Keystone Developer
Example project to publish messages to a MQTT-SN broker using the u-blox SARA-N200 NB-IoT modem
Dependencies: MQTTSNPacket X-NUCLEO-SARA-N200
Diff: MQTTSNClient.h
- Revision:
- 1:70b751b7a189
- Child:
- 7:ab32680de141
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTSNClient.h Mon Aug 20 16:42:45 2018 +0200
@@ -0,0 +1,915 @@
+/*******************************************************************************
+ * Copyright (c) 2014, 2015 IBM Corp.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * and Eclipse Distribution License v1.0 which accompany this distribution.
+ *
+ * The Eclipse Public License is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * and the Eclipse Distribution License is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * Contributors:
+ * Ian Craggs - initial API and implementation and/or initial documentation
+ *******************************************************************************/
+
+#if !defined(MQTTSNCLIENT_H)
+#define MQTTSNCLIENT_H
+
+#include "FP.h"
+#include "MQTTSNPacket.h"
+#include "stdio.h"
+
+
+#define INFO_TRACE(_class, _string, ...) printf( "%8s: " _string, _class, ##__VA_ARGS__ )
+//#define TRACE(_string, ...) INFO_TRACE( "MQTT-SN", _string, ##__VA_ARGS__)
+#define TRACE(_string, ...)
+
+// Data limits
+#if !defined(MAX_REGISTRATIONS)
+ #define MAX_REGISTRATIONS 5
+#endif
+#if !defined(MAX_REGISTRATION_TOPIC_NAME_LENGTH)
+ #define MAX_REGISTRATION_TOPIC_NAME_LENGTH 20
+#endif
+#if !defined(MAX_INCOMING_QOS2_MESSAGES)
+ #define MAX_INCOMING_QOS2_MESSAGES 10
+#endif
+
+#if !defined(MQTTSNCLIENT_QOS1)
+ #define MQTTSNCLIENT_QOS1 1
+#endif
+#if !defined(MQTTSNCLIENT_QOS2)
+ #define MQTTSNCLIENT_QOS2 0
+#endif
+
+namespace MQTTSN
+{
+
+
+enum QoS { QOS0, QOS1, QOS2 };
+
+// all failure return codes must be negative
+enum returnCode { MAX_SUBSCRIPTIONS_EXCEEDED = -3, BUFFER_OVERFLOW = -2, FAILURE = -1, SUCCESS = 0 };
+
+
+struct Message
+{
+ enum QoS qos;
+ bool retained;
+ bool dup;
+ unsigned short id;
+ void *payload;
+ size_t payloadlen;
+};
+
+
+struct MessageData
+{
+ MessageData(MQTTSN_topicid &aTopic, struct Message &aMessage) : message(aMessage), topic(aTopic)
+ { }
+
+ struct Message &message;
+ MQTTSN_topicid &topic;
+};
+
+
+class PacketId
+{
+public:
+ PacketId()
+ {
+ next = 0;
+ }
+
+ int getNext()
+ {
+ if(next == MAX_PACKET_ID)
+ {
+ next = 1;
+ }
+ else
+ {
+ next++;
+ }
+ return next;
+ }
+
+private:
+ static const int MAX_PACKET_ID = 65535;
+ int next;
+};
+
+
+/**
+ * @class MQTTSNClient
+ * @brief blocking, non-threaded MQTTSN client API
+ *
+ * This version of the API blocks on all method calls, until they are complete. This means that only one
+ * MQTT request can be in process at any one time.
