned long long, Message*> m_passiveMessagesByKey;
 
+	/** the known @a Message instances to poll, by priority. */
+	priority_queue<Message*, vector<Message*>, compareMessagePriority> m_pollMessages;
+
 };
 
 #endif // LIBEBUS_MESSAGE_H_