+ * @param Network a network class which supports send, receive
+ * @param Timer a timer class with the methods:
+ */
+template<class Network, class Timer, int MAX_PACKET_SIZE = 100, int MAX_MESSAGE_HANDLERS = 5>
+class Client
+{
+
+public:
+
+ typedef void (*messageHandler)(MessageData&);
+
+ /** Construct the client
+ * @param network - pointer to an instance of the Network class - must be connected to the endpoint
+ * before calling MQTT connect
+ * @param limits an instance of the Limit class - to alter limits as required
+ */
+ Client(Network& network, unsigned int command_timeout_ms = 30000);
+
+ /** Set the default message handling callback - used for any message which does not match a subscription message handler
+ * @param mh - pointer to the callback function
+ */
+ void setDefaultMessageHandler(messageHandler mh)
+ {
+ defaultMessageHandler.attach(mh);
+ }
+
+ /** MQTT Connect - send an MQTT connect packet down the network and wait for a Connack
+ * The nework object must be connected to the network endpoint before calling this
+ * Default connect options are used
+ * @return success code -
+ */
+ int connect();
+
+ /** MQTT Connect - send an MQTT connect packet down the network and wait for a Connack
+ * The nework object must be connected to the network endpoint before calling this
+ * @param options - connect options
+ * @return success code -
+ */
+ int connect(MQTTSNPacket_connectData& options);
+
+ /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
+ * @param topic - the topic to publish to
+ * @param message - the message to send
+ * @return success code -
+ */
+ int publish(MQTTSN_topicid& topic, Message& message);
+
+ /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
+ * @param topic - the topic to publish to
+ * @param payload - the data to send
+ * @param payloadlen - the length of the data
+ * @param qos - the QoS to send the publish at
+ * @param retained - whether the message should be retained
+ * @return success code -
+ */
+ int publish(MQTTSN_topicid &topic, void* payload, size_t payloadlen, enum QoS qos = QOS0, bool retained = false);
+
+ /** MQTT Publish - send an MQTT publish packet and wait for all acks to complete for all QoSs
+ * @param topic - the topic to publish to
+ * @param payload - the data to send
+ * @param payloadlen - the length of the data
+ * @param id - the packet id used - returned
+ * @param qos - the QoS to send the publish at
+ * @param retained - whether the message should be retained
+ * @return success code -
+ */
+ int publish(MQTTSN_topicid& topic, void* payload, size_t payloadlen, unsigned short& id, enum QoS qos = QOS1, bool retained = false);
+
+ /** MQTT Subscribe - send an MQTT subscribe packet and wait for the suback
+ * @param topicFilter - a topic pattern which can include wildcards
+ * @param qos - the MQTT QoS to subscribe at
+ * @param mh - the callback function to be invoked when a message is received for this subscription
+ * @return success code -
+ */
+ int subscribe(MQTTSN_topicid& topicFilter, enum QoS qos, enum QoS &grantedQoS, messageHandler mh);
+
+ /** MQTT Unsubscribe - send an MQTT unsubscribe packet and wait for the unsuback
+ * @param topicFilter - a topic pattern which can include wildcards
+ * @return success code -
+ */
+ int unsubscribe(MQTTSN_topicid& topicFilter);
+
+ /** MQTT Disconnect - send an MQTT disconnect packet, and clean up any state
+ * @param duration - used for sleeping clients, 0 means no duration
+ * @return success code -
+ */
+ int disconnect(unsigned short duration = 0);
+
+ /** A call to this API must be made within the keepAlive interval to keep the MQTT connection alive
+ * yield can be called if no other MQTT operation is needed. This will also allow messages to be
+ * received.
+ * @param timeout_ms the time to wait, in milliseconds
+ * @return success code - on failure, this means the client has disconnected
+ */
+ int yield(unsigned long timeout_ms = 1000L);
+
+ /** Is the client connected?
+ * @return flag - is the client connected or not?
+ */
+ bool isConnected()
+ {
+ return isconnected;
+ }
+
+protected:
+
+ int cycle(Timer& timer);
+ int waitfor(int packet_type, Timer& timer);
+
+private:
+
+ int keepalive();
+ int publish(int len, Timer& timer, enum QoS qos);
+
+ int readPacket(Timer& timer);
+ int sendPacket(int length, Timer& timer);
+ int deliverMessage(MQTTSN_topicid& topic, Message& message);
+ bool isTopicMatched(char* topicFilter, MQTTSNString& topicName);
+
+ Network& ipstack;
+ unsigned long command_timeout_ms;
+
+ unsigned char sendbuf[MAX_PACKET_SIZE];
+ unsigned char readbuf[MAX_PACKET_SIZE];
+
+ Timer last_sent, last_received;
+ unsigned short duration;
+ bool ping_outstanding;
+ bool cleansession;
+
+ PacketId packetid;
+
+ struct MessageHandlers
+ {
+ MQTTSN_topicid* topicFilter;
+ FP<void, MessageData&> fp;
+ } messageHandlers[MAX_MESSAGE_HANDLERS]; // Message handlers are indexed by subscription topic
+
+ FP<void, MessageData&> defaultMessageHandler;
+
+ bool isconnected;
+
+ struct Registrations
+ {
+ unsigned short id;
+ char name[MAX_REGISTRATION_TOPIC_NAME_LENGTH];
+ } registrations[MAX_REGISTRATIONS];
+
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ unsigned char pubbuf[MAX_PACKET_SIZE]; // store the last publish for sending on reconnect
+ int inflightLen;
+ unsigned short inflightMsgid;
+ enum QoS inflightQoS;
+#endif
+
+#if MQTTSNCLIENT_QOS2
+ bool pubrel;
+ unsigned short incomingQoS2messages[MAX_INCOMING_QOS2_MESSAGES];
+ bool isQoS2msgidFree(unsigned short id);
+ bool useQoS2msgid(unsigned short id);
+#endif
+
+};
+
+}
+
+
+template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
+MQTTSN::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::Client(Network& network, unsigned int command_timeout_ms) : ipstack(network), packetid()
+{
+ inflightLen = 0;
+ duration = 0;
+ cleansession = 0;
+ last_sent = Timer();
+ last_received = Timer();
+ ping_outstanding = false;
+ for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+ messageHandlers[i].topicFilter = 0;
+ this->command_timeout_ms = command_timeout_ms;
+ isconnected = false;
+
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ inflightMsgid = 0;
+ inflightQoS = QOS0;
+#endif
+
+
+#if MQTTSNCLIENT_QOS2
+ pubrel = false;
+ for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
+ incomingQoS2messages[i] = 0;
+#endif
+}
+
+#if MQTTSNCLIENT_QOS2
+template<class Network, class Timer, int a, int b>
+bool MQTTSN::Client<Network, Timer, a, b>::isQoS2msgidFree(unsigned short id)
+{
+ for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
+ {
+ if (incomingQoS2messages[i] == id)
+ return false;
+ }
+ return true;
+}
+
+
+template<class Network, class Timer, int a, int b>
+bool MQTTSN::Client<Network, Timer, a, b>::useQoS2msgid(unsigned short id)
+{
+ for (int i = 0; i < MAX_INCOMING_QOS2_MESSAGES; ++i)
+ {
+ if (incomingQoS2messages[i] == 0)
+ {
+ incomingQoS2messages[i] = id;
+ return true;
+ }
+ }
+ return false;
+}
+#endif
+
+
+template<class Network, class Timer, int a, int b>
+int MQTTSN::Client<Network, Timer, a, b>::sendPacket(int length, Timer& timer)
+{
+ int rc = FAILURE,
+ sent = 0;
+
+ do
+ {
+ sent = ipstack.write(sendbuf, length, timer.left_ms());
+ TRACE("sendPacket, rc %d from write of %d bytes\n", sent, length);
+ if (sent < 0) // there was an error writing the data
+ break;
+ }
+ while (sent != length && !timer.expired());
+
+ if (sent == length)
+ {
+ if (this->duration > 0)
+ last_sent.countdown(this->duration); // record the fact that we have successfully sent the packet
+ rc = SUCCESS;
+ }
+ else
+ rc = FAILURE;
+
+#if defined(MQTT_DEBUG)
+ char printbuf[50];
+ DEBUG("Rc %d from sending packet %s\n", rc, MQTTPacket_toString(printbuf, sizeof(printbuf), sendbuf, length));
+#endif
+ return rc;
+}
+
+
+/**
+ * If any read fails in this method, then we should disconnect from the network, as on reconnect
+ * the packets can be retried.
+ * @param timeout the max time to wait for the packet read to complete, in milliseconds
+ * @return the MQTT packet type, or -1 if none
+ */
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::readPacket(Timer& timer)
+{
+ int rc = FAILURE;
+ int len = 0; // the length of the whole packet including length field
+ int lenlen = 0;
+ int datalen = 0;
+
+ #define MQTTSN_MIN_PACKET_LENGTH 3
+ // 1. read the packet, datagram style
+ if ((len = ipstack.read(readbuf, MAX_PACKET_SIZE, timer.left_ms())) < MQTTSN_MIN_PACKET_LENGTH)
+ goto exit;
+
+ // 2. read the length. This is variable in itself
+ lenlen = MQTTSNPacket_decode(readbuf, len, &datalen);
+ if (datalen != len)
+ goto exit; // there was an error
+
+ rc = readbuf[lenlen];
+ if (this->duration > 0)
+ last_received.countdown(this->duration); // record the fact that we have successfully received a packet
+exit:
+
+#if defined(MQTT_DEBUG)
+ char printbuf[50];
+ DEBUG("Rc %d from receiving packet %s\n", rc, MQTTPacket_toString(printbuf, sizeof(printbuf), readbuf, len));
+#endif
+ return rc;
+}
+
+
+// assume topic filter and name is in correct format
+// # can only be at end
+// + and # can only be next to separator
+template<class Network, class Timer, int a, int b>
+bool MQTTSN::Client<Network, Timer, a, b>::isTopicMatched(char* topicFilter, MQTTSNString& topicName)
+{
+ char* curf = topicFilter;
+ char* curn = topicName.lenstring.data;
+ char* curn_end = curn + topicName.lenstring.len;
+
+ 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');
+}
+
+
+
+template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
+int MQTTSN::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::deliverMessage(MQTTSN_topicid& topic, Message& message)
+{
+ int rc = FAILURE;
+ TRACE("deliverMessage topic id is %d\n", topic.data.id);
+
+ // we have to find the right message handler - indexed by topic
+ for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+ {
+ if (messageHandlers[i].topicFilter != 0)
+ {
+ TRACE("messageHandler %d topic id is %d\n", i, messageHandlers[i].topicFilter->data.id);
+ }
+ if (messageHandlers[i].topicFilter != 0 && (topic.data.id == messageHandlers[i].topicFilter->data.id))
+ //MQTTSNtopic_equals(&topic, messageHandlers[i].topicFilter) ||
+ // isTopicMatched(messageHandlers[i].topicFilter, topic)))
+ {
+ if (messageHandlers[i].fp.attached())
+ {
+ MessageData md(topic, message);
+ messageHandlers[i].fp(md);
+ rc = SUCCESS;
+ }
+ }
+ }
+
+ if (rc == FAILURE && defaultMessageHandler.attached())
+ {
+ MessageData md(topic, message);
+ defaultMessageHandler(md);
+ rc = SUCCESS;
+ }
+
+ return rc;
+}
+
+
+
+template<class Network, class Timer, int a, int b>
+int MQTTSN::Client<Network, Timer, a, b>::yield(unsigned long timeout_ms)
+{
+ int rc = SUCCESS;
+ Timer timer = Timer();
+
+ timer.countdown_ms(timeout_ms);
+ while (!timer.expired())
+ {
+ if (cycle(timer) == FAILURE)
+ {
+ rc = FAILURE;
+ break;
+ }
+ }
+
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::cycle(Timer& timer)
+{
+ /* get one piece of work off the wire and one pass through */
+
+ // read the socket, see what work is due
+ unsigned short packet_type = readPacket(timer);
+
+ int len = 0;
+ int rc = SUCCESS;
+
+ switch (packet_type)
+ {
+ case MQTTSN_CONNACK:
+ case MQTTSN_PUBACK:
+ case MQTTSN_SUBACK:
+ case MQTTSN_REGACK:
+ break;
+ case MQTTSN_REGISTER:
+ {
+ unsigned short topicid, packetid;
+ MQTTSNString topicName;
+ unsigned char reg_rc = MQTTSN_RC_ACCEPTED;
+ if (MQTTSNDeserialize_register(&topicid, &packetid, &topicName, readbuf, MAX_PACKET_SIZE) != 1)
+ goto exit;
+ len = MQTTSNSerialize_regack(sendbuf, MAX_PACKET_SIZE, topicid, packetid, reg_rc);
+ if (len <= 0)
+ rc = FAILURE;
+ else
+ rc = sendPacket(len, timer);
+ break;
+ }
+ case MQTTSN_PUBLISH:
+ MQTTSN_topicid topicid;
+ Message msg;
+ if (MQTTSNDeserialize_publish((unsigned char*)&msg.dup, (int*)&msg.qos, (unsigned char*)&msg.retained, &msg.id, &topicid,
+ (unsigned char**)&msg.payload, (int*)&msg.payloadlen, readbuf, MAX_PACKET_SIZE) != 1)
+ goto exit;
+#if MQTTSNCLIENT_QOS2
+ if (msg.qos != QOS2)
+#endif
+ deliverMessage(topicid, msg);
+#if MQTTSNCLIENT_QOS2
+ else if (isQoS2msgidFree(msg.id))
+ {
+ if (useQoS2msgid(msg.id))
+ deliverMessage(topicid, msg);
+ else
+ WARN("Maximum number of incoming QoS2 messages exceeded");
+ }
+#endif
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ if (msg.qos != QOS0)
+ {
+ if (msg.qos == QOS1)
+ len = MQTTSNSerialize_puback(sendbuf, MAX_PACKET_SIZE, topicid.data.id, msg.id, 0);
+ else if (msg.qos == QOS2)
+ len = MQTTSNSerialize_pubrec(sendbuf, MAX_PACKET_SIZE, msg.id);
+ if (len <= 0)
+ rc = FAILURE;
+ else
+ {
+ TRACE("sending puback len %d\n", len);
+ rc = sendPacket(len, timer);
+ TRACE("rc %d from sending puback\n", rc);
+ }
+ if (rc == FAILURE)
+ goto exit; // there was a problem
+ }
+ break;
+#endif
+#if MQTTSNCLIENT_QOS2
+ case MQTTSN_PUBREC:
+ unsigned short mypacketid;
+ unsigned char type;
+ if (MQTTSNDeserialize_ack(&type, &mypacketid, readbuf, MAX_PACKET_SIZE) != 1)
+ rc = FAILURE;
+ else if ((len = MQTTSNSerialize_pubrel(sendbuf, MAX_PACKET_SIZE, mypacketid)) <= 0)
+ rc = FAILURE;
+ else if ((rc = sendPacket(len, timer)) != SUCCESS) // send the PUBREL packet
+ rc = FAILURE; // there was a problem
+ if (rc == FAILURE)
+ goto exit; // there was a problem
+ break;
+ case MQTTSN_PUBCOMP:
+ break;
+#endif
+ case MQTTSN_PINGRESP:
+ ping_outstanding = false;
+ break;
+ }
+ keepalive();
+exit:
+ if (rc == SUCCESS)
+ rc = packet_type;
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::keepalive()
+{
+ int rc = FAILURE;
+
+ if (duration == 0)
+ {
+ rc = SUCCESS;
+ goto exit;
+ }
+
+ if (last_sent.expired() || last_received.expired())
+ {
+ if (!ping_outstanding)
+ {
+ MQTTSNString clientid = MQTTSNString_initializer;
+ Timer timer = Timer(1000);
+ int len = MQTTSNSerialize_pingreq(sendbuf, MAX_PACKET_SIZE, clientid);
+ if (len > 0 && (rc = sendPacket(len, timer)) == SUCCESS) // send the ping packet
+ ping_outstanding = true;
+ }
+ }
+
+exit:
+ return rc;
+}
+
+
+// only used in single-threaded mode where one command at a time is in process
+template<class Network, class Timer, int a, int b>
+int MQTTSN::Client<Network, Timer, a, b>::waitfor(int packet_type, Timer& timer)
+{
+ int rc = FAILURE;
+
+ do
+ {
+ if (timer.expired())
+ break; // we timed out
+ }
+ while ((rc = cycle(timer)) != packet_type);
+
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::connect(MQTTSNPacket_connectData& options)
+{
+ Timer connect_timer = Timer(command_timeout_ms);
+ int rc = FAILURE;
+ int len = 0;
+
+ if (isconnected) // don't send connect packet again if we are already connected
+ goto exit;
+
+ this->duration = options.duration;
+ this->cleansession = options.cleansession;
+ if ((len = MQTTSNSerialize_connect(sendbuf, MAX_PACKET_SIZE, &options)) <= 0)
+ goto exit;
+ if ((rc = sendPacket(len, connect_timer)) != SUCCESS) // send the connect packet
+ goto exit; // there was a problem
+
+ if (this->duration > 0)
+ last_received.countdown(this->duration);
+ // this will be a blocking call, wait for the connack
+ if (waitfor(MQTTSN_CONNACK, connect_timer) == MQTTSN_CONNACK)
+ {
+ //unsigned char connack_rc = 255;
+ int connack_rc = 255;
+ if (MQTTSNDeserialize_connack(&connack_rc, readbuf, MAX_PACKET_SIZE) == 1)
+ rc = connack_rc;
+ else
+ rc = FAILURE;
+ }
+ else
+ rc = FAILURE;
+
+#if MQTTSNCLIENT_QOS2
+ // resend an inflight publish
+ if (inflightMsgid >0 && inflightQoS == QOS2 && pubrel)
+ {
+ if ((len = MQTTSNSerialize_pubrel(sendbuf, MAX_PACKET_SIZE, inflightMsgid)) <= 0)
+ rc = FAILURE;
+ else
+ rc = publish(len, connect_timer, inflightQoS);
+ }
+ else
+#endif
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ if (inflightMsgid > 0)
+ {
+ memcpy(sendbuf, pubbuf, MAX_PACKET_SIZE);
+ rc = publish(inflightLen, connect_timer, inflightQoS);
+ }
+#endif
+
+exit:
+ if (rc == SUCCESS)
+ isconnected = true;
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::connect()
+{
+ MQTTSNPacket_connectData default_options = MQTTSNPacket_connectData_initializer;
+ return connect(default_options);
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::subscribe(MQTTSN_topicid& topicFilter, enum QoS qos, enum QoS &grantedQoS, messageHandler messageHandler)
+{
+ int rc = FAILURE;
+ Timer timer = Timer(command_timeout_ms);
+ int len = 0;
+ bool freeHandler = false;
+
+ if (!isconnected)
+ goto exit;
+
+ for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+ {
+ if (messageHandlers[i].topicFilter == 0)
+ {
+ freeHandler = true;
+ break;
+ }
+ }
+ if (!freeHandler)
+ { // No message handler free
+ rc = MAX_SUBSCRIPTIONS_EXCEEDED;
+ goto exit;
+ }
+
+ len = MQTTSNSerialize_subscribe(sendbuf, MAX_PACKET_SIZE, 0, qos, packetid.getNext(), &topicFilter);
+ if (len <= 0)
+ goto exit;
+ if ((rc = sendPacket(len, timer)) != SUCCESS) // send the subscribe packet
+ goto exit; // there was a problem
+
+ if (waitfor(MQTTSN_SUBACK, timer) == MQTTSN_SUBACK) // wait for suback
+ {
+ unsigned short mypacketid;
+ unsigned char suback_rc;
+ if (MQTTSNDeserialize_suback((int*)&grantedQoS, &topicFilter.data.id, &mypacketid, &suback_rc, readbuf, MAX_PACKET_SIZE) != 1)
+ rc = FAILURE;
+ else
+ rc = suback_rc;
+ if (suback_rc == MQTTSN_RC_ACCEPTED)
+ {
+ for (int i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
+ {
+ if (messageHandlers[i].topicFilter == 0)
+ {
+ messageHandlers[i].topicFilter = &topicFilter;
+ messageHandlers[i].fp.attach(messageHandler);
+ rc = 0;
+ break;
+ }
+ }
+ }
+ }
+ else
+ rc = FAILURE;
+
+exit:
+ if (rc != SUCCESS)
+ isconnected = false;
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int MAX_MESSAGE_HANDLERS>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, MAX_MESSAGE_HANDLERS>::unsubscribe(MQTTSN_topicid& topicFilter)
+{
+ int rc = FAILURE;
+ Timer timer = Timer(command_timeout_ms);
+ int len = 0;
+
+ if (!isconnected)
+ goto exit;
+
+ if ((len = MQTTSNSerialize_unsubscribe(sendbuf, MAX_PACKET_SIZE, packetid.getNext(), &topicFilter)) <= 0)
+ goto exit;
+ if ((rc = sendPacket(len, timer)) != SUCCESS) // send the unsubscribe packet
+ goto exit; // there was a problem
+
+ if (waitfor(MQTTSN_UNSUBACK, timer) == MQTTSN_UNSUBACK)
+ {
+ unsigned short mypacketid; // should be the same as the packetid above
+ if (MQTTSNDeserialize_unsuback(&mypacketid, readbuf, MAX_PACKET_SIZE) == 1)
+ rc = 0;
+ }
+ else
+ rc = FAILURE;
+
+exit:
+ if (rc != SUCCESS)
+ isconnected = false;
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::publish(int len, Timer& timer, enum QoS qos)
+{
+ int rc;
+
+ if ((rc = sendPacket(len, timer)) != SUCCESS) // send the publish packet
+ goto exit; // there was a problem
+
+#if MQTTSNCLIENT_QOS1
+ if (qos == QOS1)
+ {
+ if (waitfor(MQTTSN_PUBACK, timer) == MQTTSN_PUBACK)
+ {
+ unsigned short mypacketid;
+ unsigned char type;
+ if (MQTTSNDeserialize_ack(&type, &mypacketid, readbuf, MAX_PACKET_SIZE) != 1)
+ rc = FAILURE;
+ else if (inflightMsgid == mypacketid)
+ inflightMsgid = 0;
+ }
+ else
+ rc = FAILURE;
+ }
+#elif MQTTSNCLIENT_QOS2
+ else if (qos == QOS2)
+ {
+ if (waitfor(PUBCOMP, timer) == PUBCOMP)
+ {
+ unsigned short mypacketid;
+ unsigned char type;
+ if (MQTTDeserialize_ack(&type, &mypacketid, readbuf, MAX_PACKET_SIZE) != 1)
+ rc = FAILURE;
+ else if (inflightMsgid == mypacketid)
+ inflightMsgid = 0;
+ }
+ else
+ rc = FAILURE;
+ }
+#endif
+
+exit:
+ if (rc != SUCCESS)
+ isconnected = false;
+ return rc;
+}
+
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::publish(MQTTSN_topicid& topic, void* payload, size_t payloadlen, unsigned short& id, enum QoS qos, bool retained)
+{
+ int rc = FAILURE;
+ Timer timer = Timer(command_timeout_ms);
+ int len = 0;
+
+ if (!isconnected)
+ goto exit;
+
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ if (qos == QOS1 || qos == QOS2)
+ id = packetid.getNext();
+#endif
+
+ len = MQTTSNSerialize_publish(sendbuf, MAX_PACKET_SIZE, 0, qos, retained, id,
+ topic, (unsigned char*)payload, payloadlen);
+ if (len <= 0)
+ goto exit;
+
+#if MQTTSNCLIENT_QOS1 || MQTTSNCLIENT_QOS2
+ if (!cleansession)
+ {
+ memcpy(pubbuf, sendbuf, len);
+ inflightMsgid = id;
+ inflightLen = len;
+ inflightQoS = qos;
+#if MQTTSNCLIENT_QOS2
+ pubrel = false;
+#endif
+ }
+#endif
+
+ rc = publish(len, timer, qos);
+exit:
+ return rc;
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::publish(MQTTSN_topicid& topicName, void* payload, size_t payloadlen, enum QoS qos, bool retained)
+{
+ unsigned short id = 0; // dummy - not used for anything
+ return publish(topicName, payload, payloadlen, id, qos, retained);
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::publish(MQTTSN_topicid& topicName, Message& message)
+{
+ return publish(topicName, message.payload, message.payloadlen, message.qos, message.retained);
+}
+
+
+template<class Network, class Timer, int MAX_PACKET_SIZE, int b>
+int MQTTSN::Client<Network, Timer, MAX_PACKET_SIZE, b>::disconnect(unsigned short duration)
+{
+ int rc = FAILURE;
+ Timer timer = Timer(command_timeout_ms); // we might wait for incomplete incoming publishes to complete
+ int int_duration = (duration == 0) ? -1 : (int)duration;
+ int len = MQTTSNSerialize_disconnect(sendbuf, MAX_PACKET_SIZE, int_duration);
+ if (len > 0)
+ rc = sendPacket(len, timer); // send the disconnect packet
+
+ isconnected = false;
+ return rc;
+}
+
+
+#endif